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At least 127 records · Page 7

Noise diffraction patterns eliminated in coherent optical systems

Lens rotation technique of noise diffraction pattern elimination spreads diffracted energy, normally concentrated over small area of image, over much larger annular area. Technique advantages include simplified lens selecting process, reduced clean room requirements, and low cost equipment requirements.

Grebowsky, G. R.↗

Portable superclean air column device Patent

Portable apparatus producing high velocity annular air column surrounding low velocity, filtered, superclean air central core for industrial clean room environmental control

Kiszko, W.↗

Experimental system for the control of surgically induced infections

The results are presented of the development tests performed on the experimental system for the control of surgically induced infections. Tests were performed on the portable clean room to demonstrate assembly, collapsability, portability and storage. Collapsing, relocating and storing within the surgery room can be accomplished in 12 minutes. The storage envelope dimensions are 1.64 m x 4.24 m x 2.62 m high. The disassembly transfer to another room, and reassembly were demonstrated. The laminar air flow velocity profile within the enclosure was measured. In the undisturbed area of the enclosure the air flow met the Federal Standard 209a requirements of 27.45 meters per minute + or - 6.10 meters per minute. Smoke tests with simulated surgery equipment and personnel in the enclosure did not indicate any detrimental air flow patterns. It is concluded that the system as designed will perform the functions required for its intended use.

Source record↗

Experimental system for the control of surgically induced infections

The development tests to be performed on the experimental system are described in detail. The test equipment, conditions, and procedures are given. The portable clean room tests include assembly, collapsability, portability, and storage; laminar flow rate; static pressure; air flow pattern; and electrostatic buildup. The other tests are on the ventilation system, human factors evaluation, electrical subsystem, and material compatibility.

Tevebaugh, M. D.↗

Aerospace technology and hospital systems

The use of aerospace medical techniques to improve the quality of earth health care systems is discussed. Data are focused on physiological measurements and monitoring, medical information management, clean room technology, and reliability and quality assurance for hospital equipment.

Source record↗

Experimental system for the control of surgically induced infections

The experimental system is described, and the procedures for surgery usage and maintenance are outlined. Basically the system consists of the following: (1) a portable clean room comprised of a horizontal laminar flow filter system and a transparent walled enclosure, (2) a helmet-shoulder pad assembly, (3) a communications system, (4) a helmet ventilation system, and (5) surgical gowns.

Source record↗

Application of planetary quarantine methodology and spacecraft sterilization technology to improved health care delivery.

In 1969 the Jet Propulsion Laboratory undertook an investigation to determine which of its space-derived capabilities could make significant contributions to the improvement of health care delivery in the U.S. The area of planetary quarantine was identified as one of high relevance. Two studies were conducted in this connection. The first study, which could contribute to infection reduction and control, was concerned with conversion of infection implicated complex, nonheat sterilizable equipment to dry heat, sterilizable equipment by changes in design and materials of construction. The second study area related to hospital acquired infection is clean room technology. A definite investigation has been performed to demonstrate and statistically evaluate performance under controlled conditions.

Green, R. H.↗

High temperature thermocouple development program, part A and part B

The problem of extending the useful life of thermocouples intended for in-core and out-of-core thermionic applications in a vacuum environment at temperatures up to 2273 K for periods of time up to 10,000 hours was investigated. Many factors that may influence this useful life were examined, and a basic probe design was developed. With a few modifications, twenty-three thermocouple assemblies were fabricated. Generally the finished thermocouple consisted of solid doped W-3% Re and W-25% Re wires and high purity and high density BeO insulators, and was sheathed in a high purity tantalum tube. In a few probes, stranded thermocouple wires were substituted; commercial grade BeO was used; and in two cases, CVD W-22% Re tubing was used. Each of the components was made of the highest purity materials available; was subjected to special cleaning steps, and was assembled in a class 10,000 clean room. Pertinent physical and chemical properties were determined on each of the components. Special processing techniques were used in the fabrication of the high purity (99.95%), high density (over 95% of theoretical) BeO.

Toenshoff, D. A.↗

Evaluation of membrane filter field monitors for microbiological air sampling

Due to area constraints encountered in assembly and testing areas of spacecraft, the membrane filter field monitor (MF) and the National Aeronautics and Space Administration-accepted Reyniers slit air sampler were compared for recovery of airborne microbial contamination. The intramural air in a microbiological laboratory area and a clean room environment used for the assembly and testing of the Apollo spacecraft was studied. A significantly higher number of microorganisms was recovered by the Reyniers sampler. A high degree of consistency between the two sampling methods was shown by a regression analysis, with a correlation coefficient of 0.93. The MF samplers detected 79% of the concentration measured by the Reyniers slit samplers. The types of microorganisms identified from both sampling methods were similar.

Fields, N. D.↗

Laser particulate spectrometer

Hybrid laser scattering and extinction technique measures particle diameters from 0.8 to 2.75 micrometers and speeds from 0.2 to 20 m/s. Operating pressures range from ambient to ultra-high vacuum, and temperatures range from 77 to 300 K. Potential applications include air pollution, clean room, and particle size monitoring.

Boyd, B. A.↗

Dust-contamination monitor

Compact instrument gives instantaneous reading of accumulation of small particles on glass plate. Instrument is sensitive to particles as small as one hundred microns and should be adaptable to monitoring particulate air pollution or dust levels in semiconductor clean rooms. Dual collimated light sources produce highly monochromatic radiation direct at grazing single angle onto glass plate.

Claysmith, C. R.↗

Direct delivery of automated spacecraft using the Shuttle - Thoughts for the designer

Following an outline of the main functions of the Tracking and Data Relay Satellite System (TDRSS) and the Astrophysics Transient Explorer (ATREX), the design options of the delivery into orbit of automated spacecraft, ATREX in particular, on board the Shuttle are discussed. The proportional counters used as detectors in ATREX need protection from humidity, so the spacecraft will be shipped in a sealed container filled with dry nitrogen and not opened until it is safely in the clean room at the launch site. The spacecraft and its booster will be loaded into a canister maintaining low humidity, to protect them all the way through the payload changeout room and into the Shuttle itself. After launching the Shuttle into orbit, the spacecraft will be tested on board the Shuttle just before releasing it. The future applications of this technique in Extravehicular Activity (EVA) and Gamma Ray Astronomy Observatories are discussed.

Townsend, M. R.↗

Shuttle optical environment; Proceedings of the Meeting, Washington, DC, April 23, 24, 1981

The numerical modeling, instrumentation, identification, and procedures to characterize and/or control contamination hazards to equipment used on the Shuttle are discussed. On-orbit pollutants include molecular offgassing and outgassing, particulate material, and substances from thrusters, vents, and leaks. Clean-rooms are being implemented in ground assembly and integration facilities. Attention is given to an upgraded SPACE program for numerically modeling contamination pathways and appropriate procedures to protect instrumentation from film and particulate deposition. Finally, attention is given to military cryogenic IR detectors being employed to quantify the Shuttle thermal and solid pollutant environment on-orbit as a prelude to future operational IR sensors.

Miller, E. R.↗

General contamination criteria for optical surfaces

Physical models are developed for establishing criteria to decide on the acceptable contamination level of optical devices in space-borne conditions. Optical systems can be degraded in terms of decreased throughput, i.e., transmissivity or reflectivity, or increases in the total integrated scatter (TIS). Performance losses can be caused by particulate accretion, molecular film accretion, and impact cratering. A quantitative relationship is defined for film thickness and loss of throughput. Formulas are also developed for cases where induced surface defects are larger than the desired viewing wavelengths, or smaller or of the same order of the observed wavelengths. The techniques are used to quantify the degradation of a VUV solar coronagraph, a VUV stellar telescope, and a solar cell due to TIS. Applications are projected for estimating the contamination sensitivity of specific instruments, assessing the contamination hazard from known particulates, or to define clean room standards.

Bremer, J. C.↗