development of si3n4 and sic of improved toughness. / for gas turbine engines

the application of energy absorbing surface layers to si3n4 and sic was investigated. among the layers studied were microcracked materials such as iron titanate and a silica-zircon mixture and porous materials such as reaction sintered si3n4. energy absorption due to microcrack extension upon impact was found not to be an important mechan..

precision machining (diamond turning) of optical reflectors

diamond turning is a rapidly developing technology being utilized to produce both large and unique optical reflectors in a cost effective manner. the process is especially suited for the high reflectivity metals such as copper, gold, silver, and aluminum. the basic requirements include a single-crystal diamond tool, a high quality and com..

significance of pesticide residues to human health, / reprint: significance of pesticide residues to human health,

the widespread occurrence in the environment of any foreign chemical is a matter of public health concern. the pesticides are poisons, of course, or they would not be useful in the control of insects, rodents, and other undesirable animals and plants. the possible harmful effect to the general population from intake of small amounts of th..

tactile target alerting system

a close-fitting garment has a pattern of tactile stimulators arranged on its surface. the stimulators can be selectively energized from some remote point in accordance with threats to a person wearing the garment. the stimulators are controlled by a radio receiver fed by a radio transmitter. the relative position of an energized stimulato..

combination spindle-drive system for high precision machining

a combination spindle-drive is provided for fabrication of optical quality surface finishes. both the spindle-and-drive utilize the spindle bearings for support, thereby removing the conventional drive-means bearings as a source of vibration. an airbearing spindle is modified to carry at the drive end a highly conductive cup-shaped rotor ..

development of low-cost, high energy-per-unit-area solar cell modules. quarterly report no. 2

hexagonal solar cell and module efficiencies, module packing ratio, and solar cell design calculations were made. the cell grid structure and interconnection pattern was designed. the module substrate which includes the aluminum pan, aluminum plate, and mounting brackets were designed and fabricated for the three modules to be used in pha..

elastomeric syntactic foams for stress relief of electronic components

elastomeric syntactic foams have been developed for use as stress relief coatings on electronic components in encapsulated electronic assemblies. polysulfide, silicone, and polyurethane elastomers blended with microbubbles made from glass and phenolic resins have all been used to formulate syntactic foams for various applications these fo..

automated array assembly task, phase i. quarterly report

the overall goal of the array automated assembly task, phase i, of the low-cost silicon solar array project is a comprehensive assessment of the processes, conceptual designs, and new technologies required to achieve, by 1985, annual solar cell array production capability greater than 500 megawatts per year at a cost less than $500 per ki..

new portable centrifugal fast analyzer with expanded versatility

developments in solid-state electronics have resulted in the fabrication of a prototype portable instrument with expanded analytical versatility and the capability to operate from 110 v ac or a rechargeable battery pack. the analyzer, contained in an 18 x 11 x 12-in. box and weighing 55 lb, utilizes a self-contained microprocessor to cont..

enzymatic methods of making fructose, and selected other work

this research is devoted to the enzymatic methods of making fructose, a subject of current industrial interest. a wide variety of methods of immobilization of the enzyme have been screened, including containing it in heat-activated cells ('whole' cells), trapping in cellulose acetates, adsorbing on deae cellulose, and covalent bonding to ..