Caracterização da radioatividade das águas do aquífero Guarani

This research aimed to evaluate the quality of “Aquifer Guarani’s” waters in the context of the current legislation related to the radioactive aspects, besides correlating the values obtained with chemical data already available, seeking to make an integrated analysis of the data in order to establish possible tendencies with directions of underground flow. The determinations of the total radioactivity beta and alpha were accomplished through the employment of the available infrastructure at the LABIDRO – Laboratory of Isotope and Hydrochemistry of the Petrology and Metallogeny of UNESP’s Institute of Geosciences and Exact Sciences, largely implanted through resources supplied by FAPESP and CNPq. The systems were gauged for the determinations of interest with tracer of known activity. Preliminaries tests were accomplished with high radioactivity samples of water to check the applicability of the methods. It was ended that the waters analyzed possess low radioactivity, as much alpha as total beta, and, therefore, they are appropriate for the human consumption; that there is not lineal relationship between the obtained data and the chemical data already available; and that the direction of the underground flow of the Aquifer doesn't check any tendency to the generated data.

Radioatividade e hidroquímica em águas subterrâneas do município de Botucatu (SP)

The main objective of this study is to determine the activity of Po-210, Pb-210 and gross alpha/beta radioactivity in groundwater collected in Botucatu, municipality of the São Paulo state, Brazil. Samples were collected in wells to perform the radiochemical analysis. Most wells are registered in DAEE, Sabesp or CPRM. The activity of polonium was obtained by the method of alpha spectrometry, held in LABIDRO at UNESP, Rio Claro. All samples showed radioactivity values below the maximum allowed by WHO, that are: gross alpha radioactivity = 0,5 Bq/L, gross beta radioactivity = 1,0 Bq/L, Po210 = 0,2 Bq/L and Pb210 = 0,1 Bq/L. The results of hydrochemical analysis were compared with the 1469 Ordinance of the Health Ministry, and all values are bellow the maximum allowed. The data also allowed obtain the samples classification using the Piper diagram. The samples AAB, Quinta do Manacás, Faz. Quatro Irmãs, Sesi, Sitio São José and ITE are classified as calcic bicarbonate; the samples Staroup and Caio are potassic; the samples Banespa and BTC are bicarbonate and mixed interms of dissolved cations; Sitio das Palmeiras sample is sodium bicarbonate; the sample Faz. São Paulo is chlorinated calcic; the sample Sítio Btu-Pardinho chlorinated and mixed interms of dissolved cations

Ensino do conceito de radioatividade utilizando a biografia de Marie Curie

Como objetivo de pesquisa esta monografia buscou coletar dados descritivos que permitissem esclarecer as possibilidades educativas para o ensino de química em uma abordagem contextual utilizando história e filosofia da química e da ciência. Esta monografia trata de uma intervenção feita dentro do cronograma de aulas de uma escola pública de Bauru, em que se buscou levar informações que possibilitassem uma abertura na perspectiva de vida de alunos que estudam e/ou vivem em meio a violência social e doméstica. A intervenção consistiu no estudo da história da descoberta da radioatividade, ensinada através da biografia de Marie Curie, a mulher que denominou o fenômeno dos raios invisíveis de radioatividade, em sua tese de doutorado. Ela também descobriu, por meio da mesma pesquisa que fundamentou a referida tese, dois elementos radioativos, o polônio e o rádio. Para o planejamento da pesquisa e a análise dos dados se utilizou a metodologia qualitativa de pesquisa, com enfoque na pesquisa-ação e técnicas de análise de conteúdo. Para a aplicação dessa aula foi elaborada uma atividade envolvendo história da química e das ciências naturais dentro de uma atividade de leitura. Utilizou-se o livro GÊNIO OBSESSIVO: O MUNDO INTERIOR DE MARIE CURIE de Bárbara Goldsmith como base para os textos utilizados em aula. Foi utilizado o livro MARIE CURIE E A BUSCA PELO RÁDIO de Beverly Birch, como fonte de ilustrações. Essas ilustrações, assim como outras imagens extraídas da internet, foram utilizadas para relacionar os fatos ocorridos durante a pesquisa de Marie, realizada com o auxílio do marido Pierre Curie, que era professor e pesquisador em física e trabalhava com fenômenos relacionados a piezeletricidade, entre outros fenômenos eletromagnéticos. A aula consistiu na aplicação de um questionário inicial para averiguar as idéias prévias que os alunos apresentavam sobre a radioatividade e o contexto...

Titia vem cá ver a pedra alumiante que o papai trouxe'. História da Ciência, Radioatividade e o Césio-137 em Goiânia: propostas para uma unidade didática

This study aimed to discuss the recent contributions of History of Science to theteaching of chemistry. The theme of the teaching unit was on the accident of cesium-137 in Goiânia ? Goiás, Brazil (1987). This was a qualitative study in which researcherand professor use the methodology of teaching on research. Thus, students should seekinformation, organize the data collected and establish relationships. Students producedposters in an exhibition at the school on the twentieth anniversary of the accident.Results demonstrated the importance of this resource. It was possible to exploit theabundance of detail and illustrations utilized what themes they students considerimportant and which they exploited. A poster exhibition on the theme indicated thestrong interest of students to participate in all activities proposed. The study alsorevealed the importance of using elements of the History of Science in ChemicalEducation and its relationship to the daily life of students.Key words: history of science; radioactivity; cesium-137

Dose de exposição radiométrica e composição das rochas sedimentares e ígneas na bacia do Rio Corumbataí (SP)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Caracterização radiométrica de ácidos fosfóricos e seus produtos industriais

The addition of phosphoric acids and their (by)products became a common practice in areas like metal treatment, detergent production, water and effluent treatment, as well by food, beverage and pharmaceutical industries. The phosphoric acids exhibit different radionuclides activity concentration, being important to evaluate the implications for the human and animal health. The 238U concentration in almost all raw acid phosphoric are within the worldwide range and the mean exposure rate for the filtration cake is 10 nGy/h, which is mainly attributed to 40K. The results obtained for total and (bio)available uranium concentration in filtration cake indicate that only 40% is (bio)available for plants. The radionuclides present in phosphoric acid food grade and filtration cake do not raise their concentration in human food chain or soils to harmful levels, consequently, not offering hazard to the ecosystem and animal or human health.

Uso do Rad7 para a caracterização do torônio em águas de estâncias hidrominerais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo hidroquímico e radiométrico do aquífero Bauru em São José do Rio Preto (SP)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Emanação de radônio em rochas ornamentais e para revestimento do estado do Ceará, Brasil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relações entre produção de biogás em aterro sanitário e variações no potencial elétrico natural

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Aplicação dos princípios de radioproteção em medicina nuclear

The Nuclear Medicine is a medical specialty which uses different radioisotopes for diagnostic and therapeutic purposes. The isotopes are radioactive elements which are administered in vivo and present distribution to specific organs or cell types. The knowledge of radioactivity and notions related to ionizing radiation allow to contextualize the radiological protection measures to be taken in Nuclear Medicine. So it is possible to minimize unnecessary exposure to patients, the public, and individuals occupationally exposed and the environmental. For this it is necessary to relate the physical and technological bases apply to this mode with the standards established by regulatory agencies, including the CNEN (National Nuclear Energy Commission) and ANVISA (National Agency for Sanitary Vigilance). In this scenario, it is important that the theoretical endorse the activities which are periodically audited for verification of compliance with the standards that aim to radioprotection. One role of the Medical Physicist in these services is, therefore, act as Radiation Protection Supervisor exerting numerous activities and ensuring compliance with these standards. In this context the stage in the area of Nuclear Medicine was developed in many customers of the enterprise Rad Dimenstein & Associados LTDA, among them the hospitals Israelita Albert Einstein (HIAE), Nossa Senhora de Lourdes (HNSL), Santa Paula (HSP), Cruz Azul (CRAZ), Grupo Fleury, among other clinics. Following the routine and then carrying out various activities pertaining to the Medical Physicist in the area, it was noted that the measures and actions are extremely effective and fundamental in terms of radiological protection

SPECT (Single photon emission tomography): Gama câmara, reconstrução tomográfica e características funcional

The SPECT (Single Photon Emission Computed Tomography) systems are part of a medical image acquisition technology which has been outstanding, because the resultant images are functional images complementary to those that give anatomic information, such as X-Ray CT, presenting a high diagnostic value. These equipments acquire, in a non-invasive way, images from the interior of the human body through tomographic mapping of radioactive material administered to the patient. The SPECT systems are based on the Gamma Camera detection system, and one of them being set on a rotational gantry is enough to obtain the necessary data for a tomographic image. The images obtained from the SPECT system consist in a group of flat images that describe the radioactive distribution on the patient. The trans-axial cuts are obtained from the tomographic reconstruction techniques. There are analytic and iterative methods to obtain the tomographic reconstruction. The analytic methods are based on the Fourier Cut Theorem (FCT), while the iterative methods search for numeric solutions to solve the equations from the projections. Within the analytic methods, the filtered backprojection (FBP) method maybe is the simplest of all the tomographic reconstruction techniques. This paper's goal is to present the operation of the SPECT system, the Gamma Camera detection system, some tomographic reconstruction techniques and the requisites for the implementation of this system in a Nuclear Medicine service

Sistema de Acelerador Linear Comercial para Radioterapia

This paper presents a study about the operation of the major system’s components of a linear particle acclerator (Linac). It addresses the components mainly responsible for the formation of the beam, through the inclusion of several block diagrams showing the details of the structure. Among the systems discussed may be mentioned the system modulator, automatic frequency control, dosimetry and auxiliary systems. The main objective is the dissemination of basic technology applied in linear accelerators and create literature about this subject in national language. Despite the high complexity and large number of devices that comprise a linear accelerator, it has been developed an easy to understand text that adresses the most relevant issues to the operation of the linear accelerator from the point of view of electrical engineering

Dosimetria ambiental do gás 222Rn: um exemplo de estudo das águas da região de Presidente Prudente – SP e considerações sobre abordagem do tema através do Banco Internacional de Objetos Educacionais – BIOE

Over the years, the concern with the detection of the levels of radionuclides in the environment has increased, given that they are carcinogenic to the human respiratory system. Present in the air, waters, soil and building materials, among other substances, radionuclides are unknown by most of the population. In this paper, we present the radioactive gas 222Rn, predominant element among all others and one way of detecting it in an example study of the waters of the Presidente Prudente - SP, through the plastic detector called CR-39. Likewise, we realized the need to approach this issue more broadly in schools and even in higher education, since this field of modern physics and environmental physics usually appears only in master's and doctorate. Thus, we attempted to perform the didactic transposition schooluniversity, through the construction of an object Educational, OE, to be placed on the Bank for International Educational Objects - bioethanol and by developing this contribute to the knowledge and understanding of the importance of monitoring of radioactivity in a way accessible to the population as a whole

Contaminação radioativa: aspectos fundamentais associados à poluição nuclear

Since its discovery, radioactivity has brought numerous benefits to human societies. It has many applications in medicine, serving as a tool for non-invasive methods for diagnosis and therapies against diseases such as cancer. It also applies to technologies for energy in nuclear power plants with relatively low impacts on terms of perfect security. All applications, however, have risks, requiring maximum caution to drive processes and operations involving radioactive elements because, once released into the environment, they have extremely harmful effects on organisms affected. This paper presents fundamental concepts and principles of nuclear physics in order to understand the effects of radioactive elements released into the environment, culminating on the issue of radioactive contamination. Literature review allowed us to understand the radioactive contamination problem on living beings. Three major nuclear accidents have happened in the last thirty years, two of them in consecutive years. The nuclear accident at Chernobyl, Ukraine, in 1986, polluted large areas, condemning hundreds of thousands of people to live with consequences of the accident and effects of radiation, killing thousands of people throughout the years. In 1987, a major radiological accident occurred in Goiania (GO) when a source of radioactive cesium was violated, leading to the death of those who had direct or indirect contact with cesium. The most recent accident, in March, 2011, was located at the nuclear power plant in Fukushima Prefecture, Japan, after an earthquake and tsunami hit the region. There is no extensive and accurate knowledge about the consequences of the contamination entailed in that accident, although it is possible to verify signals on a global scale. An analysis of reports of contamination of large areas generated by nuclear plants with release of hazardous wastes suggests it is necessary to rethink the energy matrix of the various countries...