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  • IPEN-DOC 29685

    GALLO, JULIANA M.A.S.; SANTOS, ELAINE M.; GONCALVES, MARCELA L.L.; SOBRAL, ANA P.T.; RAIMUNDO, DANIELE; NASCIMENTO, ALANA R.; BUSSADORI, SANDRA K.; AZEVEDO, MILTON R.; SABATO, SUSY F. . Avaliação sensorial e pH de molhos para saladas tratados por radiação gama / Sensory evaluation and pH of salad dressings treated by gamma radiation. Research, Society and Development, v. 12, n. 2, p. 1-8, 2023. DOI: 10.33448/rsd-v12i2.39157

    Abstract: Avaliou-se as medida de pH de molhos para salada pronto para consumo com o objetivo de verificar sua estabilidade diante dos diferentes tratamentos com doses de radiação gama. Análises sensoriais, de dois dos molhos estudados foram conduzidas com o objetivo de avaliar a aceitação por consumidores diante da irradiação. de molhos comerciais para salada, tratados pelo processo de irradiação por raios gama, nas doses: 3 kGy e 5 kGy. Realizou-se o protocolo de estudo em duas fases. Na fase 1, as análises foram conduzidas logo após as amostras terem sido irradiadas, as quais se encontravam próximas a suas datas de fabricação. Na fase 2 as amostras foram reavaliadas após um período de armazenamento, próximo a data de expiração de suas validades. A irradiação, nas doses absorvidas estudadas, não influenciou o pH e os resultados da análise sensorial indicaram boa aceitação dos molhos irradiados pelos provadores.

    Palavras-Chave: food processing; irradiation; food; organic wastes; gamma radiation; taste buds

  • IPEN-DOC 29684

    SCURO, N.L. ; ANGELO, G.; ANGELO, E.; PIRO, M.H.A.; UMBEHAUN, P.E. ; TORRES, W.M. ; ANDRADE, D.A. . Computational fluid dynamics analysis of an open-pool nuclear research reactor core for fluid flow optimization using a channel box. Nuclear Science and Engineering, v. 197, n. 6, p. 1100-1116, 2023. DOI: 10.1080/00295639.2022.2142437

    Abstract: A channel box installation in the IEA-R1 research reactor core was numerically investigated to increase fluid flow in fuel assemblies (FAs) and side water channels (SWCs) between FAs by minimizing bypasses in specific regions of the reactor core, which is expected to reduce temperatures and oxidation effects in lateral fuel plates (LFPs). To achieve this objective, an isothermal three-dimensional computational fluid dynamics model was created using Ansys CFX to analyze fluid flow distribution in the Brazilian IEA-R1 research reactor core. All regions of the core and realistic boundary conditions were considered, and a detailed mesh convergence study is presented. Results comparing both scenarios are presented in the percentage of use of the primary circuit pump. It is indicated that 21.4% of fluid bypass to unnecessary regions can be avoided with the channel box installation, which leads to the total mass flow from the primary circuit for all FAs increasing from 68.9% (without a channel box) to 77.6% (with a channel box). For the SWCs, responsible for cooling LFPs, an increment from 9.7% to 22.4%, avoiding all nondesired cross three-dimensional effects, was observed, resulting in a more homogeneous fluid flow and vertical velocities. It was concluded that the installation of a channel box numerically indicates an expressive mass flow increase and homogeneous fluid flow distribution for flow dynamics in relevant regions. This gives greater confidence to believe that lower temperatures, and consequently oxidation effects in LFPs, can be expected with a channel box installation.

    Palavras-Chave: computer codes; fluid mechanics; reactor cores; distribution; fluid flow

  • IPEN-DOC 29683

    ESQUIVEL-HERNANDEZ, GERMAIN; MATIATOS, IOANNIS; SANCHEZ-MURILLO, RICARDO; VYSTAVNA, YULIYA; BALESTRINI, RAFFAELLA; WELLS, NAOMI S.; MONTEIRO, LUCILENA R. ; CHANTARA, SOMPORN; WALTERS, WENDELL; WASSENAAR, LEONARD I.. Nitrate isotopes (δ15N, δ18O) in precipitation: best practices from an international coordinated research project. Isotopes in Environmental and Health Studies, v. 59, n. 2, p. 127-141, 2023. DOI: 10.1080/10256016.2023.2177649

    Abstract: Stable isotope ratios of nitrogen and oxygen (15N/14N and 18O/16O) of nitrate (NO3–) are excellent tracers for developing systematic understanding of sources, conversions, and deposition of reactive atmospheric nitrogen (Nr) in the environment. Despite recent analytical advances, standardized sampling of NO3–) isotopes in precipitation is still lacking. To advance atmospheric studies on Nr species, we propose best-practice guidelines for accurate and precise sampling and analysis of NO3– isotopes in precipitation based on the experience obtained from an international research project coordinated by the International Atomic Energy Agency (IAEA). The precipitation sampling and preservation strategies yielded a good agreement between the NO3– concentrations measured at the laboratories of 16 countries and at the IAEA. Compared to conventional methods (e.g., bacterial denitrification), we confirmed the accurate performance of the lower cost Ti(III) reduction method for isotope analyses (15N and 18O) of NO3– in precipitation samples. These isotopic data depict different origins and oxidation pathways of inorganic nitrogen. This work emphasized the capability of NO3– isotopes to assess the origin and atmospheric oxidation of Nr and outlined a pathway to improve laboratory capability and expertise at a global scale. The incorporation of other isotopes like 17O in Nr is recommended in future studies.

    Palavras-Chave: nitrates; isotopes; nitrogen 15; geochemistry; oxygen 18; precipitation; inorganic compounds; regulatory guides; calibration standards

  • IPEN-DOC 29682

    SILVA, REJANE M.P. da ; MILAGRE, MARIANA X. ; ARAUJO, JOAO V. de S. ; RAMIREZ, OSCAR M.P.; MACHADO, CARULINE de S.C. ; ANTUNES, RENATO A.; COSTA, ISOLDA . Investigação da atividade eletroquímica de liga Al-Cu-Li após processo de soldagem por fricção e mistura / Investigation of the electrochemical activity of an Al-Cu-Li alloy after friction stir welding process. Quimica Nova, v. 46, n. 4, p. 307-318, 2023. DOI: 10.21577/0100-4042.20230014

    Abstract: In this work, the local electrochemical activity of the zones coupled by Friction Stir Welding (FSW) of an Al-Cu-Li alloy was studied and the results were correlated to the microstructural characteristics of each zone. Electrochemical studies were carried out in the zones affected by welding using cyclic voltammetry (CV) and scanning electrochemical techniques (namely, SECM - Scanning Electrochemical Microscopy and LEIS – Local electrochemical impedance spectroscopy). The results showed that the welding joint (WJ) is predominantly cathodic relatively to the heat affected zones (HAZ). The HAZ was always anodic and showed the highest electrochemical activities among the tested ones. The high electrochemical activity of the HAZ was associated with the effect of galvanic coupling between the cathodic region (WJ) and the anodic region (HAZ). In addition, the advancing side (AS) presented increased electrochemical activity compared to the retreating one (RS).

    Palavras-Chave: friction welding; aluminium alloys; copper alloys; lithium alloys; electrochemistry

  • IPEN-DOC 29681

    PRADO, E.S.P.; MIRANDA, F.S.; ARAUJO, L.G. de ; FERNANDES, G.L.; PEREIRA, A.L.J.; GOMES, M.C.; SILVA SOBRINHO, A.S. da; BALDAN, M.R.; PETRACONI, G.. Physicochemical modifications and decolorization of textile wastewater by ozonation: performance evaluation of a batch system. Ozone: Science and Engineering, v. 45, n. 3, p. 276-290, 2023. DOI: 10.1080/01919512.2022.2088470

    Abstract: This is an experimental study on the decolorization efficiency and the degradation of organic compounds from textile wastewater by the ozonation process in a batch system. The effects of different sample volumes of textile wastewater over time were investigated. The experiments were performed in a 1 L glass reactor with a magnetic stirrer and a bubble diffuser at the bottom to feed the ozone. The applied cumulative ozone dosage varied at 120 gO3 L−1, 60 gO3 L−1, and 30 gO3 L−1, and the total interaction time for each test was 1 h. To investigate the physicochemical properties of the textile wastewater (solid and liquid phases) before and after the treatment, multiple analytical characterization methods were used: Thermal Gravimetric Analysis, Scanning Electron Microscopy coupled with Energy-Dispersive X-ray Spectroscopy, X-ray diffraction, Fourier Transform Infrared spectroscopy, and Spectrophotometer. The most perceptive change was observed in the color of the liquid medium, which turned from black to transparent, and a visual color number indicator known as DurchsichtFarbZahl (DFZ) was used for the evaluation of this process. Absorbance values decreased about 3.5 times after 5 min of treatment with a 0.15 L sample volume, and these values differed for tests with larger sample volumes. FTIR spectroscopy demonstrated that the bands’ intensities associated with the C − H, C − N, and C − O decrease during treatment. On the other hand, it was possible to conclude that combining treatment methods to improve the degradation of persistent compounds after the ozonation process is necessary. Finally, the ozonation of the textile wastewater proved to be effective at removing color due to its high reaction capacity.

    Palavras-Chave: textile industry; waste water; ozonization; dyes; removal

  • IPEN-DOC 29680

    SILVA, ARACELI J. ; ZAMBIAZI, PRISCILLA J. ; GOMES, PAULO V.R. ; NANDENHA, JULIO ; GODOI, CAMILA M. ; SOUZA, RODRIGO F.B. de ; NETO, ALMIR O. ; AZEREDO, NATHALIA F.B. . Conversão de metano em metanol com co-geração de energia elétrica a partir de catalisadores de paládio suportados em carbono / Conversion of methane to methanol with co-generation of electricity from palladium catalysts supported in carbon. Revista Virtual de Química, v. 15, n. 2, p. 221-226, 2023. DOI: 10.21577/1984-6835.20220101

    Abstract: The application of solid electrolyte reactors for methane oxidation and energy co-generation is attractive, especially with the use of catalysts synthesized from noble metals such as palladium. In this work, we prepared three different compositions of palladium on carbon support to evaluate the composition that had the greatest potential for energy generation. Catalysts in the proportions of 5, 10 and 20% of Pd/C were tested for the conversion of greenhouse gases into organic molecules of higher added value using electrochemical fuel cell solid electrolyte reactors. The focus of this work was the conversion of methane into methanol, using the fuel cell as a reactor and the commercial Pd/C as electrocatalyst. The electrocatalysts were tested at the anode, analyzed by infrared (IR) spectroscopy and their activities verified by experiments with rotating ring disk electrode (RRDE). Higher levels of palladium (Pd/C 20%) favored obtaining electrical power, and the intermediate composition (Pd/C 10%) showed a greater production of less oxidized compounds, such as methanol, in addition to generating electricity.

    Palavras-Chave: methane; oxidation; palladium; catalysts; fuel cells

  • IPEN-DOC 29679

    VILLARDI, BRUNO D.Q. ; FILHO, NIVALDO G.P. ; GOMES, PAULO V.R. ; NANDENHA, JULIO ; GODOI, CAMILA M. ; TAGOMORI, THAIS L. ; AZEREDO, NATHALIA ; SOUZA, RODRIGO F.B. de ; NETO, ALMIR O. ; ZAMBIAZI, PRISCILLA J. . Desempenho eletrocatalítico de Pd/C e Pt/C para geração de energia a partir do extrato de cana-de-açúcar em célula a combustível de líquido direto / Electrocatalytic performance of Pd/C and Pt/C for power generation from sugarcane extract in direct liquid fuel cell. Revista Virtual de Química, v. 15, n. 2, p. 241-247, 2023. DOI: 10.21577/1984-6835.20220140

    Abstract: The processing of biomass to obtain fuels such as ethanol results in generating waste and polluting the environment. However, to meet energy demand and simultaneously reduce environmental pollution, fuel cells are promising devices for converting chemical compounds into electricity. Fuel cells can be powered by various types of liquids, including the sugars available in sugarcane extract, with high energy potential. Fuel cells employ the use of noble metals as electrocatalysts, such as Pt or Pd, to carry out the oxidation of these fuels. In this sense, this work reports the study of the oxidation of sugarcane extract in these different noble metals. The platinum catalyst was shown to be more active for the oxidation of sugars, resulting in a power density 10 times greater than Pd/C using a 50% diluted sugarcane extract solution, resulting in promising fuel cell systems. To produce ecologically correct electrical energy for the industry in general.

    Palavras-Chave: biomass; sugar cane; renewable energy sources; electrocatalysts; fuel cells

  • IPEN-DOC 29678

    GROSSI, DANIELLE; LAZAR, DOLORES R.R. ; DEL LAMA, ELIANE A.; USSUI, VALTER . Titania-silica composite with photocatalytic properties and its application on Brazilian granite and sandstone. International Journal of Architectural Heritage, v. 17, n. 5, p. 770-787, 2023. DOI: 10.1080/15583058.2021.1969483

    Abstract: The aim of the study described in this article was to evaluate a product containing titania (titanium dioxide, TiO2) applied on stones — particularly two types used at Brazilian stone-built heritage sites — that have been exposed to weathering and anthropogenic activities. This product was prepared by producing a suspension of TiO2 at two concentrations (1% and 4% w/v) with tetraethyl orthosilicate (TEOS) in the presence of n-octylamine as surfactant. The characteristics of the TiO2 were then observed by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface-area measurements, particle-size distribution analysis (CILAS) and X-ray diffraction. After applying the TiO2-TEOS composite, the stones were examined for contact angle, spectrophotometry, sorptivity, thermal shock resistance, and UV-radiation resistance. The product proved ineffective on Itararé sandstone, mainly due to its mineralogical components, as the product does not adhere to quartz. When applied on Itaquera granite, the 1% TiO2 (w/v) concentration proved to be an appropriate treatment, as it demonstrated better thermal shock resistance, photocatalytic activity, porosity maintenance, and global colour when compared to the 4% concentration.

    Palavras-Chave: architecture; cultural resources; photocatalysis; sandstones; composite materials; titanium oxides

  • IPEN-DOC 29654

    COURROL, LILIA C.; KASSAB, LUCIANA R.P.; FUKUMOTO, MARCOS E.; GOMES, LAERCIO ; WETTER, NIKLAUS U. ; VIEIRA JUNIOR, NILSON D. ; CASSANJES, FABIA C.; MESSADDEQ, YOUNES; RIBEIRO, SIDNEY J.L.. Evaluation of the most suitable new glass laser medium to incorporate Ytterbium: Alkali Niobium Tellurite, Lead Fluorborate or Heavy Metal Oxide. Boletim Técnico da Faculdade de Tecnologia de São Paulo, v. 12, 2002.

    Abstract: The most important advantage of Ytterbium compared to others dopants such as Neodymium is its broadband emission nature, which is very suitable for both tunable and ultrafast lasers. In this paper we present the study and characterization of three different glass families: Alkali Niobium Tellurite, Lead Fluoroborate and of Heavy Metal Oxides, all prepared containing Ytterbium. The Ytterbium (Yb) emission spectrum in Tellurite glass samples was obtained by excitation into the absorption peak at 975 nm. The Yb peak emission cross-section was calculated using the fluorescence lineshape, the radiative lifetime (0.59 ms) and the refractive index 2.09. With these values we found the emission cross-section of Yb in Tellurite glass doped. Lead Fluorborate glasses have high refractive index of 2.2, and an absorption band centered at 968nm. The spontaneous emission probability was calculated and we determined that it decreases with the increase of Yb concentration. The same applies for the fluorescence lifetime and to the emission cross-section. We measured the fluorescence lifetime of 0.81ms, and an emission band at 1022nm with an effective emission linewidth of 60nm. Heavy metal oxide glass also has high refractive index (2.5) and transmission cutoff of about 8mm. In this glass the fluorescence effective linewidth was 86nm and radiative lifetime 300 ms. Calculations of the minimum pump intensity are also presented. A comparison of laser properties of these three different glasses and their importance is shown and analyzed.

  • IPEN-DOC 29640

    SILVA, DANIEL J. da; DURAN, ADRIANA; CABRAL, ALINE D.; FONSECA, FERNANDO L.A.; WANG, SHU H.; PARRA, DUCLERC F. ; BUENO, RODRIGO F.; PEREYRA, INES; ROSA, DERVAL S.. Bioinspired antimicrobial PLA with nanocones on the surface for rapid deactivation of Omicron SARS-CoV‑2. ACS Biomaterials Science and Engineering, v. 9, n. 4, p. 1891-1899, 2023. DOI: 10.1021/acsbiomaterials.2c01529

    Abstract: Bioinspired bactericidal surfaces are artificial surfaces that mimic the nanotopography of insect wings and are capable of inhibiting microbial growth by a physicomechanical mechanism. The scientific community has considered them an alternative method to design polymers with surfaces that inhibit bacterial biofilm formation, suitable for self-disinfectant medical devices. In this contribution, poly(lactic acid) (PLA) with nanocone patterns was successfully produced by a novel two-step procedure involving copper plasma deposition followed by argon plasma etching. According to reverse transcription-quantitative polymerase chain reaction tests, the bioinspired PLA nanostructures display antiviral performance to inactivate infectious Omicron severe acute respiratory syndrome coronavirus 2 particles, reducing the amount of the viral genome to less than 4% in just 15 min due to a possible combined effect of mechanical and oxidative stress. The bioinspired antiviral PLA can be suitable for designing personal protection equipment to prevent the transmission of contagious viral diseases, such as Coronavirus Disease 2019.

    Palavras-Chave: coronaviruses; topography; surfaces; copper; lactic acid; polymers; antimicrobial agents

  • IPEN-DOC 29639

    SANTOS, SOFIA N. dos ; GUSHIKEN JUNIOR, DINO S. ; PEREIRA, JHONATAS P.M. ; IADOCICCO, NATALIA M. ; SILVA, ANDRE H. ; NASCIMENTO, TATIELLE do; DIAS, LUIS A.P. ; SILVA, FLAVIA R. de O. ; RICCI-JUNIOR, EDUARDO; SANTOS-OLIVEIRA, RALPH; BERNARDES, EMERSON S. . Development of glycan‑targeted nanoparticles as a novel therapeutic opportunity for gastric cancer treatment. Cancer Nanotechnology, v. 14, n. 1, p. 1-21, 2023. DOI: 10.1186/s12645-023-00161-2

    Abstract: Chemotherapy resistance remains a major cause of therapeutic failure in gastric cancer. The combination of genetic material such as interference RNAs (iRNAs) to silence cancer-associated genes with chemotherapeutics has become a novel approach for cancer treatment. However, finding the right target genes and developing non-toxic, highly selective nanocarrier systems remains a challenge. Here we developed a novel sialyl-Tn-targeted polylactic acid—didodecyldimethylammonium bromide nanoparticle (PLA-DDAB) nanoparticles (NPs) loaded with dsRNA targeting ST6GalNac-I and/or galectin-3 genes. Using single photon emission computed tomography (SPECT), we have demonstrated that 99mtechnetium radiolabeled sialyl-Tn-targeted nanoparticles can reach the tumor site and downregulate ST6GalNAc-I and galectin-3 RNA expression levels when injected intravenously. Furthermore, using an in vivo gastric tumor model, these nanoparticles increased the effectiveness of 5-FU in reducing tumor growth. Our findings indicate that cancer-associated glycan-targeted NPs loaded with dsRNA targeting ST6GalNAc-I and/or galectin-3 in combination with standard chemotherapy, have the potential to become a novel therapeutic tool for gastric cancer.

    Palavras-Chave: neoplasms; stomach; rna; antigens; chemotherapy

  • IPEN-DOC 29638

    MIRANDA, RANULFO B. de P.; USSUI, VALTER ; LAZAR, DOLORES R.R. ; LIMA, NELSON B. de ; MARCHI, JULIANA; CESAR, PAULO F.. Characterization of 3Y-TZP/TiO2 hybrid experimental dental ceramics. Ceramics International, v. 49, n. 10, p. 15734-15740, 2023. DOI: 10.1016/j.ceramint.2023.01.167

    Abstract: The addition of titania to zirconia dental implants has been considered a promising choice to improve its bioactivity. This study aimed to evaluate the effect of different sintering conditions on the microstructure, density, optical properties and flexural strength of a 3Y-TZP/TiO2 dental ceramic based on zirconia with two different titania contents (7.5 mol% and 12.5 mol%). 3Y-TZP/TiO2 ceramic powders were synthesized by coprecipitation, uniaxially pressed and sintered at six different sintering conditions. Microstructural analysis of the sintered samples was performed by scanning electron microscopy and X-ray diffraction. Optical properties were measured using a spectrophotometer. The density was determined by Archimedes principle. Flexural strength was estimated by the biaxial flexure device. The microstructure and flexural strength of the 3Y-TZP/TiO2 dental ceramic with 7.5% and 12.5 mol% were affected by the sintering conditions. Sintering the specimens at 1460 °C for 2 h increased the grain size and significantly decreased the flexural strength of 3Y-TZP/TiO2 dental ceramic. The interaction (titania content x sintering conditions) affected the relative density and optical properties. A relative density greater than 98% was achieved for the T7.5 groups (sintered at 1260 °C/1 h, 1300 °C/1 h and 1300 °C/2 h) and for the T12.5 groups (sintered at 1260 °C/1 h, 1260 °C/4 h, 1300 °C/1 h and 1300 °C/2 h). The highest values of L*, a* and b* were respectively 87.2 (T7.5 group sintered at 1460 °C/2hs), 4.3 (T12.5 group sintered at 1300 °C/2hs) and 15.8 (T12.5 group sintered at 1300 °C/1 h). The material developed with 12.5 mol% of titania and sintered at 1300 °C/2 h showed high densification, flexural strength of 670 MPa and has good potential to be used in dentistry.

    Palavras-Chave: yttrium oxides; zirconium oxides; titanium oxides; dentistry; ceramics; implants; optical properties; flexural strength; sintering

  • IPEN-DOC 29637

    YOSHIMURA, TANIA M. ; CABRAL, FERNANDA V. ; SELLERA, FABIO P.; POZZO, LORENA ; RIBEIRO, MARTHA S. . Could light-based technologies improve stem cell therapy for skin wounds?: A systematic review and meta-analysis of preclinical studies. Photochemistry and Photobiology, v. 99, n. 2, p. 519-528, 2023. DOI: 10.1111/php.13702

    Abstract: Several diseases or conditions cause dermatological disorders that hinder the process of skin repair. The search for novel technologies has inspired the combination of stem cell (SC) and light-based therapies to ameliorate skin wound repair. Herein, we systematically revised the impact of photobiomodulation therapy (PBM) combined with SCs in animal models of skin wounds and quantitatively evaluated this effect through a meta-analysis. For inclusion, SCs should be irradiated in vitro or in vivo, before or after being implanted in animals, respectively. The search resulted in nine eligible articles, which were assessed for risk of bias. For the meta-analysis, studies were included only when PBM was applied in vivo, five regarding wound closure, and three to wound strength. Overall, a positive influence of SC + PBM on wound closure (mean difference: 9.69; 95% CI: 5.78–13.61, P < 0.00001) and strength (standardized mean difference: 1.7, 95% CI: 0.68–2.72, P = 0.001) was detected, although studies have shown moderate to high heterogeneity and a lack of information regarding some bias domains. Altogether, PBM seems to be an enabling technology able to be applied postimplantation of SCs for cutaneous regeneration. Our findings may guide future laboratory and clinical studies in hopes of offering wound care patients a better quality of life.

    Palavras-Chave: skin diseases; therapy; stem cells; biological repair

  • IPEN-DOC 29636

    SABINO, CAETANO P.; RIBEIRO, MARTHA S. ; WAINWRIGHT, MARK; ANJOS, CAROLINA dos; SELLERA, FABIO P.; DROPA, MILENA; NUNES, NATHALIA B.; BRANCINI, GUILHERME T.P.; BRAGA, GILBERTO U.L.; ARANA-CHAVEZ, VICTOR E.; FREITAS, RAUL O.; LINCOPAN, NILTON; BAPTISTA, MAURICIO S.. The biochemical mechanisms of antimicrobial photodynamic therapy. Photochemistry and Photobiology, v. 99, n. 2, p. 742-750, 2023. DOI: 10.1111/php.13685

    Abstract: The unbridled dissemination of multidrug-resistant pathogens is a major threat to global health and urgently demands novel therapeutic alternatives. Antimicrobial photodynamic therapy (aPDT) has been developed as a promising approach to treat localized infections regardless of drug resistance profile or taxonomy. Even though this technique has been known for more than a century, discussions and speculations regarding the biochemical mechanisms of microbial inactivation have never reached a consensus on what is the primary cause of cell death. Since photochemically generated oxidants promote ubiquitous reactions with various biomolecules, researchers simply assumed that all cellular structures are equally damaged. In this study, biochemical, molecular, biological and advanced microscopy techniques were employed to investigate whether protein, membrane or DNA damage correlates better with dose-dependent microbial inactivation kinetics. We showed that although mild membrane permeabilization and late DNA damage occur, no correlation with inactivation kinetics was found. On the other hand, protein degradation was analyzed by three different methods and showed a dose-dependent trend that matches microbial inactivation kinetics. Our results provide a deeper mechanistic understanding of aPDT that can guide the scientific community toward the development of optimized photosensitizing drugs and also rationally propose synergistic combinations with antimicrobial chemotherapy.

    Palavras-Chave: antimicrobial agents; photodynamic therapy; biochemical reaction kinetics; microbial drug resistance

  • IPEN-DOC 29635

    TESSARO, ANA P.G. ; ARAUJO, LEANDRO G. de ; SILVA, THALITA T. ; COELHO, EDNEI; CORREA, BENEDITO; ROLINDO, NATALIE C. ; VICENTE, ROBERTO . Prospects for fungal bioremediation of unburied waste packages from the Goiânia radiological accident. Environmental Science and Pollution Research, v. 30, n. 14, p. 41045-41059, 2023. DOI: 10.1007/s11356-023-25247-7

    Abstract: Goiânia, the Goiás State capital, starred in 1987, where one of the largest radiological accidents in the world happened. A teletherapy machine was subtracted from a derelict radiotherapy clinic and disassembled by scavengers who distributed fragments of the 50 TBq 137CsCl source among relatives and acquaintances, enchanted by the blue shine of the substance. During the 15 days before the accident was acknowledged, contaminated recycling materials were delivered to recycling factories in four cities in the state of São Paulo, Brazil, in the form of recycling paper bales. The contaminated bales were spotted, collected, and stored in fifty 1.6 m3 steel boxes at the interim storage facility of the Nuclear and Energy Research Institute (IPEN). In 2017, a check of the content was performed in a few boxes and the presence of high moisture content was observed even though the bales were dry when conditioned and the packages were kept sealed since then. The main objective of this work was to report the fungi found in the radioactive waste after they evolved for 30 years in isolation inside the waste boxes and their role in the decay of the waste. Examination of the microbiome showed the presence of nematodes and fungal communities. The fungi species isolated were Aspergillus quadricinctus, Fusarium oxysporum, Lecanicillium coprophilumi, Scedosporium boydii, Scytalidium lignicola, Xenoacremonium recifei, and Pleurostoma richardsiae. These microorganisms showed a significant capacity to digest cellulose in our trials, which could be one of the ways they survive in such a harsh environment, reducing the volume of radioactive paper waste. These metabolic abilities give us a future perspective of using these fungi in biotechnology to remediate radioactively contaminated materials, particularly cellulose-based waste.

    Palavras-Chave: radiation accidents; cesium 137; waste management; fungi; radioactive wastes; brazil

  • IPEN-DOC 29634

    MATIATOS, IOANNIS; ARAGUAS-ARAGUAS, LUIS; WASSENAAR, LEONARD I.; MONTEIRO, LUCILENA R. ; HARJUNG, ASTRID; DOUENCE, CEDRIC; KRALIK, MARTIN. Nitrate isotopes reveal N-cycled waters in a spring-fed agricultural catchment. Isotopes in Environmental and Health Studies, v. 59, n. 1, p. 27-47, 2023. DOI: 10.1080/10256016.2022.2157412

    Abstract: Nitrate stable isotopes provide information about nitrate contamination and cycling by microbial processes. The Fischa-Dagnitz (Austria) spring and river system in the agricultural catchment of the Vienna basin shows minor annual variance in nitrate concentrations. We measured nitrate isotopes (δ15N, δ18O) in the source spring and river up to the confluence with the Danube River (2019–2020) with chemical and water isotopes to assess mixing and nitrate transformation processes. The Fischa-Dagnitz spring showed almost stable nitrate concentration (3.3 ± 1.0 mg/l as NO3–-N) year-round but surprisingly variable δ15N, δ18O-NO3– values ranging from +5.5 to +11.1‰ and from +0.5 to +8.1‰, respectively. The higher nitrate isotope values in summer were attributed to release of older denitrified water from the spring whose isotope signal was dampened downstream by mixing. A mixing model suggested denitrified groundwater contributed > 50 % of spring discharge at baseflow conditions. The isotopic composition of NO3– in the gaining streams was partly controlled by nitrification during autumn and winter months and assimilation during the growing season resulting in low and high δ15N-NO3– values, respectively. NO3– isotope variation helped disentangle denitrified groundwater inputs and biochemical cycling processes despite minor variation of NO3– concentration.

    Palavras-Chave: agriculture; biogeochemistry; denitrification; ground water; mixing; hydrology; isotopes; nitrogen 15; nitrates; oxygen 18

  • IPEN-DOC 29633

    RAMON, MAURO; RIBEIRO, ANDREZA P.; THEOPHILO, CAROLINA Y.S. ; MOREIRA, EDSON G. ; CAMARGO, PLINIO B. de; PEREIRA, CARLOS A. de B.; SARAIVA, ERLANDSON F.; TAVARES, ARMANDO dos R.; DIAS, ANTONIO G.; NOWAK, DAVID; FERREIRA, MAURICIO L.. Assessment of four urban forest as environmental indicator of air quality: a study in a brazilian megacity. Urban Ecosystems, v. 26, n. 1, p. 197-207, 2023. DOI: 10.1007/s11252-022-01296-7

    Abstract: Vehicular emissions comprise a main source of air pollutants, especially particulate matter (PM), which contains toxic compounds. Brazil has been restricting vehicular emissions for more than 30 years to minimize the impacts of fleet vehicles, but despite the restrictive legislation, several Brazilian cities still suffer from the effects of atmospheric pollution. The adoption of nature-based solutions (NbS) is being hailed as a sound alternative for improving urban air quality. In this sense, trees are a true reflection of the NbS concept since they can directly decrease PM levels by intercepting and resuspending particles, as well as altering pollution dispersion patterns. We wanted to understand the practical outcome of urban forest fragments as an NbS. Therefore, using litterfall in urban forest fragments, this study reported the role of green areas in reducing air pollution concentrations in 4 urban parks in Sao Paulo Megacity, Brazil. Air contaminants (Cd, Cu and Pb) varied from the edge to the core of urban forests. Multivariate analysis revealed that areas with different vehicle fleets influenced the input of air pollutants into these forest fragments. Our study further showed that trees serve as a natural barrier against PM. It can be concluded that this low-cost NbS alternative can reduce air pollution and has a potential to improve human health and well-being, and should be incorporated into municipal policies and programs, especially in critical locations of high human density. and poorly managed green areas.

    Palavras-Chave: urban areas; forests; environmental policy; planning

  • IPEN-DOC 29632

    SOUZA, VIVIANE C. de; RAMOS, GABRIEL dos S.; LEITE, JULIANA L.; SANTOS, MAURICIO B. dos; OTUBO, LARISSA ; CAMARGO, ZAINE T.; VICTOR, MAURICIO M.. A new thioglycolic ester β-cyclodextrin/PdCl2 in water: an accessible catalyst for the Suzuki-Miyaura coupling reaction. Carbohydrate Polymers, v. 301, n. Part A, p. 1-10, 2023. DOI: 10.1016/j.carbpol.2022.120271

    Abstract: A novel, easily prepared and accessible water-soluble supramolecular catalyst for the Suzuki-Miyaura Csingle bondC coupling reaction was synthesized and characterized by FTIR, NMR, XRD, SEM, and HR-TEM. An inexpensive Pd(II) source added to the resulting aqueous solution of thioglycolic ester β-cyclodextrin (1-TGA-SH-β-CD/PdCl2) showed Pd nanoclusters and efficient catalytic activity for Suzuki-Miyaura Csingle bondC coupling reactions of aryl halides with aryl boronic acids, employing K2CO3 as base, in an environmentally benign aqueous solution prepared in open flasks. Organic aryl halides including chlorides can produce moderate to excellent yields with aryl boronic acids and a small catalytic amount (0.01 mol%) of 1-TGA-SH-β-CD/PdCl2. This hydro-soluble catalyst stock solution was stable for long periods (more than three months) and could be reused in two runs until showing loss of catalytic activity. Some experiments to understand the mechanism were performed, with the results suggesting incorporation of aryl halide in the catalytic cavity.

    Palavras-Chave: thiols; dextrin; catalysts; palladium complexes; halides; aqueous solutions; aqueous solutions

  • IPEN-DOC 29631

    ANTUNES, PAULA C.G. ; SIQUEIRA, PAULO de T.D. ; SHORTO, JULIAN M.B. ; YORIYAZ, HELIO . A versatile physical phantom design and construction for I-125 dose measurements and dose-to-medium determination. Brachytherapy, v. 22, n. 1, p. 80-92, 2023. DOI: 10.1016/j.brachy.2022.10.005

    Abstract: PURPOSE: In this paper we present a phantom designed to provide conditions to generate set of “true” independent reference data as requested by TG-186, and mitigating the scarcity of experimental studies on brachytherapy validation. It was used to perform accurate experimental measurements of dose of 125I brachytherapy seeds using LiF dosimeters, with the objective of experimentally validating Monte Carlo (MC) calculations with model-based dose calculation algorithm (MBDCA). In addition, this work intends to evaluate a methodology to convert the experimental values from LiF into dose in the medium. METHODS AND MATERIALS: The proposed PMMA physical phantom features cavities to insert a LiF dosimeter and a 125I seed, adjusted in different configurations with variable thickness. Monte Carlo calculations performed with MCNP6.2 code were used to score the absorbed dose in the LiF and the dose conversion parameters. A sensitivity analysis was done to verify the source of possible uncertainties and quantify their impact on the results. RESULTS: The proposed phantom and experimental procedure developed in this work provided precise dose data within 5.68% uncertainty (k = 1). The achieved precision made it possible to convert the LiF responses into absorbed dose to medium and to validate the dose conversion factor methodology. CONCLUSIONS: The proposed phantom is simple both in design and as in its composition, thus achieving the demanded precision in dose evaluations due to its easy reproducibility of experimental setup. The results derived from the phantom measurements support the dose conversion methodology. The phantom and the experimental procedure developed here can be applied for other materials and radiation sources.

    Palavras-Chave: biological models; phantoms; brachytherapy; iodine 125; seeds; lithium fluorides; monte carlo method

  • IPEN-DOC 29630

    JESUS, JULIANA M.S. de; ARGOLO, ALLAN dos S.; TOMINAGA, FLAVIO K. ; TAQUEDA, MARIA E.; BILA, DANIELE M.; BORRELY, SUELI I. ; TEIXEIRA, ANTONIO C.S.C.. Experimental design and bioassays as tools to investigate the impact of anodic oxidation on progestins degradation. Water, v. 15, n. 1, p. 1-18, 2023. DOI: 10.3390/w15010061

    Abstract: The present study investigated the degradation of levonorgestrel (LNG) and gestodene (GES) through an anodic oxidation process mediated by active chlorine species. The independent variables [LNG]0 and [GES]0, current density (mA cm−2), and [NaCl]0 (mol L−1) were optimized through a response surface methodology (RSM) based on a four-level central composite design (CCD). Specific energy consumption allowed CCD-RSM analysis and optimization. The decay of progestins was followed to verify the kinetics of the anodic degradation process. Chlorine monitoring showed that excess Cl− concentration did not mean high hormones removal, as well as the excess of current density. Central point conditions ([NaCl]0 = 0.07 mol L−1, j = 32.5 mA cm−2, [LNG]0, and [GES]0 1.0 mg L−1) proved to be the best operational option. The performance with real pharmaceutical wastewater confirmed model optimization (2.2 ± 0.2 kWh g−1, with removals of 83.1 ± 0.9% and 75.1 ± 2.8% for LNG and GES, respectively). The selected condition was used for estrogenic activity and acute toxicity assays. The first allowed the identification of the initial estrogenic activity for the mixture of LNG and GES (924 E2-EQ ng L−1). Additionally, the electrochemical process could decrease this environmental parameter by 74.6%. The progestin mixture was classified as acute toxicity to Daphnia similis, with a toxicity unit (TU) of 2.5 100/EC50%. After electrolysis, the hormone solutions reached a fourfold increase in TU value, classified as high acute toxicity.

    Palavras-Chave: composite materials; design; progesterone; waste water; drugs; estrogens; hormones; water pollution

  • IPEN-DOC 29629

    MARCHIOLI, CARLOS A. ; ALMEIDA, GISELE F.C. ; GONCALVES, RODOLFO L.P.; XAVIER, MARCOS D.; SANTOS, GIVANILDO A. dos; COUTO, ANTONIO A. . Influência na microestrutura e propriedades mecânicas da liga de alumínio A380 fundida sob pressão pela variação nas velocidades de injeção / Influence in the microstructure and mechanical properties of the aluminum alloy A380 die casting by the injection speed steps. Tecnologia em Metalurgia, Materiais e Mineração, v. 20, p. 1-9, 2023. DOI: 10.4322/2176-1523.20222804

    Abstract: Na fundição sob pressão de ligas de alumínio, devido à alta velocidade de injeção do metal líquido no molde, obtém-se uma microestrutura com grãos refinados e possível ocorrência de defeitos como microporosidade e microrechupes. Esses defeitos podem ocorrer devido a deficiências no projeto do ferramental, na definição dos parâmetros de cálculo ou mesmo no controle dos parâmetros de injeção. O objetivo deste trabalho é analisar a influência das velocidades das fases de injeção (primeira e segunda fases) na microestrutura e propriedades mecânicas da liga de alumínio A380. Corpos de prova foram moldados sob pressão de matriz em uma máquina de injeção de câmara fria. A faixa de velocidade de injeção do processo foi de 0,10 m/s, 0,25 m/s e 0,50 m/s para a primeira fase, e 0,6 m/s, 1,5 m/s 3,0 m/s para a segunda fase. As propriedades mecânicas foram determinadas por meio de ensaios de tração e dureza e a caracterização microestrutural por microscopia óptica. Os resultados indicaram que a velocidade de injeção não influencia o limite de resistência tanto da primeira quanto da segunda fase de injeção. No entanto, o nível de porosidade e erros de execução mudaram em função das variações de velocidade, fatores que afetam o resultado do alongamento e limite de escoamento dos produtos de fundição sob pressão.

    Palavras-Chave: castings; hardness; tensile properties; aluminium alloys; microstructure

  • IPEN-DOC 29628

    CAIXETA, DOUGLAS C.; LIMA, CASSIO ; XU, YUN; GUEVARA-VEGA, MARCO; ESPINDOLA, FOUED S.; GOODACRE, ROYSTON; ZEZELL, DENISE M. ; SABINO-SILVA, ROBINSON. Monitoring glucose levels in urine using FTIR spectroscopy combined with univariate and multivariate statistical methods. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, v. 290, p. 1-9, 2023. DOI: 10.1016/j.saa.2022.122259

    Abstract: The development of novel platforms for non-invasive continuous glucose monitoring applied in the screening and monitoring of diabetes is crucial to improve diabetes surveillance systems. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy of urine can be an alternative as a sustainable, label-free, fast, non-invasive, and highly sensitive analysis to detect changes in urine promoted by diabetes and insulin treatment. In this study, we used ATR-FTIR to evaluate the urinary components of non-diabetic (ND), diabetic (D), and diabetic insulin-treated (D + I) rats. As expected, insulin treatment was capable to revert changes in glycemia, 24-h urine collection volume, urine creatinine, urea, and glucose excretion promoted by diabetes. Several differences in the urine spectra of ND, D, and D + I were observed, with urea, creatinine, and glucose analytes being related to these changes. Principal components analysis (PCA) scores plots allowed for the discrimination of ND and D + I from D with an accuracy of ∼ 99 %. The PCA loadings associated with PC1 confirmed the importance of urea and glucose vibrational modes for this discrimination. Univariate analysis of second derivative spectra showed a high correlation (r: 0.865, p < 0.0001) between the height of 1074 cm-1 vibrational mode with urinary glucose concentration. In order to estimate the amount of glucose present in the infrared spectra from urine, multivariate curve resolution-alternating least square (MCR-ALS) was applied and a higher predicted concentration of glucose in the urine was observed with a correlation of 78.9 % compared to urinary glucose concentration assessed using enzyme assays. In summary, ATR-FTIR combined with univariate and multivariate chemometric analyses provides an innovative, non-invasive, and sustainable approach to diabetes surveillance.

    Palavras-Chave: diabetes mellitus; fourier transform spectrometers; infrared spectra; urine; biological markers; quantitative chemical analysis; glucose

  • IPEN-DOC 29627

    TOMINAGA, FLAVIO K. ; BOIANI, NATHALIA F. ; SILVA, THALITA T. ; SANTOS, JONAS G. dos; LEBRE, DANIEL T. ; LEO, PATRICIA; BORRELY, SUELI I. . Electron beam irradiation applied for the detoxification and degradation of single ciprofloxacin aqueous solution and multiclass pharmaceutical quaternary mixture. Separation and Purification Technology, v. 307, p. 1-9, 2023. DOI: 10.1016/j.seppur.2022.122818

    Abstract: The application of electron beam irradiation for detoxification and degradation of single antibiotic ciprofloxacin (CPF) and in a mixture with multiclass pharmaceuticals in aqueous solutions was carried out. Ecotoxicity assays indicated that the green algae were most sensitive to antibiotic and also that the presence of several pharmaceutical increased the toxicity. After the irradiation treatment, degradation results of single antibiotic indicated reduction of 95.86 % at 1.0 kGy. Total organic carbon decreased up to 38 % at 5.0 kGy. At lower doses (1.0 kGy), no effect in toxicity was evidenced, however, increase in toxicity for Vibrio fischeri was observed after 2.5 kGy. For Daphnia similis exposure, an increase in toxicity was noted for all applied doses. In contrast, for the green algae R. subcapitata toxicity reduction varied from 62.3 to 81.9 % at the evaluated doses. Toxicity assays to microbes E. coli and S. aureus reduced antibacterial activity of CPF after irradiation treatment. Regarding the irradiated quaternary mixture at 2.5 kGy, reduction up to 96 % was achieved for the ciprofloxacin, metformin and acetylsalicylic acid, and 81 % removal was achieved for fluoxetine. Acute assays with V. fischeri indicated no increase in toxicity, while some increase was noted for D. similis (acute effects). Nevertheless, chronic assays data indicated low toxicity reduction (14 %) with D. similis, and complete detoxification was shown for the green algae after the irradiation. In addition, decrease in antimicrobial activity was noted after the treatment. Furthermore, the in-silico model was not enough accurate for the prediction of CIP toxicity. These findings showed that electron beam irradiation can be applied for reducing the impacts of antibiotics in aquatic ecosystem. Measuring toxicity on living-organism from different trophic levels are useful tools to evaluate the interaction of mixtures and also to assess toxicity of the generated byproducts.

    Palavras-Chave: electron beams; antibiotics; toxicity; drugs; water pollution; water treatment; irradiation

  • IPEN-DOC 29626

    XIAO, DA; WANG, NANCHAO; CHEN, SIJIE; WU, LINGYUN; MULLER, DETLEF; VESELOVSKII, IGOR; LI, CHENGCAI; LANDULFO, EDUARDO ; SIVAKUMAR, VENKATARAMAN; LI, JING; CHE, HUIZHENG; FANG, JING; ZHANG, KAI; WANG, BINYU; CHEN, FEITONG; HU, XIANZHE; LI, XIAOTAO; LI, WEIZE; TONG, YICHENG; KE, JU; WU, LAN; LIU, CHONG; LIU, DONG. Simultaneous profiling of dust aerosol mass concentration and optical properties with polarized high-spectral-resolution lidar. Science of the Total Environment, v. 872, p. 1-13, 2023. DOI: 10.1016/j.scitotenv.2023.162091

    Abstract: Dust particles originating from arid desert regions can be transported over long distances, presenting severe risks to climate, environment, social economics, and human health at the source and downwind regions. However, there has been a dearth of continuous diurnal observations of vertically resolved mass concentration and optical properties of dust aerosols, which hinders our understanding of aerosol mixing, stratification, aerosol-cloud interactions, and their impacts on the environment. To fill the gap of the insufficient observations, to the best of our knowledge, this work presents the first high-spectral-resolution lidar (HSRL) observation providing days of continuous profiles of the mass concentration, along with particle linear depolarization ratio (PLDR), backscattering coefficient, extinction coefficient and lidar ratio (LR), simultaneously. We present the results of two strong dust events observed by HSRL over Beijing in 2021. The maximum particle mass concentrations reached (1.52 ± 3.5) x103 μg/m3 and (19.48 ± 0.36) x103 μg/m3 for the two dust events, respectively. The retrieved particle mass concentrations and aerosol optical depth (AOD) agree well with the observation from the surface PM10 concentrations and sun photometer with correlation coefficients of 0.90 and 0.95, respectively. The intensive properties of PLDR and LR of the dust aerosols are 0.31 ± 0.02 and 39 ± 7 sr at 532 nm, respectively, which are generally close to those obtained from observations in the downwind areas. Moreover, inspired by the observations from HSRL, a universal analytical relationship is discovered to evaluate the proportion of dust aerosol backscattering, extinction, AOD, and mass concentration using PLDR. The universal analytical relationship reveals that PLDR can directly quantify dust aerosol contribution, which is expected to further expand the application of polarization technology in dust detection. These valuable observations and findings further our understanding of the contribution of dust aerosol to the environment and help supplement dust aerosol databases.

    Palavras-Chave: dusts; aerosols; particles; optical radar; environmental impacts

  • IPEN-DOC 29625

    SPATAFORA, A.; CARBONE, D.; CAPPUZZELLO, F.; CAVALLARO, M.; ACOSTA, L.; AGODI, C.; AMADOR-VALENZUELA, P.; BORELLO-LEWIN, T.; BRISCHETTO, G.A.; CALABRESE, S.; CALVO, D.; CAPIROSSI, V.; CHAVEZ LOMELI, E.R.; CIRALDO, I.; DE GREGORIO, G.; DELAUNAY, F.; DJAPO, H.; EKE, C.; FINOCCHIARO, P.; FIRAT, S.; FISICHELLA, M.; FOTI, A.; GARGANO, A.; HACISALIHOGLU, A.; IAZZI, F.; LA FAUCI, L.; LINARES, R.; LUBIAN, J.; MEDINA, N. ; MORALLES, M. ; OLIVEIRA, J.R.B.; PAKOU, A.; PANDOLA, L.; PETRASCU, H.; PINNA, F.; RUSSO, G.; SGOUROS, O.; SILVEIRA, M.A.G. da; SOLAKCI, S.O.; SOUKERAS, V.; SOULIOTIS, G.; TORRESI, D.; TUDISCO, S.; YILDIRIM, A.; ZAGATTO, V.A.B.. Multichannel experimental and theoretical approach to the 12C(18O, 18F)12B single-charge-exchange reaction at 275 MeV: initial-state interaction and single-particle properties of nuclear wave functions. Physical Review C, v. 107, n. 2, p. 024605-1 - 024605-19, 2023. DOI: 10.1103/PhysRevC.107.024605

    Abstract: Background: Single-charge-exchange reactions are appropriate tools to study the nuclear response to one-particle/one-hole isospin probes, gaining additional interest from the connection to beta decay. This analogy has been recently extended to second order, connecting double-charge-exchange reactions and double beta decays. Nowadays, the availability of powerful experimental setups and advanced nuclear theories and models allows one to access precious information on key nuclear structure aspects embedded in the widely sought neutrinoless double beta decay. Purpose: We intend to bring to light the main nuclear structure and reaction features involved in the 18O+12C collision at 275 MeV incident energy. In this paper, the main focus is on the role of the initial- and final-state interactions in the overall reaction dynamics and on the single-particle nuclear structure properties accessed via the study of single-nucleon transfer reactions. Forthcoming articles will be devoted to go into the details of the response to one- and two-particle/hole isospin probes. Methods: Cross-section energy spectra and angular distributions were measured in a unique experimental setup for the 12C(18O, 18O)12C elastic and inelastic scattering, the 12C(18O, 17O)13C one-neutron stripping, the 12C(18O, 19F)11B one-proton pickup, and the 12C(18O, 18F)12B single-charge-exchange nuclear reactions. A unique comprehensive and coherent theoretical calculation, able to describe the whole network of direct reactions using state-of-the-art nuclear structure and reaction theories, was performed, and it is presented for the first time in this article. This holistic approach, applied both to the experimental and theoretical analysis, is the main feature and worth of the work here presented. Results: The energy and angular resolutions achieved in each reaction channel allowed us to isolate specific transitions and to map the diffraction patterns in the angular distributions. The cross-section calculations describe well the experimental data, both in terms of the absolute values and diffraction patterns. Although the distorted wave Born approximation (DWBA) calculations prove to be accurate in describing all the studied channels, better results are achieved when the couplings to inelastic transitions in both the incoming and outgoing partitions are introduced, as done in the coupled channels Born approximation (CCBA) calculations. Otherwise, no real improvement is found when the coupling effects among different partitions are explicitly taken into account in the coupled reaction channels (CRC) calculations. Conclusions: The multichannel approach proposed in this paper is a promising method for accurate investigations of direct reactions originating in heavy-ion collisions. This is quite appealing for the precise spectroscopy of heavy nuclei proposed in many areas of nuclear physics. An example is the NUMEN project with its challenging commitment to provide valuable information on neutrinoless double beta decay nuclear matrix elements from single- and double-charge-exchange cross-section measurements.

    Palavras-Chave: nuclear matrix; charge-exchange reactions; excitation; wave functions; multi-channel analyzers

  • IPEN-DOC 29624

    ANDRADE, MAIRA F. ; SARDO, ARIANE V.N. ; BENETTI, CAROLINA ; SICCHIERI, LETICIA B. ; CORREA, LUCIANA; ZEZELL, DENISE M. . Comparison of two light wavelengths (λ = 660 nm and λ = 780 nm) in the repair process of oral mucositis induced by ionizing radiation: clinical and microscopic evaluations in rats. Photonics, v. 10, n. 1, p. 1-13, 2023. DOI: 10.3390/photonics10010016

    Abstract: Photobiomodulation (PBM) has been clinically used for the prevention and treatment of oral mucositis (OM). The effect of red and near-infrared wavelengths on OM repair is still misunderstood. The aim of this study was to compare the clinical effect and tissue changes caused by 660 nm and 780 nm exposure in an experimental model of OM. Rats were submitted to gamma irradiation for induction of OM lesions and treated with 660 nm or 780 nm lasers with the same dosimetry parameters (30 mW, 7.5 J/cm2, 10 s, spot size = 0.04 mm, irradiation every two days). Clinical assessment of OM severity and histopathological analyses was performed after 8, 14, and 20 days of the ionizing radiation. OM severity was reduced in the PBM groups, especially when the red laser was used. The histopathological pattern was similar between the PBM groups, showing advanced re-epithelization and more pronounced angiogenesis and collagen deposition compared to the control. The 660 nm group showed a greater collagen matrix area than the 780 nm group at 14 days. In conclusion, PBM at 660 nm and 780 nm improved the repair of ionizing radiation-induced OM. Both wavelengths activated the angiogenesis and collagen deposition, but these tissue effects were more pronounced when 660 nm was used.

    Palavras-Chave: oral cavity; mucous membranes; injuries; radiotherapy; lasers; ionizing radiations

  • IPEN-DOC 29623

    NOVAES, G.A.; BLANK, M.H.; YOSHIMURA, T.M. ; RIBEIRO, M.S. ; PEREIRA, R.J.G.. Methylene blue-mediated antimicrobial photodynamic therapy on chicken semen. Photodiagnosis and Photodynamic Therapy, v. 41, p. 1-12, 2023. DOI: 10.1016/j.pdpdt.2023.103290

    Abstract: Background: Artificial insemination is widely employed in poultry, but high degrees of bacterial contamination are often observed in semen because of its passage through the cloaca. Consequently, most semen extenders for birds have antibiotics that could aggravate bacterial resistance. Methods: We evaluated the potential of antimicrobial photodynamic therapy (PDT) as an alternative to the use of antibiotics, and assessed whether changes in concentration and incubation time with methylene blue (MB), radiant exposure, and irradiance of light affect spermatozoa activity and bacteria in chicken semen. Results: Incubation with MB (< 25 µM) did not alter sperm motility, regardless of the pre-irradiation time (PIT, 1 or 5 min). Following 1 min of PIT with MB at 10 µM, samples were irradiated for 30, 60, 120, and 180 s at irradiances of 44, 29, and 17 mW/ cm² (660 nm LedBox). MB and light alone did not interfere with the analyzed parameters. However, when both factors were associated, increases in light dose led to greater reductions in sperm parameters, regardless of the irradiance used. Besides, PDT conditions that were less harmful to spermatozoa were not able to significantly reduce bacterial colonies in chicken semen. Conclusions: A failure in MB selectivity could explain unsuccessful bacterial reduction following PDT. Further research involving other photosensitizers or conjugating molecules to MB to target microbial cells is needed for PDT application in poultry breeders.

    Palavras-Chave: fowl; antibiotics; reproduction; microorganisms; chickens; photodynamic therapy

  • IPEN-DOC 29622

    PACOMPIA, YOLANDA; SUPO-RAMOS, JUSTO G.; GONZALES-LORENZO, CARLOS D.; CALLO-ESCOBAR, DARWIN J.; ROCCA, RENE R.; PASTRANA, ELIZABETH C.; GOMES, MONISE B. ; SILVA-CARRERA, BETZABEL N. ; WATANABE, S.; AYCA-GALLEGOS, OSCAR; AYALA-ARENAS, JORGE S.. Luminescence dating and firing temperature determination of ancient ceramics fragments from the Tunata-hill site in the Churajon archaeological complex in Arequipa, Peru. Radiation Physics and Chemistry, v. 204, p. 1-11, 2023. DOI: 10.1016/j.radphyschem.2022.110725

    Abstract: Ancient pottery fragments from the Tunata-hill site in Churajon archaeological complex, Arequipa, Peru, were dated by means of luminescence techniques such as thermoluminescence (TL) and optically stimulated luminescence (OSL) in order to provide absolute chronology. For TL, additive and regenerative methods were performed. For OSL a regenerative method was carried out for IRSL dating. A rigorous description of the study area and its context has been made. The ages of the samples were found to be between 0.50 ± 0.06 ky and 0.49 ± 0.03 ky for TL methods, and 0.49 ± 0.02 ky for OSL methods. On average, the estimated age by TL and OSL techniques is 490 ± 70 yr (1600 AD and 1460 AD). This means that Churajon ceramics under study would belong to the Late periods which corresponds to the Inca region, and the North sub-region of the Late Churajon phase, and the beginning of European colonization in Peru. X-ray fluorescence technique (XRF) analysis has shown the main presence of Fe (39.5%), Si (30.0%), and Al (10.4%) in fine pottery powder. Furthermore, the electron paramagnetic resonance (EPR) technique was used to study the firing temperature using the iron signal (Fe3+) as a firing temperature reference. The firing temperature of ceramics was found to be around 550 ± 50 °C.

    Palavras-Chave: ceramics; archaeological sites; thermoluminescence; age estimation; temperature dependence; photoluminescence; x-ray fluorescence analysis; cultural objects

  • IPEN-DOC 29621

    PRADO, FELIPE M. ; FRANCO, TOMAS J. ; WETTER, NIKLAUS U. . Sub-nanosecond, 41 mJ pulse energy, passively Q-switched Nd:YLF laser. Optics and Laser Technology, v. 162, p. 1-6, 2023. DOI: 10.1016/j.optlastec.2023.109257

    Abstract: A sub-nanosecond, diode-stack side-pumped, passively Q-switched Nd3+:YLF4/Cr4+:YAG Laser is reported in a compact cavity design, generating one pulse of 41 mJ with a pulse width of 894 ps, achieving a peak output power of 46 MW and beam quality M2 of 5.4 × 5.9 (HxV). The number of pulses in the pulse train could be adjusted from one pulse to ten pulses of 111 mJ total output energy and 23.7 % optical efficiency by adjusting the focus distance while maintaining sub-nanosecond pulse duration. This resonator can also be used for high-power simultaneous Q-switched laser emission at 1047 nm and 1053 nm.

    Palavras-Chave: q-switching; high energy physics; crystals; pumping

  • IPEN-DOC 29620

    AVELAR, ALAN M.; CAMARGO, FABIO de; SILVA, VANESSA S.P. da; GIOVEDI, CLAUDIA ; ABE, ALFREDO ; MOURAO, MARCELO B.. Effectiveness of Ni-based and Fe-based cladding alloys in delaying hydrogen generation for small modular reactors with increased accident tolerance. Nuclear Engineering and Technology, v. 55, n. 1, p. 156-168, 2023. DOI: 10.1016/

    Abstract: This study investigates the high temperature oxidation behaviour of a Ni–20Cr-1.2Si (wt.%) alloy in steam from 1200 °C to 1350 °C by Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD). The results demonstrate that exposed Ni-based alloy developed a thin oxide scale, consisted mainly of Cr2O3. The oxidation kinetics obtained from the experimental results was applied to evaluate the hydrogen generation considering a simplified reactor core model with different cladding alloys following an unmitigated Loss-Of-Coolant Accident (LOCA) scenario in a hypothetical Small Modular Reactor (SMR). Overall, experimental data and simulations results show that both Fe-based and Ni-based alloys may enhance cladding survivability, delaying its melting, as well as reducing hydrogen generation under accident conditions compared to Zr-based alloys. However, a substantial neutron absorption occurs when Ni-based alloys are used as cladding for current uranium-dioxide fuel systems, even when compared to Fe-based alloys.

    Palavras-Chave: fuel-cladding interactions; nickel alloys; stainless steels; oxidation; temperature range 0400-1000 k; cladding

  • IPEN-DOC 29619

    BORDON, CAMILA D. da S.; DIPOLD, JESSICA ; WETTER, NIKLAUS U. ; ROSSI, WAGNER de ; FREITAS, ANDERSON Z. ; KASSAB, LUCIANA R.P.. Effect of silver nanoparticles on the optical properties of double line waveguides written by fs laser in Nd3+-doped GeO2-PbO glasses. Nanomaterials, v. 13, n. 4, p. 1-13, 2023. DOI: 10.3390/nano13040743

    Abstract: Nd3+-doped GeO2-PbO glass with silver (Ag) nanoparticles (NPs) are produced with double line waveguides through fs laser processing for photonic applications. A Ti:sapphire fs laser at 800 nm was used to write the waveguides directly into the glass 0.7 mm beneath the surface. This platform is based on pairs of parallel lines with spacing of 10 µm, each pair being formed by two identical written lines but in two different configurations of 4 or 8 separately processed lines, which are coincident. The results of optical microscopy, absorbance measurements, refractive index change, beam quality factor (at 632 and 1064 nm), photoluminescence, propagation losses, and relative gain at 1064 nm are presented. The structural changes in the glass due to the presence of Ag NPs were investigated by Raman spectroscopy. At 632 and 1064 nm, x,y-symmetrical guiding was observed, and for both kinds of overlapping pulses, a refractive index alteration of 10−3 was found in both directions. Photoluminescence growth of ~47% at 1064 nm was observed due to the plasmonic effect of Ag NPs. In dual waveguides containing Ag NPs, the relative gain obtained increased by 40% and 30% for four and eight overlapping lines, respectively, at 600 mW of 808 nm pump power, when compared to waveguides without those metallic NPs. We highlight the resultant positive internal gains of 5.11 and 7.12 dB/cm that showed a growth of ~40% and ~30%, respectively, with respect to the samples without Ag NPs. The increase in photoluminescence and relative gain were related to the local field growth produced by Ag NPs. The present results show that the addition of Ag NPs impacts positively on the optical performance at 1064 nm of double line waveguides processed by fs laser writing in Nd3+-doped GeO2-PbO glass, opening news perspectives for photonics.

    Palavras-Chave: lasers; pulses; germanates; waveguides; optical equipment; silver; nanoparticles

  • IPEN-DOC 29618

    MACHADO, ARTHUR P. ; CARMINATI, SAULO A. ; JANUARIO, ELIANE R. ; FERREIRA, PATRICIA S. ; VAZ, JORGE M. ; SPINACE, ESTEVAM V. . Photocatalytic methane conversion over Pd/ZnO photocatalysts under mild conditions. Methane, v. 2, n. 1, p. 44-55, 2023. DOI: 10.3390/methane2010003

    Abstract: Here, Pd nanoparticles supported on ZnO were prepared by the alcohol-reduction and the borohydride-reduction methods, and their efficiency towards the photocatalytic conversion of methane under mild conditions were evaluated. The resulting Pd/ZnO photocatalysts were characterized by X-ray fluorescence, X-ray diffraction, X-ray photoelectron spectroscopy, UV–Vis, and transmission electron microscopy. The reactions were performed with the photocatalysts dispersed in water in a bubbling stream of methane under UV-light illumination. The products formed were identified and quantified by gas chromatography (GC-FID/TCD/MSD). The principal products formed were C2H6 and CO2 with minor quantities of C2H4 and CO. No H2 production was observed. The preparation methods influenced the size and dispersion of Pd nanoparticles on the ZnO, affecting the performance of the photocatalysts. The best performance was observed for the photocatalyst prepared by borohydride reduction with 0.5 wt% of Pd, reaching a C2H6 production rate of 686 µmol·h−1·g−1 and a C2H6 selectivity of 46%.

    Palavras-Chave: photocatalysis; methane; zinc oxides; palladium; nanoparticles

  • IPEN-DOC 29617

    SILVA, DANIEL J. da; FERREIRA, GREICIELE S.; DURAN, ADRIANA; FONSECA, FERNANDO L.A.; PARRA, DUCLERC F. ; BUENO, RODRIGO F.; ROSA, DERVAL S.. Copper coatings on poly(lactic acid) via rapid magnetron sputtering: morphology, chemistry, and antimicrobial performance against bacteria and SARS-CoV-2. Materials Today Communications, v. 34, p. 1-13, 2023. DOI: 10.1016/j.mtcomm.2023.105440

    Abstract: Materials with antimicrobial properties are highly desirable for making food packaging and personal protective equipment due to their intrinsic ability to prevent the proliferation of pathogenic microorganisms and food contamination. Poly(lactic acid) (PLA) is a biodegradable, compostable, and recyclable polymer that presents interesting mechanical properties for such applications. However, this polymer does not show intrinsic antimicrobial activity. Herein, we applied Radio Frequency Magnetron Sputtering (RF-MS) to produce antimicrobial copper coatings on the PLA surface. The results indicate that the prolongation in the copper deposition time causes an increase in surface roughness. The PLA coating with copper using a short deposition time (5–20 s) was sufficient to guarantee a bactericidal effect against Escherichia coli and Bacillus subtilis, in addition to conferring antiviral activity against Omicron Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Nuclear magnetic resonance (NMR) and high-resolution x-ray photoelectron (XPS) spectroscopic studies indicate that occurs only localized degradation on the PLA surface via polymer chain scission. The RF-MS technique was suitable for rapidly manufacturing antimicrobial Cu-coated PLA and providing low copper consumption in the antimicrobial coating process.

    Palavras-Chave: coronaviruses; polymers; lactic acid; copper; plasma; coatings; antimicrobial agents

  • IPEN-DOC 29616

    KIM, BIANCA S.M.; AMORIM, EDUARDO P. ; SILVA, PAULO S.C. ; FIGUEIRA, RUBENS, C.L.; BRAGA, ELISABETE S.; FAVARO, DEBORAH I.T. . Vintage analysis on superficial sediments to predict future trends in metal contamination of Santos and São Vicente Estuarine System. Journal of Trace Elements and Minerals, v. 3, p. 1-8, 2023. DOI: 10.1016/j.jtemin.2023.100049

    Abstract: Due to its economic, social, and environmental importance, Santos and São Vicente Estuarine System is largely studied for almost two decades. Although many studies have been conducted, none of them tried to relate past activities to actual ones. This study provides an evaluation of the contamination on vintage superficial sediment samples investigating sediment contamination patterns over the years to help to understand future trends in metal contamination in this area. Thus, this study aims to assess levels of trace elements and rare earth elements (REEs) on samples collected in two seasonal periods of 2005 and 2006 (summer and winter). In each campaign, 16 surface samples were collected onboard R/V Veliger II, and trace elements and REEs were analyzed by neutron activation analysis. Results of metals presented similar levels over the years and it was not related to the port's activities since the levels did now increase following the total movement of containers. In addition, the enrichment of light REEs could indicate anthropogenic activities from steel plants, phosphate fertilizers, and the phosphogypsum piles. The system undergoes through many human pressures and constant monitoring over time it is important to avoid overloading the resilience capacity of the estuarine system because the expansion of port, industry, and urbanization is inevitable. From the results obtained, it was possible to conclude that SSVES undergoes more likely anthropogenic pressures from industrial activities and domestic effluents rather than port activity.

    Palavras-Chave: economic analysis; estuaries; water pollution; sediments; trace amounts; elements

  • IPEN-DOC 29615

    RIBEIRO, I.L.F.; CARVALHO, G.L.; DIB, L.F.G.; BARBOSA, E.A.; WETTER, N.U. . Vibration amplitude mapping by stroboscopic structured light projection. Optics Communications, v. 531, p. 1-9, 2023. DOI: 10.1016/j.optcom.2022.129219

    Abstract: In this work a method to evaluate the distribution of vibration amplitudes of objects was demonstrated, combining for the first time oblique structured light projection, stroboscopic illumination and fringe evaluation. The light pattern was formed by straight and parallel fringes produced by a slightly misaligned Twyman–Green interferometer illuminated by a 40-mW, 650-nm diode laser. Stroboscopic illumination was achieved by driving the laser with a PWM signal with the same frequency than that of the vibrating object. By evaluating the fringes with phase stepping and phase unwrapping procedures, the amplitude mapping of a formica bar and circular rubber membranes was performed. By averaging the fringe position over the light pulse duration a correction ratio between the actual phase and the measured phase was obtained as a function of the pulse duty cycle, and the dependence of the fringe visibility on the duty cycle was studied. The experiments showed that relatively large amplitudes in a range from tens of millimeters up to few millimeters can be measured.

    Palavras-Chave: optical equipment; evaluation; vibrational states; mechanical vibrations

  • IPEN-DOC 29614

    MELO, A.D.; SILVA, J.P. da; NOBRE, F.X.; COSTA, S.; SALES JUNIOR, J.C.C.; ANGLADA-RIVERA, J.; GUERRERO, F.; PAULA, M.M. da S.; SOUZA, R.F.B. de ; PENA-GARCIA R.; AGUILERA, L.; LEYET, Y.. Synthesis microwave-assisted: fast method to obtain lithium-doped sodium titanate. Journal of Materials Science: Materials in Electronics, v. 34, n. 6, p. 1-10, 2023. DOI: 10.1007/s10854-023-09948-w

    Abstract: In this work, the variation in the structural and electrical properties of lithium-doped sodium titanate, obtained from an ultrafast (15 min) microwave-assisted synthesis has been reported. X-ray diffraction and Rietveld analysis have been done to identify the present phases, their composition, and lattice parameters. Na2Ti3O7 was identified as the major phase, while Na2Ti6O13 was obtained as a secondary phase in all samples. The phase composition usually varies depending on the content of the doping element. In the sample with 0.5% lithium ions, an additional phase corresponding to NaLiTi3O7 appeared. The microstructure of the ceramic samples showed an increase in the grains size and the appearance of small particles on the surface of the grains. This effect becomes more evident for the samples with 0.5% Li. Finally, the electrical properties of the ceramic samples studied were favored with an increase in doping and σdc values of 1.94 × 10− 5 S cm− 1, 2.51 × 10− 5 S cm− 1, and 4.00 × 10− 5 S cm− 1 were determined for Na2 − xLixTi3O7 with x = 0.0%, 0.1%, 0.5% of Li+.

    Palavras-Chave: sodium compounds; titanates; microwave radiation; lithium; doped materials

  • IPEN-DOC 29613

    PACHECO, CAROLINE V.; PERES, RENATO M.; CARRIERI, GABRIELA; MINUSSI, GIULIA R.; ZAMBRANA, GUIDO P.; KANG, JESSICA S.H.; OLIVEIRA, RENE R. de ; LIMA, NELSON B. de ; BERNUSSI, AYRTON; WARZYWODA, JULIUSZ; MUNHOZ, ANTONIO H.. Cement-based composites incorporating pseudoboehmite nanomaterials. Journal of Materials in Civil Engineering, v. 35, n. 2, p. 04022413-1 - 04022413-11, 2023. DOI: 10.1061/(ASCE)MT.1943-5533.0004586

    Abstract: Pseudoboehmite is a hydrated aluminum oxyhydroxide obtained from inorganic precursors by the sol-gel process. It is used as a precursor to alumina and as a reinforcement in obtaining nanocomposites. Cement-reinforced composites with this nanomaterial were obtained in concrete and mortar. Pseudoboehmite with sodium polyacrylate was used to promote a deflocculation of pseudoboehmite particles, which tend to agglomerate in the material. The obtained material was added to the concrete to improve its workability and strength. The new concrete was characterized by slump tests and mechanical tests. Our results revealed that the incorporation of pseudoboehmite with sodium polyacrylate significantly increased the compressive strength and improved the workability of the concrete. Multiple experiments evaluated compressive strength, ultrasound speed, and nanomaterial characterization. Using the Weibull method in mortars, we verified that the pseudoboehmite brought visible benefits as the characteristic stress increased by 17.5%. This increase was observed with the addition of 3% by weight of pseudoboehmite.

    Palavras-Chave: nanomaterials; aluminium compounds; building materials; mortars; concretes; sodium; polyacrylates

  • IPEN-DOC 29612

    CANO, NILO F.; AYNAYA-CAHUI, SANDRA C.; VILCA, ZAIDA V.; ROCCA, RENE R.; GUNDU RAO, T.K.; CARRERA, BETZABEL N.S. ; LOPEZ-GONZALES, ALEJANDRO H.; JAVIER-CCALLATA, HENRY S.; AYALA-ARENAS, JORGE S.. Preparation and study of the main dosimetric properties by TL of sintered lithium silicate pellets. Journal of Luminescence, v. 255, p. 1-7, 2023. DOI: 10.1016/j.jlumin.2022.119580

    Abstract: This work presents the structural characteristics and the dosimetric properties under ionizing radiation of the lithium silicate (LSO) (LSO) phosphor. The structure of the synthesized material was determined by X-ray diffraction (XRD) method and Rietveld refinement method. The dosimetric properties of LSOLSO in the form of pellets were studied by thermoluminescence (TL) under the effect of different doses of γ-irradiation. The phosphor exhibited a TL emission curve with four TL peaks centered at 100, 182, 250 and 290 °C, with a light emission band centered at 385 nm. The TL dose-dependent γ-radiation dose response of the TL peak at 182 °C was linear in the low-dose region, from the order of mGy to 50 Gy. In addition, the phosphor exhibits lower fading, good reproducibility, and sensitivity of the order of commercial TLD-100 dosimeters.

    Palavras-Chave: lithium silicates; thermoluminescence; synthesis; dosimetry

  • IPEN-DOC 29611

    CASTANHEIRA, BRUNA; BROCHSZTAIN, SERGIO; OTUBO, LARISSA ; TEIXEIRA, ANTONIO C.S.C.. Periodic mesoporous organosilicas containing naphthalenediimides as organic sensitizers for sulfadiazine photodegradation. Journal of Hazardous Materials, v. 443, n. Part B, p. 1-9, 2023. DOI: 10.1016/j.jhazmat.2022.130224

    Abstract: In this work, periodic mesoporous organosilicas (PMO) functionalized with the organic sentisizer naphthalenediimide (NDI) were employed as heterogeneous catalysts for the photodegradation of the antibiotic sulfadiazine (SDZ), taken as a model for contaminants of emerging concern (CECs). The catalysts, designated as PMONDI, were prepared by surfactant-directed co-condensation of the precursor N,N′-bis(3-triethoxysilylpropyl)− 1,4,5,8-naphthalenediimide with tetraethoxysilane. The synthesized PMONDI were characterized using transmission electron microscopy, nitrogen adsorption isotherms and small and large angle x-ray scattering. The performance of PMONDI catalysts in the photodegradation of SDZ was compared to that of TiO2 nanoparticles impregnated into SBA-15 mesoporous silica (TiO2/SBA-15), under irradiation with a Hg lamp with a bandpass filter of 320–500 nm. Under optimal conditions, PMONDI degraded 100% of the SDZ in 45 min, while the total degradation of SDZ was achieved only after 150 min with TiO2/SBA-15. PMONDI also performed better than TiO2/SBA-15 in reuse tests. The mechanism of photodegradation with PMONDI involves the formation of excited triplet states of NDI (3NDI*) upon irradiation, which can then react with molecular oxygen to form reactive oxygen species, which degrade SDZ. Analysis of the SDZ degradation products indicated two main pathways: (1) hydroxylation of the aniline ring and (2) SO2 extrusion and rearrangement, followed by oxidation of the aniline ring to nitrobenzene. In conclusion, the great potential of the PMONDI materials as photocatalysts for CECs degradation was demonstrated in this work, encouraging further research on these materials for the degradation of pollutants.

    Palavras-Chave: sulfonamides; pyrimidines; photocatalysis; naphthalene

  • IPEN-DOC 29610

    MOREIRA, RENAN P. ; FRANCISCO, LEONARDO H.C. ; COSTA, ISRAEL F.; BARBOSA, HELLIOMAR P.; TEOTONIO, ERCULES E.S.; FELINTO, MARIA C.F.C. ; MALTA, OSCAR L.; BRITO, HERMI F.. Luminescence properties of BaMO4:Eu3+ (M: Mo or W) phosphors derived from co-precipitation reaction. Journal of Alloys and Compounds, v. 937, p. 1-11, 2023. DOI: 10.1016/j.jallcom.2022.168408

    Abstract: Luminescent BaMO4:xmol%Eu3+ materials (M: Mo or W, and x: 0, 2, 4, 6, 8, and 10 mol%) were successfully obtained by a coprecipitation method at room temperature without additional thermal treatment, leading to highly crystalline materials with reduced reaction times and low manufacturing cost. Structural analyses by powder X-ray diffraction and vibrational Raman techniques of the [WO4]2- and [MoO4]2- groups confirm a characteristic scheelite-type structure. The results indicate an average crystallite size at around 30 nm, and a highly pure phase has been supported by Rietveld refinement. SEM-EDS data of BaMO4:xmol%Eu3+ materials identified polycrystalline particles with bipyramidal-like morphology and homogeneous europium ion distribution. Additionally, the band gap energy (Eg) of barium molybdate and tungstate materials were calculated from reflectance data by the single-constant Kubelka-Munk function. Furthermore, the emission intensity, lifetime, and intrinsic emission quantum yield (Q Eu3+/Eu3+) of the materials have been determined and discussed. The luminescent properties of these materials are significantly influenced by the LMCT excitation bands (O2- → Mo6+, W6+, and Eu3+) as well as their intense red emission bands assigned to Eu3+ transitions. The experimental intensity parameter values Ω2 and Ω4 were evaluated from the emission spectra, using the magnetic dipole 5D0 → 7F1 transition as the standard reference. It was observed that the Ω2 values are much higher than the Ω4 values. This result is related to the fact that the 5D0 → 7F2 transition presents a much higher intensity than 5D0 → 7F1 one suggesting a low local symmetry around the Eu3+ ion, which might be due to angular distortions in the local coordination geometry. The high Q Eu3+/Eu3+ values (60–79%) indicated an overall high emission intensity for the prepared phosphors. These are special photonic features of the Eu3+-doped molybdate and tungstate, suggesting they could be suitable for luminescent materials applications.

    Palavras-Chave: luminescence; europium; tungstates; molybdates; coprecipitation; phosphors

  • IPEN-DOC 29609

    PANESI, A.R.Q. ; SILVA, R.P. ; SANTIAGO, E.I. . Numerical validation of direct ethanol fuel cell operating at high temperature. Ionics, v. 29, n. 3, p. 1039-1052, 2023. DOI: 10.1007/s11581-022-04852-5

    Abstract: In the present work, a three-dimensional steady-state model was developed to analyze the performance of high-temperature direct ethanol fuel cell (HT-DEFC) based on polybenzimidazole (PBI) electrolytes. A non-isothermal model of a HT-DEFC setup using a PBI/H3PO4 membrane was employed using computational fluid dynamics (CFD). This work is aiming at a validation of experimental data of HT-DEFC prototypes based on the simulation of polarization curves. The model predicts the mole concentration of H3PO4, heat and current density distributions, as well as mass fraction ethanol during operation at 180 °C. The heat transfer model was coupled to the electrochemical and mass transport, allowing that a particular heating configuration was investigated considering the temperature distribution on the PBI membrane. We have found that temperature and relative humidity (RH) are mostly related to PBI properties resulting from H3PO4 lixiviation and conductivity decreasing as well as ethanol crossover strongly interferes on the oxygen reduction reaction (ORR) rate, leading to poor HT-DEFC performance.

    Palavras-Chave: phosphoric acid; ethanol; direct ethanol fuel cells; temperature dependence; benzimidazoles; computer calculations; fluid mechanics

  • IPEN-DOC 29608

    GENESI, BIANCA P.; BARBOSA, RAQUEL de M.; SEVERINO, PATRICIA; RODAS, ANDREA C.D.; YOSHIDA, CRISTIANA M.P.; MATHOR, MONICA B. ; LOPES, PATRICIA S.; VISERAS, CESAR; SOUTO, ELIANA B.; SILVA, CLASSIUS F. da. Aloe vera and copaiba oleoresin-loaded chitosan films for wound dressings: microbial permeation, cytotoxicity, and in vivo proof of concept. International Journal of Pharmaceutics, v. 634, p. 1-12, 2023. DOI: 10.1016/j.ijpharm.2023.122648

    Abstract: Chitosan films are commonly used for wound dressing, provided that this polymer has healing, mucoadhesiveness and antimicrobial properties. These properties can be further reinforced by the combination of chitosan with polysaccharides and glycoproteins present in aloe vera, together with copaiba oleoresin’s pharmacological activity attributed to sesquiterpenes. In this work, we developed chitosan films containing either aloe vera, copaiba oil or both, by casting technique, and evaluated their microbial permeation, antimicrobial activity, cytotoxicity, and in vivo healing potential in female adult rats. None of the developed chitosan films promoted microbial permeation, while the cytotoxicity in Balb/c 3 T3 clone A31 cell line revealed no toxicity of films produced with 2 % of chitosan and up to 1 % of aloe vera and copaiba oleoresin. Films obtained with either 0.5 % chitosan or 0.5 % copaiba oleoresin induced cell proliferation which anticipate their potential for closure of wound and for the healing process. The in vivo results confirmed that tested films (0.5 % copaiba-loaded chitosan film and 0.5 % aloe vera-loaded chitosan film) were superior to a commercial dressing film. For all tested groups, a fully formed epithelium was seen, while neoformation of vessels seemed to be greater in formulations-treated groups than those treated with the control. Our work confirms the added value of combining chitosan with aloe vera and copaiba oil in the healing process of wounds.

    Palavras-Chave: medicinal plants; trees; polysaccharides; glycoproteins; wounds; healing

  • IPEN-DOC 29607

    MARTINS, LUCIANE; LESSA, LUIS G.F.; ALI, TACCYANNA M.; LAZAR, MONIZE; KIM, CHONG A.; KANTOVITZ, KAMILA R.; SANTAMARIA, MAURO P.; ARAUJO, CASSIA F.; RAMOS, CAROLINA J.; FOSTER, BRIAN L.; FRANCO, JOSE F.S. ; BERTOLA, DEBORA; NOCITI JUNIOR, FRANCISCO H.. Childhood hypophosphatasia associated with a novel biallelic ALPL variant at the TNSALP dimer interface. International Journal of Molecular Sciences, v. 24, n. 1, p. 1-10, 2023. DOI: 10.3390/ijms24010282

    Abstract: The goal of this study was to perform a clinical and molecular investigation in an eight-year-old female child diagnosed with hypophosphatasia (HPP). The proband and her family were evaluated by medical and dental histories, biochemical analyses, radiographic imaging, and genetic analysis of the tissue-nonspecific alkaline phosphatase (ALPL) gene. A bioinformatic analysis was performed to predict the structural and functional impact of the point mutations in the tissue-nonspecific alkaline phosphatase (TNSALP) molecule and to define their potential contribution to the phenotype. We identified a novel combination of heterozygous ALPL missense variants in the proband, p.Ala33Val and p.Asn47His, compatible with an autosomal recessive mode of inheritance and resulting in skeletal and dental phenotypes. Computational modeling showed that the affected Asn47 residue is located in the coil structure close to the N-terminal α-helix, whereas the affected Ala33 residue is localized in the N-terminal α-helix. Both affected residues are located close to the homodimer interface, suggesting they may impair TNSALP dimer formation and stability. Clinical and biochemical follow-up revealed improvements after six years of ERT. Reporting this novel combination of ALPL variants in childhood HPP provides new insights into genotype–phenotype associations for HPP and specific sites within the TNSALP molecule potentially related to a childhood-onset HPP and skeletal and dental manifestations. Beneficial effects of ERT are implicated in skeletal and dental tissues.

    Palavras-Chave: genotype; phenotype; alkaline phosphatase; hereditary diseases; dentistry; teeth; children; 3d printing

  • IPEN-DOC 29606

    CAMANI, PAULO H.; MIDHUN DOMINIC, C.D.; PARRA, DUCLERC F. ; MALTEZ, HELOISA F.; ROSA, DERVAL S.. Divalent metal ion removal from simulated water using sustainable starch aerogels: effect of crosslinking agent concentration and sorption conditions. International Journal of Biological Macromolecules, v. 226, p. 628-645, 2023. DOI: 10.1016/j.ijbiomac.2022.11.308

    Abstract: This paper evaluates corn starch aerogels, studying different crosslinking agent (trisodium citrate) concentrations (1:1, 1:1.5, and 1:2) and sorption conditions (contact time, adsorbent weight, and initial concentration) regarding the potentially toxic elements (PTEs) [Cd(II) or Zn(II)] adsorption of the aqueous systems. Besides, other properties of aerogels, such as structural properties, specific surface area, and mechanical performance, were evaluated. For adsorption results, better values were observed in adsorption capacity and efficiency for the initial concentration of 100 ppm. In addition, an adsorption time of 12 h and an adsorbent weight of 3.0 g obtained better results due to the possible balance in this time and the high specific surface area available for Cd(II) adsorption. As for the type of adsorbent, the Aero 1:1.5 sample (intermediate crosslinking agent concentration) obtained better results, possibly due to the high porosity, smaller pore sizes, high pore density, and high specific surface area (198 m2·g−1). In addition, hydroxyl groups in the starch aerogel removed Cd(II) ions with 30 % adsorption efficiency. Lastly, Aero 1:1.5 obtained a high mechanical strength at compression and a satisfactory compressive modulus. In contrast, starch aerogels did not absorb the Zn(II) ion.

    Palavras-Chave: maize; starch; gels; adsorption; elements; toxic materials

  • IPEN-DOC 29605

    MAIA, VICTORIA A. ; SANTOS, CAMILA M.G. ; AZEREDO, NATHALIA F.B. ; ZAMBIAZI, PRISCILLA J. ; ANTOLINI, ERMETE; NETO, ALMIR O. ; SOUZA, RODRIGO F.B. de . Conversion of nitrogen to ammonia using a Cu/C electrocatalyst in a polymeric electrolyte reactor. Electrochemistry Communications, v. 146, p. 1-4, 2023. DOI: 10.1016/j.elecom.2022.107421

    Abstract: The electrochemical conversion of N2 to NH3 using a polymeric electrolyte reactor is a promising method to accelerate the green production of hydrogen carriers. On this basis, we report the efficiency of ammonia production by the nitrogen reduction reaction using a Cu/C catalyst in a polymeric electrolyte membrane reactor. The Cu/C catalyst was prepared by the NaBH4 reduction method and characterized by X-ray diffraction, transmission electron microscopy, cyclic voltammetry, and conversion experiments performed in a polymer electrolyte membrane fuel cell type reactor. The X-ray diffraction results showed the presence of CuO2 and carbon phases, while the TEM images showed a high agglomeration of copper nanoparticles on carbon. The onset potential of nitrogen reduction was near to the Cu (I) to Cu0 reduction peak. Mass spectroscopy was used to observe the production of N2H2 and NH3 and the consumption of N2. Maximum ammonia production was detected at 0.0 V with a NH3 yield rate of 38.4 µg h−1 cm−2 and a faradaic efficiency of 42.57 %.

    Palavras-Chave: nitrogen; reduction; ammonia; electrolytic cells; nuclear fuels; fuel cells; copper; carbon; catalysts

  • IPEN-DOC 29604

    GUIMARAES, VITORIA P.; NANDENHA, JULIO ; ORZARI, LUIZ O.; FATIBELLO-FILHO, ORLANDO; OLIVEIRA NETO, ALMIR ; JANEGITZ, BRUNO C.; VICENTINI, FERNANDO C.; ASSUMPCAO, MONICA H.M.T.. Effect of TiO2 and synthesis strategies on formate oxidation: electrochemical and fuel cell approaches. Electrocatalysis, v. 14, n. 2, p. 221-231, 2023. DOI: 10.1007/s12678-022-00789-5

    Abstract: Direct formate fuel cells have gained increasing attention since formate can be obtained by CO2 reduction, being shown as a renewable power source. This paper reports the use of Pd nanoparticles supported on physical mixtures of Vulcan carbon and TiO2 in different ratios and different Pd reduction methodologies. The materials were prepared using sodium borohydride as a reducing agent and analyzed toward formate oxidation in alkaline media. The prepared electrocatalysts showed peaks of Pd face-centered cubic and TiO2 anatase and rutile phases and an average particle size between 3.7 and 7.9 nm. Experiments considering formate electro-oxidation (voltammetry and chronoamperometry) showed that the presence of TiO2 is favorably using both synthesis methodologies while single cells revealed Pd nanoparticles supported on physical mixtures of carbon and TiO2, in the proportion of 75:25 as the most efficient, which was explained by the carbon high electrical conductivity and small quantities of TiO2 working as co-catalyst.

    Palavras-Chave: palladium; nanoparticles; titanium oxides; oxidation; formate fuel cells

  • IPEN-DOC 29603

    FONSECA, E.B.; FATICHI, A.Z.; TERADA, M.; BUGARIN, A.F.S. ; RODRIGUEZ, J.; COSTA, ISOLDA ; RAMIREZ, A.J.. Quantitative analysis of susceptibility to intergranular corrosion in alloy 625 joined by friction stir welding. Corrosion Engineering, Science and Technology, v. 58, n. 2, p. 138-144, 2023. DOI: 10.1080/1478422X.2022.2152174

    Abstract: Alloy 625 is a Ni-based alloy used in aerospace, energy, chemical, oil and gas industries, mainly as cladding material due to its corrosion resistance, high strength and creep resistance at high temperature. In this study, microstructural evaluation and susceptibility to intergranular corrosion of base metal and friction stir welded Alloy 625 were investigated. Friction stir welded joints exhibited a lower corrosion rate and degree of sensitisation compared to the base metal. It is mainly due to grain refinement and lower cooling rate of the friction stir welding process. The stir zone of the present weld has a finer grain structure and lower density of twin boundaries than the base metal and it led to the improvement of the mechanical and corrosion properties.

    Palavras-Chave: inconel 625; nickel base alloys; intergranular corrosion; friction welding; microstructure; microhardness

  • IPEN-DOC 29602

    LOPES, ISABELA S.; CASSAS, FERNANDO; VEIGA, THIAGO A.M.; SILVA, FLAVIA R. de O. ; COURROL, LILIA C.. Synthesis and characterization of Eugenia uniflora L. silver nanoparticles and L-cysteine sensor application. Chemistry and Biodiversity, v. 20, n. 1, p. 1-12, 2023. DOI: 10.1002/cbdv.202200787

    Abstract: L-Cysteine (Cys) is a non-essential sulfur-containing amino acid, crucial for protein synthesis, detoxification, and several metabolic functions. Cys is widely used in the agricultural, food, cosmetic, and pharmaceutical industries. So, a suitable sensitive and selective sensing approach is of great interest, and a low-cost sensor would be necessary. This article presents silver nanoparticles (EuAgNPs) synthesized by a green synthesis method using Eugenia uniflora L. extracts and photoreduction. The nanoparticles were characterized by UV/VIS, transmission electron microscopy, high-performance liquid chromatography (HPLC), FTIR, and Zeta potential. With the addition of Cys in the EuAgNPs solution, the terminal thiol part of L-cysteine binds on the surface of nanoparticles through Ag−S bond. The EuAgNPs and CysAgNPs coexist until flavonoids bound the amino group of Cys, enhancing the red color of solutions. The EuAgNPs provided selectivity to detect Cys among other amino acids, and its detection limit was found to be 3.8 nM. The sensor has the advantages of low-cost synthesis, fast response, high selectivity, and sensitivity.

    Palavras-Chave: trees; cysteine; amino acids; silver; nanoparticles; photochemistry; reduction

  • IPEN-DOC 29601

    LIMA, ELIANA R. ; FREIRE, RENAN P. ; SUZUKI, MIRIAM F. ; OLIVEIRA, JOAO E. ; YOSIDAKI, VANESSA L. ; PERONI, CIBELE N. ; SEVILHANO, THAIS ; ZORZETO, MOISES; TORATI, LUCAS S.; SOARES, CARLOS R.J. ; LIMA, IGOR D. de M.; KRONENBERGER, THALES; MALTAROLLO, VINICIUS G.; BARTOLINI, PAOLO . Isolation and characterization of the Arapaima gigas growth hormone (ag-GH) cDNA and three-dimensional modeling of this hormone in comparison with the human hormone (hGH). Biomolecules, v. 13, n. 1, p. 1-17, 2023. DOI: 10.3390/biom13010158

    Abstract: In a previous work, the common gonadotrophic hormone α-subunit (ag-GTHα), the ag-FSH β- and ag-LH β-subunit cDNAs, were isolated and characterized by our research group from A. gigas pituitaries, while a preliminary synthesis of ag-FSH was also carried out in human embryonic kidney 293 (HEK293) cells. In the present work, the cDNA sequence encoding the ag-growth hormone (ag-GH) has also been isolated from the same giant Arapaimidae Amazonian fish. The ag-GH consists of 208 amino acids with a putative 23 amino acid signal peptide and a 185 amino acid mature peptide. The highest identity, based on the amino acid sequences, was found with the Elopiformes (82.0%), followed by Anguilliformes (79.7%) and Acipenseriformes (74.5%). The identity with the corresponding human GH (hGH) amino acid sequence is remarkable (44.8%), and the two disulfide bonds present in both sequences were perfectly conserved. Three-dimensional (3D) models of ag-GH, in comparison with hGH, were generated using the threading modeling method followed by molecular dynamics. Our simulations suggest that the two proteins have similar structural properties without major conformational changes under the simulated conditions, even though they are separated from each other by a >100 Myr evolutionary period (1 Myr = 1 million years). The sequence found will be used for the biotechnological synthesis of ag-GH while the ag-GH cDNA obtained will be utilized for preliminary Gene Therapy studies.

    Palavras-Chave: fishes; pituitary hormones; gonadotropins; molecules; cloning; dna sequencing

  • IPEN-DOC 29600

    FREIRE, RENAN P. ; HERNANDEZ-GONZALEZ, JORGE E.; LIMA, ELIANA R. ; SUZUKI, MIRIAM F. ; OLIVEIRA, JOAO E. de ; TORATI, LUCAS S.; BARTOLINI, PAOLO ; SOARES, CARLOS R.J. . Molecular cloning and AlphaFold modeling of thyrotropin (ag-TSH) from the Amazonian fish Pirarucu (Arapaima gigas). Bioinformatics and Biology Insights, v. 17, p. 1-13, 2023. DOI: 10.1177/11779322231154148

    Abstract: Arapaima gigas, known as Pirarucu in Brazil, is one of the largest freshwater fish in the world. Some individuals could reach 3 m in length and weight up to 200 kg. Due to extinction risks and its economic value, the species has been a focus for preservation and reproduction studies. Thyrotropin (TSH) is a glycoprotein hormone formed by 2 subunits α and β whose main activity is related to the synthesis of thyroid hormones (THs)—T3 and T4. In this work, we present a combination of bioinformatics tools to identify Arapaima gigas βTSH (ag-βTSH), modeling its molecular structure and express the recombinant heterodimer form in mammalian cells. Using the combination of computational biology, based on genome-related information, in silico molecular cloning and modeling led to confirm results of the ag-βTSH sequence by reverse transcriptase-polymerase chain reaction (RT-PCR) and transient expression in human embryonic kidney (HEK293F) cells. Molecular cloning of ag-βTSH retrieved 146 amino acids with a signal peptide of 21 amino acid residues and 6 disulfide bonds. The sequence has a similarity to 39 fish species, ranging between 43.1% and 81.6%, whose domains are extremely conserved, such as cystine knot motif and N-glycosylation site. The Arapaima gigas thyrotropin (ag-TSH) model, solved by AlphaFold, was used in molecular dynamics simulations with Scleropages formosus receptor, providing similar values of free energy ΔGbind and ΔGPMF in comparison with Homo sapiens model. The recombinant expression in HEK293F cells reached a yield of 25 mg/L, characterized via chromatographic and physical-chemical techniques. This work shows that other Arapaima gigas proteins could be studied in a similar way, using the combination of these techniques, recovering more information from its genome and improving the reproduction and preservation of this prehistoric fish.

    Palavras-Chave: fishes; thyroid hormones; tsh; molecules; cloning; toxicity

  • IPEN-DOC 29599

    NEGAHDARY, MASOUD; HIRATA, MARIO H.; SAKATA, SOLANGE K. ; CICONELLI, ROZANA M.; BASTOS, GISELE M.; BORGES, JESSICA B.; THUROW, HELENA S.; SILVEIRA JUNIOR, ALCEU T.; SAMPAIO, MARCELO F.; GUIMARAES, LARISSA B.; MAEDA, BRUNO S.; ANGNES, LUCIO. Sandwich-like electrochemical aptasensing of heat shock protein 70 kDa (HSP70): application in diagnosis/prognosis of coronavirus disease 2019 (COVID-19). Analytica Chimica Acta, v. 1242, p. 1-10, 2023. DOI: 10.1016/j.aca.2022.340716

    Abstract: In this research, by using aptamer-conjugated gold nanoparticles (aptamer-AuNPs) and a modified glassy carbon electrode (GCE) with reduced graphene oxide (rGO) and Acropora-like gold (ALG) nanostructure, a sandwich-like system provided for sensitive detection of heat shock protein 70 kDa (HSP70), which applied as a functional biomarker in diagnosis/prognosis of COVID-19. Initially, the surface of the GCE was improved with rGO and ALG nanostructures, respectively. Then, an aptamer sequence as the first part of the bioreceptor was covalently bound on the surface of the GCE/rGO/ALG nanostructures. After adding the analyte, the second part of the bioreceptor (aptamer-AuNPs) was immobilized on the electrode surface to improve the diagnostic performance. The designed aptasensor detected HSP70 in a wide linear range, from 5 pg mL−1 to 75 ng mL−1, with a limit of detection (LOD) of ∼2 pg mL−1. The aptasensor was stable for 3 weeks and applicable in detecting 40 real plasma samples of COVID-19 patients. The diagnostic sensitivity and specificity were 90% and 85%, respectively, compared with the reverse transcription-polymerase chain reaction (RT-PCR) method.

    Palavras-Chave: gold; nanomaterials; coronaviruses; electrochemistry; electrodes; graphene

  • IPEN-DOC 29598

    AZEVEDO, JULIANA S.; BRAGA, ELISABETE S.; KUNIYOSHI, LEONARDO S.; FAVARO, DEBORAH I.T. . Seasonal arsenic in catfish (Siluriformes, Ariidae) and the hydrochemical conditions of two areas in a Ramsar site on the Brazilian coast. Anais da Academia Brasileira de Ciências, v. 95, n. 2, p. 1-11, 2023. DOI: 10.1590/0001-3765202320210033

    Abstract: The construction of a data bank concerning metal and metalloid content of bioindicator fish from coastal areas is very important as it can help environmental managers in decision making. In natural conditions, the concentration of elements can be influenced by abiotic parameters such as water salinity. In this study, catfish Cathorops spixii were evaluated concerning the total arsenic (As) concentration in the muscle tissues of individuals subjected to different abiotic conditions in the Cananéia-Iguape Estuarine-Lagoon Complex (CIELC), which was recently included on the Ramsar list of wetlands of international importance. Seventy-four catfish were seasonally caught in the northern and southern regions of the CIELC and their hydrochemical parameters were obtained. C. spixii from the southern, best preserved, area showed arsenic concentrations around ten times higher than the maximum limit established for fish intended for human consumption. However, these high concentrations of arsenic could be associated with the abiotic parameters of the water, such as salinity variations, in this area.

    Palavras-Chave: fishes; arsenic; estuaries; environmental protection; salinity

  • IPEN-DOC 29597

    CARVALHO, SABRINA G.M. ; MUCCILLO, ELIANA N.S. ; MUCCILLO, REGINALDO . Design and validation of an experimental setup for evaluation of gas permeation in ceramic membranes. Membranes, v. 13, n. 2, p. 1-12, 2023. DOI: 10.3390/membranes13020246

    Abstract: An experimental setup for the evaluation of permeation of gaseous species with the possibility of simultaneously collecting electrochemical impedance spectroscopy data in disk-shaped ceramic membranes was designed and assembled. It consists of an alumina sample holder with thermocouple tips and platinum electrodes located close to both sides of the sample. Water-cooled inlet and outlet gas connections allowed for the insertion of the sample chamber into a programmable split tubular furnace. Gas permeation through a ceramic membrane can be monitored with mass flow controllers, a mass spectrometer, and an electrochemical impedance analyzer. For testing and data validation, ceramic composite membranes were prepared with the infiltration of molten eutectic compositions of alkali salts (lithium, sodium, and potassium carbonates) into porous gadolinia-doped ceria. Values of the alkali salt melting points and the permeation rates of carbon dioxide, in agreement with reported data, were successfully collected.

    Palavras-Chave: ceramics; membranes; carbon dioxide; permeability

  • IPEN-DOC 29558

    NETO, A.B.C. . Risks to be considered in nuclear reactor decommissioning projects in Brazil. Brazilian Journal of Radiation Sciences, v. 10, n. 4, p. 1-24, 2022. DOI: 10.15392/2319-0612.2022.2111

    Abstract: In recent years, Brazil has intensified investments in nuclear innovation for peaceful purposes. Currently, in the country, there are six reactors in operation and three under construction. These reactors, at the end of their useful life, must be decommissioned, in a process that includes technical and administrative actions aimed at the partial or total removal of regulatory control, with a view of to the safety of the installation site, the health of employees, the public, and the protection of the environment. Thus, these activities involve risks that must be managed systematically, following the rules and guidelines established by responsible bodies. The International Atomic Energy Agency (IAEA) recently identified the need for practical guidelines for risk management in decommissioning projects and elaborated the publication “Management of Project Risks in Decommissioning” of the Safety Reports Series Nº 97. In Brazil, there is no experience in execution the decommissioning of nuclear reactors, thus, this work will present and analyze the main risks of nuclear reactor decommissioning projects in Brazil, using techniques from the risk assessment process of the ISO/IEC 31010 Standard, considering the wide international experience portrayed on the subject.

  • IPEN-DOC 29557

    ARAUJO, M.M. ; REIS, F.C. ; ROMANO, J.I.S. ; ARTHUR, V.. Effects of gamma radiation on adults of Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) and Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) collected in the retail trade in São Paulo/SP city. Brazilian Journal of Radiation Sciences, v. 10, n. 4, p. 1-12, 2022. DOI: 10.15392/2319-0612.2022.2086

    Abstract: Brazil is one of the world's largest grain producers, and inadequate storage favors the appearance of pests. Among the most important insect species, the genus Sitophilus and Tribolium stand out. The constant use of chemical pesticides leads to the selection of resistant populations and the need to study different methods for integrated control. Considering these aspects, the present study aimed to evaluate the mortality of adult individuals of S. zeamais in brown rice and T. castaneum in wheat flour, collected on substrates sold in the retail trade in São Paulo/SP city, exposed to increasing doses of gamma radiation. The experiment was carried out at the Radiation Technology Center at the Institute for Energetic and Nuclear Research – IPEN/USP, the substrates with the specimens were irradiated with doses of 0 (control), 25, 50, 75, 100, and 200 Gy in a Cobalt-60 source, type Gammacell 220, at a dose rate of 0.903 kGy/hour. The experiment consisted of 4 replicates per treatment and each replicate 10 insects, in a total of 40 insects per treatment, and the statistical design was completely randomized. The dose of 75 Gy was sufficient to obtain 100% efficiency for S. zeamais, but the dose of 200 Gy did not reach satisfactory efficiency for controlling T. castaneum. Therefore, a dose of 400 Gy should be recommended for the control of these two insect species in their respective substrates.

  • IPEN-DOC 29556

    FONTOLAN, A.F.A.M. ; SOUZA, C.D. de . Assessment of public perception of radioactivity in Brazil. Brazilian Journal of Radiation Sciences, v. 10, n. 4, p. 1-19, 2022. DOI: 10.15392/2319-0612.2022.2095

    Abstract: Nuclear energy divides public opinion with its “good” and “bad” applications. Almost immediately after the discovery of radiation, radioactive elements purified by the Curies were used in health treatments, but with the nuclear bombs of Hiroshima and Nagasaki, the subject was marked by bad public opinion, being related to death and destruction. Nowadays, nuclear physics is used in many important fields, such nuclear medicine for the diagnosis and treatment of various types of diseases, but the prejudice and lack of knowledge of the general public has not yet improved its “fame”. This work proposes to change a little of this paradigm. Through a questionnaire, the public perception of radioactivity was evaluated. The most important result obtained is that the public is interested in learning about radiation and nuclear energy and is willing to change their negative views.

  • IPEN-DOC 29555

    BORSOI, S.S.; BARONI, D.B.; MATTAR NETO, M. ; OLIVEIRA, P.S.P. ; MATURANA, M.C.. Risk-based design of electric power systems for non-conventional nuclear facilities at shutdown modes. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-17, 2022. DOI: 10.15392/2319-0612.2022.2063

    Abstract: The work presents a methodology for assessing the safety of electrical system designs for non-conventional nuclear facilities in shutdown. The methodology adopts the core damage frequency as the main risk measure to assess the different architectures of power systems in a non-conventional nuclear facility. Among the reasons is the absence of a specific regulatory basis for this type of installation. The adoption of standards for nuclear power plants by non-conventional nuclear facilities does not take into account the functional and operational particularities of these installations, imposing criteria that are often overestimated, which can even lead to an increase in the financial risk for carrying out the projects. Safety probabilistic analyzes become essential tools for the facilities design and licensing. The modeling and quantification of systems failures in charge of ensuring the nuclear safety of non-conventional nuclear facilities are carried out in the CAFTA software environment. In these studies, the analysis of electrical system configurations and their influence on the overall risk of the installation stand out.

  • IPEN-DOC 29554

    FERRARI, L.A. ; AYOUB, J.M.S. ; TAVARES, R.L.A.; SILVA, A.L.C.; SENEDA, J.A. . Must nuclear energy be increased on Brazilian energy mix in a Post-COVID-19 world?. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-20, 2022. DOI: 10.15392/2319-0612.2022.1920

    Abstract: This paper aims to discuss the convenience and feasibility of increasing the nuclear energy participation on the Brazilian energy mix, amid a national context of climate change, scarcity of natural resources necessary to baseload energy generation, particularly hydropower, discussions on a possible restart and expansion of Brazilian nuclear program, whilst the population still suffers socioeconomic impacts resulting from COVID-19 pandemic as well as the pre-pandemic economic crisis. The work proposes four analysis axes: environmental factors, economic, safety/legislation and technological aspects, and through bibliographic research in scientific articles published in journals, theses, dissertations, laws, regulations and international recommendations, it was possible, as a result of the research, to draw an optimistic overview of a possible future expansion of the Brazilian nuclear program, considering the advantages and challenges of using the nuclear alternative when compared to other energy sources.

  • IPEN-DOC 29553

    CELESTINO, P.A.P. ; SORDI, G.M.A.A. . Study of radiation protection vestments for maintenance of mobile nuclear power plants. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-16, 2022. DOI: 10.15392/2319-0612.2022.1867

    Abstract: Most radiation exposure to personnel comes from inspection, maintenance, and repair within the reactor compartment. The objective of this paper was to discover the garment that, at the same time, presents the best result for the attenuation of ionizing radiation, as well as good ergonomics for the maintenance professional of mobile nuclear plants. For this, market research was carried out and, as a result, nine Radiation Protection Vestments (VPRs) were found, from five different manufacturers and from three countries, the United States, Japan and China; and which are feasible to be acquired. To choose the VPR, the optimization techniques of CIPR 55 were used: Multi-Attribute Utility Analysis and Multi-Criteria Outranking Analysis. Based on the information provided by the manufacturers, five attributes were chosen for comparison: protection cost, percentage of ionizing radiation attenuation, weight, discomfort, and surface decontamination of the vestment. To verify the robustness of the analytical solution, the values of the scaling constants were re-calculated, where it was observed that the analytical solution found is strongly influenced when the protection cost is changed, as it is the highest cost VPR among all those surveyed. The VPR chosen by both optimization techniques was the STEMRAD 360, which has the highest attenuation of ionizing radiation, as well as being the VPR with greater emphasis on ergonomics.

  • IPEN-DOC 29552

    SILVA, T.P.; MATURANA, M.C.; OLIVEIRA, P.S.P. de ; MATTAR NETO, M. . External Events PSA: requirements applicable to new nuclear installations projects after Fukushima Daiichi accident. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-8, 2022. DOI: 10.15392/2319-0612.2022.1977

    Abstract: Since the Fukushima Daiichi accident, external events analysis has become a priority issue within regulatory bodies, operators, and designers, raising concerns about the capabilities of nuclear power plants to withstand severe conditions. Generally, the methodology applied to the Probabilistic Safety Assessment (PSA) of external events consists of the identification of potential single and combined external hazards, screening of external hazards, analysis of site and plant response, analysis of initiating events and quantification of accident sequences probabilities. Therefore, in this paper, the requirements and other information on new nuclear installations projects necessary to implement a comprehensive PSA of external events throughout plant lifetime are evaluated. In addition, it is necessary to clearly identify all the resources that must be available to continuously expand PSA scope to include all types of initiating events, levels of analysis and plant operation modes.

  • IPEN-DOC 29551

    FALOPPA, A.A. ; FAINER, G. ; FIGUEIREDO, C.D.R. ; CARVALHO, D.S.M. ; MATTAR NETO, M. . IEA-R1 renewed primary system pump B1-B nozzles stress analysis. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-14, 2022. DOI: 10.15392/2319-0612.2022.1892

    Abstract: The present report is a summary of the structural analysis of the pump nozzles applying the finite element method by using the Ansys computer program. The IEA-R1 RR is an open pool-type moderated and cooled by light water using beryllium/graphite as a reflector. The reactor can reach up to 5MW of thermal power cooled by the primary and secondary systems. The primary coolant system consists of a piping arrangement, a decay tank, two pumps, and two heat exchangers. The primary pump B1-B presented some failures requiring refurbishment by a new one. The pump used in the IEA-R1 must meet the requirements inherent to the nuclear installation, in addition to the operational requirements for rotating equipment, such as flow and pressure, and structural integrity of the body and nozzles. The supplier specified the type of pump suitable for the System. The pump furnished granted mechanical allowable loads for the nozzles that were lower than the loads imposed by the piping on the nozzles. To enable the installation of the pump in the primary circuit, new support was inserted in the piping system next to the pump minimizing efforts and deformations. A piping stress analysis was carried out to obtain the new efforts imposed on the nozzles. For validation of the motor pump set, a verification of the nozzles was done compared with API 610 standard loads, and the allowable loads of the provider. Finally, a structural analysis of the pump nozzles with the new loads was developed using the finite element method. The calculated stresses meet the limits prescribed by the ASME code; therefore, the new B1-B Pump is approved for operation at the IEA-R1 Nuclear Research Reactor primary circuit.

  • IPEN-DOC 29521

    VICENTE, MARCOS A.A.H.; SILVA, LEONARDO G.A. ; LIMA, NELSON B. ; OLIVEIRA, RENE R. ; BERNUSSI, AYRTON; SARMENTO, BRUNO; BARBOSA, ISABELLA T.F.; MUNHOZ JUNIOR, ANTONIO H.. Synthesis of pseudoboehmite nanoparticles and use in simvastatin drug delivery. Defect and Diffusion Forum, v. 420, p. 141-151, 2022. DOI: 10.4028/p-04240m

    Abstract: Pseudoboehmite is an aluminium compound with a structure similar to that of boehmite. The unit cell of the pseudoboehmite is slightly larger than that of the boehmite because of the greater incorporation of water in the same structure [1]. It has particles of nanometric dimensions and can be synthesized with extremely high purity. Several papers published in the literature show the potential of using this material in the controlled release of drugs, including cancer treatment [2,3]. Using drugs in complexes incorporated into polymer matrices and ceramic gels can lead to adequate control of gastrointestinal absorption when administered orally. Consequently, there is the possibility of promoting a gradual action through the progressive release of the drug, thus increasing its efficiency and reducing dose and toxicity. Previous studies have shown that pseudoboehmite is non-toxic and can be used for drug delivery. During the tests to determine the toxicity of this material, it was observed that the blood glucose content was reduced in mice that took pseudoboehmite by gavage. Since pseudoboehmite is obtained via low-cost inorganic synthesis, different physicochemical characteristics can be incorporated into this high purity medium. The formed structure was evaluated as a drug delivery system to establish a profile of the influence of the physicochemical properties of a molecule in the process of interaction with pseudoboehmite, a drug with recognized pharmacological activity, simvastatin (IUPAC name (1S,3R,7S,8S,8aR)-8-{2-[(2R,4R)-4-hydroxy-6-oxooxan-2-yl]ethyl}-3,7-dimethyl-1,2,3,7,8,8a-hexahydronaphthalen-1-yl 2,2-dimethylbutanoate) was choose. It also emphasizes the importance of pseudoboehmite as a drug carrier, serving as a precursor to new therapeutic systems. The synthesis of pseudoboehmite from ammonium hydroxide and aluminium nitrate was optimized to release simvastatin in vitro. After absorption and hydrolysis in the liver to form the active β-hydroxy acid metabolite, simvastatin acts as a potent reversible, competitive inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, an early and rate-limiting enzyme in the biosynthesis of cholesterol.

  • IPEN-DOC 29520

    COUTO, CAMILA P. ; BAERT, KITTY; COSTA, ISOLDA ; PANOSSIAN, ZEHBOUR; DE GRAEVE, IRIS; TERRYN, HERMAN; ROSSI, JESUALDO L. ; REVILLA, REYNIER I.. The hot-stamping effect on the corrosion properties of the 22MnB5 steel coated with hot-dip aluminum-silicon assessed by a salt spray test and Raman spectroscopy. Corrosion, v. 78, n. 4, p. 339-349, 2022. DOI: 10.5006/4016

    Abstract: The effect of hot stamping on the corrosion properties of boron-manganese 22MnB5 steel coated with hot-dip aluminum-silicon was evaluated under severe conditions by a continuous salt spray test (SST). The corrosion mechanism changed from localized to generalized, as cathodic precipitates were not present after hot stamping. Intrinsic defects in press-hardened steel samples were the reason for severe damage in both metallic coating and steel substrate under SST conditions. The red rust formed at the top surface, characterized as different iron-based compounds, is due to both the iron diffusion from the steel substrate toward the surface and the corrosion of the steel substrate.

  • IPEN-DOC 29519

    GUSMAO, CAROLINA de A.; BORGES, LAURA T.; PALHARIM, PRISCILA H.; OTUBO, LARISSA ; RODRIGUES, ORLANDO ; GOUVEA, DOUGLAS; RAMOS, BRUNO; TEIXEIRA, ANTONIO C.S.C.. Synthesis, characterization, and application of Pt/PtO2-TiO2/SiO2 materials on a continuous flow packed bed microreactor for enhanced photocatalytic activity under sunlight. Water, v. 14, n. 23, p. 1-18, 2022. DOI: 10.3390/w14233864

    Abstract: The present work aimed at the development of Pt-TiO2/SiO2 materials applied to the degradation of a pharmaceutical pollutant in a fixed-bed microreactor in continuous mode. First, a wide investigation of the optimal platinum content in TiO2/SiO2 was carried out based on extensive characterization through XRD, DRS, SEM, TEM, and XPS techniques. For the content range studied, no significant changes were observed in the crystallinity of the material, with peaks related to the anatase phase and PtO2 in the diffractograms. SEM images combined with EDS spectra indicated the presence of platinum and a large heterogeneity in the particles. MET analyses showed PtO2 nanoparticles in close contact with TiO2, allowing the formation of a type II heterojunction. XPS showed platinum in the 0 and +4 oxidation states, suggesting that platinum metal and PtO2 are both present. Regarding the degradation experiments, the optimal catalyst achieved 81% degradation of acetaminophen for a residence time of 1 h, while the catalyst without platinum reached only 27% degradation. The catalyst activity dropped from 81 to 57% in 2 h and remained stable for six reuse cycles. Increasing the inlet flow rate and concentration reduced the pollutant degradation although there was an increase in the reaction rate. Finally, a photocatalytic mechanism was proposed in which a type II heterojunction was developed, with generation of hydroxyl radicals by the positive holes in the VB of TiO2 as well as superoxide radicals by the electrons in the CB of PtO2.

  • IPEN-DOC 29518

    TASSO, ORION G. ; ZAMBONI, CIBELE B. ; SILVA, ANA C.K. de S. ; MEDEIROS, JOSE A.G. de ; SILVA, DALTON G.N. da . Comparação de desempenho do espectrômetro portátil de fluorescência de raios-X utilizando alvos de Au e Ag para análise de amostras na área da saúde / Performance comparison of portable X-ray fluorescence spectrometer using Au and Ag targets for sample analysis in healthcare. Revista Remecs, v. 7, n. 13, p. 29-40, 2022. DOI: 10.24281/rremecs2022.7.13.29-40

    Abstract: Este trabalho teve por objetivo avaliar o desempenho do espectrômetro portátil e compacto de Fluorescência de Raios-X (pFRX), para dosagem de íons em amostras biológicas de interesse na área da saúde (prioritariamente fluidos corpóreos como soro e urina), utilizando alvos de Prata (Ag) e Ouro (Au). O foco das comparações foi direcionado às análises quantitativas de elementos de relevância clínica e nutricional (prioritariamente a dosagem de Ca, Cl, Fe, K, P e S). Para este estudo foram avaliados (para cada alvo) os parâmetros: linearidade, reprodutibilidade, acurácia, sensibilidade e limite de detecção. Essas investigações permitiram a realização de um estudo comparativo entre os alvos, com a finalidade de fornecer subsídios que permitem a escolha adequada do alvo (Ag e/ou Au), agilizando as medidas além de fornecer resultados mais precisos. Os resultados de FRX em soro e urina formam comparados com as dosagens obtidas pela técnica de Análise por Ativação com Nêutrons e apresentaram boa concordância.

  • IPEN-DOC 29517

    ARAUJO, MARCIO M. de ; SALAS, FERNANDO J.S.; ARTHUR, VALTER. Marcação de insetos para estudos biológicos / Insect marking for biological studies. Revista de la Facultad de Agronomía, v. 121, n. 1, p. 1-14, 2022. DOI: 10.24215/16699513e093

    Abstract: A técnica de marcação permite estudar os comportamentos e interações ecológicas dos insetos, como por exemplo padrões de dispersão, movimento, territorialidade, manuseio, consumo de alimentos, associações vetor-parasita, e cadeias ou teias alimentares. Essa revisão descreve as vantagens e desvantagens dos marcadores, destacando três métodos cujo diferencial é a permanência no inseto independente do estágio de vida. Os radioisótopos minimizam a manipulação direta e o trauma nos insetos, podem ser aplicados em grandes populações e são facilmente rastreáveis, porém o seu descarte limita a aplicação em campo. Os isótopos estáveis ocorrem naturalmente no ambiente, não são radioativos e estão relacionados à estudos ecológicos de níveis tróficos e processos metabólicos, dentre os elementos mais são utilizados, os isótopos de carbono refletem principalmente a dieta dos animais; os isótopos de nitrogênio refletem as práticas agrícolas (extensiva x intensiva) e em parte a dieta. Os isótopos de oxigênio e hidrogênio são vinculados à composição isotópica da água que, por sua vez, é dependente de fatores geográficos tais como altitude, clima e latitude. Por sua vez, os oligoelementos também são utilizados como marcadores internos (não radioativos) e podem variar de acordo com a localização geográfica alterando as quantidades encontradas nas plantas e insetos. Portanto, a busca de uma melhor metodologia que permita detectar a correlação dos insetos com o homem e o meio ambiente depende do tipo de estudo a ser realizado.

  • IPEN-DOC 29516

    AQUINO, SIMONE ; SILVA, FRANCISCO C. de M. e. Rare and opportunistic mycosis by Nigrospora spp. in a calf / Micose rara e oportunista por Nigrospora spp. em bezerra. Journal of Veterinary Science and Public Health, v. 9, n. 1, p. 122-132, 2022. DOI: 10.4025/revcivet.v9i1.56871

    Abstract: Os fungos estão presentes em diferentes ambientes, onde homens e animais estão expostos, como no solo, plantas e no ar. No entanto, fungos ambientais podem se tornar oportunistas e causar graves lesões de pele, oculares, pulmonares, micetomas, dentre outras, visto que as micoses oportunistas estão associadas às condições imunológicas do hospedeiro. O fungo do gênero Nigrospora é raramente considerado um patógeno oportunista ou agente primário de micoses. O objetivo deste relato de caso é descrever uma rara micose oportunista de pele, causada por Nigrospora em um bezerro de seis meses, fêmea, com escore de condição corporal ruim devido à desnutrição. Amostras de pele foram inoculadas em placas de Petri contendo ágar Sabouraud e após sete dias de incubação a 25(±2) ºC, lâminas de cultura examinadas em microscopia ótica com azul de lactofenol permitiram a identificação de estruturas conidiais de Nigrospora spp. Com a aplicação tópica semanal de solução a 1% de iodóforo, o animal apresentou a completa remissão dos sintomas após oito semanas.

  • IPEN-DOC 29515

    MAZER, AMANDA C. ; YORIYAZ, HELIO . Avaliação de registro de imagem realizado com e sem pontos de referência extraídos através da técnica SIFT / Image registration assessment performed with and without landmarks extracted using SIFT technique. Revista Brasileira de Física Médica, v. 16, p. 1-8, 2022. DOI: 10.29384/rbfm.2022.v16.19849001676

    Abstract: Em Radioterapia Guiada por Imagem (IGRT), é comum a aquisição de diversas imagens de um paciente e, por consequência, a realização de registro de imagem para a comparação entre elas. Devido a isso, é fundamental que sejam realizados tanto um bom registro quanto um bom controle da qualidade (CQ) do registro. O objetivo deste trabalho é avaliar um registro de imagem quando realizado com e sem pontos de referência. Para isso, imagens de Tomografia Computadorizada (TC) de um paciente da radioterapia foram utilizadas para realizar registros rígido e elástico, com e sem pontos de referência. A técnica Scale Invariant Feature Transform (SIFT) foi utilizada para desenvolver um algoritmo para a extração semiautomática de pontos-chave estáveis das imagens, tanto para os registros quanto para a avaliação de tais registros. Através dos valores de erro médio, erro máximo e Informação Mútua (IM) encontrados, foi possível verificar um melhor alinhamento das imagens quando realizado o registro partindo inicialmente dos pontos de referência extraídos, em comparação com o alinhamento realizado sem esses pontos de referência. A SIFT mostrou ser uma ótima ferramenta para realizar ambas as tarefas e, quando possível, o profissional da clínica deve realizar um bom CQ quantitativo de registro, considerando pontos de referência distribuídos pelas imagens.

  • IPEN-DOC 29514

    SILVA FILHO, JORGE C.; SILVA, SUELANNY C. da; VENANCIO, EVERALDO C.; TAKIISHI, HIDETOSHI ; ABE, IGOR Y.; SOARES, EDSON P. ; ANTUNES, RENATO A.; REY, JOSE F.Q.; MARTINEZ, LUIS G. ; ESCOTE, MARCIA T.. Aplicação de derivados de grafeno em baterias e ímãs permanentes / Application of graphene derivatives in batteries and permanent magnets. Revista da ABPN, v. 14, n. 41, p. 124-142, 2022. DOI: 10.31418/2177-2770.2022.v14.n41.p124-142

    Abstract: O presente trabalho aborda o estudo sobre a importância tecnológica dos compostos de grafeno, evidenciando a síntese, a caracterização do óxido de grafeno (GO) e óxido de grafeno reduzido (rGO) e suas aplicações em baterias e imãs permanentes de neodímio-ferro-boro. Os resultados de difração de raios-X mostraram a presença de apenas um pico em aproximadamente 2θ = 11°, o qual corresponde ao conjunto de planos de GO em (002). Os resultados das aplicações são: O eletrodo negativo da Bateria2 com 1% de adição de GO apresentou uma capacidade de descarga de 397,03 mAh/g e maior estabilidade cíclica durante os 30 ciclos. No caso dos imãs, o imã2, com 0,1% em massa de rGO mostrou os maiores valores de Br = 10,42 T, BHmax = 21,19 MGOe, ρ = 7135 kg m-3 e FQ = 0,63.

  • IPEN-DOC 29513

    USSUI, VALTER ; LAZAR, DOLORES R.R. ; LIMA, NELSON B. de ; ARATA, ANELYSE ; RIBEIRO, FABIO N.; DALPIAN, GUSTAVO M.; MARCHI, JULIANA ; PASCHOAL, JOSE O.A. . Room temperature plasticity of zirconia-yttria-titania ceramics: experimental indications and structural modelling. Processing and Application of Ceramics, v. 16, n. 4, p. 367-373, 2022. DOI: 10.2298/PAC2204367U

    Abstract: Yttria-stabilized tetragonal zirconia (Y-TZP) ceramics have excellent mechanical properties. However, such materials cannot undergo plastic deformation at room temperature due to their high hardness and brittleness values, hindering machinability. To overcome these limitations, we propose a zirconia-yttria-titania ceramics, based on zirconia containing 3mol% yttria and up to 15mol% titania. The zirconia-yttria-titania powders were synthesized by co-precipitation method, uniaxially pressed and sintered at 1400°C/5 h. Sample characterizations were carried out by X-ray diffraction, scanning electron microscopy and mechanical properties through Vickers hardness and toughness measurements. Compared to the Y-TZP ceramics, the yttria stabilised tetragonal zirconia ceramics co-doped with 10mol%Ti showed noticeable increase of tetragonality parameter, higher toughness and lower hardness values, indicating plasticity at room temperature. Furthermore, the atomistic simulation by Density Functional Theory methodology suggests the occurrence of spatial arrangement of the atoms, explaining the proposed plasticity.

  • IPEN-DOC 29512

    MARCONDES, POLLYANA; ROSAS, GISELA H.; GONZALEZ, MARIA E.L.; QUEIROZ, ALVARO A.A. de ; MARQUES, PAULO S.. Poly(vinyl alcohol)/poly(glycerol) dendrimer hydrogel mediated green synthesis of silver nanoparticles. Polímeros, v. 32, n. 3, p. 1-9, 2022. DOI: 10.1590/0104-1428.20220025

    Abstract: In this paper, we report the synthesis and evaluation of a poly(vinyl alcohol)/poly(glycerol) dendrimer hydrogel incorporated with green synthesized silver nanoparticles (PVA/PGLD-AgNPs) using Cinnamomum verum extract as the reducting agent (Cz-extract). The Cz-extract was prepared using ultrasonic technique. UV-visible (UV-vis) spectra of Cz-extract confirmed the presence of cinnamaldehyde. PVA/PGLD-AgNPs films were prepared using 5, 10 and 20 mL of Cz-extract and characterized by UV-vis, Fourier transform infrared spectroscopy, Thermogravimetric analysis and X-ray diffraction (XRD). The surface plasmon resonance band in the UV-vis spectra confirmed the formation of AgNPs. XRD pattern confirmed the presence of silver, with average crystallite sizes calculated by Scherrer equal to 13.64 nm, 16.63nm and 20.27 nm for AgNPs prepared with 5 mL, 10 mL and 20 mL of Cz-extract, respectively. AgNPs release kinetic was studied by Korsmeyer– Peppas model. The antimicrobial results revealed that the PVA/PGLD-AgNPs hydrogels showed good antibacterial activity behavior against Escherichia coli.

  • IPEN-DOC 29511

    UMBELINO, U.; LICHTENTHALER, R.; SANTOS, O.C.B.; PIRES, K.C.C.; SERRA, A.S.; SCARDUELLI, V.; LARA, A.L. de; ZEVALLOS, E.O.N.; ZAMORA, J.C.; LEPINE-SZILY, A.; SHORTO, J.M.B. ; ASSUNCAO, M.; ZAGATTO, V.A.B.. Quasielastic scattering of light radioactive and stable projectiles on 9Be. Physical Review C, v. 106, n. 5, p. 054602-1 - 054602-15, 2022. DOI: 10.1103/PhysRevC.106.054602

    Abstract: Quasielastic scattering angular distributions of radioactive (8Li, 7,10Be, and 8,12B) and stable (6,7Li, 9Be, and 11B) projectiles on a 9Be target are presented. The angular distributions have been analyzed by the optical model using Woods-Saxon form factor and São Paulo potential. Total reaction cross sections have been obtained from the optical model analysis and a comparison between different systems is presented. Coupled channels (CC), coupled reaction channels (CRC), and continuum-discretized coupled channels (CDCC) calculations have been performed to investigate the effect of the cluster configuration in the projectile inelastic excitation, breakup, and stripping reactions on the quasielastic angular distributions.

  • IPEN-DOC 29510

    PEDROSA, TULIO de L.; FAROOQ, SAJID ; ARAUJO, RENATO E. de. Selecting high-performance gold nanorods for photothermal conversion. Nanomaterials, v. 12, n. 23, p. 1-11, 2022. DOI: 10.3390/nano12234188

    Abstract: In this work, we establish a new paradigm on identifying optimal arbitrarily shaped metallic nanostructures for photothermal applications. Crucial thermo-optical parameters that rule plasmonic heating are appraised, exploring a nanoparticle size-dependence approach. Our results indicate two distinct figures of merit for the optimization of metallic nanoheaters, under both non-cumulative femtosecond and continuum laser excitation. As a case study, gold nanorods are evaluated for infrared photothermal conversion in water, and the influence of the particle length and diameter are depicted. For non-cumulative femtosecond pulses, efficient photothermal conversion is observed for gold nanorods of small volumes. For continuous wave (CW) excitation at 800 nm and 1064 nm, the optimal gold nanorod dimensions (in water) are, respectively, 90 × 25nm and 150 × 30 nm. Figure of Merit (FoM) variations up to 700% were found considering structures with the same peak wavelength. The effect of collective heating is also appraised. The designing of high-performance plasmonic nanoparticles, based on quantifying FoM, allows a rational use of nanoheaters for localized photothermal applications.

  • IPEN-DOC 29509

    FONSECA, DANIELA P.M. da; CARVALHO, LEANDRO G. de; LIMA, NELSON B. de ; PADILHA, ANGELO F.. Austenite formation in the oxidized layer of ultra-high-strength 13Ni15Co10Mo maraging steel. Metals, v. 12, n. 12, p. 1-10, 2022. DOI: 10.3390/met12122115

    Abstract: Maraging steels are precipitation hardening alloys that can achieve an ultra-high yield strength (~3 GPa), however associated with low toughness. During exposure to high temperatures, an oxidation process occurs on the surface of these steels, generally, the oxides formed are hematite and/or magnetite. The aim of this study was to investigate oxidation on a maraging 13Ni15Co10Mo at annealing temperature of 900 °C. The bulk microstructure was investigated by several complementary techniques and the oxidized surface was characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD). The results showed that the bulk microstructure, at annealed condition, consists of a lath martensite with a hardness of round 400 HV. The most external and oxidized surface contains the oxides hematite, magnetite and kamiokite. Finally, the presence of austenite was detected in the first 2 μm below the surface. Chemical microanalysis indicated that the austenite is stable at room temperature in this region due a composition gradient that makes this region rich in nickel and cobalt. The composition gradient is due atom diffusion during oxides formation. Austenite near to the surface is very convenient as it could avoid crack initiation and propagation, improving toughness.

  • IPEN-DOC 29508

    SILVA, RITA C.A. ; MOREIRA, EDSON G. ; OLIVEIRA, PAULO T.M.S.; THEOPHILO, CAROLINA Y.S. ; SILVA, PAULO S.C. ; SANCHES, THAIS C.; COIMBRA, AMANDA A.; BIANCHI, TICIANA Z.D.; SAIKI, MITIKO . Temporal trends (2006–2019) of metals and nonmetals in livers of great egrets (Ardea alba) from the São Paulo metropolitan region. Journal of Radioanalytical and Nuclear Chemistry, v. 331, n. 12, p. 5701-5707, 2022. DOI: 10.1007/s10967-022-08634-1

    Abstract: Temporal trends (2006–2019) of metals (Cd, Co, Cs, Cu, Fe, Hg, K, Mg, Mn, Na, Rb and Zn) and nonmetals (Br, Cl and Se) were assessed in livers of great egrets (Ardea alba) from São Paulo Metropolitan Region, Brazil. Male and female concentrations were compared and the relation between body mass and contaminant levels was evaluated as well as the risks of contaminant levels for the birds. Large variations were observed for toxic elements (Cd and Hg) over time. Some specimens presented toxic levels of Hg, Cu, Fe and Zn. Females presented lower concentrations of Br, Co, Cs, Rb, Se and Zn, while body mass and Zn were negatively correlated.

  • IPEN-DOC 29507

    SUSSA, FÁBIO V. ; FURLAN, MARCOS R.; VICTORINO, MARCOS; FIGUEIRA, RUBENS C.L.; SILVA, PAULO S.C. . Essential and non‑essential elements in lettuce produced on a rooftop urban garden in São Paulo metropolitan region (Brazil) and assessment of human health risks. Journal of Radioanalytical and Nuclear Chemistry, v. 331, n. 12, p. 5869-5879, 2022. DOI: 10.1007/s10967-022-08661-y

    Abstract: This study evaluated the essential and non-essential elements in lettuce cultivated on a rooftop urban garden in the metropolitan region of São Paulo. In addition, the human health risks associated with the potentially toxic metals based on the estimated daily intake (EDI), the target hazard quotient (THQ), and the possible sources of heavy metal contamination by multivariate statistical were analyzed. The lettuces contain essential macronutrients such as K, Ca, and Mg. The Cd, Cu, and Pb concentrations did not exceed the Brazilian legislation limit. Ba, Ni, Cr, Co, and Pb presented low levels compared to oral reference dose and they may be associated to vehicles emissions. Both EDI and THQ values suggested minimal risk upon consumption of lettuce.

  • IPEN-DOC 29506

    SANTOS, R.F. dos; MUNHOZ, M.G.; MORALLES, M. ; SERRA FILHO, L.A.; BREGANT, M.; SOUZA, F.A. . Development of a fast simulator for GEM-based neutron detectors. Journal of Physics: Conference Series, v. 2374, p. 1-4, 2022. DOI: 10.1088/1742-6596/2374/1/012160

    Abstract: Gas Electron Multiplier (GEM)-based detectors using a layer of 10B as a neutron converter is becoming popular for thermal neutron detection. A common strategy to simulate this kind of detector is based on two frameworks: Geant4 and Gar eld++. The rst one provides the simulation of the nuclear interaction between neutrons and the 10B layer, while the second allows the simulation of the interaction of the reaction products with the detector gas leading to the ionization and excitation of the gas molecules. Given the high ionizing power of these nuclear reaction products, a full simulation is very time consuming and must be optimized to become viable. In this work, we present a strategy to develop a fast simulator based on these two frameworks that will allow us to generate enough data for a proper evaluation of the expected performance and optimization of this kind of detector. We will show the rst results obtained with this tool concentrating on its validation and performance.

  • IPEN-DOC 29505

    KOMATSU, LUIZ G.H. ; CAJADO, GIUSEPPE M. ; PARRA, DUCLERC F. . Effects of silver addition in zinc oxide nanoparticles on films of HMSPP/SEBS against Staphylococcus aureus and Escherichia coli contamination. Journal of Materials Science and Engineering B, v. 12, n. 7-9, p. 108-116, 2022. DOI: 10.17265/2161-6221/2022.7-9.004

    Abstract: In this research we decided to analyze the addition of silver (Ag°) on zinc oxide (ZnO) utilizing two nanoparticles: the synthesized zinc oxide-doped-silver nanoparticles (ZnO/Ag_Lab) utilizing the zinc nitrate as metal precursor for ZnO and silver nitrate as metal precursor for Ag°; and the commercial nanoparticle ZnO/Ag. For the study of application of the nanoparticles, they were processed in the form of films and the polymer utilized was the blend of HMSPP (high melt strength polypropylene) and styrene-ethylene/butadiene-styrene. For the study of nanoparticles, they were submitted to biocide tests against Staphylococcus aureus (ATCC 6538) and Escherichia coli (ATCC8739) and XRD (X-Ray Diffraction). The XRD analysis results indicated, in both of nanoparticles, with the presence of wurtzite phase of ZnO, being that on the commercial nanoparticles the intensity of peak was higher than that of synthesized one, on other hand, the peaks attributed to Ag°, were more intense in the synthesized nanoparticle.

  • IPEN-DOC 29504

    SOUZA, ARMANDO C.; ARISTONE, FLAVIO; SANTANA, ALEXANDRE N.; MIYAI, ADALTON; CIONE, FRANCISCO C. ; TSAKIROPOULOS, PANOS; ROSSI, JESUALDO L. . Characterization and determination of the gamma radiation attenuation coefficient in the W20Cu3Ni metallic alloy to be applied in the transport of radioactive substances. Journal of Materials Research and Technology, v. 21, p. 951-960, 2022. DOI: 10.1016/j.jmrt.2022.09.083

    Abstract: The final responsibility of civil society protection regarding the nuclear sector in every country is a local/national governmental duty. The way this task is wielded changes little from country to country. The principal concern is to reduce the exposure of people to sources that eventually emit radiation. The shield used for this purpose is called biological shielding. The W20Cu3Ni metallic alloy was obtained using W powder as a matrix and the infiltrating elements Cu and Ni and subjected to sintering processes at different temperatures. All samples were analyzed by X-ray diffractometry, scanning electron microscopy (SEM). The main objective of this work is to determine the gamma radiation attenuation coefficients of the W20Cu3Ni metallic alloy subjected to different sintering temperatures. The determination of the alloy attenuation coefficient was performed using an experiment set up with a source of cobalt (Co-60), which emits characteristic energy peaks of 1.173 MeV and 1.332 MeV. The gamma rays are focused to reach the detector and the resulting photons are counted for 1800 s in three situations. Initially, the gamma rays are directed to the detector in a free path. The second experiment consists of using pure tungsten to shield the radiation, i.e., all gamma rays have to pass through it before entering the detector. Finally, the metallic alloy replaces tungsten, and the same measurements are done. Despite the amount of copper and nickel present in the final sample, the results obtained for this new metallic alloy are very satisfactory. The measurements of the gamma attenuation coefficient in the W20Cu3Ni metallic alloy at different temperatures, showed significant results, ie, a difference between 7.08% and 14.63% lower than the attenuation coefficient of pure tungsten used as a reference. Therefore, this new W20Cu3Ni metal alloy has excellent potential for application in shielding systems and in the transport of substances with high nuclear activity used in the production of radioisotopes and radiopharmaceuticals.

  • IPEN-DOC 29502

    SARDO, ARIANE V.N. ; ANDRADE, MAIRA F. ; FIGUEIREDO, ANAELIZA; ROSIN, FLAVIA C.P.; CORREA, LUCIANA; ZEZELL, DENISE M. . Does photobiomodulation affects CK10 and CK14 in oral mucositis radioinduced repair?. International Journal of Molecular Sciences, v. 23, n. 24, p. 1-9, 2022. DOI: 10.3390/ijms232415611

    Abstract: The mechanisms of action of photobiomodulation (PBM) in oral mucositis (OM) are not completely elucidated. To enlighten the role of PBM in the evolution of epithelial maturity in OM ulcers, the present study evaluated the effect of PBM with red ( ) wavelength of 660 nanometers (nm) and infrared of 780 nm in radio-induced OM wounds on the tongue of rats, eight and twenty days after irradiation with single dose of 20 Gy. The percentage area corresponding to positive staining for cytokeratin 10 (CK10) and 14 (CK14) proteins was evaluated in the epithelial area of the lesions, using an immunohistochemical technique (IHC), 8 and 20 days after the induction of lesions, and compared with an untreated control group. CK10 was significantly more expressed in the group treated with 660 nm PBM. CK14 did not show quantitative differences between the groups evaluated. However, whereas in the groups treated with PBM, CK14 was already restricted to the basal layer of the epithelium, as expected in healthy epithelia, in control group it was also expressed in upper layers of the epithelium. In this work, PBM was able to improve epithelial maturity of the repaired OM wound, especially in the 660 nm group.

  • IPEN-DOC 29500

    BORDON, ISABELLA C.; LIMA, MARIANA ; ABESSA, DENIS M.S.; FAVARO, DEBORAH I.T. ; SILVA, PAULO S.C. da ; COTRIM, MARYCEL E.B. ; ULRICH, JOAO C. ; TAKAHASHI, CAMILA K.; SILVA, JOSE R.M.C. da. The Brumadinho mining disaster: immediate impacts of mine tailings 5 days after the dam rupture. Ecotoxicology and Environmental Contamination, v. 17, n. 2, p. 37-45, 2022. DOI: 10.5132/eec.2022.02.05

    Abstract: The rupture of the Córrego do Feijão Dam close to Brumadinho municipality is one of the recent and most devastating environmental disaster in Brazil. This study aims to report the results of metal determinations and acute toxicity assays of mining tailing samples collected 5 days after the dam rupture. Concentrations of As, Cu and Ni in site 1 (close to the dam); concentrations of Cu, Zn and Pb in site 2 (Solo Sagrado) and As, Cd and Cr in the three replicates of site 3 (Mario Campos municipality) were higher than TEL reference value. The Cd concentration in of site 1, and As, Cd and Ni concentrations in of site 2 were higher than the PEL reference value, indicating effective effects of these metals to biota. Corroborating with previous studies, the Uranium contamination was detected close to Solo Sagrado. However, the evaluation of radionuclides came to the absence of relevant radioactivity. Regarding the ecotoxicological assays, survivor percentages of Daphnia similis were lower than the lab control in sites 2 and 3. Thus, results support concerns regarding environmental recovery, which can take years to occur. Monitoring of biota, abiotic and physical-chemical parameters should be performed continually.

  • IPEN-DOC 29499

    PALHARIM, PRISCILA H.; CAIRA, MARIA C.D.A.; GUSMAO, CAROLINA de A.; RAMOS, BRUNO; SANTOS, GABRIEL T. dos; RODRIGUES JUNIOR, ORLANDO ; TEIXEIRA, ANTONIO C.S.C.. Effect of temperature and time on the hydrothermal synthesis of WO3-AgCl photocatalysts regarding photocatalytic activity. Chemical Engineering Research and Design, v. 188, p. 935-953, 2022. DOI: 10.1016/j.cherd.2022.10.045

    Abstract: Heterogeneous photocatalysis is an important and promising alternative for efficient water and wastewater treatment processes. The synthesis of composite materials has attracted attention due to their improved photocatalytic activity and stability. In the present work, composites made of WO3-AgCl were synthesized by a simple one-step hydrothermal method. The evaluation of the effects of reaction temperature and synthesis time for this composite is reported for the first time. The materials were characterized by XRD, SEM, TEM, EDS, BET, UV–vis DRS, XPS, EPR and PL. All photocatalysts showed broad-spectrum activity due to their strong absorption in the UV region and some absorption in the visible region. The morphology of the materials was highly influenced by the synthesis temperature and time, which affected the photocatalytic efficiency. All materials exhibited good photocatalytic activity under simulated sunlight, with maximum acetaminophen removal of 99.6% for the catalyst synthesized at 120 °C and 12 h. Stability tests showed considerable stability after four cycles. The main reactive species participating in the photodegradation reaction were found to be O2•-> h+ ∼ •OH. The heterojunction formed between AgCl and WO3 plays an important role in the photocatalytic activity, especially when the AgCl surface is not completely covered by WO3.

  • IPEN-DOC 29498

    BEZERRA, RITA de C.F.; MOTA, GABRIELA; VIDAL, RUTH M.B.; CARMO, JOSE V. do; SARAIVA, GILBERTO D.; CAMPOS, ADRIANA; OLIVEIRA, ALCINEIA C.; LANG, ROSSANO; OTUBO, LARISSA ; JIMENEZ, JOSE J.; RODRIGUEZ-CASTELLON, ENRIQUE. Effect of basic promoters on porous supported alumina catalysts for acetins production. Catalysts, v. 12, n. 12, p. 1-23, 2022. DOI: 10.3390/catal12121616

    Abstract: A facile strategy for the design of porous supports was obtained by modifying the sol-gel method followed by the wet impregnation technique. In this respect, herein, the acidity of the -Al2O3 phase was modulated by adding basic MgO, La2O3 or ZnO promoters to form binary supported catalysts. The Ni and Co dispersion on the supports associated with their tunable acidity and morphologies resulted in highly porous supported alumina-based catalysts. The physicochemical properties of the solids were comprehensively investigated by XRD, textural properties, Raman and FTIR spectroscopy, SEM-EDS, TEM, EPR and XPS analyses. The catalytic performances in the esterification of glycerol in the presence of acetic acid (EG) for the acetins production were evaluated. The highly dispersed NiO and Co3O4 active species on binary porous supports produced synergistic effects appearing to be the reason for the activity of the solids in the EG reaction. Under the optimized reaction conditions, NiCo/MgO-Al2O3 was found to be a robust solid with superior catalytic performance and improved stability in four reaction cycles with 65.0% of glycerol conversion with an exclusive selectivity of 53% for triacetin. The presence of Co2+/Co3+ and Ni2+ strongly interacting with the spinel -Al2O3 and MgAl2O4 phases, the latter having a large number of lattice oxygen species, was considered another active component besides those of Ni and Co in the esterification of glycerol.

  • IPEN-DOC 29497

    TORRECILHA, JEFFERSON K. ; GOUVEA, PAULO F. de M. ; COTRIM, MARYCEL E.B. ; SILVA, PAULO S.C. da . Disponibilidade de elementos traço para absorção cutânea em tratamentos com a lama negra de Peruíbe / Availability of trace elements for skin absorption in treatments using Peruíbe black mud. Cadernos de Naturologia e Terapias Complementares, v. 10, n. 18, p. 17-26, 2022.

    Abstract: Introdução: No Brasil, o uso de recursos naturais passou a fazer parte do Sistema Único de Saúde (SUS) com a implantação da “Política Nacional de Práticas Integrativas e Complementares” e a Lama Negra, localizada na cidade de Peruíbe, Estado de São Paulo, tem sido amplamente utilizado para tratamentos terapêuticos, por exemplo psoríase, dermatite periférica, neuropatia, acne e seborreia, mialgia, artrite e processos reumáticos não articulares. Objetivo: O objetivo deste estudo foi verificar a mobilidade dos elementos da Lama Negra de Peruíbe, e avaliar quais (benéficos ou tóxicos) estão disponíveis para transferência ao paciente durante o tratamento terapêutico tópico. Para tanto, foram empregados dois métodos de extração: procedimento de extração sequencial e extração única com emprego de suor artificial. Métodos: Dois métodos de extração foram empregados para medir os elementos extraídos: espectroscopia de emissão atômica com plasma indutivamente acoplado e espectrometria de absorção atômica com forno de grafite. Resultados e discussão: Os resultados mostraram que os elementos Ca, Cd, Mg, Mn e Na são altamente extraídos na fração trocável e resultados semelhantes foram observados na extração com suor artificial, entretanto, isso pode não ser um problema durante o tratamento terapêutico. Conclusão: Todos os outros elementos investigados foram extraídos em baixas concentrações, indicando que os efeitos adversos à saúde devem ser desprezíveis, embora até o momento haja pouca ou nenhuma evidência de absorção pela pele.

  • IPEN-DOC 29496

    MARQUES, RODOLFO F.; QUINTILIO, WAGNER; KNIRSCH, MARCOS C.; FUCASE, TAMARA M. ; SPENCER, PATRICK J. ; STEPHANO, MARCO A.. Action of bromelain and ficin on horse anti Bothrops sp venom antibodies. Brazilian Journal of Pharmaceutical Sciences, v. 58, p. 1-9, 2022. DOI: 10.1590/s2175-97902022e20867

    Abstract: The treatment with hyperimmune sera constitute the only specific and effective therapy available against snakebite envenomation, most common in developing countries. Serum quality is an important factor on patient recovery time and in the incidence of death and permanent disability. To date, most sera consist of pepsin digested IgG antibodies harvested from hyperimmune animals. The use of animal derived enzymes, such as pepsin, to digest IgG, constitute a source of adventitious agents and contaminants, such as porcine circovirus. The present study aims to evaluate the use of the plant derived enzymes bromelain and ficin, as an alternative to pepsin. To this purpose, horse serum immunized against Bothrops venoms was purified with caprylic acid and digested with bromelain or ficin. SDS-PAGE results evidence the formation of F(ab)’2 fragments and suggest that a digestion time superior to 8 hours may be required to completely digest the antibodies with bromelain or ficin. F(ab)’2 fragments obtained by digestion with either bromelain or ficin digestion preserved the ability to recognize Bothrops sp. venom in western blotting assays. Therefore, both enzymes are suitable for use in large-scale production, minimizing contamination risks and increasing safety and efficiency of serotherapy treatments.

  • IPEN-DOC 29495

    LINO, JULIANA dos S. ; ANDRADE, DELVONEI A. de . Improving contaminated land data communication through the developing of an environmental indicator / Desenvolvimento de um indicador ambiental para aprimorar a comunicação de dados sobre áreas contaminadas. Brazilian Journal of Development, v. 8, n. 12, p. 78628-78645, 2022. DOI: 10.34117/bjdv8n12-120

    Abstract: Environment contamination is a widespread problem in all countries around the world. Contaminated sites are consequence of land use and occupation without environmental concerns, and it can cause contamination of superficial soil, subsoil, and groundwater. This issue affects urban planning, human health as well natural resource availability. The management of contaminated land data and its communication to stakeholders is a significant driver to achieve sustainable urban planning, promoting equally sustainable cities and communities. Therefore, tools to improve comprehension of environmental quality of cities is essential to face this challenge. Here, we develop an environmental indicator to analyze contaminated land data and communicate its complexity to non-technical stakeholders. The indicator developed, adopts 15 variables and considering three parameters: polluting substance concentration, affected environmental matrices, and the environmental behavior of the polluting substance. A dataset has been elaborated containing information about 25 contaminated sites of Lapa District, the pilot area of São Paulo city, and the environmental indicator was applied, resulting in four environmental contamination levels: low, moderate, high, and remarkably high degrees, existing in an individually site.

  • IPEN-DOC 29494

    NAUS, STIJN; DOMINGUES, LUCAS G. ; KROL, MAARTEN; LUIJKX, INGRID T.; GATTI, LUCIANA V. ; MILLER, JOHN B.; GLOOR, EMANUEL; BASU, SOURISH; CORREIA, CAIO ; KOREN, GERBRAND; WORDEN, HELEN M.; FLEMMING, JOHANNES; PETRON, GABRIELLE; PETERS, WOUTER. Sixteen years of MOPITT satellite data strongly constrain Amazon CO fire emissions. Atmospheric Chemistry and Physics, v. 22, n. 22, p. 14735-14750, 2022. DOI: 10.5194/acp-22-14735-2022

    Abstract: Despite the consensus on the overall downward trend in Amazon forest loss in the previous decade, estimates of yearly carbon emissions from deforestation still vary widely. Estimated carbon emissions are currently often based on data from local logging activity reports, changes in remotely sensed biomass, and remote detection of fire hotspots and burned area. Here, we use 16 years of satellite-derived carbon monoxide (CO) columns to constrain fire CO emissions from the Amazon Basin between 2003 and 2018. Through data assimilation, we produce 3 d average maps of fire CO emissions over the Amazon, which we verified to be consistent with a long-term monitoring programme of aircraft CO profiles over five sites in the Amazon. Our new product independently confirms a long-term decrease of 54% in deforestation-related CO emissions over the study period. Interannual variability is large, with known anomalously dry years showing a more than 4-fold increase in basin-wide fire emissions relative to wet years. At the level of individual Brazilian states, we find that both soil moisture anomalies and human ignitions determine fire activity, suggesting that future carbon release from fires depends on drought intensity as much as on continued forest protection. Our study shows that the atmospheric composition perspective on deforestation is a valuable additional monitoring instrument that complements existing bottom-up and remote sensing methods for land-use change. Extension of such a perspective to an operational framework is timely considering the observed increased fire intensity in the Amazon Basin between 2019 and 2021.

  • IPEN-DOC 29493

    PASQUALINI, ALEXANDRE A. ; ARTHUR, VALTER ; SCHIAVOLIN, MICHELEN B.; ABREU, MARINA R. de; CAMARGO-MATHIAS, MARIA I.. Histological evaluation of Rhipicephalus (Boophilus) microplus tick ovaries subjected to cobalt-60 ionizing radiation. Applied Veterinary Research, v. 1, n. 2, p. 1-7, 2022. DOI: 10.31893/avr.2022007

    Abstract: Females of Rhipicephalus (Boophilus) microplus ticks ingurgitated and in the prepost phase were submitted to doses of 0, 5, 10, 15, 20 and 25 Gy of Cobalt-60 with the aim of evaluating their effects on ovarian morphohistology with consequent establishment of the degree of damage caused to the reproductive organs of this species. For this purpose, 24 hours after exposure to Co-60 (142 Gy/h) the ectoparasites were dissected and had their ovaries removed and prepared for histology with haematoxylin and eosin staining. The results obtained showed that the 5 Gy dose radiation had a morphological aspect similar to the control standard adopted. The histological sections related to doses of 10 and 15 Gy did not cause many changes in the ovaries, except that changes were observed in the calf granules (size, distribution and staining pattern), as well as the extensive presence of cytoplasmic vacuoles in the ovocytes, especially in the region that makes contact with the ovocyte/pedicel, suggesting the occurrence of changes also in the physiology of the organ. In the ovaries exposed to doses of 20 and 25 Gy, severe alterations were observed in the organ as a whole, as well as in the germ cells (oocytes) which suffered alterations in size and shape, distribution of calf granules, involvement of the DNA present in the germinal vesicle (oocyte nuclei), besides the extensive cytoplasmic vacuolization, alterations which made the maturation of these cells impossible and consequently inhibited the production of new individuals.

  • IPEN-DOC 29492

    ARTHUR, PAULA B. ; LEANDRO, RODRIGO S.R. ; HARDER, MARCIA N.C.; ARTHUR, VALTER . Animal welfare provisions in cattery: an observational study. Applied Veterinary Research, v. 1, n. 4, p. 1-4, 2022. DOI: 10.31893/avr.2022020

    Abstract: The present study had the objective of proposing adaptations for a permanent housing environment for neutered cats. Priorities and management practices were characterized by better animals health and quality of life. An animal observation survey was carried out on two different types of catteries: A, where the animals had an environment with greater freedom of movement, and cattery B, with animals with a reduced environment. The problems encountered in each were observed, such as sanitary, nutritional, and especially environmental management. Behavior was taken into account, according to the environment experienced by domestic cats castrated in confinement in the two different types of catteries. Based on the frequency and behavioral sequence of the groups analyzed, it was concluded that the environment of the cattery A promoted greater well-being of the animals.

  • IPEN-DOC 29491

    REIS, FABRICIO C. ; ARAUJO, MARCIO M. de ; ROMANO, JAMILE I.S. ; POTENZA, MARCOS R.; ARTHUR, VALTER. Dose letal imediata de radiação gama para espécies de carunchos do feijão utilizando irradiador multipropósito / Immediate lethal dose of gamma radiation for three species of weevil of bean used multipurpose irradiator. Agrarian, v. 15, n. 55, 2022. DOI: 10.30612/agrarian.v15i55.15712

    Abstract: Este trabalho teve como objetivo determinar a dose letal imediata de radiação gama do Cobalto-60 (60Co) para Acanthocelides obtectus, Zabrotes subfasciatus e Callosobruchus maculatus utilizando o irradiador multipropósito IPEN/CNEN. Os insetos foram mantidos em grãos de feijão das variedades Phaseolus vulgaris e Vigna unguiculata acondicionados em potes plásticos. Utilizando-se o delineamento experimental inteiramente casualizado, foram selecionados 20 indivíduos adultos com idade entre 3–7 dias, para cada repetição, num total de 5 repetições por tratamento. Foram aplicadas doses crescentes de radiação gama até atingir a mortalidade total dos insetos. A dose de 3,0 kGy foi estabelecida para controle imediato dos insetos adultos das espécies estudadas.

  • IPEN-DOC 29471

    MUCCILLO, REGINALDO ; CARVALHO, SABRINA G.M. ; DENALDI, RAFAEL L. ; MUCCILLO, ELIANA N.S. . Development of stabilized zirconia–alkali salts dual membranes for carbon dioxide capture. International Journal of Applied Ceramic Technology, v. 20, n. 2, p. 951-958, 2023. DOI: 10.1111/ijac.14290

    Abstract: Molten Na2CO3–K2CO3 (NKC, 56–44 mol%) eutectic compositions were vacuum-impregnated, at the eutectic temperature, into two porous ZrO2:8.6 mol% MgO (magnesium-partially stabilized zirconia, MgPSZ) and ZrO2:8 mol% Y2O2 (yttria-fully stabilized zirconia, 8YSZ) ceramics. Thermogravimetric analyses were performed in mixtures of that composition with MgPSZ and 8YSZ ceramic powders. Before impregnation, porosity was achieved in the two compounds by addition and thermal removal of 30 vol.% NKC. To ascertain the carbonates had filled up through the ceramic body, both sides of the parallel and fracture surfaces of the disk-shaped impregnated compositions were observed in a scanning electron microscope and analyzed by energy-dispersive X-ray spectroscopy. The electrical conductivity of the two ceramics, before and after impregnation, was evaluated by electrochemical impedance spectroscopy in the 5 Hz–13 MHz frequency range from approximately 530 to 740°C. The permeation of the carbonate ions through the membranes via the eutectic composition was assessed by the threshold temperatures of the onset of the carbonate ion percolation. The objectives were to prepare dual-phase membranes for the separation of carbon dioxide and for the development of carbon dioxide sensors.

    Palavras-Chave: zirconium compounds; alkali metal compounds; ceramics; membranes; carbon dioxide; zirconium oxides

  • IPEN-DOC 29330

    SOARES, NAYANI G. de L.; GUSHIKEN, KAROLINA Y.; FREITAS, GUSTAVO R. ; JOAQUIM, ARIANE, A.M.; RODRIGUES, GUILHERME O.. Fatores influentes na densidade mamográfica e seu impacto no Câncer de mama / Influencing factors in mammographic density and its impact on Breast cancer. Brazilian Journal of Health Review, v. 6, n. 1, p. 1222-1238, 2023. DOI: 10.34119/bjhrv6n1-093

    Abstract: A mama é composta por tecido adiposo, tecido fibroso de sustentação e tecido glandular associados a vasos sanguíneos, linfáticos e nervos. Um fator de risco para o surgimento do câncer de mama é o aumento na densidade mamográfica no tecido mamário, a densidade mamográfica corresponde à quantidade de tecido fibroglandular nas mamas, apresentando-se como um tecido radiopaco, e possui quatro classificações, segundo o Breast Imaging Reporting and Data System (BI-RADS). Mulheres com mamas densas apresentam um risco de quatro a seis vezes maior de desenvolver carcinogênese. O carcinoma de mama pode ser dividido conforme sua localização em in situ ou infiltrativo e a mamografia é o exame mais comum na detecção de câncer de mama. Esta revisão tem o objetivo de investigar os fatores que modulam a densidade mamográfica, e como esses fatores se relacionam com o aumento de mamas densas. A pesquisa bibliográfica foi realizada pelo PubMed - NCBI num período de nove anos em inglês, utilizando como palavras-chaves “densidade mamográfica”, “câncer de mama” e “ mamografia”. Alguns fatores podem influenciar na densidade mamográfica como por exemplo herdabilidade, raça e etnia, dieta, terapias de reposição hormonal, ingestão de álcool, estilo de vida, fatores reprodutivos e hormonais - como menopausa, paridade, idade ao primeiro nascimento e idade da menarca - tamanho corporal, microcalcificações e faixa etária. O câncer de mama também é menos incidente em mulheres afro-americanas e indígenas, isso pode ser explicado pelos hábitos de vida dessa população, por exemplo: primeira gravidez mais cedo, multiparidade, amamentação prolongada e ausência de terapias hormonais. Fatores considerados de variável categórica e contínua, como ingestão de álcool, tabagismo e atividade física ainda não estão bem estabelecidas suas relações com o aumento ou diminuição da densidade mamográfica, o que requer mais estudos para chegar a resultados conclusivos. A mamografia ainda é a forma mais comum do rastreamento de câncer de mama, porém sua sensibilidade é menor quando se trata de mamas densas, por conta disso estão sendo utilizados e desenvolvidos novos métodos de diagnóstico por imagem como: ressonância magnética, ultrassonografia, tomossíntese digital da mama e a ultrassonografia automatizada das mamas (ABUS). Essa revisão literária traz estudos detalhados que visam compreender os fatores que levam ao aumento da densidade mamográfica, permitindo o melhor diagnóstico e mapeamento de grupos de risco, o que possibilita amenizar as consequências dessas modificações, a fim de fornecer medidas preventivas contra o câncer de mama.

    Palavras-Chave: mammary glands; density; neoplams; carcinomas; biomedical radiography; health hazards; diagnosis

  • IPEN-DOC 29321

    FERREIRA, ALEXANDRE D.C.; UESO, INGRID; TRINDADE, NELSON B.; ARAUJO, MAURICIO C.; BORRELY, SUELI I. ; ROSA, JORGE M. . Estudo sobre o consumo de energia e das propriedades físico-químicas na termofixação de tecidos de poliamida 6.6. Revista Química Têxtil, v. 46, n. 142, p. 6-14, 2022.

    Abstract: Estudou-se o consumo de energia e as propriedades fisico-químicas de um tecido de malha de poliamida 66, aplicando-se a metodologia de superfícies de resposta (MSR) na obtenção de parâmetros ideais de termofixação , Apesar de apresentar maior porcentagem de encolhimento em 0,933%, os consumos de corante e energia obtidos pelo modelo matemático aplicado com parâmetros de 30 s a 178 ºC foram 0,227 g kg-1 e 7,43 x 105 J kg-1 menores do que os valores do processo que apresentou menor valor de encolhimento, efetuado com parâmetros de 45 s a 190 ºC, demonstrando que a ferramenta pode ser aplicada na predição de parâmetros ideais de termofixação no substrato estudado.

    Palavras-Chave: polyamides; dyes; physical chemistry; energy consumption; textiles; polymers

  • IPEN-DOC 29314

    ROQUE, ACASSIO M.; SARTORI, CARLOS A. . Compatibilidade e resiliência eletromagnética em sistemas elétricos e eletrônicos. Revista O Setor Elétrico, v. 16, n. 184, p. 52-55, 2022.

    Palavras-Chave: electromagnetism; electronic equipment; electrical equipment; electromagnetic interactions; compatibility; interference

  • IPEN-DOC 29313

    FALOPPA, MONICA A.; CORREIA, JOSELENE B.F.; SILVA, THAIS S.; DANIEL, BRUNA R.; ALMEIDA, RAQUEL S.R.; SPOTO, MARTA H.F.; ROSA, JORGE M. ; BORRELY, SUELI I. . Study of the water and energy consumptions in the dyeing of cotton with Curcuma Longa by pad-batch process using response surface methodology. Journal of Natural Fibers, v. 19, n. 13, p. 6797-6809, 2022. DOI: 10.1080/15440478.2021.1932677

    Abstract: Mathematical modeling was employed in order to optimize pad-batch process using C. longa natural dyestuff applied in dyeing of cotton, against the conventional dyeing by exhaustion with the same dyestuff under best applications parameters recommended by dyestuff supplier. Ecological costs, consumption of water, electrical, and thermal energy, were assessed. The application of the model in the studied process versus the conventional process demonstrated that is possible to obtain an economy of 1.418 × 10(6) J kg(‒1) of energy, in addition to an economy of 95% in water consumption, without significant detriment in the color fastness assessed.

    Palavras-Chave: dyes; textiles; cotton; cost; ecology; water use; energy consumption; curcumin

  • IPEN-DOC 29312

    SOUZA, CARLA D. de ; FREITAS, GUSTAVO R. ; MEDEIROS, ROGERIO F.; RAMALHO, ERCILIA; RODRIGUES, SERGIO C.; RODRIGUES, GUILHERME O.. Protocol for reducing radiation exposure during pediatricthoracic radiography. Journal of Medical Imaging and Radiation Sciences, v. 53, n. 3, p. 437-443, 2022. DOI: 10.1016/j.jmir.2022.05.012

    Abstract: Introduction: This work aims to assess if the anode position during chest radiography of pediatric patients with heart congenital disease (HCD) influences medical image results. The approach is to reverse the orientation of the x-ray tube, with the anode end directed towards the patient's face (anode-heel effect). Methods: Five specialists analyzed 48 images, 24 from the control group (CG) and 24 with the anode end directed towards the patients' face (experimental group, EC). An ionization chamber was used to assess radiation dose received by sensitive organs. Results: The specialists considered both CG and EC images acceptable. But, the EC group's dose evaluation revealed that the thyroid received 12% less radiation and the gonads presented a 5.9% reduction. Based on the results, a new protocol was developed. Discussion/conclusion: The standardization of radiographic imaging procedures will reduce acquisition errors, resulting in adequate images in pediatric patients with HCD with less radiation dose, thus increasing patient safety and extending the life of the equipment.

    Palavras-Chave: safety; patients; pediatrics; recommendations; radiation doses; x-ray equipment; biomedical radiography; anodes; radiation absorption analysis

  • IPEN-DOC 29290

    MACHADO, MARINA ; BAIUTTI, FEDERICO; BERNADET, LUCILE; MORATA, ALEX; NUNEZ, MARC; OUWELTJES, JAN P.; FONSECA, FABIO C. ; TORRELL, MARC.; TARANCON, ALBERT. Functional thin films as cathode/electrolyte interlayers: a strategy to enhance the performance and durability of solid oxide fuel cells. Journal of Materials Chemistry A, v. 10, n. 33, p. 17317-17325, 2022. DOI: 10.1039/d2ta03641j

    Abstract: Electrochemical devices such as solid oxide fuel cells (SOFC) may greatly benefit from the implementation of nanoengineered thin-film multifunctional layers providing, alongside enhanced electrochemical activity, improved mechanical and long-term stability. In this study, an ultrathin (400 nm) bilayer of samarium-doped ceria and a self-assembled nanocomposite made of Sm0.2Ce0.8O1.9-La0.8Sr0.2MnO3-δ was fabricated by pulsed laser deposition and is employed as a functional oxygen electrode in an anode-supported solid oxide fuel cell. Introducing the functional bilayer in the cell's architecture results in a simple processing technique for the fabrication of high-performance fuel cells (power density 1.0 W cm−2 at 0.7 V and 750 °C). Durability tests were carried out for up to 1500 h, showing a small degradation under extreme operating conditions of 1 A cm−2, while a stable behaviour at 0.5 A cm−2 (2.8% Vin kh−1). Post-test analyses, including scanning and transmission electron microscopy and electrochemical impedance spectroscopy, demonstrate that the nanoengineered thin film layers remain mostly morphologically stable after the operation.

  • IPEN-DOC 29289

    KAIRALLA, ELENI C. ; BRESSIANI, JOSE C. ; BRESSIANI, ANA H. de A. ; RIBELA, MARIA T. de C.P. ; HIGA, OLGA Z. ; QUEIROZ, ÁLVARO A.A. de . Physicochemical and biological properties of nanohydroxyapatite grafted with star-shaped poly(ε-caprolactone). Journal of Biomaterials Science, Polymer Edition, v. 33, n. 18, p. 2353-2384, 2022. DOI: 10.1080/09205063.2022.2104599

    Abstract: To overcome the disadvantages generated by the lack of interfacial bonding between hydroxyapatite nanocrystals (HAPN) and agglomeration of particles in the development of biodegradable nanocomposites a chemical grafting method was applied to modify the surface of HAPN through grafting of the three-arms star-shaped poly(ε-caprolactone) (SPCL) onto the nanoparticles. The chemical grafting of SPCL onto HAPN (SPCL-g-HAPN) has been investigated using Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy (TEM), photoelectron spectroscopy, X-ray diffraction, zeta potential (ZP) and contact angle (CA). TEM micrographs of the SPCL-g-HAPN revealed the existence of hybrid organic/inorganic (O/I) nanoscale domains. The results of albumin (HSA) and fibrinogen (HFb) adsorption indicate resistance to HFb adsorption by SPCL-g-HAPN relatively to unmodified HAPN. The ZP and CA measurement suggest a heterogeneous topology for SPCL-g-HAPN likely due to the existence of hydrophobic-hydrophilic regions on the nanocomposite surface. The enzyme degradation by cholesterol esterase and lipase indicates that the rates of hydrolysis for SPCL-g-HAPN were very slow relative to the SPCL/HAPN blends. The in vitro biological studies showed that the human osteoblast-like cells (MG-63) cells had normal morphology and they were able to attach and spread out on SPCL-g-HAPN surfaces. A higher overall cellular proliferation was observed on SPCL-g-HAPN scaffolds compared to pure HAPN or SPCL materials.

    Palavras-Chave: organic polymers; nanocrystals; hydroxy compounds; biodegradation; nanocomposites; apatites; protein; adsorption

  • IPEN-DOC 29288

    SANTOS, SILAS C. ; RODRIGUES JUNIOR, ORLANDO ; CAMPOS, LETICIA L. . A glance at dysprosium oxide free powders. Current Materials Science, v. 16, n. 1, p. 85-94, 2023. DOI: 10.2174/2666145415666220602152634

    Abstract: Background: Dysprosium oxide (Dy2O3) gathers a set of profitable properties with a wide range of applications, including energy and astronomy. Particular characteristics directly influence the formation and features of materials by colloidal processing. The main purpose of this paper is to carry out a powder characterization of Dy2O3particles. The findings reported are worthwhile parameters to advance in the formulation of new smart materials for radiation dosimetry. Methods: Dy2O3 powders were characterized by XRD, PCS, SEM, pynometric density (ρ), FTIR, ICP, EPR, and zeta potential (ζ). Results: The powdered samples exhibited as main features a cubic C-type structure following the RE-polymorphic diagram, a mean particle size distribution with d50 of 389nm, and pynometric density of The EPR spectra revealed three distinct peaks, p1, p2, and p3, with the following g values: 2.3121, 2.1565, and 2.1146. In addition, the nanoparticles presented high stability at pH 5.5 and a ζ-value of |49.7|mV. Conclusion: The powder characterization of Dy2O3 powders was reported. The results achieved in this study may be considered worthwhile parameters to advance in the formulation of Dy2O3- based materials for radiation dosimetry.

    Palavras-Chave: dysprosium oxides; rare earths; nanoparticles; dosimetry; ceramics

  • IPEN-DOC 29215

    ASHRAF, NERMEEN; RODRIGUES, EDUARDO S.; ALMEIDA, EDUARDO de; MONTANHA, GABRIEL S.; ABREU-JUNIOR, CASSIO H.; VITOVA, MILADA; GARCIA, RAFAEL H.L. ; KUPPER, HENDRIK; CARVALHO, HUDSON W.P. de. Identification of potential plant species hyperaccumulating light rare earth elements (LREE) in a mining area in Minas Gerais, Brazil. Environmental Science and Pollution Research, v. 29, n. 60, p. 90779-90790, 2022. DOI: 10.1007/s11356-022-22009-9

    Abstract: Phytoextraction of rare earth elements (REE) from contaminated soils has gained importance during the last few decades. The Poços de Caldas municipality in Brazil is known for its mineral richness, including large reserves of REE. In this study, we report light REE (La, Ce, Sm, Pr, and Nd) in soils and plants collected in an area. Composite soil samples and plant individuals were collected, and total concentrations of LREE in soils were determined by wavelength dispersive X-ray fluorescence (WDXRF). The plant available LREE concentrations in soils were estimated upon the acetic acid method (F1 fractions) of the stepwise sequential extraction procedure, together with plant content that was analysed by inductively coupled plasma mass spectrometry (ICP-MS). The total sum concentrations of tested LREE in soils varied from 5.6 up to 37.9 g kg−1, the bioavailable fraction was ca. 1%, and a linear relationship was found between them. The only exception was Sm, whose availability was lesser and did not show a linear relationship. The concentration of LREE in non-accumulator plants varied from 1.3–950 mg kg−1 for Ce, La 1.1–99 mg kg−1, Sm 0.04–9.31 mg kg−1, Pr 0.1–24.1 mg kg−1, and Nd 0.55–81 mg kg−1. The concentration of LREE among shoots did not show a linear relation either with the available fraction or total content. The screening also revealed Christella dentata (Forssk.) Brownsey & Jermy, Thelypteridaceae family, as a promising hyperaccumulator species. The concentrations of LREE among shoots of six individuals of this species were in the ranges from 115 to 1872 mg kg−1 for Ce, La 190–703 mg kg−1, Sm 9–48 mg kg−1, Pr 32–144 mg kg−1, and Nd 105–478 mg kg−1.

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A pesquisa no RD utiliza os recursos de busca da maioria das bases de dados. No entanto algumas dicas podem auxiliar para obter um resultado mais pertinente.

É possível efetuar a busca de um autor ou um termo em todo o RD, por meio do Buscar no Repositório , isto é, o termo solicitado será localizado em qualquer campo do RD. No entanto esse tipo de pesquisa não é recomendada a não ser que se deseje um resultado amplo e generalizado.

A pesquisa apresentará melhor resultado selecionando um dos filtros disponíveis em Navegar

Os filtros disponíveis em Navegar tais como: Coleções, Ano de publicação, Títulos, Assuntos, Autores, Revista, Tipo de publicação são autoexplicativos. O filtro, Autores IPEN apresenta uma relação com os autores vinculados ao IPEN; o ID Autor IPEN diz respeito ao número único de identificação de cada autor constante no RD e sob o qual estão agrupados todos os seus trabalhos independente das variáveis do seu nome; Tipo de acesso diz respeito à acessibilidade do documento, isto é , sujeito as leis de direitos autorais, ID RT apresenta a relação dos relatórios técnicos, restritos para consulta das comunidades indicadas.

A opção Busca avançada utiliza os conectores da lógica boleana, é o melhor recurso para combinar chaves de busca e obter documentos relevantes à sua pesquisa, utilize os filtros apresentados na caixa de seleção para refinar o resultado de busca. Pode-se adicionar vários filtros a uma mesma busca.


Buscar os artigos apresentados em um evento internacional de 2015, sobre loss of coolant, do autor Maprelian.

Autor: Maprelian

Título: loss of coolant

Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

Para indexação dos documentos é utilizado o Thesaurus do INIS, especializado na área nuclear e utilizado em todos os países membros da International Atomic Energy Agency – IAEA , por esse motivo, utilize os termos de busca de assunto em inglês; isto não exclui a busca livre por palavras, apenas o resultado pode não ser tão relevante ou pertinente.

95% do RD apresenta o texto completo do documento com livre acesso, para aqueles que apresentam o significa que e o documento está sujeito as leis de direitos autorais, solicita-se nesses casos contatar a Biblioteca do IPEN, .

Ao efetuar a busca por um autor o RD apresentará uma relação de todos os trabalhos depositados no RD. No lado direito da tela são apresentados os coautores com o número de trabalhos produzidos em conjunto bem como os assuntos abordados e os respectivos anos de publicação agrupados.

O RD disponibiliza um quadro estatístico de produtividade, onde é possível visualizar o número dos trabalhos agrupados por tipo de coleção, a medida que estão sendo depositados no RD.

Na página inicial nas referências são sinalizados todos os autores IPEN, ao clicar nesse símbolo será aberta uma nova página correspondente à aquele autor – trata-se da página do pesquisador.

Na página do pesquisador, é possível verificar, as variações do nome, a relação de todos os trabalhos com texto completo bem como um quadro resumo numérico; há links para o Currículo Lattes e o Google Acadêmico ( quando esse for informado).



O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

1. Portaria IPEN-CNEN/SP nº 387, que estabeleceu os princípios que nortearam a criação do RDI, clique aqui.

2. A experiência do Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP) na criação de um Repositório Digital Institucional – RDI, clique aqui.

O Repositório Digital do IPEN é um equipamento institucional de acesso aberto, criado com o objetivo de reunir, preservar, disponibilizar e conferir maior visibilidade à Produção Científica publicada pelo Instituto, desde sua criação em 1956.

Operando, inicialmente como uma base de dados referencial o Repositório foi disponibilizado na atual plataforma, em junho de 2015. No Repositório está disponível o acesso ao conteúdo digital de artigos de periódicos, eventos, nacionais e internacionais, livros, capítulos, dissertações, teses e relatórios técnicos.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.