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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.
101

The Design Of An Out-Diffusion Experiment And The Use Of Geochemical Analyses For The Purpose Of Matrix Pore Fluid Extraction And Characterization: A Case Study For Radioactive Waste Disposal

Lambie, Katherine Elizabeth January 2008 (has links)
Deep crystalline rock formations of low permeability have been identified as a possible geological medium for high-level radioactive waste disposal. In order for the safe disposal of radioactive waste, a site characterization must be performed. A comparison of site characterization methods found out-diffusion methods to be the most viable technique for pore fluid extraction. Crush and leach, chemical and isotopic analyses such as, Cl-, 37Cl, 18O, 2H and 87Sr were valuable in characterizing the signature/origin of the pore fluids. Variations in the signatures of the pore fluids were observed and attributed to small differences in heterogeneity within the host rock and water to rock interactions. Estimates of the rate of effective diffusivity (De) were evaluated experimentally and with an analytical solution. Modelled De values were much greater than those determined experimentally, suggesting that the analytical solution provides a more conservative estimate of De for assessing radionuclide migration.
102

The Design Of An Out-Diffusion Experiment And The Use Of Geochemical Analyses For The Purpose Of Matrix Pore Fluid Extraction And Characterization: A Case Study For Radioactive Waste Disposal

Lambie, Katherine Elizabeth January 2008 (has links)
Deep crystalline rock formations of low permeability have been identified as a possible geological medium for high-level radioactive waste disposal. In order for the safe disposal of radioactive waste, a site characterization must be performed. A comparison of site characterization methods found out-diffusion methods to be the most viable technique for pore fluid extraction. Crush and leach, chemical and isotopic analyses such as, Cl-, 37Cl, 18O, 2H and 87Sr were valuable in characterizing the signature/origin of the pore fluids. Variations in the signatures of the pore fluids were observed and attributed to small differences in heterogeneity within the host rock and water to rock interactions. Estimates of the rate of effective diffusivity (De) were evaluated experimentally and with an analytical solution. Modelled De values were much greater than those determined experimentally, suggesting that the analytical solution provides a more conservative estimate of De for assessing radionuclide migration.
103

Kampanjmottagande : Hur tas Regionförbundet i Kalmar läns kampanj om slutförvar av använt kränbränsle emot av målgruppen?

Franzén, Jonas, Kautto, Jim January 2009 (has links)
Authors: Jonas Franzén and Jim Kautto Title: Information campaign analysis of the Region Council of Kalmar Counties public information campaign about final storage of radioactive waste. Level: BA Thesis in Media and Communication Studies. Key words: Campaign, Campaign analysis, final storage of radioactive waste, Region Council. Language: Swedish Content: The Regional Council of Kalmar County launched a campaign about final storage of radioactive waste in the spring of 2009. This study analyzes how that campaign was received by the target group. Theory: Following theories have been used in the study; theories of communication, planning of communication, public campaigns and receptions studies. Method: Methods used in this study is observing people passing the exhibition, asking questions to people passing the exhibition and two focus groups. We also asked questions to people riding the bus where the commercial was shown. Finally we got background information from two interviews with the creators of the campaign. Results: The campaign was launched based on a political decision. Despite that the decision was vague and that the Region Council was lacking a clear objective and measureable goals, the campaign still came out as a success. Since the objective with the campaign was to broaden the dialogue regarding final storage of radioactive waste, and make the public more informed about what could happen in Oskarshamn if the final storage comes there, the campaign succeeded in waken up some interest from the public opinion. The studies could not determine whether the campaign decreased the public's worries about the final storage of radioactive waste or not. Number of pages: 49 + appendix Program: Program for International Communication Location: University of Kalmar Institution: Institution of Communication and Design Period: Spring of 2009 Tutor: Sara Hamqvist Examiner: Britt-Marie Ringfjord
104

Effect Of Ionizing Radiation On Different Polymers And Possible Use Of Polymers In Radioactive (nuclear) Waste Management

Ozdemir, Tonguc 01 May 2006 (has links) (PDF)
In this study three polymers, namely poly(carbonate urethane), poly(bisphenol-a-epichlorohydrin) and poly(methyl methacrylate), were selected and change of properties with gamma treatment were studied. Two different dose rates were used for irradiations and the properties of the irradiated polymers exposed to same total absorbed dose were compared. In addition, long irradiations of up to about six months with high dose rate were done in order to understand the radiation stability of the polymers, which may be possible candidates for embedding media for low and intermediate level radioactive (nuclear) waste before their final disposal. Tensile, DSC, DMA, TGA, FTIR-ATR, FTIR tests were completed to understand the degradation of the polymers as a function of dose rate and total absorbed dose. The DSC and FTIR results showed that there was not much structural chemical changes in polymer chains with irradiation. However, the changes in mechanical properties were recorded. It was concluded that poly(carbonate urethane) and poly(bisphenol-aepichlorohydrin) can possibly be used in conditioning of radioactive waste, as they are radiation stable polymers. However, due to the moderate resistance of poly(methyl methacrylate) to ionizing radiation, it can be used for low level radioactive waste conditioning.
105

Design, optimization, and selectivity of inorganic ion-exchangers for radioactive waste remediation

Medvedev, Dmitry Gennadievich 01 November 2005 (has links)
The processes of development of nuclear weapons resulted in accumulation of thousands of curies of high-level radioactive waste. Liquid waste produced in the US has been stored in carbon steel tanks in highly alkaline (1-3 M NaOH, 6 M sodium salts) media for fifty years and leakage has occurred. One of the approaches to the solution of the problem of radioactive waste is to adsorb the nuclides on highly selective ion-exchange material, solidify in a glass matrix and dispose in a geological formation. The use of the ion-exchange technology is limited by the time of the sorbent-solution contact required to reduce the activity of the streams to acceptable levels. Inorganic ion-exchangers are promising materials due to their high radiation stability, extreme selectivity, and compatibility with the glass matrix. The contact time can be reduced by improving selectivities, kinetics, and capacities of the materials towards the target ions. This can be accomplished in part through understanding of the origin of ion-exchange selectivity. Crystalline zeotypes with minerals sitinakite (ideal formula Na2Ti2O3SiO4??2H2O) and pharmacosiderite (HM3(TO)4(GeO4)x(SiO4)3-x M = Cs+, Na+, K+, T=Nb5+, Ge4+, Ti4+) structures are excellent candidates for selectivity studies because of their ion-exchange properties tunable by alterations of synthetic procedures, and isomorphous framework substitution. The Nb-substitution in titanium sites reduces the framework charge, whereas Ge substitution decreases the unit cell size if in titanium sites and increases if it in silicon sites. The compounds were hydrothermally synthesized in Ti/Si, Ti/Nb/Si, Ti/Ge/Si forms and characterized by structural and ion-exchange studies. The 25% Nb substitution in titanosilicate sitinakite resulted in enhanced selectivity for cesium and additional bond formation of cesium within the channel. The selectivity for cesium in germanium substituted pharmacosiderite also was correlated with the coordination environment within the channel. In the advanced stages of this study semi-crystalline (sodium nonatitanate) and amorphous (monosodium titanate) materials also were considered because of their remarkable strontium selectivity. In situ X-ray diffraction techniques revealed that the sodium nonatitanate precedes the formation of the TS phase in hydrothermal synthesis. This knowledge allowed us to design and synthesize material for combined cesium and strontium removal.
106

The decision mapping system : promoting transparency of long-term environmental decisions at Hanford /

Drew, Christina H. January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 261-272).
107

Social Assessment of Siting a Low-Level Radioactive Waste Storage Facility in Michigan

Stoffle, Richard W., Traugott, Michael J., Stone, John V., McIntyre, Paula Drury, Davidson, Carla C., Jensen, Florence V., Coover, Gail E. January 1990 (has links)
This report presents findings from a social assessment of siting a low­ level radioactive waste storage facility in Michigan. The research focused specifically on how people perceive themselves to be affected by the proposed facility and the degree of community support for and opposition to the facility. Social assessment research in the LLRW project consisted of a telephone survey of Michigan residents and an in-depth ethnographic survey of residents in the tri-state area of Michigan, Indiana and Ohio. Findings from these studies can aid in the development and implementation of a social monitoring program and in the design of community-based measures to mitigate unwanted social impacts.
108

Public policy and nuclear waste: the siting of burial facilities

Laney, Nancy Kay January 1979 (has links)
No description available.
109

A laboratory facility for testing the performance of borehole plugs in rocks subjected to polyaxial loading

Cobb, Steven Lloyd January 1981 (has links)
No description available.
110

Wanapum Overview and Perspectives Developed During Tribal Narrative Workshop

The Wanapum Tribe, Stoffle, Richard, Arnold, Richard 06 1900 (has links)
The Greater than Class C (GTCC) Environmental Impact Statement (EIS) evaluated the potential impacts from the construction and operation of a new facility or facilities, or use of an existing facility, employing various disposal methods (geologic repository, intermediate depth borehole, enhanced near surface trench, and above grade vault) at six federal sites and generic commercial locations. For three of the locations being considered as possible locations, consulting tribes were brought in to comment on their perceptions on how GTCC low level radioactive waste would affect Native American resources (land, water, air, plants, animals, archaeology, etc.) short and long term. The consulting tribes produced essays that were incorporated into the EIS and these essays are in turn included in this collection. This essay was produced by the Wanapum Tribe for the Hanford Site.

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