The overall objective of this program is to determine the optical properties of i-Carbon (diamond-like) films and determine if these films can be developed into antireflecting (AR) coatings for silicon solar cells. The i-C films have been produced on glass, silicon, and KCl by radio frequency (RF) plasma decomposition of the alkane gases. Films were also produced on silicon solar cells by low-energy ion beam techniques. These coatings did not perform as well as those made from hydrocarbon gases. Significant progress has been made in understanding the deposition parameters that affect the optical properties of the films. The optical constants n and k have been determined over a large range of process parameters and source gas. The degree of hydrogen incorporation in these films has been studied by SIMS analysis. It was found that the lower optically absorbing films contain more hydrogen. This hydrogen does not, however, manifest itself in fundamental C-H absorption bands in the infrared. Very efficient single-layer quarter-wave i-C AR coatings have been produced on single-crystal and SOC Si solar cells. An increase in cell efficiency of 40% over uncoated cells has been achieved.

Investigations of ion generation and recombination mechanisms in the cesium plasma as they pertain to the advanced mode thermionic energy converter are described. The changes in plasma density and temperature within the converter have been studied under the influence of several promising auxiliary ionization candidate sources. Three novel approaches of external cesium ion generation have been investigated in some detail, namely vibrationally excited N/sub 2/ as an energy source of ionization of Cs ions in a DC discharge, microwave power as a means of resonant sustenance of the cesium plasma, and ion generation in a pulse N/sub 2/-Cs mixture. The experimental data obtained and discussed show that all three techniques - i.e. the non-LTE high-voltage pulsing, the energy transfer from vibrationally excited diatomic gases, and the external pumping with a microwave power - have considerable promise as schemes in auxiliary ion generation applicable to the advanced thermionic energy converter.

The tasks, objectives and completed work are discussed for the legislative and institutional program, cities program, geothermal applications utilization technology, and outreach. The work on the Maryvale Terrace development and the New Mexico Energy Institute are described. (MHR)

Three areas are reported: geothermal administration, geothermal planning, and other geothermal activities. Administration covers the status of the Imperial Valley Environmental Project transfer, update of the Geothermal Resource Center, and findings of the geothermal field inspections. Planning addresses Board of Supervisor actions, Planning Commission actions, notice of exemptions, and the master Environmental Impact Report for Salton Sea. The other activity includes the County Direct Heat Development study; the solicitation for district heating and cooling proposals; the new Geothermal Class II-1 disposal site; the DOE Region IX meeting in Tucson; and USGA designating a new KGRA, the East Brawley KGRA, the Westmoreland KGRA, and revising the southern border of the Salton Sea KGRA. (MHR)

This analysis of advanced wastewater treatment systems for coal gasification plants highlights the three coal gasification demonstration plants proposed by the US Department of Energy: The Memphis Light, Gas and Water Division Industrial Fuel Gas Demonstration Plant, the Illinois Coal Gasification Group Pipeline Gas Demonstration Plant, and the CONOCO Pipeline Gas Demonstration Plant. Technical risks exist for coal gasification wastewater treatment systems, in general, and for the three DOE demonstration plants (as designed), in particular, because of key data gaps. The quantities and compositions of coal gasification wastewaters are not well known; the treatability of coal gasification wastewaters by various technologies has not been adequately studied; the dynamic interactions of sequential wastewater treatment processes and upstream wastewater sources has not been tested at demonstration scale. This report identifies key data gaps and recommends that demonstration-size and commercial-size plants be used for coal gasification wastewater treatment data base development. While certain advanced treatment technologies can benefit from additional bench-scale studies, bench-scale and pilot plant scale operations are not representative of commercial-size facility operation. It is recommended that coal gasification demonstration plants, and other commercial-size facilities that generate similar wastewaters, be used to test advanced wastewater treatment technologies during operation by using …

Extensive NMR measurements of the proton relaxation times have been performed on low (i.e., alpha-phase) and intermediate (i.e., alpha'-phase) hydrogen concentrations in TiCr{sub}2H{sub}x with both the hexagonal Cl4 and cubic Cl5 Laves structures. The relaxation times indicate rapid diffusion rates above 200 K for all the TiCr{sub}2H{sub}x phases; however, large differences in the diffusion activation energies are observed. This behavior is associated with the hydrogen interstitial site occupancies and diffusion pathways becoming restricted in the Cl4 structure.

"Results of a reconnaissance geochemical survey of the Thief River Falls Quadrangle, Minnesota and North Dakota, are reported. Statistical data and symbol plots for uranium and uranium-related variables are presented for 471 groundwater and 342 stream sediment samples. Also included is a discussion on geologic factors considered significant in evaluating the potential for uranium mineralization."

This report presents field and laboratory data for 585 groundwater samples and 201 stream sediment samples collected from the Grand Forks quadrangle in North Dakota and Minnesota.

This report presents field and laboratory data for 642 groundwater samples and 238 stream sediment samples collected from the Fargo quadrangle in North Dakota and Minnesota.