evaluation of cvd silicon carbide for synchrotron radiation mirrors

chemical vapor deposited silicon carbide (cvd sic) is a recent addition to the list of materials suitable for use in the harsh environment of synchrotron radiation (sr) beam lines. sr mirrors for use at normal incidence must be ultrahigh vacuum compatible, must withstand intense x-ray irradiation without surface damage, must be capable of..

enzymatic tranformations of lignin

research is summarized on biological approaches to the utilization of lignin degradation to raw material for the manufacture of chemicals and materials. this investigation studied the possible involvement of reduced oxygen species produced by the white-rot fungus, c. versicolor, in the initial breakdown of the lignin macromolecule during ..

a conceptual design study of point focusing thin-film solar concentrators

candidates for reflector panel design concepts, including materials and configurations, were identified. the large list of candidates was screened and reduced to the five most promising ones. cost and technical factors were used in making the final choices for the panel conceptual design, which was a stiffened steel skin substrate with a ..

low-cost epitaxial techniques for solar-cell fabrication. quarterly technical progress report no. 3, 25 march-24 june 1980

during the third quarter, the practical aspects of making epitaxial solar cells were emphasized by exploring the growth and fabrication of large-area cells. in this work, a significant achievement was the attainment of efficiencies close to 10 with epitaxial cells of 10.8 cm exp 2 area grown on the lowest grade silicon substrate under stu..

quality engineering and control. semiannual progress report, november-december 1978, january-april 1979

this document reports the following: atomic absorption spectroscopy of ir in pu-ir alloys; removal of pu from soil; surface microanalysis using elemental x-ray mapping; microscopic scanning of ga in pu; microscopy of defects in pu; emission spectroscopy of ir and y in puo sub 2 ; gas chromatograhy of pcb's in transformer oils and water; l..

aging and corrosion problems with flat solar energy absorbers. study based upon literature and experiment exchanges aaldrings-och korrosions-problem hos plana termiska solfaangare. en studie baserad paa litteratur och erfarenhetsutbyte

the construction and the causes of damage to solar energy absorbers are reviewed. aging is due to ultraviolet radiation, temperature, humidity, oxygen, impurities in the air and other effects. a literature review is given about the constituent parts. the coverplate may be of glass, several types of plastics, fluoro-compounds, fiberglass, ..

measurement of surface recombination velocity for silicon solar cells using a scanning electron microscope with pulsed beam

the role of surface recombination velocity in the design and fabrication of silicon solar cells is discussed. a scanning electron microscope with pulsed electron beam was used to measure this parameter of silicon surfaces. it is shown that the surface recombination velocity, s, increases by an order of magnitude when an etched surface deg..

pipeline system insulation: thermal insulation and corrosion prevention. 1976-january, 1982 (citations from the rubber and plastics research association data base)

this bibliography cites reports concerned with thermal and corrosion insulating of pipeline systems used to transfer a variety of substances. thermal aging of polyurethane foam for insulating heating pipes, extrusion film pipeline insulation materials and processes, flexible expanded nitrile rubber pipeline insulation with class 1 fire ra..

fabrication of small precision parts: a study explores 25 problem areas confronting the manufacturers of miniature precision mechanisms

this citation summarizes a one-page announcement of technology available for utilization. a recent report summarizes tests and 7 years of fabrication experience of 25 different aspects of manufacturing miniature metal, plastic, and ceramic parts capabilities and limitations are examined in such areas as small-hole drilling and tapping, th..

biomedical technology transfer. applications of nasa science and technology

ongoing projects described address: (1) intracranial pressure monitoring; (2) versatile portable speech prosthesis; (3) cardiovascular magnetic measurements; (4) improved emg biotelemetry for pediatrics; (5) ultrasonic kidney stone disintegration; (6) pediatric roentgen densitometry; (7) x-ray spatial frequency multiplexing; (8) mechanica..