A thermoelectric generator which produces 100 watts of electrical power continuously over a six-month operational life in a space environment was designed. It employs the heat produced by the decay of Cm/sup 24/ as the source of power. Uniform output over the operational life of the generator is accomplished by means of a thermally actuated shutter which maintains the hot junction temperature of the thermoelectric conventer at a constunt figure by varying the amount of surplus heat which is radiated directly to space from the heat source. The isotopic heat source is designed to safely contain the Cm/sup 242/ under conditions of launch pad abont and rocket failure, but to burn up upon re-entry to the earth's atmosphere from orbital velocity. (W.L.H.)

The Stationary Low Power Reactor No. 1 is a three Mw boiling water reactor designed to demonstrate the feasibility of a nuclear reactor to supply electrical power and space heat for remote sites. In addition to performance evaluation the facility provides training for military personnel. The reactor was operated for 1159 hr during the quarter for a total core burnup of 20.3%. Power generation was 103.7 Mwd for a total power accumulation of 466.9 Mwd. Eight malfunctions occurred during the quarter for a total unscheduled downtime of 40 hr 44 min, As a result of malfunctions, aluminum keys will be installed on the control rod drives, instrument well covers were removed, and an order has been placed for a station auxiliaries breaker with a higher temperature rating. Data were taken on seven tests during the quarter. Four of these are expected to be completed during the next quarter. All equipment items on order for the SL-1 power extrapolation expansion program are scheduled to be delivered before June 15, 1960. Although condenser dampers and damper controls, process instrumentation, equipment cabinets, and the radiation monitoring equipment have not yet been ordered, construction will not be delayed. The two tie-ins to the existing …

The reduction characteristics of plutonium trichloride are investigated. A flowsheet for batch reduction with Ca is included. (J.R.D.)

The concentrations of and activities due to N/sup 16/ and N/sup 17/ in the HFIR primary coolant water were calculated. At the pressure vessel exit, the N/sup 16/ activity is 3.9 x 10/sup 6/ dis/secml and the N/sup 17/ activity is 6.9 x 10/sup 2/ dis/sec-ml. Comparison of the N/sup 16/ activity with the data obtained from the ORR water system indicates that the calculated results are slightly conservative. (auth)

A study of the dynamic behavior of the Merchant Ship Reactor Pressurized Water Loop was made using the Reactor Controls Analog Facility. Computer curves show the predicted response of the loop temperatures to normal load changes and component failure accidents. Except for complete flow stoppage, which was not investigated here, the safety system was shown to be adequate in curbing loop temperature excursions due to postulated accidents. (auth)

BS>The aqueous corrosion of Mg alloys was investigated at 53 to 150 deg C. Corrosion rates rose rapidly with temperature, reaching about 3 mils per day at 150 deg C for AZ-31 STAMg-2.5 to 3.5 wt.% Al-0.7 to 1.3 wt.% Zn-0.2 wt.% Mn!. Additions of small amounts of Cu and/or Ni to the basic AZ-31 composition reduced the corrosion rate at 150 deg by a factor of about two. Sn may be advantageously substituted for Zn in AZ-31. Control of the pH in the range between 6 and 7 and maintenance of a fluoride concentration in the range between 1 and 10 ppm reduced the corrosion rate of AZ-31 to about 0.1 mil per day at 150 deg C. (auth)

The hazards evaluation was modified to reflect certain changes made to the equipment as a result of operating experience. These changes included: the addition of a startup interlock circuit; the modification of a startup interlock circuit; several minor modifications to the control rod actuators; and the addition of the tube-sheet cooling system. (M.C.G.)

A method is described for observing the uptake of Fe by rat bone marrow cells in vitro. Results of experiments on effects of anemic serum and human erythropoietin are presented with a brief discussion. It is concluded that the differences in uptake of Fe/sup 59/ are the result of isotope dilution. (auth)

Zirconium anodizes similarly to tungsten in respect to the change of interference colors with applied voltage. However, the oxide layer on tungsten cannot reach as great a thickness. Hafnium does not anodize in the same way as zirconium but is similar to tantalum. By measuring the interference color and capacitative thicknesses on zirconium (Grades I and III) and a 2.5 wt.% tin ailoy, the film was found to grow less rapidly in terms of capacitance than in terms of iaterference colors. This was interpreted to mean that cracks develop in the oxide as it thickens. The effect was most pronounced on Grade III zirconium and least pronounced on the tin alloy. The reduction in capacitative thickness was especially noticeable when white oxide appeared. Comparative measurements on Grade I zirconium and 2.5 wt.% tin alloy indicated that the thickness of the oxide film on the tin alloy (after 16 hours in water) increased more rapidly with temperature than the film on zirconium. Tin is believed to act in ways to counteract the tendency of the oxide to form cracks, and to produce vacancies which promote ionic diffusion. (auth)

This document presents experimental data obtained during a series of tests which were completed at 105-D and DR Reactors in February and March, 1960. No analysis of the data is included in this document. The tests were: PT-301-I, II -- Reactor cold, full flow, BPA power failure; PT-278-A, III B -- 1170 MW, full flow, BPA power failure; and PT-278-A, II -- 1190 MW, full flow, poison push causing bulk surge and scram.

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Decontaminability measurements of 34 protective coatings (primarily vinyls and epoxies) and 10 comparative control surfaces (metals, glass, and plastics) highly contaminated with either mixed fission products from typical Purex waste or Oak Ridge National Laboratory Thorex waste did not indicate any unusual improvement over coatings tested in 1950 (AECD-2296). These measurements and chemical rcsistance tests were made of the protective coatings in common acids, alkalis, and deionized water at 81 and 120 deg F as a guide in the selection of coatings for radiochemical plant applications and to determine if coatings containing water vehicles could be substituted for coatings containing more hazardous organic solvent vehicles. Vinyl base coatings were superior in both decontaminability and chemical resistance. The two watervehicle coatings evaluated were markedly inferior to organic-vehicle vinyls. A vinyl wallpaper'' was decontaminated poorly with the reagents used. Water and 3M HNO/sub 3/ removed Purex contaminants relatively efficiently but were relatively ineffective for the removal of Thorex contaminants. Coatings determined to be sufficiently decontaminated from Purex waste by a water flush and acid scrub and to be of superior resistance to common acids and alkalis are given. (auth)

The design, development, and operation of metaldiaphragm service pumps for aqueous homogeneous reactojs are discussed. It is shown that with proper design and materials selection, the dlaphragm heads and check valves can operate continuously for about two years. (C.J.G.)

The hot-water corrosion resistance and mechanical properties of niobium and a number of its alloys were evaluated relative to their usefulness in pressurized-water thermal reactors. Unalloyed niobium was found to be rapidly attacked by 600 and 680 deg F water and 750 F steam. A number of alloying additions were found which markedly improve the corrosion resistance of niobium. Of these, binary and ternary combinations of chromium, molybdenum, titanium, vanadium, and zirconium were among the most effective. Many of these alloys exhibited as low or lower weight gains than those obtained for Zircaloy-2 under similar test conditions. Most of the niobium-base alloys tested for strength exhibited excellent resistance to creep at temperatures up to 1200 deg F under stresses through 20,000 psi. (auth)

The diffusion coefficient of tracer amounts of Au/sup 198/ in gamma U is described by an Arrhenius-type equation: D = 4.86 x 10 cm/sup -3/sec exp(-30,400 cal/mol/RT). The values of D/sub 0/ and the activation energy are close to those for self-diffusion in gamma U, indicating that the low activation energy for self- diffusion is due to a general weakness of the lattice rather than to easy compressibility of the U atom. (auth)

The reactions pi /sup -/ + p yields p + p + n and pi /sup -/ + p yields p + d were investigated. The calculations are based on thirdorder perturbation theory with pseudoscalar coupling between nucleons and pions and with a phenomenological treatment of the nucleon-nucleon interaction in the final state. The final-state interactions of the antinucleon are neglected. Cross sections are given in graphical form for the reactions and for trsnsitions between eigenstates of isotopic spin. The final-state nucleon-nucleon interaction is shown to have a lnrge effect on the cross sections. The cross section for the reaction pi /sup -/ + p yields p + d is found to be relatively large. At an energy of 10 Mev abcve threshold in the center-of-momentum system the ratio of this cross section to that for pi /sup -/ + p yields p + p + n is about 5: 1. At an energy of 40 Mev above threshold this ratio hns decreased to 1: I. The total cross section for the reaction leading to the unbound final state is calculated by assuming a modified Fermi statistical model. At an energy 100 Mev above threshold, this cross section is approximately …

Cutoff energies were calculated for height/diameter (H/D) values of 1, 3, 6, and 11.25 for cadmium cylinders. These are presented along with the values for H/D = 2 for comparison. Similar values for boron filters for H/D values of 1 and 2 are shown. (M.C.G.)

An investigation was made of the behavior under irradiation of uranium- rich corrosion-resistant alloys with the following nominal compositions: U--3 wt.% Nb, U--3 wt.% Nb--0.5 wt.% Sn, U/sub 3/Si (U--3.8 wt.% Si), and U--2 wt.% Zr (diffusion heat treated). The U--3 wt.% Nb alloy in the rolled and gamma- quenched condition was highly unstable dimensionnlly under irradiation. The U--3 wt,% Nb--0.5 wt.% Sn alloy, in the cast and gamma-quenched condition, was only moderately stable dimensionally. The U/sub 3/Si in the cast condition showed good dimensional stability but in the extruded condition developed moderate anisotropic growth. Clad Nb--0.5 wt.% Sn, UaSi (U--3.8 wt.% Si), and U--2 wt.% Zr (diffusion heat treated). The U--3 wt.% Nb alloy in the rolled and gamma- quenched condition was highly unstable dimensionally under irradiation. The U--3 wt.% Nb--0.5 wt.% Sn alloy, in the cast and gamma-quenched condition, was only moderately stable dimensionally. The U/sub 3/Si in the cast condition showed good dimensional stability but in the extruded condition developed moderate anisotropic growth. Clad rods of diffusion heat treated U--2 wt.% Zr alloy were generally highly stable. Only the U/sub 3/Si and U--2 wt.% Zr alloy specimens retained a significant degree of their preirradiation corrosion resistance. (auth)

A number of organisms have been examined for their ability to produce electron-spin-resonance signals at low temperatures in response to illumination. The efficiency of the response is of the order of not less than 5%, and the wavelength for maximum response is generally slightly on the longer side of the wavelength of maximum absorption, with a minimum appearing at the wavelength of maximum absorption.

Data on the properties, constitution, compatibility, radiation behavior, fabrication, preparation, storage, and handling of uranium, thorium, and plutonium carbides are reviewed. 187 references. (C.J.G.)

The external holdup of expensive materials and associated capital costs for the heat removal systems of fluid fuel breeders were determined. The aqueous homogeneous and molten salt breeders were found to contain substantially less uranium holdup external to the core than the liquid metal fueled breeder. The cost of heat removal and turbogenerator plant equipment for the three systems was compared. (auth)

The neutrons in an operating nuclear reactor are generated primarily by the fission events which are taking place. The great bulk of these relatively high energy or fast neutrons are slowed down or thermalized by a series of elastic collisions with the moderator nuclei which comprise the bulk of the volume of the reactor core. Once slowed down, the neutrons diffuse through the reactor core until they are absorbed or eliminated by some other process. Each of these three groups of neutrons, i.e., the fast or source neutrons, the intermediate or slowing down neutrons, and the slow or thermal neutrons, has a characteristic energy distribution. At a constant power level or rate of fissioning, an equilibrium is soon established among the groups at any point in the reactor. If it is assumed that a smooth transition exists between the different energy groups, it is possible to evaluate the entire neutron spectrum at a point in the reactor by determining the parameters which characterize each of the three groups. This has been done in the F Reactor Quickie Facility using radioactivants.

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Low attack rates (0.1 to 0.5 mpy) were displayed by coupon specimens of type 347 stainless steel, titanium RC-55, and Zircaloy-2 which were exposed for 2877.5 hr in an oxygenated slurry of Th--8% U oxide, 116.5 hr in water, 6.9 hr in 5% HNO/sub 3/, and 4.3 hr in 3% triscdium phosphate during mns SM-6 through SM-9 in the slurry blanket mockup. The leading coupon of type 347 stainless steel showed a slightly higher rate than the other stainless steel ccupons due to entrance effects. Specimens of SA-212-B carbon steel displayed average attack rates of 2.9 mpy. (auth)