A survey was made of methods potentially useful for the determination of the oxygen to metal ratio in mixed oxides of uranium and plutonium. A gravimetric method was selected as being the most promising for adaptation in a short period of time. Development of the technique resulted in a reliable method which meets the requirements for unirradiated mixed oxide fuel samples. The method, based upon an equilibrium weight at 700 deg C in dry hydrogen, was shown to be capable of measurement of O/(Pu + U) ratios in 20% PuO/sub 2/--80% UO/sub 2/ pellets with a standard deviation of plus or minus 0.001. (auth)

Progress is reported on research directed toward. the development of adhesives, which are compatible with explosives; the measurement of nuclear properties of polonium isotopes; residue adsorption; separation and purification of isotopes; thermal diffusion theory analyses; emission strength analyses for neutron sources; and krypton-85 counting methods development. (B.O.G.)

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Dense UN specimens for property tests were fabricated primarily by an isostatic hot-pressing technique in which consolidated powder sealed in a refractory metal container was subjected to a 10,000-psi external gas pressure at 1480 to 1540 deg C for 3 to 4 hr. The thermal conductivity of uranium mononitride increased from 0.04 cal/(cm)(sec)( deg C) at 200 deg C to 0.06 cal/ (sec)(cm/sup 2/)( deg C) at 1000 deg C, which by an integrated thermal- conductivity criterion, makes it some eight times more effective than UO/sub 2/ in transferring heat. Thermal-expansion coefficients of 9.0 x 10/sup -6/ per deg C and 9.9 x 10/sup -6/per deg C over the ranges 20 to 800 deg C and 20 to 1600 deg C, respectively, were measured. UN retained about 80% of its room- temperature hardness at 1100 deg C. Above this temperature, the hardness dropped rapidly with increasing temperature. The specific heat is cal per g mole can be conveniently described by the equition C = 13.32 + 1.19 x 10/sup -3/ T --2.10 x 10/sup 5/ T/sup -2/ over the range 273 to 142 3 deg K. Electrical conductivity dropped with increasing temperature a metallic characteristic. Anomalies were noted in attempts …

An investigatiori of the annealing of the radioinduced carrier concentration change in Sb-doped Ge in the range 370 to 455 l K was made. The irradiations were conducted at liquid nitrogen temperature using Co/ sup 60/ gamma irradiation. A model that explains the observed behavior is presented. On the basis of the model, the observed annealing consists of vacancy diffusion simultaneously to impurity sites and annihilation centers. Analysis of the activation energy for the annealing process yields values of 0.8 to 1.4 ev in agreement with the range of energies that were attributed to vacancy motion but that cannot be resolved into unique components. The complex activation energy is explained by the model in terms of the impurity concentration. It was observed that the change in carrier concentration saturates before complete annealing is achieved. The saturation, which is stable for further annealing at higher temperatures, is also explained in terms of the model. The vacancies are considered to diffuse to annihilation centers, such as dislocation lines, and to the site adjacent to an Sb atom. Those that go to an Sb are trapped. The Sb- vacancy complex can break up to supply a vacancy back to the system or can …

ABS>A detailed description of the printed output sheets from the intranuclear cascade calculation described in ORNL3383 is given. The three analysis codes --analysis codes I and II and an evaporation code --that were written to organize the raw data of the output tape are considered. (auth) A tabulation of the neutron total cross section of U/sup 233/ as a function of neutron energy from 0.07 to 10,000 ev, measured with the ORNL fast chopper time- of-flight neutron spectrometer is given. (auth)

Distortion of reactor-grade graphites was studied at varying neutron exposures ranging up to 14 x 10/sup 21/ neutrons per cm/sup 2/ (nvt)/sup */ at temperatures of irradiation ranging from 425 to 800 deg C. This exposure level corresponds to approximately 100,000 megawatt days per adjacent ton of fuel (Mwd/ At) in a graphite-moderated reactor. A conventionalcoke graphite, CSF, and two needle-coke graphites, NC-7 and NC-8, were studied. At all temperatures of irradiation the contraction rate of the samples cut parallel to the extrusion axis increased with increasing neutron exposure. For parallel samples the needle- coke graphites and the CSF graphite contracted approximately the same amount. In the transverse direction the rate of cortraction at the higher irradiation temperntures appeared to be decreasing. Volume contractions derived from the linear contractions are discussed. (auth)

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This report summarizes the technical progress on the subject contract for the period March 15 to May 14 1963.

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Production of {Lambda} + K{sup 0}, {Sigma}{sup 0} + K{sup 0}, and {Sigma}{sup -} + K{sup +} by 1170-MeV/c {pi}{sup -} mesons has been studied in the Lawrence Radiation Laboratory 72-inch hydrogen bubble chamber, Cross sections, angular distributions, and polarizations are presented. The polarization of the {Sigma}{sup 0} is determined at four center-of-mass angles and found to be small everywhere. Based on published results for the reaction {pi}{sup +} + p {yields} {Sigma}{sup +}, K{sup +}, a comparison of the polarizations of {Sigma}{sup +}, {Sigma}{sup -}, and {Sigma}{sup 0} is made from the charge-independence triangle. A conclusion is reached that the {Sigma}{sup -} polarization should be large, and that the {Sigma}{sup -} and {Sigma}{sup +} polarizations should be opposite in sign.

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Design and construction specifications to be followed in the development of the reactor, its associated systems and experimental facilities, and the housing and required services for the facility are presented. The testing procedures to be used are outlined. (D.C.W.)

Heavy-ion reactions in the low-Z region were investigated with 27-Mev nitrogen ions from the 73-inch Cyclotron and with 30-Mev oxygen ions from the Tandem Van de Graaff. Experiments included studies of angular distributions and excitation functions for transfer reactions, compound-nucleus reactions, effects of angular momentum on the density of nuclear states, and so-called Ericson fluctuations in the compound nucleus Si/sup 28/. Nuclear reactions induced with 22-Mev protons in the 86-Inch Cyclotron were used in studies of the pickup- reaction mechanism, shell-model studies from pickup reactions, scattering and the optical model, and level schemes in highly deformed nuclei. In theoretical investigations of the mechanisms of nuclear reactions and related nuclear- structure information, the elastic scattering of complex particles was analyzed via the optical model; the applicability of the distorted-wave method to stripping reactions was investigated, and the inelastic scattering of carbon ions from carbon was examined. Experimental studies with the eightsector electron model, Analogue II, led to very successful deflection of the beam in November 1962, a significant advance in accelerator technology, This investigation, still incomplete, eases one of the major uncertainties associated with the proposed Mc/ sup 2/ cyclotron. The radioactivity resulting from the residual undeflected beam being dumped onto …

This document lists the physics factors for the K Reactors following the transition to the KV fuel element geometry and zirconium tubes. Each new parameter with the zirconium tube lattice has been calculated relative to the factors used with aluminum tubes and the KIV fuel elements. The purpose of this document is to provide working values for plant assistance use during the transition to the zirconium lattice. In some cases, where there are large uncertainties in the absolute values, the conservative end of the range has been provided for present operational use in safety and control administration. Refinement and publication of ``best`` values for the zirconium lattice based on the extensive experimental and calculational studies are included in future Reactor Physics Unit programs.

Centrifugally cast stainless steel piping was selected for the primary piping of Spert III, a 2500-psi, 650 deg F water moderated and cooled nuclear reactor system, because of the significant cost advantage of using cast piping and because of favorable results from metallurgical examinations of the material. Essentially no operating experience was available at that time on the performance of cast piping in elevated pressure and temperature service. Presented are a brief history of operational experience with this piping in Spert III, the results of a recent plant inspection, and the results of the initial metallurgical examination of centrifugally cast material. On the basis of the Spert experience, it can be concluded that centrifugally cast stainless steel pipe has given adequate service under cyclic operation and probably is equal to high-pressure stainless steel piping fabricated by other methods. However, due to the limited general use of this material, no statement can be made as to the usual commercial quality of cast piping or to its performance under conditions other than those reported. (auth)

BS>The average energy required to form an ion pair, W, when alpha particles are absorbed in mixtures of argon with other gases is studied. The other gases were selected on the basis of their ionization potentials. One group consists of representative gases that have ionization potentials below that of Ar (15.77 ev) and above the doublet metastable state of Ar (11.49 and 11.66 ev). This list includes methane, carbon dioxide, nitrous oxide, xenon, and krypton. The other group of special interest consists of some gases with ionization potentials below the metastable state of Ar. All gases tested in these two groups cause an increase in ionization, i e., a decrease in W, when added to argon. As an illustration of this effect, the addition of 1/2% of acetylene to Ar will increase the ionization by 23% The experimental data, i.e., W as a function of relative concentration of the two gases, were fitted to a model in which it is assumed that energy is transferred from two excited levels in argon to the additive gases in collision processes. Good agreement between the experimental data and calculations based on the model is taken as additional evidence that the excited state notion …

The Zirflex and Sulfex processes for chemical decladding Zircaloy or stainless-steel-clad UO/sub 2/ power reactor fuels were successfully demonstrated at irradiation levels as high as 28,200 Mwd/t. The Zircaloy jackets were dissolved in boiling 6 M NH/sub 4/F-- 1 M NH/sub 4/NO/sub 3/, and the stainless steel jackets were dissolved in refluxing 4 M H/sub 2/SO/sub 4/. Both processes gave average soluble losses of uranium and plutonium to the decladding reagents of about 0.05%. Centrifugation or filtration of the highly radioactive decladding waste solutions was required to recover UO/sub 2/ fines produced by fracture of the UO/sub 2/. The fines were recycled and dissolved with the UO/sub 2/ cores in boiling 4 M HNO/sub 3/ solution. About 5 to 6 hr were required for complete dissolution of the UO/sub 2/ core to produce terminal concentrations of 100 g of uranium per liter and 3 M HNO/sub 3/. The core solution was a suitable solvent extraction feed after clarification and adjustment of plutonium valence with sodium nitrite. One cycle of the modified Purex process, in Mini mixersettlers, using 100-g-uranium-per-liter feed solutions, gave losses of uranium and plutonium to the raffinate of less than 0.1%, and gross gamma decontamination factors of about …

Dissolver solution samples were analyzed for neptunium, and the data are plotted as g Np/t U vs g Pu/t U.

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This report, from the Chemical Processing Department at HAPO for April 1963, discusses the following: Production operation; Purex and Redox operation; Finished products operation; maintenance; Financial operations, facilities engineering; research; employee relations; and weapons manufacturing operation.