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The Stability of Purex Solvent to Radiation and Chemical Attack

Description: The effects of variables on the rate of Purex solvent deterioration were investigated with the emphasis on those deterioration products which cannot be removed by carbonate washing. The deterioration rate was found to be directly proportional to the acid and nitrate ion concentrations, and proportional to the square root of the concentration of nitrite ion. Other observations on the effects of temperature, relative merits of brand name solvents, and the effects of radiation are included. A method of calculating the equilibrium level of the solvent deterioration products based on study conclusions and various estimates is outlined. (J.R.D.)
Date: May 24, 1955
Creator: Swanson, J. L.

Technology of Non-Production Reactor Fuels Reprocessing Budget Activity 2790. Quarterly Report

Description: Sawing studies were made using a dry function blade for cutting Zircaloy taking. An off-gas filtration system including a rotoclone and a filter assembly was installed to permit studying of the particulate material generated during the friction cutting operations. Studies of mechanical techniques for safety processing the Na or NaK alloy reservoirs present in some non-production fuels have continued. Stainless steel-clad swaged U0/sub 2/ rods and stainless steel- clad U- 10 wt.% Mo alloy rods were sheared under water to investigate the mechanical and particulate handling problems associated with these two major components of the power reactor fuels reprocessing program. The behavior of explosive U- Zr residues in the Zirflex Process was studied. In dissolution of stainless steel cladding from U0/sub 2/ it was found that a more rapid initial U0/ sub 2/ dissolution by H/sub 2/SO/sub 4/ occurred if the U0/sub 2/ was exposed to the atmosphere. Farther studies on the dissolution of ingot U and sintered U0/ sub 2/ in HNO/sub 3/ and HNO/sub 3/- ferric nitrate are reported. The dissolation of U-Mo alloys is being studied. The corrosion of 304-L stainless steel and Hastelloy-F in nitric acid-ferric nitrate systems was studied. Exploratory experiments were done attempting to define the effect of Al(NO/sub 3/ )/sub 3/ and HF on the formation of explosion sensitive surfaces during the dissolution of U - low Zr alloys. Studies of metallic U dissolution in dilute aqua regia were made. Niflex (HNO/sub 3/- HF) dissolution studies of 304 stainless steel were continued. (W.L.H.)
Date: July 1, 1959
Creator: Cooper, V. R.

Transformation Kinetics of Plutonium. Part 1. A Study of the Beta to Alpha and Alpha to Beta Transformations

Description: The transformation kinetics of alpha and beta plutoniunn were determined by using a fluid displacement technique. The rate of formation of the alpha phase from the beta phase was determined after beta heat treating and allowing the sample to transform isothermally in the alpha range. Isothermal reaction curves were obtained from --78 to +90 d C. A time- temperaturetransformation curve showed the maximum rate of transformation to be approximately --20 d C. The beta phase did not transform completely to the alpha when the transformation was allowed to take place isothermally. A relationship between the fraction untransformed beta and the transformation temperature has been established. Isothermal reaction curves and a time- temperature-transformation curve of the alpha at 200 deg C an - BETA transformation were obtained. Portions of the timetransformation curves of the BETA at 200 deg C an alpha transformation of four purities were plotted. The effects of beta heat treating times and temperatures were studied. Photomicrographs of a specimen having transformed from the beta to the alpha phase at different rates of transformation are presented. (auth)
Date: April 17, 1958
Creator: Nelson, R. D.

Transformation Kinetics of Plutonium. Part 2. A Study of the Gamma to Beta to Alpha and Alpha to Beta to Gamma Transformations

Description: The kinetics of the gamma deg C was con- beta deg C was con- alpha , beta deg C was con- gamma , and alpha deg C was con- beta deg C was con- gamma transformations were determined with a fiuid displacement technique. The rates of formation of the alpha and beta phases from the gamma phase were determined after gamma heat treating and allowing a sample to traasform isothermally in the alpha and beta ramges. Isothermal reaction curves were obtained from 160 C to -78C. The time-temperature-transformation curve of the gamma deg C was con- beta deg C was con- alpha transformation was plotted. The effect of the gamma heat treating time and temperature on the rate of transformation was examined. Isothermal reaction curves and time-temperature- transformation curves of the beta deg C was con- gamma , and alpha deg C was con- beta deg C was con- gamma transformations were plotted. Photomicrographs of specimens having transformed from the gamma range at different rates of transformation are presented. (auth)
Date: July 18, 1958
Creator: Nelson, R. D.

Uniform Aqueous Corrosion of Aluminum--Effects of Various Ions

Description: The most important variable in water quality on the uniform corrosion of Al was the pH. Solutions of distilled water containing phosphate ions and citrate ions were the only media which showed a definite specific ion effect. Phosphate inhibited the corrosion and citrate increased it. Oxalate ions appeared to increase corrosion, but the effect is not definitely demonstrated by the data. Corrosion was dependent only on pH in tap water, reactor process water, distilled water, and distilled water containing up to 100 ppm of chloride, nitrate, sulfate, bicarbonate, hydrogen peroxide, acetate, arsenate, silicate, dichromate, molybdate, and mixtures of these ions. Solutions of up to 10,000 ppm chloride in distilled water showed no specific ion effect upon uniform Al corrosion. The effects of 0 to 10 ppm of dichromate and phosphate ions were investigated over the range pH 4 to pH 7. Phosphate at 10 ppm inhibited corrosion in solutions containing up to 2 ppm of dichromate, but at 10 ppm dichromate the phosphate does not appear to inhibit corrosion. Also at 10 ppm dichromate, the effect of pH is diminished over the range pH 4 to pH 7. Corrosion rates varied with the flow rates of the test solutions at low flow rates, and were lowest at the lowest flow rates. This effect was attributed to the buildup of aluminate ion conconcentration in the lower flow systems. Short term corrosion tests at 92 deg C revealed major specific ion effects. Minor effects were lost in experimental uncertainties. The inhibiting effect of phosphate under these conditions has been shown to exist over longer exposures at higher temperatures. (auth)
Date: June 10, 1957
Creator: Troutner, V. H.

The Zirflex Process

Description: tive dissolution of zirconium or Zircaloy fuel cladding. The process involves the dissolution of the cladding material in solutions of ammonium fluoride alone or in mixture with amonium nitrate. Mixtures of amonium fluoride and amonium nitrate are preferred since they result in very little evolution of hydrogen during the is that these solutions attack austenitic stainless steels only slowly, in sharp contrast to the media (e.g., hydrofluoric acid or hydrofluoric-nitric acid mixtures) generng 6 M NH/sub 4/F, the rate of pentration of Zircaloy-2 is nearly 100 mils/hr, while that of typical austentic stainless steels is only about 0.5 mil/month. (auth)
Date: October 31, 1958
Creator: Swanson, J. L.

Irradiation Annealing in Graphite. [Part] 2. Activation Processes

Description: The rate of annealing due to primary neutron-carbon atom collisions transferring 3 to 25 ev to the recoil atoms is much too slow to accouat for irradiation annealing rates observed in pile annealing experiments. It is necessary to assume that much of the annealing is accomplished by the slowing down of carbon atoms produced by high energy neutrons. The fraction of primary recoil energy going into arealing reactions is estimated to be about four per cent. Irradiation annealing occurs before vibrational equilibrium is established with the lattice and should not be considered as equivalent to additional thermal arealing. Irradiation damage to the properties of graphite should saturate when the irradiation damage rate equals the irradiation and thermal annealing rates. The effects of irradiation annealing on the damage distribution function are discussed. (auth)
Date: February 26, 1958
Creator: Townsend, J. R. & Nightingale, R. E.

A Martensitic Reaction for Uranium

Description: Hardness measurements of specimens quenched from the beta yields alpha phase at different cooling rates support the proposed martensitic beta yields alpha transformation for urnnium. Specimens held in 635 and 600 deg C isothermal baths prior to subsequent quenching to --5 deg C require more than 10 and two seconds, respectively before diffusion mechanlsms for beta yields alpha transformation commence. Once started, about 500 seconds are required to complete transformation by diffusion at these temperatures. Specimens quenched prior to tais hold time transform in part martensitically. Relationships are calculated for hardness as a function of grain size and cooling rate, and for grain size as a function of cooling rate. Metallographic examination confirms the hardness trends and reveals that widely varied grain structures can be produced by controlled cooling from the beta phase. Finally, a schematic time- temperature-transformation curve is sketched from the hardness data obtained. (auth)
Date: June 25, 1957
Creator: Bement, A. L. & Wallace, W. P.

Notes Pertaining to Recuplex Product Evaporation

Description: A red-brown liquid formed during the evaporation of simulated Recuplex product solutions containing plutonium, nitric acid, carbon tetrachloride, and tributyl phosphate (TBP). The liquid is soluble in carbon tetrachloride. Concentration of solutions containing a TBP to plutonyl nitrate weight ratio of 0.15 or greater to a pot temperature of 150 deg C caused reactions which produced enough heat to bring the pot contents to a red heat with copious evolution of gases. Evaporation path curves and boiling point data were obtained from batch evaporations with minimum reflux and are presented. Polymeric plutonium(IV) was formed upon concentrating plutonium nitrate solutions of low nitric acid content. The region of polymer formation was defined and is presented. (auth)
Date: April 28, 1954
Creator: Pugh, R. A.

OXIDATION OF PLUTONIUM (III) BY SODIUM NITRITE

Description: The reaction velocity constant for the oxidation of Pu(III) by nitrite in HNO/sub 3/ solution containing ferrous sulfanate is given. The reaction rate was found to be measurable by means of spectrophotometry. The data indicate the reaction to be a pseudo first-order reaction in the region of HNO/sub 3/ and nitrite concentration of interest. The reaction velocity constant, expressed as a first-order reaction with respect to Pu, was found for several values of HNO/ sub 3/ and nitrite concentrations. The HNC/sub 3/ reaction velocity constant relationship is given. The oxidation of the ferrous sulfamate--Pu(III Pu(III) solution proceeds successively through the sulfamate, ferrous, and Pu(III) ions. An autocatalytic mechanism is asscciated with the oxidation of both ferrous and Pu ions which obviates the possibility of simple calculations of constants based on nitrite concentration. An empirical relationship between the reaction velociiy constant and the (added) nitrite concentration is given. (auth)
Date: July 17, 1957
Creator: Brunstad, A.

Ax-1, a Computing Program for Coupled Neutronics-Hydrodynamics Calculations on the Ibm-704

Description: The presentation includes a very general outline of the program, a semi- detailed flow diagram which emphasizes the physics and control aspects of the calculation, and then a detailed flow diagram and listing of the program (which is written in Fortran). Explanatory notes accompany thc diagrams. Following the notes on the program, master lists detailing thc roles of the sense switches, sense lights, pauses, and stops are presented. The operating instructions are then given, followed by a sample problem, including detailed information on input data. The theoretical discussion has been kept primarily in the appendices, and is generally in outline form with references, rather than in full exposition. (auth)
Date: May 1, 1959
Creator: Okrent, D.; Cook, J. M.; Satkus, D.; Lazarus, R. B. & Wells, M. B.

Debye-Huckel, Thomas-Fermi Theory of Plasmas and Liquid Metals: Numerical Solution

Description: A Debye-Huckel-type theory is described for an assembly of completely ionized atoms, the nuclei being treated classically and the electrons by the Thomas-Fermi method. The thermodynamic functions are derived by considering the Debye chnrging process, and the virial theorem is shown to hold. Numerical results are given for hydrogen and iron near normal solid densities, and are probably accurate only at high temperatures (kT > 5 ev for hydrogen and kT> 100 ev for iron). (auth)
Date: January 1, 1957
Creator: Cowan, R. D. & Kirkwood, J. G.