This report concerns the continuing problem of providing waste tank designs which will insure safe storage of radioactive waste over long periods of time. These tanks must withstand severe stresses imposed by earth loading, by hydrostatic pressure and by temperature gradients. The temperature gradients are caused by contained in the waste. The waste entering the tank is relatively cold, but the temperature rises rather rapidly to the boiling point as filling proceeds and then the temperature continues to rise as self-concentration increases the boiling point of the waste. The temperature gradients are therefore transient in character and they may be calculated only by rather tedious and complex methods; however, the gradients must be established in order to provide design data for structural design purposes. This report describes the methods used to calculate the temperature gradients and presents the calculated results for a particular tank design used under various operating conditions.

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The benefits of the poison spline system as developed and partially tested by the Facilities Engineering Operation are considered over a two year period. The full pile operational charge-discharge installation at the end of that time could make the poison spline system a marginal operation. This document list the production gains that are possible, how these gains compare with the cost of the poison spline system, and how this system compares with other available supplementary reactivity control systems.

Laboratory scale experiments with synthetic Purex 1WW and HAW have demonstrated the feasibility of recovering cesium by precipitation with metal ferrocyanides and ferricyanides. One method for recovery of cesium involves neutralization of the precipitate ferric hydroxide and sodium diuranate, and recovery of cesium from the supernate by precipitation with zinc ferrocyanide. Another method involves precipitation with nickel or ferric ferrocyanide from partially neutralized 1WW, or from HAW. The second method yields a voluminous precipitate with low specific activity and poor radiochemical purity of the cesium, thus necessitating further purification and concentration of cesium before packaging. This can be accomplished by metathesis of the precipitate with sodium hydroxide and precipitation of cesium with zinc ferrocyanide. Other methods for recovery the cesium from metal ferrocyanides have been investigated by other workers. Several of the more attractive cesium recovery flowsheets have been demonstrated with synthetic solutions on the laboratory scale. To demonstrate the feasibility of cesium recovery from plant solutions, the effects of radiation and trace chemicals (such as corrosion products, fission products, and impurities in uranium and process reagents) must be determined. Therefore, the present work was performed with full-level Purex waste solutions, both 1WW and HAW.

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A method has been developed for the uniform coating of graphite tubes with carbides of niobium, tantalum, and zirconinm by thermal decomposition of their respective halide vapors. Conditions of coating temperature and pressure are so chosen as to prevent the deposition of metal, but to permit the formation of the carbide as rapidly as carbon can diffuse to the surface. If the carbon diffusion can be made the rate-limiting step, the coating process becomes self- regulating and uniform thickness results. The limits of the temperature-pressure range have been determined experimentally for the thermal decomposition of zirconium iodide and of the chlorides and bromides of niobium, tantalum, and zirconium. With the successful development of coating equipment and definition of conditions, 99 blowpope test specimens were coated with uniform, continuous, and adherent layers of the carbides in three ranges of thickness, light (0.001 in.), medium (0.005 in.), and heavy (0.01 in.). Determinatlons were made of the coefficient for the diffusion of carbon in zirconium carbide as a function of temperature. Exploratory work on small specimens of graphite impregnated with 7 wt.% uranium indicated that the coating results were essentially unchanged, but that loss of uranium occurred. Means of avoiding the loss of …

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BSR Loading 33 consists of an essentially 5 by 6 fuel element array completely reflected by water. It was controlled by means of two boron carbide shim-safety rods and a type 347 stainless steel regulating rod with an 57-mil wall, located as shown in Fig. a. The critical mass was about 3.4 kg of U/sup 235/ , with an excess reactivity for the clean cold loading of about 0.6%. The total mass in the initial loading was 3.6 kg of U/sup 235/. Loading 33 was initially assembled in November 1954, from clean cold fuel elements. The power calibration was made during the first series of runs at power levels appreciably above 1 watt. Cobalt foils were used as the detector material for the thermal neutron flux determination in the lattice. The foils were exposed at 6-in. intervals in vertical traverses in the water passage between the last two plates on the outside of the fuel elements. Measurements were also mnde along the vertical axis of the element in lattice position 25, which was approximately at the center of the configuration. Cadmium ratios were determined at centerline and at 6in. intervals below centerline. Symmetrical flux distribution was assumed around the north-south …

The Bevatron uses a system of electrodes through which the internal proton beam passes in order to continuously measure the magnitude and radial position of the beam. The bunched circulating beam induces a periodic voltage on the electrodes. This signal is amplified and displayed on an oscilloscope and also converted to direct current for operation of a recorder. Two types of electrode systems are used. The first is a large hollow box to provide beam magnitude signals for specialized monitoring and for primary calibration. The second system consists of two sets of smaller electrodes. One set provides beam radial-position information for tracking control, and the other provides beam magnitude information for magnitude control and for general distribution to experimenters associated with the Bevatron. A telemetering radio link is used to relay beam information to those in other areas. Problems associated with handling the beam signal are discussed, and the design principles involved in detection, amplification, and isolation of the signal are described. Calibration techniques, signal distribution facilities, and control features are also given. The systems described are stable and provide the desired information with a minimum of maintenance and operational difficulty. (auth)

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Lecture presented at the Atomic Industrial Forum's Third Course on Reactor Materials, Stanford University, Stanford, California, July 9-19, 1957A review of progress in the use of liquid metals is presented. A number of liquid metals are compared, and the general problems of selecting container materials are considered. In addition. a discussion of corrosion mechanisms and corrosion testing methods commonly employed are examined as well as problems encountered with the liquid metals of greatest interest. (J.R.D.)

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Photoinduced electron spin resonance signals have been observed in isolated chloroplasts and other green materials with a growth time not affected by reducing the temperature to -140 deg. This is interpreted in terms of conduction-band and trapped-electron theory.

Transformation kinetics of binary U -Nb and ternary U-Nb-base alloys were investigated. Additions included zirconium, chromium, titanium, silicon, nickel, nnthenium, and vanadium. Encapsulated samples were given a homogenizstion anneal at 1000 or 1100/sup o/C, water-quenched from 906/sup o/C to retain the phase, and reheated to temperatures between 360 and 600/sup o/C. The metastability of the phase was examined by metallographic, hardness, resistometric, dilatometric and x-ray-diffraction techniques. The U -Nb system is characterized by a monotectoid decomposition of the high temperature allotrope at about 645/sup o/C to form alpha and /sub 2/, a niobium-rich cubic structure. Decomposition in U-Nb and in most U-Nb-X alloys occurred by a continuous precipithtion of alpha from the body-centered cubic phase with a resultant enrichment in niobium of until the equilibrium /sub 2/ composition was reached. In the U-Nb-Ti and U-Nb-V systems, alpha and /sub 2/ were coprecipitated. Annealing at 550 and 600/sup o/C produced decomposition products which, in most materials, originated at the grain boundaries; a fine precipitate which initiated throughout the matrix was observed at lower annealing temperatures. Increasing the niobium content resulted in greatly increased stability. The following elements added to a U-Nb base were found to retard transformation of the phase: zirconium, …

A system for concentrating uranyl nitrate solutions was designed and installed in the Thorex Pilot Plant. A total of 16,060 g of uranium was concentrated in the system in 68 batch runs. A total of 14,400 g total uranium (14.180 g U/sup 233/) was recovered as product suitable for shipment. Uranium loss to the evaporator condensate was 0.03% of ihe total uranium processed. The material balance across the system was 98.4%. The average concentration of uranium in the evaporator feed solution was 29 g/liter; the average concentration in the evaporated solution was 298 g U/liter and in the product solution was 199 g/liter. Radiation readings of bottles containing product solutions were taken with a hard-shell cutie pie immediately after each run, and these readings ranged from 35 to 1100 mr/hr. The radiation levels of the bottles of product solution shipped averaged 78 mr/hr. Bottles of product solution reading in excess of 300 mr/hr, maximum allowable for shipment. were reprocessed in the second-cycle solvent extraction system (Thorex) and reconcentrated. The products from seven runs had radiation levels in excess of 300 mr/hr at the time of concentration, or the activities had grown to that level by the time of shipment. The …

Fission yields were determined from 14-Mev neutrons on U/sup 235/ and U/ sup 238/, thermal neutrons on U/sup 235/, and fission spectrum neutrons on U/sup 235/, U/sup 238/, and Pu/sup 239/. The number of fissions was determined for the Mo/sup 99/ activity. The Sr/sup 90/ was chemically separated and Y/sup 90/ allowed to reach equilibrium. The Y/sup 90/ was separated and counted. (W.D.M.)

The Nevada Test Site (NTS) Use Committee met Tuesday morning, May 28, 1957, at Mercury, Nevada. This document provides a summary of the meeting.