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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.
131

Aktuelle Entwicklung in der Endlagerbranche

Lautsch, Thomas 28 September 2017 (has links) (PDF)
Die Endlagerbranche steht vor einem tiefgreifenden Wechsel. Die bisherigen Organisationseinheiten DBE mbH, ASSE GmbH, Bundesamt für Strahlenschutz (BfS) werden neu sortiert und in der neugegründeten Bundes-Gesellschaft für Endlagerung verschmolzen. Eine neue Genehmigungsbehörde, das Bundesamt für Kerntechnische Entsorgungssicherheit (BfE) wird geschaffen. Im Ergebnis dieser Neustrukturierung gibt es eine klare Aufgabentrennung zwischen Regulator und Operator. Darüber hinaus führt die Zusammenlegung der bisher verteilten Aufgaben vom Bauherr und ausführender Baufirma zu Synergieeffekten und einer größeren Umsetzungskompetenz in den Endlagerprojekten. Die neue Bundes-Gesellschaft für Endlagerung (BGE) wird sowohl in der Tiefe als auch in der Breite ihre Aktivitäten jede der bisher bestehenden Organisationen übertreffen und daher eine höhere Schlagkraft haben.
132

Creep Performance and Analysis of Buffer Material in a Nuclear Waste Disposal Vault

Yiotis, Demosthenes 08 1900 (has links)
No description available.
133

A Computer Simulation of the Operations of a Spent Nuclear Fuel Receiving and Storage Station

Barnard, Jeanna Lorene 01 July 1980 (has links) (PDF)
Spent nuclear fuel is received at a storage facility in heavily shielded casks transported by either rail or by truck. Once at the storage facility, the casks are inspected, emptied, decontaminated, and reshipped. Allied-General Nuclear Services' (AGNS) nuclear fuel reprocessing plant in Barnwell, South Carolina, is constructed but not yet licensed for spent nuclear fuel storage or reprocessing. Recently, however, AGNS was granted funds by the Department of Energy to prepare the necessary procedural and regulatory paperwork in order that the Fuel Receiving and Storage Station (FRSS) of the plant can be licensed by 1985. In this paper, the activities involved in the receiving an unloading of casks at the Barnwell FRSS is simulated by computer using IBM's program software package, General Purpose Simulation System (GPSS). The GPSS model is developed and verified, and steady-state output statistics are achieved. Also, several sensitivity analyses are performed such as, changes in expected arrival schedules and decision policies, and changes to the physical characteristics of the existing FRSS to monitor the effect of these changes in the existing system.
134

Environmental Aspects of the Nuclear Fuel Cycle and High-Level Radioactive Waste Disposal

Kent, Robert S. 01 April 1979 (has links) (PDF)
An assessment of the environmental effects of the nuclear fuel cycle industries is discussed, reactor waste inventory and standards are presented, and the alternatives for high-level radioactive waste disposal reviewed, with particular attention being given to disposal in deep geological formations on land. One of the major concerns regarding potential impacts of the nuclear fuel cycle industries is the lack of a definite and proven method of disposal of the high-level radioactive wastes from light water moderated reactors. The problem is expected to become more pressing as the nuclear power industry and the associated radioactive waste inventories grow in the strife to meet ever-increasing demands for energy. The current trend in waste management is towards reprocessing to recover unburned uranium and plutonium from spent reactor fuel and towards final disposal in deep geological formations (hard rock or salt) on land. Studies appear to support the viability of such a waste management and disposal concept for high-level radioactive wastes.
135

Signs of dangerdangerous signs : responding to nuclear threat

Van Wyck, Peter C. January 1997 (has links)
No description available.
136

Analysis by simulation of the disposition of nuclear fuel waste

Turek, Jeffery Lee January 1980 (has links)
To achieve the non-proliferation objectives of the United States, the reprocessing of spent nuclear fuel was discontinued in 1977. Since current at-reactor storage capacity is based upon a nuclear fuel cycle which includes reprocessing, this halt in reprocessing is causing large quantities of non-storable spent fuel. Permanent nuclear waste storage repositories will not be available until the end of the century. Present Department of Energy policy calls for sufficient interim Away-Prom-Reactor (AFR) Storage capacity to insure tilat no commercial reactor has to shut down due to inadequate storage space for discharged spent fuel. A descriptive simulation model is developed which includes all aspects of nuclear waste disposition. The model is comprised of two systems, the second system orchestrated by GASP IV. A spent fuel generation prediction module is interfaced with the AFR Program Management Information System and a repository scheduling information module. The user is permitted a wide range of options with which to tailor the simulation to any desired storage scenario. The model projects storage requirements through the year 2020. The outputs are evaluations of the impact that alternative decision policies and milestone date changes have on the demand for, the availability of, and the utilization of spent fuel storage capacities. Both graphs and detailed listings are available. These outputs give a comprehensive view of the particular scenario under observation, including the tracking, by year, discharge from every reactor. Included within the work is a review of the status of spent fuel disposition based on input data accurate as of August 1980. The results indicate that some temporary storage techniques (e.g., transshipment of fuel and/or additional at-reactor storage pools) must be utilized to prevent reactor shutdowns. These techniques will be required until the 1990’s when several AFR facilities, and possibly one repository, can become operational. / Ph. D.
137

Heat transfer and modelling studies for the analysis of waste storage facilities

Ramachandran, Subbaratnam. January 1985 (has links)
Call number: LD2668 .T4 1985 R33 / Master of Science
138

Desenvolvimento de metodologia para a caracterização de fontes radioativas seladas / Development of methodology for the characterization of radioactive sealed sources

Ferreira, Robson de Jesus 15 September 2010 (has links)
Fontes radioativas seladas são largamente empregadas no mundo. A Agência Internacional de Energia Atômica AIEA estima em dezenas de milhões de fontes radioativas no mundo. No Brasil, este número é próximo de 500 mil unidades, considerando-se as fontes de pára-raios e detectores de fumaça. Uma fonte selada pode tornar-se desnecessária, seja devido ao seu decaimento ou outro motivo, sendo classificada como fontes radioativas seladas fora de uso (FRS). No Brasil, a maioria das FRS é considerada rejeito radioativo e são encaminhadas a um dos institutos da CNEN. Sem uma estratégia definida para a deposição das FRS, estas são armazenadas aguardando uma solução. A Gerência de Rejeitos Radioativos - GRR do IPEN-CNEN/SP é o principal centro de recepção desse material e até meados de 2010 havia recebido cerca de 14.000 fontes. O processo proposto para a gestão dessas FRS consiste em retirá-las de suas blindagens originais e transferi-las a outra blindagem, projetada para esse fim. As operações de transferência são realizadas em uma cela quente, garantindo a segurança radiológica. Uma das exigências da CNEN é que todas as fontes seladas sejam caracterizadas. No processo estudado, a avaliação da atividade de cada fonte será feita utilizando-se um detector, do tipo câmara de ionização tipo poço. O presente trabalho tem por objetivo desenvolver uma metodologia para aferir ou determinar a atividade de FRS armazenadas na GRR de acordo com sua geometria e determinar suas incertezas. / Sealed radioactive sources are widely used in many applications of nuclear technology in industry, medicine, research and others. The International Atomic Energy Agency (IAEA) estimates tens of millions sources in the world. In Brazil, the number is about 500 thousand sources, if the Americium-241 sources present in radioactive lightning rods and smoke detectors are included in the inventory. At the end of the useful life, most sources become disused, constitute a radioactive waste, and are then termed spent sealed radioactive sources (SSRS). In Brazil, this waste is collected by the research institutes of the Nuclear Commission of Nuclear Energy and kept under centralized storage, awaiting definition of the final disposal route. The Waste Management Laboratory (WML) at the Nuclear and Energy Research Institute is the main storage center, having received until July 2010 about 14.000 disused sources, not including the tens of thousands of lightning rod and smoke detector sources. A program is underway in the WML to replacing the original shielding by a standard disposal package and to determining the radioisotope content and activity of each one. The identification of the radionuclides and the measurement of activities will be carried out with a well type ionization chamber. This work aims to develop a methodology for measuring or to determine the activity SSRS stored in the WML accordance with its geometry and determine their uncertainties.
139

Proposta de implantação de um sistema de gestão ambiental no laboratório de rejeitos radioativos do IPEN-SP / Proposal of implementation of environmental management system the laboratory of radioactive waste in IPEN-SP

Moura, Luiz Antonio Abdalla de 28 March 2008 (has links)
Constata-se, atualmente, um uso crescente da energia nuclear no Brasil, para geração de eletricidade e outras aplicações (na medicina, na indústria, em agricultura, em técnicas ambientais, em radio-esterilização). Na realização das atividades de pesquisa do ciclo do combustível nuclear, em outras atividades de pesquisa, nas atividades industriais de produção de combustível e de energia e em todas as aplicações da energia nuclear, são gerados rejeitos radioativos, de atividades alta, média ou baixa. Atualmente, existem técnicas adequadas e seguras para o tratamento e armazenagem desses rejeitos, comentadas neste trabalho e que, sendo aplicadas, facilitam a aceitação da energia nuclear pela Sociedade. Com a crescente preocupação com o meio ambiente, a Organização Internacional de Normalização preparou e emitiu a Norma ISO 14.001 - Sistemas de Gestão Ambiental, aplicável a todos os tipos e portes de organizações, visando a melhoria de seu desempenho ambiental. Seus requisitos foram detalhadamente comentados neste trabalho, sendo particularizados para a sua aplicação no Laboratório de Rejeitos Radioativos do IPEN, como um estudo de caso. / An increasing use of nuclear technology in the form of its several applications (electricity generation, medical, industrial, agricultural, environment and radiosterilization) is currently being observed in Brazil. Radioactive waste of high, medium or lower activity is produced in all fuel cycle and other research activities, industrial activities of fiiel production and electricity generation. Appropriate and safe technologies are available for the treatment and storage of radioactive waste and, when applied, contribute for the acceptance of nuclear energy by the Society. With the increasing importance of demands related to environmental issues, the International Organization for Standardization issued the Standard ISO 14.001 - Environmental Management System, applied to all types and size of organizations, helping them to increase their environment performance. In this research, the standard requirements were commented in detail, being particularized to the Laboratory of Radioactive Waste from IPEN, as a case study.
140

Desenvolvimento de metodologia para a caracterização de fontes radioativas seladas / Development of methodology for the characterization of radioactive sealed sources

Robson de Jesus Ferreira 15 September 2010 (has links)
Fontes radioativas seladas são largamente empregadas no mundo. A Agência Internacional de Energia Atômica AIEA estima em dezenas de milhões de fontes radioativas no mundo. No Brasil, este número é próximo de 500 mil unidades, considerando-se as fontes de pára-raios e detectores de fumaça. Uma fonte selada pode tornar-se desnecessária, seja devido ao seu decaimento ou outro motivo, sendo classificada como fontes radioativas seladas fora de uso (FRS). No Brasil, a maioria das FRS é considerada rejeito radioativo e são encaminhadas a um dos institutos da CNEN. Sem uma estratégia definida para a deposição das FRS, estas são armazenadas aguardando uma solução. A Gerência de Rejeitos Radioativos - GRR do IPEN-CNEN/SP é o principal centro de recepção desse material e até meados de 2010 havia recebido cerca de 14.000 fontes. O processo proposto para a gestão dessas FRS consiste em retirá-las de suas blindagens originais e transferi-las a outra blindagem, projetada para esse fim. As operações de transferência são realizadas em uma cela quente, garantindo a segurança radiológica. Uma das exigências da CNEN é que todas as fontes seladas sejam caracterizadas. No processo estudado, a avaliação da atividade de cada fonte será feita utilizando-se um detector, do tipo câmara de ionização tipo poço. O presente trabalho tem por objetivo desenvolver uma metodologia para aferir ou determinar a atividade de FRS armazenadas na GRR de acordo com sua geometria e determinar suas incertezas. / Sealed radioactive sources are widely used in many applications of nuclear technology in industry, medicine, research and others. The International Atomic Energy Agency (IAEA) estimates tens of millions sources in the world. In Brazil, the number is about 500 thousand sources, if the Americium-241 sources present in radioactive lightning rods and smoke detectors are included in the inventory. At the end of the useful life, most sources become disused, constitute a radioactive waste, and are then termed spent sealed radioactive sources (SSRS). In Brazil, this waste is collected by the research institutes of the Nuclear Commission of Nuclear Energy and kept under centralized storage, awaiting definition of the final disposal route. The Waste Management Laboratory (WML) at the Nuclear and Energy Research Institute is the main storage center, having received until July 2010 about 14.000 disused sources, not including the tens of thousands of lightning rod and smoke detector sources. A program is underway in the WML to replacing the original shielding by a standard disposal package and to determining the radioisotope content and activity of each one. The identification of the radionuclides and the measurement of activities will be carried out with a well type ionization chamber. This work aims to develop a methodology for measuring or to determine the activity SSRS stored in the WML accordance with its geometry and determine their uncertainties.

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