Some calculations have been made to estimate the characteristics of a neutron-burst type fast reactor similar to Godiva but made up of relatively small component parts--the so-called "layered assembly." One spherical and three cylindrical assemblies have been considered. Critical masses, assuming 5% voids, range from 58 to 65 kg of 93.4% enriched U/sup 235/. For a reactivity addition of 0.33 dollars above prompt criticals bursts between 2 x 10/sup 17/ and 6.7 x 10/ sup 17/ fissions were computed with accompanying temperature rises varying from 514 to 1600 deg C. The burst width at half-maximum was about 12 microseconds. To obtain an idea of the possibilities of stress reduction which might be achieved by layerings an assembly made of small rings was considered. While the critical masses obtained here are believed to be fairly accurates the predictions concerning mechanical energy generated, total fissions, and burst width may be subject to sizeable error due to the many simplitications required to allow hand computations. Neverthelesss considerable improvement in safety and burst-size is indicated by the use of a "layered assembly" instead of an assembly composed of relatively thick parts. (auth)

The purpose of this procedure is to present a detailed, chronological presentation of the preliminary decontamination and post decontamination steps necessary to fulfill the requirements of the Production Test Authorization IP-239-N. The procedure attempts to present the required operation in sufficient detail to successfully accomplish the intent of the test. Certain procedures involve operations of a standard nature and have not been elaborated upon to any great extent, as it is expected that the reactor operations and radiation monitoring personnel will implement these instructions according to standard operating procedures.

Nuclear safety in the dissolution of irradiated 0.95 U235 enriched fuel has been investigated. In particular, critical conditions of fuel of this enrichment in a 52-inch diameter dissolver crib were studied. Since a crib this size is not safe by geometry, dissolution procedures as well as maximum safe batch sizes were analyzed. Uranium-water lattices are normally studied in systems in which rods are uniformly dispersed in the moderator. The results of such a study for 1.34-inch diameter solid rods as well as I. and E. fuel having a 1.37-inch O.D. by a 0.48-inch I.D. have already reported.

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Will Wilson, regarding a legal question submitted for clarification: Whether the Secretary of State can accept and file an application for a Certificate of Authority under the provisions of Article 1513a of Vernon's Civil Statutes for a purpose which is not identical in language and does not include the entire purpose clause authorized by said statute.

Annual report submitted by the Boy Scouts of America to Congress describing highlights from , activities, organizational leadership, and other information about scouting programs.

In order to establish the feasibility of using two colorimetric met;iods for the determination of uranium interchangeably, according to the interferences encountered in a particular sampte. results were obtained by each of the methods and compared. The dibenzoyl methane method and the ethyl acetate-ammonium thiocyanate procedure were compared on the basis of values secured on the same day. on different days, on an analysis of the variance. and on an analysis of the residual error for the methods on different days. On the basis of the findings of these tests. it is concluded that the two methods can be used interchangeably to determine the uranium content of the ethyl acetate extracts of samples. Since the interferences in the two methods are different. the uranium content of a variety of materials can be determined without additional separations being required. (auth)

Data on the effects of nuclear fuel burnup on dissolution rates and U losses of a few fuel types are summarized. Burnup to the 40% level produced very little effect on the rate of solution of stainless steel-UO/sub 2/ fuel elements in solutions of the Darex type. Beyond passivation, burnup to the 250 Mwd/T level did not produce a large effect on the rate of decladding nor on the U losses in the Sulfex process. Bunnup to the 15% or 4300 Mwd/T level produced little or no effect on the rate of decladding, U losses, or Pu losses in the Zirflex process. Two other effects, air oxidation of irradiated UO/sub 2/ and prolonged contact of this oxide with Sulfex solutions in the absence of actively dissolving stainless steel appeared to be much more serious sources of loss of U. (auth)

Liquid Metal Fuel Reactor Experiment program annual technical report.

Annual report of the Liquid Metal Fuel Reactor Experiment describing progress during calendar year 1958 and as well as an evaluation of progress and plans for future work.

The in-line monitoring instruments installed in the Redox plant in the late 1950s consisted of six gamma monitors, a single channel gamma spectrometer, an alpha monitor, and a neutron counter. A gamma monitor on the steam condensate outlet line and a uranium monitor on the 2DFS stream were to be added at a later date. The first section of this information manual describes the in-line gamma monitors and gives operating instructions for them. The second section covers the alpha monitor, and the third section the neutron counter. Sections on the uranium monitor and the steam header gamma monitor were to be added at a later date.

Progress made in the field of spectrophotometry of molten fluoride salts is summarized. The high-temperature cell assembly designed and fabricated for use in this work is described, as well as the various types of sample containers used. Spectra of nickel fluoride, cobalt fluoride, chromic fluoride, and uranium tetrafluoride in LiF--NaF-KF (46.5-11.5--42 mole%) are presented. (auth)

Introduction: Seldom does the actual arrangement of control elements in a nuclear reactor confers to the ideal and convenient mathematical array. In order to achieve shim control. safety and regulation, it is desirable to design with rods of different sizes and materials. With given fuel element arrangement, typically in square or hexagonal lattice spacing, there will be rods located at different distances form the center of the core and from each other. As the reactor operates, absorbers will be withdrawn, leaving further asymmetries in the location of those remaining. It is the purpose of this report to develop in detail a two-group diffusion theory with as complete generality as possible. The method is as yet restricted to the unreflected core, or to the reflected core by use of reflector savings and bare equivalent geometries.

Abstract: This monthly progress report covers the activities of the Army Gas-Cooled Reactor System Program for April 1959. The program includes a water-moderated heterogeneous reactor (Gas-Cooled Reactor Experiment I), a graphite-moderated homogeneous reactor (Gas-Cooled Reactor Experiment II), a mobile gas-cooled reactor (ML-1), and the coordination of the Gas Turbine Test Facility. [It reports] the progress of each project, the associated tests and data evaluation, the applicable design criteria, and the fabrication of reactor components" (p. 1).

The Army Gas Cooled Reactor System Program includes water moderated heterogeneous reactor (Gas Cooled Reactor Experiment I), a graphite moderated homogeneous reactor (Gas Cooled Reactor Experiment II), a mobile gas cooled reactor (ML-1), and the co ordination of thc Gas Turbine Test Facility. The progress of each project, the associated tests and data evaluation, the applicabie design criteria, and the fabrication of reactor components are briefly summarized. (For preceding period see IDO-28538.) (W.D.M.)

In early July 1958, it appeared that Columbia River temperatures at HAPO would be near 24--50{degree}C by the end of August. River temperatures were averaging 40 to 50{degree}C above 1957 figures and were 3{degree} to 4{degree} above the ten year highs. It seemed desirable to examine the problem to determine if any corrective measure could be taken, since it was apparent that production losses were imminent. The large storage of cold water behind Grand Coulee Dam, normally untapped, was a source of possible relief. A plan for use was proposed for the peak high temperature period and agreed to by the Bureau of Reclamation.

In early July, 1958, it appeared that Columbia River temperature at HAPO would be near 24.5ºC by the end of August. River temperature were averaging 4º to 5º above 1957 figures and were 3º to 4º above the ten year highs. It seemed desirable to examine the problem to determine if any corrective measure could be taken, since it was apparent that production losses were imminent.

The temperatures of the Columbia River was reduced 1 to 30 Centigrade with beneficial effects at HAPO. It is reasonable to expect that future benefits may be possible. It is desirable that the temperature of the river be controlled each year to the maximum extent possible. Instrumentation improvements requested to effect optimum savings. Records of river temperatures and flows should continue to be maintained by IPD as a necessary part of temperature optimization. Where possible, the coincident use of the river cooling technique should be made for the benefit of anadromous fish.

The design of internally cooled electrical coils for the production of high intensity magnetic fields presents many new aspects and combinations of the familiar modes of heat transfer. However, the customary methodology appears to be sufficient for preliminary analysis and understanding of those problems. This methodology comprises the derivation of a qualitative, approximate equation expressing the relative performance of the various parts of a system, followed by an examination of this equation in order to locate the limiting features of the system. These features are then investigated by more powerful methods, which in turn provide guidance for development research in the laboratory. (auth)

The design of internally cooled electrical coils for the production of high frequency intensity magnetic fields presents many new aspects and combinations of the familiar modes of heat transfer. However, the customary methodology appears to be sufficient for preliminary analysis and understanding of those problems. This methodology comprises the derivation of a qualitative, approximate equation expressing the relative performance of the various parts of a system, followed by an examination of this equation in order to locate the limiting features of the system. These features are then investigated by more powerful methods, which in turn provide guidance for development research in the laboratory.

An elementary discussion is given of the reactor parameters which determine the signal-to-noise ratio obtainable with a pile oscillator. (auth)

In the use of a reactor as a device to measure neutron cross sections, the pile oscillator is often employed because of its much higher sensitivity compared to that available in static reactivity measurements. The factor limiting the available in static reactivity measurements. The factor limiting the available sensitivity is the generation of random noise, which originates in the statistical nature of the chain reaction. In other words, the nuclear reactions which maintain the chain reaction do not proceed uniformly, but rather at rates which fluctuate in time around some average values. These fluctuations limit the accuracy of measurements in the reactor.

This document details activities of the Fuels Preparation Department during the month of April 1959. (FI)

Hastelloy F is a prime contender as a material of construction for plant dissolvers in the power fuel reprocessing program. Consequently, the fabrication and installation of dissolver was undertaken to delineate any unknown problems associated with the use of Hastelloy F; and, at the same time, to provide a vessel for development studies on the Niflex or the Sulfex processes. The purpose of this report is to describe the actual basis for design as well as to present the problems encountered during the fabrication of the vessels.

In considering the problems associated with the measurement of SSNM content of Non-Production Fuels, two distinct problems are apparent. The first is the technical problem of obtaining highly accurate measurements in a complicated chemical and physical system. The second is the administrative problem of choosing a measurement system which provides a basic of financial settlement acceptable to both the seller (reactor operator) and the buyer (Commission).