42 Matching Results

Search Results

Advanced search parameters have been applied.


Description: The general prospects of several radioisotopes are reviewed; the special properties of U/sup 232/ and Th/sup 228/ are poi nted out; and ionium (Th/sup 230/ ) and protactinium target materials are discussed from the sthndpoint of availability and chemical separations processes required for the preparation of U/ sup 232/ and Th/sup 228/. Outlines are given for potential schem es for the separation of U/sup 232/ and Th/sup 228/ from uranium milling pr ocess waste streams and from the irradiation products of Th/sup 230/--Th/sup 232/ mixtures. The high heat generating rates of these potent alpha emitters make them especially suitable for primary consideration as heat sources for small thermoelectric generators. The exceptionally high alpha activity suggests their use in special neutron sources as Ra-Be sources, and they may have sufficiently high neutron generating rates to be in contention with some of the smaller research reactors and experimental neutron producers. (B.O.G.)
Date: December 15, 1959
Creator: Coppinger, E.A. & Rohrmann, C.A.
Partner: UNT Libraries Government Documents Department


Description: >The proposed flowsheets for reprocessing of nonproduction fuels include centrifugal separation of particulate matter from various dissolver effluent solutions. The settling characteristics of process solids were determined in water and in cold process solutions. Uranium dioxide particles will be recovered from Zirflex and Sulfex cladding waste solutions, and core-dissolver solutions will be centrifuged for removal of ZrO/sub 2/, metallic slimes, siliceous matter, and uranium-bearing solids. (W.L.H.)
Date: December 1, 1959
Creator: Amos, L.C.
Partner: UNT Libraries Government Documents Department


Description: A concentration cell electrode was installed in a fritted glass surface and was used to measure the surface KCl concentration while water was being transpired through the surface into a mixed tank of 0.1 M KCl. The results from the first Fluorox run made with crude UF/sub 4/ showed that 85.3% of the theoretical amount of UF/sub 6/ was accounted for, with 17.9% being collected in cold traps and the remainder being consumed in various side reactions. Installation was completed of apparatus to study the electrolytic removal of nickel on an engineering scale from concentrated HRT fuel solution. An extremely low yield stress of 0.02 lb/sq ft was measured for a thoria-urania slurry containing 2.5 wt.% Al/sub 2/O/sub 3/ and spherical particles of 1.7 micron mean diameter. Preliminary data on the rate of uranium sorption on Dowex 21K from sulfate solutions were correlated with a simple spherical diffusion model. Laboratory scale studies to determine the effect of reflux time, HNO/sub 3/ concentration, and air sparge on chloride removal from APPR-type Darex dissolver product showed that an air sparge is definitely beneficial in chloride removal. Preliminary cyclic cleaning tests showed that boiling 25% caustic solution was adequate for cleaning type F (20 micron) porous metal filter elements fouled in the absence of filter aid with siliceous sludge from Darex solvent extraction feed solutions. Sections of unirradiated stainless steel-clad UO/sub 2/, sheared into lengths of 1/2 in., 1 in., 2 in., and 2 3/4 in., were leached free of UO/sub 2/ with 10 M HNO/sub 3/ in 30, 45, 60, and 75 min, respectively. The abrasive blade cost for the removal of inert end adapters from selected reactor assemblies ranges from 12 for the Gas-Cooled Reactor to 19 for Consolidated Edison. A zirconium dissolution was carried to completion at 600 ction prod- ...
Date: July 21, 1959
Creator: Bresee, J.C.; Haas, P.A.; Horton, R.W.; Watson, C.D. & Whatley, M.E.
Partner: UNT Libraries Government Documents Department


Description: The concentration gradients of uranyl ion in aqueous and organic solutions were analyzed by taking a macro photograph of the desired gradient by monochromatic (436 m mu ) light transmitted by the solution normal to the gradient in an appropriate diffusion cell. Two Druhm runs were terminated due to malfunction of the sodium metering system and the third run was terminated when the UF/sub 6/ nozzle ruptured. Calculations of particle temperature versus time relations for the flame denitration-calcination method of preparing metallic oxide from nitrate solutions indicate that the times required for heat transfer are controlled by the rate of radiant heat transfer to particle surfaces instead of by conductive heat transfer within the particles. A completed experimental study indicated that electrolysis in a cell with a mercury cathode and a platinum anode is a practical process for removing nickel from HRT fuel solution. The apparent diffusion coefficient of uranium loading on Dowex 21K was shown to be directly related to the resin size. An explosion of sufficient violence to blow apart the Pyrex pipe dissolver occurred during the fifth Darex dissolution of simulated SRE fuel probably from a rapid gas phase reaction between hydrogen and oxidizing gases such as NO/sub 2/. Materials handling flowsheets were completed for (A) decladding, washing, recanning and storing spent SRE uranium fuel slugs and (B) the shearing and leaching of stainless steel clad UO/sub 2/ and UO/sub 2/- ThO/sub 2/ fuels. A literature survey is being conducted dealing with reactor coolant and coolant loop contamination and decontamination. During run R-17 for calcination of evaporated Darex waste, the same as run R-16 which deformed the bottom calcination vessel except that one of the three added pressure probes was vibrated to keep it unplugged, the bottom of the calcination vessel did not deform, and there was ...
Date: December 31, 1959
Creator: Bresee, J.C.; Haas, P.A.; Horton, R.W.; Watson, C.D. & Whatley, M.E.
Partner: UNT Libraries Government Documents Department


Description: Two alternate systems, acetic acid-nickel and acetic acid-cobalt, were examined for possible replacement of the corrosion system: ferric chloride-nickel which is being used in the current transpiration corrosion protection studies. Two Fluorox fluidized bed runs were made, of 9 and 58 hr duration, in which dry air and oxygen were used as oxidizing and fluidizing gases. Tests of the hydroclone classification of thoria indicated that more than 95% of the +0.5 micron particles can be removed from a sample if 50% recovery of the -0.5 micron particles is acceptable. Fluidized bed denitration of ThNT did not produce large dense ThO/sub 2/ particles, but flame denitration of mixed thorium-uranium- aluminum nitrates produced spherical particles. Three alternate batch Darex flowsheets gave chloride removal to less than 350 ppm with 61% nitric acid feed, while dissolution studies of APPR fuel elements showed that complete dissolution of braze metal in aqua regia may be difficult. Leaching studies of unirradiated UO/sub 2/ pellets showed that the most important variable effecting dissolution rate was the total nitrate content of the dissolvent. Delivery of tae SRE decanning equipment was scheduled for April 1, 1959. Temperatare increases in cylinders of solid radioactive waste were calculated for APPR fuel processing using a Darex flowsheet and cooling times ranging from 1 to 8 yr. (auth)
Date: April 30, 1959
Creator: Bresee, J.C.; Haas, P.A.; Horton, R.W.; Watson, C.D. & Whatley, M.E.
Partner: UNT Libraries Government Documents Department


Description: The existence of one or more long-lived nonmetastable excited states of argon in the 15 to 15.5 ev range has been indicated. The increased ionization observed when certain impurities are added to argon is attributed to this long lived excited staate rather than to molecular argon or subexcitation electrons. A competitive process between optical decay and ionizing collisions was evidenced by spectral analysis of the gas mixtures. From these experiments it was not possible to determine the exact energy levels of the suggested long-lived excited states. (auth)
Date: October 23, 1959
Creator: Sanders, F.W.; Hurst, G.S. & Bortner, T.E.
Partner: UNT Libraries Government Documents Department


Description: Numerous types of high temperature ceramic fuel elements for the Pebble Bed Reactor are being evaluated. Specimens are 1 1/2 in. diameter uranium graphite spheres with external coatings such as silicon carbide or pyrolytically deposited high density graphite and fuel particle coatings such as alumina. Low fission product leakage rates at high temperatures have been observed for some of these coatings. High-level irradiation has given no visible evidence of radiation damage to either the silicon carbide coating or the coating-graphite bond. (auth)
Date: November 30, 1959
Partner: UNT Libraries Government Documents Department

Automatic Reader for Air-Monitoring Filter Paper

Description: An automatic reader was developed for scanning 4 x 9in. filter papers from systems that monitor particulate airborne activity. Paper tape shows alpha and betagamma activities, together with counting times and identifying data, for any samples exceeding a predetermined value a special indicator mark is added. (auth)
Date: September 28, 1959
Creator: Thaxter, M. D. & Taussig, Thomas
Partner: UNT Libraries Government Documents Department

Physics Division Summary Report for July-August 1959

Description: Experiments done wIth the Van de Graaff generator are listed. Improvements and generator troubles are discussed. Most of the small resonances up to 350 kev in Na/sup 24/ were studied by self-detection measurements and the analysis of the resonances is in progress. The analyses were completed in the region from 180 to 350 kev and the results are included. Preliminary studies on dissociation of multiple-changed DBr/sup 80/ ions formed by isomeric transition ot 4.4-hr Br/sup 80m/ indicate that less than 5% of the DBr ions of each charge greater than +3 remain bound. Atomic ions or Br with charges from +1 to +10 were observed. The complete crystal structure of sodium uranyl acetate was determined. The dimensions of the Li/sub 2/WO/sub 4/ unit cell were measured. A precise determination of all atomic positions is under way. It was found that the statistical properties of the excited states of some complex atoms are the same as those which have previously been discussed for neutron resonance states. The assumption that space-time possesses the symmetry of the DeSitter group is being studied to develop the physical consequences for the properties of elementary particles. A possible formalism that explains the difference between the masses of the charged and neutral species of both pi - and K-mesons is proposed. (for preceding period see ANL-6020.) (auth)
Date: August 1, 1959
Partner: UNT Libraries Government Documents Department


Description: The variations of size and density of aerosol particles were examined. Experiments were made with a wide variety of substances using a modification of Whytlaw-Gray and Patterson's methods in which freefall velocity was determined. The mass was estimated both by balancing the gravitational and electrostatic forces and from rising velocities under constant field strength. The results were compared with the shape and structure of the aerosols shown by electron microscopy. The variation of the Stokes' (or drag) diameters was found by combining the results with cascadeimpactor and microscope measurements. A modification of the Millikan oil drop apparatus was used. It was concluded that the free-fall velocity of an agglomerate is proportional to the two-thirds power of its mass, and when primary particles are not uniform in size and shape, wide variation in agglomerate densities occur. It was also noted that when primary particles have irregular shapes there is a difference in drag diameter of the agglomerate determined from the rising and falling velocities. This is a factor in electrical precipitation of such aerosols. (J.R.D.)
Date: March 1, 1959
Creator: Johnstone, H.F.
Partner: UNT Libraries Government Documents Department


Description: APPR-type dispersion fuel element specimens containing temperature to respective burnups of approximately 50, 20, and 20% of uranium with no evidence of gross dimensional changes or loss of structural integrity. Blistering and/or core cracking has occurred when sections of 17.9 wt.% UO/sub 2/ specimens irradiated to burnups over 40% of uranium were subjected to post-irradiation annealing at 600 deg F for 24 hours. Post-irradiation core hardness measurements indicate that significant differences in irradiation damage exist between the various specimen types. These data indicate that the effects of the fabrication variables investigated in this program are as follows: The severity of irradiation damage in dispersion type fuel elements is inversely proportional to the UO/sub 2/ particle size of the fabricated plate. The particle size of the UO/ sub 2/ powder used in preparation of the initial core compact and the method of preparation of the UO/sub 2/ powders largely determine the final UO/sub 2/ particle size of roll-bonded, dispersion fuel plates. The particle size of the stainless steel powder used in the initial core mixture and the degree of cold reduction during final sizing of the fuel plate are apparently of relatively minor importance, at least for the systems investigated in this program. The severity of irradiation damage is directly proportional to the fuel concentration. Where an increased fuel loading is accompanied by an increase in the loading of the B/sub 4/C burnable poison to facilitate reactor control, the possibility of serious irradiation effects is increased to an even greater degree. (auth)
Date: March 1, 1959
Creator: Richt, A.E.
Partner: UNT Libraries Government Documents Department


Description: ABS>Progress is reported in the following studies: the decay time of irradiated scintillation solutions; the performance of twin scintillation detectors for measuring neutrons in the presence of gamma radiation; the measurement of cosmic ray neutron background with a twin scintillation fast neutron spectrometer; the diffusion and absorption of gases in plastic-walled ionization chambers; calculations of the drift velocity and the energy distribution of electrons of helium, neon, argon, and nitrogen under the action of a uniform electric field; the development of equipment for tracer studies of atmospheric diffusion; the deposition and retention of isotopes of actinium, radon, radium, and thorium in bone; the effects of age on calcium metabolism in bone,; the development of a mathematical theory of the retention of radioactive elements by bone; the development of a reproducible method for directly determining individual alpha activities in mixtures; the design of a flow-gas Geiger counter; a survey of the natural radioactivity of a number of municipal water supplies; measurements of activity in individuals by means of the human spectrometer; measurements of the cesium-l37 content of human subjects; measurements of the atmospheric content of cesium-137 as a function of time; a comparison of background radioactivity at the Laboratory and a site approximately 250 feet below grade level; development of a spectrometric method for measurements of radioactivity in soil; the effects of meteorological variables on the distribution of radon in the atmosphere; and studies of atmospheric diffusion. A list of publications during the period is included. (For preceding period see ANL-5919.) (C.H.)
Date: May 1, 1959
Partner: UNT Libraries Government Documents Department


Description: The so-called Collisionless Boltzmann Equation'' or Vlasov Equation'' has been derived previously by Harris by use of a complete statistical treatment of both the plasma particles and the electromagnetic fields. It is shown that a consequence of this approximation is that the entropy of the electromagnetic field as well as that of the plasma particles is a constant. This result is used to demonstrate that only completely the Vlasov equation. (auth)
Date: October 1, 1959
Creator: Harris, E.G. & Simon, A.
Partner: UNT Libraries Government Documents Department

Instantaneous Velocity Profile Measurement by Photography

Description: An apparatus is described for using phosphorescent particles to enable photographic determination of qualitative and quantitative instantaneous velocity profiles in flowing liquids. Phosphor and film data are tabulated, and factors to be considered in analysis ot the photographs are discussed. (J.R.D.)
Date: August 17, 1959
Creator: Hoffman, H. W.
Partner: UNT Libraries Government Documents Department


Description: A study of the stored energy buildup in the MTR reflector graphite and a program of controlled energy release is presented. Calculations, based on measurements of samples from the pebble zone show that an inadvertent spontaneous stored energy release would cause a temperature rise of 90 deg F in the pebble zone. The maximum transient structure temperatures resulting from a worst credible accidental release of energy would be less than allowable at present (except for possible damage to neutron detector chambers) but could exceed this value in five years. It is proposed that the stored energy be released by thermal annealing. The reflector graphite is heated by reducing the air flow and operating the reactor at low power until a temperature of 500 deg F is reached, at which point the reactor is scrammed. Normal cooling is provlded after 15 minutes at peak anneal temperature or if the temperature rises to 600 deg F. Health physics monitoring includes continuous measurement of particulate and of Ci/sup 4/ activity. Sustained oxidatlon, if it occurs, wlll be detected with a C0/sub 2/ monitor and controlled by smothering. An estimated 2 or 3 days of MTR operating time will be needed of which the anneal itself wlll require about one day. (auth)
Date: December 9, 1959
Creator: Fast, E.; Smith, E.O. & Ford, J.D.
Partner: UNT Libraries Government Documents Department

Radiation Hazards From Recycled Reactor Fuel

Description: The radiation hazards associated with recycled nuclear reactor fuels will greatly complicate the handling and refabrication of these fuels. This problem is most serious with U/sup 233/ and Pu fuels where the presence of U/sup 232/ and thue heavier isotopes of Pu contribute energetic alpha, gamma, and neutron radiations at levels many times that from isotopically pure U/sup 233/ and Pu/sup 239/. Present knowledge of the radiation hazards associated with recycled fuel and the additional data needed to make a thorough evaluation of these hazards are summarized. (auth)
Date: June 1, 1959
Creator: Arnold, E. D.
Partner: UNT Libraries Government Documents Department


Description: BS>A previous calculation of the rate of diffusion of like charged particles across a magnetic field is generalized. No "a priori" assumption as to the relative magnitude of certain terms need be made and spatial density gradients are permitted in both directions perpendicular to the field. The final result agrees with that given earlier. (auth)
Date: November 27, 1959
Creator: Isihara, A. & Simon, A.
Partner: UNT Libraries Government Documents Department


Description: Thorium oxide is formed by the calcination of thorium oxalate precipitated under carefully controlled conditions. Material is produced with mean particle diameters of 1 to 5 mu . Some of the thorium oxide had uranium added to it by decomposing uranyl carbonate on the thorium oxide followed by calcination. Most of the oxides prepared were calcined to 1000 deg C or more and size classified to remove particles greater than 10 mu . The oxides were prepared in 150-lb batches, with a complete cycle requiring 24 hr. (auth)
Date: December 22, 1959
Creator: Johnsson, K.O. & Winget, R.H.
Partner: UNT Libraries Government Documents Department


Description: A 3-inch-diameter flame tower for the conversion of uranosic oxide to uranium hexafluoride with elemental fluorine was tested for possible use in the fluorination step of the present uranium recovery process. The oxide was fed from a hopper to the tower by a screw feeder. The fluorine and the oxide entered at the top and flowed concurrently down through the tower. The unreacted or partially reacted oxide was collected in an ash receiver at the bottom. Fine solid particles were removed from the gas stream by an electrostatic precipitator and a tune-type filter. The uranium hexafluoride was collected in cold traps. Twenty-five experimental runs were conducted with average oxide feed rates from 3.73 to 19.38 lb/hr. The average fluorine flow rates were from 7.5% below to 44% above the stoichiometric amount of fluorine required. The best operating conditions were at a feed rate of 15 lb of oxide per hour with a minimum fluorine excess of 75% 110.6 lb of fluorine per hr). The material collected in the tower ash receiver represented between 6.0 and 10.0 percent of the total amount of uranium fed during the run. The ash, combined with an equal weight of oxide, can be fed back to the tower. The electrostatic precipitator wns capable of collecting up to 92% of the solids in the gas stream. A porous-tube filter worked best for the removal of the remaining particles in the gas stream. The experimental runs have shown that uranosic oxide can be satisfactorily converted to uranium hexafluoride in a 3-in.-diameter flame tower of simple design. The present conversion rate of uranosic oxide, approximately 4 lb per manhour with the tube reactor, could be increased to 10 lb per manhour by using the flame tower. (auth)
Date: August 28, 1959
Creator: Peoples, L.C.
Partner: UNT Libraries Government Documents Department


Description: Neutral hyperons produced by 5-Bev The effects of /sup -/ mesons incident on a large propane bubble chamber are analyzed in detail with respect to production cross sections and angular distributions of production and decays and the A lifetime is measured. The cross section for neutralhyperon (Y/sup 0/) production by the reaction The effects of /sup -/ + p 1100 deg C are Y/sup 0/ + K is 0.98 sintering time 0.16 mb. The cross section for carbon mpacting ( The effects of - + C 1100 deg C are Y/sup 0/ + K) is 6.05 sintering time 0.89 mb. The mean Svlvania Electr decay time is (3.12 sintering time 0.34) x 10/sup -10/ sec. The corrected lifetime is observed to be (3.23 sintering time 0.36) x 10/sup -10/ sec. Although the up-down decay asymmetry for Svlvania Electr hyperons is not significantly different from zero, the fore-aft decay angular distribution is asymmetric; alpha P = -0.31 sintering time 0.12 where the decay proton distribrtion along the Svlvania Electr direction of motion has been examined. This is suggested as evidence for nonconservation of parity in the production interaction. The Svlvania Electr -production angular distribution is peaked backward in the production center of mass. The A momentum spectrum and the distribution of Svlvania Electr production star prongs are presented. Sources of bias and their correction are discussed, and an estimate is made of the carbon contamination of the events that contribute to the hydrogen cross section for a production. (auth)
Date: April 13, 1959
Creator: Hotz, D F
Partner: UNT Libraries Government Documents Department