Energy storage and energy extraction are of prime importance for efficient laser action and are affected by the line strengths and linewidths of optical transitions, excited-state lifetimes, nonradiative decay processes, spectroscopic inhomogeneities, nonlinear refractive index, and damage threshold. These properties are all host dependent. To illustrate this, the spectroscopic properties of Nd/sup 3 +/ have been measured in numerous oxide, oxyhalide, and halide glasses. A table summarizes the reported ranges of stimulated emission cross sections, peak wavelengths, linewidths, and radiative lifetimes associated with the /sup 4/F/sub 3/2/ ..-->.. /sup 4/I/sub 11/2/ lasing transition.

Commonly, abatement of hydrogen sulfide emission from a geothermal powerplant requires that hydrogen sulfide dissolved in the cooling water be eliminated by chemical reaction. Oxidation by atmospheric oxygen is the preferred reaction, but requires a suitable catalyst. Nickel is the most potent and thereby cheapest catalyst for this purpose. One mg/L nickel in the cooling water would allow 99% removal of hydrogen sulfide to be attained. A major drawback of catalytic air oxidation is that colloidal sulfur is a major reaction product; this causes rapid sludge accumulation and deposition of sulfur scale. We studied the kinetics and product distribution of the reaction of hydrogen sulfide with oxygen, catalyzed by nickel. Adding sodium sulfite to the solution completely suppresses formation of colloidal sulfur by converting it to thiosulfate. The oxidation reaction is an autocatalytic, free radical chain reaction. A rate expression for this reaction and a detailed reaction mechanism were developed. Nickel catalyzes the chain initiation step, and polysulfidoradical ions propagate the chains. Several complexes of iron and cobalt were also studied. Iron citrate and iron N-hydroxyEDTA are the most effective iron based catalysts. Uncomplexed cobalt is as effective as nickel, but forms a precipitate of cobalt oxysulfide and is too …

During two shallow thermal drilling programs, thermal measurements were obtained in 56 shallow (76.2 m) and one intermediate (457.3 m) depth holes located both onshore and offshore along the southern margin of the Salton Sea in the Imperial Valley, California. These data complete the surficial coverage of the thermal anomaly, revealing the shape and lateral extent of the hydrothermal system. The thermal data show the region of high thermal gradients to extend only a short distance offshore to the north of the Quaternary volcanic domes which are exposed along the southern shore of the Salton Sea. The central thermal anomaly has an arcuate shape, about 4 km wide and 12 km long. Across the center of the anomaly, the transition zone between locations exhibiting high thermal gradients and those exhibiting regional thermal gradients is quite narrow. Thermal gradients rise from near regional (0.09/degree/C/m) to extreme (0.83/degree/C/m) in only 2.4 km. The heat flow in the central part of the anomaly is greater than 600 mW/m/sup 2/ and in some areas exceeds 1200 mW/m/sup 2/. The shape of the thermal anomaly is asymmetric with respect to the line of volcanoes previously thought to represent the center of the field, with its …

Some topics in the standard model of strong and electroweak interactions are discussed, pointing out some problems in this model and indicating how these problems are attacked in some theoretical models. A discussion of radiative corrections in the Glashow-Weinberg-Salam model is given that stresses how these corrections may be measured at LEP and the SLC. Some features of QCD are discussed which are relevant to hadron colliders. In discussing the unsolved problems of the standard model, some aspects of models in which quarks and leptons are composite particles are considered. 85 refs., 44 figs. (LEW)

This paper describes the various laboratory and field tests conducted to assure that flow-induced vibrations do not exist in the piping thermowells of the Fast Flux Test Facility. FFTF thermowells are subjected to a wide range of flowing sodium velocities during testing and operation. Early design work indicated a need to provide special attention to thermowell response in the drag direction at the higher sodium flow rates associated with FFTF testing. The results of this study provide some additional insight into response characteristics of a tube in liquid cross flow with emphasis on motion in the drag direction.

The method is designed for use on recycled uranium materials and is applicable to materials that will yield at least 100 mg of uranium. Typical analysis time is 24 to 30 hours. U-232 can be measured to a lower limit of detection of 1 ppb (U-235 basis).

None

The extraction of methane dissolved in 15 wt % sodium chloride solution at 150/sup 0/C and 1000 psi has been demonstrated using n-hexadecane as the solvent in a sub-pilot scale extraction column operated in a continuous, countercurrent flow mode. Greater than 90% recovery of methane was obtained with solvent/brine mass flow ratios in the range of .040 to .045. The height of an ideal stage in this experimental Elgin-type spray column is estimated to be 1.5 ft. Application of this process on actual geopressured fluids is technically feasible, and when combined with direct drive injection disposal is economically attractive. Design and operation of a methane saturated-brine supply system to provide simulated geopressured fluid continuously at 150/sup 0/C and 1000 psi are also described.

A linear relationship represents the hydrogenation activity decay of catalysts used in four experimental runs reported previously. The weight percent hydrogen in the reactor product oils plotted against oil-catalyst contact time for experimental runs ZBB, ZBC, ZBD, and ZBE reveals a linear decay rate of 0.0083 wt% hydrogen per hour. This is one quantitative measure of catalyst activity decay. The data for the plot incorporate three different catalysts or combinations used to process a PAMCO liquid at 1500 psig, 435C and LVHST of 2 hours. The data set covers run duration of up to 120 hours of oil-catalyst contact. An air driven hydrogen compressor was installed in the Catalyst Life Test Unit to reduce the costs associated with bottle hydrogen. Minor repairs were made on the oil feed pump. Five experimental runs were made with Shell 324 NiMo/Al catalyst using two feedstocks: (1) 40 wt% EDS/EDS raw solvent and (2) 30 wt% SRC-I creosote oil. The EDS feed oil proved to be rather easily hydrotreated as evidenced by 82 to 100% nitrogen removal, essentially complete desulfurization and no catalyst activity decay during 260 hours of continuous operation. Rapid coking resulted from the highly hydrogen deficient SRC/creosote mixture. The Shell 324 …

To study the reaction of water vapour with uranium, we have exposed clean liquid uranium surfaces to H/sub 2/O under UHV conditions. We have measured the surface concentration of oxygen as a function of exposure, and determined the maximum attainable surface oxygen concentration X/sup s//sub O/ as a function of temperature. We have used these measurements to estimate, close to the melting point, the solubility of oxygen (X/sup b//sub O/, < 10/sup -4/) and its surface segregation coefficient ..beta../sup s/(> 10/sup 3/). 11 refs., 5 figs.

Helium analyses have been initiated for the helium accumulation dosimetry materials irradiated in the neutron characterization experiment at RTNS-II. Analyses of the separated isotopes of molybdenum irradiated in the RTNS-I, RTNS-II, and Be(d,n) neutron fields are in progress. The emphasis during the present period was on improving the gas mass spectrometer sensitivity for these samples.