The electron paramagnetic resonance (EPR) of color centers in additively colored KCl crystals is measured to observe the effects of optical bleaching at room temperature. Earlier measurements on the F-center are confirmed and the susceptibility is measured at 78 and 300 deg K over five decades of power, including the very low power region. The width and the saturation properties of the individual multiplets are studied in detail and the technique of making E PR measurements on inhomogeneously broadened lines is discussed. A calculation is presented which shows that a slight departure from a Lorentzian multiplet shape can account for the saturation data. The bleached crystals show a resonance which has a width of 35 gauss and a different rate of saturation than the F- center. This resonance is associated with the B-band which appears in the optical absorption. (auth)

Apparatus for the performanee testing of SNAP 10A thermoelectric elements was designed, constructed, and is now in operation. Elements may be tested for any desired length of tfme up to 1400 deg F and in a vacuum of 1 x 10/ sup -5/ of Hg. The equipment used for these tcsts may also be utilized for measuring Seebeck coefficient and resistance as a function of temperature. Element performance is derived from the data on voltages and temperatures. The performance variables which are reported in graphic form are as follows: loaded output voltage at any desired DELTA T; open circuit output voltage at any desired DELTA T; power output under optimum load conditions; current produced under matched load conditions; and internal resistance of the element. (auth)

Abstract: "The electron paramagnetic resonance (EPR) of color centers in additively colored KCl crystals is measured to observe the effects of optical bleaching at room temperature. Earlier measurements on the F-center are confirmed and the susceptibility is measured at 78 and 300 deg K over five decades of power, including the very low power region. The width and the saturation properties of the individual multiplets are studied in detail and the technique of making EPR measurements on inhomogeneously broadened lines is discussed. A calculation is presented which shows that a slight departure from a Lorentzian multiplet shape can account for the saturation data. The bleached crystals show a resonance which has a width of 35 gauss and a different rate of saturation than the F- center. This resonance is associated with the B-band which appears in the optical absorption."

Experiments with unirradiated Consolidated Edison reactor ThO/sub 2/-- U0/sub 2/ fuel pellets indicated that uranium losses to Sulfex and Darex decladding solutions were proportional to the U0/sub 2/ content of the pellets. For example, after 7 hr, losses to boiling initial Darex solution (5 M HNO/sub 3/- -2 M HCl) were 0.45 and 0.65% from pellets containing 3 and 9% U0/sub 2/, respectively. The initial rate of dissolution of these pellets in 200% excess boiling 13 M HNO/sub 3/--0.04 M NaF-0.1 M Al(NO/sub 3/)/sub 3/ was essentially independent of the U0/sub 2/ content. Rates were 2.1, 3.0, and 2.4 mg min/sup -1/ cm/sup -2/ for pellets contdining 3, 6, and 9% U0/sub 2/, respectively. The presence in the dissolvent of the soluble neutron poisons H/sub 3/B0/sub 3/ and Cd(NO/sub 3/)/sub 2/ in concentrations up to 0.1 M and 0.075 M, respectively, had little effect on the rate of dissolution of sintered UO/sub 2/-- ThO/sub 2/ fuel pellets. (auth)

This report considers the theoretical evaluation of a system for gaining increased control strength and increased control lifetime and presents a theoretical model which is applicable to conventional multigroup diffusion theory.

A process for recovering uranium from carbonate leach liquors by extraction with quaternary ammonium compounds was developed and evaluated in bench-scale continuous equipment with synthetic liquors. Uranium was recovered from the solvent by direct precipitation with sodium hydroxide --sodium carbonate solution. Results with relatively pure synthetic carbonate liquors were favorable, but attempts to treat a highly contaminated leach liquor from a western mill were relatively unsuccessful owing to interference from sulfate, chloride, thiocyanate, molybdenum, vanadium, and organic matter present. The process is therefore not considered competitive with the precipitation process used in several western carbonate-leach mills. (auth)

Stability tests are to be made in the VBWR (boiling water reactor). The tests are of three types: steady state measurements, rod oscillator tests, and transient tests.