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Description: A survey of the pertinent literature was made to ascertain the status of data on U/sup 233/ fission-product yields. The various experimental determinations were evaluated, and the most recent mass-spectrometric results were used as a basis for deriving a set of preferred yields. These yields were compared with values reported in two other recent compilations, and for yields >1%, the three setrs agreed with each other to an average precision of <5%. It was concluded that recent measurements have somewhar improved the reliability of U/sup 233/ fission yield data, but some recommendations for additional experimental work were made (auth)
Date: July 13, 1962
Creator: Ferguson, R.L. & O'Kelley, G.D.
Partner: UNT Libraries Government Documents Department


Description: The status of thorium and uraniumn-233 technology for power reactor applications is reviewed. In the areas of fuel cycle, reactor design snd reactor operational problems, information was s developed on current status of techology, current and planned research and developrent programs, need for additional resesrch and developmet, and time schedule of required kilograms of U-23 over the next five years to carry out the research and development now being planned, and the further work believed desirable in the longer term. (auth)
Date: December 11, 1957
Creator: Mash, D.R. & Ottenberg, A.
Partner: UNT Libraries Government Documents Department

Technical Competencies for the Safe Interim Storage and Management of 233U at U.S. Department of Energy Facilities

Description: Uranium-233 (with concomitant {sup 232}U) is a man-made fissile isotope of uranium with unique nuclear characteristics which require high-integrity alpha containment biological shielding, and remote handling. The special handling considerations and the fact that much of the {sup 233}U processing and large-scale handling was performed over a decade ago underscore the importance of identifying the people within the DOE complex who are currently working with or have worked with {sup 233}U. The availability of these key personnel is important in ensuring safe interim storage, management and ultimate disposition of {sup 233}U at DOE facilities. Significant programs are ongoing at several DOE sites with actinides. The properties of these actinide materials require many of the same types of facilities and handling expertise as does {sup 233}U.
Date: February 17, 1999
Creator: Campbell, D. O.; Krichinsky, A. M.; Laughlin, S. S.; Van Essen, D. C. & Yong, L. K.
Partner: UNT Libraries Government Documents Department

Development of the accelerator-driven energy production concept

Description: This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Accelerator Driven Transmutation Technology (ADTT) offers a means of generating nuclear energy in a clean, safe way that can be attractive to the general public. However, there are issues associated with the energy story (both at the system level and technical detail) that have to be seriously addressed before the scientific community, the public, and potential industrial sponsors can be compellingly convinced of its cost/benefit.
Date: October 1, 1996
Creator: Venneri, F.; Beard, C. & Bowman, C.
Partner: UNT Libraries Government Documents Department

Disposition of uranium-233

Description: The US is developing a strategy for the disposition of surplus weapons-usable uranium-233 ({sup 233}U). The strategy (1) identifies the requirements for the disposition of surplus {sup 233}U; (2) identifies potential disposition options, including key issues to be resolved with each option; and (3) defines a road map that identifies future key decisions and actions. The disposition of weapons-usable fissile materials is part of a US international arms-control program for reduction of the number of nuclear weapons and the quantities of nuclear-weapons-usable materials worldwide. The disposition options ultimately lead to waste forms requiring some type of geological disposal. Major options are described herein.
Date: October 16, 1997
Creator: Tousley, D.R.; Forsberg, C.W. & Krichinsky, A.M.
Partner: UNT Libraries Government Documents Department

Subcritical Limits for {sup 233}U Systems

Description: As a contribution to the required quinquennial review of American National Standard for Nuclear Criticality Safety in Operations with Fissionable Materials Outside Reactors (ANSI N16.1-1975/ANS-8.1), limits for homogeneous 233U systems have been recalculated to confirm their sub-criticality or, where there were doubts, to propose more restrictive values. In addition, other limits were calculated to be proposed for inclusion, namely, limits for aqueous solutions of UO2(NO3)2 and limits for uranium oxides. The same three methods of calculation were used as in similar work done recently for plutonium and 235U systems. The validity of each was established by correlation with the results of pertinent critical experiments. This report discusses this study.
Date: October 21, 1981
Creator: Clark, H.K.
Partner: UNT Libraries Government Documents Department


Description: The fuel value of U/sup 233/ was calculated for five thermal reactors (Dresden. Yankee, Carolinas-Vlrginia, Hallam, GCR-II). Relative to a U/sup 235/ value of per gram, pure U/sup 233/ had a value that varied from .2 to .2 per gram. U/sup 233/ contained in once- and twice-recycle uranium from an initial U/sup 233/-Th cycle had a value slightly in excess of the value of pure U/ sup 233.. The value of U/sup 233/ in recycle uranium from an initial U/sup 235/- Th cycle was less than that for pure U/sup 233/ and decreased with each succeeding cycle. (auth)
Date: April 11, 1960
Creator: Jaye, S; Bennett, L L & Lietzke, M P
Partner: UNT Libraries Government Documents Department


Description: Uranium-233 (t{sub 1/2} {approx} 1.59E5 years) is an artificial, fissile isotope of uranium that has significant importance in nuclear forensics. The isotope provides a unique signature in determining the origin and provenance of uranium-bearing materials and is valuable as a mass spectrometric tracer. Alpha spectrometry was employed in the critical evaluation of a {sup 233}U standard reference material (SRM-995) as a dual tracer system based on the in-growth of {sup 229}Th (t{sub 1/2} {approx} 7.34E3 years) for {approx}35 years following radiochemical purification. Preliminary investigations focused on the isotopic analysis of standards and unmodified fractions of SRM-995; all samples were separated and purified using a multi-column anion-exchange scheme. The {sup 229}Th/{sup 233}U atom ratio for SRM-995 was found to be 1.598E-4 ({+-} 4.50%) using recovery-corrected radiochemical methods. Using the Bateman equations and relevant half-lives, this ratio reflects a material that was purified {approx} 36.8 years prior to this analysis. The calculated age is discussed in contrast with both the date of certification and the recorded date of last purification.
Date: December 6, 2011
Creator: Beals, D.
Partner: UNT Libraries Government Documents Department


Description: A system for concentrating uranyl nitrate solutions was designed and installed in the Thorex Pilot Plant. A total of 16,060 g of uranium was concentrated in the system in 68 batch runs. A total of 14,400 g total uranium (14.180 g U/sup 233/) was recovered as product suitable for shipment. Uranium loss to the evaporator condensate was 0.03% of ihe total uranium processed. The material balance across the system was 98.4%. The average concentration of uranium in the evaporator feed solution was 29 g/liter; the average concentration in the evaporated solution was 298 g U/liter and in the product solution was 199 g/liter. Radiation readings of bottles containing product solutions were taken with a hard-shell cutie pie immediately after each run, and these readings ranged from 35 to 1100 mr/hr. The radiation levels of the bottles of product solution shipped averaged 78 mr/hr. Bottles of product solution reading in excess of 300 mr/hr, maximum allowable for shipment. were reprocessed in the second-cycle solvent extraction system (Thorex) and reconcentrated. The products from seven runs had radiation levels in excess of 300 mr/hr at the time of concentration, or the activities had grown to that level by the time of shipment. The procedures used in the operation of the above system are described in detail. (auth)
Date: January 28, 1957
Creator: Albrecht, W.L.
Partner: UNT Libraries Government Documents Department


Description: The accuracy with which the breeding ratio of HRE-3 could be determined after a period of reactor operation was investigated. Inaccuracies in measurement of the core U/sup 233/ inventory and blanket U/sup 233/ and Pa/sup 233/ inventories appear to be the major sources of error. Appreciable errors could result from attempting to determine these inventories by sampling the reactor contents. For example, if generalized attack on stainless steel is at a rate of 1.0 mpy and if the associated film of corrosion products is 1% uranium, failure to account for this fuel in evaluation of the core inventory would cause an error of about 5% in the breeding ratio. (auth)
Date: May 27, 1958
Creator: Rosenthal, M.W.
Partner: UNT Libraries Government Documents Department


Description: The design and economics of the Aqueous Homogeneous Reactor as basically under development at the Oak Ridge National Laboratory are presented. The reactor system utilizes thorium-U-233 fuel. Conditions accompanying reactor systems generating up to l080 mw of net electrical energy are covered. The study indicates that a generating station, with a net thermal efficiency of 28.l%, might be constructed for approximately 0/kw and 0/kw at the l80 mw and l080 mw electrical levels, respectively. These values result in capital expenses of approximately 4.72 and 2.86 milis/kwh. A major part of fuel cost is the expense of chemical processing. It is therefore advantageous 10 schedule fuel through a relatively large processing system since fixed charges are insensitive to chemical plant size. By handling fuel through a plant large enough for processing 200 kg of thorium per day, total fuel costa of about 1 mill/kwh result. This cost for fuel processing appears applicable to generating stations up to abeut 540 mw in size, decreasing to about 0.6 mills/kwh at the l080 mw level. Operating and maintenance expense, including heavy water cost on a lease basis, varies between l.34 and 0.89 mills/kwh for l80 and l080 megawatts respectively. If the purchase of heavy water is required, 0.3 to 0.4 mills/kwh must be added. It is concluded that the Aqueous Homogeneous Reactor may produce electrical power competitive with conventional generating systems when the remaining technical problems are solved. It is felt ihat the research and development now programed by the Oak Ridge National Laboratory will solve these problems and affect costs favorably. (auth)
Date: February 1, 1955
Creator: Carson, H.G. & Landrum, L.H. eds.
Partner: UNT Libraries Government Documents Department