78 research outputs found

    Overview of NASA FINESSE (Field Investigations to Enable Solar System Science and Exploration) Science and Exploration Results

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    NASA's FINESSE (Field Investigations to Enable Solar System Science and Exploration) project is focused on a science and exploration field-based research program to generate strategic knowledge in preparation for human and robotic exploration of other planetary bodies including our moon, Mars' moons Phobos and Deimos, and near-Earth asteroids. Scientific study focuses on planetary volcanism (e.g., the formation of volcanoes, evolution of magma chambers and the formation of multiple lava flow types, as well as the evolution and entrapment of volatile chemicals) and impact cratering (impact rock modification, cratering mechanics, and the chronologic record). FINESSE conducts multiple terrestrial field campaigns (Craters of the Moon National Monument and Preserve in Idaho for volcanics, and West Clearwater Impact Structure in Canada for impact studies) to study such features as analogs relevant to our moon, Phobos, Deimos, and asteroids. Here we present the science and exploration results from two deployments to Idaho (2014, 2015) and our first deployment to Canada (2014). FINESSE was selected as a research team by NASA's Solar System Exploration Research Virtual Institute (SSERVI). SSERVI is a joint effort by NASA's Science Mission Directorate (SMD) and Human Exploration and Operations Mission Directorate (HEOMD)

    Direct 2D spatial coherence determination using the Fourier analysis method Multi parameter characterization of the P04 beamline at PETRA III

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    We present a systematic 2D spatial-coherence analysis of the soft-X-ray beamline P04 at PETRA III for various beamline configurations. The influence of two different beam-defining apertures on the spatial coherence properties of the beam is discussed and optimal conditions for coherence-based experiments are found. A significant degradation of the spatial coherence in the vertical direction has been measured and sources of this degradation are identified and discussed. The Fourier-analysis method, which gives fast and simple access to the 2D spatial coherence function of the X-ray beam, is used for the experiment. Here, we exploit the charge scattering of a disordered nanodot sample allowing the use of arbitrary X-ray photon energies with this method

    Friction reduction and zero wear for 52100 bearing steel by high‐dose implantation of carbon

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    Ion implantation of carbon in the AISI 52100 bearing steel yields a distinct reduction in friction and wear. This improvement is strongly dependent on the implanted fluence. The coefficient of friction decreases from 0.6 to 0.2 for doses >1×1018 cm-2 (energy 100 keV) and a wear reduction to nearly ‘‘zero wear’’ was obtainable even under severe wear conditions. The counterpart (unimplanted AISI 52100 steel ball) shows a similar behavior, which demonstrates that the tribological system is totally changed. Mössbauer spectroscopy and x-ray diffraction revealed that hexagonal ¿-carbide is formed on implantation. On the other hand, Rutherford backscattering spectrometry shows that for high doses a large fraction of the implanted carbon is not contained in this carbide

    Overview of NASA Finesse (Field Investigations to Enable Solar System Science and Exploration) Science and Exploration Project

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    NASA's FINESSE (Field Investigations to Enable Solar System Science and Exploration) project was selected as a research team by NASA's Solar System Exploration Research Virtual Institute (SSERVI). SSERVI is a joint Institute supported by NASA's Science Mission Directorate (SMD) and Human Exploration and Operations Mission Directorate (HEOMD). As such, FINESSE is focused on a science and exploration field-based research program to generate strategic knowledge in preparation for human and robotic exploration of other planetary bodies including our Moon, Mars moons Phobos and Deimos, and near-Earth asteroids. FINESSE embodies the philosophy that "science enables exploration and exploration enables science"

    Megahertz-rate ultrafast X-ray scattering and holographic imaging at the European XFEL

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    The advent of X-ray free-electron lasers (XFELs) has revolutionized fundamental science, from atomic to condensed matter physics, from chemistry to biology, giving researchers access to X-rays with unprecedented brightness, coherence and pulse duration. All XFEL facilities built until recently provided X-ray pulses at a relatively low repetition rate, with limited data statistics. Here, results from the first megahertz-repetition-rate X-ray scattering experiments at the Spectroscopy and Coherent Scattering (SCS) instrument of the European XFEL are presented. The experimental capabilities that the SCS instrument offers, resulting from the operation at megahertz repetition rates and the availability of the novel DSSC 2D imaging detector, are illustrated. Time-resolved magnetic X-ray scattering and holographic imaging experiments in solid state samples were chosen as representative, providing an ideal test-bed for operation at megahertz rates. Our results are relevant and applicable to any other non-destructive XFEL experiments in the soft X-ray range

    Department of Animal Sciences research and reviews: beef and sheep

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    Relationship of a PCR-SSCP at the Bovine calpastatin locus with calpastatin activity and meat tenderness / H. Y. Chung, M. E. Davis, H. C. Hines, and D. M. Wulf -- Effects of calpain proteolysis and calpain genotypes on meat tenderness of angus bulls / H. Y. Chung, M. E. Davis, H. C. Hines, and D. M. Wulf -- Identification of genetic markers for growth and carcass traits in beef cattle / W. Ge, M. E. Davis, H. C. Hines, and K. M. Irvin -- Relationships of polymorphisms in the bovine leptin gene with differences in beef carcass traits / K. Tessanne, H. C. Hines, and M. E. Davis -- Effects of rate of gain during periods of restricted intake on performance and carcass characteristics in steers fed to achieve step-wise increases in rate of gain / J. E. Rossi and S. C. Loerch -- Effects of feeding regimen and days fed on performance and carcass characteristics of feedlot steers / J. E. Rossi, S. C. Loerch, S. J. Moeller, and J. P. Schoonmaker -- Effect of an accelerated finishing program on performance and carcass characteristics of early weaned bulls and steers / J. P. Schoonmaker, S. C. Loerch, F. L. Fluharty, T. B. Turner, S. J. Moeller and J. E. Rossi -- Yeast-mineral mixes and beef-cattle performance in fescue-based grazing systems: preliminary report / S. Boyles, W. Shriver, and D. Kobs -- Forage and animal evaluation of heifers at Indian Lake Hydrologic Unit CRP stocker grazing demonstration / S. L. Boyles, B. W. Stoll, and T. L. Dobbels -- Beef quality is every cattleman's business: education program / J. Yates and S. Boyles -- Effects of pelleted alfalfa and whole-shelled corn combinations on lamb growth and carcass characteristics / F. L. Fluharty -- Effects of feeding pelleted, ensiled, or a combination of pelleted and ensiled alfalfa on lamb growth and carcass characteristics / F. L. Fluharty, G. D. Lowe, and D. D. Clevenger -- Effects of corn silage vs. alfalfa haylage on lamb growth and carcass characteristics in forage-based finishing systems / F. L. Fluharty, G. D. Lowe, and D. D. Clevenger -- Effects of feed-delivery system and corn processing on lamb growth and carcass characteristics / F. L. Fluharty, G. D. Lowe, and D. D. Clevenger -- Effects of pen floor type and bedding on lamb growth and carcass characteristics / F. L. Fluharty, G. D. Lowe, and D. D. Clevenger -- A PCR-SSCP polymorphism detected in the 5' flanking region of the ovine IGF-I gene / A. Yilmaz, M. E. Davis, and H. C. Hine

    Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

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    Lawson criterion for ignition exceeded in an inertial fusion experiment

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    For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion
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