5,338 research outputs found

    Space environmental effects: Construction and utilization of a system to measure low thermal strain in one meter graphite epoxy tubes

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    A system for measuring the expansion of low coefficient of thermal expansion (CTE) materials was constructed around a H.P. 5526-A laser measuring system. The vacuum CTE measurements in the -150 F to +120 F range were made over a 6 month period on a graphite epoxy tube yielding CTE values of 2.5 to one fifty-millionth/F above ambient and 2 + or - one ten-millionth F below ambient temperature. To assure that the below ambient, approximately 10 microns high open loop nature of the delta L/L vs. T curves was not apparatus related, similar size quartz tubes (A and B) were checked and found to have only a 2 micron (negligable for quartz) open loop component. These two quartz tubes, A and B, had ambient CTE values 20% and 45% respectively higher than the average handbook value. The overnight microcreep diminished an order of magnitude during the first several cycles after the system had been reopened

    Chemical treatment makes aromatic polyamide fabric fireproof in oxygen atmosphere

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    Organic fabric is reacted first with vapors of a phosphorus oxychloride, phosphorus oxybromide solution and then with bromine vapor, after neutralization it is flameproof in pure oxygen atmosphere. Soaking the fabric with mixture of ammonium polyphosphates increases flame resistance, but the polyphosphates are leached out during laundering

    Abandoned Horses, Whose Property?

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    Creating Womanhood

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    A close reading of Jennifer Finney Boylan’s She’s Not There, a transition from male to female memoir, makes the author question every perception of gender differences held until that moment: Why are some people born into the “wrong” body? What causes gender “dysphoria” [for lack of a better name]? Can we recreate ourselves? What exactly happens during a sex change procedure? What does it mean to BE a woman

    LDEF solar cell radiation effects analysis

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    Because of the extended time that the Long Duration Exposure Facility (LDEF) mission stayed in space, the solar cells on the satellite experienced greater environments than originally planned. The cells showed an overall degradation in performance that is due to the combined effects of the various space environments. The purpose of this analysis is to calculate the effect of the accumulated radiation on the solar cells, thereby helping Marshall Space Flight Center (MSFC) to unravel the relative power degradation from the different environments
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