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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Determination of ³⁶Cl and other long-lived radionuclides in decommissioning concrete wastes

Ashton, Linda January 2000 (has links)
The decommissioning of nuclear power stations will lead to the production of a number of contaminated components. The materials produced will consist of process and structural wasteforms. Before this waste can be disposed it will be necessary to obtain a full inventory of those radionuclides contained in those wastes. This will be necessary to ensure that the waste is handled in a suitable manner and that full information is available so that reliable risk assessment can be carried out on the proposed disposal site. A number of radionuclides have been highlighted as significant in terms if their halflife, terrestrial mobility and predicted levels in decommissioning wastes. A selection of these radionuclides have been investigated, and methods developed for their determination in concrete. It was a requirement of this work that the methods developed were robust and that the minimum detectable amount was below that of the de minimis of O.4Bq g-1.
12

The isotopic composition of lead in man and the environment in Finland isotope ratios of lead as indicators of pollutant source /

Keinonen, Marja. January 1989 (has links)
Thesis (doctoral)--University of Helsinki, 1989. / Includes bibliographical references (p. 92-101).
13

Determinacao de sup210 Pb e 210 Po em amostras marinhas e aerossois

SAITO, ROBERTO T. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:40:57Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:22Z (GMT). No. of bitstreams: 1 04019.pdf: 3977762 bytes, checksum: 21b56916c7935f0514332dff16138d5b (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
14

Estudo comparativo entre metodologias de cromatografia planar para controle radioquímico de radiofármacos de tecnécio-99m / Comparison study among methodologies of planar chromatography for radiochemical control of sup(99m)Tc radiopharmaceuticals

MONTEIRO, ELISIANE de G. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:35:28Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:34Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
15

Determinacao de sup210 Pb e 210 Po em amostras marinhas e aerossois

SAITO, ROBERTO T. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:40:57Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:22Z (GMT). No. of bitstreams: 1 04019.pdf: 3977762 bytes, checksum: 21b56916c7935f0514332dff16138d5b (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
16

Estudo comparativo entre metodologias de cromatografia planar para controle radioquímico de radiofármacos de tecnécio-99m / Comparison study among methodologies of planar chromatography for radiochemical control of sup(99m)Tc radiopharmaceuticals

MONTEIRO, ELISIANE de G. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:35:28Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:34Z (GMT). No. of bitstreams: 0 / Os radiofármacos são substâncias que possuem radioisótopos em sua composição. Cerca de 95% dos procedimentos realizados em medicina nuclear faz o uso de radiofármacos com finalidade diagnóstica, sendo os reagentes liofilizados (RL) marcados com Tecnécio-99 meta estável (99mTc), obtido a partir de um gerador de 99Mo/99mTc, os mais utilizados. O controle de qualidade representa o conjunto de ensaios a serem realizados para certificar que o produto é adequado ao propósito. Um aspecto importante a ser avaliado nos radiofármacos de 99mTc é a pureza radioquímica (% PRq) para quantificação de pertecnetato livre (99mTcO4 -) e tecnécio coloidal (99mTcO2), principalmente por cromatografia em papel (CP), em camada delgada (CCD) e cromatografia líquida de alta eficiência (CLAE). O objetivo deste trabalho foi realizar a comparação das metodologias de controle radioquímico de RL marcados com 99mTc descritas nas farmacopéias americana (FA) e europeia (FE) com aquelas utilizadas no IPEN. O eluído de 99mTcO4 e os RL: DISIDA, DMSA, DTPA, EC, ECD, GHA, MIBI, MDP, PIRO, SAH e Sn Coloidal foram provenientes do IPEN-CNEN/SP. Foram utilizados os suportes cromatográficos TLC-celulose, TLC-SG,TLC-SG fase reversa, HPTLC-celulose e HPTLC-SG da Merck e ITLC-SG da Pall Corporation, W1MM, W3MM, W17M e W31ET da Whatman. A contagem da radioatividade foi feita em contador gama Perkin Elmer modelo Cobra D-5002. A marcação dos RL foi feita de modo a obter concentração radioativa de 55,0 MBq mL-1 (1,5 mCi mL-1). Foram determinadas as %99mTcO4 -, %99mTcO2 e % PRq até 4 horas de marcação. Dos 11 RL, apenas EC e GHA não possuem método de controle radioquímico na FA e FE. Na FA e/ou na FE, os métodos para DTPA, MDP, PIRO, SAH e Sn Coloidal utilizam ITLC-SG; no IPEN, este suporte cromatográfico é utilizado em DISIDA, EC, ECD, GHA, PIRO, MIBI e SAH. Devido à descontinuidade na fabricação de ITLC-SG (recomendado em 40, 70 e 41% das metodologias da FA, FE e IPEN, respectivamente), foi necessário buscar alternativas para sua substituição no controle radioquímico, avaliando-se suportes do tipo HPTLC (celulose e sílica gel) e Whatman (com diferenças de espessura e fluxo de corrida). Os resultados de % PRq determinada pelos métodos descritos na FA, FE, IPEN e os demais sistemas avaliados que apresentaram coeficiente de variação menor que 5% não foi considerada diferença significativa entre os métodos. Os sistemas cromatográficos avaliados neste trabalho podem ser utilizados em substituição ao suporte ITLC-SG. O HPTLC-celulose foi o suporte que apresentou tempo de análise, perfil cromatográfico e custo semelhante ao ITLC-SG, tornando-o um dos suportes mais indicados a ser utilizado como alternativa ao ITLC-SG nos 11 RL avaliados. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
17

Evaluation and Application of Radiochemical Neutron Activation to Noble Metal Analysis

Evans, Noreen J. 05 1900 (has links)
<p> A rapid and simple radiochemical neutron activation technique involving tellurium coprecipitation of Au, lr, Pd and Pt was evaluated using the U.S.G.S. standards PCC-1 (peridotite) and DTS-1 (dunite) as well as a house standard, JHC-6 (spinifex zone of a komati itic peridotite). It was then applied to the analysis of samples of Archean greenstone from the Red Lake area.</p> <p> The technique gives detection limits of 0.01-0.02, 0.02, 0.1-0.4 and 1-2 ppb for Au, Ir, Pd and Pt respectively and precisions of <25-35%. The method can be successfully applied to the analysis of PGE levels in sulphur-poor rocks, and large numbers of samples can be processed in a short period of time.</p> <p> A comparison of PGE content between several types of mafic rocks was made as well as an investigation of possible secular trends (Archean vs. Phanerozoic) in PGE concentration.</p> / Thesis / Master of Science (MSc)
18

Radioisotope laboratory safety auditing, compliance and associated problems in NSW

Bartolo, William Charles Francis, Safety Science, Faculty of Science, UNSW January 2007 (has links)
This thesis reports on the modification of the "Safecode" computer-program to monitor the safety of radio-isotope laboratories, and its application to 24 compliance audits in NSW during the period 1999 to 2006. Additionally, an attempt was made to predict the level of risk to persons working within those laboratories. Based on the current NSW radiation control legislation and the relevant Australian Standards a comprehensive audit checklist was developed for this project. Each safety requirement in those documents was used to develop a question, resulting in 187 questions in the checklist. The questions were grouped into the following seven Topic Elements: Licensing and Registration; Radiation Safety Administration; Personal and Area Monitoring; Dose Limit Compliance; Documentation/Records; RSO/RSC Qualifications and Duties; and Facilities. A novel feature was the allocation of "weighting factors" to individual questions and Elements. The computer program facilitated analysis of data and provided output in spreadsheet and graphical form. .The on-site physical audits were conducted using the project check-list, and were supplemented by discussions with the client's representative. The results showed significant variation between sites with overall compliance scores ranging from 37% to 94%. The reasons for this large variation stem from differences in local management regime; the appointment of an RSO at one site; variation in the extent of adoption of relevant codes of practice; and legislative weaknesses. Further analysis of the data presented legal, advisory and combined scores for each Element for each site; and variations over time. The graphic displays of the results were appreciated by client management. The formula developed to predict risk, based on the physical parameters alone, showed little relationship to the total audit scores. Statistical analysis of the two data groups by correlation coefficient confirmed this general finding. Development of the formula however served to indicate deficiencies in the Question Set, and the importance of human factors in achieving a high degree of safety.
19

Radioisotope laboratory safety auditing, compliance and associated problems in NSW

Bartolo, William Charles Francis, Safety Science, Faculty of Science, UNSW January 2007 (has links)
This thesis reports on the modification of the "Safecode" computer-program to monitor the safety of radio-isotope laboratories, and its application to 24 compliance audits in NSW during the period 1999 to 2006. Additionally, an attempt was made to predict the level of risk to persons working within those laboratories. Based on the current NSW radiation control legislation and the relevant Australian Standards a comprehensive audit checklist was developed for this project. Each safety requirement in those documents was used to develop a question, resulting in 187 questions in the checklist. The questions were grouped into the following seven Topic Elements: Licensing and Registration; Radiation Safety Administration; Personal and Area Monitoring; Dose Limit Compliance; Documentation/Records; RSO/RSC Qualifications and Duties; and Facilities. A novel feature was the allocation of "weighting factors" to individual questions and Elements. The computer program facilitated analysis of data and provided output in spreadsheet and graphical form. .The on-site physical audits were conducted using the project check-list, and were supplemented by discussions with the client's representative. The results showed significant variation between sites with overall compliance scores ranging from 37% to 94%. The reasons for this large variation stem from differences in local management regime; the appointment of an RSO at one site; variation in the extent of adoption of relevant codes of practice; and legislative weaknesses. Further analysis of the data presented legal, advisory and combined scores for each Element for each site; and variations over time. The graphic displays of the results were appreciated by client management. The formula developed to predict risk, based on the physical parameters alone, showed little relationship to the total audit scores. Statistical analysis of the two data groups by correlation coefficient confirmed this general finding. Development of the formula however served to indicate deficiencies in the Question Set, and the importance of human factors in achieving a high degree of safety.
20

Estudo e levantamento de parâmetros para montagem de um laboratório de produção de fontes radioativas utilizadas na verificação de equipamentos / Study and survey of assembling parameters to a radioactive source production laboratory used to verify equipments

Gauglitz, Érica 29 March 2010 (has links)
Este trabalho apresenta o levantamento de parâmetros para implementação adequada e segura de pisos, portas, janelas, bancadas, capelas entre outros, de um laboratório radioquímico. A disposição de cada item segue orientações de guias, normas nacionais da Comissão Nacional de Energia Nuclear (CNEN) e internacional da Agencia Internacional de Energia Atômica (IAEA), com objetivo de garantir a proteção radiológica do trabalhador e do ambiente. A disposição adequada dos itens do laboratório radioquímico, garante a qualidade e segurança na produção de fontes radioativas seladas de 57Co 137Cs e 133Ba com atividades 185, 9.3 e 5.4 MBq respectivamente. Estas fontes são utilizadas na verificação de medidores de atividade, equipamento que todo Centro de Medicina Nuclear deve ter disponível segundo recomendações da norma CNEN-NN-3.05 Requisitos de Radioproteção e Segurança para Serviços de Medicina Nuclear para verificação da atividade de radiofármacos que serão administrados nos pacientes para fins de diagnóstico e terapia. Um medidor de atividade fora adquirido pelo laboratório de produção de fontes, com o qual foram realizados os testes de precisão, exatidão, reprodutibilidade e linearidade, que devem apresentar resultados dentro dos limites estabelecidos na norma CNEN-NN-3.05. / This paper presents a survey of parameters for the proper and safe flooring, doors, windows, fume hoods and others, in a radiochemical laboratory. The layout of each item follows guidelines and national standards of the National Commission of Nuclear Energy (CNEN) and the International Atomic Energy Agency (IAEA), aiming to ensure the radiological protection of workers and environment. The adequate items arrangement in the radiochemical laboratory ensures quality and safety in the production of 57Co 137Cs and 133Ba radioactive sealed sources, with activities 185, 9.3 and 5.4 MBq, respectively. These sources are used to verify meter activity equipment and should be available throughout the Nuclear Medicine Center, following the recommendations of CNEN-NN-3.05 standard \"Requirements for Radiation Protection and Safety Services for Nuclear Medicine\", to verify the activity of radiopharmaceuticals that are administered in patients, for diagnosis and therapy.

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