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https://repositorio.ipen.br/handle/123456789/8934

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Smart electrolytes
2024 - SANTIAGO, ELISABETE I.; LINARES, JOSE J.
In this chapter, we will focus on polymeric electrolyte materials, widely used in low temperature electrochemical cells, both fuel cells and electrolyzers, in acid or alkaline environment. Within each section, each material will be described, with special emphasis on the durability studies and degradation issues observed. Special attention will be given to the proposal for overcoming the observed limitations.
Heat treatment influence on micromilling of additively manufactured titanium
2024 - GONCALVES, MARIA C.C.; MERGULHAO, MARCELLO V.; BATALHA, GILMAR F.; STOETERAU, RODRIGO L.
Recently, miniaturized products are being used as working tools by many fields, highlighting the medical and dental industries. With the development of Additive Manufacturing (AM) processes, these features can be produced with less material waste and with wide design possibilities by applying a ‘near-net-shape’ technique. Although, the AM parts require post-processing techniques to reach the required material properties, dimensions, and surface roughness and to reduce undesirable residual stresses. In this aspect, the micromilling process is usually applied to attain the desired dimensions and surface roughness and heat treatments to attain the desired material properties and to reduce residual stress. Nonetheless, the micromilling process can be done before or after the heat treatment. In this perspective, this research analyses the surface roughness results for the micromilled AM parts before and after the heat treatment, which is in important for planning the manufacturing route for these parts. Thus, this work aims to compare the surface roughness results of Sa, Sq, Ssk, Sku when performing the micromilling process on AM parts by Laser Powder Bed Fusion (LPBF), with and without heat treatment. For the experiments, the tool size, feed and cutting speed were varied in a full factorial design of experiments. After that, the surface roughness parameters were analyzed and compared for both workpieces. With the achieved results, it can be concluded that the surface texture (Ssk) for the heat-treated and non-heat-treated samples present a predominance of peaks. Also, there is a presence of inordinately high peaks and/or deep valleys on the surface (Sku), which can present an interference of the chips left on the surface not removed by the ultrasonic cleaning. By the analyses of the arithmetic mean deviation (Sa) and the root mean square height (Sq), a better surface quality was achieved when micromilling the samples before the heat treatment for greater tool size, for the specific set of parameters used. With the smaller tool size, a greater surface roughness was achieved if compared to the bigger tool size, though the difference between the samples were not expressive. Moreover, the results achieved in this work can be applied to improve the surface quality of the AM parts used in industry.
Polysaccharide-based nanotechnology approaches to deliver bioactive compounds for food applications
2023 - ROSALES, THIECLA K.O.; FABI, JOAO P.
Nanoencapsulation based on natural polysaccharides effectively protects and improves the bioavailability of different bioactive compounds. Food polysaccharides have essential functional properties to compose targeted delivery nanosystems in the intestine. This chapter describes the characteristics of the leading natural polysaccharides used as nanocarriers for application in food products. Also, it demonstrates the principal methodologies used for elaboration and applicability, indicating the characterization methods mechanisms for the formation and targeted release. The essential biomaterials for this purpose are chitosan, cellulose, and pectin, which can be used alone or combined with proteins to form nano-gels with multiple functionalities. Several methodologies can be used for preparation, such as molecular self-organization and ionic gelation. Nanoencapsulated bioactives based on these polysaccharides can be protected, maintain functional properties, thus increasing the absorption and bioavailability. Biocompatibility, biodegradability, and nontoxicity are the highlighted advantages of these biopolymers. In addition, they can be extracted from sustainable sources, such as industrial by-products. Several studies have proven the advantages and relevancy of biomaterials for protection against the environment, factors intrinsic to human digestion, and enhancing the beneficial effects of biologically active compounds. Nanoencapsulation based on polysaccharides effectively enables the inclusion of these compounds in foods or to develop new dietary supplements.
Perspectivas dos resíduos sólidos de saúde (RSS)
2023 - GONCALVES, MAX F.S.; LOPES, MARIA E.C.; MOL, MARCOS P.G.
Repositórios digitais institucionais
2023 - IGAMI, MERY P.Z.
Descreve-se a experiência do IPEN, objetivando compartilhar conhecimento e contribuir para o avanço do papel que os Repositórios digitais institucionais podem alcançar. O Instituto de Pesquisas Energéticas e Nucleares - IPEN - é um instituto público federal localizado em São Paulo, cuja missão é produzir conhecimento e tecnologia relacionados com as aplicações das técnicas nucleares e das ciências relacionadas, dedicando-se também à formação de recursos humanos, mediante um programa de Pós-Graduação. O relato diz respeito ao processo de migração da base de dados referencial de produção científica institucional, construída na década de oitenta, para o atual Repositório Digital (RD). A citada base de dados referencial foi organizada segundo padrões internacionais, reunindo e atribuindo um tratamento diferenciado à produção científica da instituição, desde a sua criação. Descreve-se essa organização e os atributos que facilitaram o processo de migração e que se tornaram fatores decisivos para o sucesso da atividade. Para funcionamento do atual RD, foram desenvolvidas funções e acrescentados metadados, além dos tradicionais, os quais se constituem em filtros, a fim de favorecer o controle, o monitoramento, a extração de relatórios e principalmente a interoperabilidade com o Sistema Gerencial Institucional, o SIGEPI. O RD fornece dados em tempo real e em fluxo contínuo, apresenta estatísticas de produtividade para a elaboração de indicadores científicos e informações gerenciais para subsidiar os gestores do IPEN. O RD foi construído dentro dos pressupostos do movimento de Acesso Aberto e, por meio de ações de valor agregado atribuído, tornou-se um instrumento de gestão do capital intelectual institucional. Descreve-se também o planejamento para futuras atividades a serem desenvolvidas com o RD.
Nanodiagnostic tools for mycotoxins detection
2022 - THIPE, VELAPHI C.; MENDES, GIOVANNA de O.A.; ALVES, VICTORIA M.; SOUZA, THAYNA; AJAYI, RACHEL F.; LUGAO, ADEMAR B.; KATTI, KATTESH V.
In recent decades, mycotoxin contamination of agricultural food items has garnered considerable attention because to their high acute or chronic toxicity in humans and animals, resulting from consumption and exposure duration to contaminated food or feed. This is exacerbated by the impact of the Covid-19 pandemic, civil wars, and conflicts (e.g., the Russia-Ukraine conflict, Yemen, Ethiopia, Afghanistan, and others), which further strain the food security and nutritional status of the most vulnerable demographic groups, which are predicted to continue to deteriorate due to health and socioeconomic factors. The presence of these mycotoxins in food and animal feed has a negative impact on public health and the economy; consequently, it is crucial to detect and quantify these toxins in agricultural lots. Maintaining food quality and minimizing adverse effects on human and animal health are dependent on early detection. Conventional techniques for detecting mycotoxins include enzyme-linked immunoassay (ELISA), gas chromatography (GC), thin-layer chromatography (TLC), and high-performance liquid chromatography (HPLC). Nanomaterial-based sensor technologies provide diverse mitigation methods for quantifying single or multiple analytes, as mycotoxin co-occurrence in a single matrix has become more common. In this chapter, we describe recent advancements in nanodiagnostic techniques that permit multiplex detection of mycotoxins on a single platform. In addition, we discuss certain commercially available lateral flow immunoassay (LFIA) test strips that often use gold nanoparticles (AuNPs) or quantum dots (QDs) as colored labels for signal amplification, as well as some commercial goods with nanoformulations used in agriculture. For the commercialization of nano-based assays (nanosensors), nanodisks (nanoparticles-based artificial sensing), and that may be used as point-of-care testing (POCT) devices for mycotoxin detection, it will be necessary to conduct additional research and make additional investments to overcome the difficulties identified.
Fabrication of green nanomaterials
2023 - THIPE, VELAPHI C.; FREITAS, LUCAS F.; LIMA, CAROLINE S.A.; BATISTA, JORGE G.S.; FERREIRA, ARYEL H.; OLIVEIRA, JUSTINE P.R. de; BALOGH, TATIANA S.; KADLUBOWSKI, SLAWOMIR; LUGAO, ADEMAR B.; KATTI, KATTESH V.
The purpose of this chapter is to discuss the production of biocompatible green nanomaterials for biomedical applications using green nanotechnology. To enhance drug loading and delivery, these nanomaterials are engineered with immunomodulatory ligands such as phytochemicals (Epigallocatechin gallate, Mangiferin, Resveratrol), proteins (albumin and papain), crosslinked hydrogels, and nanogels. The nanomaterials described herein are synthesized via redox potential of electron-dense phytochemicals that reduce metallic precursors to their stable corresponding nanoparticles and via water radiolysis with ionizing radiation as a green approach (due to the absence of any reducing agent) for use as radiosensitizers (albumin and papain nanoparticles) in nuclear medicine – theranostics applications. The phytochemicals facilitate the delivery of nanoparticles through receptor mediated endocytosis, while the proteins such as papain, due to their proteolytic action enhances the permeation of nanoparticles into tumor tissue, and albumin increase the pharmacokinetic efficiency of these nanoparticles. The nanoparticles developed have shown effectiveness against a variety of human cancers while posing no toxicity to normal tissue. Additionally, a pilot human clinical combing Ayurvedic medicine with green nanomedicine is given as a novel approach for treating breast cancer and other related illnesses. Finally, the importance of ecotoxicology for nanomaterials is discussed in order to provide safety data in relevant multiple species (fish, daphnia, algae, rodents, etc.) with paratope/epitope distributions for evaluating tissue cross-reactivity profiles in human tissues and to provide critical information on in vivo toxicity in order to predict the possible adverse effects of nanomaterials on human and environmental health as an effort to establish regulatory limits and ISO standards for nanomaterials.
In situ characterization of NORM waste from the oil industry
2022 - DELLAMANO, J.C.; DAMATTO, S.R.; CARVALHO, R.N.; MENEGHINI, A.A.; MARUMO, J.T.; MADUAR, M.F.; VICENTE, R.
In the oil industry, radioactive wastes are generated in the oil production platforms containing natural radionuclides, such as 226Ra and 228Ra, the NORM waste. This waste is mainly in the form of produced water, sludge and scales which should be characterized for the correct final destination. The Brazilian laws establish that the NORM wastes from the oil production must comply with Law 10308 of November 20, 2001, which determine in its article 7, "The disposal of radioactive waste of any kind in the oceanic islands, the continental shelf and the Brazilian territorial waters is prohibited." Therefore, the NORM waste from offshore oil extraction rigs should be transported to onshore facilities. There are two options for the destination of this material: industrial landfill, in the case of activity concentrations are below clearance limits established by Brazilian Nuclear Commission, CNEN; or on the contrary, to intermediate storage facilities, until final disposal is decided. Currently, the oil production companies take samples from the waste and send them to radiometric laboratories in order to evaluate their activity concentration by gamma spectrometry. The complete process takes more than six months to be concluded. Nuclear and Energy Research Institute, IPEN, is making efforts to solve the management problems of NORM waste from oil extraction, including conduct research aiming at characterizing the waste. The objective of the paper is to present the results of in situ characterization of drums containing oil sludge using portable gamma spectrometers.
Ótica e Fotônica
2011 - FREJLICH, JAIME; VIANNA, SANDRA; DAVIDOVICH, LUIZ; KHOURY, ANTONIO Z.; WETTER, NIKLAUS U.
Física Médica
2011 - BAFFA FILHO, OSWALDO; ZEZELL, DENISE M.; COSTA, PAULO R.; SILVA, ANA M.M. da; FREITAS, MARCELO B. de
Neodymium doped lithium yttrium fluoride (Nd:YLiF4) lasers
2013 - WETTER, N.U.
As a laser material, the neodymium doped lithium yttrium fluoride laser shows some very important and favorable characteristics when it comes to laser beam quality, efficient high-energy pulsed operation and parametric processes, amongst other applications. In this chapter we will discuss several approaches that have resulted in efficient, high-quality laser beams usually through decreasing the influence of the structural drawbacks of the YLF host whilst taking advantage of its favorable optical properties.
Gestão da inovação sustentável
2022 - KIBRIT, EDUARDO; MACHADO, ROGERIO J.; KRUGLIANSKAS, ISAK
Design bases for automation of a quality assurance system in radioactive waste management
2021 - SMITH, RICARDO B.; VICENTE, ROBERTO
The design, construction, operation and decommissioning of a radioactive waste management facility requires compliance with the applicable regulations for nuclear quality assurance. However, although compliance is mandatory, in some countries the requirements are outlined for every type of nuclear facility, therefore they are generic and lack details of the actions necessary to ensure that the more specific quality objectives for a radioactive waste management facility are met. Besides that, the quality assurance system of such enterprise is complex, but ready-to-use, commercially available computer tools to assist managing the processes are still needed. The available quality management software requires either adaptation through the inclusion of specific data sets from the quality control program of a radioactive waste management facility, or the development of a customized tool. Therefore, the objective of this work is to search for a brief historical background of the emergence of Quality Assurance in the nuclear area in the Western world, providing information to form the engineering bases that allow the development of a computerized quality assurance system that may assist the quality manager to assure compliance with the applicable regulation in these countries.
Antifragility and radioactive waste management
2021 - SMITH, RICARDO B.; TESSARO, ANA P.G.; MARUMO, JULIO T.; VICENTE, ROBERTO
It is not possible to quantify the future, since it is unknown to us. Mathematical models fail when the ambiguity of facts overrides them. Nevertheless, the traditional risk management, with its difficulty in predicting elements that challenge the linear thinking, has in recent years had a strong partner: Antifragility. Unlike disciplines that seek to mitigate the risks of the unpredictable, antifragility views uncertainty as desirable and necessary. It is a recent discipline that breaks the paradigm of always being more effective and efficient; instead, the focus is on the fragile points of an institution, and how to incorporate in it the ability to get stronger over time, as it is subject to stress. Decision making is ultimately a bet. And when it comes to strategic decisions, these are usually high-risk bets because they financially affect the organization, or even the safety of a group, a city, or a country. And the vast majority of decisions are increasingly being made in situations without the full picture of a defined causal model being available. In the case of the nuclear area, it is a field of intense control due to the risk of excessive radiological exposure, and as such it requires a rigorous and continuous risk management, including the management of radioactive waste which is produced in its most various fields of action. Based on this approach, this work seeks to analyze possible fragilities in the institutional, staff and technological areas of the Radioactive Waste Management Service of the Nuclear and Energy Research Institute, in the city of São Paulo, and therefore present potential solutions under the perspective of antifragility, aiming at improving the safety of the human being and the environment.
Determination of potassium-40 in some beer styles
2021 - SMITH, RICARDO B.; VICENTE, ROBERTO; CHEBERLE, LUAN T.V.; ROSA, MYCHELLE M.L.
The radiation from radioactive isotopes of the natural radioactive series of thorium (Th-232) and uranium (U-238 and U-235), as well as radioactive potassium (K-40), are the major contributors of natural terrestrial radiation. The K-40 is a radionuclide that occurs naturally in a fixed ratio with the stable potassium. Potassium is an essential element for humans and its concentration in the body is controlled by metabolic processes. Beer is a highly widespread drink and is consumed worldwide. One of the great characteristics of the variety of beers, in their styles, is the possibility of using innumerable ingredients in their production, such as different fruits, seasonings, leaves and roots, grains, malts and hops, and the choice of ingredients can interfere directly in their properties. The present study presents the K-40 determination in beers with different styles applying the technique of analysis by gamma spectrometry. Reference material IAEA-327-Soil was analyzed for validation of the methodology. The results differ mainly due to the different raw materials used in the beer production.
Plutonium-238
2021 - SMITH, RICARDO B.; VICENTE, ROBERTO; ROMERO, FERNANDA
Plutonium-238 is currently still the best fuel to power satellites to be sent to deep space in regions where the solar panels can no longer efficiently receive the sunlight. For 50 years, the National Aeronautics and Space Administration (NASA) has used this radioisotope as a fuel in radioisotope thermoelectric generators (RTGs) installed on satellites such as Pioneer 10 and 11, Voyager 1 and 2, Cassini-Huygens and New Horizons, as well as the various rovers sent to the Moon and to Mars, among others. Plutonium-238 is not a naturally occurring isotope on the planet, it was produced in greater quantity during the Cold War period, as a byproduct of the production of Plutonium-239 used for nuclear bombs. However, after the shutting down of the Savannah River reactors in 1988 and the ending of the Soviet Union in 1991, the United States stock of Plutonium-238 has been increasingly reduced, which threatens NASA’s future space projects. Commentaries on the options available to the United States, from restarting the production of this fuel, to possible alternatives for a new type of fuel or equipment that may supply the spacecrafts, are also presented.
Knowledge management in the decommissioning of nuclear facilities in Brazil
2021 - SMITH, RICARDO B.; SALVETTI, TEREZA C.; TESSARO, ANA P.G.; MARUMO, JULIO T.; VICENTE, ROBERTO
In the second half of the twentieth century in Brazil, several nuclear facilities were built for the most varied objectives. The largest number of such facilities is at the Nuclear and Energy Research Institute in São Paulo (IPEN-CNEN/SP). For different reasons, some of these facilities had their projects finalized and were deactivated. Some of the equipment was then dismantled, but the respective nuclear and radioactive material remained isolated in the original sites awaiting the proper decommissioning procedures. The Celeste Project is an example of a facility where the nuclear material has been kept, and is subject to Argentine-Brazilian Agency for Accounting and Control of Nuclear Materials (ABACC) periodic inspections. Because of a number of interests, including financial and/or budgeting situations at the institutions, decades have passed without any further action, and the people who withhold information and knowledge about these facilities have already moved away from the area or are in the process of. Therefore, this work proposes an analysis about the knowledge management reflecting on the possible consequences for the decommissioning processes, in case of loss of the knowledge acquired.
Advanced Heavy Water Reactor
2021 - SMITH, RICARDO B.; VICENTE, ROBERTO; SACHDEVE, MAHIMA; BISURI, INDRANIL
One of the great advances in the current evolution of nuclear power reactors is occurring in India, with the Advanced Heavy Water Reactor (AHWR). It is a reactor that uses thorium as part of its fuel, which in its two fueling cycle options, in conjunction with plutonium or low enriched uranium, produces energy at the commercial level, generating less actinides of long half-life and inert thorium oxide, which leads to an optimization in the proportion of energy produced versus the production of burnt fuels of the order of up to 50%. The objective of this work is to present the most recent research and projects in progress in India, and how the expected results should be in compliance with the current sustainability models and programs, especially “Green Chemistry”, a program developed since the 1990s in the United States and England, which defines sustainable choices in its twelve principles and that can also be mostly related to the nuclear field. Nevertheless, in Brazil, for more than 40 years there has been the discontinuation of research for a thorium-fueled reactor, and so far there has been no prospect of future projects. The AHWR is an important example as an alternative way of producing energy in Brazil, as the country has the second largest reserve of thorium on the planet.
Further analyses of the unburied Goiania accident packages
2021 - SMITH, RICARDO B.; TESSARO, ANA P.G.; ROLINDO, NATALIE C.; VICENTE, ROBERTO
In 1987, in the city of Goiania, Brazil, a derelict teletherapy machine was disassembled by scavengers and Cs-137 was released in the environment, unleashing the biggest radiological accident in Brazil. During the 15 days before the accident was acknowledged, some contaminated materials were sold and delivered to recycling factories in a few cities in the state of Sao Paulo, Brazil, in the form of metal scrap and recycled paper bales. The contaminated material was then collected, the metal scrap was conditioned in forty-three 200-liter drums, and the paper bales were stored in fifty 1.6 cubic meter steel boxes at the interim storage of the Nuclear and Energy Research Institute (IPEN), in the city of Sao Paulo, and there remained ever since. In 2017, 30 years later, initial analyses were performed at a sample of these boxes, checking for their activity, weight, and incongruences between the original values recorded at the time of collection and the measurement results 30 years later. The results indicated that none of the boxes checked were close to the clearance limit and that, without any sort of treatment, this radioactive waste should be stored for at least 150 years more. Visual inspection could not be performed at that time. Nowadays, some of the boxes were opened and samples from the contaminated material inside were taken for analysis. The main objective of this work is to report the results from the evaluation of the physical state of this material. After these analyses, the treatment options for volume reduction that were previously proposed were reviewed, and the method that best suits the current characteristics of the waste was chosen.
Opening the Goiânia accident unburied waste packages
2021 - TESSARO, ANA P.G.; GERALDO, BIANCA; SOUZA, DAIANE C.B. de; SMITH, RICARDO B.; VICENTE, ROBERTO
The year 2017 marks 30 years since the radiological accident in Goiânia, Brazil, which resulted from the leakage of Cs-137 from a teletherapy equipment. The contaminated material collected during the response to the accident was disposed of in Abadia de Goiás, about 20 km from Goiânia. However, in the initial 15-day period before the authorities were notified, contaminated paper bales and scrap metal were sold and transported to material recycling facilities in the State of São Paulo, one thousand kilometers away. These materials were later collected in steel boxes and drums, and stored in the intermediate waste storage facility of the Nuclear and Energy Research Institute - IPEN, in São Paulo. The objective of this paper is to describe the work performed to check the present condition of the paper bales waste boxes, reassess the reported Cs-137 activities, and evaluate possible treatment methods that can be applied to reduce the volume of waste. Prospective waste treatment methods are discussed.

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