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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Static properties of lungs after oxygen exposure.
Atelectatic and direct toxic effects of oxygen on human subjects
Inhibited 1,1,1-trichloroethane replaces trichloroethylene for degreasing
In fight against air pollution inhibited TCE /1,1,1-trichloroethane/ is effective substitute for trichloroethylene in degreasing plants. This chemical has only slight photochemical activity and causes little eye irritation. TCE is less toxic than trichloroethylene and can withstand production loads and conditions, or long term storage, without degradation.
Self-sealing, easily purged quick-disconnect hose coupling
Coupling for pressurized hoses handles gas or liquid, is easily purged, and automatically seals the hose when disconnected. Volatile or toxic materials can be isolated before the connection is broken. This device may interest food processors and manufacturers of fluid delivery systems.
Study of space station propulsion system resupply and repair Monthly progress report, 1 Jan. - 1 Feb. 1970
Evaluating toxicity of propellant within space station, leakage criteria of propellant and nitrogen, and weight comparisons of five candidate resupply systems - graphs
Analysis of lower atmospheric data for diffusion studies
Mathematical diffusion models and meteorological inputs for estimating toxic fuel hazards at Kennedy Space Center
Instant acting adhesive system
Adhesive developes 80 percent of minimum bond strength of 250 psi less than 30 sec after activation is required. Adhesive is stable, handles easily, is a low toxic hazard, and is useful in industrial and domestic prototype bonding and clamping operations.
Estimating carbon monoxide exposure
Method predicts effects of carbon monoxide on astronauts confined in spacecraft cabin atmospheres. Information on need for low toxicity level also applies to confined spaces. Benefits are applicable to industry and public health.
The Hekla fires - A preliminary report of the 1970 Mount Hekla volcanic eruption. A report from the Smithsonian Insitution Center for Short-Lived Phenomena, 15 June 1970
Describing eruption in region of Mt. Hekla, Iceland and toxic hazards from volcanic ash
Exposure system for animals Patent
System for continuous monitoring of exhalations, weighing, and cage cleaning for animal exposed to controlled atmosphere for toxic study
Effects of controlled atmosphere constituents and trace metals on metabolism and metabolically vital organs Semiannual status report
Bioenergetics protocol for evaluating effects of environment on biological systems, including metabolic effects of diluent gases and oxygen toxicity
Effect of dietary antioxidant level and oxygen exposure on the fine structure of the proximal convoluted tubules
Dietary antioxidant vitamin level effects on fine structure of proximal convoluted tubules in rats, studying changes due to oxygen toxicity
Mercury in the environment
Problems in assessing mercury concentrations in environmental materials are discussed. Data for situations involving air, water, rocks, soils, sediments, sludges, fossil fuels, plants, animals, foods, and man are drawn together and briefly evaluated. Details are provided regarding the toxicity of mercury along with tentative standards and guidelines for mercury in air, drinking water, and food.
Metered oxygen supply aids treatment of domestic sewage
Microbiological fixed-bed process was developed in which supplementary oxygen required by microbial species is supplied by electrochemical device. Rate of addition of oxygen to waste treatment process is controlled to maintain aerobic metabolism and prevent anaerobic metabolisms which produce odorous or toxic products.
Determining and analyzing the strength and impact resistance of high modulus glass
A number of new glass compositions have been prepared with increased emphasis on compositions without beryllia. Glass preparations have been much more broadly based and have included the eutectic glass fields, and the mullite-rare earth glass systems. Of the new glasses, the best non-toxic composition is UARL 472 with a bulk modulus of only 18.20 million psi. A second experimental glass, UARL 417, was chosen for research in making large quantities of fiber in monofilament form. Tests of these UARL 417 epoxy resin samples in comparison to similar composites made with the DuPont organic fiber, PRD-49-1, show that the UARL composites have a compressive strength 41/2 times higher and a specific compressive strength at least 21/2 times greater. Much of the research effort attempted to answer the question of why a given glass should have an impact strength superior to other glasses. No definitive answer to the question was found.
A review of carbon monoxide sources, sinks, and concentrations in the earth's atmosphere
Carbon monoxide is a toxic pollutant which is continually introduced into the earth's atmosphere in significant quantities. There are apparently some mechanisms operating which destroy most of the CO in the atmosphere, i.e., a carbon monoxide sink. These mechanisms have not as yet been established in a quantitative sense. This report discusses the various possible removal mechanisms which warrant serious consideration. Particular emphasis is given to chemical reactions (especially that with OH), soil bacteria and other biological action, and transport effects. The sources of carbon monoxide, both natural and anthropogenic, are reviewed and it is noted that there is quite possibly a significant undefined natural source. Atmospheric CO concentrations are discussed and their implications on carbon monoxide lifetime, sinks and sources are considered.
Continuous animal exposure to dichloromethane
Continuous exposures of dogs, monkeys, rats and mice to 5000 ppm and 1000 ppm of dichloromethane vapor (CH2Cl2) produced severe toxic effects on dogs, rats and mice. Dogs died after 3 weeks exposure to 1000 ppm and after 6 weeks exposure to 5000 ppm. Thirty percent of the mice also succumbed during four weeks exposure to 5000 ppm CH2Cl2. Although rats survived 14 weeks exposure to 5000 ppm, they experienced subnormal weight gains. Significant gross and histopathological hepatic lesions were noted in all 3 species at death or experimental termination in 14 weeks. In addition, rats showed abnormal kidney histopathology. Fat stains disclosed mild fatty increase in monkey livers after 14 weeks exposure to 1000 ppm CH2Cl2.
Overview of the earth resources program of the Jet Propulsion Laboratory
Proposed is an investigation to develop and correlate remote sensing from satellites and aircraft into an effective prototype system for California statewide water quality surveillance. Aircraft overflights, computer enhanced recognition of pollution signatures, ground truth measurements, and data processing will be employed to develop a simplified and automated monitoring system. ERTS A image data will be used for nine major drainage basins of California having unique water quality influences from waste discharges, thermal contributions, oil spills, turbidity, sea water intrusion, agricultural drainage, toxicity, biostimulation, and eutrophication.