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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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At least 1,063 records · Page 59
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

On evaluating compliance with air pollution levels 'not to be exceeded more than once per year'

The point of view taken is that the Environmental Protection Agency (EPA) Air Quality Standards (AQS) represent conditions which must be made to exist in the ambient environment. The statistical techniques developed should serve as tools for measuring the closeness to achieving the desired quality of air. It is shown that the sampling frequency recommended by EPA is inadequate to meet these objectives when the standard is expressed as a level not to be exceeded more than once per year and sampling frequency is once every three days or less frequent.

Neustadter, H. E.↗
NASA NTRS1974

The problem of pollution for the SST

A qualitative review of the possible effects of the exhaust gases discharged by a large fleet of SSTs in the upper atmosphere is given. The review indicates the importance of the NO production in the exhaust gases. The mechanism of NO formation by the combustion process is described. A method for reduction of the NO formation is presented.

Ferri, A.↗
NASA NTRS1974

A study of a dual polarization laser backscatter system for remote identification and measurement of water pollution

Remote identification and measurement of subsurface water turbidity and oil on water was accomplished with analytical models which describe the backscatter from smooth surface turbid water, including single scatter and multiple scatter effects. Lidar measurements from natural waterways are also presented and compared with ground observations of several physical water quality parameters.

Sheives, T. C.↗
NASA NTRS1974

Global measurements of air pollution from satellites

The conceptual design of an FOV nadir radiometer was examined for its applicability to monitoring the radiation process in the atmosphere as it relates to aerosol behavior. The instrument employs a gas filter correlation technique and is suitable for transportation onboard satellite.

Acton, L. L.↗
NASA NTRS1974

A Simulation Model for Studying Effects of Pollution and Freshwater Inflow on Secondary Productivity in an Ecosystem

A mathematical model of an ecosystem is developed. Secondary productivity is evaluated in terms of man related and controllable factors. Information from an existing physical parameters model is used as well as pertinent biological measurements. Predictive information of value to estuarine management is presented. Biological, chemical, and physical parameters measured in order to develop models of ecosystems are identified.

Johnson, R. W.↗
NASA NTRS1973

Feasibility of remote sensing for detecting thermal pollution. Part 1: Feasibility study. Part 2: Implementation plan

A feasibility study for the development of a three-dimensional generalized, predictive, analytical model involving remote sensing, in-situ measurements, and an active system to remotely measure turbidity is presented. An implementation plan for the development of the three-dimensional model and for the application of remote sensing of temperature and turbidity measurements is outlined.

Veziroglu, T. N.↗
NASA NTRS1973

Pollution monitoring system

An investigation was undertaken to identify those photographic laboratory by-products which can produce harmful reactions if released untreated. After identification of these by-products, specific monitoring systems for each of the offending ions were investigated and recommendations for implementation are presented. Appropriate monitoring systems are discussed.

Goodding, R. A.↗
NASA NTRS1975

Water hyacinths and alligator weeds for removal of lead and mercury from polluted waters

Removal of lead and mercury by water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb. was investigated. Water hyacinths demonstrated the ability to remove 0.176 mg of lead and 0.150 mg of mercury per gram of dry plant material from distilled water and river water in a 24-hour period. One acre of water hyacinths is potentially capable of removing 105.6 grams of lead and 90.0 grams of mercury per day. Alligator weeds removed 0.101 mg of lead per gram of dry plant material in a 24-hour period. This same plant also demonstrated the ability to remove a minimum of 0.153 mg of mercury per gram of dry plant material in a six hour period.

Wolverton, B. C.↗
NASA NTRS1975

A theoretical/experimental program to develop active optical pollution sensors, part 2

Progress is reported on experimental investigations of Lidar and the application of Lidar to environmental and atmospheric science. Specifically the following programs are considered: calibration and application of the LaRC 48-inch Lidar; efficient and certain detection of SO2 and other gases in the calibration tank using the Raman Stack Monitor Lidar; the potential of Lidar remote sensing from the space shuttle; and the planning and mounting of efforts to realize the promise of backscatter differential absorption Lidar.

Poultney, S. K.↗
NASA NTRS1975

Water hyacinths and alligator weeds for removal of silver, cobalt, and strontium from polluted waters

Water hyacinths and alligator weeds demonstrated the ability to rapidly remove heavy metals from an aqueous system by root absorption and concentration. Water hyacinths demonstrated the ability to remove 0.439 mg of silver, 0.568 mg of cobalt, and 0.544 mg of strontium in an ionized form per gram of dry plant material in a 24-hour period. Alligator weeds removed a maximum of 0.439 mg of silver, 0.130 mg of cobalt, and 0.161 mg of strontium per gram of dry plant material per day.

Wolverton, B. C.↗
NASA NTRS1975

Exhaust pollutant emissions from swirl-can combustor module arrays at parametric test conditions

Improved designs of swirl-can combustor modules were tested using seven-module arrays in a combustor. The combustor was operated over a pressure range of 69 to 207 N/sq cm, a fuel-air ratio range of 0.015 to 0.046, at a constant inlet air temperature of 733 K, and at reference velocities of 23.9 and 30.6 m/sec. The three designs tested performed with high combustion efficiency at all conditions tested and exhibited oxides of nitrogen emissions substantially lower than that of conventional gas turbine combustors. A correlating parameter used to extrapolate oxides of nitrogen emissions to full power or takeoff conditions for large commercial turbofan engines predicts oxides of nitrogen emissions somewhat higher than those specified in the 1979 government emissions standards.

Mularz, E. J.↗
NASA NTRS1974

Satellite detection of vegetative damage and alteration caused by pollutants emitted by a zinc smelter

The author has identified the following significant results. Field observations and data collected by low flying aircraft were used to verify the accuracy of maps produced from the satellite data. Although areas of vegetation as small as six acres can accurately be detected, a white pine stand that was severely damaged by sulfur dioxide could not be differentiated from a healthy white pine stand because spectral differences were not large enough. When winter data were used to eliminate interference from herbaceous and deciduous vegetation, the damage was still undetectable. The analysis was able to produce a character map that accurately delineated areas of vegetative alteration due to high zinc levels accumulating in the soil. The map depicted a distinct gradient of less damage and alteration as the distance from the smelter increased. Although the satellite data will probably not be useful for detecting small acreages of damaged vegetation, it is concluded that the data may be very useful as an inventory tool to detect and delineate large vegetative areas possessing differing spectral signatures.

Mcmurtry, G. J.↗
NASA NTRS1975

Oil-pollution detection and monitoring from space using ERTS-1

The author has identified the following significant results. Three reported spills were investigated using four digital computer, compatible techniques on ERTS - 1 data. A spill on the Atlantic Ocean (off Virginia) was studied to develop spectral signatures. Another spill, in Oakland Bay, was studied by ratioing spectral channels (to try to eliminate turbidity effects) and by summing different spectral channels to look for anomolus values caused by oil. The final spill, off Southern California, was investigated by looking for anomolus values in each channel separately. Results indicate that any of these methods might be usable if the spill is large enough to be seen by satellite, if the spill occurs more than a few kilometers off shore, and if the sky and water are relatively clear. In the case of the Atlantic spill, identification of material was not possible; and in the other two cases, the spills could not be detected at all. ERTS-1 was not considered feasible for this type of work because of its 18 day overpass frequency, the few spectral channels, the extended bandwidths, and the long, information retrieval time.

Horvath, R.↗