None

Experiments were performed with 2.09% U/sup 235/-enriched uranium metal plates in a light-water-moderated and -reflected assembly. Each plate was 30 in. long, 31/8 in. wide, and 1/4 in. thick and contained 7.09 kg of uranium. In the first assemblies the plates were arranged in rows with edges adjacent, and the spacing between rows was varied from 5/8 to 1 1/8in. The optimum spacing was about 7/8 in. With the spacing between rows maintained at 7/8 in., the spacing between the edges of the plates was varied from 0 to 5/8 in. The optimum spacing between edges was 5/16 in. The minimum critical mass in these assemblies was 6.74 kg of U/sup 235/. (auth)

The effect of hot-worked thickness on the corrosion behavior of atmosphere-melted Zircaloy-2 is discussed. Hydrogen pickup upon etching Zircaloy- 2 Zircaloy-3, and properties of vacuum-cast Zircaloy-2 and the fabrication of special Zirccaloy shapes are presented. A hardness converison chart for annealed zirconium and zirconium alloys is included. (J.E.D.) The useful properties of the tungsten wires used in the incandescent lamp and ra dio tubes industry are ensured by adding about 1% of various ingredie (e.g., K, Na, Al, Si compounds) to the tungstic acid and producing metal powder and compressed rods. During the sintering of these rods, the additions are evapo rated to such an extact that finally the concentration of foreign atoms remains only 10/sup 5/. According to the investigations, the warm hardness values of these tungsten pieces is determined by the traces of impurities. In order to investigate the influencce of the various kinds of atoms, an apparatus was built for the determination of half-micro warm hardnesses of various kinds of tungsten metals in the temperature interval 20 to 800 deg C The tungsten wires made with additions containing Si had an average hardness H/sub V/ = 250 at 800 deg C, while the wires without such additions …

The effects of beams of protons and alpha particles from the 60-inch cyclotron and beams of accelerated nuclei of heliuan-4, carbon-12, oxygen-16, and neon-20 from the linear accelerator on thin films of dried enzymes were measured. The experimental apparatus is described and results are presented graphically. (C.H.)

Two problems are encountered in U/sup 233/b purification and metal production. One is high alpha activity, which requires that all operations be enclosed. The other is beta-gamma activity originating from U/sup 232/ present in U/sup 233/ as a contaminant. This, the immediate daughter of U/sup 232, produces a chain of strong beta-gamma emitters, which make shielding and thorium separation procedures necessary. Chemically impure solutions of metal fabrication residues are separated from trace amounts of thorium isotopes by cation resin exchange in shielded equipment. The short-lived thorium daugters are allowed to decay, after which beta-gamma activity is low enough to permit chemical purification in unshielded equipment. The U/sup 233/is chemically separated from nonradioactive contaminants by precipitation as UO/sub 4/- xH/sub 2/O, which is calcined to U/sub 3/O/sub 8/. The U/sub 3/O/sub 8/ is reduced to U0/sub 2/ and converted to UF/sub 4/. Pure metal is prepared by bomb reduction of the UF/sub 4/ with calcium as the reducing agent. Residues from the chemical purification steps, reduction, metal fabrication, and ganeral cleanup are processed into nitrate solutions, solvent extracted, and concentrated for recycle. Ion exchange, precipitation, reduction to metal, and casting all have effect upon the thorium isotopes and their daughters, resulting …

Experiments are described which studied the effect of irradiation upon small U/sup 235/ cylinders simulating in size those designed for thc initial CP-4 (EBR-I) fuel loading. Qualitative similarities between thermal cycling and irradiation effects were found, but none of the three types of inaterial tested were entirely dimensionally stable. (auth)

Experiments were performed to determine the critical parameters of aqueous solutions of 93.2% U/sup 235/-enriched uranyl fluoride contained in cylindrical annuli formed by various combinations of aluminum cylinders varying in diameter from 2 to 30 in. In all of the experiments the inside cylinder was lined with a 20-mil-thick cadmium sheet and filled with water to a height of 48 in., and in some experiments a water refiector was used on the sides and bottom of the outside cylinder. The data indicate that for the solution having an H:U/ sup 235/ atomic ratio of 50.4 the critical infinitely high reflected annulus would have a minimum thickness between 2.5 and 3 in., while the unreflected annulus would have a thickness between 3.75 and 4.5 in. The corresponding thicknesses for the solution having an H:U/sup 235/ atomic ratio of 309 would be between 3.5 and 4 in. for the refiected annulus and between 4.5 and 5.5 in. for the unreflected annulus. (auth)

The results of the hydrodynamic journal type bearing phase of the salt- lubricated bearing development program at Oak Ridge National Laboratory are given. One test each of two hydrodynamic journal type bearings constructed or INOR-8 versus INOR-8 was performed with molten salt #130 (62 LiF, 37BeF, 1 UF/sub 4/ mole %) at 1200 deg F as the lubricant. The first bearing operated for twenty minutes and the test was terminated due to seizure of the bearing and journal. The second bearing operated for 500 hours during which fifty-seven stopstart tests were performed and hydrodynamic lubrication was attained for extended periods at 1200 rpm and 200 lb radial load. Termination of the test was as scheduled at the completion of 500 hours of operation. Plans are also included for fur her testing. (auth)

The efficiencies and photofractions for monoenergetic garnma raps incident on sodium iodide (thallium activated) crystals have heen calculated by the Monte Carlo method. The calculations have been carried out for broad parallel-beam sources, point sources on the crystal axis, and disk sources, all for photon energies of 0.279, 0.861, 1.33, 2.82, and 4.45 Mev. The crystals considered were right circular cylinders with radii of radius, heights of 1.0, 2.0, 4.0, and 8.0 inches. The effect of the escape of annihilation gammas from the crystal was taken into account in the Monte Carlo calculation; however, no correction was made for escape of bremsstrahlung from secondary electrons and positrons. This latter correction is of importance only at the largest energies and for the smallest crystals where it affects the photofractions by a few per cent. (auth)

BS> Procedures are discussed for the utilization of a two dimensional diffusion theory computer program (QED) in the calculation of neutron flux peaking and control rod worths. Some typical results obtained for the first Yankee core are presented. Methods for reducing large problems to a size acceptable to the computer program are described. (auth)

Reactor control instrumentation systems may be subject to a variety of extraneous signals. Five types are discussed: signals involving high-frequency components which may gain access to critical circuits through wiring that lacks suitable RF filtering; current signnls due to mechanical shocking or flexing of cables; extraneous ion chamber signals, including displacement currents due to fluctuations in the polarizing voltage, as well as currents caused by mechanically induced changes in ion chamber capacity; signals whose origin is magnetic induction into cable loops; and signals involving magnetic induction and ohmic induction into auxiliary loops created by multiple ground connections. The emphasis is placed on magnetic induction and means of eliminating it. (auth)

Dissolution methods were developed to permit representative sampling of the slurry of corrosion and fission products collected by the HRT chemical process-ing plant. The procedure selected for HRT-CPP application was to use 15 ml of 10.8 M H/sub 2/SO/sub 4/ per gram of solids with agitation by boiling in a tantalum-lined dissolver. (auth)

The installation of a milling yellow flow visualization loop has been completed. Milling yellow is an organic dye which when dissolved in water exhibits flow double refracting properties that permit visual observations of flow patterns. The equipment is to be used in qualitative studies of flow patterns in various models of reactor vessels and components. (auth)

The technique described may be used to obtain data regarding the behavior of porous media when they are rapidly compressed. Data which can be obtained include relationships between stress and strain under dynamic conditions, coefficients of restitution, compression wave velocities, decay rates and wave form modifications. Although there is still room for improvement and refinement, the present technique can be used to produce data needed by, and not previously available to, designers of blast shields and similar structures. The data presented herein are preliminary, included mainly to illustrate the usefulness of the technique. It may be noted, however, that they leave little room for doubt regarding the value of porous materials in the absorption of shock energy. The coefficients of restitution are velocity ratios. Since the kinetic energy varies as the square of the velocity, between 90 per cent and 96 per cent of the initial kinetic energy was absorbed in the cases cited. (auth)

A series of calculations performed to determine the temperature coefficient of the Yankee first core is presented. The effect of control on the core coefficients is not included. (auth)

A theoretical treatment of the space- and timedependent flux oscillations in an annular seed-blanket reactor due to nonuniform formation and depletion of xenon is developed by a linearized treatment. The distinction between coupling within the seed and through the central blanket is brought out in the analysis. These results are compared to a four-point model of the seed blanket reactor. The unity of various methods of analysis is shown by the use of the concept of a xenon ''transfer function.'' (auth)

The nature of impurities found in reclaimed Pb and the effects of their inclusion in castings were investigated. It was concluded that impurities are difficult to remove and may result in unwanted casting characteristics. Recommendations for Pb reclamation are listed. (J.R.D.)

Data are given on the thermal ccnductivity of Ti--6 wt. % Al--4 wt.% V. The creep strength of 15% cold-worked Zircaloy-2 is being determined for reactor components in the 290 to 400 deg C range. Nine serles of high-strength corrosion- resistant Zr alloys were prepared and corrosion tested. Results are included. The fabrication of Al-U alloys for uses in various reactors is presented. The development of a natural-U fuel alloy with improved corrosion resistance is presented. Results of corrosion tests on the natural--U alloy are presented. A study is presented to investigate the possibilities of applying a thin protectlve coating of Mo on the interior surfaces of the reactor system by electroless and vapor-plating techniques. An irradiation-damage program to detcrmine the extent of damage to type 347 stainless steel in iast-neutron fluxes in the core of the ETR is presented. The properties of the high-niobium portion of the Nb-U constitution diagram are presented. The development of Th-U alloys with increased irradiation stability and corrosion resistance is presented. Dispersion-type fuel specimens containing 24 wt.% fully enriched UC and UN dispersed in a l8 wt.% Cr14 wt.% Ni-2.5 wt.% Mo--balance Fe matrix and clad with type 318 stainless steel were fabricated for …

Report discussing the results of an investigation to determine the low-speed power-off stability and control characteristics of a model of the Bell D-188A VTOL airplane. The static stability and control characteristics were generally satisfactory except above certain angles of attack and aileron effectiveness dropped off as the angle of attack was increased. Modifications for increasing the directional stability by altering the vertical tails are also described.

Several uncertainties associated with predicting activity levels in water-cooled reactors are discussed in connection with development of the Nuclear Merchant Ship Reactor (Maritime Pressurized Water Reactor). (T.R.H.)

Isotopes of hydrogen and oxygen may be useful in elucidating the mechanism of aqueous corrosion reactions, in which an important step may be diffusion of protons and/or hydroxyl for oxide) ions through a thin protective film. The technique of isotope exchange and the kinetic isotope effect both appear applicable. For the reaction between water and aluminum, the product (above 90 deg C) is alpha -alumina monohydrate ( alpha -AlCDH). The exchange of D/sub 2/O/sup 18/ with alpha -AlOOH (sub-micron crystallite size) was examined from 100 to 230 deg C. The rate of D-H exchange was appreciable: O/sup 18 / exchange was slow. The O/sup 18/ content of the separate phases suggested that only half the O atoms in alpha -AlOOH are exchangeable. Results were interpreted on the basis of a slow step involving independent diffusion of protons and oxygen carrier ions. The activation energy for the proton diffusion coefficient was ~ 12 kcal. The isotope exchange technique was applied to the reaction between water and aluminum at 100 deg C. Al (type 1100) sheets reacted with H/sub 2/O to the ''protective film'' stage, then with D/sub 2/O. The D content of the film increased, but the net exchange (corrected for …

A survey of recent publications concerned with structural and mechanical aspects of nuclear reactor containment was conducted during the first phase period. This report presents an annotated bibliography of 279 such publications. Many of the references listed appeared in Nuclear Science Abstracts and were published in the period from 1954 through 1957. (auth)

Compressibility factors and fugacity coefficients for hydrogen, niftrogen, oxygen, carbon dioxide, ammonia, methane, and helium were calculated by use of the Beattie-Bridgeman equation of state. The results are tabulated for various pressures up to several hundred atmospheres, and temperatures up to several hundred degrees, at sufficiently close intervals to allow for easy interpolation. A comparison is made of the calculated compressibility factors with the experimental values over those ranges of temperatures and pressure where the latter are available. From this comparison an attempt is made to indicate the probable reliability of the fugacity coefficients by the number of significant figures shown. (auth)

A set of 55 experiments hss been outiined to provide a minimum irradiation program for selection of UO/sub 2/, pellet geometry and fabricntion techniques, and canning technology. These experiments fall into three catagories: prototype: untts in which radial dimension and heat fluxes sre close to proposed design values, but irradiation times are long; reduced-size prototype for accelerated tests in which most variables will be studied; and miniaurized pellet irradiation to obtain high burnup for fission gas release studies. Reactor space has been found generally available and several installations are now examining their capabilities to participate in the program. A tentative schedule has been drawn to illustrate the feasibility of the program. (auth)