EWR-ESE-144, Fifty MC-890 type final assemblies were subjected to irradiation at low temperature test in order to determine if irradiation would reduce the frequency of high voltage breakdowns. A control lot of a like number of units was subjected to low temperature test in the same manner except without irradiation.

Design features and operating characteristies of the Los Alamos Power Reactor Experiment No. II are discusssd. Results of performance tests and of an examination conducted after disassembly of the reactor are presented. Recommendations for work on uranium phosphate fueled reactors are made. (auth)

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A combination densitomer and analog computer is described which determines radiation exposure of photographic film used in personnel badges. The range of the instrument is 0to 300 mr gamma and 0 to 300 mrad BETA plus gamma . A novel phototube circuit is used to obtain logarithms directly. (auth)

This report discuss the design of the Plutonium Reclamation Facility the capacity of which will be 300 kilograms per month or 3600 kilograms per year or plutonium. The subject facility, as the name implies, must be extremely flexible in its ability to handle a wide variety of feed materials. The new facility will be operating on a three-shift day, five-day week, 40-week year with an overall efficiency of 75 percent; twelve weeks per year will be required for ``turnaround`` time to enable campaign operation for segregation of feed plutonium by isotopic content.

Lengths of pistillate inflorescences of sedges (Carex spp.) growing in the contaminated soils of White Oak Lake bed were measured in relation to radiation fields. Carex Frankii Kunth and Carex vulpinoidea Michx. populations were sampled from areas with air dose rates of 0, 10, 20, and 40 mr/hr. Analyses of variance showed that mean lengths of inflorescences of C. vulpinoidea were simllar to each other in these areas but that those of C. Frankii were significantly different. However, the sites differ in such factors as soil moisture, fertility, and alkalinity, so that these differences in the length of inflorescence may not be accounted for primarily by the exposure dose rate of the radiation field. (auth)

An attempt is made to ascertain the optimum working conditions of a pile oscillator and to compare this method with the danger coefficient technique from the point of view of minimum amount of resonance absorption which can be detected. The space-time behavior of the absorption properties of the sample is described by means of a delta -function and the reactor kinetic equations are obtained by using a single mode expansion of the flux. The results are applied to a bare reactor model equivalent to the fully reflected, parallelepiped BSR-I. (W.D.M.)

This document details activities of the chemical processing department as compiled by the operation managers during the month of March, 1960.

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Potential cladding materials for a flat-plate fuel element containing a dispersion of UC or UC/sub 2/ in U--15 wt.% Mo alloy were surveyed on the bases of compatibility with the fissile compounds, matrix material, protective cover materials, and liquid sodium as well as the feasibility of fabricating fuel plates by roll cladding. Radiative-capture cross sections, thermodynamic data, eutectic and intermediate compound formation, mechanical properties, and corrosion by 1000 tained F Na are reported for austenitic stainless steels, chromium, nickel, niobium, molybdenum, tantalum, vanadium, and zirconium. It was recommended that "A" nickel (molybdenum barrier), Zr-3 wt.% Al. Nb--2 wt.% Cr, and Fansteel 82 be relected for investigation. (auth)

A paper computer is presented for finding the fourth from three known variables: upper confidence limit, confidence level, number of observations, and number of events with a specified characteristic. Complete instructions for computer operation are given. (D.L.C.)

An investigation was conducted to determine the effects of He leakage through EGCR moderator columns and fuel element sleeves on the core coolant flow distribution reported in study II-179-1. Results of the investigation are discussed and recommendations for design changes so that the total coolant bypass will remain the same as previously reported are made. (J.R.D.)

Corrosion specimens of the five major aluminum alloys used in the construction of the Oak Ridge Research Reactor have been exposed to the high- purity primary cooling water in the ORR core and in the extennal portion of the primary cooling loop to determine their corrosion rates under actual operating conditions. These alloys, 1100, 3003, 5052, 5154. and 8061, exhibited average corrosion rates of less than 2.6 mpy during the first 500-hr test period and less than 0.5 mpy for a 4032-hr test. Very superficial pitting was observed. and no case of intergranular corrosion was found. (auth)

The data consists of out and inlet temperatures, and panellit and header pressures, sorted according to date and tube-pile.

plate and to calculate its critical dimensions. Calculations were made which show that the plate and positioning keys meet the design requirements. Work sheets pertaining to the evaluation are included along with references to drawings. (J.R.D.)

The intent of this document is to establish criteria for equipment for: Receiving, handling and component inspection; miscellaneous handling and storage; final inspection; and finished storage in the new fuel cladding facility.

A survey was made of sealing methods and their adaptability to the requirements of the plenum reflector seal on the HTGR reactor vessel. A leak rate through the seal of 43.8 pounds per hour of helium was established as an acceptable leak. Lap joints of steel to graphite or graphite to graphite with a 100 RMS surface finish met the required leak rate and two basic concepts of this type of seal are illustrated. (auth)

The design approach followed in this study is that of handling and processing plutonium solution and powders within tightly sealed but readily replaceable units of processing equipment, each one of which will do one step in the overall process. The presently used method is to use open equipment enclosed in glove boxes attached to a transporting device. Elimination of the glove box enclose and its replacement by tightly sealed and detachable equipment provides the accessability necessary for equipment repair and reduction of down time, thereby reducing costs. Most of the primary functions for the entire button line have been studied and no insurmountable design problems have been encountered. Studies of the pre-reduction and filtrate treatment functions and the PR can unloading and RC can loading equipment have been summed up and compiled into a design criteria. Design concepts for all of the equipment for processing from the nitrate through the button stage have been worked out and appear to be acceptable approaches, except for the vacuum drum filter and the vibrating tube reactor. The latter two components have been studied and drawings prepared; however, the concepts developed are not considered entirely acceptable from the operation and maintenance standpoint. Because of …

Chemical decladding of stainless-steel- and Zircaloyjacketed fuel elements is discussed relative to cladding activation and waste-disposal cost as compared with a total dissolution process. (C.J.G.)

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A multiple casting process was developed for the production of 0.590 plus or minus 0.005-in. diam. by 12-in. long solid right cylinders. The process involves vacuum induction melting in MgZrO/sub 3/ coated graphite crucibles and casting into coated graphite molds. Thirty-eight hundred fifty 90 wt.% U of 1.5 wt.% enrichment-10 wt.% Mo as-cast pins were produced for HNPF Exponential Experiments. (auth)

The release of fission products from porous fuel elements during irradiation may be largely a diffusion process. An equivalent-sphere hypothesis was proposed to provide a model by which the diffusion can be analyzed. The equations of diffusion were previously solved for in- pile conditions. The slow convergence of the formulas makes the previous solutions awkward. In the present investigation alternate formulas were derived which are more suitable under certain circumstances. Tables were prepared from which release rates and accumulations may be evaluated for prescribed conditions. The application of the analysis to the interpretation of release data is explained. (auth)

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