Computer-acquired performance map of an etched-rhenium, niobium planar diode
Computer acquired performance map of etched-rhenium, niobium planar diode
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Computer acquired performance map of etched-rhenium, niobium planar diode
Vibratory cavitation for metal and superalloy etching in distilled water
Etching aluminum alloys with aqueous solution containing sulfuric acid, hydrofluoric acid, and an alkali metal dischromate for adhesive bonding
Selective plating of etched circuits without removing previous plating
Computer processed performance data for thermionic converter with etched rhenium emitter and niobium collector
Metallographic specimens etching by cavitation damage, testing performance by ultrasonic vibration technique
Spark discharge enhancement of heavy ion track etching in Lexan polycarbonate
Etchant type, concentration and temperature effect on various plastics track etching ratio and sensitivity
Chemically vapor deposited deep etched tungsten emitter for high performance cylindrical thermionic converter
Computer acquired performance mapping of fixed spaced planar diode with etched Re emitter and Nb collector over wide operating temperature range
Technique was developed for fabricating three dimensional pumping grooves on gas bearings by sputter etching. Method eliminates problems such as groove nonuniformity, profile, and finish, which are associated with normal grooving methods.
The effect of collector, guard-ring potential imbalance on the observed collector-current-density J, collector-to-emitter voltage V characteristic was evaluated in a planar, fixed-space, guard-ringed thermionic converter. The J,V characteristic was swept in a period of 15 msec by a variable load. A computerized data acquisition system recorded test parameters. The results indicate minimal distortion of the J,V curve in the power output quadrant for the nominal guard-ring circuit configuration. Considerable distortion, along with a lowering of the ignited-mode striking voltage, was observed for the configuration with the emitter shorted to the guard ring. A limited-range performance map of an etched-rhenium, niobium, planar converter was obtained by using an improved computer program for the data acquisition system.
Performance data from an etched-rhenium, molybdenum thermionic converter are presented. The planar converter has a guard-ringed collector and a fixed spacing of 0.254 mm (10 mils). The data were acquired by using a computer and are available on microfiche as individual or composite parametric current, voltage curves. The parameters are the temperatures of the emitter T sub E, collector T sub C and cesium reservoir T sub R. The composite plots have constant T sub E, and varying T sub C or T sub R, or both. The envelope and composite plots having constant I sub E are presented. The diode was tested at increments between 1500 and 2000 K for the emitter, 750 and 1100 K for the collector, and 540 and 640 K for the reservoir. In all, 774 individual current, voltage curves were obtained.
The results are presented of a glass bead test conducted with a JPL P/N 71 x 12400 etched disk filter assembly to determine the largest diameter spherical glass bead that would transmit through the filter assembly. It was found that the largest glass bead transmitted was 16 microns in diameter.
In one method, fluorescent dye is deposited into tracks of radiograph and viewed under ultraviolet light. In second method, track-etch radiograph is placed between crossed polaroid filters, exposed to diffused light and resulting image is projected onto photographic film.
Martian south polar pits and etched terrain attest to alternating episodes of eolian deposition and erosion. Sometimes the south polar area has served as a sump for the accumulation of airborne debris and associated particles of frozen volatiles. At other times, the wind patterns or wind effectiveness change, and the atmosphere begins to remove the blanket of material it has earlier spread over the south polar region.
The first quarter of a one-year program to investigate the production of patterned etch resistant wax coatings on solar cell substrates by printing is reported. Master molds for printing plates were produced for the plates. The resist wax is being studied to determine its relevant physical properties. A printing device is currently in design, and material costs are being compiled as first step in a cost analysis task. All phases of the project are proceeding according to schedule. No specific phases are yet completed.