25,453 research outputs found

    Data conditioning and display for Apollo prelaunch checkout - Test matrix technique

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    Test matrix technique for checkout and launching of Apollo-Saturn spacecraf

    PROJECTED COSTS AND RETURNS - RICE, LOUISIANA, 1997; PROJECTED COSTS AND RETURNS - SOYBEANS, CORN, MILO, WHEAT, AND WHEAT-SOYBEAN DOUBLE CROP, SOUTHWEST LOUISIANA, 1997

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    Farmers are annually faced with critical management decisions that impact the employment of production inputs for various crop enterprises and the combination of crops that will be assembled into a cropping system. The need for reliable information is crucial if sound production decisions are t o be made. Planning information plays a pivotal role in the development of 1997 production plans by farmers and is important in supporting their efforts to secure the necessary resources to carry out their plans. In addition, information regarding production alternatives and costs and returns for major crop enterprises is needed by extension personnel, researchers, lending institutions, and others involved in agriculture or agribusiness. This information has become all the more critical with the enactment of Federal Agricultural Improvement and Reform (FAIR) Act in 1996. The purpose of this report is to provide for tenant and owner operator situations the 1997 projected cost and return estimates for the following enterprises: rice in Southwest, Central, and Northeast Louisiana and soybean, corn, milo, wheat, and wheat-soybean double crop in Southwest Louisiana.Farm Management,

    Confocal laser scanning microscopy (CLSM) study of hepatocytes cultured on collagen films and gels

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    Summary of paper describing the process whereby primary hepatocyte cultures form an integral part of many hybrid artificial liver designs, and the extracellular matrix environment of the cultures is an important factor for optimal expression of hepatocyte-specific phenotype. This study investigates the effect of incorporating 20% chondroitin-6-sulphate (Ch6SO4), a glycosaminoglycan (GAG), into collagen films and gels, and crosslinking the films and the gels with 1,6-diaminohexane (DAH) on the viability of hepatocytes cultured for 48 hours

    Imaging X-ray spectrometer

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    An X-ray spectrometer for providing imaging and energy resolution of an X-ray source is described. This spectrometer is comprised of a thick silicon wafer having an embedded matrix or grid of aluminum completely through the wafer fabricated, for example, by thermal migration. The aluminum matrix defines the walls of a rectangular array of silicon X-ray detector cells or pixels. A thermally diffused aluminum electrode is also formed centrally through each of the silicon cells with biasing means being connected to the aluminum cell walls and causes lateral charge carrier depletion between the cell walls so that incident X-ray energy causes a photoelectric reaction within the silicon producing collectible charge carriers in the form of electrons which are collected and used for imaging

    Using ACIS on the Chandra X-ray Observatory as a particle radiation monitor II

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    The Advanced CCD Imaging Spectrometer is an instrument on the Chandra X-ray Observatory. CCDs are vulnerable to radiation damage, particularly by soft protons in the radiation belts and solar storms. The Chandra team has implemented procedures to protect ACIS during high-radiation events including autonomous protection triggered by an on-board radiation monitor. Elevated temperatures have reduced the effectiveness of the on-board monitor. The ACIS team has developed an algorithm which uses data from the CCDs themselves to detect periods of high radiation and a flight software patch to apply this algorithm is currently active on-board the instrument. In this paper, we explore the ACIS response to particle radiation through comparisons to a number of external measures of the radiation environment. We hope to better understand the efficiency of the algorithm as a function of the flux and spectrum of the particles and the time-profile of the radiation event.Comment: 10 pages, 5 figures, to be published in Proc. SPIE 8443, "Space Telescopes and Instrumentation 2012: Ultraviolet to Gamma Ray

    A five year record of high-frequency in situ measurements of non-methane hydrocarbons at Mace Head, Ireland

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    Continuous high-frequency in situ measurements of a range of non-methane hydrocarbons have been made at Mace Head since January 2005. Mace Head is a background Northern Hemispheric site situated on the eastern edge of the Atlantic. Five year measurements (2005–2009) of six C<sub>2</sub>–C<sub>5</sub> non-methane hydrocarbons have been separated into baseline Northern Hemispheric and European polluted air masses, among other sectors. Seasonal cycles in baseline Northern Hemispheric air masses and European polluted air masses arriving at Mace Head have been studied. Baseline air masses show a broad summer minima between June and September for shorter lived species, longer lived species show summer minima in July/August. All species displayed a winter maxima in February. European air masses showed baseline elevated mole fractions for all non-methane hydrocarbons. Largest elevations (of up to 360 ppt for ethane maxima) from baseline data were observed in winter maxima, with smaller elevations observed during the summer. Analysis of temporal trends using the Mann-Kendall test showed small (<6 % yr<sup>−1</sup>) but statistically significant decreases in the butanes and <i>i</i>-pentane between 2005 and 2009 in European air. No significant trends were found for any species in baseline air
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