ENERGY MAY 1974 A Continuing Bibliography (Suppl. 01) A74-10144 The technology and economics of commercial airplane design. I. J. E. Steiner (Boeing Co., Commercial Airplane Group, Renton, Wash.). Esso Air World, vol. 25, no. 5, 1973, p. 119-124. Discussion of the relation between technology and economics in commercial aviation. Past and present priority orders of aircraft market requirements in speed, range, frequency, quietness, passenger comfort and economics are compared. Direct operating cost trends, aerodynamic efficiency trends, thrust-to-weight growth, engine fuel efficiency trends, payload efficiency, airline revenues vs passenger yield, progress in takeoff noise reduction, return on investment, and approach noise are covered. Improved technology, two-man crew, reduced block time and maintenance cost, and communality/ facilities compatibility are listed as elements of improved commercial aircraft design economics. V.Z. A74-10463 # Heating of a substance by an arc plasma (Plazmenno-dugovoi nagrev veshchestva). A. V. Nikolaev. In: Plasma processes in metallurgy and in the technology of inorganic materials. Moscow, Izdatel'stvo Nauka, 1973, p. 20-32. 21 refs. In Russian. The energetic characteristics of the heating process are analyzed for the heating of the vaporized and condensed phases of substances within and outside the electrical field of an arc discharge. It is shown that the heating of substances by an arc discharge plasma has a potential as a technique for practical electric-to-thermal energy conversion. It is also found that the power delivered to the substance can be controlled within large limits by varying the electrical parameters of the arc and the thermophysical properties of the plasma arc gas when this electric-to-thermal energy conversion process is used. An efficiency in excess of 80% is indicated for this energy conversion method. V.Z. A74-10691 # Physical behaviour of some biowaste gases in an ion engine. A. R. Martin (City University, London, England). American Institute of Aeronautics and Astronautics, Electric Propulsion Conference, 10th, Lake Tahoe, Nev., Oct. 31-Nov. 2, 1973, Paper 73-1113. 7 p. 12 refs. Members, $1.50; nonmembers, $2.00. Research supported by the Science Research Council and Department of Trade and Industry. The operation of a 100 mm diameter electron-bombardment ion engine using carbon dioxide, methane and nitrogen propellants was studied. The engine was of modern configurational design, but constructed to laboratory requirements rather than flight or engineering standards. The operation with nitrogen and methane was quite similar, and resulted in stable operation with reasonable efficiencies. Operation with carbon dioxide was anomalous, in that as utilization was increased a point occurred where the losses rose and the beam current fell. This was thought to be related to a change in the cathode work function as a result of oxygen poisioning. (Author) A74-11020 # Satellite solar power stations to meet future energy demands. P. E. Glaser (Arthur D. Little, Inc., Cambridge, Mass.). Industries Atomiques et Spatiales, vol. 17, July-Aug. 1973, p. 77-95. 16 refs. In English and French. A satellite solar power system (SSPS) can be designed to generate electrical power on earth at specific levels ranging from about 3000 to 15,000 megawatt. Over this range of power output the orbiting portion of the SSPS exhibits the best power-to-weight characteristics. Additional solar collector arrays and antennas could be added to establish an SSPS system at a desired orbital location. With the receiving antenna placed either on land or on platforms over water near major load centers and tied into a power transmission grid, power could be delivered to almost any desired geographic location. F.R.L. A74-11219 # Gas generators - A perspective. W. H. Cutler (Lockheed Missiles and Space Co., Inc., Sunnyvale, Calif.). American Institute of Aeronautics and Astronautics and Society of Automotive Engineers, Propulsion Conference, 9th, Las Vegas, Nev., Nov. 5-7, 1973, AIAA Paper 73-1168. 7 p. Members, $1.50; nonmembers, $2.00. The gas generator is usually thought of as a light weight, high power, short duration energy source, used mainly in aircraft and missiles. This premise is re-examined by viewing gas generators in the perspective of other energy sources with similar or overlapping characteristics and applications, to see where gas generators have a performance edge and where gaps exist which are opportunities for new gas generator applications. The alternative energy sources, which in addition to gas generators include gas turbines, reciprocating engines, compressed gas containers and hydraulic accumulators, flywheels, batteries, fuel cells, and solar photovoltaic cells, are first described in terms of their energy conversion process and the form in which their output energy is delivered. They are then compared on the basis of stored energy density and applicable power levels. Next, the factors involved in matching an energy source to its operating environment are enumerated. Finally, a number of new applications for gas generators are suggested which introduce new requirements in both technical and marketing areas. (Author) A74-11257 # Solid state hydrogen gas generator. W. H. Barber, W. F. Beckert, and O. H. Dengel (U.S. Navy, Naval Ordnance Station, Indian Head, Md.). American Institute of Aeronautics and Astronautics and Society of Automotive Engineers, Propulsion Conference, 9th, Las Vegas, Nev., Nov. 5-7, 1973, AIAA Paper 73-1232. 4 p. Members, $1.50; nonmembers, $2.00. A family of light-weight solid state hydrogen gas generators has been developed for inflation of rocket deployed balloon structures. The generators utilize a reaction between metal hydrides and ammonium halides. The chemical reaction is thermally initiated. The generators tested so far are capable of inflating 1-15 cu. ft. structures at STP. The development of solid state hydrogen gas generators for inflation of 1,000-100,000 cu. ft. balloon structures appears feasible. (Author) A74-11315 # The case for hydrogen fueled transport aircraft. G. D. Brewer (Lockheed-California Co., Burbank, Calif.). American Institute of Aeronautics and Astronautics and Society of Automotive Engineers, Propulsion Conference, 9th, Las Vegas, Nev., Nov. 5-7, 1973, AIAA Paper 73-1323. 13 p. 14 refs. Members, $1.50; nonmembers, $2.00. Arguments in favor of the substitution of liquid hydrogen for oil to power commercial aircraft are presented. Shortage of petroleum in the United States and the need for import will lead to unacceptable dependence on foreign nations, will cost the U.S. heavily in terms of deficit balance of payments, and can become a continuous threat of interruption of oi! supply that will endanger our independence in the fields of commerce, world trade, diplomacy, and even our national security. In addition, hydrogen offers potential advantages when used in aircraft. Examples of subsonic and supersonic commercial aircraft are examined to determine the advantages in performance, pollution, noise, and cost. Some problems associated with the use of V.P. liquid hydrogen as a fuel are discussed. A74-12201 Spacecraft electrical power. E. Stofel (Hughes Aircraft Co., El Segundo, Calif.). In: EASCON '73; Electronics and Aerospace Systems Convention, Washington, D.C., September 17-19, 1973, Record. New York, Institute of Electrical and Electronics Engineers, Inc., 1973, p. 225-231. 13 refs. Present developments in spacecraft power systems are placing strong emphasis on component weight reduction and efficiency improvements as a means of obtaining spacecraft with more power. The most striking of these are: (1) the improved efficiency of solar cells; (2) light-weight, large area solar arrays; (3) the possibility of light-weight nickel-hydrogen energy storage units; and (4) restructuring of power control electronics at higher operating voltages. These developments will tend to encourage further use of solar cell power systems for increasingly larger spacecraft, a trend that is already well established by the use of solar cells on almost all past and present spacecraft. Nuclear powered systems are advancing at a slower rate, with limited funding, and, therefore, apparently will remain relegated to special situations, such as missions to the outer planets or where physical compactness is a distinctive requirement. (Author) A74-12242 # High voltage solar cell power generating system for regulated solar array development. E. Levy, Jr. (Hughes Aircraft Co., Los Angeles, Calif.) and A. C. Hoffman (NASA, Lewis Research Center, Cleveland, Ohio). American Institute of Aeronautics and Astronautics, Electric Propulsion Conference, 10th, Lake Tahoe, Nev., Oct 31-Nov. 2, 1973, Paper 73-1105. 13 p. Members, $1.50; nonmembers, $2.00. Contract No. NAS3-15826. A laboratory solar power system regulated by on panel switches has been delivered for operating high power (3 kw), high voltage (15,000 volt) loads (communication tubes, ion thrusters). The modular system consists of 26 solar arrays, each with an integral light source and cooling system. A typical array contains 2560 seriesconnected cells. Each light source consists of twenty 500 watt tungsten iodide lamps providing plus or minus 5 per cent uniformity at one solar constant. An array temperature of less than 40 C is achieved using an infrared filter, a water cooled plate, a vacuum hold-down system, and air flushing. (Author) A74-12794 # Actual state of French technical developments concerning sources of space power (Etat actuel des développements techniques français en matière de sources de puissance spatiales). W. Palz and C. Martin (Centre National d'Etudes Spatiales, Paris, France). International Astronautical Federation, International Astronautical Congress, 24th, Baku, Azerbaidzhan SSR, Oct. 7-13, 1973, Paper. 17 p. 6 refs. In French. French progress in study and research concerning solar generators for space applications is described. On the level of components continuing effort is being put forth to perfect silicon cells. The development of thin-film cadmium sulfide cells has reached the stage of practicality. In the years to come complete commercial production is expected. Rigid and flexible structures of solar panels have been developed in the 100 W to 10 kW range. Research and development work in this field is reviewed. F.R.L. A74-12905* # Industrial use of aerospace technology. J. E. Burnett (NASA, Lewis Research Center, Cleveland, Ohio). International Astronautical Federation, International Astronautical Congress, 24th, Baku, Azerbaidzhan SSR, Oct. 7-13, 1973, Paper. 5 p. Using a few selected examples of the several hundred successful transfers of aerospace technology to applications outside the aerospace field, it is shown that aerospace-related new technology does have many valuable nonaerospace uses. The examples presented include technology transfers to the machine tool and petroleum industries as well as to the fields of electric utilities and computeraided structure design. M.V.E. A74-13234 # Satellite nuclear power station: An engineering analysis. J. R. Williams, J. D. Clement (Georgia Institute of Technology, Atlanta, Ga.), R. J. Rosa, K. D. Kirby, and Y. Y. Yang, Research supported by NASA; Grant No. NGR-11-002-145. Atlanta, Ga., J.R. Williams, Georgia Institute of Technology, 1973. 143 p. 41 refs. A nuclear-MHD power plant system which uses a compact non-breeder reactor to produce power in the multimegawatt range is analyzed. It is shown that, operated in synchronous orbit, the plant would transmit power safely to the ground by a microwave beam. Fuel reprocessing would take place in space, and no radioactive material would be returned to earth. Even the effect of a disastrous accident would have negligible effect on earth. A hydrogen moderated gas core reactor, or a colloid-core, or NERVA type reactor could also be used. The system is shown to approach closely the ideal V.P. of economical power without pollution. A74-13293 # Conversion of fuel nitrogen to NOx in a compact combustor. H. R. Hazard (Battelle Columbus Laboratories, Columbus, Ohio). American Society of Mechanical Engineers, Winter Annual Meeting, Detroit, Mich., Nov. 11-15, 1973, Paper 73WA/GT-2. 4 p. Members, $1.00; nonmembers, $3.00. A low-nitrogen fuel, ASTM Jet A aviation kerosene, was doped with increasing amounts of pyridine as a means of increasing the content of chemically bound nitrogen; it was then burned at a rate of 50 lb/hr in a compact combustor incorporating staged air admission with a rich primary zone and water cooling of the walls. Each increase in fuel nitrogen content resulted in a significant increase in NOx in the combustion products, and it is estimated that as much as 90% of the fuel nitrogen was converted to NOx at very low nitrogen levels, decreasing to 55% conversion at higher levels. These results are consistent with data reported for large steam boilers and for small residential boilers. It appears that emission standards requiring very low levels of NOx emission will require use of fuels with very low nitrogen content. (Author) July-Aug. 1973, p. 37-44. In French. Consideration of the technology and characteristics of various types of thermoelectric flame generators, and review of the design of power plants employing such generators. A detailed description is given of the thermoelectric modules, the combustion chamber, and the heat exchangers employed in a thermoelectric flame generator, and various possible applications of these generators are noted, with particular emphasis placed on their use as power supplies for a radio beam relay station. It is concluded that currently used thermoelectric flame generators are well adapted to user needs, and are reliable and competitive with energy sources such as solar cells or high-capacity chemical batteries. A.B.K. A74-13559 Effect of the sun, the moon and solar radiation pressure on a near-equatorial synchronous satellite. C.-H. Zee (Grumman Aerospace Corp., Bethpage, N.Y.). Astronautica Acta, vol. 18, Oct. 1973, p. 281-287. 9 refs. Research sponsored by the Grumman Aerospace Corp. The effect of the sun, the moon and solar radiation pressure on a near-equatorial synchronous satellite is investigated by an extension of the previous work on the effect of the sun and the moon. In addition to the orbital plane movement mainly due to the sun and the moon, the solar radiation pressure results in the change of eccentricity as well as the rotation of the line of apsides. However, an integrated solution is presented to show the coupled effect of all orbital elements. (Author) A74-13798 Performance and noise aspects of supersonic transport. J. Calmon and R. Hoch (SNECMA, Paris, France). In: INTER-NOISE 73; Proceedings of the International Conference on Noise Control Engineering. Copenhagen, Denmark, August 22-24, 1973. Lyngby, INTER-NOISE 73, Danmarks Tekniske Hojskole, 1973, p. 464-473. 5 refs. The operating economics of a supersonic commercial aircraft are shown to be very sensitive to changes in power plant weight and propulsion efficiency and, therefore, necessarily compelled to be noisier than subsonic aircraft at the same technology level. It is expected that the noise level of supersonic commercial aircraft will be governed by the capability of varying optimal aerodynamic and propulsive configurations between takeoff and cruise. M.V.E. of the generator length and the load factor. The influence of the channel shape and the inlet Mach number on the conversion factor is examined, and the range of optimal parameters is determined. The energy conversion efficiency of a Faraday-type generator with solid electrodes is discussed. V.P. A74-14043 Cryogenic Engineering Conference, University of Colorado, Boulder, Colo., August 9-11, 1972, Proceedings. Conference sponsored by the National Academy of Sciences, National Bureau of Standards, et al. Edited by K. D. Timmerhaus (Colorado, University, Boulder, Colo.; National Science Foundation, Engineering Div., Washington, D.C.). New York, Plenum Press (Advances in Cryogenic Engineering. Volume 18), 1973. 544 p. $30. Recent developments in various aspects of low-temperature technology are reviewed in papers dealing with cryogenic processes, equipment, instrumentation, properties, and applications. General areas covered include liquefied natural gas technology, heat transfer measurements, insulation systems, cryogenic fluid mechanics, mechanical properties of structural materials used in cryogenic systems, determination of the thermodynamic properties of cryogenic fluids, thermal properties of nylons and greases, cryogenic instrumentation systems, refrigeration equipment, practical applications of superconductivity, and the preparation of atomic and metallic hydrogen. T.M. A74-14046 # Development program for a liquid methane heat pipe. W. G. Foster and D. O. Murray (Lockheed Research Laboratories, Palo Alto, Calif.). In: Cryogenic Engineering Conference, Boulder, Colo., August 9-11, 1972, Proceedings. New York, Plenum Press, 1973, p. 96-102. 8 refs. Description of a development program on the design of a heat pipe which would transfer 2 W of power over a length of 122 cm, with a total temperature drop of 2 K and a condenser temperature of 110 K. The heat pipe is intended for spacecraft applications, and the design requirements were satisfied by a simple wire-cloth wick, using methane as the working fluid. Thermal tests in a one-g field were conducted, and results agreed closely with the predicted performance. The radial temperature gradient was found to be smaller than anticipated for a methane heat pipe. No degradation in performance was found after the prototype was subjected to launch environment T.M. tests. A74-13943 Optimization of the power of Faraday MHD generators operating on nonequilibrium plasma. V. S. Vorob'ev and V. I. Krasnov (Akademiia Nauk SSSR, Nauchno-Issledovatel'skii Institut Vysokikh Temperatur, Moscow, USSR). (Teplofizika Vy. sokikh Temperatur, vol. 11, Jan. Feb. 1973, p. 161-166.) High Temperature, vol. 11, no. 1, Sept. 1973, p. 134-138. 6 refs. Translation. The electric output power of a Faraday-type MHD-generator using an inequilibrium turbulent plasma as the working medium is optimized under the assumption that the damping parameters of the gas at the channel inlet, the magnetic fiux density, and the length and maximum cross section of the channel are known. Expressions relating the optimal local parameters are derived, and a system of equations describing the optimal flow is solved numerically. Calculations for a helium-cesium mixture are performed as an example. V.P. A74-13944 Qualitative analysis of the efficiency of MHD energy conversion. V. Iu. Baranov, D. D. Maliuta, V. P. Panchenko, and F. R. Ulinich (Akademiia Nauk SSSR, Institut Atomnoi Energii, Moscow, USSR). (Teplofizika Vysokikh Temperatur, vol. 11, Jan.Feb. 1973, p. 167-173.) High Temperature, vol. 11, no. 1, Sept. 1973, p. 139-144. Translation. A method is proposed for solving the system of one-dimensional differential equations describing the gas flow in the channel of a Faraday-type MHD generator with ideally segmented electrodes. The convergence efficiency of the generator is determined as a function A74-14057 # Cryogenic instrumentation at and above liquid hydrogen temperature Present and future. W. E. Keller (California, University, Los Alamos, N. Mex.). In: Cryogenic Engineering Conference, Boulder, Colo., August 9-11, 1972, Proceedings. New York, Plenum Press, 1973, p. 289-300. 18 refs. AEC-sponsored research. Discussion of instrumentation problems associated with present and possible future large-scale cryogenic systems operating at or above liquid hydrogen temperatures i.e., at temperatures above 13.8 K. Emphasis is placed on energy applications involving the use of liquid oxygen, liquid hydrogen, and liquefied natural gas as fuels and refrigerants. The types of processes and information which may be required in order to operate and regulate such large-scale cryogenic systems are outlined together with presently available and anticipated types of instrumentation required to meet operational demands. Attention is given to liquefaction and refrigeration systems, dewar insulation, liquid level sensors, measurement of state T.M. properties, and special storage methods. Consideration of the feasibility of setting up an orbiting solar reflector and orbiting space power generation and distribution plants. A system called Lunetta, designed for practically useful night illumination of areas of the earth's surface by a reflector in equatorial geosynchronous orbit, is described. The socio-economic value of the Lunetta is stressed by citing the possibility of conducting agricultural activities with its aid at night. Problems connected with the choice of the size, location, and brightness of Lunetta are discussed, as well as problems of weight minimization and radiation-pressure compensation. The possibility of large-scale power generation in space, using nuclear, solar-thermal, and photovoltaic-reflector systems, is considered, as well as a power relay concept involving large antennas in geosynchronous orbit, reflecting and redirecting the energy flow of microwave beams. The ability of the Integrated Space Shuttle configuration selected by NASA and the Geospace Interorbital Transportation vehicle (incorporated in the Shuttle payload and then released in low orbit) to assist in the construction of large installations in geosynchronous orbit is evaluated. A.B.K. Hollywood, Calif., Western Periodicals Co., 1973, p. 25/2-1 to 25/2-4. The FAA is currently installing solid-state uninterruptible power source (UPS) equipment to supply electrical power at a high level of reliability in 20 U.S. air route traffic control centers. Each UPS consists of several parallel-connected 200-kVA rectifier-inverter modules which operate either from the commercial power line or from batteries and engine-generator sets upon failure of the commercial power. Performance and reliability requirements dictated by application in the air route traffic control centers are outlined together with plans developed for testing and maintenance of these power units. T.M. A74-14248 Chemical storage of hydrogen in Ni/H2 cells. M. W. Earl and J. D. Dunlop (COMSAT Laboratories, Clarksburg, Md.). COMSAT Technical Review, vol. 3, Fall 1973, p. 437-441. 5 refs. Research sponsored by the International Telecommunications Satellite Organization. It is shown that LaNi5 hydride can be used to reduce the operating pressure of a nickel/hydrogen cell without affecting its high cycle-life expectancy. Advantages of this concept are: safe operation at high hydrogen pressures, cell volume reduction of almost 50%, and simplification of cell pressure vessel design through prismatic-type cell construction; this eliminates electrolyte loss problems, provides an electrode stack design with improved shock and vibration characteristics, and simplifies battery packaging. V.P. A74-14250 Vitreous oxide antireflection films in highefficiency solar cells. A. G. Revesz (Communications Satellite Corp., Washington, D.C.). COMSAT Technical Review, vol. 3, Fall 1973, p. 449-452. 7 refs. Lindmayer and Allison (1973) have shown that the short wavelength response and the fill factor of silicon solar cells can be significantly improved by using a major modification of the grid geometry in combination with a very shallow junction and a new antireflection film. The new cell, termed the violet cell, has a conversion efficiency of 13 to 14 percent. The theoretical considera tions on which the antireflection film is based are outlined, and test data are examined. V.P. A74-14327 A qualitative description of thermionic converters is given and basic phenomena in thermionic conversion are considered together with types of thermionic converters, the characteristics of typical thermionic converters, thermionic-converter systems, and aspects of thermionic conversion with other electrical power systems. Questions regarding the ideal performance of diode thermionic converters are examined, giving attention to thermionic emission, a simple diode thermionic converter, electron-motive diagrams through the interelectrode space, output-current characteristics, energy-conversion efficiency, and optimum ideal performance. Vacuum thermionic converters are described along with vapor thermionic converters. A74-14463 G.R. The second fifteen years in space; Proceedings of the Eleventh Goddard Memorial Symposium, Washington, D.C., March 8, 9, 1973. Symposium sponsored by the American Astronautical Society. Edited by S. Ferdman (Grumman Aerospace Corp.. Bethpage, N.Y.). Tarzana, Calif., American Astronautical Society (Science and Technology Series. Volume 31), 1973. 196 p. $15. The forthcoming fifteen years of U.S. efforts in space are examined in papers dealing with the impact of the space program on industrial, scientific, and social aspects of life in the U.S. Attention is given to anticipated developments in rocket engines, the possibility of harnessing solar energy as a source of electric power on earth by means of satellites, the use of computer control systems in manned and automated space vehicles, and the growth of the data communications technology. Exploration of the terrestrial planets is considered in a description of the Viking mission to Mars, and aspects of international cooperation in space are examined together with European space projects after 1980. With increasing attention focusing on the energy problem, considerable interest has recently surfaced relative to the potential use of solar energy as a power source for our nation. This paper assesses the possibilities for near-term and longer-range applications of solar energy, including a large space-based Satellite Solar Power Station. Many applications are well beyond the research phase and could be accelerated to commercial readiness. Longer-range applications should be pursued with appropriate technology development programs to provide this nation with energy options in the future. If the nation wants to use solar energy as a major power source, it is technically possible to do so. Further, with appropriate incentives and government support, the public can have this clean and abundant energy source economically. (Author) A74-14892 * Quantification of the luminescence intensity of natural materials. R. D. Watson, T. D. Hessin (U.S. Geological Survey, Denver, Colo.), and W. R. Hemphill (U.S. Geological Survey, Washington, D.C.). In: Management and utilization of remote sensing data; Proceedings of the Symposium, Sioux Falls, S. Dak., October 29-November 1, 1973. Falls Church, Va., American Society of Photogrammetry, 1973, p. 364-376. 7 refs. NASA-supported research. NASA Order L-58514. Review of some of the results of an evaluation of the use of an airborne Fraunhofer line discriminator (FLD) for the detection of sun-stimulated luminescence emitted by rhodamine WT dye and some other materials. Rhodamine dye is reported to have been detected by airborne FDL in sea water in concentrations of less than 2 ppb. Experiments with a fluorescence spectrometer in the laboratory indicate that luminescence of some samples of crude and refined petroleum exceeds the luminescence intensity of rhodamine dye in concentrations of 10 ppm. M.V.E. A74-16116 Regional and global energy transfer via passive power relay satellites. K. A. Ehricke (Rockwell International Corp., Space Div., Downey, Calif.). In: Technology today and tomorrow; Proceedings of the Tenth Space Congress, Cocoa Beach, Fla., April 11-13, 1973. Cape Canaveral, Fla., Canaveral Council of Technical Societies, 1973, p. 5-15 to 5-94. 23 refs. The Power Relay Satellite (PRS) offers interesting possibilities as a feasible, shuttle-compatible method of transferring energy over continental or global distances. The basic principle of the PRS is that a microwave reflector is placed into geosynchronous orbit to redirect energy beamed from a power generation system (power source) to a receiver at a great distance from the power source. There the microwave energy is converted back to electricity for local distribution. Particulars of the transmitter antenna are given. The technology of converting electricity to microwave power was advanced greatly with the development of crossed-field devices. They operate on the principle of electron motion in a crossed electric and magnetic field. Microwave beam transmission is examined. Energy sources and primary electric power plants (PEPPs) in the United States are discussed. Attention is given to the shuttle compatibility of space relaying and its comparison with space power generation. F.R.L. A74-16123 * Cape Canaveral, Fla., Canaveral Council of Technical Societies, 1973, p. 7-19 to 7-26. 7 refs. NASA, at the request of the AEC, is conducting a preliminary study to determine the feasibility of disposing of nuclear waste material into space. The study has indicated that the Space Shuttle together with expendable and nonexpendable orbital stages such as the Space Tug or Centaur can safety dispose of waste material by ejecting it from the solar system. The safety problems associated with all phases of launching and operation (normal, emergency and accident) of such a system are being examined. From the preliminary study it appears that solutions can be found that should make the risks acceptable when compared to the benefits to be obtained from the disposal of the nuclear waste. A74-16909 (Author) Evolution of studies in the field of gas lasers (Evolution des recherches dans le domaine des lasers à gaz). J. Robieux (Compagnie Générale d'Electricité, Marcoussis, Essonne, France). (Société Française de Physique, Congrès, Vittel, France, May 28-June 2, 1973.) Journal de Physique, vol. 34, Nov.-Dec. 1973, Supplement, p. C2-81 to C2-103. In French. Research supported by the Direction des Recherches et Moyens d'Essais, and Commissariat à l'Energie Atomique. The progress of research in the field of gas lasers in the last five years is assessed, and a tentative prediction of what the evolution might be in the years to come is offered. The main objectives of work in this area are, first, obtaining the high laser energies in short time durations needed for the feasibility studies of laser induced nuclear fusion and second, investigating the physical principles that can be used to make laser sources capable of delivering high average powers. The physical phenomena that control the operation of presently existing laser devices are now sufficiently understood so that it is possible to predict that a new generation of lasers could be designed in the future, operating in the UV or possibly the X ray region of the spectrum. F.R.L. A74-17195 # Recent developments in the field of thermionic power conversion and its possible effects on power supply systems in space and on earth (Neuere Entwicklungen auf dem Gebiet der thermionischen Energiewandlung und deren mögliche Auswirkungen auf Energieversorgungssysteme im Weltraum und auf der Erde). R. Henne (Deutsche Forschungs- und Versuchsanstalt für Luft- und Raumfahrt, Institut für Energiewandlung und elektrische Antriebe, Stuttgart, West Germany). Österreichische Gesellschaft für Weltraumforschung und Flugkörpertechnik and Deutsche Gesellschaft für Luft- und Raumfahrt, Gemeinsame Jahrestagung, 6th, Innsbruck, Austria, Sept. 24-28, 1973, DGLR Paper 73-092, 13 p. In German. A74-17204 # Technological problems with large-area solar cell arrays (Technologische Probleme bei grossflächigen Solargeneratoren). N. Römisch (Gesellschaft für Weltraumforschung mbH, Porz-Wahn, West Germany). Österreichische Gesellschaft für Weltraumforschung und Flugkörpertechnik and Deutsche Gesellschaft für Luft- und Raumfahrt, Gemeinsame Jahrestagung, 6th, Innsbruck, Austria, Sept. 24-28, 1973, DGLR Paper 73-107. 26 p. 11 refs. In German. Comparative study of two proposed solar cell array concepts with respect to their design, testing, launching, and operation. The two concepts considered are, respectively, a collapsible semirigid array and a flexible rollout array. A detailed study is made of launch vehicle constraints on weight and storage volume in the two concepts, the effects of reaction forces resulting from extension of the solar array on orbital and attitude control of the satellite are assessed, and an analysis is made of the heat-transfer and powergenerating capabilities of the two concepts. A.B.K. A74-17296 # Photosensitive elements for solar sensors (Eléments photo-sensibles pour senseurs solaires). Y. Salles (Radiotechnique-Compelec, Caen, France). Industries Atomiques et Spatiales, vol. 17, Sept. Oct. 1973, p. 41-46. In French. Spacecraft stability and attitude control is usually obtained through solar sensors with silicon transistors. Three types of solar cells are described: by focusing, by angle of attack, and digital, the latter being explained in detail. The selection of the silicon chip, the technology and the assembly of the transistors, and applications to the satellite Symphonie are discussed. N.D. A74-17439 Characteristics of a nonequilibrium MHD generator. A. E. Buznikov, V. E. Vanin, and V. V. Kirillov (Akademiia Nauk SSSR, Nauchno-Issledovatel'skii Institut Vysokikh Temperatur, Moscow, USSR). (Teplofizika Vysokikh Temperatur, vol. 11, May-June 1973, p. 622-631.) High Temperature, vol. 11, no. 3, Jan. 1974, p. 554-561. 23 refs. Translation. Results of experimental studies of a nonequilibrium MHD generator operating with a potassium-seeded argon plasma. Test measurements were performed at Hall numbers ranging from 1.5 to 25, electron temperatures of 1800 to 2800 K, electron-to-neutral particle temperature ratios of 1.1 to 1.8, and various values of relative wall temperature. It is shown that in addition to the influence of ionizational instability, the characteristics of a non |