26,722 research outputs found

    Bioprocessing of ores: Application to space resources

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    The role of microorganisms in the oxidation and leaching of various ores (especially those of copper, iron, and uranium) is well known. This role is increasingly being applied by the mining, metallurgy, and sewage industries in the bioconcentration of metal ions from natural receiving waters and from waste waters. It is concluded that bioprocessing using bacteria in closed reactors may be a variable option for the recovery of metals from the lunar regolith. Obviously, considerable research must be done to define the process, specify the appropriate bacteria, determine the necessary conditions and limitations, and evaluate the overall feasibility

    Retail Rate Impacts of Distributed Solar: Focus on New England

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    The Lawrence Berkeley National Laboratory (LBNL) recently issued a study entitled “Putting the Potential Rate Impacts of Distributed Solar into Context,” authored by Galen Barbose. The LBNL study estimates the potential rate impact of distributed solar on national average retail electricity prices, and importantly, compares that impact to the potential impact of other rate drivers such as natural gas prices, renewable portfolio standards, and utility capital expenditures.1 This brief applies a similar style analysis as used by LBNL to regional and state level data to estimate more granular impacts for New England. We estimate rate impacts for various penetration rates of net metered distributed solar and compare them to the potential rate impacts of future natural gas prices, energy efficiency gains, RPS costs, RGGI costs, and utility capital expenditures. Like LBNL, we attempt to isolate the impact of these rate drivers as well as represent uncertainty around future policy choices, commodity costs, and technology costs

    Life support and self-sufficiency in space communities

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    The development of a controlled ecological life support system (CELSS) is necessary to enable the extended presence of humans in space, as on the Moon or on another planetary body. Over a long period, the provision of oxygen, water, and food, and protection from such inimical agents as radiation and temperature extremes, while maintaining the psychological health of the subjects, becomes prohibitively expensive if all supplies must be brought from Earth. Thus, some kind of a regenerative life support system within an enclosure or habitat must be established, thereby cutting the umbilicus to Mother Earth, but not irreversibly. This protective enclosure will enable the survival and growth of an assemblage of terrestrial species of microorganisms, plants, and animals. It is envisioned that the nonterrestrial ecosystem will evolve through the sequential introduction of terrestrial and local materials, together with the appropriate living forms

    On the contribution of binocular disparity to the long-term memory for natural scenes

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    Binocular disparity is a fundamental dimension defining the input we receive from the visual world, along with luminance and chromaticity. In a memory task involving images of natural scenes we investigate whether binocular disparity enhances long-term visual memory. We found that forest images studied in the presence of disparity for relatively long times (7s) were remembered better as compared to 2D presentation. This enhancement was not evident for other categories of pictures, such as images containing cars and houses, which are mostly identified by the presence of distinctive artifacts rather than by their spatial layout. Evidence from a further experiment indicates that observers do not retain a trace of stereo presentation in long-term memory

    Far-infrared laser spectroscopy of phonon difference band absorption in TlCl

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    Far-infrared laser radiation is used to study the lattice absorption of a TlCl crystal over a large temperature range. We found a strong absorption band caused by phonon difference processes where longitudinal and transverse acoustic phonons with wave vectors at the Brillouin zone boundary are involved
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