4,886 research outputs found

    Do the design concepts used for the space flight hardware directly affect cell structure and/or cell function ground based simulations

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    The use of clinostats and centrifuges to explore the hypogravity range between zero and 1 g is described. Different types of clinostat configurations and clinostat-centrifuge combinations are compared. Some examples selected from the literature and current research in gravitational physiology are presented to show plant responses in the simulated hypogravity region of the g-parameter (0 is greater than g is greater than 1). The validation of clinostat simulation is discussed. Examples in which flight data can be compared to clinostat data are presented. The data from 3 different laboratories using 3 different plant species indicate that clinostat simulation in some cases were qualitatively similar to flight data, but that in all cases were quantitatively different. The need to conduct additional tests in weightlessness is emphasized

    Benchtop Centrifuge for Materials Science

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    The Benchtop Centrifuge was designed to serve for research purposes within theMechanical Engineering Department at Santa Clara University. The prototype has been completely assembled and is functioning to the desired specifications of applying up to 1000 g’s of force for over 4 hours. The current uses are anticipated for separation of particles within materials for material processing and testing. The overall systemdesign has been adapted froma legacy project within the University. Various tests were conducted in order to ensure safety and usability of the system. Through Abaqus analysis and drop-test experiments, it was found enclosure itself can withstand an impact from a bucket at max-speed. The a SolidWorks analysis, the natural frequency of the enclosure was found to be 104.46 Hz, which translates to a rotational speed of 6267.6 RPM; this is well above what the system will be operating at. The team hopes that future students and faculty will be able to expand their current research through the use of this system

    DEVELOPMENT OF COMPUTING MODEL OF GEOMECHANICS SYSTEM «LAYERED MASSIF - WORKING SUPPORT» AT PHYSICAL PARAMETERS OF ROCKS

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    Substantiation of method forecasting of manifestation rock pressure in the system «layered massif – working support» based on the detection of patterns displacement any point of circuit the preparatory working during the simulation experiments

    A proposal to determine properties of the gravitropic response of plants in the absence of a complicating g-force (GTHRES)

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    Gravitropic responses of oat seedlings (Avena sativa L.) were measured on Earth and in microgravity (IML-1). The seedlings were grown at 1 g either on Earth or on 1 g centrifuges. They were challenged by centripetal accelerations for which the intensity and duration of the stimulations were varied. All stimulation intensities were in the hypogravity region from 0.1 to 1.0 g. All responses occurred either in Spacelab microgravity or during clinorotation on Earth. The experiments were carried out with the same apparatus in Spacelab and on Earth. The experiments addressed a series of scientific questions and useful data were obtained to provide answers to some but not all of those questions

    Countercurrent chromatography in analytical chemistry (IUPAC technical report)

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    © 2009 IUPACCountercurrent chromatography (CCC) is a generic term covering all forms of liquid-liquid chromatography that use a support-free liquid stationary phase held in place by a simple centrifugal or complex centrifugal force field. Biphasic liquid systems are used with one liquid phase being the stationary phase and the other being the mobile phase. Although initiated almost 30 years ago, CCC lacked reliable columns. This is changing now, and the newly designed centrifuges appearing on the market make excellent CCC columns. This review focuses on the advantages of a liquid stationary phase and addresses the chromatographic theory of CCC. The main difference with classical liquid chromatography (LC) is the variable volume of the stationary phase. There are mainly two different ways to obtain a liquid stationary phase using centrifugal forces, the hydrostatic way and the hydrodynamic way. These two kinds of CCC columns are described and compared. The reported applications of CCC in analytical chemistry and comparison with other separation and enrichment methods show that the technique can be successfully used in the analysis of plants and other natural products, for the separation of biochemicals and pharmaceuticals, for the separation of alkaloids from medical herbs, in food analysis, etc. On the basis of the studies of the last two decades, recommendations are also given for the application of CCC in trace inorganic analysis and in radioanalytical chemistry

    Aerospace medicine and biology: A continuing bibliography with indexes, supplement 164

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    This bibliography lists 275 reports, articles, and other documents introduced into the NASA scientific and technical information system in January 1977

    The Legacy of the X-15

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    The X-15 established such widespread confidence in aerodynamic, thermal, and structural areas that new designs for operation aircraft for any speed regime could be expected to be successfully achieved if good use was made of all pertinent test facilities and analytical methods. This philosophy guided design of the space shuttle and is the real legacy of the X-15. The accomplishments and contributions attributable to the research and development work on the X-15 that influenced the formative years of the Space Shuttle Program are presented

    NASA guidelines on report literature

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    NASA seeks for inclusion in its Scientific and Technical Information System research reports, conference proceedings, meeting papers, monographs, and doctoral and post graduate theses which relate to the NASA mission and objectives. Topics of interest to NASA are presented
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