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Enthalpies and Heat Capacities of Solid and Molten Fluoride Mixtures
The enthalpies and heat capacities of seventeen fluoride mixtures in the liquid state have been determined using Bunsen Ice Calorimeters and copper block calorimeters. The fluoride mixtures were composed of the fluorides of two or more of the following metals: lithium, sodium, potassium, beryllium, zirconium, and uranium. The enthalpies and heat capacities of most of these mixtures were studied in the solid state also. Estimates of the heat of fusion have been made. General empirical equations have been developed which represent the enthalpies and heat capacities of the fluoride mixtures in the liquid and in the solid state.
Date:
January 11, 1956
Creator:
Powers, W. D. & Blalock, G. C.
System:
The UNT Digital Library
The Influence of End Mirrors, High Density and Long Tube Length on Radial Diffusion
Diffusion in an arc plasma across a magnetic field is investigated. The geometry is similar to that reported in ORNL-1890 but with the addition of magnetic mirrors on the ends of the arc chamber. It is shown that mirrors do not eliminate the "short circuit" effect. Comparison of the e-folding length, rₒ, of the radial ion density with and without mirrors, affords a direct measurement of ℓ/λ where ℓ is the arc length and λ the mean-free-path. In addition rₒ is independent of gas pressure with mirrors and varies as √p without mirrors. The condition for the elimination of the "short circuit" effect is discussed, as well as the case in which the "short circuit" is still present but the ions diffuse (rather than stream) to the end walls. In this case rₒ is directly proportional to the gas pressure. These effects are compared to some experimental results of Neidigh
Date:
September 22, 1955
Creator:
Simon, Albert
System:
The UNT Digital Library
Analytical Chemistry Division Semiannual Progress Report For Period Ending October 20, 1955
The development of ionic methods for the determination of corrosive products in the highly radioactive Homogeneous Reactor (HR) fuels has been of major interest in the work of the Ionic Analyses Laboratory. Methods for the spectrophotometric determination of aluminum and for the polarographic determination of iron in HR fuels have been developed. The polarographic determination of molybdenum in uranyl sulfate solutions was studied. A polarographic method for the determination of zinc was developed. A fluorometric method for the determination of microgram amounts of fluoride was studied. Three organic reagents were investigated as precipitants for microgram quantities of zirconium in HR fuel. The automatic photometric titration technique was applied to the determination of thorium and of sulfate. A method was developed for the ion-exchange separation and potentiometric titration of cobalt. The ultraviolet absorption spectra of technetium and rhenium were studied.
Date:
December 27, 1955
Creator:
Kelley, M. T.; Susana, C. D. & Rooen, H. P.
System:
The UNT Digital Library
Relative Biological Hazards of Radiations Expected in Homogeneous Reactors TBR and HPR
An evaluation of the relative health hazards of radioisotopes produced in nuclear reactors is reported. The most important hazards were indicated to be I131, the Sr90 - Y90 chain, the Ce144 -Pr144 chain, Sr 89, the Ba140-La40 chain, Y91, the Zr95-Nb95 chain, Pr143, La140 , and Pa233. The most critical body organs affected by air-borne contamination are the thyroid gland, the bone marrow, the lungs, and the gastrointestinal tract. Where possible, continuous daily removal of gaseous and solid fission products from the reactor environment can be shown to permit very significant reductions in the total hazards. Homogeneous reactors, such as the Thermal Breeder Reactor and the Homogeneous Plutonium Producer Reactor, specifically studied in this report, are designed with daily removal cycles and may be considered potentially safer than heterogeneous reactors.
Date:
December 2, 1955
Creator:
Arnold, E. D. & Gresky, A. T.
System:
The UNT Digital Library
Determination of Trivalent Uranium with Methylene Blue
A direct titrimetric method for the determination of trivalent uranium in uranium trifluoride and mixtures of fused fluoride salts was developed. The method is based on the stoichiometric oxidation of trivalent uranium to the tetravalent oxidation state with an acidic solution of methylene blue. The sample containing trivalent uranium is dissolved at room temperature in an excess of standard methylene blue solution in a carbon dioxide atmosphere; the excess oxidant is variation of the method is 1.5 per cent for 5 mg quantities of trivalent uranium. The method was applied to various mixtures of fluoride salts containing both trivalent and tetravalent uranium.
Date:
November 22, 1955
Creator:
Ross, W. J.; Meyer, A. S.; White, J. C.; Kelley, N. T. & Susano, C. D.
System:
The UNT Digital Library
Laboratory Development of the Thorex Process
Changes made in the Thorex process flowsheet were a decrease in the extraction column acidity to decrease thorium losses and the addition of a second thorium solvent-extraction cycle to provide the increased decontamination required when thorium irradiated to 2000-4000 g of U233 per ton is processed. Bonded slugs could not be dissolved by the Thorex flowsheet procedure. Various laboratory scale studies on feed preparation, first-cycle variables, and radiation damage to the solvent are reported.
Date:
June 12, 1956
Creator:
Wischow, R. P. & Mansfield, R. G.
System:
The UNT Digital Library
Chemical Separation of Isotopes Section Semiannual Progress Report for Period Ending June 30, 1955
The countercurrent gas-liquid system BF3(g)—anisole·BF3(l) for the concentration of boron isotopes has been studied. The single-storage separation factor varies from 1.039 at 0°C to 1.029 at 30°C. Rate of exchange is rapid, and, with efficient contacting equipment, complete exchange may be obtained in less than 15 sec. A total separation of 1.525 has been realized in laboratory equipment. The critical-product reflux reaction is quite efficient. Only about 55 moles of BF3 remain in each million moles of effluent solvent under laboratory conditions. The vapor pressure of BF3 over the complex rises sharply as the temperature is increased. At 0°C the pressure is 150 mm Hg, and at 40°C the pressure has risen to 1800 mm Hg. From vapor-pressure measurements, an approximate upper limit of ΔH= -12kcal per mole of complex was calculated for the reaction [equation not transcribed]. Qualitative tests indicate good resistance of anisole to decomposition by BF3 under plant conditions. The uncatalyzed exchange of boron between BF3 and BCl3 was found to be too slow to be exploited in a countercurrent system. The single-stage, equilibrium separation factor for the Nitrox system is a function of acid concentration. At 26°C the factor ranges from 1.064 with 1 M acid …
Date:
February 23, 1956
Creator:
Clewett, G. H. & Drury, J. S.
System:
The UNT Digital Library
Aircraft Nuclear Propulsion Project Quarterly Progress Report for Period Ending December 10, 1955
This quarterly progress report of the Aircraft Nuclear Propulsion Project at ORNL records the technical progress of the research on circulating-fuel reactors and other ANP research at the Laboratory under its Contract W-7405-eng-26. The report is divided into three major parts: I. Reactor Theory, Component Development, and Construction, II. Materials Research, and III. Shielding Research. The ANP Project is comprised of about 530 technical and scientific personnel engaged in many phases of research directed forward the achievement of nuclear propulsion of aircraft. A considerable portion of this research is performed in support of the work of other organizations participating in the national ANP effort. However, the bulk of the ANP research at ORNL is directed toward the development of a circulating-fuel type of reactor. The design, construction, and operation of the Aircraft Reactor Test (ART), with the cooperation of the Pratt & Whitney Aircraft Division, are the specific objectives of the project. The ART is to be a power plant system that will include a 60-Mv circulating-fuel reflector-moderated reactor and adequate means for heat disposal. Operation of the system will be for the purpose of determining the feasibility, and the problems associated with the design, construction, and operation, of a …
Date:
March 12, 1956
Creator:
Jordan, W. H.; Cremer, S. J.; Miller, A. J. & Savelainen, A. W.
System:
The UNT Digital Library
ORNL Mortal Recovery Plant: Processing of ORNL Graphite Reactor Fuel Elements During the Period July and August, 1955
From July 7 to August 31, 1955, 20 tons of uranium and 1,200 g of plutonium were recovered in 47 days of plant operation at an average rate of 833 lb/day of uranium and at a cost of $2.60/lb of uranium. Uranium and plutonium recoveries were, respectively, 99.9 and 95.5 per cent.
Date:
November 11, 1955
Creator:
Brooksbank, R. E.; Chandler, J. M. & Hylton, C. D.
System:
The UNT Digital Library
Preliminary Results of APPR Critical Experiments, Part I.
This memorandum is the first in a series reporting progress in the program of critical experiments in the ORNLArmy Package Power Reactor Project. The critical assembly, designated as CA-25, is analogous to the APPR design core and consists of 45 fuel boxes, in a 7 x 7 array with the corners removed, contaIned in a large water tank. Two sides of each box are slotted for the insertion and positioning of any desired loading of eighteen plates of fuel, structural material, and poison. The array is submerged in water to provide a moderated and reflector. Enriched uranium metal, in two-mil-thick foils 2.5 x 22 in, is encased in type 304 stainless steel sheets, 2.7 x 23 x 0.0105 in., to form fuel plates. Stainless steel plates, 2.7 x 23 x 0.025 in. are used to simulate additional steel in the APPR core. It is, therefore, possible to maintain an essentially constant metal to water ration in the assembly when the fuel content is varied. The fuel is distributed as uniformly as possible in all boxes and a symmetrical distribution of materials is maintained in the core at all times. Fuel plates containing half-width (1.25 in) uranium foils are provided for …
Date:
November 25, 1955
Creator:
Williams, D. V. P.
System:
The UNT Digital Library
Development of a Cubic Oxide Protective Film on Zirconium
Observations of the effects of neutron damage to zirconium oxides led to the conclusion that the cubic form of ZrO2 is more stable to such damage than the monoclinic form. It has been reported that zirconium corrodes more rapidly in certain liquids when exposure is made under radiation (neutrons and fission products). It is well known that on heating monoclinic ZrO2 a transformation, monoclinic to tetragonal (very similar to cubic), occurs at about 1500°C. The transformation involves sufficient atomic rearrangement that pieces of ZrO2 normally crack and crumble. It is suggested that the effects of neutrons on monoclinic ZrO2 may be similar so that a protective oxide film on the metal would be destroyed soon after its formation. It might be possible, therefore, that the protective oxide film on zirconium metal which is normally monoclinic might be less resistant to corrosion under radiation damage than a similar film which was cubic.
Date:
February 21, 1956
Creator:
Johnson, J. R.
System:
The UNT Digital Library
Bibliography of ORNL-BSF Reports Pertinent to Swimming Pool Type Reactor Design (Revised)
Much of the shielding work carried out with the Bulk Shielding Reactor (BSR) has yielded data of particular interest for the design of swimming pool type reactors, However, it is often difficult for a reactor designer to locate such data since it may be recorded in a report primarily concerned with shielding problems. Therefore, this memorandum presents a bibliography of reports from the Bulk Shielding Facility arranged according to the application of data to the various aspects of reactor design.
Date:
April 13, 1956
Creator:
Maienschein, F. C. & Johnson, E. B.
System:
The UNT Digital Library
Fission Product Activities in Irradiated Natural Uranium, Enriched Uranium, and Thorium
Calculated data and graphs describing the effects of batch thermal-neutron irradiations on the buildup of fission products in natural uranium, enriched uranium, and thorium are presented together with empirical equations and plots correlating total fission product activities and/or decontamination factors. Fluxes of 1012-1015 are considered.
Date:
March 28, 1956
Creator:
Arnold, E. D.
System:
The UNT Digital Library
HRP Radiation Corrosion Studies
A fifth in-pile loop experiment, L-4-8, was completed. The loop operated in-pile for a total of 1637 hr, during which time the LITR energy output was 4377 Mwhr. The average fission power in the loop based o cesium analyses was 622 w when the LITR was at full power (3 Mw). Based on oxygen data, the generalized corrosion rate for the first 300 hr was 4.0 mpy; the rate for the remaining 1357 hr was 0.7 mpy. The nickel data gave parallel results. The corrosion of the type 347 stainless steel, Zircaloy-2, and Ti-55AX [unintelligible] exposed in the core and in in-line holders was generally consistent with that observed in previous in-pile loop experiments. Some differences with steel were attributed to the fact that this was the first loop containing steel specimens operated with 0.04 m H2SO4 present in the uranyl sulfate charge solution (0.17 m UO2SO4, 0.03 m CuSO4). Stress specimens, made from the alloys Zircaloy-2, type 17-4 PH stainless steel, and Ti-C-130-AM, were exposed in care, in-line, and pressurizer locations. Microscopic examination and average weight loss gave no indication of effects attributable to the stressed condition of the specimens.
Date:
August 21, 1956
Creator:
Baker, J. E.; Bradley, N. C.; Jenks, G. H.; Olsen, A. R.; Savage, H. C. & Walter, F. J.
System:
The UNT Digital Library
Chemistry Division Semiannual Progress Report for Period Ending December 20, 1955
Semiannual Progress report of the Oak Ridge National Laboratory Chemistry Division providing updates on various projects, experiments, and other work in inorganic and physical chemistry, nuclear chemistry, organic chemistry, chemical physics, chemistry of separation processes, radiation chemistry, and reactor chemistry.
Date:
April 13, 1956
Creator:
Taylor, E. H. & Bredig, M. A.
System:
The UNT Digital Library
Biology Division Semiannual Progress Report for Period Ending February 15, 1956
Progress report of the Oak Ridge National Laboratory Biology Division providing updates on various projects, experiments, and other work. This report includes a summary of scholarly output from the division and departmental activities in cytology and genetics, mammalian genetics and development, microbial protection and recovery, mammalian recovery, pathology and physiology, general physiology, biochemistry, enzymology and photosynthesis, microbiology, plant biochemistry, and biophysics.
Date:
April 20, 1956
Creator:
Hollaender, Alexander & Carson, Stanley F.
System:
The UNT Digital Library
High-Thermal-Conductivity Fin Material for Radiators
This report is the result of a study to develop heat-resistant fin materials possessing a high thermal conductivity for air radiators. Since an economical and commercially feasible product was desired, the investigation was restricted primarily to a study of electroplated copper, clad copper, and copper alloys. Sheet material 0.008 to 0.010 in. thick was evaluated for fabricability and for metallurgical stability and thermal conductivity at 1500°F. From the results of the rests it was concluded that: (1) electroplates were unsatisfactory; (2) clad-copper fins possessing a thermal conductivity of 50% of that of copper are commercially feasible; (3) copper-aluminum alloys possessing a thermal conductivity approaching that of copper at 1500°F are possible. Service tests of clad copper and the copper-aluminum alloys indicate that the choice of materials will be dictated by the requirements of the radiator, since each presents some unique problems.
Date:
January 24, 1957
Creator:
Inouye, H.
System:
The UNT Digital Library
Analytical Chemistry Division Semiannual Progress Report for Period Ending April 20, 1954
Progress report of the Oak Ridge National Laboratory Analytical Chemistry Division providing updates on various projects, experiments, and other work in ionic analyses, analytical instrumentation, radiochemical analyses, activation analyses, spectrochemical analyses, inorganic preparations, optical and electron microscopy.
Date:
July 5, 1956
Creator:
Kelley, M. T.; Susano, C. D. & Raaen, H. P.
System:
The UNT Digital Library
Metallurgy Division Semiannual Progress Report for Period Ending October 10, 1955
Progress report of the Oak Ridge National Laboratory Metallurgy Division providing updates on various projects, experiments, and other work. This report includes a summary of nondestructive testing, physical chemistry of corrosion, fundamental physico-metallurgical research, HRP metallurgy, process metallurgy, metallurgical materials and processing, metallography, and ceramics research.
Date:
June 14, 1954
Creator:
Manly, W. D.
System:
The UNT Digital Library
HRT Reactor Hazards
Several potential hazards that have been recognized and anticipated in the design and fabrication of the pressure vessel in the Homogeneous Reactor Test are discussed. These hazards results from the high operating pressure and temperature of the reactor, the exposure of the reactor vessel material to potential embrittlement and other affects of fast-neutron irradiation, and the need for containment of corrosive flowing liquids. The steps taken in recognition of these hazards are also discussed. The applicability of present codes to the reactor vessel fabrication is considered. Additional fields are suggested where recommended practices developed by code writing bodies could assist in development-type reactor design and fabrication.
Date:
August 3, 1956
Creator:
Miller, E. C.
System:
The UNT Digital Library
Aircraft Nuclear Propulsion Project Quarterly Progress Report for Period Ending June 10, 1956 [Declassified Version]
Progress report of the Oak Ridge National Laboratory Aircraft Nuclear Propulsion Project providing updates on various projects, experiments, and other work. This report includes summaries of project activities in: aircraft reactor test design, ART physics, ART instruments and controls, component development and testing, procurement and construction, ART, ETU, and in-pile loop operations, phase equilibrium studies, chemical reactions in molten salts, physical properties of molten materials, production of fuels, compatibility of materials at high temperatures, chemistry, analytical chemistry, metallurgy, dynamic corrosion studies, general corrosion studies, fabrication research, welding and brazing investigations, mechanical properties studies, ceramic research, nondestructive testing studies, heat transfer and physical properties, radiation damage, fuel recovery and reprocessing, critical experiments.
Date:
September 4, 1956
Creator:
Jordan, W. H.; Cramer, S. J.; Miller, A. J. & Savelainen, A. W.
System:
The UNT Digital Library
Basic Gamma-Ray Data for ART Heat Deposition Calculations
In order that fairly accurate thermal stress calculations can be made on the ART, it is necessary to have a reasonable picture of the temperature distribution in the reactor. To get the temperature distributions, and to determine cooling requirements in various parts of the reactor, one must know the heat deposition rates due to alpha particles, beta rays, gamma rays, and neutrons in all parts of the reactor. The present report contains only the basic physical data necessary to determine the heat deposition rates due to gamma rays. Neutron fluxes in the core and reflector regions of the ART are to be obtained from two-dimensional multigroup calculations (performed by the Curtiss-Wright Corporation). These fluxes, in conjunction with the neutron absorption cross sections, determine the neutron capture and inelastic scattering rates in the core and in the reflector. The data in this report permit the calculation of the number of gamma rays originating at various energies at every point in the core and reflector.
Date:
October 3, 1956
Creator:
Bertini, H. W.; Copenhaver, C. M.; Perry, A. M. & Stevenson, R. B.
System:
The UNT Digital Library
A Physical Property Summary for Fluoride Mixtures
This report presents a summary of certain physical properties that have been determined experimentally on the fluoride mixture that have been formulated at ORNL (Rers. 1, 2). These properties include the density, enthalpy, heat capacity, heat of fusion, thermal conductivity, viscosity, Prandtl number, electrical conductivity and surface tension. In addition to the experimental data, values have been predicted for the heat capacity and density of the other mixtures from the correlations of these properties. Estimates of the viscosity have also been made for a number of the mixtures on which no experimental data were available.
Date:
September 5, 1956
Creator:
Cohen, S. I.; Povers, W. D. & Greene, N. D.
System:
The UNT Digital Library
Stable Isotope Research and Production Division Semiannual Progress Report
The Spectroscopy Research Laboratory is concerned with research and development in the fields of nuclear magnetic resonance, microwaves, infrared and optical spectroscopy, spectrochemistry, and x rays. Research is directed toward fruitful methods of isotope analysis; new element and compound analytical methods having application to immediate Laboratory or long-range commission needs; and fundamental research on isotopes, elements, and compounds. The work is reported on a project basis to give a more complete picture of the purpose, activity, and status of each program. More detailed information on reported or inactive projects may be obtained from the previous semiannual report.
Date:
February 18, 1955
Creator:
Keim, C. P.
System:
The UNT Digital Library