Reposiório IPEN: Recent submissions

  • IPEN-DOC 27901

    ABREU, R.T. ; ANGELOCCI, L.V. ; NOGUEIRA, B.R. ; SANTOS, H.N. ; ZEITUNI, C.A. ; ROSTELATO, M.E.C.M. . Anisotropy function of a new 192-Ir brachytherapy source. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-15, 2021. DOI: 10.15392/bjrs.v9i1A.1506

    Abstract: Brachytherapy is a type of radiotherapy that uses radioactive sources (seeds, wires, among others) close to the tumor. Is important to provide a detailed description of seed dosimetry, so only the tumor will be irradiated avoiding unnecessary dose on adjacent organs and structures. To evaluate the dosimetric parameter of the anisotropy function for a new brachytherapy source, this work proposes the use of microcube TLD-100 dosimeters to find the dose rate using the AAPM Task Group 43 protocol (TG-43). The anisotropy function represents dose distribution around the source and has a major role for characterization of a new iridium source being implemented in Brazil. The value of D(r,θ) was measured using Solid Water phantoms, r value being the distance from the geometric center of the source to the position of the dosimeter on the phantom, and θ being the angle formed between the longitudinal axis of the source and the line connecting the geometric center to the TLD. Monte Carlo calculations were performed to evaluate the anisotropy function to validate the experimental measurements. For each distance value (r), an anisotropy function was plotted (1.0, 2.0, 3.0, 4.0, 5.0, and 10.0 cm). The results obtained with Monte Carlo calculations agreed ±2% with the experimental values for r greater than 3.0 cm, so these results show a good distribution of dose around the seed considering the high energy of 192-Ir (average of 380 KeV) and encapsulation thickness.

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  • IPEN-DOC 27900

    SOUZA, A.P.S. ; OLIVEIRA, L.P. de ; YOKAICHIYA, F.; GENEZINI, F.A. ; FRANCO, M.K.K.D. . A diffractometer project for Brazilian Multipurpose Reactor (RMB): McStas simulations and instrument optimization. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-17, 2021. DOI: 10.15392/bjrs.v9i1A.1499

    Abstract: The high-resolution diffractometer is one of the first instruments of the set of 15 priority neutron scattering instruments to be installed at the Brazilian Multipurpose Reactor (RMB). A basic project of this instrument consists of the existence of three guides through which neutrons pass from source to sample to guarantee maximum neutron flux at the sample position. In this study, we investigate guide geometry performance considering fixed diffractometer geometry and spatial arrangement. Comparisons between different guide shapes and supermirrors are performed using software based on the Monte Carlo method, McStas. Our conclusion shows that a better solution is splitting the initial flux into two different guides to obtain the maximum flux at the sample position.

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  • IPEN-DOC 27899

    ALENCAR, C.S.L. ; PAIVA, A.R.N. ; SILVA, L.G.A. ; SOMESSARI, E.S.R. ; VAZ, J.M. ; SPINACE, E.V. . AuCu/TiO2 catalysts prepared using electron beam irradiation for the preferential oxidation of carbon monoxide in hydrogen-rich mixtures. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-16, 2021. DOI: 10.15392/bjrs.v9i1A.1497

    Abstract: The major part of the world production of hydrogen (H2) is originated from a combination of methane steam reforming and water gas shift reaction resulting in an H2 rich mixture known as reformate gas, which contains about 1% vol (10,000 ppm) of carbon monoxide (CO). The preferential oxidation reaction of CO in H2 rich mixtures (CO PROX) has been considered a very promising process for H2 purification, reducing CO for values below 50 ppm allowing its use in PEMFC Fuel Cells. Au nanoparticles supported on TiO2 (Au/TiO2) catalysts have been shown good activity and selectivity for CO PROX reaction in the temperature range between 20 80 ºC; however, the catalytic activity strongly depends on the preparation method. Also, the addition of Cu to the Au/TiO2 catalyst could increase the activity and selectivity for CO PROX reaction. In this work, AuCu/TiO2 catalysts with composition 0.5%Au0.5%Cu/TiO2 were prepared in a single step using electron beam irradiation, where the Au3+ and Cu2+ ions were dissolved in water/2 propanol solution, the TiO2 support was dispersed and the obtained mixture was irradiated under stirring at room temperature using different dose rates (8 64 kGy s 1) and total doses (144 576 kGy). The catalysts were characterized by energy dispersive X ray analysis, X ray diffraction transmission electron microscopy, temperature programmed reduction and tested for CO PROX reaction. The best result was obtained with a catalyst prepared with a dose rate of 64 kGy s 1 and a total dose of 576 kGy showed a CO conversion of 45% and a CO2 selectivity of 30% at 150 ºC.

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  • IPEN-DOC 27898

    CORREA, J.C. ; CAVALLARO, F.A.; GARCIA, R.H.L. ; SANTOS, R.S.; AMADEU, R.A. ; BERNARDES, T.L.C. ; VELO, A.F. ; MESQUITA, C.H. ; HAMADA, M.M. . Chemical and physical analysis of sandstone rock from Botucatu Formation. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-19, 2021. DOI: 10.15392/bjrs.v9i1A.1479

    Abstract: The productive capacity of the Guarani aquifer System is subject to variations along its length, due to its complex structural and compositional heterogeneity. Several parameters may influence the quality of this reservoir rock, such as its mineralogical and textural constitution, as well as the physicochemical processes, since its diagenesis is not the same throughout the aquifer, influencing the water productivity in wells in different locations. Such parameters are useful in the geoscience studies for the elaboration of diagenetic models for the prediction of the reservoir quality. In this work, several properties of the sandstone rock from Botucatu Formation were determined using different techniques, such as geotechnical tests, optical microscopy (MO), electron scanning microscopy (SEM), X-ray Fluorescence and X-ray diffraction. The results indicate that the studied sandstones have characteristics of the reservoir rocks, with potential for water storage.

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  • IPEN-DOC 27897

    PEREIRA, M.C.C. ; FILHO, T.M. ; TOMAZ, L.F. ; BERRETTA, J.R. . Growth and optical characteristics of the CsI:Li scintillator crystal for use as radiation detector. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-18, 2021. DOI: 10.15392/bjrs.v9i1A.1478

    Abstract: Materials capable of converting ionizing radiation into light photons are called scintillators, some have specific efficiencies for certain applications and types of radiation, e.g. gamma, X-ray, alpha, beta and neutrons. CsI:Tl and NaI:Tl crystals are commonly found in the market because they have several applications, but few studies have been done on lithium doped cesium iodide crystal (CsI:Li). The lithium element, in this crystal used as a dopant, is also exploited as a converter for neutron detection, as it has a shock section of 940 barns for thermal neutrons. The study of the CsI:Li crystal is convenient considering the natural abundance of the lithium element with 7.5%, besides the interest in having a low cost national scintillator material, with an opportunity to search for the response of a detector for different types of radiation. The CsI:Li crystal was grown with molar concentration 10-4 to 10-1, using the vertical Bridgman technique. The parameters involved in the growth process were investigated. The transmittance was evaluated in the spectral region from 190 nm to 1100 nm. Luminescence emission spectra for the CsI:Li crystal were evaluated by photometric analysis of the crystal stimulated with a 137Cs (662 keV) source in front of the coupled sample at the monochromator input. The crystals showed maximum luminescence intensity at the wavelength of 420 nm. It was evaluated the response of the scintillators, when excited with gamma radiation of 241Am, 133Ba, 22Na, 137Cs, 60Co and neutron radiation from the AmBe source, with energy range of 1 MeV to 12 Mev.

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  • IPEN-DOC 27896

    SILVA, TATIANE B. de S.C. da ; OLIVEIRA, CINTIA C. de ; MARQUES, JOYCE R. ; FAUSTINO, MAINARA G. ; STELLATO, THAMIRIS B. ; MONTEIRO, LUCILENA R. ; PIRES, MARIA A.F. ; COTRIM, MARYCEL E.B. . Estimated pollutant load from Nuclear and Energy Research Institute (IPEN/CNEN-SP, Brazil). Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-14, 2021. DOI: 10.15392/bjrs.v9i1A.1468

    Abstract: The quantification of the pollutant load received by a water body is one necessary step to keep its original standards, irrespective of the releasing source. Thus, to monitor and control the content of pollutants released in a water body assures the water will remain free from excessive pollution. Also, no harm to human health and the environment will occur. Hence, this paper aims to estimate the pollutant load of sanitary wastewater released by the Nuclear and Energy Research Institute (IPEN / CNEN-SP) in 2015 and 2016. The analysis of Cd, Pb, Cu, Cr, Zn, Ba, Ni, Mn, Fe, B, and Sn was performed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). These metals and the total fixed solids were used to estimate the pollutant load. Wastewater flow measurement was carried out using bromide (Br-) as a tracer and with the values from IPEN`s annual water consumption. Since 2006, this is performed as part of the Environmental Monitoring Program (PMA-Q), in compliance with the current Brazilian Environmental Legislation and with the Term of Conduct Adjustment requirements, agreed with the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA). Even the pollutants load has increased in 2015 and 2016, the monitoring frequency and water consumption have diminished in the last years. These facts increase the uncertainties in the monitoring and could lead to non-compliances with the monitoring laws.

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  • IPEN-DOC 27895

    BERNARDES, T.L.S. ; AMADEU, R.A. ; SANTOS, R.S.; GARCIA, R.H.L. ; VELO, A.F. ; CAVALLARO, F.A.; MESQUITA, C.H. ; HAMADA, M.M. . Petrological study of the Iraty Formation Shale Rocks from Paraná Basin, Limeira, São Paulo. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-17, 2021. DOI: 10.15392/bjrs.v9i1A.1467

    Abstract: Shales are fine-grained rocks formed by clays and silt-sized particles in thin, relatively impermeable layers. They are originated from rocks that suffered weathering and erosion and their composition is quite variable. When oil production declines, interest arises to improve the understanding of the physicochemical properties of unconventional rocks, like shale. For the characterization of the shale samples of the Iraty Formation, the gamma-ray computed industrial tomography technique has been proposed to be used as an alternative to obtaining information about each element present in the mineral, the pore distribution, through the shale morphology. The tomographic results were compared with those obtained by conventional methodologies used in the petrological analysis, such as scanning electron microscopy (SEM), x-ray fluorescence, and x-ray diffraction.

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  • IPEN-DOC 27894

    LIMA, L.M.P.R.; KODAMA, Y. ; OTUBO, L. ; SANTOS, P.S. ; VASQUEZ, P.A. . Effect of ionizing radiation on the color of botanical collections - exsiccata. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-16, 2021. DOI: 10.15392/bjrs.v9i1A.1462

    Abstract: Conservation and preservation strategies are essential to manage botanical collections specially for dried herbarium specimens also known as exsiccates, usually referring to a set of identified specimens belonging to taxa and distributed among all herbaria around the world. Particularly, these collections are very sensitive to the attack of fungi and insects. In recent years, disinfection by ionizing radiation has become an effective strategy to preserve cultural heritage objects and archived materials with excellent results. In this work, the effects on color properties of gamma radiation on exsiccates samples were studied. Thus, two exsiccates, botanical pressed and dehydrated samples were selected from the Dom Bento José Pickel Herbarium (SPSF), situated at São Paulo (Brazil). These samples comes from Asteraceae and Solanaceae families and were collected in 1946 and 1984. The irradiation was performed at the Multipurpose Gamma Irradiation Facility at IPEN applying absorbed doses of 1 kGy, 6 kGy and 10 kGy, which are values of absorbed dose for disinfestation and disinfection. Results were analyzed using colorimetry with CIELAB color space scale and scanning electron microscopy. The results showed that there were no significant changes on colorimetric morphological properties of the samples.

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  • IPEN-DOC 27893

    SILVA, T.T. ; BORRELY, S.I. . Use of ionizing radiation for the inhibition and removal of cyanotoxins in water: a brief review. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-18, 2021. DOI: 10.15392/bjrs.v9i1A.1457

    Abstract: Cyanobacteria are an ancient and diverse group of microorganisms, considered as important contributors to the formation of Earth's atmosphere and nitrogen fixation. However, the input of nutrients in water by anthropogenic activities frequently provides cyanobacteria blooms associated with toxic compounds. Secondary metabolites, also called cyanotoxins, are often harmful to wild and domestic life, including humans. The first part of this review focuses on cyanobacteria and their ability to produce a variety of toxins as well as describe the Brazilian guidelines on the evaluation and management of these toxins in water quality. Then, we present a review of recent literature on the use of ionizing radiation in terms of cyanobacteria cell removal, degree of degradation of cyanotoxins in water, and reaction kinetics. In view of the exposed results, the paper concludes that ionizing radiation is an efficient and economically viable alternative for the remediation of areas contaminated by cyanobacterial blooms and cyanotoxins, especially in reservoirs intended for water treatment and supply. In addition, some suggestions are provided for further studies on the use of this technology in the treatment of drinking water.

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  • IPEN-DOC 27892

    GONÇALVES, P.N. ; DAMATTO, S.R. ; LEONARDO, L. ; SOUZA, J.M. . Natural radionuclides in soil profiles and sediment cores from Jundiaí reservoir, state of São Paulo. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-18, 2021. DOI: 10.15392/bjrs.v9i1A.1453

    Abstract: The activity concentration of natural radionuclides in soils and sediments is dependent on many factors, such as the rock parental material, pedogenic and weathering processes, physical and chemical properties of the environment, anthropogenic sources, among other aspects. There are few studies about the levels of natural radionuclides in reservoirs in both, international and national, literature. The objective of this paper was to evaluate the activity concentrations of 238U and 232Th by Instrumental Neutron Activation Analysis and 226Ra, 210Pb, 228Ra, 228Th and 40K by gamma spectrometry in two soil profiles and three sediment cores collected in the catchment area of Jundiai reservoir, located in the state of São Paulo, Brazil. Principal component analysis was applied to verify the correlation of the activity concentrations of the natural radionuclides with physical and chemical properties of soil and sediment samples. The mean activity concentrations of the radionuclides in the soil profiles 1 and 2 were, respectively: 238U – 37(1) and 32(1) Bq.kg-1; 232Th – 91(1) and 60(1) Bq.kg-1; 226Ra – 66(1) and 51(1) Bq.kg-1; 210Pb – 35(1) and 37(1) Bq.kg-1; 228Ra – 34(1) and 27(1) Bq.kg-1; 228Th – 78(1) and 58(1) Bq.kg-1; 40K – 96(2) and 171(7) Bq.kg-1. For the three sediment cores analyzed, the average activities concentrations of the radionuclides were, respectively: 238U – 64(0.5), 47(0.1) and 44(0.2) Bq.kg-1; 232Th – 122(2), 100(1) and 64(1) Bq.kg-1; 226Ra – 74(2), 71(1) and 45(1) Bq.kg-1; 210Pb – 70(3), 56(2) and 55(2) Bq.kg-1; 228Ra – 53(1), 41(1) and 33(1) Bq.kg-1; 228Th – 100(2), 92(1) and 63(2); 40K – 316(5), 237(1) and 136(2) Bq.kg-1.

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  • IPEN-DOC 27891

    FRANCO, J.G. ; SILVA, R.M.G. da; SUGUIMOTO, R.Y.; FRANCO, S.S.H.; VILLAVICENCIO, A.L.C.H.; ARTHUR, V. . Glycine max oil physical-chemical quality obtained of irradiated seeds. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-11, 2021. DOI: 10.15392/bjrs.v9i1A.1450

    Abstract: Ionizing radiation applied to agriculture has mainly benefited food production, as it reduces natural losses caused by physiological processes, as well as eliminating or reducing microorganisms, parasites and pests. In addition, this technique also allows the production of mutants with characteristics of greater productivity, precocity, smaller size, greater resistance to diseases and pests. These mutants are used to obtain new varieties of species of agronomic interest. The objective of this study was to evaluate the physic-chemical quality of the oil extracted from seeds of G. max (soybean) obtained from irradiated seeds with different doses of gamma radiation (0, 25, 50, 75 and 100 Gy of a Cobalt-60 source, type Gammacell-220 installed in CENA-USP). The physic-chemical analyzes included: AOCS Cd-3d-63, AOCS Cd-3-25 and AOCS Cd-1-25, Acids Index (I.A.), Saponification Index (I.S.), Iodide Index (I.I.), respectively. All analytical determinations were performed at least in triplicates. The values found for I.A., for I.S. and for I.I., did not differ from the oil sample obtained from soybean seeds from control subjects (without irradiation) regardless of the concentration and dose of radiation applied to the seeds. The oil analyzed did not show physical-chemical variation in comparison with the oil obtained from non-irradiated seeds, thus suggesting the absence of modifications in these parameters after the genetic improvement induced by the radiation.

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  • IPEN-DOC 27890

    FRANCO, S.S.H.; FRANCO, J.G. ; FERRARI, L.; LEANDRO, R.S.R. ; ARTHUR, P.B. ; ARTHUR, V. . Propagation of mango seedlings of the cultivar "Tommy" by grafts irradiated. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-8, 2021. DOI: 10.15392/bjrs.v9i1A.1449

    Abstract: Due to difficulties of vegetative propagating of any pants, many tests were performed with ionizing radiation aiming the modification of the characteristics of the plants for obtaining of the improved genotypes and of smaller size. Rootstock “Espada” cultivar, were used to obtain mango seedlings of “Tommy” cultivar. The cuttings were irradiated with different gamma radiation doses: 0 (control), 2.5, 5.0, 7.5 and 10.0 Gy, a dose rate of 0.323 kGy/h, in a source of Cobalt-60 type Gammacell-220, installed in the Center for Nuclear Energy in Agriculture, CENA-USP. After irradiation, was performed the grafting type cleft graft. It was made the first evaluation of height of the plants from the budding grafting after 24 months. Data were subjected by statistic program (SAS) and the means were compared by Tukey test (p <0.05). From the results obtained can be concluded that the doses of 2.5 Gy stimulated growth of the plants and the lethal dose was 10.0 Gy because don’t have development of plants.

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  • IPEN-DOC 27889

    ARTHUR, P.B. ; VILLAVICENCIO, A.L.C.H. ; HARDER, M.N.C. ; MACHI, A.R. ; LEANDRO, R.S.R. ; ARTHUR, V. . Sterilizing of Alphitobius diaperinus (Panzer, 1797) (Coleoptera: Tenebrionidae) irradiated in pupa stage. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-7, 2021. DOI: 10.15392/bjrs.v9i1A.1445

    Abstract: The use of irradiation process in stored grain may be the solution for the losses caused in these products by insects, as it does not induce resistance in the insects and leaves no toxic residue, and is considered an efficient and safe method of control of insects. The aim of the experiment was to determine the sterilizing dose of ionizing radiation from cobalt-60 to Alphitobius diaperinus (Panzer, 1797) (Coleoptera: Tenebrionidae) in peanuts irradiated in pupa stage. The experiment was conducted in the laboratory of Radiobiology and Environment of the Center for Nuclear Energy in Agriculture - CENA / USP., Piracicaba, SP, Brazil. Peanuts samples infested with pupae of A. diaperinus were utilized in the experiment that consisted of 8 treatments with 5 repetitions. Each repetition consisted of 20 pupae a total of 100 individuals per treatment. Were irradiated with doses of 0 (control), 25, 50, 75, 100, 125, 150 and 175 Gy, in a source of cobalt-60, Gammacell-220 type, with a rate dose of 381Gy / h. The experiment was conducted in a controlled temperature of 25 ± 5 ° C and relative humidity of 70 ± 5%. After of irradiation process was evaluated of the number of emerged adult insects in each repetition in the treatments. The results showed that the sterilizing dose in F1 generation was 125 Gy and the pupa lethal dose 150 Gy. The dose of 150 Gy of gamma radiation can be used as phytosanitary treatment to control of immature stages of A. diaperinus infested peanuts.

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  • IPEN-DOC 27888

    ARTHUR, P.B. ; MACHI, A.R. ; LEANDRO, R.S.R. ; HARDER, L.N.C. ; HARDER, M.N.C.; ARTHUR, V. . Disinfestation of mangoes haden infested by Anastrepha fraterculus (Wied., 1830) (Diptera, Tephritidae) with gamma radiation. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-11, 2021. DOI: 10.15392/bjrs.v9i1A.1444

    Abstract: The objective of experiment was determinate the radiation dose for disinfestation to mango Mangifera indica cv. Haden, infested by Anastrepha fraterculus larvae. For realization of the experiment, were collected fruits in the field, which were taking to Entomology laboratory where there was an infestation by the flies in cages during 72 hours period. Waited for the development of the larvae 5 and 8 days to infestation, after the mangos were irradiated in a Cobalt-60 source with doses of: 0(control), 50, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1.100, 1.200 and 1.300 Gy. After the irradiation, the fruits were placed in climate chamber with 25 ±5°C of temperature and 70±5% of relative humidity. Waited the larvae exit to out of the fruit until the transformation in pupae and adult stage. By the results obtained we can concluded that the lethal dose to larvae in mangoes infested with 5 and 8 days were 600 Gy and 1.000 Gy (0.6 and 1 kGy) respectively. The dose of 50 Gy prevented the total adult emergence for both treatments.

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  • IPEN-DOC 27887

    PRIMO, C.O. ; ANGELOCCI, L.V. ; KARAM JUNIOR, D.; ZEITUNI, C.A. ; ROSTELATO, M.E.C.M. . Dose-rate constant and air-kerma strength evaluation of a new 125I brachytherapy source using Monte-Carlo. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-11, 2021. DOI: 10.15392/bjrs.v9i1A.1441

    Abstract: Brachytherapy is a modality of radiotherapy which treats tumors using ionizing radiation with sources located close to the tumor. The sources can be produced from several radionuclides in various formats, such as Iodine-125 seeds and Iridium-192 wires. In order to produce a new Iodine-125 seed in IPEN/CNEN and ensure its quality, it is essential to describe the seed dosimetry, so when applied in a treatment the lowest possible dose to neighboring healthy tissues can be reached. The report by the AAPM’s Task Group 43 U1 is a document that indicates the dosimetry procedures in brachytherapy based on physical and geometrical parameters. In this study, dose-rate constant and air-kerma strength parameters were simulated using the Monte Carlo radiation transport code MCNP4C. The air-kerma strength is obtained from an ideal modeled seed, since its actual value should be measured for seeds individually in a specialized lab with a Wide-Angle Free-Air Chamber (WAFAC). Dose-rate constant and air-kerma strength are parameters that depends on intrinsic characteristics of the source, i.e. geometry, radionuclide, encapsulation, and together they define the dose-rate to the reference point. Radial dose function describes the dose fall-off with distance from the source. This study presents the values found for these parameters with associated statistical uncertainty, and is part of a larger project that aims the full dosimetry of this new seed model, including experimental measures.

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  • IPEN-DOC 27886

    ALBANO, A.M.S. ; ARTHUR, V. . Application of gamma radiation in pea (Pisum sativum L.) in nature to inhibit sprouting and increase shelf life. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-20, 2021. DOI: 10.15392/bjrs.v9i1A.1439

    Abstract: The irradiation of fresh post-harvest foods has as main interests: inhibit sprouting, increase shelf life, reduce or delay damage caused by insects and diseases. This work is a preliminary study on the use of gamma radiation in fresh peas grains (Pisum sativum L.) in order to evaluate its effects on the inhibition of sprout and its increase in shelf life. The peas were submitted at irradiation process with four radiation doses: 0 (control), 0.15, 0.30 and 0.45 kGy, in a 60Co research irradiator, with a dose rate of 0.323 kGy/h. After irradiation the samples were stored at 8 °C, being evaluated at 1, 7, 14 and 21 days by analyzes of: visual aspect, weight loss, color, hardness, pH, total soluble solids, total titratable acidity, ratio SST/TTA, water content and ash. By the results it was observed that in all parameters analyzes with gamma radiation doses used did not affect significantly in the shelf life of grains. The 0.30 kGy dose increased the germination of the peas and the 0.45 kGy dose was not sufficient to inhibit the sprouting of the peas.

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  • IPEN-DOC 27885

    COSTA, A.F.; MUNITA, C.S. ; ZUSE, S.; KIPNIS, R.. Archaeometry and Archaeology: preliminary studies of the ceramics from archaeological sites of the upper Madeira river/Rondônia - Brazil. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-16, 2021. DOI: 10.15392/bjrs.v9i1A.1424

    Abstract: In southwest Amazonia, in the region of the Upper Madeira River, Rondônia, archaeological research has shown that communities with diverse cultures co-existed in the pre-colonial past (ca. 1,000 BP). Archaeological sites from this period located on river banks and islands consist of large extensions of ceramic deposits which reflect different daily activities and social positions that existed within these groups. The complexity of these societies is attested to by the diversity of both ceramic forms and iconography. In this work, 140 ceramic fragments from eight archaeological sites were studied by means of instrumental neutron activation analysis (INAA) to determine Na, K, La, Sm, Yb, Lu, U, Sc, Cr, Fe, Co, Zn, Rb, Cs, Ce, Eu, Hf, Ta and Th mass fractions, with the purpose of classifying and ordering artifacts which are related to one another in their chemical compositions. The analytical method used is adequate for this type of study because it is a semi-destructive technique with high sensitivity and precision that can determine chemical elements in trace and ultra-trace levels, essential for studying small variations in elemental concentrations. Multivariate statistical analyses were used to evaluate the dataset. Initially the mass fractions were normalized to compensate for the large difference in magnitude among elements determined in percentage and in trace level. Subsequently, the mass fraction data were interpreted through cluster analysis, discriminant analysis and a log-log scatterplot. The results showed the existence of four compositional groups, indicating different clay sources.

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  • IPEN-DOC 27884

    TESSARO, A.P.G. ; VICENTE, R. ; MARUMO, J.T. ; TEIXEIRA, A.C.S.C.; ARAUJO, L.G. . Preliminary studies on electron beam irradiation as a treatment method of radioactive oil sludge. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-16, 2021. DOI: 10.15392/bjrs.v9i1A.1416

    Abstract: Radiation-induced advanced oxidation processes have been proposed for the treatment of various types of wastes. However, electron beam technologies for the removal of recalcitrant compounds in petroleum wastes are still poorly understood. This work aims at evaluating the effects on the degradation of organic matter from oil sludge by electron beam irradiation. Characterization methods were employed to identify the chemical elements present in the waste. Radiometric analysis was performed to identify radionuclides and measure dose rates. Preliminary immobilization of the untreated waste with cement indicated resistance values very close to the minimum established in national regulation. To treat the waste, an electron beam accelerator, model Dynamitron II, with variable current up to 25 mA was employed and the irradiation doses ranged from 20 to 200 kGy. Solutions were prepared with an initial H2O2 concentration of 1.34 mol·L-1. The effects on the removal of total organic carbon are discussed.

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  • IPEN-DOC 27883

    MELO, G.R.; ZAHN, G.S. ; GENEZINI, F.A. ; MOREIRA, E.G. . Development of an environmental monitoring station for HPGe detectors. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-14, 2021. DOI: 10.15392/bjrs.v9i1A.1412

    Abstract: Neutron Activation Analysis (NAA) is a well-established nondestructive analytic technique where the gamma radiation emitted by an irradiated sample is analyzed using an HPGe detector. The Neutron Activation Laboratory (LAN) of IPEN-CNEN/SP has been performing NAA analyses for over 30 years, and has plans of implementing quality control protocols to their analyses. In this sense, the environmental monitoring of the laboratories where the detectors are used has been performed for many years, in a manual way with no more than 2 measurements per day. In this work, an automated monitoring station based on a microcontroller ArduinoUNO board has been developed which comprises four thermo hygrometer sensors for monitoring different parts of the environment, plus a thermocouple for monitoring the inside of the liquid nitrogen dewar. The results obtained allow for a discussion on the performance and adequacy of the sensors.

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  • IPEN-DOC 27882

    ZAHN, G.S. ; GENEZINI, F.A. ; SILVA, P.S.C. ; NORY, R.M. ; MOREIRA, E.G. ; SANTIAGO, P.S. . On the feasibility of producing Lu-177 in the IEA-R1 reactor via the direct route. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-11, 2021. DOI: 10.15392/bjrs.v9i1A.1411

    Abstract: Over the last years the 177Lu radioisotope has attracted great interest for the use in therapeutic and diagnostic procedures simultaneously, being what is now called a theranostic radioisotope, with outstanding results in prostate and neuroendocrine cancer. There are mainly two ways of producing this radioisotope, by direct neutron capture in a 176Lu target (the “direct route") or by irradiating a 176Yb sample, producing 177Yb that will then decay to 177Lu (also referred as the “indirect route”). In this work, the technical feasibility of producing 177Lu in the IEA-R1 nuclear research reactor via the direct route was assessed, and the specific activity that could be obtained was estimated both experimentally and theoretically.

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  • IPEN-DOC 27881

    ZAHN, G.S. ; GENEZINI, F.A. . Efficiency stability of HPGe detectors under distinct count rates. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-8, 2021. DOI: 10.15392/bjrs.v9i1A.1410

    Abstract: In this work the reproducibility of the efficiency of different HPGe detectors was analyzed under a series of different conditions. The detectors studied were plugged either to a regular analogical amplifier or to a digital signal processing (DSP) device, to evaluate the possible differences between either setup. Detectors were inspected by performing a long series of sequential measurements with standard calibration sources and comparing the standard deviation of the number of counts per second in each series to the uncertainty of the individual measurements. Detectors were also subjected to distinct count rates, to verify the possible experimental issues associated with this parameter. The results allow a discussion on the stability of the detectors’ efficiencies over a few days, the possible dependence with the count rate, and the estimation of the uncertainty related to the efficiency variation.

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  • IPEN-DOC 27880

    ENOKIHARA, C.T. ; SCHULTZ-GUTTLER, R.A.; RELA, P.R. . Comparative analysis of quartz treated with gamma radiation originated from the hydrothermal geodes of the Paraná Basin, with quartz generated in the hydrothermal veins of Serra do Espinhaço. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-14, 2021. DOI: 10.15392/bjrs.v9i1A.1393

    Abstract: In Brazil, hydrothermal quartz may be found in the geodes of the basaltic rocks of the Paraná Basin and in the vein systems of quartzites of the Serra do Espinhaço. The quartz of hydrothermal origin of the Paraná Basin contains a great amount of structurally bound water in the form of molecular water, silanol, hydroxyl and abundant growth defects that are responsible for the green color formed by irradiation. To register the influence of water in the formation of the green color in the quartz of the Paraná Basin, quartz samples from the following regions were analyzed: Artigas, located in the Paraná Basin, Curvelo and Brejinho located in Serra do Espinhaço. The quartz from Artigas, formed at low temperature, has high concentration of molecular water and silanol and a greater amount of Fe than Al. The quartz from Curvelo with Al, but, without water molecular and silanol was formed by intermediate temperature and the quartz from Brejinho has very little Al, Fe and a small silanol and molecular water content. To characterize these samples, ICP, NAA, and NIR-FTIR spectroscopic measurements have been taken together with water loss techniques. The analysis by FTIR spectrometry of Artigas quartz samples shows strong absorptions of H2O and Si-OH, respectively, near the regions of 5300 cm-1 and 4500 cm-1. This content of molecular water and silanol in hydrothermal quartz of Artigas is responsible for the formation of NBOHC defects that produce, by gamma radiation, the green color.

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  • IPEN-DOC 27879

    ISHIMARU, G. ; SANTOS, E.C. ; SAIKI, M. . Evaluation of the spatial variability of the elements in tree barks used as biomonitors of atmospheric pollution. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-13, 2021. DOI: 10.15392/bjrs.v9i1A.1386

    Abstract: Tree barks have proven to be a valuable source of information on air quality. Nowadays, studies with this biomonitor are constantly being developed. However, data of several factors that affect the accumulation of the pollutants in the barks, such as bark porosity, duration of the deposition on the bark and dispersion or variability of pollutants in a defined area, are scarce in the literature. The aim of this study was to evaluate the spatial variability of chemical elements concentrations accumulated on Sibipiruna (Cenostigna pluviosarum) barks in order to examine their aerial dispersion in two small urban areas of the Metropolitan Area of São Paulo. The neutron activation analysis (NAA) applied in the analyses consisted of irradiation the aliquots of the sample together the synthetic element standards at the IEA-R1 nuclear reactor. Concentrations of the As, Br, Ca, Co, Cr, Cs, Fe, K, La, Mn, Rb, Sb, Sc, V and Zn were determined in tree barks using short and long irradiations. Results obtained in the analyses of the tree bark samples indicated that the variability of element concentrations depends on the element, study area and numbers of trees. The variability of element concentrations in general was higher for elements presenting low concentrations. Quality control of the analytical results was evaluated by the analysis of INCT-MPH-2 Mixed Polish Herbs Certified Reference Material and these results presented good accuracy with values of standardized difference or |ζ score| ≤ 2, indicating that the procedure of NAA applied is suitable for the analyses.

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  • IPEN-DOC 27878

    TORRECILHA, J.K. ; MARRICHI, J.M.O.; SOUZA, E.A.P.; GOUVEA, P.F.M. ; ALVES, I.C. ; SANTOS, A. ; SILVA, P.S.C. . Radiological characterization of peloids obtained by maturation with Águas de Lindóia, Poços de Caldas and Peruíbe waters. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-14, 2021. DOI: 10.15392/bjrs.v9i1A.1385

    Abstract: One of the concerns about using mineral clay for therapy treatments is its radioactivity content due to natural radionuclides, normally, associated with the clays. This work proposes to characterize the natural radionuclides of the peloids obtained by the maturation process of mixing two different clays (gray and green) with different mineral medicinal waters from Águas de Lindóia (SP), Poços de Caldas (MG) and sea water from Peruíbe (SP). The gamma spectrometry showed that the gray and green bentonite peloids, all the activity concentrations of radionuclides are higher in gray ones, except 40K. The activity concentration varied from 84 to 156 Bq kg−1 (228Ra), 25 to 156 Bq kg−1 (228Th), 9 to 161 Bq kg−1 (226Ra), 39 to 256 Bq kg−1 (210Pb) and 162 to 1070 Bq kg−1 (40K). However, by calculating the absorbed dose rate in the worst scenario, this may not be a problem for topical application. Although the waters from Águas de Lindóia and Poços de Caldas are considered radioactive they have not caused a significant increase in radionuclide concentrations absorbed dose rate.

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  • IPEN-DOC 27877

    FERREIRA, D.C.; DEL MASTRO, N.L. . An analysis of the support and quality of live after the diagnosis and treatment of prostate cancer in the radiotherapy sector. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-18, 2021. DOI: 10.15392/bjrs.v9i1A.1384

    Abstract: Prostate cancer is the most common chronic disease among men in most parts of the world. According to the National Cancer Institute (INCA) in Brazil in 2018, 68,000 new cases were registered. Among the main treatments the radiotherapy has been shown to be effective in controlling and curing the disease. However, it is noted that the patient satisfaction index is not the most encouraging and there is little research that points to the support of the hospital team. The aim of this study was to collect data from medical records about the adverse effect of the disease and through questionnaire the level of knowledge about the disease and the support offered by sector and to make recommendations for radiotherapy units Data were collected from 147 patients and of that total, 51 answered the questionnaire. The survey also shows that there was little referral to the complementary therapeutic service during of treatment. It is identified that more than 50% them knew very little about prostate cancer and 42% had no participation in the choice of treatment. It is observed that it is difficult to insert support policies for patients with prostate cancer, the professionals who work in oncology and radiotherapy centers underestimate the effects of the disease. It is observed, through research, that many of the symptoms and debilitations could be mitigated if there was a greater interaction between the health team and the patient, reducing the effects of radiation and accelerating the patient's integration for the social environment.

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  • IPEN-DOC 27876

    HARDER, M.N.C. ; ANDRADE, T.; REIS, F.M.; FEITOSA, N.M.; PEREIRA, P.; ROBERTO, S.P.; NEME-OYAN, F.F.; HARDER, L.N.C.; OLIVEIRA, S.R. ; ARTHUR, V. . Shelf-life of papaya nectar submitted to ionizing radiation. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-9, 2021. DOI: 10.15392/bjrs.v9i1A.1374

    Abstract: A kind of drink consumption that has grown and appreciated for the most people is the nectar. The papaya nectar was recognized as a differentiated form of this fruit, with which the industry also gains in time of conservation, since the papaya is an extremely perishable fruit. The aim of this study was to evaluate gamma radiation as a way of conserving papaya nectar. The nectar was developed and subjected to gamma radiation at the dose of 1 kGy in a dose tax of 0.356 kGy.hour-1 and compared this treatment with the control group (0 kGy). According to the results obtained, it can be concluded that the dose used was adequate for the conservation of this product for the period evaluated reaching the aim.

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  • IPEN-DOC 27875

    HARDER, M.N.C. ; BREVIGLIERI, E.; OLIVEIRA, B.B.; ZAMBONI, K.; CARVALHO, S.; NEME-OYAN, F.F.; HARDER, L.N.C.; OLIVEIRA, S.R. ; ARTHUR, V. . Apple porridge submitted to gamma radiation for shelf-life extended. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-11, 2021. DOI: 10.15392/bjrs.v9i1A.1372

    Abstract: Among many apple products, apple porridge is a popular product nowadays. It is a practical, healthy and tasty product that can be consumed throughout the day. However, it is an extremely perishable product. Therefore, the aim of this work was to evaluate the shelf-life period of apple porridge after the application of gamma radiation as a conservation technology. After the formulation of apple porridge was developed, which was subjected to gamma radiation at the dose of 1kGy in a dose tax of 0.356 kGy.hour-1 and compared this treatment with the control group (0kGy). From the results presented, it can be concluded that the conservation period of apple porridge submitted to gamma radiation is 60 days. From the 90th day, the samples showed microbial growth, becoming not accepted for consumption. In comparison to the control group, the use of gamma radiation was promising, since the standard sample showed contamination before 30 days. By the results it can be concluded that the dose used was adequate for the conservation of this product for the period evaluated.

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  • IPEN-DOC 27874

    DELGADO VIEIRA, A.C.; KODAMA, Y. ; OTUBO, L. ; SANTOS, P.S. ; VASQUEZ SALVADOR, P.A. . Effect of ionizing radiation on the color of featherwork. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-18, 2021. DOI: 10.15392/bjrs.v9i1A.1367

    Abstract: Featherwork collections are usually stored and managed by ethnographic museums. Even though the featherwork manufacturing is still practiced by the indigenous communities, the offer of raw material and the contact with the surrounding society ended up reducing the production scale of such objects. Consequently, the preservation of the material culture is very important, particularly in museums. Biodegradation can affect featherworks mainly by xylophagous insects and moths’ action. The tropical Brazilian weather contributes to the contamination and proliferation of insects and fungi making the preservation conditions difficult. The use of gamma radiation for the disinfection of cultural heritage objects has shown to be a safe process and an excellent alternative to traditional methods usually involving toxic chemical pesticides. In this work are presented the preliminary results of the ionizing radiation effects on the color and morphological properties of a featherwork from the Museum of Archeology and Ethnology of the University of São Paulo (MAE/USP). Samples of feathers were selected from the artifact and irradiated with gamma rays at the Multipurpose Gamma Irradiation Facility at IPEN, applying absorbed doses between 0.5 kGy to 200 kGy. The results shown had no significant changes on color and morphological properties within the disinfection absorbed dose range applied.

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  • IPEN-DOC 27873

    ALBUQUERQUE, C.R. ; MAIHARA, V.A. ; SILVA, P.S.C. . Iodine determination in edible algae species using epithermal neutron activation analysis methodology. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-11, 2021. DOI: 10.15392/bjrs.v9i1A.1365

    Abstract: Iodine is one of the essential trace elements of much interest in nutritional research being responsible for the production of the thyroid hormones, which has great importance for human metabolism. Edible algae species accumulate iodine from seawater and are considered a good dietary source of this nutrient. The Epithermal Neutron Activation Analysis (ENAA) was applied to determine the iodine concentration in edible algae species and derivatives. Twenty-one samples for 4 edible algae species Porphyra umbilicalis (common name: Nori), Hijikia fusiforme (Hijiki), Undaria pinnatifida (Wakame) and Laminaria spp. (Kombu) and 3 samples of the derivative sample, ágar, were analyzed. The results pointed out a great variability of I concentration in these species. The highest I concentration obtained was 9324±113 mg/kg in Laminaria spp. (Kombu). Hijikia fulsiforme (Hijiki) also presented high values (1803±86 mg/kg). The lowest I content was obtained in agar samples (3.18±0.29 mg/kg). All analyzed algae samples exceed the recommended value (150 μg/day) and an ingestion of 1 g/day of Laminaria spp. (Kombu) exceed the maximum tolerable limit (1100 μg/day) and its consumption must be controlled to avoid possible health problems.

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  • IPEN-DOC 27872

    CORTEZ, B. ; CHUBACI, J.F.D.; GOMES, M.B. ; MENDES, L. ; ROCCA, R.R.; ARIZACA, E.C.E.; WATANABE, S.. EPR dating of sediments in the region of Iguape - Cananéia, Brazil. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-13, 2021. DOI: 10.15392/bjrs.v9i1A.1364

    Abstract: Dating of sediments was performed by physics method in this work. Natural radioactivity is present in sediments, and this method is based on the measurement of energy of radiation stored in the solid. Gamma irradiation of sediments create deffects in quartz structure that stores energy by the absorption of radiation. In the present work, Icapara sediment dating was done by Electron Paramagnetic Resonance (EPR) spectroscopy method. The intensity of EPR signal corresponding to the number of lattice defects with an unpaired electron in sediment quartz could be measured to estimate the accumulated dose of natural radiation and to calculate the geologic age. Located in the region of Iguape at southeast coast of São Paulo State, Icapara is a large sand terrace that was formed due to sea level fluctation that occurred more than 130 thousand years ago. Samples were taken from a point about 9 - 10 meters above the current control of the sea. Ages of 38,000 ±12,000 and 46,000 ± 7,000 years were obtained in this study by EPR analysis that are correlated with the Quaternary Period.

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  • IPEN-DOC 27871

    NAGAI, M.L.E. ; SANTOS, P.S. ; VASQUEZ, P.A.S. . Irradiation protocol for cultural heritage conservation treatment. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-16, 2021. DOI: 10.15392/bjrs.v9i1A.1351

    Abstract: Ionizing radiation supplied by cobalt-60 is an excellent alternative tool to the traditional process of decontamination of cultural and historical materials, mainly because of its biocidal action. Analyzing the occurrence of requests for treatment materials from cultural institutions with ionizing radiation for fungal decontamination in the Multipurpose Gamma Irradiation Facility of the Nuclear and Energy Research Institute - CTR/IPEN, there was a need to establish a protocol for the care of institutions and individuals carrying cultural and historical collections. The study proposal was the establishment an efficient and reproducible model of an irradiation protocol for the treatment of cultural heritage materials in industrial irradiators, respecting the ethical principles of conservation and restoration activities. The objective of the protocol is to be a practical guide, from the detection of the problem to the final cleaning, so that conservator-restorers and professionals of the irradiation can act in a collaborative and objective way to reach the objective of the treatment.

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  • IPEN-DOC 27870

    CARVALHO, D.V.S. ; GREGIANIN, G.M.; MESQUITA, C.H. . Development of an automated source holder in IoT for application in industrial process tomography. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-11, 2021. DOI: 10.15392/bjrs.v9i1A.1349

    Abstract: Computed tomography technology uses an electromagnetic radiation source or particulate radiation source, to analyze / study different samples that can range from living organisms to the most diverse objects (rocks, phantoms, etc.). The use of the radioactive materials may cause harm to the operator if he is exposed to the source of radiation, so aiming at the safety of the operator, the objective of this work is to develop an Internet of Things automation system for the opening of the Industrial Process Tomography source holder for industrial tomography applications. Thus, this system can drive the stepper motors through this platform can be opened at a safe distance to the operator, avoiding the operator to take radiation dose to perform this operation. For the IPT project, five source holders were made so that each was positioned diametrically opposite each array of detectors. In this project we used 192Ir sources that have activity of 18,500 MBq and that were produced in the reactor IEA-R1, from the neutron bombardment of the pellet containing stable isotope 191Ir. The main characteristics of 192Ir are: half-life of 74.2 days; radiation energy from 0.13 to 0.65 MeV. For the safety of the operator during the opening of the sources, an automated opening system with IoT that can be activated with software installed on the tomography or by a smartphone application by the MQTT protocol, which makes it possible to be monitored in real time at long distance showing the opening and closing status of each source holder.

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  • IPEN-DOC 27869

    SANTOS, W.S.; NEVES, L.P.; PERINI, A.P.; SANTOS, C.J.; BELINATO, W.; CALDAS, L.V.E. . The influence of the lead eyewear geometry on the doses to the eye lens. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-9, 2021. DOI: 10.15392/bjrs.v9i1A.1347

    Abstract: The scattered radiation from interventional procedures is an important source of radiological risk for the medical staff. Considering all affected organs, the eye lens is among the most critical organs. As pointed out by several studies, even for low radiation doses, the appearance of cataract may occur. Considering this scenario, the radiation doses to the eye lens were determined using three different lead eyewear models commonly employed in the interventional radiology. The interventional radiologist was represented by an adult virtual anthropomorphic phantom (MASH3), coupled to the Monte Carlo code MCNP 6.1, in a typical cardiac interventional radiology procedure. The eyewear had a thickness 0.5 mmPb each, and the evaluation was carried out for four different beam angulations (PA, LAO90, LAO65 e RAO65), utilizing a tube voltage of 80 kVp, and HVL of 4 mmAl. The results pointed out that the shielding efficiency has a strong dependence on the eyewear type utilized, which may be very useful for the decision-making during the acquisition of such equipments.

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  • IPEN-DOC 27868

    CASTRO, M.C. ; SILVA, N.F. ; CALDAS, L.V.E. . Dosimetric tests of an extrapolation chamber in standard computed tomography beams. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-6, 2021. DOI: 10.15392/bjrs.v9i1A.1338

    Abstract: Computed tomography (CT) diagnostic exams are responsible for the highest dose values to the patients. There-fore, the radiation doses in this procedure must be accurate. For the dosimetry of CT beams, the radiation detec-tor is usually a pencil-type ionization chamber. This type of dosimeter presents a uniform response to the inci-dent radiation beam from all angles, which makes it suitable for such equipment since the X-ray tube executes a circular movement around the table during irradiation. However, there is no primary standard system for this kind of radiation beam yet. In order to search for a CT primary standard, an extrapolation chamber built at the Calibration Laboratory (LCI) of the Instituto de Pesquisas Energéticas e Nucleares (IPEN) was tested. An ex-trapolation chamber is a parallel-plate ionization chamber that allows the variation of its sensitive air volume. This chamber was used previously for low-energy radiation beams and showed results within the international recommended limits. The aim of this work is to perform some characterization tests (saturation curve, polarity effect, ion collection efficiency and linearity of response) considering the chamber depth of 1.25 mm in the radia-tion qualities for computed tomography beams at the LCI. The results showed to be within the international recommended limits.

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  • IPEN-DOC 27867

    BRAGUIN, L.N.M. ; SILVA, C.A.J. ; COSTA, I. ; SAIKI, M. . Neutron activation analysis of austenitic stainless steel used as biomaterial. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-16, 2021. DOI: 10.15392/bjrs.v9i1A.1337

    Abstract: Austenitic stainless steel alloys, mainly those produced according to ISO 5832-1, have received much attention due to their promising characteristics to be used as biomaterials. The aim of this study was to establish the proper conditions of neutron activation analysis (NAA) in order to determine chemical elements in a sample of ISO 5832-1 stainless steel. These determinations are of great interest for further evaluation of its corrosion resistance and of cytotoxicity of corrosion products. For the analyses, chips of ISO 5832-1 austenitic stainless steel were obtained. Aliquots of this material were weighed in polyethylene involucres and irradiated together with synthetic element standards at the IEA-R1 nuclear research reactor. Short and long irradiations were carried out using thermal neutron flux of about 4.5 x 1012 n cm-2 s-1. Quality control of the results was performed by analyzing two certified reference materials (CRMs). The elements concentrations of Cr, Cu, Mn, Mo and Ni obtained in the ISO 5832-1 austenitic alloy are within the specification values of this material. Besides, the elements As, Co, V and W were determined in this alloy. The sensitivity of the technique was verified by the determination of detection and quantification limits. In the case of CRMs, their results presented precision and accuracy for most of elements with relative standard deviations and relative errors lower than 15 %. Results obtained in this study demonstrated the viability of applying NAA in the analysis of the ISO 5832-1 stainless steel alloy.

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  • IPEN-DOC 27866

    REIS, D.P. ; MOREIRA, E.G. . Determination of toxic elements in fish of the genus 17 consumed by artisanal fishermen of the District of Riacho Grande, São Bernardo do Campo city, Brazil. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-16, 2021. DOI: 10.15392/bjrs.v9i1A.1332

    Abstract: Toxic elements in contact with the human body cause numerous health problems. The contamination occurs mostly by food consumption, such as the ingestion of fish contaminated with high concentrati ons of As, Cd, Hg or Pb among other elements. Many fishermen and their family members end up exposing themselves to different toxic elements due to fish based diet as the main protein nutrient because they are unaware of the health risks associated with th e consumption of fish from contaminated waters. In the present study, quantification of the toxic or potentially toxic elements As, Br, Cs, Cr, Co, Fe, K, Na, Sc, Se and Zn in samples of fish of the genus Astyanax (known by the common name of lambari )). The fish was collected at Billings Reservoir by fishermen from the Riacho Grande District (São Bernardo do Campo city , São Paulo State, Brazil ) is presented. The lambari fish had great relevance in this study because it is consumed as a snack, in which the subject feeds on the whole organism of the fish, having a greater risk of direct contact with toxic elements through ingestion. Elements were determined by Instrumental Neutron Activation Analysis (INAA). This study is important in establishing an updated spatiotemporal vision of the contamination by various elements of interest in the region Additionally, it contributes to the food safety assurance, regarding inorganic contaminants referred by the Brazilian Health Regulatory Agency (ANVISA).

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  • IPEN-DOC 27865

    CHIERENTIN, G.S. ; TEIXEIRA, B.S. ; MASTRO, N.L. . Total phenolic compounds of irradiated chia seeds. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-9, 2021. DOI: 10.15392/bjrs.v9i1A.1331

    Abstract: Chia seeds (Salvia hispanica L.) is a good source of oil, protein, dietary fiber, minerals and polyphenolic compounds. In order to study the influence of the processing methods on the content of phenolic compounds, the objective of this work was to evaluate the effect of gamma radiation, doses 0 (control), 5, 10 and 20 kGy, on the total phenolic compounds extracted from chia seeds. Seeds were first defatted and extracts produced with proper solvents. Total phenolic content was determined according to Folin-Ciocalteu’s method and the extraction solvents applied were ethanol 100%, ethanol 70%, ethanol 50%, methanol 100%, methanol 70% and methanol 50%. When using ethanol 100%, ethanol 70 %, ethanol 50%, methanol 100% and methanol 70%, the extraction yield was independent of the absorbed dose. With methanol 50%, the irradiation process affected positively the total phenolic yield from of chia seeds. In general, the absorbed dose as well as the nature of the solvent affected the extraction yield, although in a limited manner.

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  • IPEN-DOC 27864

    GONCALVES, J.A.C. ; BUENO, C.C. ; MANGIAROTTI, A.. Comparative evaluation of the performance of thin diodes used as on-line dosimeters in radiation processing applications. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-8, 2021. DOI: 10.15392/bjrs.v9i1A.1327

    Abstract: In this work, we report a comparison between the performance of two samples of commercial PIN photodiodes (SFH206K from Osram® and S2506-04 from Hamamatsu®) mainly addressing the variation of their current sensitivities with accumulated dose ranging from 0-15 kGy. All the results so far obtained have revealed that the radiation induced currents are linearly dependent on dose rates from 3.65 to 55.64 Gy/h. The current sensitivity of both unirradiated diodes (0.178 nA.h/Gy.mm3) slightly decreases with accumulated dose, namely 0.32%/kGy (SFH206K) and 1.4%/kGy (S2506-04). Although the SFH206K device compares favorably with the S2506-04, both diodes can be considered as a low budge alternative, good enough for on-line dosimetry applications in the field of radiation processing.

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  • IPEN-DOC 27863

    NOGUEIRA, A.L. ; MUNITA, C.S. . The effect of data standardization in cluster analysis. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-15, 2021. DOI: 10.15392/bjrs.v9i1A.1324

    Abstract: The application of multivariate techniques to experimental results requires a responsibility on behalf of the researcher to understand, evaluate and interpret their results, especially the ones that are more complex. The objective of this article is to evaluate the impact of three standardization techniques on the formation of clusters by means of the Kohonen neural network were studied. The standardization techniques studied were logarithm (log), generalized-log and improved minimum-maximum. The studies were performed using two different databases consisting of 298, named B1, and 146 samples, named B2. The B1 dataset is formed by samples that form two cluster very close. However, the B2 dataset form three diferent and separated cluster. The mass fractions of As, Ce, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Sc, Sm, Tb, Th, U, and Yb of each sample were determined by instrumental neutron activation analysis, INAA. Three validation indices : Jaccard, Fowlkes-Mallows and Rand were performed on the dataset. The results suggest that when the cluster are close, the improved minimum-maximum satandardization is better than the logarithm and generalized-log. However, when the cluster are separated, the logarithm and generalized-log are better than the improved minimum-maximum technique.

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  • IPEN-DOC 27862

    BARROS, J.F. ; SILVA, R.P.; MUNITA, C.J.S. . Preliminary chemical studies at the Jericho archaeological site. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-12, 2021. DOI: 10.15392/bjrs.v9i1A.1319

    Abstract: This study measured the chemical composition of 45 ceramic samples from the Jericho archaeological site, Palestine, by means of instrumental neutron activation analysis (INAA). The mass fraction of Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Rb, Sc, Sm, Th, U, Yb and Zn was determined with the purpose to detect the presence of ceramic groupings based on their composition. The analytical method is appropriate for this type of study because it is a non-destructive technique with high sensitivity, accuracy and precision, and determines chemical elements in trace and ultra-trace levels. These characteristics are essential to study small concentration variations. Initially the mass fractions were normalized to compensate for the large difference in magnitude among elements determined in percentage and trace level. Subsequently, the dataset was interpreted through cluster and discriminant analysis. The results showed the existence of three different chemical groups.

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  • IPEN-DOC 27861

    TAPPIZ, BRUNO ; MOREIRA, EDSON G. . Expanded uncertainty assessment in fish samples analyzed by INAA and AAS. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-14, 2021. DOI: 10.15392/bjrs.v9i1A.1314

    Abstract: Measurement uncertainty was estimated following the EURACHEM guide (Quantifying Uncertainty in Analytical Measurement) for the elements As, Br, Cl, Co, Cr, Cs, Fe, K, Mg, Mn, Na, Rb, Sb, Se and Zn determined by In-strumental Neutron Activation Analysis (INAA) and for the elements Cd, Hg and Pb determined by Atomic Absorption Spectrometry (AAS) in the fillet of the most consumed fish species at São Paulo city, Brazil. INAA expanded uncertainties ranged from 1.0 to 21% and the main contributions were due the counting statistics of sample and pipetted standards. For AAS, expanded uncertainties ranged from 6.5 to 13% and the main contri-butions were associated to the calibration curves. Uncertainty results were compared with the standard devia-tions of the mass fraction in the fishes (n = 10). Due to the wide variability in the mass fraction in the analyzed fish tissues, explained by factors such gender, age, fat content and fishing location of the specimens of each spe-cies, standard deviations were greater than expanded uncertainties, which means that the natural variability of the elements determined is greater than the data dispersion associated with the analytical techniques. Hence the used techniques were adequate for the fish fillet samples analyses.

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  • IPEN-DOC 27860

    SMITH, R.B. ; ROMERO, F.; VICENTE, R. . Plutonium-238: the fuel crisis. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-11, 2021. DOI: 10.15392/bjrs.v9i1A.1312

    Abstract: Plutonium-238 is currently still the best fuel to power satellites to be sent to deep space in regions where the solar panels can no longer efficiently receive the sunlight. For 50 years, the National Aeronautics and Space Administration (NASA) has used this radioisotope as a fuel in radioisotope thermoelectric generators (RTGs) installed on satellites such as Pioneer 10 and 11, Voyager 1 and 2, Cassini-Huygens and New Horizons, as well as the various rovers sent to the Moon and to Mars, among others. Plutonium-238 is not a naturally occurring isotope on the planet, it was produced in greater quantity during the Cold War period as a by-product of the production of Plutonium-239 used for nuclear bombs. However, after the shutting down of the Savannah River reactors in 1988 and the ending of the Soviet Union in 1991, the United States stock of Plutonium-238 has been increasingly reduced, which threatens NASA's future space projects. This paper presents a brief bibliographic review about the subject, as well as commentaries on the options available to the United States, from restarting the production of this fuel, to possible alternatives for a new type of fuel or equipment that may supply the spacecrafts.

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  • IPEN-DOC 27859

    MELO, C.G. ; ROSA, J.M. ; GARCIA, V.S.G. ; BORRELY, S.I. ; PEREIRA, M.C.C. . Toxicity and color reduction of reactive dyestuff RB 21 and surfactant submitted to electron beam irradiation. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-14, 2021. DOI: 10.15392/bjrs.v9i1A.1311

    Abstract: There is an unwelcome reaction between the coloring and the water during the dyeing procedure, a portion of the coloring agent is lost in the bathing and it will compose the final whole effluent. The high absorbance index is related to lost dyestuffs and they also contribute with the toxic effects to the aquatic biota. In addition, these effluents contain large quantity of surfactants applied during dyeing baths, which also contribute to the high toxicity in these samples. The objective of this study was to evaluate electron beam irradiation technology, applied in samples of the Color Index Reactive Blue 21 (RB 21) dyestuff and in samples of surfactant non-ionic and in order to reduce toxicity for both and for RB 21, color reduction. Among the objectives of the study there are the dyestuff exhaustion degree, and some physical-chemical parameters. The acute toxicity assays were carried with Daphnia similis microcrustacean and the results of the dyestuff solution were: the irradiated samples with concentration 0.61 g L-1 did not present significant results, the EC 50 (%) value was to 58.26 for irradiated sample with 2.5 kGy and EC 50 (%) 63.59 for sample irradiated with 5 kGy. The surfactant was more toxic than RB 21, with EC 50 (%) value at 0.42. The color reduction reached 63.30% for the sample of the lowest concentration of effluent. There was a reduction of pH during irradiation.

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  • IPEN-DOC 27858

    SANTOS, E.C. ; MAIHARA, V.A. ; GENEZINI, F.A. ; SAIKI, M. . A study on tree bark samples for atmospheric pollution monitoring. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-17, 2021. DOI: 10.15392/bjrs.v9i1A.1293

    Abstract: Tree barks are considered a promising indicator of air pollution monitoring, because of its accumulation of aerosol particles, simplicity of species identification and wide geographical distribution. However, there are no established protocols for its sampling as well as there are no detailed studies on its usability as an alternative or complementary indicator of atmospheric pollution. In this study, barks from very common tree species, Sibipiruna (Poincianella pluviosa) and Tipuana (Tipuana tipu), were analyzed to define experimental conditions for their use as biomonitor of air pollution. Bark samples collected at the São Paulo city were cleaned and ground for analysis. Instrumental neutron activation analysis (INAA) was applied for the determination of As, Br, Ca, Co, Cr, Fe, K, Sb, Sc and Zn and graphite furnace atomic absorption spectrometry (GF AAS) for Cd and Pb. Results obtained in these analyses indicated that species of trees, bark surface layers taken for analysis as well as tree trunk diameter or tree age should be considered for use tree bark as a biomonitor. Analytical control of results carried out by analyzing certified reference materials demonstrated that INAA and GF AAS techniques can provide reliable data for element concentrations with standardized differences, |Enscore | < 1.

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  • IPEN-DOC 27857

    BAPTISTA, TATYANA S. ; FEHER, ANSELMO ; RODRIGUES, BRUNA T. ; ZEITUNI, CARLOS A. ; MOURA, JOÃO A. ; ROSTELATO, MARIA E.C.M. . A proposal of process validation in the implementation of Good Manufacturing Practices in brachytherapy sources production. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-8, 2021. DOI: 10.15392/bjrs.v9i1A.1285

    Abstract: New laboratories for brachytherapy sources production are being implemented in our facility at IPEN, in São Paulo. A great challenge implementing a production laboratory is to comply with the Good Manufacturing Practices (GMPs), which involves process validation and all supporting activities such as cleaning and sanitization. Much more than compliance with regulatory guidelines, required for certification and inspections, a validation builds large process knowledge, provides possibilities for optimization and improvement, increasing the degree of maturity of all people involved and the quality system. The process validation results in a document that certifies that any procedure, process, equipment, material, operation, or system leads to the expected results. This work focused on the new laboratory, been assembled to produce small iodine-125 seeds. The process validation was performed three times for evaluation. The parameters evaluated in this study were: the source welding efficiency and the leakage tests results (immersion test). The welding efficiency does not have an established parameter, since is visually evaluated by the operator, and the leakage detection must be under 5 nCi / 185 Bq, accordingly with the ISO 9978. We observed values were average 79-87% production efficiency and leakage tests were under 5 nCi/seed. Although established values for the global efficiency aren’t available in the literature, the results showed high consistency and acceptable percentages, especially when other similar manufacturing processes are used in comparison (average 85-70% found in the literature for other similar metallic structures). Those values will be important data when drafting the validation document and to follow the Good Manufacturing Practices (GMPs).

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  • IPEN-DOC 27856

    FRANCA, A.A.S. ; VICENTE, R. . Immobilization of liquid radioactive waste in cement. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-14, 2021. DOI: 10.15392/bjrs.v9i1A.1283

    Abstract: Immobilization of radioactive waste is required to comply with nuclear regulations and waste acceptance criteria in a repository, which require the waste to be solid or immobilized in solid form within a durable and resistant matrix [1-4]. Cement is the most frequently used material for the immobilization of liquid, low-level waste, since it has many advantages, such as the ease of preparation at room temperature and the low cost [5, 6]. In this paper, we describe the characteristics of cement-water mixtures, homogenized in a drum using a vibration table as the mixing device. Common Portland cement was used as the immobilization matrix. The homogeneity of the mixtures is evaluated using cement dye in appropriate amounts. Initially, the distribution of the mineral dye was made by visual inspection. The batches were carried out with three different ways of feeding the components. Different results were obtained depending on the feeding methods employed.

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  • IPEN-DOC 27855

    BARBOSA, I.T.F.; SEO, E.S.M. ; SILVA, L.G.A. ; MIRANDA, L.F.. Hydrogels applied in cosmetology irradiated by ionizing radiation. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-15, 2021. DOI: 10.15392/bjrs.v9i1A.1278

    Abstract: Hydrogels are three-dimensionally crosslinked polymers that exhibit high capacity to absorb water or solvents, without compromising its structure, allowing its application in cosmetic products, because it presents easy scattering and vehicular active principles. The use of ionizing radiation to obtain the hydrogels provides the absence of chemical initiators; sterilization; reticulation and adjustment of physical-chemical properties. In this work different types of hydrogels containing 5 wt%, 7.5 wt% and 10 wt% PVP concentrations and different radiation 25 and 20 kGy doses were prepared, maintaining 3 wt% PEG concentrations and 1 wt% agar, based on literature studies. The samples were characterized by dehydration as a function of time, acidity, visual and sensorial analyzes and stability. The results obtained showed that all the compositions are stable, have a pH close to the skin and the compositions containing 5 wt% PVP, obtained with 20 and 25 kGy radiation dose, undergo greater dehydration. In sensory research, the hydrogels containing 7.5 wt% PVP, obtained with 25 kGy radiation dose, presented the best results in terms of absorption, sliding, odor, while the composition containing 10 wt% PVP, obtained with 25 kGy radiation dose, proved to be inadequate in the public perception. Therefore, the hydrogels obtained with 7.5 wt% PVP, with 25 kGy radiation dose, were the most suitable for applications in cosmetic products.

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  • IPEN-DOC 27854

    SOUZA, C.D. de ; ZEITUNI, C.A. ; ARCOS ROSERO, W.A. ; NOGUEIRA, B.R. ; ROSTELATO, M.E.C.M. . New gold-198 nanoparticle synthesis to be used in cancer treatment. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-18, 2021. DOI: 10.15392/bjrs.v9i1A.1260

    Abstract: Gold nanoparticles (NPs) have been intriguing scientists for over 100 years. Recently, they have been studied for new applications such as cancer treatment. Although the synthesis of gold nanoparticles is extensively reported, in the majority of cases the methodology is confused and/or not clear. We describe a new synthesis methodology for radioactive gold‐198 NPs. Gold-198 was activated in IPEN IEA-01 nuclear reactor. After that, chloroauric acid (HAuCl4) was formed by dissolving the radioactive gold with aqua regia and performing repeated heating cycles. 0.1 mM HAuCl4 containing 100 μL of 1 M NaOH was prepared in a flask equipped with a reflux condenser. The solution was brought to boil and stirred with a PTFE‐coated magnetic stir‐bar. Then 5 mL of sodium citrate was rapidly added. The reaction turns from light yellow to clear, black, dark purple until the solution attained a wine‐red color (2–3 min). Dynamic light scattering (DLS) confirmed 8 nm particles. The presence of gold‐198 (197.968 g/mol; half‐life: 2.69517; decay mode: β‐; average energy: 1.3723 MeV) was confirmed by an ORTEC HPGe detector. DLS was performed after complete decay confirming the 8 nm diameter maintenance. TEM analysis of the same solution yielded particles with 11 nm. We were able to achieve radioactive gold‐198 NPs and are performing further studies such as: coating reactions, in‐vitro and in‐vivo studies.

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  • IPEN-DOC 27853

    OTERO, A.G.L. ; POTIENS JUNIOR, A.J. ; MARUMO, J.T. . Comparing deep learning architectures on gamma-spectroscopy analysis for nuclear waste characterization. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-8, 2021. DOI: 10.15392/bjrs.v9i1A.1257

    Abstract: Neural networks, particularly deep neural networks, are used nowadays with great success in several tasks, such as image classification, image segmentation, translation, text to speech, speech to text, achieving super-human performance. In this study, the capabilities of deep learning are explored on a new field: gamma-spectroscopy analysis, comparing the classification performance of different deep neural network architectures. The following architectures where tested: VGG-16, VGG-19, Xception, ResNet, InceptionV3, and MobileNet, which are available through the Keras Deep Learning framework to identify several different radionuclides (Am-241, Ba133, Cd-109, Co-60, Cs-137, Eu-152, Mn-54, Na-24, and Pb-210). Using an HPGe detector to acquire several gamma spectra from different sealed sources to create a dataset used for the training and validation of the neural network's comparison. This study demonstrates the strengths and weaknesses of applying deep learning on gamma-spectroscopy analysis for nuclear waste characterization.

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  • IPEN-DOC 27852

    AQUINO, S. ; LIMA, J.E.A.; BORRELY, S.I. . Bioburden proliferation in vehicle air filters waste: the use of gamma radiation on fungal decontamination. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-14, 2021. DOI: 10.15392/bjrs.v9i1A.1254

    Abstract: This study aimed to analyze the fungal contamination of air-conditioning filters waste (n=20) as an indicator of Quality Air Indoor from different car models, that were collected from 10 exchange stations located in the South, North, West, Downtown and East, of the city of São Paulo in São Paulo State, Brazil, during the period from October 2017 to November 2018. Sampling of filter particles (33 fragments of 10 × 10-mm size) were plated onto solidified Potato Dextrose agar in Petri dishes. The samples were incubated for 7 days at 25 °C and were stored in a standard Biochemical Oxygen Demand incubator, for growth of fungal cultures. After incubation, the fungal culture in the plates was evaluated, and the total counting of infected fragments was expressed as a percentage. The fungi were examined by Lactophenol blue solution staining for microscopy. All samples were contaminated with various fungal genera, including Aspergillus, Alternaria, Cladosporium, and Penicillium. The study also aimed to evaluate the fungal enumeration in the samples that were irradiated with dose of 10 kGy to fungal decontamination of air-conditioning filters waste. Of total samples, 50% were completed decontaminated, but some genera such as Aspergillus, Penicillium, Rhizopus, Cladosporium and yeasts demonstrated radioresistance at the dose of 10 kGy. The only yeast called Rhodotorula showed an increase in growth after the irradiation process.

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  • IPEN-DOC 27851

    GUILHEN, S.N. ; SOUZA, A.L.; COTRIM, M.E.B. ; PIRES, M.A.F. . Direct determination of aluminum in low-enriched UAlx targets (UAlx-Al) by ICP OES. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-18, 2021. DOI: 10.15392/bjrs.v9i1A.1247

    Abstract: The production of molybdenum-99 (99Mo) using low-enriched uranium targets (< 20% 235U) dispersed in aluminum (UAlx) is a very promising strategy towards the independence in 99Mo local production. A thorough control must be performed to ensure that these targets meet the regulatory requirements to achieve the expected efficiency in the reactor. The determination of the targets’ composition is of high interest, because the distribution of Al in different phases may have an impact on the U concentration. Among the techniques used for this purpose, inductively coupled plasma optical emission spectrometry (ICP OES) stands out because of its high sensitivity and precision, allowing for simultaneous determination of several elements in a variety of samples and matrices. However, because U exhibits a complex emission spectrum, spectral interferences are prone to affect the analysis of Al, calling for time consuming preparation steps to remove the U from the matrix. This study proposes a method of direct determination of Al in UAlx targets through the selection of specific emission lines enabled by the evaluation of the associated interferences on the recovery values.

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  • IPEN-DOC 27850

    FERREIRA, A.O.; PECEQUILO, B.R.S. . Dose rates evaluation of some granitic rocks from the Paraná state. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-11, 2021. DOI: 10.15392/bjrs.v9i1A.1242

    Abstract: Granitic rocks, widely used as building materials, are known to contain natural radionuclides and can be an important source of radiation for the population. Thirty-four samples of granite rocks from geological occurrences in Paraná state were measured with detector for evaluation of 226Ra, 232Th and 40K activity concentrations. The effective annual external dose was evaluated from these radionuclides activities using a dosimetric room model with dimensions 4 m x 5 m x 2.8 m in which all walls are internally coated with 2 cm thickness granites and considering the annual exposure time of 7000 h, suggested by the European Commission on Radiological Protection for superficial coating materials. The internal exposure was evaluated from radon air concentration of the model room, simulated from an exhalation rate of 222Rn, determined with CR-39 solid state nuclear track detectors by the sealed can technique, considering a ventilation rate of 0.5 h-1 and the same annual exposure time of 7000 h. The results for external gamma rays showed an increase in the annual effective dose ranging from 96 ± 4 μSv.a-1 to 223 ± 7 μSv.a-1 and, for radon inhalation, an increase in the ranging from 0.4 ± 0.04 μSv.a-1 to 70 ± 4 μSv.a-1. All results stayed below the recommended value by the European Commission on Radiological Protection, of 1 mSv.a-1.

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  • IPEN-DOC 27849

    CAVALCANTE, F. ; NISTI, M.B. ; SAUEIA, C.H.R. . Estimation of exposure levels of terrestrial biota and radiation exposure around IPEN’s facilities. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-13, 2021. DOI: 10.15392/bjrs.v9i1A.1235

    Abstract: Humans are exposed to natural radiation; soil is a major source of external and internal exposure of radiation. The aim of this study is to evaluate the exposure levels of terrestrial biota and to estimate the radiation exposure around Instituto of Pesquisas Energéticas e Nucleares (IPEN) facilities. The ERICA Tool was used to calculate the exposure levels of terrestrial biota; the estimation of radiation exposure for humans was determined using a model proposed by UNSCEAR and Excess Lifetime Cancer Risk. Six soil points were collected and their activity concentrations were measured by gamma spectrometry. Two soil points showed a risk coefficient greater than 1, suggesting that the screening dose ratio of 10μGy h-1 might be exceeding for the most exposed species, namely lichen and bryophytes, even though the activity concentration values of the analyzed radionuclides showed no evidence of soil contamination due to the atmospheric discharges of the IPEN facilities. Thus, the radioactive discharges in the soil from all facilities are negligible. Hence, the authors concluded that the ERICA Tool can be useful in assisting environmental radiological monitoring program for decision-making, especially regarding: points collected, sample types and sampling frequency.

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  • IPEN-DOC 27848

    VILLAS BOAS, C.A.W. ; DIAS, L.A.P. ; MATSUDA, M.M.N. ; ARAUJO, E.B. . Stability in production and transport of 177Lu labeled PSMA. Brazilian Journal of Radiation Sciences, v. 9, n. 1, p. 1-12, 2021. DOI: 10.15392/bjrs.v9i1.1619

    Abstract: In Brazil, prostate cancer is a common disease among men. The radionuclide therapy with PSMA analogs, labeled with beta and alpha emitters, has brought new perspectives for patients with multi metastatic resistant prostate cancer. The commercialization of radiopharmaceutical becomes a challenge to transport and ensure the quality of the product, especially in terms of radiochemical stability of therapeutic radiopharmaceuticals. The effect of radiolysis on therapeutic doses of radiopharmaceuticals can be avoided or mitigated by diluting the final dose and reducing storage and transportation temperature. This study evaluated the effect of radiolysis on the different radioactive concentration in the industrial batches of 177Lu-PSMA-617 and in the fractionated doses, considering long time transportation. The radiopharmaceutical 177Lu-PSMA-617 was produced in batches reaching 37 GBq, and stability studies were performed in controlled conditions. The results showed that a combination of factors, including reaction buffer, the radioactive concentration of final product, and freezing storage contributed to the stability of the radiopharmaceutical for 48 hours, enabling transport of 177Lu-PSMA-617 to distant regions of the country.

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  • IPEN-DOC 27847

    SILVA, A.L.C.; SILVA, A.T. . Comparison of computer programs to analyze the irradiation performance of U-Mo monolithic fuel plates and UO2 cylindrical fuel rods in power reactors. Brazilian Journal of Radiation Sciences, v. 9, n. 1, p. 1-17, 2021. DOI: 10.15392/bjrs.v9i1.1604

    Abstract: The aim of this work is to present a comparative analysis in terms of the irradiation performance of cylindrical uranium dioxide fuel rods and monolithic uranium molybdenum fuel plates in pressurized light water reactors. To analyze the irradiation performance of monolithic uranium molybdenum fuel plates when subjected to steady state operating conditions in light water pressurized reactors, the computer program PADPLAC-UMo was used, which performs thermal and mechanical analysis of the fuel taking into account the physical , chemicals and irradiation effects to which this fuel is subjected. For the analysis of the uranium dioxide fuel rods, the code FRAPCON was used, which is an analytical tool that verifies the irradiation performance of fuel rods of pressurized light water reactor, when the power variations and the boundary conditions are slow enough for the term permanent regime to be applied. The analysis for a small nuclear power reactor, despite the higher power density applied to the fuel plate in relation to the fuel rod, showed that the fuel plates have lower temperatures and lower fission gas releases throughout the analyzed power history, allowing the use of a more compact reactor core without exceeding the design limits imposed on nuclear fuel.

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  • IPEN-DOC 27846

    NEGRO, M.L.N. ; DURAZZO, M. ; MESQUITA, M.A.; SCURO, N.L. ; CARVALHO, E.F.U. ; ANDRADE, D.A. . A simulation model for capacity planning of nuclear fuel plants for research reactors. Brazilian Journal of Radiation Sciences, v. 9, n. 1, p. 1-28, 2021. DOI: 10.15392/bjrs.v9i1.1588

    Abstract: The demand for nuclear fuel for research reactors is increasing worldwide. However, some nuclear fuel factories have low production volumes. Literature regarding how to expand the capacity of those facilities in a safe and reliable way is scarce. Thus, the purpose of this work is to propose and validate a conceptual model for increasing the production capacity of such factories. The facilities addressed here are those that produce plate-type fuel elements loaded with LEU U3Si2-Al, which are typically used in nuclear research reactors. Data from a real nuclear fuel plant was collected and applied to the model, thus setting up a case study. Two different strategies, as well as several production scenarios, were conceived for the use of the model. Each scenario experiments with the different possibilities of enlarging capacity. Discrete events simulation was used in order to cover all production scenarios. The tests indicated significant increases in productive capacity, thus showing that the model fully achieved its proposed objective. One of the main conclusions to be highlighted is the model’s effectiveness, which was demonstrated by using the model in two different strategies and obtaining increases in capacity with both of them.

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  • IPEN-DOC 27845

    QUEIROZ, CARLOS A. da S. ; PEDREIRA FILHO, WALTER dos R.. Production of high purity samarium acetate for use in nuclear area. Brazilian Journal of Radiation Sciences, v. 9, n. 1, p. 1-14, 2021. DOI: 10.15392/bjrs.v9i1.1265

    Abstract: Samarium is currently used in many applications, such as catalysts, lasers and metal alloys. Samarium is also employed to absorb neutrons in nuclear reactors. In medicine, samarium is used in the form of radioactive 153Sm to produce radiopharmaceuticals. A simple process for the preparation of pure samarium acetate was studied. The raw material, which was used in the form of rare earth carbonates was produced industrially from the chemical treatment of Brazilian monazite. Ion exchange chromatography was performed using a strong cationic resin to fractionate rare earth elements (REE). Under these conditions, 99.9% pure Sm2O3 and yield greater than or equal 60% was eluted by ammonium salt of ethylenediaminetetraacetic acid (EDTA) solution in con-trolled pH. The EDTA-samarium complex was transformed into samarium oxide, which was subsequently dis-solved in acetic acid to obtain the samarium acetate. Molecular absorption spectrophotometry was used to moni-tor the samarium and sector field inductively coupled plasma mass spectrometry was used to certify the purity of the samarium acetate. The solid salt was characterized by chemical analysis, thermal analysis, infrared spectros-copy and X ray diffraction. The analytical data collected allowed to conclude that stoichiometric formula for the samarium acetate obtained is Sm(CH3COO)3.4.H2O.

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  • IPEN-DOC 27844

    PEREIRA, IRACI M. ; MORAES, DAVI A. . Monitoring system for an experimental facility using GMDH methodology. Brazilian Journal of Radiation Sciences, v. 8, n. 3B, p. 1-12, 2021. DOI: 10.15392/bjrs.v8i3B.663

    Abstract: This work presents a Monitoring System based on the GMDH - Group Method of Data Handling methodology applied in an Experimental Test Facility. GMDH is a combinatorial multi-layer algorithm in which a network of layers and nodes is generated using a number of inputs from the data stream being evaluated. The GMDH method is based on an underlying assumption that the data can be modeled by using an approximation of the Volterra Series or Kolmorgorov-Gabor polynomial. The Fault Test Experimental Facility was designed inspired in a PWR nuclear power plant and is composed by elements that correspond to the pressure vessel, steam generator, pumps of the primary and secondary reactor loops. The nuclear reactor core is represented by an electrical heater with different values of power. The exper-imental plant is fully instrumented with sensors and actuators. The Fault Test Experimental Facility can be operated to generate normal and faulty data. These failures can be added initially with small magnitude, and their magnitude being increasing gradually in a controlled way. The database will interface with the plant supervisory system SCADA (Super-visory Control and Data Acquisition) that provides the data through standard interface.

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  • IPEN-DOC 27843

    CASTRO, MAYSA C. ; SILVA, NATALIA F. ; CALDAS, LINDA V.E. . Performance of an extrapolation chamber in computed tomography standard beams. Brazilian Journal of Radiation Sciences, v. 8, n. 3B, p. 1-8, 2021. DOI: 10.15392/bjrs.v8i3B.376

    Abstract: Among the medical uses of ionizing radiations, the computed tomography (CT) diagnostic exams are responsible for the highest dose values to the patients. The dosimetry procedure in CT scanner beams makes use of pencil ionization chambers with sensitive volume lengths of 10 cm. The aim of its calibration is to compare the values that are obtained with the instrument to be calibrated and a standard reference system. However, there is no primary standard system for this kind of radiation beam. Therefore, an extrapolation ionization chamber, built at the Calibration Laboratory (LCI), was used to establish a CT primary standard. The objective of this work was to perform some characterization tests (short- and medium-term stabilities, saturation curve, polarity effect and ion collection efficiency) in the standard X-ray beams established for computed tomography at the LCI.

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  • IPEN-DOC 27842

    FREIRE, BRUNA M.; GONZAGA, ROBERTA G.; PEDRON, TATIANA; MONTEIRO, LUCILENA R. ; LANGE, CAMILA N.; PEDREIRA FILHO, WALTER dos R.; BATISTA, BRUNO L.. Occupational exposure to potentially toxic elements in the foundry industry: an integrated environmental and biological monitoring. Environmental Science and Pollution Research, v. 28, n. 26, p. 34630-34641, 2021. DOI: 10.1007/s11356-021-13099-y

    Abstract: Industrial foundry processes release metal dust and fumes into the environment. Our study evaluated the exposure to potentially toxic elements in foundry workers. The assessed samples consisted of air particulate matter (n = 42), urine (n = 194), and blood (n = 167). Six workers had high concentrations of arsenic (As) in urine and one of them had a high cadmium (Cd) content in blood, according to Biological Exposure Index from the American Conference of Governmental Industrial Hygienists. The work task significantly influenced the concentrations of cobalt (Co), copper (Cu), iron (Fe), and manganese (Mn) in air, barium (Ba) in urine, and lead (Pb) and cesium (Cs) in blood, while the employment years affected concentrations of Mn, tin (Sn), and uranium (U) in urine and iodine (I) in blood. Arsenic, Pb, Co, and Cd in particulate matter and biological matrices presented significant covariation by working activity, supporting the occupational exposure. In this study, subjects were occupationally exposed to multiple potentially toxic elements. Carcinogenic and noncarcinogenic risks were associated with As, Co, Ni, and Mn exposure.

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  • IPEN-DOC 27841

    BERGAMO, EDMARA T.P.; CARDOSO, KARINA B.; LINO, LUCAS F.O.; CAMPOS, TIAGO M.B.; MONTEIRO, KELLI N.; CESAR, PAULO F.; GENOVA, LUIS A. ; THIM, GILMAR P.; COELHO, PAULO G.; BONFANTE, ESTEVAM A.. Alumina-toughened zirconia for dental applications: physicochemical, mechanical, optical, and residual stress characterization after artificial aging. Journal of Biomedical Materials Research Part B: Applied Biomaterials, v. 109, n. 8, p. 1135-1144, 2021. DOI: 10.1002/jbm.b.34776

    Abstract: To characterize the physicomechanical properties of an alumina-toughened zirconia (ATZ). ATZ synthesis consisted of the addition of alumina particles in an yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP) matrix. Specimens were obtained by uniaxial and isostatic pressing ATZ and 3Y-TZP powders and sintering at 1600°C/1 h and 1550°C/1 h, respectively. Crystalline content and residual stress were evaluated using X-ray diffraction (XRD). Microstructure was characterized by scanning electron microscopy (SEM). Optical properties were determined by reflectance test. Mechanical properties were assessed by biaxial flexural strength test. All analyses were performed before and after aging (134°C, 20 h, 2 bar). XRD and SEM revealed a typical ATZ and 3Y-TZP crystalline content, chiefly tetragonal phase, with a dense polycrystalline matrix, though a smaller grain size for ATZ. Aging triggered a similar monoclinic transformation for both systems; however, ATZ exhibited higher residual compressive stresses than 3Y-TZP. While as-processed 3Y-TZP demonstrated significantly higher characteristic strength relative to ATZ, no significant difference was observed after aging (~215 MPa increase in the ATZ strength). ATZ presented significantly higher opacity relative to 3Y-TZP, although aging significantly increased the translucency of both systems (increase difference significantly higher in the 3Y-TZP compared to ATZ). ATZ physicomechanical properties support its applicability in the dental field, with a lower detrimental effect of aging relative to 3Y-TZP.

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  • IPEN-DOC 27840

    ROSA, JORGE M. ; MELO, CAMILA G. ; PEREIRA, MARIA da C.C. ; BORRELY, SUELI I. . Reactive Blue 21 exhaustion degree investigated using the surface response methodology as an auxiliary tool in cotton dyeing. Journal of Natural Fibers, v. 18, n. 4, p. 520-530, 2021. DOI: 10.1080/15440478.2019.1636739

    Abstract: Response surface methodology was used to investigate the influences of sodium chloride (NaCl), soda ash (Na2CO3), and sodium hydroxide (NaOH) concentrations on cotton and the degree of exhaustion (DE) of Reactive Blue 21 dyestuff (RB21), as well as to optimize dyeing conditions. A 23 central composite and rotational design was used as a support to carry out 17 dyeings with RB21 on a 100% knitted cotton substrate. NaCl, Na2CO3, and NaOH concentrations were used as factors. Responses comprised color strength (K S‒1) and the DE. The results indicate that a square model was the best fit. This model was able to increase both K S‒1 and DE values, with the colorfastness to water and rubbing carried out with supplier’s formulation recipe. This study demonstrates that the use of the response surface methodology in color matching can contribute to the textile industry in the prediction or assessment of formulations for a specific color.

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  • IPEN-DOC 27839

    LUCAS-SOLIS, OSCAR; MOULATLET, GABRIEL M.; GUAMANGALLO, JENIFFER; YACELGA, NAOMI; VILLEGAS, LIPSI; GALARZA, EMILY; ROSERO, BRYAN; ZURITA, BRYAN; SABANDO, LIZETH; CABRERA, MARCELA; GIMILIANI, GIOVANA T. ; CAPPARELLI, MARIANA V.. Preliminary assessment of plastic litter and microplastic contamination in freshwater depositional areas: the case study of Puerto Misahualli, Ecuadorian Amazonia. Bulletin of Environmental Contamination and Toxicology, v. 107, n. 1, p. 45-51, 2021. DOI: 10.1007/s00128-021-03138-2

    Abstract: We quantify plastic litter (PL, > 2 cm) and microplastics (MP, < 5 mm) from the sediments of a beach formed at a riverine depositional area, at the upper Amazon River basin, Ecuador. In the collection area (4400 m2), the PL density was 0.045 items m−2, where low-density polyethylene bags were the prevalent PL. The beach was classified as “very clean” (Clean Coast Index (CCI) of 1.3 items m−2). Regarding MP, in 55 sampling stations, average MP concentrations ranged from 0 to 2200 items kg−1 of dry sediment (0.5–2 mm), and 0–4200 items kg−1 of dry sediment (2–5 mm). Blue fibers were the prevalent MP. Our results represent the first report to show the ubiquitous presence of PL and MP for the area. The monitoring and management of plastic disposal in freshwater beaches are necessary, as here we report a small part of an undocumented issue.

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  • IPEN-DOC 27838

    THEOPHILO, CAROLINA Y.S. ; RIBEIRO, ANDREZA P.; MOREIRA, EDSON G. ; ARANHA, SIDNEI; BOLLMANN, HARRY A.; SANTOS, CLEITON J.; OLIVEIRA, ANDERSON de; SANTOS, SIDNEY dos; SAIKI, MITIKO ; SALDIVA, PAULO H.N.; FERREIRA, MAURICIO L.. Biomonitoring as a nature‐based solution to assess atmospheric pollution and impacts on public health. Bulletin of Environmental Contamination and Toxicology, v. 107, n. 1, p. 29-36, 2021. DOI: 10.1007/s00128-021-03205-8

    Abstract: The control of air pollution remains a challenge to the planning of cities and fossil fuel burning is the main cause of air degradation. Particulate matter (PM) is the contaminant commonly used as an indicator of pollution, but environmental agencies may face difficulties in operating surveillance networks due to the lack of resources and infrastructure. As an alternative to conventional networks, scientific studies have pointed out that nature itself can contribute to the diagnosis and reduction of air pollution. Nature-based solutions (NbS) are proposals that use natural processes and structures to meet different environmental challenges. In this study, biomonitoring with Tillandsia usneoides was applied as a NbS tool to evaluate air quality in an important port urban area in the city of Guarujá, Brazil, affected by industrial and vehicular emissions. It was observed that cadmium mass fractions were at least forty times higher than the control area with one-month exposition.

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  • IPEN-DOC 27837

    FERREIRA, MERILYN S. ; WETTER, NIKLAUS U. . Diode-side-pumped, intracavity Nd:YLF/KGW/LBO Raman laser at 573 nm for retinal photocoagulation. Optics Letters, v. 46, n. 3, p. 508-511, 2021. DOI: 10.1364/OL.411895

    Abstract: Wavelengths in the yellow-orange range are of significant interest for retinal photocoagulation and are especially important in the case of diabetic retinopathy, which can cause blindness and affects 3.3% of all working-age adults. This work presents a highly-efficient, compact, and cost-efficient side-pumped, intracavity Raman configuration to achieve this objective. A side-pumped Nd:YLF/KGW/LBO frequency-doubled Raman laser producing 11.7 W of output power at 1147 nm with 21% of slope efficiency and 6 W of output power at 573.5 nm with 12% slope efficiency is demonstrated.

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  • IPEN-DOC 27836

    LIMA, VERA M.F. de ; HANKE, WOLFGANG. Reversibility of excitation waves in brain and heart and the energy of interfacial water: Can reversibility be explained by it?. Progress in Biophysics and Molecular Biology, v. 162, p. 129-140, 2021. DOI: 10.1016/j.pbiomolbio.2020.11.002

    Abstract: In this manuscript, we interpret the implications of a discovery we made in 1993 for the understanding of the spread of excitation waves in axon, central gray matter (isolated retina) and heart. We propose that the initial burst of energy dissipation in these waves measured as potentials drops, ionic activities marked changes or optical properties being mostly the effect of dissociated water becoming liquid water and be reversible due to the further on dissociation during the refractory period. We also propose experiments in order to falsify or agree with this conjecture.

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  • IPEN-DOC 27835

    STEFANI, GIOVANNI L. de ; MAIORINO, JOSE R.; MOREIRA, JOAO M. de L.. The AP-Th 1000: an advanced concept to use MOX of thorium in a closed fuel cycle. International Journal of Energy Research, v. 45, n. 8, SI, p. 11642-11655, 2021. DOI: 10.1002/er.5421

    Abstract: This work presents the feasibility studies to convert the UO2 core of the Westinghouse AP1000 reactor to a U/Th core aiming at U/Th fuel recycling. The focus of the work is to establish a first core which allows normal operation of the AP1000 reactor and investigate a possible route for generating the 233U for U/Th fuel recycling. The converted core named AP-Th1000 is divided in three homogenous zones with different UO2/ThO2 mass proportions. The reprocessing procedure envisioned is to separate fission products and Pu isotopes, retain Uranium, use this fuel material in subsequent fuel cycles and complement the required fissile material with U with enrichment below 20%. The goal was to gradually reduce the mass proportion of mined Uranium fuel and eventually attain a Th-233U core with similar operation characteristics of current AP1000 core. We perform a detailed three-dimensional full core analysis with the SERPENT code examining core reactivity, power density distribution, and also a preliminary closed cycle study for the first 4 cycles where the production of 233U are evaluated. The goal of converting the AP1000 reactor core to a U/ThO2 fuel cycle was partially accomplished. While the first cycle was thoroughly examined and met all requirements we were not able to find a route to migrate it to a prevalent Th cycle. Basically, two of the set of criteria adopted in the study proved to be too restrictive to attain this goal with homogenous assembly, namely U enrichment below 20% and not recycling Pu. The results indicate that removing these two criteria the conversion factor in the ensuing fuel cycles can be increased and possibly attain a Th cycle without compromising the economics of power generation. The design changes were the elimination of IFBA burnable absorbers and replacement of gray control bundles by black control bundles.

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  • IPEN-DOC 27834

    PEREIRA, SAULO T. ; SILVA, CAMILA R. ; NUNEZ, SILVIA C.; RIBEIRO, MARTHA S. . Safety and clinical impact of a single red light irradiation on breast tumor-bearing mice. Photochemistry and Photobiology, v. 97, n. 2, p. 435-442, 2021. DOI: 10.1111/php.13338

    Abstract: Low-level light therapy has been used in health care as a therapeutic strategy for different diseases. However, its effects on cancer are controversial. This work evaluated the effects of three energies on breast cancer-bearing mice after a single red light-emitting diode (LED) irradiation. 4T1 cells were inoculated into the mammary fat pad of female BALB/c mice. When tumor volume reached 100 mm3, animals were irradiated by a LED irradiator (660 ± 11 nm) with energies of 1.2, 3.6, and 6.0 J. Control without irradiation and healthy animals were also evaluated. Mice were monitored regarding tumor volume and total blood count. After euthanasia, their organs were examined. We observed that a single irradiation does not increase tumor volume. All irradiated groups exhibited better clinical conditions than control, which presented a significant decrease in platelet and red blood cell levels compared with healthy mice. The energy of 3.6 J arrested neutrophil-lymphocyte rate besides promoting longer survival and a lower number of metastatic nodules in the lungs. These findings suggest that a single red LED irradiation causes no impact on the course of the disease. Besides, the intermediary dose-effect should be further investigated since it seems to promote better outcomes on breast cancer-bearing mice.

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  • IPEN-DOC 27833

    KOTSAKIS, GEORGIOS A.; BLACK, RACHEL; KUM, JASON; BERBEL, LARISSA ; SADR, ALI; KAROUSSIS, IOANNIS; SIMOPOULOU, MARA; DAUBERT, DIANE. Effect of implant cleaning on titanium particle dissolution and cytocompatibility. Journal of Periodontology, v. 92, n. 4, p. 580-591, 2021. DOI: 10.1002/JPER.20-0186

    Abstract: Background Peri-implantitis treatments are mainly based on protocols for teeth but have not shown favorable outcomes for implants. The potential role of titanium dissolution products in peri-implantitis necessitate the consideration of material properties in devising treatment protocols. We assessed implant cleaning interventions on (1) bacterial removal from Ti-bound biofilms, (2) Ti surface alterations and related Ti particle dissolution, and (3) cytocompatibility. Methods Acid-etched Ti discs were inoculated with human peri-implant plaque biofilms and mechanical antimicrobial interventions were applied on the Ti-bound biofilms for 30 seconds each: (1) rotary nylon brush; (2) Ti brush; (3) water-jet on high and (4) low, and compared to sterile, untreated and Chlorhexidine-treated controls. We assessed colony forming units (CFU) counts, biofilm removal, surface changes via scanning electron microscopy (SEM) and atomic force microscopy (AFM), and Ti dissolution via light microscopy and Inductively-coupled Mass Spectrometry (ICP-MS). Biological effects of Ti particles and surfaces changes were assessed using NIH/3T3 fibroblasts and MG-63 osteoblastic cell lines, respectively. Results Sequencing revealed that the human biofilm model supported a diverse biofilm including known peri-implant pathogens. WJ and Nylon brush were most effective in reducing CFU counts (P < 0.01 versus control), whereas Chlorhexidine was least effective; biofilm imaging results were confirmatory. Ti brushes led to visible streaks on the treated surfaces, reduced corrosion resistance and increased Ti dissolution over 30 days of material aging as compared to controls, which increase was amplified in the presence of bacteria (all P-val < 0.05). Ti particles exerted cytotoxic effects against fibroblasts, whereas surfaces altered by Ti brushes exhibited reduced osteoconductivity versus controls (P < 0.05). Conclusions Present findings support that mechanical treatment strategies selected for implant biofilm removal may lead to Ti dissolution. Ti dissolution should become an important consideration in the clinical selection of peri-implantitis treatments and a necessary criterion for the regulatory approval of instruments for implant hygiene.

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  • IPEN-DOC 27832

    SANTOS, S.C. ; RODRIGUES JUNIOR, O. ; CAMPOS, L.L. . Dispersion of thulium-yttria nanoparticles to build up smart structures. Materials Today Communications, v. 26, p. 1-7, 2021. DOI: 10.1016/j.mtcomm.2020.101749

    Abstract: The development of new materials for radiation dosimetry is a challenge to assure quality improvement practices related to radiation protection concept. On this context, colloidal stability provides conditions to build up smart structured materials from bottom-up perspective. The present work reports zeta potential characterization of thulium-yttria nanoparticles in aqueous medium. Thulium-yttria nanoparticles formed by a relative low temperature hydrotermal synthesis were characterized by XRD, PCS, and SEM. The stability of particles in aqueous medium was evaluated by electrophoretic mobility measurements, followed by zeta potential calculation. The results revealed that the isoelectric point of thulium-yttria suspensions shifted in accordance with thulium concentration from pH 8.5 (“pure” yttria) to pH 9.2 (2at.%Tm). Besides, most suspensions could be stabilized at pH 10.5, presenting zeta potential values around 30 mV. These results are substantial parameters to advance toward new materials for radiation dosimetry.

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  • IPEN-DOC 27831

    AQUINO, SIMONE ; LIMA, JOSE E.A. de; SILVA, MOISES O. da; SOUSA, GABRIELA F. de. Multidrug-resistant bacteria isolated from automated teller machine in metropolitan area of São Paulo, Brazil. World Journal of Biology Pharmacy and Health Sciences, v. 5, n. 1, p. 27-36, 2021. DOI: 10.30574/wjbphs.2021.5.1.0002

    Abstract: The aim of this study was to investigate bacterial contamination on surfaces of randomly selected Automated Teller Machine and their sensitivity to antibiotics in São Paulo city, Brazil. The swabs collected aseptically were inoculated in selective and non-selective media in triplicate and incubated at 37 °C for 24 h. After Gram staining the isolated colonies, complementary biochemical tests were applied. The antibiotic sensitivity pattern of all isolates (15 Gram-positive bacteria and 7 Gram-negative bacteria) was determined using the Kirk Bauer method using chloramphenicol, clindamycin, norfloxacin, erythromycin, gentamicin and tetracycline diffusion discs. All ATM surfaces tested were contaminated with at least one genus of bacteria. The most frequently isolated bacteria were Staphylococcus aureus (64%), Enterococcus spp. (28%) and Acinetobacter spp. (21%), followed by coagulase-negative staphylococci (14%), Pseudomonas spp. in 12 (14%), Salmonella spp. (7%), Escherichia coli (7%). ATMs in the São Paulo metropolitan region were shown to be contaminated with bacteria that are resistant to the commonly used antibiotics. All Gram-negative and Gram-positive bacteria isolated were multidrug-resistant, however, the strains were sensitive (S) or showed an intermediate response profile (I) to tetracycline, with the exception of three strains of Pseudomonas spp., Acinetobacter spp. and Staphylococcus aureus, which were resistant to tetracycline. Norfloxacin and gentamicin showed resistance response profile to all bacteria. Based on these findings, it is recommended to perform hand washing and use of antiseptics after using ATMs.

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  • IPEN-DOC 27830

    MOREIRA, GREGORI de A. ; ANDRADE, IZABEL da S. ; CACHEFFO, ALEXANDRE ; YOSHIDA, ALEXANDRE C. ; GOMES, ANTONIO A. ; SILVA, JONATAN J. da ; LOPES, FABIO J. da S. ; LANDULFO, EDUARDO . COVID-19 outbreak and air quality: analyzing the influence of physical distancing and the resumption of activities in São Paulo municipality. Urban Climate, v. 37, p. 1-15, 2021. DOI: 10.1016/j.uclim.2021.100813

    Abstract: This work compares variations in the concentrations and air quality indexes of the pollutants PM10, PM2.5, CO, and NO2, during the COVID-19 outbreak in São Paulo Municipality. Such comparisons considered the period of physical distancing (autumn) and the three first months of economic activities’ resumption (winter). The concentrations and indexes observed in 2020 were compared with their correspondent values measured in the three preceding years. Also, from a supervised machine learning algorithm, the correspondent 2020 expected values were predicted and used in these comparisons. In order to analyze the influence of meteorological conditions, the seasons studied were characterized using remote sensing and surface data. The pollutants predominantly emitted by the vehicle fleet (CO and NO2) had reductions in their concentrations, with values always below the predictions and good air quality indexes. However, the pollutants whose concentration is less dependent on automotive emissions (PM10 and PM2.5) had high proximity to the predictions during the autumn and lower values during some periods in winter. This reduction was not enough to avoid days with a moderate air quality index. The approximation of the average concentrations of PM10, PM2.5, and CO to the prediction, from the second-half August 2020, indicates the influence of activities’ resumption in air quality.

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  • IPEN-DOC 27829

    SILVA, REJANE M.P. da ; IZQUIERDO, JAVIER; MILAGRE, MARIANA X. ; BETANCOR-ABREU, ABENCHARA M.; COSTA, ISOLDA ; SOUTO, RICARDO M.. Use of amperometric and potentiometric probes in scanning electrochemical microscopy for the spatially-resolved monitoring of severe localized corrosion sites on aluminum alloy 2098-T351. Sensors, v. 21, n. 4, p. 1-15, 2021. DOI: 10.3390/s21041132

    Abstract: Amperometric and potentiometric probes were employed for the detection and characterization of reactive sites on the 2098-T351 Al-alloy (AA2098-T351) using scanning electrochemical microscopy (SECM). Firstly, the probe of concept was performed on a model Mg-Al galvanic pair system using SECM in the amperometric and potentiometric operation modes, in order to address the responsiveness of the probes for the characterization of this galvanic pair system. Next, these sensing probes were employed to characterize the 2098-T351 alloy surface immersed in a saline aqueous solution at ambient temperature. The distribution of reactive sites and the local pH changes associated with severe localized corrosion (SLC) on the alloy surface were imaged and subsequently studied. Higher hydrogen evolution, lower oxygen depletion and acidification occurred at the SLC sites developed on the 2098-T351 Al-alloy.

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  • IPEN-DOC 27828

    PARRA, DUCLERC F. ; MARCHINI, LEONARDO G. ; KOMATSU, LUIZ G.H. ; OLIVEIRA, CAMILA B. de ; OLIANI, WASHINGTON L. ; RANGARI, VIJAYA K.. AgNPs@ZnO hybride nanoparticles infused thermoplastic polyester elastomer and their biocide effect. SN Applied Sciences, v. 3, n. 4, 2021. DOI: 10.1007/s42452-021-04365-2

    Abstract: This paper presents research results of biocidal effect of thermoplastic- polyester-elastomer (TPE-E) with incorporation of hybrid Ag/ZnO/SiO2 NPs (silver/Zinc oxide/SiO2 nanoparticles). These results were compared with various gamma-irradiated doses and processing techniques including extrusion, injection molding and compression molding. In all these processing techniques the TPE-E was mixed with mineral oil and Ag/ZnO/SiO2 nanoparticles. The TPE-E nanocomposites were characterized by differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), Infrared FT spectroscopy (FTIR), surface enhanced Raman technique (SERS), FESEM (Field emission scanning electron microscopy), Energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), TEM (transmission electronic microscopy) and antimicrobial test. Antibacterial activity against E. coli and S. aureus, are reported and these results showed potential application in health care products.

    Palavras-Chave: gamma radiation; irradiation; antibiotics; nanoparticles; silver; processing; thermoplastics

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  • IPEN-DOC 27827

    SILVA, GRACIA M.G.; AQUINO, SIMONE ; MORGADO, FLAVIO. Proposal for pre-surgery nursing care: reduction of surgical cancellations by users of the Unified Health System / Proposta de acolhimento pré-operatório de enfermagem: redução de cancelamentos cirúrgicos de usuários do Sistema Único de Saúde. Revista de Gestão em Sistemas de Saúde, v. 10, n. 1, p. 45-60, 2021. DOI: 10.5585/rgss.v10i1.17915

    Abstract: Canceling surgeries creates stress for the patient and burdens the institution, reflecting inefficiency in hospital administration. The present study, designed as a quantitative, observational, descriptive, retrospective, prospective and cross-sectional research, analyzed the scheduled, performed and suspended surgeries of the Unified Health System (with the highest percentage of cancellations), in a teaching hospital, categorized by specialty, reason for suspension and source of payment, from the years 2014 to 2017. The study proposes a nursing intervention system, in order to reduce the cancellation of UHS surgeries, based on a nursing consultation and active search (telephone contact with the patient or family member), 48 hours before surgery. The study, carried out with 159 UHS patients with scheduled elective surgeries, found that the average of surgical suspensions was 17%, above the general historical average (10.5%) and the historical average of UHS (14%). After the intervention, the observed suspension rate was 15.3%, lower than the rate of 22%, when there was no prior contact.

    Palavras-Chave: medical personnel; patient; surgery; hospitals; public health; cancellation; planning

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  • IPEN-DOC 27826

    SAVI, M. ; VILLANI, D. ; ANDRADE, M.A.B.; RODRIGUES JUNIOR, O. ; POTIENS, M.P.A. . Study on attenuation of 3D printing commercial filaments on standard X-ray beams for dosimetry and tissue equivalence. Radiation Physics and Chemistry, v. 182, p. 1-7, 2021. DOI: 10.1016/j.radphyschem.2021.109365

    Abstract: 3D printing techniques and materials have become widely available in the last couple of decades and remains an important topic of research as the equipments and supplements gets chipper. This study aims to evaluate the attenuation behaviour of several commercially available 3D printing filaments (ABS and PLA-based filaments and other polymers blends) over standard X-ray beams ranging from ~30 keV - to ~50 keV and comparing the experimental results with theoretical data of Cortical Bone, Soft Tissue and PMMA. It was used the transmission method to obtain experimental attenuation coefficients to all materials. HVL for the materials were also calculated. Results show that PLA-based printing filaments mixed with metals (Al, BRASS and Cu) has higher attenuation than pure PLA. Comparing the experimental data with theoretical cross section of Soft Tissue, Cortical Bone and PMMA, it was possible to observe that with the increase of beam energy, ABS-based and other blends’ attenuation behaviour agree with PMMA/Soft tissue. None of the studied materials showed agreement of attenuation with Cortical Bone. Some variations of PLA (SILK, Black and Bone) and some of the other blends of PETG and TPU showed good agreement with Soft Tissue/PMMA since about 30 keV and it can be concluded that these filaments can be used as substitute of PMMA for mimetizing soft tissue in 3D printed phantoms.

    Palavras-Chave: attenuation; coefficient of performance; photon beams; bone tissues; radiations; particle beams; phantoms; 3d printing

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  • IPEN-DOC 27825

    NAGAI, MARIA L.E. ; SANTOS, PAULO de S. ; OTUBO, LARISSA ; OLIVEIRA, MARIA J.A. ; VASQUEZ, PABLO A.S. . Gamma and electron beam irradiation effects for conservation treatment of cellulose triacetate photographic and cinematographic films. Radiation Physics and Chemistry, v. 182, p. 1-10, 2021. DOI: 10.1016/j.radphyschem.2021.109395

    Abstract: Photographic and cinematographic films of cellulose triacetate safeguarded in historical and cultural institutions are often contaminated by fungi when stored in inadequate conditions of humidity and temperature. The presence of fungi affects the image contained in the films, accelerates the process of biodeterioration and represents a risk to the health of people working with contaminated materials. In addition, another common physicochemical degradation affecting cellulose triacetate films causing deacetylation of polymer chain is called “vinegar syndrome”. Considering the dose interval established for the disinfection of cultural heritage materials, in this work the effects of irradiation with gamma rays and electron beam on photographic and cinematographic films of cellulose triacetate were evaluated. Additionally, the thermal stability behavior of the films and the feasibility of crosslinking of CTA films were investigated. Film samples were selected and characterized by FTIR-ATR spectroscopy. Irradiated samples by gamma rays and electron beam with radiation absorbed doses between 6 kGy and 200 kGy were examined by FEGSEM microscopy, UV–Vis spectrophotometry and differential scanning calorimetry (DSC). The results showed that disinfection by gamma and electron beam irradiation, in the dose range of 6 kGy–10 kGy, does not change or modification of main properties of the constitutive materials of photographic and cinematographic films. The applied dose of 50 kGy, both gamma rays and electron beam, indicated a crosslinking effect on the films and can be considered a possibility for the treatment of films affected by the “vinegar syndrome”.

    Palavras-Chave: photographic films; cinematography; cultural resources; electron beams; gamma radiation

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  • IPEN-DOC 27824

    SELLERA, FABIO P.; BARBOSA, BRUNA S.; GARGANO, RONALDO G.; RISPOLI, VIVIAN F.P.; SABINO, CAETANO P.; OLLHOFF, RUDIGER D.; BAPTISTA, MAURICIO S.; RIBEIRO, MARTHA S. ; SA, LILIAN R.M. de; POGLIANI, FABIO C.. Methylene blue-mediated antimicrobial photodynamic therapy can be a novel non-antibiotic platform for bovine digital dermatitis. Photodiagnosis and Photodynamic Therapy, v. 34, p. 1-8, 2021. DOI: 10.1016/j.pdpdt.2021.102274

    Abstract: Background Bovine digital dermatitis (BDD) is one of the most important diseases that effect dairy cows. Methylene blue-mediated antimicrobial photodynamic therapy (MB-APDT) emerges as a promising technique to treat superficial infections in bovines. Methods Twenty BDD lesions located at the skin horn transition of the claw of pelvic limbs of 16 cows were treated by MB-APDT, using a red LED cluster (λ = 660 nm, irradiance =60 mW/cm2, exposure time = 40 s) combined with topical application of MB at 0.01 %; or by topical application of OXY (500 mg in 20 % solution). Each lesion was treated twice with an interval of 14 days. Lesions were weekly evaluated until day 28 by clinical analysis and by histological examination on days 0 and 28. Results Both treatments led to a similar reduction of lesions area. At day 28, three lesions treated by OXY did not present completely recovery, whereas no lesions were observed in MB-APDT group. OXY resulted in a slight increase in type I and III collagen levels, while MB-APDT led to a significant increase in the total area of both collagen types. An abundant number of spirochetes were histologically observed in all lesions before treatments. On the 28th day, five lesions treated by OXY still presented a slight number of spirochetes, whereas in MB-APDT group no spirochetes were evidenced. Conclusion Our findings suggest that MB-APDT is more effective than OXY and could be used in Veterinary practice to fight BDD.

    Palavras-Chave: methylene blue; antimicrobial agents; cattle; inactivation; photosensitivity; therapy; dermatitis; infectious diseases

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  • IPEN-DOC 27823

    VALANDRO, PATRICIA; MASSUDA, MAYARA B.; RUSCH, ELIDIANE; BIRGEL, DANIELA B.; PEREIRA, PHILIPE P.L.; SELLERA, FABIO P.; RIBEIRO, MARTHA S. ; POGLIANI, FABIO C.; BIRGEL JUNIOR, EDUARDO H.. Antimicrobial photodynamic therapy can be an effective adjuvant for surgical wound healing in cattle. Photodiagnosis and Photodynamic Therapy, v. 33, p. 1-4, 2021. DOI: 10.1016/j.pdpdt.2020.102168

    Abstract: Background Rumenostomy is a useful procedure commonly performed in cattle for medical treatment of domestic ruminants with forestomach diseases. Methylene blue (MB)-mediated antimicrobial photodynamic therapy (APDT) has been broadly investigated to treat infected wounds. Aim The aim of the study was to evaluate the effectiveness of MB-mediated APDT (MB-APDT) combined with chlorhexidine and zinc oxide ointment on wound healing process after rumenostomy. Methods Fourteen Nelore bulls were subjected to rumenostomy procedure. Animals were randomly divided into MB-APDT (MB associated with a red diode laser performed immediately after surgery and repeated on days 3, 5, 7 and 10) and control groups. Daily care included topical cleaning with chlorhexidine 2% followed by topical zinc oxide ointment. Animals were followed-up until the 28th day. Results Wounds presented a better post-surgical profile in MB-APDT group when it was compared with the control group. In MB-APDT group, it was also possible to observe less pain on palpation of wounds borders, less edema and inflammatory exudate. Additionally, animals from MB-APDT group were faster discharged from the cattle care facility. Conclusion Our results support the use of MB-APDT for the post-surgical management of rumenostomy. This pilot study ratifies the use of APDT in cattle and also suggests that it could be performed for other surgical procedures as a complementary approach or an alternative for topical administration of antibiotics.

    Palavras-Chave: methylene blue; therapy; cattle; inactivation; veterinary medicine; surgery; wounds; healing

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  • IPEN-DOC 27822

    SARTORI, GISELLE P.; COSTA, ANDREA da; MACARINI, FERNANDO L. dos S.; MARIANO, DOUGLAS O.C.; PIMENTA, DANIEL C.; SPENCER, PATRICK J. ; NALI, LUIZ H. da S.; GALISTEO JUNIOR, ANDRES J.. Characterization and evaluation of the enzymatic activity of tetanus toxin submitted to cobalt-60 gamma radiation. Journal of Venomous Animals and Toxins including Tropical Diseases, v. 27, p. 1-13, 2021. DOI: 10.1590/1678-9199-JVATITD-2020-0140

    Abstract: Background Tetanus toxin blocks the release of the inhibitory neurotransmitters in the central nervous system and causes tetanus and its main form of prevention is through vaccination. The vaccine is produced by inactivation of tetanus toxin with formaldehyde, which may cause side effects. An alternative way is the use of ionizing radiation for inactivation of the toxin and also to improve the potential immunogenic response and to reduce the post-vaccination side effects. Therefore, the aim of this study was to characterize the tetanus toxin structure after different doses of ionizing radiation of 60Co. Methods Irradiated and native tetanus toxin was characterized by SDS PAGE in reducing and non-reducing conditions and MALD-TOF. Enzymatic activity was measured by FRET substrate. Also, antigenic properties were assessed by ELISA and Western Blot data. Results Characterization analysis revealed gradual modification on the tetanus toxin structure according to doses increase. Also, fragmentation and possible aggregations of the protein fragments were observed in higher doses. In the analysis of peptide preservation by enzymatic digestion and mass spectrometry, there was a slight modification in the identification up to the dose of 4 kGy. At subsequent doses, peptide identification was minimal. The analysis of the enzymatic activity by fluorescence showed 35 % attenuation in the activity even at higher doses. In the antigenic evaluation, anti-tetanus toxin antibodies were detected against the irradiated toxins at the different doses, with a gradual decrease as the dose increased, but remaining at satisfactory levels. Conclusion Ionizing radiation promoted structural changes in the tetanus toxin such as fragmentation and/or aggregation and attenuation of enzymatic activity as the dose increased, but antigenic recognition of the toxin remained at good levels indicating its possible use as an immunogen. However, studies of enzymatic activity of tetanus toxin irradiated with doses above 8 kGy should be further analyzed.

    Palavras-Chave: cobalt 60; detoxification; enzyme activity; gamma radiation; irradiation; neurology; radiation dose units; tetanus; toxins; vaccines

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  • IPEN-DOC 27821

    REZENDE, M.V.S.; PEREIRA, U.C.; REZENDE, Y.R.R.S.; CARVALHO, I.S.; SILVEIRA, W.S.; JUNOT, D.O. ; SILVA, R.S.; RESENDE, C.X.; FERREIRA, N.S.. Sustainable preparation of ixora flower-like shaped luminescent powder by recycling crab shell biowaste. Optik - International Journal for Light and Electron Optics, v. 235, p. 1-5, 2021. DOI: 10.1016/j.ijleo.2021.166636

    Abstract: We report on cost-effective recycling of crab shell biowaste and synthesis of luminescent powders. XRD, thermogravimetric and, FTIR analysis revealed that calcination temperature must be beyond ∼800 °C to recycle biowastes crab (Ucides cordatus) shell into crystalline powder composed of CaO, and a small amount of CaCO3, NaCa(PO4), MgO, and Ca₁₀(PO₄)₆(OH)₂. SEM analysis revealed that calcination of crab shell biowaste at 800 °C/2 h produced the homogeneous cauliflower- and ixora flower-like shaped intrinsic luminescent powders. XEOL and thermoluminescence analyses suggest that F+-centers of the CaO structure are responsible for the efficient intrinsic scintillation of the crab shell powder. Therefore, our study shows a biomaterial promise derived from seafood wastes as natural dosimeter materials for industrial applications.

    Palavras-Chave: biological wastes; recycling; seafood; crabs; luminescence; powders

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  • IPEN-DOC 27820

    PETERSEN, ALAN; TACCHEO, STEFANO; MIROV, SERGEY; NILSSON, JOHAN; PASK, HELEN; SARACENO, CLARA; WETTER, NIKLAUS ; WU, RUIFEN. Focus issue introduction: Advanced Solid-State Lasers 2020. Optics Express, v. 29, n. 6, p. 8365-8367, 2021. DOI: 10.1364/OE.423636

    Abstract: This Joint Issue of Optics Express and Optical Materials Express features 15 articles written by authors who participated in the international online conference Advanced Solid State Lasers held 13–16 October, 2020. This review provides a summary of the conference and these articles from the conference which sample the spectrum of solid state laser theory and experiment, from materials research to sources and from design innovation to applications.

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  • IPEN-DOC 27819

    PETERSEN, ALAN; TACCHEO, STEFANO; MIROV, SERGEY; NILSSON, JOHAN; PASK, HELEN; SARACENO, CLARA; WETTER, NIKLAUS ; WU, RUIFEN. Focus issue introduction: Advanced Solid-State Lasers 2020. Optical Materials Express, v. 11, n. 4, p. 952-954, 2021. DOI: 10.1364/OME.423641

    Abstract: This Joint Issue of Optics Express and Optical Materials Express features 15 articles written by authors who participated in the international online conference Advanced Solid State Lasers held 13–16 October, 2020. This review provides a summary of the conference and these articles from the conference which sample the spectrum of solid state laser theory and experiment, from materials research to sources and from design innovation to applications.

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  • IPEN-DOC 27818

    TANGTHONG, THEERANAN; PIROONPAN, THANANCHAI; THIPE, VELAPHI C. ; KHOOBCHANDANI, MENKA; KATTI, KAVITA; KATTI, KATTESH V.; PASANPHAN, WANVIMOL. Water-soluble chitosan conjugated DOTA-bombesin peptide capped gold nanoparticles as a targeted therapeutic agent for prostate cancer. Nanotechnology, Science and Applications, v. 14, p. 69-89, 2021. DOI: 10.2147/NSA.S301942

    Abstract: Introduction: Functionalization of water-soluble chitosan (WSCS) nanocolloids with, gold nanoparticles (AuNPs), and LyslLys3 (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-bombesin 1– 14 (DOTA-BBN) peptide affords an innovative pathway to produce prostate tumor cell-specific nanomedicine agents with potential applications in molecular imaging and therapy. Methods: The preparation involves the production and full characterization of water-soluble chitosan (WSCS), via gamma (γ) rays (80 kGy) irradiation, followed by DOTA-BBN conjugation for subsequent use as an effective template toward the synthesis of tumor cell-specific AuNPs-WSCS-DOTA-BBN. Results: The WSCS-DOTA-BBN polymeric nanoparticles (86 ± 2.03 nm) served multiple roles as reducing and stabilizing agents in the overall template synthesis of tumor cell-targeted AuNPs. The AuNPs capped with WSCS and WSCS-DOTA-BBN exhibited average Au-core diameter of 17 ± 8 nm and 20 ± 7 nm with hydrodynamic diameters of 56 ± 1 and 67± 2 nm, respectively. The AuNPs-WSCS-DOTA-BBN showed optimum in vitro stability in biologically relevant solutions. The targeted AuNPs showed selective affinity toward GRP receptors overexpressed in prostate cancer cells (PC-3 and LNCaP). Discussion: The AuNPs-WSCS-DOTA-BBN displayed cytotoxicity effects against PC-3 and LNCaP cancer cells, with concomitant safety toward the HAECs normal cells. The AuNPs-WSCS-DOTA-BBN showed synergistic targeting toward tumor cells with selective cytotoxicity of AuNPs towards PC-3 and LNCaP cells. Our investigations provide compelling evidence that AuNPs functionalized with WSCS-DOTA-BBN is an innovative nanomedicine approach for use in molecular imaging and therapy of GRP receptor-positive tumors. The template synthesis of AuNPs-WSCS-DOTA-BBN serves as an excellent non-radioactive surrogate for the development of the corresponding 198AuNPs theragnostic nanoradiopharmaceutical for use in cancer diagnosis and therapy.

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  • IPEN-DOC 27817

    ERMAKOV, VIKTOR A.; MARTINS, WELITON S.; WETTER, NIKLAUS U. ; MARQUES, FRANCISCO C.; JIMENEZ-VILLAR, ERNESTO . Localization of light induced in ordered colloidal suspensions: powerful sensing tools. Nanoscale, v. 13, n. 13, p. 6417-6425, 2021. DOI: 10.1039/d0nr08736j

    Abstract: We study the light–matter coupling by Raman scattering in colloidal suspensions composed by core–shell TiO2@Silica (Rutile@Silica) nanoparticles suspended in ethanol and water solutions. Strong enhancement of the Raman signal per particle is observed as [TiO2@Silica] is increased above a threshold, being stronger in ethanol suspensions. Moreover, above this [TiO2@Silica] threshold, the optical transmittance of the ethanol suspension starts to be considerably lower than in water, despite scattering strength being higher in water. These results are attributed to localization of light induced by strong correlation in the scatterers’ position as a consequence of the long-range Coulomb interaction between the TiO2@Silica nanoparticles. Light diffraction in TiO2@Silica suspensions (water and ethanol) shows strong correlation in the scatterers’ position (structure seemingly cubic), being stronger in ethanol than in water (longer-range Coulomb interaction). As a result, we demonstrate in these colloidal suspensions for the first time, to our knowledge, strongly enhanced light–matter coupling through correlation-induced localization with klT much higher than unity and in an ordered colloidal-photonic structure. This strong enhancement of light–matter coupling by localization of light opens an avenue for manufacturing powerful sensing tools.

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  • IPEN-DOC 27816

    AQUINO, SIMONE ; LIMA, JOSE E.A. de; REIS, TATIANA A. dos; CORREA, BENEDITO; BORRELY, SUELI I. . Mycoflora and DNA sequencing analysis of radioresistant fungi isolated from irradiated vehicular air conditioning filters collected in São Paulo, Brazil. Microbiology Research International, v. 9, n. 1, p. 1-15, 2021. DOI: 10.30918/MRI.91.21.011

    Abstract: Fungal bioburdens in filters from car air conditioning systems represent a potential risk of respiratory or pulmonary diseases to both passengers and drivers. The present study demonstrated high fungal contamination in air conditioning filters collected from fifty-seven vehicles from the city of São Paulo, Brazil. The filters samples were irradiated with 10, 15 and 20 kGy gamma ray doses with a cobalt-60 source. The presence of Aspergillus flavus, Penicillium glabrum and Fusarium incarnatum-equiseti remaining after the ionizing treatment with 10 and 15 kGy. The radioresistant pathogenic species was confirmed through genetic sequencing of the ITS, β-tubulin and calmodulin gene rDNA regions. The 20 kGy dose was efficient in inhibiting pathogenic fungi growth in all samples but promoted the fungal decontamination in 79% of the samples. These results and other efforts will enable ionizing radiation to become an important tool in contributing to the recycling of automotive vehicle air filters and in ensuring indoor air quality for both drivers and passengers.

    Palavras-Chave: ionizing radiations; air quality; indoor air pollution; vehicles; air conditioning; fungal diseases; air filters; air cleaning systems

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  • IPEN-DOC 27815

    SOUZA, SAUL H. de; PLAUT, RONALD L.; LIMA, NELSON B. de ; OLIVEIRA, RENE R. de ; PADILHA, ANGELO F.. The occurrence of a peripheral coarse grain zone (PCGZ) in extruded bars of AA 7108. Materials Science Forum, v. 1016, p. 1141-1146, 2021. DOI: 10.4028/www.scientific.net/MSF.1016.1141

    Abstract: Industrial-scale extruded profiles of AA 7108 with a rectangular section (25.60 mm x 15.95 mm) were used in this investigation. Some complementary microstructural analysis techniques, such as polarized light microscopy, EBSD (Electron Backscatter Diffraction) and X-ray diffraction were used to characterize the microstructure, focusing on the PCG zone. It was observed that the extruded profiles presented a totally recrystallized microstructure and a 300 μm layer of peripheral coarse grains. Additionally, the results showed that the PCGZ predominant grain orientation {311} <110> differs from the texture below the PCGZ (Goss and Cube components).

    Palavras-Chave: aluminium alloys; crystallography; microstructure; metallography; extrusion

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  • IPEN-DOC 27814

    GARCIA, CLAUDIO F.; MARANGON, CRISIANE A.; MASSIMINO, LIVIA C.; KLINGBEIL, MARIA F.G. ; MARTINS, VIRGINIA C.A.; PLEPIS, ANA M. de G.. Development of collagen/nanohydroxyapatite scaffolds containing plant extract intended for bone regeneration. Materials Science & Engineering C, v. 123, p. 1-12, 2021. DOI: 10.1016/j.msec.2021.111955

    Abstract: In this study scaffolds of nanohydroxyapatite (nHA) and anionic collagen (C) combined with plant extracts intended for bone tissue repair were developed. Grape seed (P), pomegranate peel (R) and jabuticaba peel (J) extracts were used as collagen crosslinker agents in order to improve the materials properties. All crude extracts were effective against Staphylococcus aureus, but only for CR scaffold inhibition zone was noticed. The extracts acted as crosslinking agents, increasing enzymatic resistance and thermal stability of collagen. The extracts showed cytotoxicity at the concentrations tested, while nHA increased cell viability. The scaffolds presented porosity and pore size appropriate for bone growth. CR, CnHAP, CnHAR and CnHAJ increased the cell viability after 24 h. The combination of collagen, nHA and plant extracts offers a promising strategy to design novel biomaterials for bone tissue regeneration.

    Palavras-Chave: bone tissues; collagen; regeneration; flavonoids

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  • IPEN-DOC 27813

    SILVA, MAIRA V. da; FAJARDO, HUMBERTO V.; RODRIGUES, THENNER S.; SILVA, FELIPE A. e; BERGAMASCHI, VANDERLEI S. ; DIAS, ANDERSON; SIQUEIRA, KISLA P.F.. Synthesis of NiMoO4 ceramics by proteic sol-gel method and investigation of their catalytic properties in hydrogen production. Materials Chemistry and Physics, v. 262, p. 1-10, 2021. DOI: 10.1016/j.matchemphys.2021.124301

    Abstract: A proteic sol-gel route was used in the production of NiMoO4 catalysts, which used edible gelatin as a precursor. The triple helix structure of a protein in contact with identical structures acquires an unfolded form, which favors the interaction of the reactive groups of the gelatin (NH3+ and COO−) with the metallic ions (MoO42− and Ni2+). The synthesized catalysts were thoroughly characterized using techniques such as X-ray diffraction, thermogravimetric and differential thermal analysis, Raman scattering, scanning and transmission electron microscopies, UV–Vis spectroscopy, and colorimetry. The results showed that it is possible to prepare the phase-pure α-NiMoO4 polymorph only at temperatures above 700 °C, while a mixture of the polymorphs α and β were obtained at lower temperatures. The synthesized materials calcined at 300, 500, and 700 °C have their catalytic potentials tested in the ethanol steam reforming reaction aiming the production of hydrogen and presented a good performance. The results indicated that among tested materials, the sample calcined at 700 °C exhibited the highest stability, activity, and best selectivity relative to the product of interest.

    Palavras-Chave: hydrogen production; molybdates; sol-gel process; gelatin; raman spectra

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  • IPEN-DOC 27812

    MACHADO, CARULINE de S.C. ; DONATUS, UYIME ; MILAGRE, MARIANA X. ; ARAUJO, JOAO V. de S. ; VIVEIROS, BARBARA V.G. de ; KLUMPP, RAFAEL E. ; PEREIRA, VICTOR F.; COSTA, ISOLDA . How microstructure affects localized corrosion resistance of stir zone of the AA2198-T8 alloy after friction stir welding. Materials Characterization, v. 174, p. 1-14, 2021. DOI: 10.1016/j.matchar.2021.111025

    Abstract: In this study, the microstructure and corrosion resistance of the stir zone (SZ) of the AA2198-T8 Al-Cu-Li alloy welded by friction stir welding (FSW) were investigated by microscopy, immersion tests and electrochemical techniques such as measurements of open circuit potential variation with time, and scanning vibrating electrode technique (SVET) measurements. A low chloride-containing solution (0.005 mol L−1 NaCl) was employed in the corrosion studies and severe localized corrosion (SLC) was observed in the SZ related to intergranular attack. The results were compared to those of the non-affected areas by FSW, also known as base metal (BM). In the BM, SLC was found and the type of attack related to it was intragranular. In both zones, BM and SZ, SLC was due to precipitates of high electrochemical activity, specifically T1 (Al2CuLi) phase in the BM, whereas TB (Al7Cu4Li) / T2 (Al6CuLi3) in the SZ. Scanning vibrating electrode technique (SVET) analysis was very useful in the study of SLC in the AA2198-T8 alloy showing the development of high anodic current densities at the mouth of the SLC sites.

    Palavras-Chave: electrochemistry; friction welding; stir reactor; corrosion resistance; microstructure

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  • IPEN-DOC 27811

    BAINO, FRANCESCO; FIUME, ELISA; CIAVATTINI, SARA; KARGOZAR, SAEID; BORGES, ROGER; GENOVA, LUIS A. ; MARCHI, JULIANA; VERNE, ENRICA. Biomedical radioactive glasses for brachytherapy. Materials, v. 14, n. 5, p. 1-18, 2021. DOI: 10.3390/ma14051131

    Abstract: The fight against cancer is an old challenge for mankind. Apart from surgery and chemotherapy, which are the most common treatments, use of radiation represents a promising, less invasive strategy that can be performed both from the outside or inside the body. The latter approach, also known as brachytherapy, relies on the use of implantable beta-emitting seeds or microspheres for killing cancer cells. A set of radioactive glasses have been developed for this purpose but their clinical use is still mainly limited to liver cancer. This review paper provides a picture of the biomedical glasses developed and experimented for brachytherapy so far, focusing the discussion on the production methods and current limitations of the available options to their diffusion in clinical practice. Highly-durable neutron-activatable glasses in the yttria-alumina-silica oxide system are typically preferred in order to avoid the potentially-dangerous release of radioisotopes, while the compositional design of degradable glass systems suitable for use in radiotherapy still remains a challenge and would deserve further investigation in the near future.

    Palavras-Chave: neoplasms; therapy; brachytherapy; radioisotopes; microspheres; radioactive materials

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  • IPEN-DOC 27810

    SCAGLIUSI, SANDRA R. ; CARVALHO, ELIZABETH C.L. ; LUGAO, ADEMAR B. . Introduction to the study of mechanical properties of terpolymer PP/EPDM mixtures. Journal of Research Updates in Polymer Science, v. 10, p. 1-8, 2021. DOI: 10.6000/1929-5995.2021.10.1

    Abstract: Thermoplastic elastomers (TPEs), based in PP (Polypropylene) / EPDM (Ethylene Propylene Diene Monomer) have as purpose improving PP resistance and impact, aiming to a more comprehensive use in automotive market, among edifications, construction and packaging sectors, due to their recyclability properties. PP is a commodity, with a high melting point, high mechanical resistance and low density, posing a balance between physical and mechanical properties; in addition, it shows an easy processing, at low cost. In order to minimize this deficiency, EPDM, an impact modifier, can be used. Nevertheless, most of polymeric blends are incompatible and immiscible, i.e., show a mutual and limited solubility and in most of cases, a high interfacial tension. However, there is a relatively low interfacial tension (force which acts on transformation of a continuous structure in a dispersion) between PP and EPDM (approximately 0.3 mN.m-1), reducing the rate of breakup and facilitating the build-up of a continuous structure. This work aims to the study of compatibility of PP and EPDM blends and variation of mechanical properties, emphasizing that many properties of thermoplastic elastomers can be processed according with conventional thermoplastics methods: herein, PP/EPDM blends, 90/10, 80/20, 70/30 and 50/50 were characterized according to: Mechanical essays, Differential Scanning Calorimetry, Thermogravimetric Analyses, Melt Flow Index, Izod Impact Strength and Dynamic mechanical Analyses.

    Palavras-Chave: thermoplastics; elastomers; thermal gravimetric analysis; polymers; compatibility

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  • IPEN-DOC 27809

    CARDOSO, ELIZABETH C.L. ; PARRA, DUCLERC F. ; SCAGLIUSI, SANDRA R. ; KOMATSU, L.G.H. ; LUGAO, ADEMAR B. . Effect of ionizing radiation applied to PLA used as compatibilizing agent in reinforced eGG shell PBAT/PLA bio-based composites. Journal of Research Updates in Polymer Science, v. 10, p. 27-33, 2021. DOI: 10.6000/1929-5995.2021.10.4

    Abstract: Bio-filler from eggshells as reinforcement of bio-based polymers are based on their benefits as adequate strength and stiffness, besides friendly, degradable and renewable environment. Eggshell is an agricultural waste considered as garbage, contributing to pollution; nevertheless, it can be transformed into bio-calcium carbonate, acquiring new values. As biodegradable polymers, there were chosen PLA (poly-lactic-acid) and PBAT (butylene adipate co-terephthalate), thermoplastics capable to be processed via conventional methods. PLA is a linear, aliphatic thermoplastic polyester, high in strength and modulus, but brittle. PBAT is a synthetic polymer, very flexible, based on fossil resources with high elongation at break, but low strength. It will be required the use of compatibilizers, for reducing interfacial tension exhibited by PLA/PBAT immiscible blend, considering their extreme glass transition temperatures: 62 ° C for PLA and – 30 ° C for PBAT. Herein it was used ionizing radiation for inducing compatibilization by free radicals, improving dispersion and adhesion of blend phases, without using chemical additives, at room temperature. PLA, acting as compatibilizer, was previously e-beam and gamma radiated, at 150 kGy. PBAT/PLA 50/50 blend with 15 phr of biofiller from avian eggs 125 μm particle size and both compatibilizers were homogeneized in a co-rotating twin-screw extruder, within a temperature profile 120 to 145 ° C, from hopper to die. Characterization involved: Differential Scanning Calorimeter, Thermogravimetric Analyses, Fourier Transform Infrared Spectroscopy, Wide Angle X-Ray Diffraction, Tensile Strength and Elongation at Break.

    Palavras-Chave: lactic acid; ionizing radiations; eggs; polymers; thermal gravimetric analysis

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  • IPEN-DOC 27808

    VILLANI, D. ; RODRIGUES JUNIOR, O. ; MASCARENHAS, Y.M.; CAMPOS, L.L. . Study on electronic equilibrium of 137Cs gamma radiation for 3D printed phantoms using OSL dosimetry. Journal of Physics: Conference Series, v. 1826, p. 1-6, 2021. DOI: 10.1088/1742-6596/1826/1/012057

    Abstract: With the popularization of 3D printing technologies, it is now possible to develop patient specific simulators and various other accessories using this technology in medical physics and dosimetry. This work aims to evaluate the electronic equilibrium of 3D printed phantoms using PLA and ABS filaments compared to PMMA for 137Cs gamma rays using OSL dosimetry. A Landauer microStar ii commercial OSL system was commissioned and it was used nanoDot dosimeters. Phantom plates with 2.5, 3.0 and 5.0 mm thickness were used to obtain electronic equilibrium for 137Cs gamma rays. Measurements were compared with PMMA measurements at standard conditions. Results show that measurements with ABS and PLA thicknesses of 2.5 and 3.0 mm presents dosimetry results within irradiation uncertainty. More accuracy is obtained using 3.0 mm for both PLA and ABS phantoms, with differences in less than 0.5%. It can be concluded that PLA and ABS 3D phantom plates has similar properties of PMMA for 137Cs gamma rays dosimetry and can be used for developing dosimetry accessories for this energy photon beam.

    Palavras-Chave: phantoms; 3d printing; gamma radiation; photoluminescence; dosimetry

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  • IPEN-DOC 27807

    SILVA, NATALIA F. ; SILVA, TIAGO F.; CASTRO, MAYSA C. ; LUZ, HUGO N. da; CALDAS, LINDA V.E. . Garfield++ simulation of a TH-GEM based detector for standard mammography beam dosimetry. Journal of Physics: Conference Series, v. 1826, p. 1-6, 2021. DOI: 10.1088/1742-6596/1826/1/012046

    Abstract: The TH-GEM based detector is a robust, simple to manufacture, high-gain gaseous electron multiplier. Its operation is based on a standard printed circuit board (PCB) coated on both sides by metallic material, perforated in a millimeter pattern, and immersed in gas. In order to study the feasibility of using TH-GEM type detectors in dosimetric applications for standard mammography beams, a prototype with adequate dimensions and materials was produced. The present work encompasses the calculations of electric fields by the Gmsh and Elmer software packages and the avalanche simulation using Garfield++ library of a TH-GEM detector filled with Ar/CO2 mixture at atmospheric pressure.

    Palavras-Chave: mammary glands; radiation detectors; computer codes; dosimetry; computerized simulation; computer calculations; standards; charge transport

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  • IPEN-DOC 27806

    POLO, I.O. ; CALDAS, L.V.E. . Fading estimation of SOL-GEL α-Al2O3 detectors. Journal of Physics: Conference Series, v. 1826, p. 1-6, 2021. DOI: 10.1088/1742-6596/1826/1/012045

    Abstract: The OSL and the TL techniques are used in several fields of radiation dosimetry. The dosimeters are affected by a signal loss in the time between the irradiation and readout (fading). This undesirable characteristic can cause an underestimation of the irradiation dose. The fading estimation of SOL-GEL α-Al2O3 with several different concentrations of impurities is reported. The thermal fading and the light-induced fading of the SOL-GEL α-Al2O3 detectors were estimated. Furthermore, the exponential equations used to interpolate the experimental results were presented.

    Palavras-Chave: photoluminescence; sol-gel process; aluminium oxides; dosimetry

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  • IPEN-DOC 27805

    KUAHARA, L.T. ; MARTINS, E.W. ; POTIENS, M.P.A. . Development of an “in situ” calibration methodology to activity meters. Journal of Physics: Conference Series, v. 1826, p. 1-5, 2021. DOI: 10.1088/1742-6596/1826/1/012009

    Abstract: The performance of a safety and efficient practice of a nuclear medicine service depends, among other factors, on a complete quality control program, especially in the case of the radionuclide activity measuring instrument, the activimeter. Several factors may influence the accuracy of the measurements performed with an activimeter, and the largest sources of errors are related to the types of containers that contain radiopharmaceuticals (eg, thickness, size and volume). A complete quality control program should include the calibration of all measurement instruments used in the procedure. However, in Brazil, the actual standard that establishes the requirements of radiological protection for nuclear medicine services (NMS), does not include the calibration of the activimeter. Considering that these instruments, for various reasons, are difficult to remove for sending to a Calibration Service, the purpose of this work is to develop a methodology for activimeter calibration that can be applied "in situ" to the most used radiopharmaceutical, 99mTc.

    Palavras-Chave: activity meters; calibration; legislation; quality control; radiation protection; technetium 99

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  • IPEN-DOC 27804

    SANTOS, WILLIAM S. ; NEVES, LUCIO P.; PERINI, ANA P.; SANTOS, CARLA J.; BELINATO, WALMIR; SILVA, ROGERIO M.V.; SOARES, MARIA R.; VALERIANO, CAIO C.; CALDAS, LINDA V.E. . Computational modelling of cervix radiation procedure using a virtual anthropomorphic phantom and the MCNPX code. Journal of Physics: Conference Series, v. 1826, p. 1-8, 2021. DOI: 10.1088/1742-6596/1826/1/012040

    Abstract: There is a serious, and growing concern about the increased risk of the emergence of a secondary cancer, radio-induced, associated with radiotherapy treatments. To assess the radiation doses to organs outside the target volume, in this work, several computational exposure scenarios were modelled, based on Monte Carlo simulation (MCNPX code). A Varian 2100c accelerator, and a female virtual anthropomorphic phantom were used, in a simulated treatment of cervical cancer. The determination of the dispersed dose would be important for assessing the risk in different organs or tissues. Four treatment fields were applied, varying the gantry angle. It was possible to observe that the conversion factors for equivalent dose were higher for the AP projection. For the RLAT and LLAT projections, the results were similar, fact that may be attributed to the symmetrical distributions of the organs in relation to the radiation source. The results presented in this work showed that the computational exposure scenario provides a versatile and accurate tool to estimate in a ready way the absorbed doses during a cervical treatment.

    Palavras-Chave: absorbed radiation doses; animal tissues; computerized simulation; dosimetry; monte carlo method; organs; phantoms; radiotherapy; uterus

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  • IPEN-DOC 27803

    CABRAL, T.S.; LARANJEIRA, A.S.; POTIENS, M.P.A. ; SOARES, C.M.A.; KHOURY, H.; SAITO, V.; DAVID, M.; VIDAL, L.C.; PIRES, M.A.. Comparison of calibration of surface contamination monitors with Brazilian Network - 2018/2019. Journal of Physics: Conference Series, v. 1826, p. 1-6, 2021. DOI: 10.1088/1742-6596/1826/1/012039

    Abstract: This work reports the results obtained from the comparison involving 7 laboratories in Brazil. This exercise is about the calibration service of surface contamination monitors. The monitor has been calibrated to BS ISO 7503-3, the calibration factor in terms of surface emission rate. The comparison was conducted by the Brazilian National Laboratory of Ionizing Radiation Metrology (LNMRI / IRD) from October 2018 to July 2019. The extensive sources used were 14C, 137Cs, 60Co, 90Sr/90Y, 36Cl and 241Am. The result of this proficiency test was excellent and proved the calibration capacity of the Brazilian network in the calibration service for surface contamination monitors.

    Palavras-Chave: calibration standards; interlaboratory comparisons; iso; radiation protection; radiation sources; surface contamination monitors

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  • IPEN-DOC 27802

    VILLANI, D. ; SAVI, M. ; ANDRADE, M.A.B.; CAMPOS, L.L. ; POTIENS, M.P.A. . Characterization of ABS + W and ABS + Bi 3D printing filaments attenuation for different photon beams. Journal of Physics: Conference Series, v. 1826, p. 1-8, 2021. DOI: 10.1088/1742-6596/1826/1/012037

    Abstract: 3D printing techniques and materials have become widely available in the last couple of decades and remains a hot topic of study as new materials can lead to new applications. This study aims to evaluate the attenuation behaviour of GMASS over photon beams ranging from 29.7 up to 661.7keV, comparing with pure ABS and using theoretical data of pure lead as reference. It was used the transmission method to obtain experimental attenuation coefficients to all materials and theoretical data. HVL and TVL calculations were also performed. Results show that ABS+W has higher attenuation than ABS+Bi and pure ABS. Using the lead theoretical reference data it can be concluded that although ABS+Bi and ABS+W attenuates less than pure lead, the 3D printing filaments can be used to create shielding tolls depending on radiation energy and application.

    Palavras-Chave: attenuation; cesium 137; dosimetry; energy dependence; filaments; photon beams; polymers; radiations; shielding

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ESTE TEXTO "AJUDA" ESTÁ SUJEITO A ATUALIZAÇÕES CONSTANTES, A MEDIDA QUE NOVAS FUNCIONALIDADES E RECURSOS DE BUSCA FOREM SENDO DESENVOLVIDOS PELAS EQUIPES DA BIBLIOTECA E DA INFORMÁTICA.

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.