The limited supply of relatively long-half-life isotopes having a reasonably high power density and the low conversion efficiencies obtainable with thermoelectric devices have so far limited the power output of isotope-fueled sources of electric power to several tens of watts. In addition, the high cost of the available isotopes results in a very large expense for isotope-fueled generators producing several hundred watts. It appears that a small, minimumweight, conduction-cooled reactor is an attractive alternate to the isotope-fueled power supplies in the 200-w size range. The proposed reactor is a small, high-density fast core of U/sup 233/ surrounded by a beryllium reflector. This approach, generally speaking, gives a reactor that is more compact and of lighter weight than can be obtained with a moderated system having a softer neutron spectrum. In the reactor design, the path of heat flow is from the core to the inner reflector and then to the thermoelements in close contact with the inner reflector. The reject heat flowing from the thermoelement cold junctions enters the outer pontion of the reflector, which acts as the heat sink and conducts the reject heat to the large, circular, tapered-fin radiator which is attached to the reflector. Survey physics calculations …

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This report has two volumes, volume 1 contains the summary and detailed description of plant design, volume 2 contains a comprehensive nuclear evaluation of the reactor core.

This report includes the nuclear evaluation that has been conducted for the purpse of studying those problem areas which are expected to increase in severity as the core size is increased to produce 1000 MWE.

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The computer program 1559/RE is an experimental IBM-704 code in FORTRAN language for computing the resonance integrals of isotopes in mixtures in the presence of hydrogenic moderation. There may be up to four isotopes, each with no more than 75 resolved resonance levels. Doppler broadening and interference scattering are included No estimate is made of contributions from unresolved resonances. Typical running times are 30 min (with no Doppler broadening) to 90 min (with Doppler broadening) for problems involving 67 levels and unit lethargy widths. Input and theory are discussed, and a typical listing is given. (auth)

The purpose of this report is to describe the operation of the Acceptance Test Facility (ATF) and testing of SNAP 10A Auxiliary Power Units (APU) in the facility.

Dormant seed of Quercus alba and Quercus rubra were irradiated with gamma rays from Co/sup 60/ to determine the efiect on cytological and morphological expression in the resulting seedlings. Investigations included varying moisture content and physiological state of the seed prior to treatment, and preliminary evaluation of induced mutation. The following observations were made. The lethal radiation exposure was the same for both species although there were differences in germination within the treatment range of 1 to 10kr. Quercus alba showed an LD/sub 50/ of 6kr with a significant regression for radiation level. The regression of germination on radiation level was not significant for seed of Quercus rubra, but germination was suppressed at the higher levels. These species differences are thought to be due more to physiological than genetic factors. Height growth in the two species was complexed by sprouting in reaction to radiation damage of the apical primordia. Seedling height at the end of one year was not a significant measure of radiation damage. The type of sprouting obtained is discussed in relation to diplotonic selection within the irradiated embryonic primordia. Growth of the root at 10 days following inception was established as a macro-measure of genetic damage. Changes …

A General Electric XRD-5 diffractometer equipped with a scintillation counter, a pulse height discriminator, and a modified version of the Model X-86G high-temperature diffractometer attachment, was modified for x-ray diffraction analysis at temperatures up to 3000 deg C. These modifications include frame assemblies, viewing port, filament materials, and thermocouples. (D.L.C.)

Declassified 4 Sep 1973. A hot-working device for compression of graphite bodies was used to deform cylindrical specimens of matrix graphite containing ZrC or UC-ZrC particles to strains of the order of 30% at temperatures of 2400 to 2900 deg C. The graphite bodies containing ZrC particles (chosen as representative carbide particles) were found to be more plastic near 2500 deg C than similar bodies containing no carbide particles. Microradiographic techniques were used to determine diffusion coefficients of U and Th on actual coated particles by nondestructive means. A tentative energy of activation for the migration of uranium from UC/sub 2/ particles into PyC coatings was determined over the temperature range 1850 to 2300 deg C. The penetration of U into the coatings is not uniform but occurs radially in localized positions, and then spreads circumferentially, creating a banded structure. These results show the importance of the structure of PyC in regard to the diffusion of both fuel and fission-product materials. It was also observed that the diffusion of U is considerably more rapid in the direction parallel to the layer planes in the PyC than it is in the perpendicular direction. Tests with PyC-coated (U, Zr)C particles in graphite-matrix …

Work in aerospace safety analysis, research, development, and testing is discussed. Studies for the SNAP program are outlined. The engineering andd test program for aerospace safety ls described. (M.C.G.)

From Health Physics Society 8th Annual Meeting, New York, June 1963. The Atomic Energy Commission's research program on atmospheric radioactivity and fallout is reviewed. The main purpose of the research program is to provide an increasingly complete and sound scientific basis for the prediction of radiation doses to man that may result from the introduction of radioactive material into the atmosphere. Techniques and computation models for making such predictions are discussed. Emphasis is placed on studies of world-wide transport and distribution phenomena associated with fallout from weapons tests and low- altitude local problems arising from industrial and laboratory operations. The program is conducted through research contracts with universities, industrial organizations, and interagency agreements with other government agencies and AEC facilities. A list is appended of current participants in the program. (C.H.)

The assessment (by ground testing) of effects of mechanical actions, thermal and chemical interactions, and nuclear reactions upon tue safety of nuclear power sources that are intended for aerospace applications is discussed. Progress in general studies and in testing of SNAP-9A and -10A is reviewed. (T.F.H.)

Alpha-gamma angular correlation measurements were made with solid sources of Am/sup 243/ and with liquid sources containing either Am/sup 243/ or an even-even alpha emitter in dilute perchloric acid solutions. Even-even alpha emitters studied are U/sup 232/, Th/sup 230/, and Ra/sup 226/ . Thicknesses of the soli d sources were controlled so that the neptunium recoils from one source were stopped in Am/sub 2/O/sub 3/, while recoils from the other sources were stopped in the aluminum, gold, or mica backing on which the sources were vaporized. The liquid sources were films consisting of 3 microliters of solution placed between a rubber hydrochloride membrane and a microscope cover glass, 1 cm/sup 2/ in circular cross section. The perchloric acid concentration of the liquid sources ranged from 0.5 to 3.0 molar. All of the angular correlations obtained with solid Am/sup 243/ sources were attenuated, the average attenuation coefficients being 0.29 450 deg C in a 0.01 for sources in which recoils were stopped in Am/sub 2/O/sub 3/, 0.20 450 deg C in a 0.01 for sources in which recoils were stopped in mica, 0.52 450 deg C in a 0.02 for sources in which recoils were stopped in gold, and 0.67 450 …

This summary on various flow induced vibration tests considers the four major types of tests which could accomplish, in part or in entirey, the experimental verification of design concepts for the support system for the NRX-A design.

Development of the reference adapter valve for the alternate on-power refueling machine head used in connection with CANDU-type power reactors is described. Results of valve component testing are included. (J.R.D.)

This report discusses the conference on direct energy conversion.

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This is an analysis, based on a test conducted by LASL personnel, to determine whether relative expansion of two pieces of graphite under bundling loads would result in failure of the graphite.

The reactivity characteristics of the operating Yankee Core I are analyzed. Calculations of kinetic parameters, kinetic coefficients, control rod and boron worth, core lifetime and burnup rate, and fission product poisoning, are described. A large amount of experimental data obtained during Core I operation is included and comparisons are made between prediction and experiments. (auth)

The report is divided into 4 major parts with several sections in each part. Separate abstracts were prepared for all sections in Parts I and II except 8 and 9 (containing information on mass spectrometry and microscopy). A summary of service analyses is given in Part III, and information concerning the ORNL master analytical manual is presented in Part IV; abstracts were not prepared for these. (J.R.D.)

An important mechanism in the transport and deposition of very small particles from gas streams to the surfaces of a conduit is diffusion due to the Brownian movement of particles. The heat-mass analogy is used to describe the diffusion, and equations are derived for the deposition of fission products from a gas stream to wall surfaces as a function of the distance along the conduit. Effects of radioactive decay on the validity of the heat-mass analogy in applying standard heat transfer relations to predict material transfer to wall surfaces are discussed. (auth)

The effects of 1-hr anneals at 1000 and 1800 deg F on the mechanical properties of Type 347 stainless steel specimens taken from the ETR J-10 pressure tube after fastneutron (> 1 Mev) exposures of approximates 7.1 x 10/sup 21/ nvt were studied. The pressure tube operated at a maximum temperature of approximates 750 deg F in a stressed condition. Testing was done at 75 and 750 deg C. Uniform elongations were increased from approximates 1% in the as- irradiated material to 15 and 25%, respectively, by the 1000 and 1800 deg F anneals. The 1000 deg F annealing appeared to produce a better combination of mechanical properties. The microstructure of unirradiated, as-irradiated, and postirradiation-annealed specimens were very similar except for two specimens inadvertently heated above 1800 deg F during annealing. (auth)