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)

An over-all description of the background material on the use of electrical arcs for heating of powders is presented as well as a summary of experimental studies on the arc calcination of thoria. Favorable results have been indicated both with heating thoria powder in an arc heated gas and with thoria formed into a consumable electrode. Use of a consumable electrode produces thoria particles 0.1 to 0.01 mu in diameter. It is recommended that additional electrodes be fabricated and further arc calcination tests be run to produce a quantity of product sufficient for evaluation. (auth)

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.

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.

Data are presented from the following studies: the radiation chemistry of pepsin, gelatin, methanol, benzene, and hexanes; the effects of irradiation of the pituitary in advanced cancer using high-energy particles from the 184-inch cyclotron; applications of ion beams in biological studies; the metabolism of strontium-90 and its relation to calcium metabolism in rats; hematological effects of low-level radiation doses in man; the influence of diet on serum lipoproteins; development of simplified methods for the analysis of blood serum for lipid content; tracer studies employing iron59 of red blood cell production and destruction and iron metabolism in a wide variety of blood disorders; tracer studies on heart function and blood circulation employing I/sup 131/; applications of C/sup 14/ in studies of leukocyte formation from which it was concluded that peripheral neutrophils have a 2-day life span, large lyphocytes a life span of 2 to 3 days, and small lyphocytes a life span of between 8 and 14 days; tracer studies employing P/sup 32/ in studies of the phagocytic action of cells of the reticuloendothelial system; factors regulating the volume of the body fluids; and development of a method for determining estrogen concentration in urine. Radiation protection activities are summarized. Lists are …

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)

None

The measured diffusivity of uranyl nitrate in water at 25 ction prod- C was 0.7 x 10/sup -6/ cm/sup 2//sec with about 40% average deviation. A program was started to develop nonnuclear uses for depleted uranium. Two continuous DRUHM reaction runs were terminated due to erratic operation of the sodium metering system. In the second Fluorox run with crude UF/sub 4/ which lasted for 29 hr, a total material balance of 94.8% was obtained and 17.9% of the theoretical amount of UF/sub 6/ was collected in cold traps and chemical traps. Room temperature flow rate-pressure drop calibrations of a multiclone (thirteen 0.60-in. diam hydroclones in parallel) for installation with the HRT replacement circulating pump were completed. Mixed oxides of U : Th = 0.08 : 1 and all have low yield stresses of 0.02 to 0.05 lb/sq ft compared to 0.2 to 1.0 lb/sq ft for normal Th-U or Th oxides of 1.5 to 2.5 micron mean diameter. The rates of uranium anion exchange from solutions containing between 0.025 and 0.20 M sulfate were measured and apparent uranium diffusion coefficients between 1.2 x 10/sup -7/ cm/sup 2//sec and 1.6 x 10/sup -7/ cm/sup 2//sec were calculated. In bench scale studies, …

None

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)

None

The intent of this study is to establish more completely the justifications for constructing a decontamination plant as outlined in Budget Item B 5720, ``Containmented Equipment Renovation Shop,`` FY 1957, Plant and Equipment Projects. In particular, the economic incentives have been explored. The question or idea has been investigated of assigning a dollar value to engineering information which might be obtained from examining contaminated equipment which has failed from unknown causes. Heretofore it has not been possible to examine such equipment because suitable decontamination facilities have not been available. An effort has been made to uncover all possible uses for the proposed facility in order that the estimated capital and operating costs might be evaluated in terms of all the functions which the proposed plant might perform.

None

A major problem in the development of a pressurized water reactor coolant system for the NPS is the rupture performance of the fuel elements. As water temperatures are increased to 300 C, uranium corrosion rates increase rapidly. Swelling of the uranium fuel by corrosion could cause the process tube to burst or reduce the tube cooling water flow below acceptable limits. The desirability of slow cooling of the water to avoid thermal shocks to the reactor piping after a rupture is detected further complicates discharge and decontamination problems as fuel will continue to corrode with attendant fuel element damage during the cooling period. Coextruded uranium-zircaloy-2 clad fuel elements are scheduled for use in the NPR. The rupture behavior of this type fuel material after heat treatment was studied in ELMO-4, an out-of-reactor recirculating water loop. Several types of initial defects were studied. Fuel materials with five different heat treatment histories and with different types of defects were tested to determine their rupture behaviors. The five conditions were (1) as-extruded material as received from Nuclear Metals, Inc., (2) beta heat-treated and water quenched, (3) beta heat-treated and air-cooled, (4) beta heat-treated, isothermally treated at 600 C and air-cooled, and (5) beta …

None

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

The development of a remotely operated device for determining the coalescence times of plant process streams suspected of containing surfactants such as silicic compounds and fission product zirconium compounds is described. A general correlation between the coalescence times of pilot plant extraction column aluminum nitrate feeds and 3.25 percent tributyl phosphate extractant streams and the observations of column behavior of these streams is demonstrated. The application of the coalescence test to plant streams is given. (auth)

None

Diffusion coefficients for hydrogen in beta zirconium were determined from permeation rates in the range 650 to 850 deg C. Both the steady-state method, which is dependent upon the hydrogen concentration, and the time-lag method, which is independent of hydrogen concentration, were employed to obtain diffusion data. Zirconium disks, 0.03 to 0.1 cm thick and varying in hydrogen concentration from 9 to 33 at.%, were used to measure permeation rates. The diffusion coefficients determined by the steady-state and time-lag methods on samples of differing thickness were in agreement. It was concluded that the permeation process was diffusion controlled. The diffusion coefficients were found to be independent of concentration and can be expressed by D = 6.14 x 10/ sup 4/ exp (--45,900/RT). (auth)

Nuclear power cost is plotted versus thermal efficiency. The relationship is not limited to any particular reactor type and is applicable for any reactor system where steam is the working fiuid for the turbogenerator. (T- R.H-)

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)

None

None