5,438 research outputs found

    Lunar exploration for resource utilization

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    The strategy for developing resources on the Moon depends on the stage of space industrialization. A case is made for first developing the resources needed to provide simple materials required in large quantities for space operations. Propellants, shielding, and structural materials fall into this category. As the enterprise grows, it will be feasible to develop additional sources - those more difficult to obtain or required in smaller quantities. Thus, the first materials processing on the Moon will probably take the abundant lunar regolith, extract from it major mineral or glass species, and do relatively simple chemical processing. We need to conduct a lunar remote sensing mission to determine the global distribution of features, geophysical properties, and composition of the Moon, information which will serve as the basis for detailed models of and engineering decisions about a lunar mine

    Mars resources

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    The most important resources of Mars for the early exploration phase will be oxygen and water, derived from the Martian atmosphere and regolith, which will be used for propellant and life support. Rocks and soils may be used in unprocessed form as shielding materials for habitats, or in minimally processed form to expand habitable living and work space. Resources necessary to conduct manufacturing and agricultural projects are potentially available, but will await advanced stages of Mars habitation before they are utilized

    Application of manufactured products

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    A wide range of products can be manufactured from the following materials: (1) lunar regolith or basalt; (2) regolith or rock beneficiated to concentrate plagioclase or other minerals; (3) iron, extracted from lunar soil or rocks by various means; (4) naturally occurring or easily obtained materials that have cementitious properties; and (5) byproducts of the above materials. Among the products that can be produced from these materials are the following: beams; plates and sheets; transparent plates (windows); bricks and blocks; pipes and tubes; low-density materials (foams); fiber, wire, and cables; foils and reflective coatings; hermetic seals (coatings); and formed objects. In addition to oxygen, which can be obtained by several processes, either from unbeneficiated regolith or by reduction of concentrated ilmenite, these materials make the simplest requirements of the lunar resource extraction system. A thorough analysis of the impact of these simplest products on the economics of space operations is not possible at this point. Research is necessary both to define optimum techniques and adapt them to space and to determine the probable market for the products so that the priority of various processes can be assessed. Discussions of the following products are presented: aerobraking heat shields; pressurized habitats; lunar photovoltaic farms; and agricultural systems

    The 1984 NASA/ASEE summer faculty fellowship program

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    An overview is given of the program management and activities. Participants and research advisors are listed. Abstracts give describe and present results of research assignments performed by 31 fellows either at the Johnson Space Center, at the White Sands test Facility, or at the California Space Institute in La Jolla. Disciplines studied include engineering; biology/life sciences; Earth sciences; chemistry; mathematics/statistics/computer sciences; and physics/astronomy

    Configurations of Extremal Even Unimodular Lattices

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    We extend the results of Ozeki on the configurations of extremal even unimodular lattices. Specifically, we show that if L is such a lattice of rank 56, 72, or 96, then L is generated by its minimal-norm vectors.Comment: 8 pages. To appear, International Journal of Number Theor

    Summer Workshop on Near-Earth Resources

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    The possible large scale use of extraterrestrial resources was addressed, either to construct structures in space or to return to Earth as supplements for terrestrial resources. To that end, various specific recommendations were made by the participants in the summer study on near-Earth resources, held at La Jolla, California, 6 to 13 August, 1977. The Moon and Earth-approaching asteroids were considered. Summaries are included of what is known about their compositions and what needs to be learned, along with recommendations for missions designed to provide the needed data. Tentative schedules for these projects are also offered

    The role of evidence and the expert in contemporary processes of governance: the case of opioid substitution treatment policy in England

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    Background This paper is based on research examining stakeholder involvement in substitution treatment policy which was undertaken as part of the EU funded FP7 ALICE-RAP (Addictions and Lifestyles in Contemporary Europe – Reframing Addictions Project). In England, the research coincided with a policy shift towards a recovery orientated drug treatment framework and a heated debate surrounding the role of substitute prescribing. The study aimed to explore the various influences on the development of the new ‘recovery’ policy from the perspectives of the key stakeholders involved. Methods The paper is based on documentary analyses and key informant interviews with a range of stakeholders, including representatives of user organisations, treatment providers, civil servants, and members of expert committees. Results Drawing on the theoretical insights offered by Backstrand’s ‘civic science’ framework, the changing role of evidence and the position of experts in the processes of drugs policy governance are explored. ‘Evidence’ was used to problematise the issue of substitution treatment and employed to legitimise, justify and construct arguments around the possible directions of policy and practice. Conflicting beliefs about drug treatment and about motivation for policy change emerge in the argumentation, illustrating tensions in the governance of drug treatment and the power differentials separating different groups of stakeholders. Their role in the production of evidence also illustrates issues of power regarding the definition and development of ‘usable knowledge’. There were various attempts at greater representation of different forms of evidence and participation by a wider group of stakeholders in the debates surrounding substitution treatment. However, key national and international experts and the appointment of specialist committees continued to play dominant roles in building consensus and translating scientific evidence into policy discourse. Conclusion Substitution treatment policy has witnessed a challenge to the dominance of ‘scientific evidence’ within policy decision making, but in the absence of alternative evidence with an acceptable credibility and legitimacy base, traditional notions of what constitutes evidence based policy persist and there is a continuing lack of recognition of ‘civic science’

    Tunneling Anisotropic Magnetoresistance of Helimagnet Tunnel Junctions

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    We theoretically investigate the angular and spin dependent transport in normal-metal/helical-multiferroic/ferromagnetic heterojunctions. We find a tunneling anisotropic magnetoresistance (TAMR) effect due to the spiral magnetic order in the tunnel junction and to an effective spin-orbit coupling induced by the topology of the localized magnetic moments in the multiferroic spacer. The predicted TAMR effect is efficiently controllable by an external electric field due to the magnetoelectric coupling

    Responses of Hyalella azteca and Ceridaphnia dubia to reservoir sediments following Chelated Copper Herbicide Applications

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    In response to nuisance growths of algae and vascular plants, such as dioecious hydrilla ( Hydrilla verticillata L.f. Royle), copper formulations have been applied in lakes and reservoirs for a number of years. Concerns have arisen regarding the long-term consequences of copper applications and those concerns have appropriately focused on sediment residues. In this study, we evaluated the toxicity of sediments from treated (for a decade) and untreated areas in Lake Murray, South Carolina and estimated the capacity of those sediments to bind additional copper. Two sentinel aquatic invertebrates, Hyalella azteca Saussure and Ceriodaphnia dubia Richard, were used to measure residual toxicity of treated and untreated sediments from the field and after laboratory amendments. (PDF has 5 pages.

    Manufacturing and fabrication, part 3

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    The accessibility of material and energy off the Earth and the leverage that these nonterrestrial resources can exert on the space transportation system are important influences on the long-term goal of exploring the solar system. Research on separation of lunar materials and manufacturing of useful products from them is in its infancy. A few possible processes and products are described in this report. Specific attention is given to oxygen, metal, and silicate products
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