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A preliminary investigation was made of techniques and materials for canning graphite to protect it for use at high temperatures in a nitrogen--oxygen atmosphere. Fabrication techniques for cladding bare and copper--plated graphite cores either in Type 316 stainless steel or Inconel X were developed. Specimens of the various combinations of core and cladding materials were subjected to simulatedservice conditions and evaluated. In all cases the Type 316 stainless steel-clad specimens failed by carburization and subsequent oxidation in relatively short periods of time. Although considerable trouble was experienced with rupture in the vicinity of the cladding welds during thermal cycling of the Inconel X-clad specimens, this material appeared to be satisfactory in other respects and is considered promising. A specimen of silicon-coated graphite eiad with Type 316 stainless steel was tested by heat treating for 624 hr at 1800 deg F. The silicon coating alloyed with the cladding material, formed a high-silicon diifusion zone, but prevented carburization of the stainless steel. (auth)

A report is presented to provide a tool for evaluating the relative economic incentives for changing reactor core parameters. The cost relations are shown in terms of differential cost in lieu of total cost. A total cost for each reactor described is included so that power costs for a specified set of parameters can be obtained. A description is also included concerning 5 reactor types considered along with a discussion of the effects on power costs of varying the significant core parameters. A listing of basic references is given. (J.R.D.)

A brief discussion of the core charteristics of four uranium fuel, pressurized-water type: Army Package Power Reactors, the SM-1, SM-1A, PM-2A, and SW-2, is presented. The characteristics discussed are cell geometry, fuel plates, core geometry, flux distributions, core loading, core burnout, and control reds. Tables and illustrations are included. (auth)

A description is given of a code for the IBM-704 computer which reduces and fits by least squares the measurements of radioactivity of a sequence of foils. Corrections for background, counter deadtime, foil weight, and radioactive decay are applied, and readings outside a specified range are rejected. Errors due to statistical fluctuations are computed and off-center ordinates are calculated. Reduced data are then fitted by least squares to the best value of the arguments of Bessel J/sub o/ or cosine functions. Up to 100 foils in a sequence can be handled, and decay times up to 999 min can be accommodated. An IBM-704 computer having 8192 words of core storage is required. No drums or tapes are needed. Running time for a typical 50 point problem involving data reduction alone is 2 min. With least squares fitting, the same problem would require 4 min. (auth)

Procedures are described for both a titrimetric and a gravimetric determination of hafnium in aluminum -hafnium alloys. The gravimetric procedure is used if the hafnium is to be recovered; otherwise, the titrimetric procedure is preferred. The sample is dissolved in aqua regia. Any undissolved hafnium is taken into solution via pyrosulfate fusion. The hafnium is separated from the aluminum and contaminants in the aluminum by precipitation as the mandelate. In the gravimetric procedure the hafnium mandelate is heated to the oxide, then weighed. In the titrimetric procedure the mandelate is destroyed with nitric, sulfuric, and perchloric acids. The hafuium then is determined by adding a measured excess of EDTA and back titrating the excess EDTA with a standard bismuth solution to a xylenol orange end point. (auth)

The development of microstructural detail by cathodic bombardment has been used successfully for many metals and alloys which are difficult to etch by conventional methods. An application of this technique to plutonitun and its alloys is presented. A method for preventing the specimen from overheating is included in the description of the equipment. Photomicrographs of a few clean, well defined microstructures obtained by cathodic bombardment of plutonium and some of its alloys are also are included, together with photomicrographs of the same specimens etched by means of conventional techniques. (auth)

An IBM-704 thermal transient analysis code, designated F0020 was developed to reduce transient test data for a single vertical, rectangular coolant channel. Modes of heat transfer to water at 2000 psia covered by this code include forced convection (turbulent flow), nucleate boiling, departure from nucleate boiling, partial film boiling, and film boiling. The code will accommodate a plate mesh, and associated heat generation weighting factors, of a maximum of 50 axial and 10 radial nodes. (auth)

>The U. S. Navy DT-60 dosimeter was evaluated under field type conditions as to its reproducibility and accuracy of gamma x-ray, thermal and fast neutron and mixed radiation responses. Gamma and x-ray responses from 25 to 600 rads at energies in oxcess of 200 kev were found to be accurate within 20% in 92% of 160 dosimeters examined. Because the DT-60 was found to have no detectable fast neutron response, effort was directed toward exaggerating the thermal neutron response to approximate the total neutron dose from a nuclear detonation and also toward eliminating any neutron response in a mixed neutron- gamma field. This was accomplished by various combinations of lithium, paraffin and cadmium shielding. Data indicate that the DT-60 dosimeter can be modified to approximate more closely doses from specific types of mixed radiations; however, this generally detracts from its value in approximating other types of mixed radiation doses. A paired system of dosimeters, in conjunction with one of the fast neutron dosimetry systems is proposed as being the most satisfactory ar rangement to approximate mixed radiation doses to personnel in the field. (auth)

The miscibility gap in the U-Nb system has been established using metallographic and x-ray techniques. The monotectoid temperature is placed at 640 deg plus or minus 2 deg C and the composition limits at that temperature are 65 to 70 at.% Nb and 17.5 plus or minus 1 at.% Hb. The 700, 650, and 600 deg C isothermal sections of the U-Nb- Zr system have also been investigated. Each of the miscibility gaps present in the limiting binary sections was found to be closed by additions of the third element. At 700 deg C the U- Zr gap is closed by addition of less than 5 at.% Nb. The behavior of the Zr-Nb gap is less certain owing to the sluggish reactions close to this binary system but the gap appears to be closed by about 15 at.% U. The U-Nb gap has been studied in more detail and is closed by 14 at.% Zr. To a near approxiation the teniary U-Nb gap can be considered to be bounded by the composition lines 33 at.% U, 14 at.% Zr, and about 20 at.% Nb depending on temperature. A notable feature is that at Nb and Zr compositions approximately corresponding to …

Foliar absorption rates for phosphorus-32 and calcium-45 in beam plants were determined. (C.H.)

A fuel cycle economic study has been made for a 315Mwe graphite- moderated slightly enriched fused-salt reactor. Fuel cycle costs of less than 1.5 mills may be possible for such reactors operating on a ten-year cycle even when the fuel is discarded at the end of the cycle. Recovery of the uranium and plutonium at the end of the cycle reduces the fuel cycle costs to approximates 1 mill/kwh. Changes in the waste storage cost, reprocessing cost or salt inventory have a relatively minor effect on fuel cycle costs. (auth)

The furnace brazing of Zircaloy or Zircaloy-clad nuclear reactor components was investigated. The strength and corrosion resistance of brazements were determined and techniques were developed for preplacing the brazing alloy to prevent contamination and to maintain dimensional stability during brazing. Brazements of high strength and adequate dimensional accuracy were produced, but the brazing cycles impaired the corrosion resistance of Zircaloy in high-temperature steam and water. (auth)

This document details activities of the Hanford Operations Office during the month of January 1958. (FI)

dimensional solution to the general heat transfer equation is presented. Specifically written for application in reactor fuel red design, the code requires cylindrical geometry conditions and input parameters of surface temperature and power density. The maximum number of points for which temperature values may be obtained is 251, and the approximate running time for a typical problem varies from 1.0 to 2.0 minutes. (auth)

BS>The HERD codes furnish a numerical approximation to the one- dimensional, single energy transport equation in slab geometry. The primary purpose of HERD 2 and 3 is to compute blackness coefficients. The limitations of the codes are given and the preparation of input described. (auth)

Past and current work on the study of the movement of dissolved hydrogen in Zircaloy-2 under the influence of thermal and mechanical stress and two-phase activity gradients is reviewed, and the findings are discussed. A program of future work ia presented. (auth)

The laboratory and pilot plant evaluation of Stanleigh concentrate is presented. This concentrate meets all FMPC impurity tolerance limits except those for thorium and chloride. The thorium limit can be met by the condition of phosphate as required for thorium-containing uranium concentrates or by blending with low thorium concentrates. The high chloride content of this material will necessitate the blending or the material with a good quality low-chloride-content concentrate in the National Lead Company of Ohio refinery process. Laboratory digestion and extraction tests indicate that this material should present no other problems in pulse column processing. A pilot plant pulse column test indicated that this material should present no operational problems in the FMPC Refinery. (auth)

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Problems in fuel element development for the Rover program are discussed. Properties of refractory materials which remain solid above 2500 deg C are described. Tensile and compressive creep properties of graphite were deterndined. The compatibility of fuel element materials with the hydrogenous working fluid was also considered. The effect of composition on the properties of graphite is discussed. (M.C.G.)

Short-period transients (less than 15 msec) in the KEWB reactor are apparently controlled primarily by void production resulting from gas evolution in the core. A growth mechanism probably prevails during the short-period excursions which differs from that which occurs at longer periods. Experimental data were examined which showed that the energy transferred to the average bubble is an order of magnitude less than that required to cause bubble growth. It is believed, however, that the validity of the growth model can be established by refinements concerning energy availability deposited in the bubble area and by refinement of bubble-size distribution functions. (J.R.D.)

Calculations were made to estimate the minimum amounts of isotopes, as the element or appropriate compound, which had sufficient power output to raise their temperatures to 200 and 2300 deg C. Construction has begun on a second battery. (For preceding period see MLMCF-58-7-19). (auth)

This document contains 3 reports dealing with the delayed effects of radiation on the eyes of survivors of the atomic explosions in Hiroshima and Nagasaki. In the first study, 1000 persons who were listed as having been in the open and within two kilometers of the hypocenter at the time of the explosion were selected at random from the census files of the Atomic Bomb Casualty Commission for study. In addition, 231 others, comprising the total available number of surviving persons listed at present in the census files as having been within one kilometer of the hypocenter, were examined, as were several hundred others who were contacted through newspaper publicity, referrals from local ophthalmologists, or through hearsay. The survey resulted in bringing in persons having, or having had, a variety of ocular conditions. Those connected with the atomic bomb included the following diagnoses; multiple injuries of eyes and eyelids; keratoconjunctivitis from ultraviolet and ionizing radiations; thermal burn of the cornea and of the retina; retinitis proliferans; and radiation cataracts. The cataracts were the only delayed manifestations of ocular injury from the atomic bomb. The second paper is a case report of a histopathologic study of atomic bomb radiation cataract. The …

Using a special arc-melting technique, sound, homogeneous 100-g cylindrical castings of UC of near stoichi ometric composition were consistently produced. In the casting process developed, UC buttons previously prepared by arc melting the elements were placed over the opening of a graphite mold in a helium-atmosphere arc furnace. When the UC button became fully molten under the arc, it dropped by gravity into the mold. The densities of the resultant castings were about 95% of theoretical. The castings could be successfully machine ground using a water-base cutting fluid. In a preliminary determination of some physical properties of cast UC, the thermal conductivity measured at 100, 400, and 700 deg C was 0.060, 0.053, and 0.060 cal/(sec)(cm)(C), respectively. The mean linear- thermal-expansion coefficient in the temperature range from 20 to 95o deg C was 11.4 x 10/sup -6/ per C. Cast UC encapsuled in stainless steel exhibited good resistance to thermal stress and shock in two series of tests of 100 thermal cycles to 90WC and 100 cycles to 1100 deg C. Heat treating a casting specimen for 1 hr at 1000 deg C produced no significant change in microstructure, but after a subsequent exposure of 1 hr at 1500 deg …