On the similarity of plasma-polymerized tetrafluoroethylene and RF plasma-sputtered polytetrafluoroethylene
No abstract available
NASA Discipline Environmental Health↗
Engineering topics
Johnson, A. L.
Publications and source records attributed to Johnson, A. L..
Spacecraft-borne long life cryogenic refrigeration: Status and trends
The status of cryogenic refrigerator development intended for, or possibly applicable to, long life spacecraft-borne application is reviewed. Based on these efforts, the general development trends are identified. Using currently projected technology needs, the various trends are compared and evaluated. The linear drive, non-contacting bearing Stirling cycle refrigerator concept appears to be the best current approach that will meet the technology projection requirements for spacecraft-borne cryogenic refrigerators. However, a multiply redundant set of lightweight, moderate life, moderate reliability Stirling cycle cryogenic refrigerators using high-speed linear drive and sliding contact bearings may possibly suffice.
Johnson, A. L.↗
Rugged microelectronic module package supports circuitry on heat sink
Rugged module package for thin film hybrid microcircuits incorporated a rigid, thermally conductive support structure, which serves as a heat sink, and a lead wire block in which T-shaped electrical connectors are potted. It protects the circuitry from shock and vibration loads, dissipates internal heat, and simplifies electrical connections between adjacent modules.
Johnson, A. L.↗