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An investigation was conducted to determine the effect of a wide operational temperature range on the output of a small photomultiplier tube (PMT). This PMT is similar to the RCA 8571 miniature PMT. A calculator based instrumentation system is described including programming techniques used to reduce and display data. Also described is a Light Instrumentation System with specially designed fiber optic light guides which supplies light to the PMT to allow measurement of the PMT output with respect to temperature. (auth)

The dc joule losses per unit length in a theta-pinch compression coil are calculated and compared to the thermonuclear energy production for two different methods of plasma heating. In the first method, conventional staged theta-pinch heating is assumed. In the second method, laser heating by long wavelength irradiation from the ends is assumed. Reactor parameters are calculated, and it is shown that for circulating power fractions to be 20% or less, the plasma radius must be at least a few cm in size. (auth)

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From surface effects in controlled thermonuclear fusion devices and reactors meeting; Argonne, Illinois, USA (10 Jan 1974). The sputtering by ftssion fragments of Cu, Al, and Nb doped with 0.1 at.% /sup 235/ and bombarded with thermal neutrons was investigated. This was primarily a search for micron size particles emitted from the surfaces of the doped sources. Kaminsky et al., have observed large particles (several microns in size) emitted from the surface of samples bombarded by 14 MeV neutrons, with a maximum knock-on energy of 600 keV in Nb. The fission energy deposition of 200 MeV should be more than adequate to yield any observable effects that might be present at 600 keV. The concentration of flssion events was 10 times the concentration of knockons in the Kaminsky experiments. With scanning electron microscope and energy dispersive x- ray analyses of sputtering collectors both before and after irradiation, no sputtered particles were found larger than one detection limit of 0.1 mu . (auth)

A formalism is developed for calculating ionization in laser driven hydrodynamics codes. Starting from equations for collisional ionization and radiative recombination, approximations are made to allow their easier solution. Steady-state solutions are assumed to be of most importance to the extent that transient solutions to the rate equations are ignored. Free-bound radiation is also treated in a hydrogenic approximation. (auth)

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Measured neutron elastic and inelastic scattering cross sections for / sup 63/Cu and /sup 65/Cu between 5.50 and 8.50 MeV are presented and compared with elastic data of Holmqvist and Wiedling and with ENDF/B III MAT 1085 and 1086. The elastic differential cross sections are in fair agreement with those of Holmqvist and Wiedling in shape. The angle-integrated differential elastic cross sections are systematically higher by as much as 28% than those of Holmqvist and Wiedling above 5 MeV, a situation similar to that found in comparing the two sets of data for other elements. ENDF/B III MAT 1085 and 1086 angular distributions underestimate the elastic forward peak below 20 deg. when compared with experimental results and display unphysical fluctuations due to the use of a Legendre series of order 20 where order 9 is the highest required by the data. An evaporation model with temperature ranging from 0.8 to 1.05 MeV reasonably describes inelastic scattering to levels in the residual copper nuclei of excitation energy above 3.2 MeV. (auth)

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The successful application of a mass spectrometric method to determine the source of oxygen diffusion into the container material of a radioisotopic fuel capsule is described. The source was chiefly the oxide fuel (/sup 238/PuO/ sub 2/) and not the atmosphere. This could be accomplished by determining the / sup 18/O//sup 16/O ratio in the tantalum alloy material, because the /sup 18/O content of the fuel had been reduced to minimize alpha -n reactions. The /sup 18/O//sup 16/O ratio was ~5.5 x 10/sup -4/ for fuel as compared with 2 x 10/sup - 3/ for air. The radiochemical method, based on an alpha -n reaction, could not be applied because of the very low alpha -particle flux in the liner material. (auth)

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From surface effects in controlled thermonuclear fusion devices and reactors meeting; Argonne, Illinois, USA (10 Jan 1974). The sputtering yield of gold bombarded with fission neutrons was studied in the CP-5 reactor. Bulk single crystals were used at near liquid helium temperature. Overall sputtering yields ranged from 1 x 10/sup -3/ to 6 x 10/sup -3/ sputtered gold atoms per incident neutron for doses ranging from 2.1 x 10/sup 17/ to 5.5 x 10/sup 17/ (nvt > 0.1 MeV). Results are roughly an order of magnitude larger than many previoualy reported sputtering yields. Sputtering patterns have not been pursued yet, due to sufficiently high background radiation. (auth)

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Some preliminary results obtained from experiments designed to test the feasibility of the Venetian Blind, direct energy-conversion concept are discussed. A two-stage unit was built and tested and found to have an overall efficiency of 65% for an energy spread of from 330 to 1000 eV. The calculated efficiency was 69% leaving a 4% discrepancy. This discrepancy seems to result from the slight transparency in the backward direction of the ribbons of the converter. (auth)

Heat soak periods were completed on the remaining 49 couples of the compatibility matrix which was put on test in May 1973. Examination of the 18 couples which were taken off test in August 1973 was completed. The planned short-term ceramic compatibiliiy matrix exposures were completed, and optical microscope examinations were done. Experiments were started to develop fabrication techniques for preparation of an 11-couple compatibility matrix scheduled for FY 1974. The design of this matrix was finalized, and component procurement was started. Free energy calculations were made for the reactions of Cm/sub 2/O/sub 3/ fuel with Haynes 188, Ta-10% W, and TZM alloys and with beryllium. Measurements of the helium release characteristics of hot-pressed / sup 244 Cm/sub 2/O/sub 3/ were started at 500, 650, and 800 deg C. A vapor pressu re determination was run on curium metal in the temperature range from 900 to 1800 deg C. Vapor pressure measurements of/sup 244/Cm/sub 2/O/sub 3/ in the range from 1200 to 1600 deg C were begun these will continue next quarter. Examinations by x-ray diffraction were made on materials resulting from exposures of/sup 244/Cm/sub 2/O/sub 3/ to flowing seawater, boiling scawater, and dry air as well as on/sup 244/Cm/sub …

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The processing of nuclear rocket (Rover) fuels requires high concentrations of hydrofluoric acid and nitric acid in the dissolver solution to dissolve the uranium and niobium. The resulting dissolver solutlon is highly corrosive and requires the addition of aluminum nitrate to complex the free fluoride'' and reduce corrosion on stainless steel processing equipment located downstream from the dissolver. The dissolver solution is very sensitive to aluminum nitrate addition; excessive aluminum nitrate results in precipitation of Nb/sub 2/O/sub 5/. Insufficient aluminum nitrate results in precipitation of AlF/ sub 3/, and the solution remains corrosive. The stability range of the complexed dissolver solution is narrow and time dependent. The stability range was determined expenimentally to vary from 24--30% for a 2-hr period and from 0-10% for a 24-hr period. The stability range is increased to 40% over a 5-day peniod when the solution is diluted and adjusted for solvent exrraction feed. (auth)