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Aqueous Uranium Slurry Studies

Description: A summary of the laboratory development program on aqueous uranium slurry fuels for the Homogenous Reactor Project during the period April 1951 through March 1953 is presented. These investigations were devoted primarily to a study of the uranium oxides in aqueous suspensions. It was concluded that U(VI) was most likely to be the stable valence state in such slurry fuels and it was shown that β-UO3·H2O platelet crystals were the stable modification at 250°C. Very pure slurries of β-UO3·H2O platelets, uranium concentration of 250g/liter and average particle size of about 10 μ, had favorable settling rates and could be easily redispersed. Their viscosity and corrosion rate in stainless steel were comparable with those in water. Exposure of these slurries to pile radiation disclosed that radiolytic hydrogen and oxygen gas pressure comparable in magnitude to those of uncatalyzed uranyl sulfate solutions could be expected. Fission products in the irradiated slurries were predominantly associated with the solids. Radiation also tended to promote caking of these solids on the walls of the radiation bombs. Uranyl phosphate and the magnesium uranates were briefly investigated as alternate system but were not found satisfactory. The program was discontinued before the feasibility of uranium slurries for reactor fuels could be definitely established.
Date: October 20, 1955
Creator: Blomeke, J. O.; Bamberg, J. L.; Blomeke, J. O.; Bruce, F. R.; Fulmer, J. M.; McBride, J. P. et al.
Partner: UNT Libraries Government Documents Department
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A Fused Salt—Fluoride Volatility Process for Recovery and Decontamination of Uranium

Description: A preliminary chemical flowsheet is presented of a fluoride volatility process for recovering and decontaminating uranium from heterogeneous reactor fuels after dissolution in a fused salt. In laboratory work, a gross β decontamination factor of > 10 4 was obtained in the fluorination of a UF4-NaF-ZrF4 melt by passing the product UF6 through NaF at 650°C. The solubility of UF6 in molten NaF-ZrF4 was shown in kinetic studies to cause a lag in the evolution of UF6 from the fluorinator. Corrosion of nickel in the fluorination step appeared to be 2-4 mils/hr during the time that uranium was present. The average corrosion rate over the process as a whole was less than O.4 mil/hr. Earlier studies were reported in ORNL-1709 and 1877.
Date: October 10, 1955
Creator: Cathers, G. I. & Bennett, M. R.
Partner: UNT Libraries Government Documents Department
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Dissolution of Metals in Fused Fluorides

Description: In scouting tests, a number of metals used in nuclear reactor fuel elements were dissolved by 44.5-48.5-7.0 mole % ZrF4-KF-NaF fused salt at 675°C through which HF was being passed. These included type 304 stainless steel at 4 mils/hr; type 347Nb stainless steel at 7 mils/hr; thorium at 14 mils/hr; nonirradiated uranium at 17 mils/hr; zirconium at 22-35 mils/hr; titanium at 31 mils/hr; and Zircaloy-2 at 22-46 mils/hr. Only small amounts of volatile fission products formed when irradiated uranium was dissolved. Variables that appear to affect the dissolution rate are the composition of the fused fluoride, the fused fluoride temperature, the HF flow rate, the metallurgical characteristics of the material being dissolved, and the presence of other metals. The low dissolution rate of 0.001 mil/hr observed for nickel suggests that it may be suitable as a material of construction for reaction vessels.
Date: October 12, 1953
Creator: Leuze, R. E.; Cathers, G. I. & Schilling, C. E.
Partner: UNT Libraries Government Documents Department
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Homogeneous Reactor Project Quarterly Progress Report

Description: Part I. Experimental Reactors: The design has been completed for all the major high-pressure and low-pressure components except the reactor pressure vessel. Contained in this report are the most recent revisions of the low-pressure-system flow sheet, a description of important details of the reactor cell, and the final design of the main heat exchangers, the inner dump tanks and separator. the recombiner and recombiner-condenser, and the outer dump tank and reflux condenser. Part II. Thorium Breeder Reactor: An analysis of the relative effects of major process variables on the economics and characteristics of two-region thorium breeder reactors is nearing completion, and the results to date are presented in this report. From these results most of the major reactor characteristics have been determined; they are reported with certain other engineering studies pertinent to the early phases of the program. Part III. Corrosion: One loop was removed from service and cross sectioned for inspection of the internal surfaces. This loop was of type 347 stainless steel pipe and had a cumulative operating time of more than 12,000 hr with uranyl sulfate solutions varying in concentration from 0.004 to 1.34 m. No excessive or localized corrosion attack was noted except in one highly turbulent area immediately downstream from the in-line corrosion sample holder.
Date: October 31, 1954
Creator: Swartout, J.A.; Winters, C.E.; Beall, S. E.; Moore, W. C.; Bohlmann, E. G.; Lane, J. A. et al.
Partner: UNT Libraries Government Documents Department
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The Combination of Hydrogen and Oxygen in Platinum Catalyzed Flow Reactions

Description: An extension of the concepts advanced by Langmuir regarding the nature of the platinum catalyzed oxidation of hydrogen and the application of the resulting theory to the experimental data observed by Ranschoff and Spiewak for an HRE type recombiner indicates that their data are corrected by the dimensionless equation (see report) equally well, with a mean deviation of 3.8 percent. This expression is recommended as a basis for the design of catalytic recombiners. The catalytic combinations is pictured as consisting of two surface chemical mechanisms, one of which is oxygen diffusion controlled, the other hydrogen diffusion regulated, the mechanism "change-over" occurring at that point in the recombiner where the components are arriving at the catalyst surface by diffusion in stoichiometric proportions. The catalyst volume requirements for three two portions of the bed are shown to be (see report). The hydrogen mole fraction at the mechanism "change-over" point is (see report). And the relationship between the two mass transfer coefficients is (see report). Methods for evaluating the necessary transport properties of the ternary system steam-hydrogen-oxygen for carrying out design calculations are summarized, and the new significant parameters are tabulated and plotted to facilitate these calculations. The question of non-uniform velocity profiles in packed bed flow systems, as it applied to the recombiner problem, is considered, and it is indicated that small scale test data may be used directly as a basis for designing larger units. Finally, some of the questionable aspects of the analysis of the problem are reviewed, and further experiments that should be performed to settle the doubtful point are suggested.
Date: October 26, 1954
Creator: Garber, Harold J. & Peebles, Fred N.
Partner: UNT Libraries Government Documents Department
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The Oak Ridge National Laboratory Research Reactor Safeguard Report

Description: This memorandum sets forth a recommended uniform basis for designing the ORN shield.This includes design values for power level and emergent radiation, standards values for various material properties, and basic radiation intensities.
Date: October 7, 1954
Creator: Binford, F.T.; Cole, T.E. & Gill, J.P.
Partner: UNT Libraries Government Documents Department
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The Oak Ridge National Laboratory Research Reactor Safeguard Report

Description: The proposed ORNL Research Reactor is designed to serve as a general purpose research tool delivering a maximum thermal flux of 8x10^13 n/cm2-sec at the initial power level of five megawatts. Operation at power levels up to ten megawatts is proposed for such items as sufficient cooling capacity is available to handle the increased heat load. The reactor will use MTR-type fuel elements and beryllium reflector pieces in a 7 x 9 grid with moderation and cooling provided by forced circulation of demineralized water. The reactor tanks are submerged in a barytes concrete pool, filled with water, which serves as a biological shield. Experimental facilities include two 18" diameter "Engineering Test Facilities" and six 6" diameter beam holes. In addition, access to the core is available through the water of the pool. The result on the surrounding population of release to the atmosphere of a large fraction of the radioactive material in the core has been computed by two methods. It is shown that under certain conditions off-area personnel could be subjected to greater than the maximum permissible exposure. An analysis of the maximum hazard caused by the release of the entire contents of the core to the local watershed indicates that the resulting incident could be quite serious, but with proper monitoring and supervision would probably not constitute a lethal hazard. The probability of the occurrence of a catastrophic release of activity of sufficient magnitude to cause widespread hazard to life is quite small and it is believed that the measures taken to lessen this probability are adequate. An Appendix, Volume II, contains supporting information for this report, and is also intended to serve as a reference for future use.
Date: October 7, 1954
Creator: Binford, F.T.; Cole, T.E. & Gill, J.P.
Partner: UNT Libraries Government Documents Department
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Re-entry Flight Demonstration Number One (RFD-1): Atmospheric Sciences Support

Description: Abstract: Data from the atmospheric sciences support systems for RFD-1 on May 22, 1963, at Bermuda Island, are presented. These data were taken for purposes of later analysis of the ballistic performance of the re-entry vehicle and of the heat transfer mechanisms within it, and for studies of the motion of ablated particles in the atmosphere.
Date: October 1964
Creator: Coonce, C. A.
Partner: UNT Libraries Government Documents Department
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Philosophy and Religious Studies Collection Evaluation Report

Description: This report summarizes an evaluation of the UNT Libraries' Philosophy and Religious Studies collection to determine if the collection is adequately serving patron needs. It was determined that the collection was currently meeting patrons' needs, and some recommendations for future collection maintenance were included.
Date: October 15, 2021
Creator: Harker, Karen
Partner: UNT Libraries
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Speech & Hearing Sciences Collection Evaluation

Description: This report summarizes an evaluation of the UNT Libraries' Speech and Hearing Sciences collection to determine if the collection is adequately serving patron needs. It was determined that the collection was currently meeting patrons' needs, and some recommendations for future collection maintenance were included.
Date: October 15, 2021
Creator: Harker, Karen
Partner: UNT Libraries
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Africana Studies Collection Evaluation Report

Description: This report summarizes an evaluation of the UNT Libraries' Africana Studies collection to determine if the collection is adequately serving patron needs. It was determined that the collection was currently meeting patrons' needs, and some recommendations for future collection maintenance were included.
Date: October 15, 2021
Creator: Harker, Karen
Partner: UNT Libraries
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LSR Responsibility Matrix

Description: Spreadsheet titled "LSR Responsibility Matrix" dated 10/10/2006. The spreadsheet outlines the responsibilities for each event and category of fundraising with due dates and the notes for the committee who is in charge based on the key of P, S, and A.
Date: October 10, 2006
Partner: UNT Libraries Special Collections
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A Proposal for a National Center for Art Museum/School Collaborations

Description: A proposal for the National Center for Art Museum/School Collaborations, submitted to the Getty Center for Education in the Arts, by the North Texas Institute for Educators on the Visual Arts.
Date: October 1, 1994
Creator: North Texas Institute for Educators on the VIsual Arts
Partner: UNT Libraries Special Collections
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Interim Report and Third Quarter Recommendations, October 2020

Description: A report containing the National Security Commission on Artificial Intelligence (NSCAI)'s third quarterly memo and second interim report with 66 recommendations in key areas. They are organized under five tabs: strengthening the triangular alliance for AI research, applying AI for national security missions, training and recruiting AI talent, protecting and building upon U.S. technology advances, and marshaling global AI cooperation & ethics.
Date: October 2020
Creator: National Security Commission on Artificial Intelligence (U.S.)
Partner: UNT Libraries Government Documents Department
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Boiling Heat Transfer of Liquid Metals: a Literature Search

Description: This partially annotated bibliography contains references on boiling heat transfer of liquid metals. Emphasis is place on boiling heat transfer of liquid sodium, liquid potassium, and liquid rubidium. The period covered is 1950 to date. References are arranged alphabetically by title. Sources used in compiling this bibliography are: Abstracts of Classified Reports, Nuclear Science Abstracts.
Date: October 3, 1960
Creator: Cernak, Elizabeth A.
Partner: UNT Libraries Government Documents Department
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Evaluation of Commercial Ceramic Coating for Short Time Protection of Columbium 1% Zirconium

Description: Abstract. Fourteen commercial enamel frits from five different manufacturers were tested to determine their abilities to protect Nb-1% Zr during the forging cycle in the temperature range of 1800 to 2300 deg F. One frit was found to afford good coverage and protection at 2200 deg F at times up to 5 hours of exposure. Adherence was excellent during upset forging of a coated Nb--1% Zr sample heated 45 minutes at 2200 deg F. Another frit afforded good protection and coverage at 1700 deg F. (auth)
Date: October 10, 1960
Creator: McGrath, D. W.
Partner: UNT Libraries Government Documents Department
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A Study of Thorium Peroxide Sulfate

Description: Abstract. Thorium peroxide was precipitated from thorium nitrate solutions containing varying amounts of sulfate ion and of hydrogen ion. The washed solids were analyzed both wet and dry. Analyses were made for thorium, peroxide oxygen, sulfate, nitrate, and water contents. X-ray powder photographs of the dried samples by W.H. Zachariasen showed the presence of only two phases. When precipitated from high sulfuric acid, the solid phase was isomorphous with Th(OO)SO4.3H20. More weakly acid solutions whose sulfate content was varied over wide limits [SO4--/Th(IV) (in solution before precipitation) = 0.005 to 67.0] yielded a solid, isomorphous with thorium peroxide nitrate and containing 3.0 to 3.8 peroxide oxygen atoms for each thorium atom. The sulfate content of this latter phase varied continuously between the limits SO4--/Th(IV) = 0.34 to 0.01 with nitrate ion present when the sulfate content was very low. This continuous variation in composition is in agreement with the previously proposed structure of this phase.
Date: October 1, 1945
Creator: Hamaker, John W.
Partner: UNT Libraries Government Documents Department
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Radiocarbon from Pile Graphite; Chemical Methods for its Concentration

Description: Abstract. Samples of pile graphite, irradiated in a test-hole at Hanford for 15 months, have been assayed for radioactive C14, yielding 0.38 ± 0.04 microcuries per gram. At this level of activity, the pile graphite contains very valuable amounts of C14. The relation between the above assay and the probable average assay of pile graphite is discussed, and it is concluded that the latter is almost certainly above 0.3 uc/ gram. Controlled oxidation of this graphite, either with oxygen at ~ 750°C, or with chromic acid "cleaning solution" at room temperature, yields early fractions which are highly enriched in C14. Concentrations of 5-fold with oxygen, and 50-fold with CRO{sub3}, have been observed. The relation between the observed enrichment and the Wigner effect is discussed, and a mechanism accounting for the observations put forward. According to this, about 25% of the stable carbon atoms in the lattice have been displaced by Wigner effect, a large fraction of which have healed the migrating to crystal edges. All the C14 atoms have been displaced, and the same fraction of these migrate to the edges. The enrichment then results from surface oxidation, in the oxygen case. Predictions are made on the basis of this hypothesis. A technique of counting radioactive CO2 in the gas phase is described
Date: October 10, 1946
Creator: Arnold, James R. & Libby, Willard F.
Partner: UNT Libraries Government Documents Department
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Recovery of D2O and UO2F2 by Distillation

Description: Technical report describing the purification and separation by distillation of UO2F2 from D2O. In the experiment which is discussed 2,129.6 lbs of UO2F2 were dissolved in 6,605 lbs of D2O. The average isotopic purity of the D2O decreased during the distillation from 99.77% to 99.73%. The dissolved impurities were less than those present originally in the heavy water.
Date: October 10, 1945
Creator: Fischer, R. & Wattenberg, Albert, 1917-
Partner: UNT Libraries Government Documents Department
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Analysis of Uranium-Manganese Alloys

Description: Introduction. the conventional procedures of analysis for uranium and manganese can be employed in the analysis of alloys of these metals. The alloys are reacted with perchloric acid and hydrogen peroxide, fumed to remove any chloride ions, diluted to volume and aliquots analyzed by redoximetry.
Date: October 5, 1945
Creator: Ayers, A. S.
Partner: UNT Libraries Government Documents Department
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Precipitation of Thorium Oxalate from Nitric Acid Solutions

Description: Introduction. It has been known for a long time that thorium is precipitated by oxalic acid in acid solutions, but a survey of the literature showed no study of the limits of the acidity and oxalic acid excess which yield quantitative results. V. I. Spitzin reports on the solubility of thorium oxalate in varying concentrations of several acids, but the effect of an excess oxalic acid is not included. Since solutions are sometimes presented for analysis that contain more than the recommended two per cent mineral acid, it would be advantageous to be able to quantitatively remove the thorium without otherwise altering the solutions. This was especially of interest in solutions containing bismuth, since it was hoped that some amounts of thorium could be precipitated in nitric acid solutions containing large quantities of bismuth. In removing the bismuth, first by a bismuth oxychloride precipitation, thee is every opportunity for carrying of the thorium.
Date: October 5, 1945
Creator: Ayers, A. S.
Partner: UNT Libraries Government Documents Department
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The Wigner Effect in Graphite, Relationship Between Advantage Factor and Location of Samples in an Operating Pile

Description: Technical report. The extent of the Wigner effect in graphite at any point in a pile is sensitive to the local structural situation. It is greater near a slug. These control experiments give information on changes in graphite to be expected in selected places in the pile.
Date: October 20, 1944
Creator: Novick, A.; Neubert, T. J. & Burton, Milton, 1902-
Partner: UNT Libraries Government Documents Department
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