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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.
21

Recovery of neptunium in the modified purex process

Tajik, Saeed. January 1979 (has links)
Thesis: M.S., Massachusetts Institute of Technology, Department of Chemical Engineering, 1979 / Includes bibliographical references (leaves 207-212). / by Saeed Tajik. / M.S. / M.S. Massachusetts Institute of Technology, Department of Chemical Engineering
22

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.
23

A dynamic multi-criteria analysis of spent-nuclear-fuel alternatives

Langham, Robert William II 30 March 2010 (has links)
A generalized multiple-objective research and development (R & D) capital budgeting model incorporating production-allocation decisions is developed for the analysis of the spent-nuclear-fuel management problem. The generalized model is decomposed into two subproblems. First is a multiple-objective R&D capital budgeting problem and second is a multiple-objective fuel allocation problem. Goal programming is selected as an appropriate modeling technique for both generic models. The spent-nuclear-fuel-allocation problem is further decomposed into a dynamic program with a goal program at each stage. The objectives are to allocate R&D funds to process or technology development and to allocate spent fuel to certain alternatives so as to minimize the weighted and prioritized vector cost. With regard to the objectives of non-proliferation and non-diversion, occupational and population exposure, uranium resource conservation, and fuel cycle economics. the major conclusion is to use the spent fuel for further energy production, preferably via a combination of extended burnup and recycle alternatives. / Ph. D.
24

Uranium dioxide and urania-thoria fuel cores for the UTR-10 reactor

Atwell, Robert L. 08 September 2012 (has links)
Theoretial calculations of critical mass, temperature coefficient, and transient behavior have been made for proposed uranium dioxide and urania-thoria fuel cores for the Virginia Polytechnic Institute UTR-10 Reactor. / Master of Science
25

An optimal withdrawal policy for spent nuclear fuel from on-site storage

Swindle, David Wesley 30 October 2008 (has links)
The need to extend light water reactor spent-fuel on-site storage requirements and the future need to relieve resulting stockpiles necessitates the determination of optimal spent-fuel-withdrawal patterns under various end-use scenarios. End-use scenarios include no-economic- return throwaway and uranium recycle with and without plutonium recycle. Results from developing, analyzing, and solving a spent-fuel-withdrawal model are used to recommend specific strategies. The spent-fuel-withdrawal problem involves the interaction of spent-fuel generation, time and capacity-dependent reprocessing demand, and expected spent-fuel value. Spent-fuel characteristics based upon burnup history and initial composition, are considered along with uranium, separative work, and storage cost projections to realize profitable spent-fuel disposition. Application of the spent-fuel-withdrawal model is done on a per-reactor basis. Assumptions inherent in the application of the model developed include, 1) unconstrained on-site storage capacity, 2) realizable uranium and plutonium values, and 3) capacity constrained reprocessing demand. Examining supply, demand, and characteristics of spent-fuel during a twenty-year horizon, the model application is developed through, 1) a dynamic programming approach, 2) a Hitchcock problem to be solved similarly to a minimum-cost-flow problem, and 3) a linear program definable as a Transportation problem. In the model analyses, the dynamic programming formulation proved to be computationally infeasible. The analyses of the Hitchcock and linear program problem is done by the use of the Out-Of-Kilter Algorithm and the proprietary mathematical MPS-III system, respectfully. Specific results indicate that the economically optimal withdrawal pattern is: 1) for uranium and plutonium recycle, a Last-In-First-Out pattern, and 2) for uranium recycle only, no discernible pattern. / Master of Science
26

Aqueous complexation of citric acid and DTPA with selected trivalent and tetravalent f-elements

Brown, M. Alex 03 July 2013 (has links)
Carboxylic acids have played an important role in the field of actinide (An) and lanthanide (Ln) separations and the reprocessing of irradiated nuclear fuel. Recent bench-scale experiments have demonstrated that 3-carboxy-3-hydroxypentanedioic acid (citric acid) is a promising aqueous complexant that can effectively aid in the separation of transition metals from f-element mixtures. Furthermore, citric acid was found to be a suitable buffer for the nitrogen donating ligand diethylenetriamine-N,N,N',N'',N''-pentaacetic acid (DTPA) which has a higher complexation affinity for An over Ln. The complexation of Ln and An with anions of citric acid and DTPA have been previously studied with conflicting results regarding the coordination of metal ions between carboxylic groups, the feasibility of protonated metal complexes, and the formation constants themselves. Using potentiometry, spectrophotometry,microcalorimetry, and specific ion interaction modeling, we investigated metal complexes of citric acid and DTPA with selected trivalent and tetravalent Ln and An ions. The complexes were investigated with respects to stability constants, thermodynamics of complexation, oxidation states, the concentration of electrolyte, ligand size, thermodynamics of complexation, oxidation states, the concentration of electrolyte, ligand size, and metal ionic radius. / Graduation date: 2013 / Access restricted to the OSU Community at author's request from Jan. 3, 2013 - July 3, 2013
27

Fuel depletion analyses at the Missouri University Research Reactor

Ion, Robert Aurelian, January 2006 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (March 2, 2007) Vita. Includes bibliographical references.
28

Subcritical transmutation of spent nuclear fuel

Sommer, Christopher Michael 07 July 2011 (has links)
A series of fuel cycle simulations were performed using CEA's reactor physics code ERANOS 2.0 to analyze the transmutation performance of the Subcritical Advanced Burner Reactor (SABR). SABR is a fusion-fission hybrid reactor that combines the leading sodium cooled fast reactor technology with the leading tokamak plasma technology based on ITER physics. Two general fuel cycles were considered for the SABR system. The first fuel cycle is one in which all of the transuranics from light water reactors are burned in SABR. The second fuel cycle is a minor actinide burning fuel cycle in which all of the minor actinides and some of the plutonium produced in light water reactors are burned in SABR, with the excess plutonium being set aside for starting up fast reactors in the future. The minor actinide burning fuel cycle is being considered in European Scenario Studies. The fuel cycles were evaluated on the basis of TRU/MA transmutation rate, power profile, accumulated radiation damage, and decay heat to the repository. Each of the fuel cycles are compared against each other, and the minor actinide burning fuel cycles are compared against the EFIT transmutation system, and a low conversion ratio fast reactor.
29

Development and implementation of a response-function concept for spent nuclear fuel cask analysis

Foster, Jack Warren 12 1900 (has links)
No description available.
30

Multidisciplinary design approach and safety analysis of ADSR cooled by buoyancy driven flows

Ceballos Castillo, Carlos Alberto, January 2007 (has links)
Thesis (doctoral)--Delft University of Technology, 2007. / "Proefschrift ter verkrijging van de graad van doctor aan de Technische Universiteit Delft." Includes bibliographical references (p. 120-128) and index.

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