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Fields, B.

Publications and source records attributed to Fields, B..

Advanced Life Support Systems: Opportunities for Technology Transfer

NASA's future missions to explore the solar system will be of long-duration possibly lasting years at a time. Human life support systems will have to operate with very high reliability for these long periods with essentially no resupply from Earth. Such life support systems will make extensive use of higher plants, microorganisms, and physicochemical processes for recycling air and water, processing wastes, and producing food. Development of regenerative life support systems will be a pivotal capability for NASA's future human missions. A fully functional closed loop human life support system currently does not exist and thus represents a major technical challenge for space exploration. Technologies where all life support consumables are recycled have many potential terrestrial applications as well. Potential applications include providing human habitation in hostile environments such as the polar regions or the desert in such a way as to minimize energy expenditures and to minimize negative impacts on those often ecologically-sensitive areas. Other potential applications include production of food and ornamental crops without damaging the environment from fertilizers that contaminate water supplies; removal of trace gas contaminants from tightly sealed, energy-efficient buildings (the so-called sick building syndrome); and even the potential of gaining insight into the dynamics of the Earth's biosphere such that we can better manage our global environment. Two specific advanced life support technologies being developed by NASA, with potential terrestrial application, are the zeoponic plant growth system and the Hybrid Regenerative Water Recovery System (HRWRS). The potential applications for these candidate dual use technologies are quite different as are the mechanisms for transfer. In the case of zeoponics, a variety of commercial applications has been suggested which represent potentially lucrative markets. Also, the patented nature of this product offers opportunities for licensing to commercial entities. In the case of the HRWRS, commercial markets with broad applications have not been identified but some terrestrial applications are being explored where this approach has advantages over other methods of waste water processing. Although these potential applications do not appear to have the same broad attraction from the standpoint of rapid commercialization, they represent niches where commercialization possibilities as well as social benefits could be realized.

Fields, B.

The boron-to-beryllium ratio in halo stars - A signature of cosmic-ray nucleosynthesis in the early Galaxy

We discuss Galactic cosmic-ray (GCR) spallation production of Li, Be, and B in the early Galaxy with particular attention to the uncertainties in the predictions of this model. The observed correlation between the Be abundance and the metallicity in metal-poor Population II stars requires that Be was synthesized in the early Galaxy. We show that the observations and such Population II GCR synthesis of Be are quantitatively consistent with the big bang nucleosynthesis production of Li-7. We find that there is a nearly model independent lower bound to B/Be of about 7 for GCR synthesis. Recent measurements of B/Be about 10 in HD 140283 are in excellent agreement with the predictions of Population II GCR nucleosynthesis. Measurements of the boron abundance in additional metal-poor halo stars is a key diagnostic of the GCR spallation mechanism. We also show that Population II GCR synthesis can produce amounts of Li-6 which may be observed in the hottest halo stars.

Walker, T. P.

Digital image-rectification system

System removes spatial distortions from data and brings data into conformance with Universal Transverse Mercator map projection, produces digital output products suitable for further machine processing and analysis, and fills need for geometrically corrected Landsat multispectral scanner digital data in several remote sensing application areas.

Van Wie, P. H.