low-temperature photoluminescence of detector-grade hgi sub 2

the low-temperature photoluminescence of hgi sub 2 is reported three main luminescence bands are observed, with peaks at approx 2.30, 2.20, and 2.00 ev at 77 k. at 4.2 k, the highest energy peak shows considerable structure. the temperature dependence of these lines indicates both free and bound exciton recombination, and very small excit..

search for improved surface treatment procedures in fabrication of hgi sub 2 x-ray spectrometers

the influence of various fabrication parameters on the surface quality of hgi sub 2 x-ray spectrometers was studied in detail exposure of etched hgi sub 2 to ambient atmosphere for approx. 24 hours may reduce the electron surface recombination velocity by almost an order of magnitude. reduction of the etching solution temperature (ki in w..

preparation and characteristics of fission chambers with actinide nuclides

fission chambers of parallel-plate type are provided to measure the central fission rates of exp 237 np, exp 238 pu, exp 239 pu, exp 242 pu, exp 241 am, exp 243 am, exp 244 cm and exp 235 u in a series of the cores in fast critical assemblies fca. the chamber consists of the body made of a thin stainless steel wall, the collector of a cir..

recommended paint system for use on ship models

when conducting resistance experiments on ship models in towing tanks, changes in the surface roughness are known to cause changes in the model resistance. in the past several years problems with deteriorating paint surfaces on ship models have resulted in changes in the model resistance. an investigation was undertaken to evaluate existi..

fire blocking systems for aircraft seat cushions

a system for fire blocking in aircraft cushions by minimizing release of flammable gaseous decomposition products is disclosed. the system employs a catalytic matrix which cracks the flammable gaseous decomposition products to less flammable species. the system uses a non-fire retarded polyurethane cushion surrounded by an aramid matrix w..

graphite fiber surface treatment to improve impact strength and fracture resistance in subsequent composites

graphite (or carbon) fiber composite impact strength improvement was attempted by modifying the fiber surface. elastomeric particles were made into lattices and deposited ionically on surface treated graphite fiber in an attempt to prepare a surface containing discrete rubber particles. with hard, nonelastomeric polystyrene discrete parti..

chalcogenide-glass solar cells. quarterly technical report no. 2, january 1, 1980-march 31, 1980

the purpose of the program reported is to determine if several disadvantages of chalcogenide glasses for solar cell applications can be overcome by chemical modification. these problems include a pinned fermi energy, low carrier lifetime, and the presence of geminate recombination for photon frequencies just above the optical bandgap whic..

ultrasonic weld bonding of helicopter primary structures

this program was a study to develop and optimize an ultrasonic weld bonding procedure for the fabrication of primary structural components for helicopters. this procedure, a combination of ultrasonic welding and adhesive bonding, was studied through a series of coupon tests. various adhesives and surface treatments were evaluated with reg..

microwave heating: industrial applications. 1970-january 1983 (citations from the engineering index data base)

industrialized uses of microwave heating are covered in these citations of worldwide research. the topics include industrial heating and drying for processes such as paper drying, vulcanization, and textile processing. equipment design and safety are also cited (this updated bibliography contains 278 citations, 30 of which are new entries..

further development of a low-cost solar panel. final report, september 30, 1980-march 30, 1982

the low-cost solar panel (lcsp) is a liquid-heating flat-plate collector fabricated with thin polymer films in high-speed production processes. the primary objective of the work reported was to concentrate on the materials requirements and to work toward commercialization of the lcsp concept. tasks included a rigorous material search, sur..