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  • IPEN-DOC 29558

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

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

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  • IPEN-DOC 29557

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

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

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  • IPEN-DOC 29556

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

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

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  • IPEN-DOC 29555

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

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

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  • IPEN-DOC 29554

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

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

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  • IPEN-DOC 29553

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

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

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  • IPEN-DOC 29552

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

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

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  • IPEN-DOC 29551

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

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

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  • IPEN-DOC 29521

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

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

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  • IPEN-DOC 29520

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

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

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  • IPEN-DOC 29519

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

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

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  • IPEN-DOC 29518

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

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

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  • IPEN-DOC 29517

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

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

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  • IPEN-DOC 29516

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

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

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  • IPEN-DOC 29515

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

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

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  • IPEN-DOC 29514

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

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

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  • IPEN-DOC 29513

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

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

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  • IPEN-DOC 29512

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

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

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  • IPEN-DOC 29511

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

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

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  • IPEN-DOC 29510

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

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

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  • IPEN-DOC 29509

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

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

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  • IPEN-DOC 29508

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

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

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  • IPEN-DOC 29507

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

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

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  • IPEN-DOC 29506

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

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

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  • IPEN-DOC 29505

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

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

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  • IPEN-DOC 29504

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

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

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  • IPEN-DOC 29502

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

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

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  • IPEN-DOC 29500

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

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

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  • IPEN-DOC 29499

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

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

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  • IPEN-DOC 29498

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

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

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  • IPEN-DOC 29497

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

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

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  • IPEN-DOC 29496

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

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

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  • IPEN-DOC 29495

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

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

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  • IPEN-DOC 29494

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

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

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  • IPEN-DOC 29493

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

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

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  • IPEN-DOC 29492

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

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

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  • IPEN-DOC 29491

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

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

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  • IPEN-DOC 29471

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

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

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  • IPEN-DOC 29330

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

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

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  • IPEN-DOC 29321

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

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

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  • IPEN-DOC 29314

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

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  • IPEN-DOC 29313

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

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

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  • IPEN-DOC 29312

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

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

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  • IPEN-DOC 29290

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

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

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  • IPEN-DOC 29289

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

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

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  • IPEN-DOC 29288

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

    Abstract: Background: Dysprosium oxide (Dy2O3) gathers a set of profitable properties with a wide range of applications, including energy and astronomy. Particular characteristics directly influence the formation and features of materials by colloidal processing. The main purpose of this paper is to carry out a powder characterization of Dy2O3particles. The findings reported are worthwhile parameters to advance in the formulation of new smart materials for radiation dosimetry. Methods: Dy2O3 powders were characterized by XRD, PCS, SEM, pynometric density (ρ), FTIR, ICP, EPR, and zeta potential (ζ). Results: The powdered samples exhibited as main features a cubic C-type structure following the RE-polymorphic diagram, a mean particle size distribution with d50 of 389nm, and pynometric density of 7.94g.cm-3. The EPR spectra revealed three distinct peaks, p1, p2, and p3, with the following g values: 2.3121, 2.1565, and 2.1146. In addition, the nanoparticles presented high stability at pH 5.5 and a ζ-value of |49.7|mV. Conclusion: The powder characterization of Dy2O3 powders was reported. The results achieved in this study may be considered worthwhile parameters to advance in the formulation of Dy2O3- based materials for radiation dosimetry.

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  • IPEN-DOC 29215

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

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

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  • IPEN-DOC 29214

    OLIVEIRA, MARA C.L. de; SILVA, REJANE M.P. da ; SOUTO, RICARDO M.; ANTUNES, RENATO A.. Investigating local corrosion processes of magnesium alloys with scanning probe electrochemical techniques: a review. Journal of Magnesium and Alloys, v. 10, n. 11, p. 2997-3030, 2022. DOI: 10.1016/j.jma.2022.09.024

    Abstract: The study of corrosion of magnesium and its alloys has emerged a hot topic in the applications of lightweight structural materials. The inherently high electrochemical activity of bare magnesium surfaces still lacks a convincing mechanism to describe the observed experimental characteristics, and it has prompted the development of various types of protective coatings with the aim of slowing metal dissolution. In recent years, new instruments and techniques have been developed to study with spatial resolution the local corrosion processes that occur in metallic materials in general, and for magnesium and its alloys in particular, both for bare surfaces and coated. Scanning microelectrochemical techniques, such as local electrochemical impedance spectroscopy (LEIS), scanning electrochemical microscopy (SECM), scanning vibrating electrode technique (SVET), scanning ion-selective electrode technique (SIET) and scanning Kelvin probe (SKP) can provide information about the local electrochemical activity of metallic surfaces. In the present work, the applications of these techniques in corrosion studies of magnesium and its alloys are reviewed. Assessment of corrosion mechanisms, barrier properties of conventional coatings and active corrosion behavior of self-healing coatings are examined. Limitations and future developments in this area are discussed.

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  • IPEN-DOC 29213

    PRADO, MARILIZA C.O. ; NWIZU, NGOZI N.; PATEL, SHALIZEH A.; STRECKFUS, CHARLES F.; ZEZELL, DENISE M. ; BARROS, JULIANA. Thermal damage and excision time of micro and super pulsed diode lasers: a comparative ex vivo analysis. Clinical and Experimental Dental Research, v. 8, n. 6, p. 1655-1663, 2022. DOI: 10.1002/cre2.670

    Abstract: Objectives: The primary aim of this ex vivo study was to evaluate thermal damage and cutting efficiency of micro and super pulsed diode lasers. The secondary aim was to suggest a guideline to perform simple surgical excisions adequate for histopathological evaluation. Material and Methods: Ten groups of 10 specimens of pig tongues were excised using a blade (G1), a micro pulsed (G2–G9), and a super pulsed diode (G10) lasers. Different output power, pulse duration, pulse interval, and duty cycle were tested. Quantitative measures of thermal damage and excision times were recorded. Statistical analysis was performed at a significance level of 5%. Results: The control group (G1) presented no thermal damage. Within the laser groups (G2–G10), no statistically significant differences in depth of thermal damage (μm) were noted. G3 showed significantly less area of thermal damage (mm2) when compared with G7 and G9 (p < .05). The median excision time of the control group and super pulsed diode laser group were significantly lower (p < .001) than the micro pulsed diode laser groups. Conclusions: The cutting efficiency of the super pulsed diode laser is comparable to traditional blade, and with appropriate parameters, these lasers can produce predictable surgical outcomes with less collateral damage.

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  • IPEN-DOC 29212

    NASCIMENTO, JOAO P.S.; MARTINS, ANTONIO J.; BEZERRA, RITA de C.F.; BERTOLDO, GABRIELA M.; OLIVEIRA, ALCINEIA C.; BEZERRA, JOAO R.; ARAUJO, RINALDO S.; LANG, ROSSANO; OTUBO, LARISSA ; RODRIGUEZ-AGUADO, E.; RODRIGUEZ-CASTELLON, E.. Designed synthesis of nanostructured ZrO2 as active support for glycerol valorization reaction. Ceramics International, v. 49, n. 2, p. 1764-1778, 2023. DOI: 10.1016/j.ceramint.2022.09.140

    Abstract: Designed synthesis of nanostructured ZrO2 as support for glycerol valorization reaction was investigated. The nanocasting route was used to obtain the ZrO2 support possessing well-dispersed Cu and Zn nanoparticles. The solids were fully characterized by High-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Electron paramagnetic resonance (EPR), N2-physisorption isotherms, Temperature-programmed desorption of ammonia (NH3-TPD), Scanning electron microscopy coupled to energy dispersive spectroscopy (SEM-EDS) and Fourier transform infrared (FTIR) spectroscopy measurements. The resultant CuZn/ZrO2 catalyst presented here was distinguished by its unique mesostructured features and defective sites formation. The promotional effect of Cu nanoparticles on the activity illustrated that the formation of active acid sites of medium to strong strength can be modulated by adding a second metal to the catalyst. All these properties provided active solids for acetalization of glycerol with aldehydes and ketones due to the interaction between the active centers and the nanostructured support. Density functional theory (DFT) calculation showed the most favorable mechanistic route of low energy for biofuel additives production.

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  • IPEN-DOC 29211

    ARAUJO, ERIKA M. dos S.; VIDAL, CRISTINA de M.P.; FREITAS, ANDERSON Z. de ; WETTER, NIKLAUS U. ; MATOS, ADRIANA B.. Characterization of sound enamel and natural white spot lesions / Caracterização de esmalte hígido e lesões de mancha branca naturais. Brazilian Dental Science, v. 25, n. 4, p. 1-10, 2022. DOI: 10.4322/bds.2022.e3488

    Abstract: Objective: To compare optical, morphological, chemical, and physical aspects of the sound enamel and white spot lesions (WSL) classified as ICDAS 2. Material and Methods: Seventeen human molars with one surface presenting WSL and a sound surface (2 x 2 mm window) were characterized by Quantitative light-induced fluorescence (QLF®), Optical coherence tomography (OCT), microhardness, and Raman spectroscopy. The ANOVA and Tukey’s test were used at 5% significance level. Results: The QLF comparison between distinct substrates yielded decreased ΔQ (integrated fluorescence loss) of -15,37%mm2 and -11,68% ΔF (fluorescence loss) for WSL. The OCT detected mean lesion depth of 174,43 μm. ANOVA could not detect differences in the optical attenuation coefficient between the substrates (p>0.05). Lower microhardness measures were observed in WSL than on sound enamel (p<0.05). The Raman spectra showed four vibrational phosphate bands (v1, v2, v3, v4), where the highest peak was at 960.3 cm-1 (v1) for both substrates. However, a 40% decrease in phosphate (v1) was detected in WSL. The peak at 1071 cm-1 was higher for sound enamel, indicating the presence of a phosphate band instead of the B-type carbonate. The spectra showed higher intensity of the organic composition at 1295 cm-1 and 1450 cm-1 for WSL. Conclusion: Non-invasive QLF, OCT and Raman spectroscopy were able to distinguish differences in fluorescence, optical properties, and organic/inorganic components, respectively, between sound enamel and WSL, validated by the destructive microhardness analysis.

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  • IPEN-DOC 29146

    AYLLON, RAFAELLA M. ; SEMMLER, RENATO ; SANTOS, DENISE M. dos; FARIAS, LUCIANA A.; SILVA, PAULO S.C. . Social representations of ETEC teachers about nuclear technology / Representações sociais de professores de ETEC sobre tecnologia nuclear. Revista Ciências & Ideias, v. 13, n. 2, p. 157-168, 2022. DOI: 10.22407/2176-1477/2022.v13i2.1993

    Abstract: Este artigo apresenta um estudo que visa compreender a representação social da tecnologia nuclear feita por um grupo de professores e coordenadores de Escolas Técnicas Públicas (ETEC) do estado de São Paulo. Após este grupo ter participado em palestras ministradas por pesquisadores do Instituto de Pesquisas Energéticas e Nucleares (IPEN), que incluíram visitas ao Instituto e ao Reator Nuclear de Pesquisa IEA-R1. O estudo foi realizado por meio de questionários semiestruturados. Os resultados demonstraram que, para a maioria dos participantes, a representação social da tecnologia nuclear mudou positivamente após um evento de três dias, mesmo que eles já tivessem algum conhecimento sobre o assunto. Também foi possível detectar alguns erros conceituais e corrigi-los, evidenciando que o contato técnico mais próximo foi fundamental para essa mudança.

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  • IPEN-DOC 29145

    BOIANI, N.F. ; TOMINAGA, F.K. ; BORRELY, S.I. . Toxicity removal of pharmaceuticals mixtures through electron beam irradiation. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-11, 2022. DOI: 10.15392/2319-0612.2022.1838

    Abstract: Contamination of the aquatic environment by pharmaceuticals is becoming a global phenomenon of growing concern. Pharmaceuticals are partially metabolized, resulting in the excretion and release of residual into sewage, unaltered or metabolites. The wastewater treatment plants are not designed to eliminate these compounds, leading the residues into the aquatic environment. Besides, pharmaceuticals are not detected individually but as a complex mixture. Advanced oxidative processes have been applied as an alternative or complement to conventional sewage treatment processes, aiming the degradation and removal of toxic pollutants. The objective of this study was to evaluate the toxicity removal of mixtures of pharmaceuticals subjected to electron beam treatment. The aqueous solutions of each pharmaceutical were diluted in ultra-pure water and prepared in three pharmaceuticals combinations: Propranolol + Fluoxetine + Sulfadiazine; Propranolol + Fluoxetine + Diclofenac; Acetylsalicylic acid + Fluoxetine + Metformin). Electron Beam Accelerator was applied for the irradiations and the absorbed doses were 2.5-5.0 kGy. Acute toxicity tests with Daphnia similis were performed to evaluate the toxicity, before and after irradiation.. The data analyzed showed toxicity removal efficiency around 80% for the mixture of Propranolol, Fluoxetine and Diclofenac; 75% for the mixture of Propranolol, Fluoxetine and Sulfadiazine; and 30% for the mixture of Acetylsalicylic acid, Fluoxetine and Metformin. According to the literature, this is a viable technology for the removal of toxicity from pharmaceuticals, and the results demonstrated the potential of electron beam irradiation in reducing the toxicity of pharmaceutical from different classes.

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  • IPEN-DOC 29144

    NASCIMENTO, G.G. ; CAMPOS, V.P. ; CAMPOS, L.L. . Characterization and calibration of thermoluminescent dosimeters of LiF:Mg, Ti in the quantity Hp(0.07). Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-6, 2022. DOI: 10.15392/2319-0612.2022.1786

    Abstract: The extremity dosimeters are devices used to quantifying the radiation dose that the occupationally exposed individual receives in specific regions of the body during the work time. Dosimeter calibration is essential so that the dosimeter response is equivalent to the received dose. Tests such as batch homogeneity and lower detection limit are part of the dosimeter calibration process. The rod phantom simulates the region of interest regarding the interaction with radiation and the scattered dose. The extremity dosimeters used were the LiF:Mg,Ti thermoluminescent dosimeters.

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  • IPEN-DOC 29143

    COSTA, A.F.; GOMES, D.M.C.; MUNITA, C.S. ; BARIA, R. ; TIZUKA, M.; KIPNIS, R.; WATANABE, S.; CHUBACI, J.F.D.. Nuclear and non-nuclear analytical techniques applied to pre-colonial archaeological ceramics from the upper Madeira River/Brazil (940 to 760 B.P). Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-19, 2022. DOI: 10.15392/2319-0612.2022.1889

    Abstract: This article presents the results of applying three archaeometric techniques in archaeological ceramics from the upper river Madeira region in Amazonia. The first consists of the nuclear technique, neutron activation analysis (INAA), to identify the trace elements of the clay sources used in the production of the vessels. The second, non-nuclear X-ray diffraction (XRD), was used to characterise the mineral phases of each clay source. The third technique, electron paramagnetic resonance spectroscopy (EPR), estimated burning temperature related to the production stage of the artefacts. This approach made it possible to understand technological choices linked to selecting specific clay sources. The results suggest that different indigenous groups that inhabited the region between 940 and 760 B.P selected three clay sources to produce their vessels.

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  • IPEN-DOC 29142

    FULLE, F.N. ; SABUNDJIAN, G. . Comparison of 18F-FDG, 68Ga-PSMA-11 and 18F-PSMA-1007 in PET for prostate cancer. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-11, 2022. DOI: 10.15392/2319-0612.2022.2012

    Abstract: Prostate cancer is the second most incident neoplasm in men, except for non-melanoma skin cancer, and has the second highest mortality rate in Brazil. Early diagnosis increases the chances of cure and enables a less aggressive treatment for the patient. Nuclear Medicine presents effective alternatives for prostate cancer diagnosis, such as Positron Emission Tomography (PET) or PET and Computed Tomography (PET/CT) imaging. The aim of this study is to compare the advantages and disadvantages of the radiopharmaceuticals 18F-FDG, 68Ga-PSMA-11 and 18F-PSMA-1007 used for PET or PET/CT in the diagnosis of this type of cancer. Compared to 18F-FDG, 68Ga-PSMA-11 has some advantages such as its availability by means of generators, the independent production of a cyclotron facility and its theranostic potential. The disadvantages compared to 18F-FDG are the scalability of 18F-FDG production compared to limited generator production. Despite its favorable characteristics, the radiopharmaceutical 18F-FDG has limitations in the diagnosis of some types of tumors, such as prostate cancer. The recently studied radiopharmaceutical 18F-PSMA-1007 has shown potential in the identification of small lesions in cases of prostate cancer and local recurrence. All the favorable and unfavorable aspects of these three radiopharmaceuticals are presented in this work.

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  • IPEN-DOC 29141

    SOUZA, A.P.S. ; OLIVEIRA, L.P. de ; GENEZINI, F.A. ; SANTOS, A. dos . Simulating Araponga: the high-resolution diffractometer of Brazilian Multipurpose Reactor. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-10, 2022. DOI: 10.15392/2319-0612.2022.1861

    Abstract: The Brazilian Multipurpose Reactor (RMB) is a fundamental project that aims to turn Brazil into a self-sufficient country in the production of radioisotopes and radiopharmaceuticals to supply the Unified Health System (SUS) as much as the private institutions. In addition, the RMB project describes other applications as irradiation and testing of nuclear fuels and structural material analysis, for instance. There are many techniques in the project to study structural aspects of materials, where neutron diffraction represents one of the priorities for implementation. This technique will take place mainly on two diffractometers on Thermal Neutron Guide 1 (TG1), namely Araponga, a high-resolution diffractometer, and Flautim, a high-intensity diffractometer. In this work, we study the performance of the Araponga diffractometer through McStas simulations with input produced by the MCNP code of the RMB core. We investigate the neutron flux values considering a state-of-art high-resolution diffractometer, and the results are promising since some simulated scenarios present values compatible with high-intensity devices.

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  • IPEN-DOC 29140

    BARIA, R. ; WATANABE, S.; MUNITA, C.S. ; SILVA, P.S.C. ; TATUMI, S.. Levels of thorium, uranium and potassium in Brazilian geological sediment determined by gamma-ray spectroscopy and instrumental neutron activation analysis. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-13, 2022. DOI: 10.15392/2319-0612.2022.1984

    Abstract: The Brazilian coast of the terrace contains a wealth of evidence that can be used to explain the evolution of the coastline over the past 120k years. These studies include marine sediment geochronology based on dosimetry dating methods, in particular thermoluminescence. To determine the age of the terrace using luminescence dosimetry methods, it is necessary to decide on the exact mass fractions of 238U, 232Th, and 40K. These mass fraction values are used to calculate the annual dose rate of ionized radiation. In this context, in the present work, we studied eight marine sediment samples collected in the city of São Vicente on the coast of São Paulo state, Brazil, and determined the mass fractions of elements 238U, 232Th, and 40K by instrumental neutron activation analysis (INAA) and γ-ray spectroscopy. Linear regression mathematical methods are used to evaluate analytical methods accuracy. The results show a good correlation with a R2 value of more than 0.71. Therefore, it is possible to calculate the resulting mass fraction, calculate the dose rates of these sediments, and contribute to their date.

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  • IPEN-DOC 29139

    NISTI, M.B. ; NERY, A.D. ; SAUEIA, C.H.R. ; CAVALCANTE, F. . Assessment of natural radioactivity in bottled mineral water from Brazil. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-15, 2022. DOI: 10.15392/2319-0612.2022.1795

    Abstract: The approach taken in the WHO Guidelines for controlling radiological hazards in public water supplies has two stages. The first is an initial screening for gross alpha and beta activity to determine whether the activity concentrations are below levels at which no further action is required; and if these screening levels are exceeded, investigation of the concentration of individual radionuclides and comparison with specific guidance levels. Mineral water is obtained directly from natural sources or by extracting groundwater, it is characterized by the quantity of mineral salts, trace elements and other constituents. The bottled water industry is present in the major regions of the world, and the population consumption has increased every year in Brazil and world, also increasing new mineral water mining sites, so it is necessary to constantly check the amount of radioactivity in mineral water. The aim of this study is to quantify the concentration of the natural radionuclides in the bottled mineral water consumed in São Paulo city. The bottled mineral water samples were purchased in a supermarket in São Paulo, with 23 different brands. The determination of gross alpha and beta activity concentration in bottled mineral water by Liquid Scintillation Counting measurement was performed using a 1220 Quantulus™ Ultra Low-Level Liquid Scintillation Spectrometer. The natural radionuclides (226Ra, 228Ra, 210Pb and 40K) were measured by gamma spectrometry, using an HPGe detector. The results obtained in this study can be used for a database on bottled mineral water radioactivity from Brazil.

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  • IPEN-DOC 29138

    SILVA, F.F.A. da ; SANTOS, S.N. dos ; PEREIRA, J.P.M. ; GUSHIKEN JUNIOR, D.S. ; CARNEIRO, M.A.P. ; NASCIMENTO, I.C.C.; ULRICH, A.H.; BERNARDES, E.S. . Selection of aptamers against the Jagged-1 protein. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-7, 2022. DOI: 10.15392/2319-0612.2022.1933

    Abstract: The breast cancer is one of the biggest public health problems in the world, being the main female type of cancer that affects the population. The Jagged-1 protein plays an important role in the biology and development of cancer, influencing angiogenesis, growth of neoplastic cells, tumor stem cells, epithelial mesenchymal transition, metastatic processes and resistance to therapies in various types of cancer. In this project, our aim was to select an aptamer for JAG1 ligand using an aptamer library that could be used as a radiopharmaceutical for PET/SPECT/CT diagnosis of tumors that express JAG1. Our work showed that MDA-MB-231-JAG1 cells overexpress more mRNA and JAG1 protein than control cells (MDA-MB-231-Control). We also selected aptamers with high affinity for MDA-MB-231-JAG1 cells that could be a useful tool for the development of new radiopharmaceuticals for the diagnosis and treatment of tumors that overexpress JAG1.

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  • IPEN-DOC 29137

    ANDRADE, M.V. ; VICENTE, R. . Precautionary and preventive measures in Brazilian law applied to radioactive waste management. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-17, 2022. DOI: 10.15392/2319-0612.2022.1899

    Abstract: Nuclear technologies and radiation have offered technological and scientific growth nowadays, but there is a frequent paradox in this. While these technologies substantially increase the quality of human life, they also produce radioactive waste, which, when not properly managed, can generate risks that threaten to harm the environment and health. As a result, in risk management of radioactive waste, decision-making processes need to be guided by a framework of principles, including the precautionary and preventive principles. For this reason, the present work proposes to develop a legal analysis on radioactive waste risk management using the principles of precaution and prevention. These principles have similarities, but it is the differences in their structure that deserve to be highlighted, which is discussed and exemplified throughout this work. Furthermore, national and international experience in environmental damage has taught us that an identification and assessment of risk is necessary, because if preventive measures are not taken radioactive waste can be dispersed and harm the environment. When it comes to assessing the risk of radioactive waste, one of the precautionary measures is the application of a conservative stance in modelling scenarios, as there are still uncertain risks. Therefore, comprehending the different circumstances surrounding precautionary and preventive measures and having effective information about risk is essential for successful risk management.

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  • IPEN-DOC 29136

    SOUZA, D.C.B.; VICENTE, R. ; SA, L.V.; SILVA, E.H.; OLIVEIRA, M.V.L.; CIDRAL, M.E.V.; FARIA, C.R.; CAMILO, N.F.. Dose estimation in abdominal CT scans using CT-EXPO software. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-11, 2022. DOI: 10.15392/2319-0612.2022.2012

    Abstract: The application of ionizing radiation in diagnostic medicine has increased worldwide in the last decades. Computed Tomography (CT) is the main radiological procedure that contributes to the increase of the collective dose in the population. The aim of this study was to estimate the doses received by patients undergoing CT scans in a public hospital in Santa Catarina - Brazil, employing data from the DICOM header and utilizing the CT-Expo V. 2.7 software. The data were selected from 45 abdominal CT scans consisting of two series: pre-contrast and one post-contrast intravenous, of adult patients performed in December 2020. The spreadsheets with the data extracted from the DICOM headers were provided by the Santa Catarina Telemedicine System (STT). The effective dose and organ doses were calculated by CTDIvol and DLP values using the software. Overall, the organs that showed the higher equivalent doses were the kidneys (19.5 mSv), spleen (18.5 mSv), stomach (18.9 mSv), and liver (18.1 mSv). The estimated effective doses were 7.31 and 8.41 mSv, for non-contrast and contrast-enhanced examinations. The use of software such as CT-Expo can support the estimation of effective doses received by patients through the information extracted from the DICOM header. The presented methodology can be a useful tool to retrospectively estimate the doses in CT services in Brazil.

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  • IPEN-DOC 29135

    GAETA, N.C.; CARVALHO, D.U.O.G.; ALEMAN, M.A.R.; CARVALHO, J.S.; CEDRAZ, P.P.; ULRICH, J.C. ; JOVANE, L.; GREGORY, L.; SCAPIN, M.A. . Quantitative analysis of minor and trace elements in blood serum of dairy cattle (Bos taurus) by WDXRF. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-10, 2022. DOI: 10.15392/2319-0612.2022.1911

    Abstract: Assessment of heavy metal content in biological fluids is essential to determine human and animal health due to exposure to contaminated environments, food and water. WDXRF is a non-destructive method that involves no chemical treatments. It is possible to perform fast chemical analysis without producing hazardous waste and uses a small sample volume (± 50 μL), which is helpful for veterinary usage. Therefore, this work aimed to implement an alternative method for minor and trace elements in blood serum samples of dairy cattle (Bos taurus) using WDXRF. It was implemented to determine Al, Cr, Co, Fe, Cu, and As. The method was evaluated by comparing WDXRF and ICP-OES results of a set of 14 blood serum samples of dairy cattle using principal component analysis (PCA). Results of WDXRF and ICP-OES were statistically equivalent to all analyzed elements, except for Fe and Al, which were still comparable. WDXRF proved to be a suitable alternative methodology for heavy metal detection in animal blood serum samples due to the low sample volume. The results of this study enable a new and fast method for veterinary internal medicine, which detects elevated levels of toxic elements in animal blood samples to ensure the correct protocols to prevent the animal's death.

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  • IPEN-DOC 29134

    PASCOALINO, K. ; CAMARGO, F. ; GONCALVES, J.A.C. ; BUENO, C.C. . Measurement of the insensitive surface layer thickness of a PIN photodiode based on alpha-particle spectrometry. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-9, 2022. DOI: 10.15392/2319-0612.2022.1789

    Abstract: In this work, the insensitive layer thickness of a PIN photodiode (SFH206K - Osram) has been measured by varying the incident angle of a collimated monoenergetic alpha particle beam. This technique is based on variations in the path lengths of alpha particles through the insensitive layer and the correspondent energy losses when they impinge on a diode surface at different angles. Therefore, the pulse heights of these alpha particles, closely related to the energies deposited in the active volume of the diode, also depend on their incident angle. So, the difference between the pulse height of alpha particles perpendicularly incident on the diode surface and at any incident angle enables the insensitive layer thickness to be assessed. The result obtained (711  23) nm, less than 1% of the intrinsic layer thickness, besides validating the employed method, demonstrates that the investigated diode is suitable for high resolution charged particle spectrometry.

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  • IPEN-DOC 29133

    BORRELY, S.I. ; REDÍGOLO, M.M. ; VILLARD, B.D. ; LEBRE, D.T. ; TOMINAGA, F.K. . Degradation and toxicity of amoxicillin after electron beam irradiation. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-8, 2022. DOI: 10.15392/2319-0612.2022.1894

    Abstract: A recent and growing concern in environmental studies is the presence of antibiotics in wastewater, which contributes to antimicrobial resistance building. Amoxicillin, according to the World Health Organization, is one of the most consumed antibiotics worldwide, for being a first line therapy for common infections. Among several drug degradation methodologies, electron beam irradiation (EBI) is presented as an efficient and green treatment. This work presents data on amoxicillin degradation via EBI. Degradation rate was evaluated by LC/MS-MS, carbon removal efficiency was evaluated by TOC and ecotoxicity assays were performed employing Vibrio fischeri. Chromatographic results indicate an efficiency removal of 97.65% at 0.75 kGy and concentration below the limit of detection with increasing absorbed dose. Low mineralization (up to 10%) was achieved at 3.0 kGy. Regarding toxicity, approximately 81% of toxicity removal was obtained at 0.75 kGy and a decrease in efficiency was achieved with higher doses. In conclusion, results indicate the low doses (0.75 kGy) as most effective for drug removal employing EBI.

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  • IPEN-DOC 29132

    NAGAI, M.L.E. ; SANTOS, P.S. ; PARRON, I.; LEE, F.M.; VASQUEZ, P.A.S. . Gamma radiation processing for disinfection of a 19th century photo album. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-6, 2022. DOI: 10.15392/2319-0612.2022.2008

    Abstract: A 19th century photo album was donated to the Hercule Florence Institute collection. After going through the quarantine, it was discovered that the album was contaminated by anobides. The album was sent for disinfestation treatment by ionizing radiation processing at IPEN. The dose applied was 3 kGy for the immediate eradication of the insects. Colorimetry analysis performed before and after irradiation found that treatment with ionizing radiation did not affect human color perception in the album and the photographs present.

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  • IPEN-DOC 29131

    ALMEIDA JUNIOR, J.N. ; POTIENS, M.P.A. ; RODRIGUES JUNIOR, O. . Development of an additional filtration system by 3D printing for the implementation of new X-ray beam qualities used in diagnostic radiology. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-7, 2022. DOI: 10.15392/2319-0612.2022.1992

    Abstract: The Calibration Laboratory (LCI) of the Nuclear and Energy Research Institute (IPEN-CNEN) offers calibration services for radiation measurements instruments used in radiation protection, diagnostic radiology and radiotherapy. LCI produces radiation qualities and irradiation conditions which are in accordance with the national and international standard requirements. In order to establish the recommended radiation qualities for diagnostic radiology, X-ray beams generated in laboratory are modified for the irradiation conditions found in equipment routinely used in healthcare services. In this work, a new additional filtration system was developed to be adapted to the existing filter system at LCI. The new filter support can be coupled to the PTW Bench Control installed at the LCI X-ray system. Using a FDM 3D printer, a support model and a set of drawers were developed for the placement of additional filters. The models were also developed to fit each specific drawer of each filter to be used in the laboratory routine, coupled to the specific sensors that fit the spaces of the support part. Additionally, a microcontroller based on Arduino, micro switches, low- and high-level programming, allow checking of drawer status and integration of information with the laboratory control system. The system allows the recognition of the filter inserted in the drawer from sensors attached to the support. Tests were carried out to verify the usability of the system in the routine, adding Ag (silver) and Cu (copper) filters, for the characterization of attenuated radiation beams of interest in diagnostic radiology.

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  • IPEN-DOC 29130

    SILVA, C.A.J. ; BRAGUIN, L.N.M. ; ROSSI, J.L. ; SCAPIN, M.A. ; COSTA, I. ; SAIKI, M. . Analyses of magnesium-based alloys by nuclear techniques. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-12, 2022. DOI: 10.15392/2319-0612.2022.1969

    Abstract: Magnesium-based alloys have been proposed for use in temporary biomaterials in the applications that request their biocompatibility and degradability. Analyses of these alloys are of great interest to verify if their element composition is within the product specification and also to evaluate the impurities that may cause toxic effects to the human health or influence in their corrosion processes. In this study, nuclear techniques of neutron activation analysis (NAA) and wavelength dispersive X ray fluorescence spectrometry (WD XRFS) were applied in the analyses of two magnesium-based alloys: commercially pure magnesium (CP-Mg) and AZ31 alloy. The NAA procedure consisted of irradiation aliquots of sample and synthetic element standards followed by measurements using a HGe detector and the WD XFRS was carried out using the Model RIX 3000 X-ray spectrometer. In the CP-Mg sample several element impurities were quantified. In the AZ31 alloy, the alloying element mass fractions were within the product specification and the impurities of As, La, Na and Sb were also quantified. Nickel and sulfur were quantified only by WD XFRS. The Horwitz method was a good parameter to evaluate the repeatability of the results in Al, Mg, Mn and Zn determinations. In conclusion, the results indicated the viability of using NAA and WD XFRS in the analyses of magnesium-based materials mainly due its multielement determinations, precision of the results, quantification of elements in a wide range of mass fractions and the lack of need for sample dissolution.

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  • IPEN-DOC 29129

    NERY, A.D. ; NISTI, M.B. ; SAUEIA, C.H.R. ; MAZZILLI, B.P. . Determination of natural radionuclides (Ra-226, Po-210, Ra-228 and K-40) and Cs-137 in fish consumed in the city of São Paulo. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-17, 2022. DOI: 10.15392/2319-0612.2022.1941

    Abstract: The aim of the study was to determine the activity concentration of the natural radionuclides (226Ra, 210Po, 228Ra and 40K) and artificial radionuclide 137Cs in the muscle of the marine fish species most consumed in the city of São Paulo and to evaluate the annual effective dose due to the consumption of the fish. Samples were collected in the supermarket chain Extra and Carrefour and in the distribution center CEAGESP. Six fish species were selected among the most available and consumed in São Paulo city: anchovy, tuna, dogfish, croaker, hake and sardine. After the sample preparation procedures, the determination of 226Ra, 228Ra, 40K and 137Cs was carried out by gamma spectrometry and the determination of 210Po by alpha spectrometry. The results obtained for all the species studied are below the limits adopted by the Brazilian Standards for 137Cs and, therefore, their consumption offers no risk due to the ingestion of this radionuclide. The concentration obtained for the radionuclides 226Ra, 210Po, 228Ra and 137Cs in the fish samples analyzed are low and of the same order of magnitude as data from the literature. The results obtained for the doses, for all the species studied, showed that their consumption offers no risk of exposure due to the ingestion of the analyzed radionuclides.

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  • IPEN-DOC 29128

    SUZART, K.F. ; PEREIRA, M.C.C. ; HAMADA, M.M. ; MESQUITA, C.H. . Zonal refining and Bridgman technique for CsI:Tl scintillation crystal growth. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-14, 2022. DOI: 10.15392/2319-0612.2022.1925

    Abstract: This work describes the development of the crystal cesium iodide doped with thallium (CsI:Tl) for use as a radiation detector. For CsI salt purification the zonal refining methodology using a horizontal oven at a constant temperature of 700 °C was used. The high temperature region corresponds to approximately 10% of the salt bed containing (260 mm). This region moves at a speed of 50 mm/h. The crystal growth was carried out by Bridgman technique, using a vertical oven at speed of 1 mm/h.

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  • IPEN-DOC 29127

    FERREIRA, H.J. ; ZEITUNI, C.A. ; RIGO, M.E.Z. ; SANTOS, H.N. ; ROSERO, W.A.A. ; ALCANTARA, G.F. ; ROSTELATO, M.E.C.M. . Comparative analysis between radioactive seed localization and wire-guided for non-palpable breast cancer surgery. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-13, 2022. DOI: 10.15392/2319-0612.2022.1909

    Abstract: The conservative surgery for impalpable breast cancer requires an intraoperative localization method that guides the identification and correct excision of the lesion. The aim of this study is to comparatively analyze two intraoperative breast localization technologies, wire guided localization (WGL) and radioactive seed localization (RSL), regarding their surgical efficacy through the outcomes of surgical margins, intraoperative re-excision, reoperation and recurrence. To this end, a systematic search was realized in databases for clinical trials that match with the study eligibility criteria. The selected studies were evaluated for their methodological quality; the data were then collected and quantitatively synthesized. The results comprised thirty-eight studies that match the eligibility criteria. The main outcomes reported demonstrating that the RSL is at least equivalent to the WGL in efficiency rates. These results confirm the method applicability for impalpable breast lesions surgery in an effective way, in addition to presenting organizational optimization of radiology and surgery services by allowing the surgery to be performed up to two months after seed implantation.

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  • IPEN-DOC 29126

    NISTI, M.B. ; MADUAR, M.F. ; DAMATTO, S.R. ; ALENCAR, M.M. . Counting efficiency in gamma-ray spectrometry with different sample volumes for the same geometry. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-13, 2022. DOI: 10.15392/2319-0612.2022.1884

    Abstract: The aim of this study is to determine an easy and fast method to calculate efficiencies in different volumes, in the same counting geometry, for gamma-ray spectrometry technique. Reference Material Soil IAEA 326 was packed in a 100 mL capacity polyethylene bottle with different masses and volumes, and sealed for about four weeks, prior measurement, in order to ensure that radioactive equilibrium had been reached between 226Ra and its progeny. After this time, they were measured by gamma-ray spectrometry with a hyper-pure germanium detector. The masses of the reference material used were 25, 60, 80, 95 and 128g. The energies of gamma-rays used in this paper are recommended due to the considerations: gamma intensity value, peak quality, spectral region without interference and the gamma- ray energies of the 238U and 232Th series very important for determining the natural radioactivity. The efficiency values obtained compared to the adjusted efficiency values were similar and presented a good correlation coefficient. The performance was acceptable for all different masses studied, indicating results consistent for the method. The proposed method could be useful as a tool for laboratories, dealing with of samples on a routine basis, by reducing the cost on the purchase of another counting geometry and optimizing the use of the detection system, thus improving their performance.

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  • IPEN-DOC 29125

    ALMEIDA, M.A. ; AYLLON, R.M. ; ANGELINI, M. ; VICENTE, R. ; SILVA, P.S.C. . Evaluation of recovery yields of 60Co and 137Cs in extraction procedures. Brazilian Journal of Radiation Sciences, v. 10, n. 3B, p. 1-8, 2022. DOI: 10.15392/2319-0612.2022.2003

    Abstract: Nuclear technology has been implemented in several sectors of society, among them, it is possible to highlight medicine, industry, research, among others. The high demand of these nuclear applications has caused problems with regard to the generation of radioactive waste. The laser ablation method has been pointed out in the last years for the decontamination of surfaces and the contamination removed is completely retained in paper filters. This requires a safe and inexpensive method to perform the characterization of the radioisotopic inventory present in the laser filter samples. In this study, the extraction and quantification of the radionuclides present in the filter was evaluated using 60Co and 137Cs radionuclides. Two forms of extraction were tested: with Soxhlet equipment and by digesting the filter samples in a beaker, both using 3M HNO3 as extractant. The chemical yield was calculated using gamma ray countings obtained before and after extraction. It was observed that the extraction method by digesting the filter directly in a beaker presented the highest yield recovery results.

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  • IPEN-DOC 29124

    BARONI, D.B.; BORSOI, S.S.; MATTAR NETO, M. ; OLIVEIRA, P.S.P. ; MATURANA, M.C.. Licensing approach applicable to land facilities supporting nuclear-powered submarines. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-13, 2022. DOI: 10.15392/ 2319-0612.2022.2083

    Abstract: The nuclear licensing process is a fundamental stage for the design and deployment of a nuclear facility. In Brazil, the licensing process of Central Nuclear Almirante Álvaro Alberto (CNAAA) nuclear power plants, in Angra dos Reis - RJ, was established mainly based on the U.S. Nuclear Regulatory Commission (U.S.NRC) guidelines. However, for each purpose specific requirements are established which promote a standardization appropriate to the type of installation in question. Thus, not every nuclear installation can be adequately framed in the standards and requirements established for the licensing of a nuclear power plant, especially when considering nuclear facilities for strategic and defense purposes. For instance, the Specialized Maintenance Complex (CME) project is being developed by the Brazilian Navy and aims to offer all the structures and systems for support on land to the first Brazilian nuclear-powered submarine. Therefore, when considering the interfaces between maritime/naval systems and operations, the purpose and specificity of installations such as CME extrapolate the commonly established nuclear normative framework. Due to the innovation of this type of installation in Brazil, there is no specific regulation for its licensing, constituting a unique situation for both the Brazilian Navy (applicant) and the National Nuclear Energy Commission - CNEN (Brazilian Nuclear Licensing Agency, which, soon, will have its function incorporated into the National Nuclear Safety Authority, ANSN). Even when researching standards and other guides in ostensible sources of nations that hold nuclear reactor technology for naval propulsion (and land support facilities), no normative guidance dealing specifically with the safety analysis and licensing of this type of installation has been identified. Thus, this paper proposes a first approach and analysis of the standards used by the U.S. Department of Defense (U.S.DOE) comparing them to the standards of the U.S. Nuclear Regulatory Commission (U.S.NRC) aiming to compose a specific normative proposition to carry out the safety analysis and licensing of a nuclear-powered submarines land support facility.

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  • IPEN-DOC 29123

    LEE, S.M. ; YORIYAZ, H. ; CABRAL, E.L.L. . Radiation shielding for a nuclear fusion device with inertial electrostatic confinement. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-13, 2022. DOI: 10.15392/2319-0612.2022.1997

    Abstract: In an inertial electrostatic confinement nuclear fusion device, IECF, thermal neutron population is created near the neutron shielding that is proportional to the fast neutrons generation rate; nevertheless, this proportionality varies with the experimental arrangement. Thus, to properly measure the fast neutron generation rate by the IECF device it is necessary to previously elaborate a suitable neutron transport model between the IECF device and the radiation shield, where the neutron detector will be located. This model is elaborated using the Monte Carlo N-Particle Code and the same is used to design the required radiation shield for the safe operation of the device.

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  • IPEN-DOC 29122

    SANTOS, A.G.M. ; SUZART, K.F. ; RODRIGUES, P.S. ; DEL MASTRO, N.L. . Study on the sociocultural profile of women working in a Brazilian nuclear area. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-16, 2022. DOI: 10.15392/2319-0612.2022.1882

    Abstract: Female representation in nuclear technology is still a global issue in terms of gender equality and there are still a low number of women in this area. The objective of this work was to evaluate the female participation in a nuclear research institute (an institution linked to the Sao Paulo state and the Brazilian federal government), to verify how the women who work in this unit are distributed, what is their area and position at career levels. The survey was carried out through an online form, answered voluntarily, which had questions to outline the profile of these women, as well as to understand how the female presence was shown in the workplace. The results showed that the majority profile is white women, graduate students aged up to 41 years, natives of the Southeast, predominantly from São Paulo, who are/were mentored by men, who do not know the Women in Nuclear association and a considerable percentage are unaware of the pioneer researcher in their core area, showing the lack of information about female representation in this field. It is noticed that in Brazil, the construction of an equal representation in the nuclear area is in progress and still has a long way to go, showing that research such as the present survey and dissemination of events about women is something that needs to be done more frequently to emphasize the importance of female presence in the sciences.

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  • IPEN-DOC 29121

    FERRARI, L.A. ; LIMA, L.M.P.R. ; RODRIGUES, E.A. ; PEREIRA, M.A.M.G. ; LIMA, M. ; PERINI, E.A. ; AYOUB, J.M.S. ; SENEDA, J.A. . Energy and Covid 19: analysis of the impact on the global energy matrix. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-26, 2022. DOI: 10.15392/2319-0612.2022.1966

    Abstract: Pandemics reverberated their times, changing social and economic contexts, prompting, and redirecting changes in social ties, business, and education, restructuring the world that generated them. In this context, this study aims to assess the impact of the COVID-19 pandemic on the global energy matrix, supported by an analysis of consumption, demand, and GDP from January 2019 to June 2021. The energy balance showed variations in this period, with impacts on the environment. We will assess whether the changes will be lasting.

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  • IPEN-DOC 29120

    CARVALHO, D.S.M. ; MATTAR NETO, M. . Encapsulated OSB energy absorption potential: a preliminary analysis. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-15, 2022. DOI: 10.15392/2319-0612.2022.1874

    Abstract: The transport of radioactive substances is, in many ways, necessary in the context of the nuclear fuel cycle that aims to generate energy or radioisotopes. In the event of a possible accident, the shock-absorbing parts reduce the mechanical stresses on the other components of the transport packaging, since a large part of the kinetic energy is absorbed by the shock absorber. To standardize the design of the research reactor spent fuel assembly transport devices by numerical analysis, a set of dynamic simulations of a benchmark was conducted to representatively capture the phenomena found in the drop tests used in project qualifications. This study aims to present a comparison of different ways of applying wood and wood composites as a useful and accessible impact-absorbing material. The necessary numerical modelling characteristics are validated and the phenomena present in non-isotropic materials are discussed. This study demonstrates the application of material models where energy absorption is the main structural function. In this case, the orientation of the wood fibers became sensitive with an approximate difference of 10% more in the impact absorption potential, without considerable variation in the duration interval of the maximum deceleration.

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  • IPEN-DOC 29119

    SOAVE, A. ; MATTAR NETO, M. . Design considerations for rectangular bolted full face flanged joints for surface condensers. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-17, 2022. DOI: 10.15392/2319-0612.2022.1989

    Abstract: Rectangular bolted full face flanged joints are widely used in surface condensers within the power generation industry including the nuclear one. In order to design these components, it is necessary to analyze the flanged joint from the point of view of structural strength and leak tightness. This work presents an analytical procedure applied to a rectangular bolted flange to determine the thickness of the flange, the bolt stresses and leak tightness conditions. First, the proposed analytical procedure is validated by comparing its results with those from finite element analysis (FEA) using non-linear approach considering the behavior of the materials, gasket and contacts. In addition, the proposed procedure is applied to the design of a rectangular flanged joint of a steam surface condenser using two different gaskets: compressed non-asbestos fiber gasket and NBR elastomer gasket. The obtained results show a better performance of the NBR elastomer gasket in comparison with compressed fiber gasket: better sealing condition, reduction of the flange thickness and reduction of the bolt stresses. It is important to highlight there are practically no references of procedures for design of non-circular full face flanged joints.

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  • IPEN-DOC 29118

    GALVAO, H.P. ; SHORTO, J.M.B. ; SOBRINHO, G.T.; ABE, A.Y. ; GIOVEDI, C.. Passive Autocatalytic Recombiner perfomance assessment using COCOSYS. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-14, 2022. DOI: 10.15392/2319-0612.2022.1906

    Abstract: The progression of severe accidents in nuclear reactors is characterized by a diversity of phenomena that are Beyond Design Basis (BDBA), such as Direct Containment Heating (DCH), Molten Corium Concrete Interaction (MCCI), hydrogen detonation, and others. Currently, there are several devices and systems that allow mitigating the progression of these events, avoiding the failure of the physical barriers between the nuclear power plant and the environment. In this context, the present work aims to reproduce the HR-14 experiment carried out at the Thermal-hydraulic, Hydrogen, Aerosols and Iodine (THAI) test facility through the Passive Autocatalytic Recombiners (PAR) performance assessment with the COCOSYS code. The analysis of the convergence of the results was performed using the Fast Fourier Transform Based Method (FFTBM) and showed that the results had sufficient accuracy with the experimental data.

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  • IPEN-DOC 29117

    PALADINO, P.A. ; BIATY, F.P. ; JULIAO, A.P.; SABUNDJIAN, G. . PLATAGAM: a video game structured as a didactical material for divulgation of some of the benefits of the Gamma Radiation produced in the Cobalt-60 Multipurpose Irradiator at IPEN’s facilities. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-17, 2022. DOI: 10.15392/2319-0612.2022.1851

    Abstract: This paper aimed at the conception and implementation of a platform video game designed to make known some of the benefits of the use of Gamma Radiation produced in the Cobalt-60 Multipurpose Irradiator, built with Brazilian technology at IPEN’s facilities. Unity 3D game engine and some other software for image editing were used. Four missions await the player, illustrating the following benefits of gamma radiation irradiation: on foods and beverages to retard deterioration and interrupt microorganisms proliferation; on tilapias, which skins are used in bandages for burns; on surgical materials as a sterilization procedure; and, finally, on museum items, for eradication of plagues on the collection. The authors hope that the offering of this didactic material will aid some effective Science Learning, mainly about pacific uses of Nuclear Technology.

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  • IPEN-DOC 29116

    BARONI, D.B.; BORSOI, S.S.; MATTAR NETO, M. ; OLIVEIRA, P.S.P. ; MATURANA, M.C.. Evaluation of “Safety Related” and “Important to Safety” terminology for safety classification of nuclear installation items in Brazil. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-17, 2022. DOI: 10.15392/2319-0612.2022.1960

    Abstract: In general terms, safety demonstration of nuclear installations is carried out through an assessment of compliance with design criteria and safety requirements established in national and international codes and standards applicable to each type of installation. In addition, a safety analysis consisting of installation behavior study during its useful lifetime, shall be developed considering normal operating conditions, transients, and postulated accidents, to determine safety margins and verify the adequacy of items designed to prevent accidents or mitigate their consequences. Also, design requirements applicable to each installation item depend on its classification with respect to safety. Thus, safety classification of structures, systems, and components (SSCs) must be performed based on adequate methods and clear and consistent criteria to ensure that an overall safety level expected for the installation is achieved. It is worth emphasizing the importance of the terminology adopted and the understanding of concepts definitions used in a safety classification process. The objective of this paper is to present a review of the application of “safety related item” and “item important to safety” terminology, evaluating definitions and interpretations given by the International Atomic Energy Agency (IAEA), the United States Nuclear Regulatory Commission (U.S.NRC) and the National Nuclear Energy Commission (CNEN) of Brazil. In this work, this subject is raised to demonstrate that divergent definitions and misinterpretations of concepts may result in inconsistencies in SSCs safety classification.

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  • IPEN-DOC 29115

    AGUIAR, A.S. ; LEE, S.M. ; SABUNDJIAN, G. . Consequence analysis of a Station Blackout in Brazilian nuclear power plant Angra 2. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-14, 2022. DOI: 10.15392/2319-0612.2022.1918

    Abstract: The article consists, through a Severe Accident, evaluating the impact of radionuclides released into the atmosphere in the vicinity at Nuclear Power Plant. The source term used in present work is obtained by means of proportionality between Angra 1 and Angra 2. That is, the source term of Angra 2 is calculated based on its activity estimated from numbers of fuel pellets of both power plants and the already known activity of Angra 1. This calculation resulted in total activity of Angra 2 equivalent to 146.18% of activity of Angra 1. The results indicate that for severe accident scenarios, the protective measures to be adopted will be general emergency; and the impact area, which currently has a distance of 5 km, would become greater than this value.

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  • IPEN-DOC 29114

    ANDRADE, L.G.F. ; DONATO, G.H.B.; MATTAR NETO, M. . Effect of mounting orientation on testing equipment on elastic compliance of clamped SE(T) specimens: an exploration. Brazilian Journal of Radiation Sciences, v. 10, n. 3A, p. 1-21, 2022. DOI: 10.15392/2319-0612.2022.1863

    Abstract: The accurate evaluation of fracture mechanics properties is key to the safety of operation of high responsibility structures, such as nuclear reactor components. This paper evaluates the impact of mounting orientation on the test machine of clamped SE(T) (SE(T)c) specimens on their compliance. The elastic unloading compliance is a commonly used technique to measure the crack depth of specimens within fracture mechanics tests. Inaccurate measurements affect the reliability of resulting properties. Two mounting orientations are evaluated in this paper, together with two SE(T)c specimens with different width-to-thickness ratios (W/B=2 and W/B=4). The conclusions show that machine stiffness is different in the two orientations, and that this value has the potential to affect crack depth prediction. On the other hand, the analysis scope of this work was unable to detect significant differences between the two orientations, probably because loading was limited to maintain specimen integrity. Further investigation is necessary to precisely address the impact of this effect.

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  • IPEN-DOC 29113

    BARCELLOS, HENRIQUE ; MATSUDA, HYLTON ; LAPOLLI, ANDRE L. ; SUMIYA, LUIZ C. do A. ; JUNQUEIRA, FERNANDO de C. ; COSTA, OSVALDO L. da . Design and assembly of an XY-type beam current monitor for cyclotron accelerators. Applied Radiation and Isotopes, v. 192, p. 1-5, 2023. DOI: 10.1016/j.apradiso.2022.110550

    Abstract: A water-cooled XY-type beam current monitor was designed, manufactured and assembled in a cyclotron accelerator beam transport line. Tests were performed, demonstrating that apparatus is an instrument of great assistance in proton beam position. The XY-type beam current monitor has been widely used in liquid target irradiations, employing irradiation system which were originally designed for irradiations on 18 MeV cyclotron accelerator (Cyclone 18, IBA) only, however, with this apparatus, the target may be exchanged between the 30 MeV (Cyclone 30, IBA) and 18 MeV cyclotrons.

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  • IPEN-DOC 29112

    SILVA, WILMAR D. da; ANDRADE, SONIA A. de; MEGALE, ANGELA A.A.; SOUZA, DANIEL A. de; SANTANNA, OSVALDO A.; MAGNOLI, FABIO C.; GUIDOLIN, FELIPE R.; GODOI, KEMILY S.; SALADINI, LUCAS Y.; SPENCER, PATRICK J. ; PORTARO, FERNANDA C.V.. Antibodies as snakebite antivenoms: past and future. Toxins, v. 14, n. 9, p. 1-13, 2022. DOI: 10.3390/toxins14090606

    Abstract: Snakebite envenomation is considered a neglected tropical disease, affecting tens of thousands of people each year. The recommended treatment is the use of antivenom, which is composed of immunoglobulins or immunoglobulin fragments obtained from the plasma of animals hyperimmunized with one (monospecific) or several (polyspecific) venoms. In this review, the efforts made in the improvement of the already available antivenoms and the development of new antivenoms, focusing on snakes of medical importance from sub-Saharan Africa and Latin America, are described. Some antivenoms currently used are composed of whole IgGs, whereas others use F(ab’)2 fragments. The classic methods of attaining snake antivenoms are presented, in addition to new strategies to improve their effectiveness. Punctual changes in immunization protocols, in addition to the use of cross-reactivity between venoms from different snakes for the manufacture of more potent and widely used antivenoms, are presented. It is known that venoms are a complex mixture of components; however, advances in the field of antivenoms have shown that there are key toxins that, if effectively blocked, are capable of reversing the condition of in vivo envenomation. These studies provide an opportunity for the use of monoclonal antibodies in the development of new-generation antivenoms. Thus, monoclonal antibodies and their fragments are described as a possible alternative for the production of antivenoms, regardless of the venom. This review also highlights the challenges associated with their development.

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  • IPEN-DOC 29111

    BRICENO, MARISOL P.; CARIACO, YUSMARIS; ALMEIDA, MARCOS P.O.; MIRANDA, NATALIA C.; ARAUJO, ESTER C.B.; SANTOS, SOFIA N. dos ; BERNARDES, EMERSON S. ; SILVA, NEIDE M.. Effects of Notch signaling pathway inhibition by dibenzazepine in acute experimental toxoplasmosis. Tissue and Cell, v. 79, p. 1-11, 2022. DOI: 10.1016/j.tice.2022.101952

    Abstract: Notch signaling pathway plays a crucial role in cellular fate across species, being important for the differentiation and development of several cell types. The aim of this study was to evaluate the effect of Notch inhibition pathway by dibenzazepine (DBZ) in histological and inflammatory alterations and, tissue parasitism in acute Toxoplasma gondii infection. For this, C57BL/6 mice were treated with DBZ before infection with T. gondii, and the small intestine, lungs and liver were analyzed. The genes related to Notch signaling pathway were assayed through qPCR in the organs, and cytokine measurement was performed in serum samples. In the small intestine, T. gondii infection impaired the Hes1 and Math1 mRNA expressions, increased the inflammation and decreased goblet and Paneth cell numbers. The DBZ-treatment was able to partially preserve these cells, however, the parasitism and inflammation were not altered. In parallel, the high IL-2, IL-6, TNF and, IFN-γ levels induced by infection were not changed with the DBZ treatment, with the IFN-γ levels even higher. In contrast, in the liver and lungs, the DBZ-treatment diminished parasitism and inflammation. Our results highlight that Notch pathway inhibition in T.gondii infection results in different parasitological and inflammatory outcomes depending on the organ analyzed.

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  • IPEN-DOC 29110

    RODRIGUES, ELAINE A. ; FERREIRA, MAURICIO L.; CARVALHO, AMANDA R. de ; BUSTILLOS, JOSE O.W.V. ; VICTOR, RODRIGO A.B.M.; SODRE, MARCELO G.; ANDRADE, DELVONEI A. de . Land, water, and climate issues in large and megacities under the lens of nuclear science: an approach for achieving Sustainable Development Goal (SDG11). Sustainability, v. 14, n. 20, p. 1-19, 2022. DOI: 10.3390/su142013646

    Abstract: Nuclear science and technology (NST) offers a multitude of applications and tools and has a high level of regulation. However, its contribution to the achievement of global development goals is still incipient. Although its application is directly related to many fields, especially sustainability, the current literature does not relate it to socio-environmental issues, hindering the adoption of public policies based on isotopic and nuclear solutions. In large and megacities, the promotion of human well-being and the conservation of ecosystems are urgent global challenges, especially as a function of the growing expansion of land use modification, water scarcity, and climate change. The relationship between society and NST is addressed in this study, which aims to show how and in what ways the emerging and innovative nuclear and isotopic solutions contribute to the urban dimension of the United Nations 2030 Agenda, expressed by SDG 11 (Sustainable Cities and Communities), and its connection to land, water, and climate change in cities. This gap in knowledge compromises the targeting of resources to improve NST as a development strategy. Demystifying NST and increasing collaboration between ecosystem services and other issues related to sustainability in cities are key to implementing global development policies, especially at the local governance level.

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  • IPEN-DOC 29109

    SANTOS, RAPHAEL A.V. dos; SARKIS, JORGE E. de S. ; ANDRADE, DELVONEI A. de . Gestão da informação em situação de crise: reflexões sobre comunicação nos acidentes de Mariana e Brumadinho / Information management in crisis situation: reflections on communication in the accidents of Mariana and Brumadinho. SODEBRAS, v. 17, n. 201, p. 8-21, 2022. DOI: 10.29367/issn.1809-3957.17.2022.201.08

    Abstract: O objetivo desse artigo é refletir sobre o processo de gestão da informação em situações de crise no contexto da Sociedade em Rede. Tal análise será feita a partir da observação dos procedimentos de gestão da comunicação realizados nos acidentes das barragens de Mariana e Brumadinho, em Minas Gerais, divulgados através da mídia e em documentos oficiais. Com base nos dados e sob a lógica do conceito de poder proveniente da comunicação, o artigo indica que a cultura de treinamentos em gestão da informação, o investimento em análise e o desenvolvimento de protocolos de comunicação para situações de crise são conceitos chaves para que as organizações possam proteger seus interesses sem afetar a relação de confiança com a sociedade.

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  • IPEN-DOC 29108

    SANTOS, NATHALIA V. dos; VIEIRA, CAROLINA L.Z.; SALDIVA, PAULO H.N.; DE ANDRE, CARMEN D.S.; MAZZILLI, BARBARA P. ; ANDRADE, MARIA de F.; SAUEIA, CATIA H. ; SAIKI, MITIKO ; VERAS, MARIANA M.; KOUTRAKIS, PETROS. Accumulation of trace element content in the lungs of São Paulo city residents and its correlation to lifetime exposure to air pollution. Scientific Reports, v. 12, p. 1-7, 2022. DOI: 10.1038/s41598-022-15048-2

    Abstract: Heavy metals are natural and essential elements of the environment and living beings, produced from natural (e.g. volcanic activity and cosmic ray-induced spallation) and anthropogenic processes (e.g. industrial and fossil fuel combustion). High-concentrations of heavy metals and radionuclides are also originated from anthropogenic activities in urban and industrial areas. In this preliminary study, we analyzed the levels of heavy metals and Polonium-210 (210Po) in lung tissues in autopsies from residents of the city of Sao Paulo, SP, Brazil. In order to identify the link among sources of the heavy metals in lungs, factor analysis was performed. Of the first four factors, which explain 66% of the total variability, three were associated with vehicular sources. The fitting of a regression model with 210Po as the response variable and with the four factors as explanatory variables, controlling for age, sex and tobacco, showed a significant association between the concentration of polonium and the first factor that is generated by catalysts and brakes (coefficient = 0.90, standard error = 0.33, p = 0.016). Our findings suggest an association between traffic-related trace metals and 210Po in lung autopsies.

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  • IPEN-DOC 29107

    CALEGARI, RUBENS P.; SILVA, ERIC A. da ; SILVA, ANA P.M. da; GOMES, MARCELO P.; MOTA, LAYNA A.; ARTHUR, VALTER; BAPTISTA, ANTONIO S.. Wort disinfection treatment with electron beam for bioethanol production. Scientia Agricola, v. 80, p. 1-11, 2023. DOI: 10.1590/1678-992X-2021-0260

    Abstract: Microbial contamination of the wort during the fermentation process causes significant losses in ethanol production worldwide and creates a dependence of the industry on chemicals and antibiotics to control contamination. Therefore, this study used electron beam (e-beam) to disinfect wort from sugarcane (Saccharum officinarum L.) molasses and investigate the bioethanol fermentation. Four treatments (T0 – T3) were carried out using ionizing doses of radiation through the electron accelerator: 0 (control), 10, 20, and 40 kGy. Total mesophiles, total bacteria, sucrose, glucose, fructose, phenolics, flavonoids, hydroxymethylfurfural (5-HMF), and Furfural were measured. An alcoholic fermentation assay was performed after the irradiation process. The irradiated treatments showed no inversion of sugars and formation of the inhibitory by-products flavonoids, furfural and 5-HMF, except for the phenolic compounds. The lower dose tested (10 kGy) reduced more than 99.9 % of the total mesophiles and more than 99.99 % of the total bacteria in the substrate. In the fermentation, the irradiated worts presented similar (p > 0.05) yields (92, 93, and 94 %) and ethanol productivity levels (0.89, 0.88, and 0.87 g L–1 h–1, for T1, T2, and T3 respectively). However, all treatments presented higher yields and productivity (p < 0.05) when compared to the control (88 % and 0.85 g L–1 h–1), highlighting the possible use of e-beam in wort fermentation at a lower dose (10 kGy). This allows reduction in losses caused by microbial contamination, besides increasing fermentation yield and productivity with lower energy consumption.

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  • IPEN-DOC 29106

    BEU, CASSIA M.L. ; LANDULFO, EDUARDO . Caracterização do perfil vertical do vento em Iperó (São Paulo) com o uso de um lidar doppler / Characterization of the wind vertical profile in Iperó (São Paulo) with the use of a doppler lidar. Revista Brasileira de Climatologia, v. 30, p. 424-444, 2022. DOI: 10.55761/abclima.v30i18.15582

    Abstract: Um lidar Doppler com alcance até 290 m operou continuamente por 1 ano no município de Iperó, interior de São Paulo. O lidar usado possui alta resolução vertical e temporal e estima além da velocidade e direção do vento horizontal, também a velocidade vertical do vento. O banco de dados gerado durante essa campanha experimental permitirá estudar fenômenos da Camada Limite Planetária, bem como validar modelos numéricos e auxiliar estudos de transporte e dispersão de poluentes. Neste trabalho é apresentada a caracterização do perfil vertical do vento e o ciclo anual entre Agosto/2017 e julho/2018.

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  • IPEN-DOC 29105

    SOUZA,CAIQUE M.P. de; MILITAO, VANDERLEI A.; SILVA, ISAIAS G.; OLIVEIRA, RENE R. de ; SERIACOPI, VANESSA; SILVA JUNIOR, WILSON C. da. Characterization of Ti-6Al-4V titanium alloy applied in hydroxyapatite coated hip prostheses / Caracterização da liga de titânio Ti-6Al-4V aplicada em próteses de quadril revestidas com hidroxiapatita. Research, Society and Development, v. 11, n. 8, p. 1-16, 2022. DOI: 10.33448/rsd-v11i8.30629

    Abstract: Titanium and its alloys are widely used as biomaterials in hard tissue replacements due to their unique physiological environment responses and chemical and mechanical properties, such as corrosion resistance, fatigue resistance, and ductility. Other metals used as biomaterials have elastic modulus with values ​​ten times higher than human bone, which can cause failure when there are impacts. Several studies report hip prosthesis failures due to fatigue. This article aims to carry out studies on the mechanical properties and fatigue resistance in an environment that simulates those of the joints of the human body, using hip prostheses manufactured with Ti 6Al 4V alloy with hydroxyapatite coating. Samples were taken from the neck region for microstructural characterization to identify grain size, inclusions, microhardness, tensile test, scanning electron microscopy, energy dispersion spectroscopy, X-ray fluorescence,e, and X-ray diffraction also performed. After applying more than 10,000,000 cycles with compressive forces ranging from -0.3 kN to -3.0 kN, no cracks were found and it was observed that the part suffered only elastic deformations.

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  • IPEN-DOC 29104

    COELHO, JESSICA F. ; FILHO, NIVALDO G.P. ; GUTIERREZ, ISABELY M.; GODOI, CAMILA M. ; GOMES, PAULO V.R. ; ZAMBIAZI, PRISCILLA J. ; SOUZA, RODRIGO F.B. de ; NETO, ALMIR O. . Methane‑to‑methanol conversion and power co‑generation on palladium: nickel supported on antimony tin oxide catalysts in a polymeric electrolyte reactor‑fuel cell (PER‑FC). Research on Chemical Intermediates, v. 48, n. 12, p. 5155-5168, 2022. DOI: 10.1007/s11164-022-04857-9

    Abstract: The use of palladium nickel catalysts with different compositions supported metal oxides, such as Sb2O5·SnO2 (ATO) catalyst combinations were employed to convert the methane-to-methanol in mild conditions using a fuel cell polymer electrolyte reactor. The catalysts used for the conversion of methane to methanol were characterized by XRD and observed the phases of ATO, the face-centered cubic structure of the Pd and Ni phases. All nanoparticles have a mean size between 9 and 12 nm as measured by TEM images. The products obtained from the methane oxidation, such as methanol and formate, were monitored using FT-IR spectroscopy to qualify the products formation, while High-Performance Liquid Chromatography was used to quantify them. In these studies, it was observed that as the electrical potential of the reactor increases, the generation of products decreases. The best results for the conversion of methane into methanol and energy co-generation were obtained from Pd50Ni50/ATO.

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  • IPEN-DOC 29103

    PEREIRA, VIVIANE S. ; NANDENHA, JULIO ; RAMOS, ANDREZZA ; OLIVEIRA NETO, ALMIR . Effects of TiO2 in Pd-TiO2/C for glycerol oxidation in a direct alkaline fuel cell. Journal of Fuel Chemistry and Technology, v. 50, n. 4, p. 474-483, 2022. DOI: 10.1016/S1872-5813(21)60171-8

    Abstract: The Pd-TiO2 electrocatalysts were synthesized via sodium borohydride reduction and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), cyclic voltammetry, chronoamperometry and attenuated total reflectance-Fourier transform infrared (ATR-FTIR). The X-ray diffraction experiments of the Pd-TiO2 showed peaks associated with Pd face-centered cubic (fcc) structure and peaks characteristics of TiO2 (anatase phase) with a tetragonal structure. The TEM images showed that the Pd and TiO2 nanoparticles were well distributed in the carbon support showing some clustered regions with nanoparticle sizes between 7 and 8 nm. Cyclic voltammograms showed an increase in current density values after the glycerol adsorption process. Experiments in alkaline direct glycerol fuel cells at 60 °C showed a higher power density for Pd-TiO2/C (70:30) in comparison to the commercial Pd/C electrocatalyst indicating that the use of the TiO2 co-catalyst with Pd nanoparticles had a beneficial behavior. This effect can be attributed to the electronic effect or to the bifunctional mechanism. Molecules with high-value added glyceraldehyde, hydroxypyruvate and formate were identified as electrochemical reaction products of glycerol on all prepared electrocatalysts.

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  • IPEN-DOC 29102

    SANTOS, CAROLINE C.; VALENCA, JOAO V.B.; D'ERRICO, FRANCESCO; MACHADO, ROGERIO; CALDAS, LINDA V.E. ; SOUZA, SUSANA O.. Effect of different solvents on the optically stimulated luminescence signal from MgB4O7:Ce,Li-loaded polymer films. Radiation Protection Dosimetry, v. 198, n. 16, p. 1230-1237, 2022. DOI: 10.1093/rpd/ncac161

    Abstract: The detailed dose analysis at the extremities remains a challenge, without affecting operators’ mobility and their tactile sense. Using films loaded with optically stimulated luminescence (OSL) crystals have been studied in order to overcome some of these challenges in 2D dosimetry. In this work, we investigated flexible polymeric films loaded with MgB4O7:Ce,Li to acquire a better understanding of the dependence of the dosimetric signal characteristics on the production process and the influence of using different powder grain sizes. In film production, five different solvents were used: acetone–benzene, dichloromethane, chloroform, tetrahydrofuran and formic acid. Our results indicate that acetone–benzene is the solvent mixture that less influences the signal emitted by treated crystals, in comparison with the signal emitted by the pristine crystal powder. Conversely, by using formic acid, the crystalline structure of the sample was most severely modified, leading to a drastic reduction of the emitted OSL signal. We found that the extent of the grain surface in contact with the solvent in the process is important and should be taken into consideration when choosing the proper grain size to be used.

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  • IPEN-DOC 29101

    SANTANA, JULYANA G. ; AKBULUT, MESHUDE; TEMPERINI, MARCIA L.A.; RANGARI, VIJAY K.; GUVEN, OLGUN; MOURA, ESPERIDIANA . Synergistic effect of e-beam irradiation and graphene oxide incorporation on thermal, mechanical, and barrier properties of poly (ethylene-co-vinyl alcohol) film. Radiation Physics and Chemistry, v. 199, p. 1-10, 2022. DOI: 10.1016/j.radphyschem.2022.110343

    Abstract: Graphene and its derivatives, such as graphene oxide (GO), have attracted enormous interest from academia and industry because of its unique electrical, mechanical, and thermal properties, which can lead to enhanced material performance. In the present study, low contents of GO were incorporated into the poly (vinyl alcohol-co-ethylene) (EVOH). First, the GO was prepared by chemical oxidation of graphite employing a modified Hummer's method. The GO content of 0.1–0.3 wt % was incorporated in the EVOH matrix using a twin-screw extruder and extrusion blown film process to prepare flexible films. EVOH/GO film samples were irradiated at 100 kGy, using a 1.5 MeV electron-beam accelerator, at room temperature, in the presence of air. GO was characterized by XRD, ATR-FTIR, FE-SEM, and TEM analysis. XRD patterns of GO show a sharp reflection peak at 2θ = 10° (d001) corresponding to a d-spacing at 8.84 Å, characteristic of GO. The non-irradiated and irradiated samples were characterized by XRD, FEG-SEM, TG, DSC, oxygen transmission rate (OTR), UV/VIS analysis, and tensile tests. EVOH/GO nanocomposite films had an improved oxygen barrier, while also retaining fairly good transparency. As an effect of e-beam irradiation, the thermal, mechanical, and barrier behaviors of the nanocomposite films were even better than non-irradiated film samples, and obviously better than neat EVOH. Thus, the incorporation of low contents of GO followed by e-beam radiation treatment might be an interesting alternative to produce packaging materials based on EVOH with outstanding performance even under very humid conditions.

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  • IPEN-DOC 29100

    OLIVEIRA, MARIA J.A. ; OTUBO, LARISSA ; PIRES, ADRIANA; BRAMBILLA , RODRIGO F. ; CARVALHO, ANA C.; SANTOS, PAULO S. ; OLIVEIRA NETO, ALMIR ; VASQUEZ, PABLO . Silver nanoparticles-based hydrogels synthetized by ionizing radiation for cleaning of tangible cultural heritage surfaces. Radiation Physics and Chemistry, v. 199, p. 1-8, 2022. DOI: 10.1016/j.radphyschem.2022.110345

    Abstract: The surfaces of the works of art are one of their most important parts since they interact directly with the observer's perception. On the other hand, they are also in direct contact with physical, chemical and biological agents that can induce degradation and signs of aging. Dust deposits, stains and aged layers of protection can degrade, causing irreversible damage to works of art. In this way, the removal of undesirable materials from artistic surfaces is essential to preserve cultural heritage articles. The aim of this work was to develop silver nanoparticles-based hydrogels and to study the behavior regarding solvent concentration, stability and ability to clean dirt samples based on paper and canvas. The hydrogels were synthesized (reticulated) by gamma rays having the simultaneous formation of silver nanoparticles (AgNP) in the same process. The samples were characterized by swelling tests, attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy, differential scanning calorimetry (DSC), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and optical microscopy (OM). The results showed the removal of dirt from the paper samples, as well as the softening of the dirt from the canvas, without leaving residues and without affecting the integrity of the art works submitted to treatment.

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  • IPEN-DOC 29099

    LIMA, LENI M.P.R. ; KODAMA, YASKO ; BAITELLO, JOAO B.; OTUBO, LARISSA ; SANTOS, PAULO de S. ; VASQUEZ, PABLO A.S. . Effects of ionizing radiation decontamination on botanical collections in herbaria. Radiation Physics and Chemistry, v. 202, p. 1-8, 2023. DOI: 10.1016/j.radphyschem.2022.110561

    Abstract: Herbaria collections are very sensitive to attacks from microorganisms and insects. Therefore, preservation strategies and appropriate treatments are essential to manage these artifacts. Decontamination by ionizing radiation has become an effective strategy to preserve cultural heritage objects and archived materials, achieving excellent results. Therefore, this work aimed to study the effects of Co-60 gamma radiation on botanical collections. To accomplish this, samples of exsiccates, including botanical pressed and dehydrated specimens from Asteraceae and Solanaceae families, collected on diferentes dates were selected from the Dom Bento José Pickel Herbarium (SPSF), located in São Paulo (Brazil). Irradiation was performed at the Multipurpose Gamma Irradiation Facility at IPEN, applying absorbed doses of 1 kGy, 6 kGy and 10 kGy. Gamma radiation effect was analyzed using colorimetry with CIELAB color space scale, scanning electron microscopy (SEM) and attenuated total reflectance with Fourier transform infrared (ATR-FTIR) spectroscopy. Results showed no significant colorimetric changes, or changes in the morphological properties of samples, indicating that this decontamination method can be used as an alternative treatment to eliminate insects and micro-fungi of botanical collections without the use of toxic substances.

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  • IPEN-DOC 29098

    GONCALVES, JOSEMARY A.C. ; MANGIAROTTI, ALESSIO; BUENO, CARMEN C. . Dose rate mapping of an industrial 60Co irradiator using an online photodiode-based dosimetry system. Radiation Physics and Chemistry, v. 200, p. 1-6, 2022. DOI: 10.1016/j.radphyschem.2022.110387

    Abstract: In this work, a housemade dosimetry system based on a thin photodiode is applied for online mapping of dose rates, between 2.6 and 37.7 Gy/h, delivered by a Panoramic 60Co industrial facility. The operational principle of the dosimeter relies on the real-time acquisition of the induced currents from the irradiated diode operating in the short-circuit mode without externally applied voltage. The radial mapping of the radiation field is performed by rotating the diode around the central axis of the panoramic irradiator, covering 360° at intervals of 18°. The results are benchmarked with alanine dosimeters, Monte Carlo simulations, and reference dose rates retrieved from the facility calibration. The overall consistency of the whole data complies with the maximum response variation (8%, k = 2) recommended by the International Standard Protocols for routine dosimeters in radiation processing dosimetry. It reveals that the photodiode-dosimetry system is a reliable alternative to map dose rate fields and the effectiveness of Monte Carlo simulations as a predictive tool for dose rate measurements in an irradiator.

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