Theoretical work of two decades ago adequately explained the transport behavior and effectively guided the development of thermoelectric materials of high conversion efficiencies of conventional semiconductors (e.g., SiGe alloys). The more significant contributions involved the estimation of optimum doping concentrations, the reduction of thermal conductivity by solid solution doping and the development of a variety of materials with ZT approx. 1 in the temperature range 300 K to 1200 K. It was also shown that ZT approx. 1 is not a theoretical limitation although, experimentally, values in excess of one were not achieved. Work has continued with emphasis on higher temperature energy conversion. A number of promising materials have been discovered in which it appears that ZT > 1 is realizable. These materials can be divided into two classes: (i) the rare-earth chalcogenides, which behave as itinerant highly-degenerate n-type semiconductors at room-temperature, and (ii) the boron-rich borides, which exhibit p-type small-polaronic hopping conductivity.

The advantages of pulsed excimer lasers for semiconductor processing are reviewed. Extensive comparisons of the quality of annealing of ion-implanted Si obtained with XeCl and ruby lasers have been made. The results indicate that irrespective of the large differences in the optical properties of Si at uv and visible wavelengths, the efficiency of usage of the incident energy for annealing is comparable for the two lasers. However, because of the excellent optical beam quality, the XeCl laser can provide superior control of the surface melting and the resulting junction depth. Furthermore, the concentrations of electrically active point defects in the XeCl laser annealed region are 2 to 3 orders of magnitude lower than that obtained from ruby or Nd:YAG lasers. All these results seem to suggest that XeCl lasers should be suitable for fabricating not only solar cells but also the more advanced device structures required for VLSI or VHSIC applications.

This GEOTHERM sample file contains 1535 records for California. Three computer-generated indexes give one line summaries of each GEOTHERM record. Each index is sorted by different variables to assist in locating geothermal records describing specific sites. 7 refs. (ACR)

Letter from Joan McKesson to Rigdon Edwards discussing his plans to attend the 1984 WASP Reunion, and encouraging him to urge other instructors to attend as well.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas.

Partial abstract: A 1:100-scale (undistorted) hydraulic model, reproducing Mission Bay Harbor, approximately 3 miles of shoreline, and sufficient offshore area to permit generation of the required test waves, was used to investigate the arrangement and design of proposed structures for (a) improving hazardous entrance conditions, (b) reducing surge inside the harbor, and (c) eliminating potential flood hazards. The original proposal for harbor improvement consisted of a 2,200-ft-long offshore breakwater. The proposed structures for river flood control consisted of (a) a 1,200-ft-long weir in the middle jetty, (b) various south jetty extensions, and (c) diversion dikes on the middle jetty.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Drumming is first described for five North American stonefly species, Acroneuria evoluta, Doroneuria baumanni, Isoperla namata, Chernokrilus misnomus, and Pictetiella expansa. Signals of Acroneuria lycorias, Phasganophora capitata and Isoperla signata are further described. Drumming was not recorded from Amhinemura delosa. Signals of A. evoluta are the most complex yet recorded in Plecoptera. Doroneuria baumanni, P. expanse, C. misnomus and P. capitata have 2-way exchanges. Male D. baumanni produce two prolonged beats by rubbing the hammer on the substratum; male-female signals are non-overlapping in the first two species and overlapping in the latter two. Female P. capitata answered with an unusually long sequence of beats. Two male Isoperla species produced monophasic calls without female answers. Female A. lycorias answered taped male signals with monophasic signals like all observed females.

Born to meet the special needs of America`s space effort, the SP-100 Program testifies to the cooperation among government agencies. The Department of Energy (DOE), the National Aeronautics and Space Administration (NASA), and the Defense Advanced Research Projects Agency (DARPA) are working together to produce a 100-kW power system for use in outer space. At this point in the effort, it is appropriate to review: The approach to meet program goals; the status of activities of the Project Office, managed by the Jet Propulsion Laboratory (JPL); and, because this is a meeting on materials, answers beings developed by the Project Office to vital questions on refractory alloy technology.

The original SP-100 conceptual system design was examined from the mechanical design and integration viewpoint for the purpose of updating the design, identifying concerns, and providing recommendations for future work. Some of the findings were that: Integration of heat pipes into the radiator structure appears practical, but a number of problems remain to be addressed and resolved through development effort; thermal and structural interfacing of the shield and defining shield weight are key areas that need to be addressed; the radiator may be critical in shell buckling which would make beryllium a leading candidate material; material problems such as beryllium vs. shuttle fracture mechanics criteria need to be addressed.

DARPA, in conjunction with DOE`s Office of Nuclear Energy, and NASA`s Office of Aeronautics and Space Technology are jointly sponsoring a space nuclear reactor power system program known as the Space Power-100 (SP-100) Development Project. The program is presently in the critical technology phase. This phase, better known as technology assessment and advancement, includes mission requirements definition, system conceptual designs, and critical technology development. A ground test phase decision is scheduled for July 1985. If the decision is positive, the next phase would begin in fiscal year 1986. An overriding concern in conducting this program is to ensure that nuclear safety is being properly addressed even in these early stages.

The objective of this task was to establish and evaluate what PCC technologies need to be developed and what impact the availability and development of PCC technologies will have on Ground Demonstration Development Decision.

From purpose and scope: This report includes a description of the geohydrologic features of the different aquifers; a definition of source, occurrence, movement, and quality of the ground water; and an estimation of the current pumpage and ground-water storage.

Purpose and scope: The U.S. Marine Corps conducts training maneuvers in the study area. Lack of a local source of water has severely limited the utilization of the area. In the past, limited quantities of water have been transported to the area by truck or helicopter. The purpose of this study was to determine the feasibility of obtaining a supply of ground water in the area for use when field maneuvers are being conducted. The major effort for this study was concentrated on the part within the Marine Corps base boundary. The study involved the assessment of ground-water quality, ground water in storage, and aquifer characteristics.

From purpose and scope: The purpose of this part of the Central Valley Aquifer Project is to gather and analyze all available information on the magnitude and distribution of ground-water pumpage in the Central Valley. These data will be used as input to a digital ground-water model, one of the products of the Central Valley Aquifer Project.

Purpose and scope: The purpose of this study was to develop a method for estimating the amount of subsurface return flow to the Colorado River in the Yuma area. This report presents a method that will permit an accounting of ground-water return flows from each side of the Colorado River in the Yuma reach. The estimates of return flow can be used by water-management agencies in determining return-flow credits for the States of Arizona and California.

Abstract: Sacramento County expected to begin operation of the Sacramento Regional Wastewater Treatment Plant in 1982. The California State Water Resources Control Board has ruled that the plant will not be allowed to release effluent into the Sacramento River when flow in the river is 4,000 cubic feet per second or less. Depending on tide condition, flows less than 4,000 cubic feet per second may occur either once or twice during each 24-hour 50-minute tide cycle when the daily mean flow is less than about 12,000 cubic feet per second. Daily mean flows less than 12,000 cubic feet per second occur about 28 percent of the time. Riverflow at the plant outfall is monitored by an acoustic streamflow measuring system. Regulation of effluent released from the plant will normally be based on real-time flow data computed by the acoustic system. A graphical method for determining the occurrence and duration of flows of 4,000 cubic feet per second and less was developed as a backup system to be used if a temporary failure in the acoustic system occurs.

From purpose and scope: The purpose of this study is to describe water-quality conditions in Shasta Lake and in major tributaries to the lake. The study involved the collection and interpretation of historical, hydrologic, and water-quality data collected during intensive and routine monitoring efforts.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 10 P.M.

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 6 P.M.