534 research outputs found

    Reusable silica surface-insulation material

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    Material was specifically developed for manufacture of insulating tiles, but it can be molded into other shapes as required. Basic raw materials are high-purity silica fiber, fumed-silica powder, and reagent-grade starch. Only purest materials are used, and care must be taken to avoid contamination during processing

    Fibrous refractory composite insulation

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    A refractory composite insulating material was prepared from silica fibers and aluminosilicate fibers in a weight ratio ranging from 1:19 to 19:1, and about 0.5 to 30% boron oxide, based on the total fiber weight. The aluminosilicate fiber and boron oxide requirements may be satisfied by using aluminoborosilicate fibers and, in such instances, additional free boron oxide may be incorporated in the mix up to the 30% limit. Small quantities of refractory opacifiers, such as silicon carbide, may be also added. The composites just described are characterized by the absence of a nonfibrous matrix

    Silica reusable surface insulation

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    A reusable silica surface insulation material is provided by bonding amorphous silica fibers with colloidal silica at an elevated temperature. The surface insulation is ordinarily manufactured in the form of blocks (i.e., tiles)

    Introduction: Academic Freedom and Tenure Symposium

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    Threats to Academic Freedom and Tenure

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    Adjustable high emittance gap filler

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    A flexible, adjustable refractory filler is disclosed for filling gaps between ceramic tiles forming the heat shield of a space shuttle vehicle, to protect its aluminum skin during atmospheric reentry. The easily installed and replaced filler consists essentially of a strip of ceramic cloth coated, at least along both its longitudinal edges with a room temperature vulcanizable silicone rubber compound with a high emittance colored pigment. The filler may have one or more layers as the gap width requires. Preferred materials are basket weave aluminoborosilicate cloth, and a rubber compounded with silicon tetraboride as the emittance agent and finely divided borosilicate glass containing about 7.5% B2O3 as high temperature binder. The filler cloth strip or tape is cut to proper width and length, inserted into the gap, and fastened with previously applied drops of silicone rubber adhesive

    Information Flow Impediments in Disaster Relief Supply Chains

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    Supply Chain Management (SCM) is seldom more difficult than during disaster relief efforts. As supply chains quickly form in response to a disaster, a slow information flow presents a major hindrance to coordinating the allocation of resources necessary for disaster relief efforts. This paper identifies impediments to the flow of information through supply chains following large scale and catastrophic disasters. Given the scarce body of literature on this subject, a grounded theory case study was conducted to examine an extreme case. The study concentrates on the efforts of multiple organizations and individuals that provided relief in the aftermath of Hurricane Katrina, which battered the Gulf Coast of the southeastern United States in late 2005. Data was gathered from diverse sources, including government agencies, profit and non-profit organizations, and individuals, during and after the disaster. Based on our data analysis, we not only identify information flow impediments (i.e., inaccessibility, inconsistent data and information formats, inadequate stream of information, low information priority, source identification difficulty, storage media misalignment, unreliability, and unwillingness), but also identify likely sources of these impediments, and examine their consequences to organizations’ disaster recovery efforts. Our findings suggest some potential design principles for devising solutions capable of reducing or alleviating the impact of information flow impediments in future disasters

    Zystische Adventitiadegeneration (CAD) als Ursache einer invalidisierenden Claudicatio intermittens

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    Zusammenfassung: Bei einem 45-jährigen Patienten mit wechselhaften Ischämiebeschwerden und initial limitierter Gehstrecke rechts von höchstens 50m führten die duplexsonographischen und angiographischen Abklärungen zur Verdachtsdiagnose einer zystischen Adventitiadegeneration. Intraoperativ zeigte sich ein zystisch aufgetriebenes Poplitealsegment mit Entleerung von gallertiger Flüssigkeit. Aufgrund der langstreckigen Veränderung erfolgte die Segmentresektion der A.poplitea und Rekonstruktion mittels eines autologen Veneninterponats. Die CAD ist ein seltenes Krankheitsbild, an das gerade bei jungen Patienten ohne systemische Arteriosklerose gedacht werden sollte. Die Therapie ist je nach Fall chirurgisch erhaltend durch Zystenresektion mittels "Exarterektomie" oder gefäßresezierend, insbesondere bei langstreckigen Veränderungen bzw. vollständiger Okklusion mittels Ersatz durch ein Veneninterpona
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