8,604 research outputs found

    ANALYSIS OF CERVICAL SPINE INJURY RISK IN SPORTS USING FINITE ELEMENT METHOD

    Get PDF
    INTRODUCTION: Approximately 10,000 cervical spine injuries occur annually in the United States, with about 1,000 of these injuries resulting from sport-related events (Davis & McKelvey, 1998). In this study, we developed and validated the finite element model of cervical spine, and analyzed cervical spine injury risk using the model

    Momentum dependence of the N to Delta transition form factors

    Full text link
    We present a new method to determine the momentum dependence of the N to Delta transition form factors and demonstrate its effectiveness in the quenched theory at β=6.0\beta=6.0 on a 323×6432^3 \times 64 lattice. We address a number of technical issues such as the optimal combination of matrix elements and the simultaneous overconstrained analysis of all lattice vector momenta contributing to a given momentum transfer squared, Q2Q^2.Comment: Talk presented at Lattice 2004 (spectrum), Fermilab, 21-26 Jun. 2004. 3 pages, 3 figures. One typo in phenomenological Ansatz correcte

    Silica nanoparticles as a highly efficient catalyst for the one-pot synthesis of sterically congested 2-(dibenzylamino)-2-aryl acetamide derivatives from by phthaldehyde isomers, isocyanides and dibenzylamine

    Get PDF
    A green and efficient method for the preparation of 2-(dibenzylamino)-2-aryl acetamide derivatives via a three-component reaction of an isocyanide, dibenzylamine and a phthalaldehyde derivative in the presence of silica nanoparticles (silica NPs, ca. 42 nm) as a catalyst under solvent free conditions at room temperature is described. The ease of work-up, green chemistry conditions and high yields of the products make this procedure a useful addition to modern synthetic methods. The silica nanoparticles that used in this reaction as a catalyst were prepared by thermal decomposition of rice hulls. Simple, green and cheap method for the preparation of the nanocatalyst represents a major advantage for this process. The structures of these compounds were confirmed by IR, 1H and 13C NMR spectroscopy. KEY WORDS: Silica nanoparticles, Nanocatalyst, Isocyanide, Phthalaldehyde Bull. Chem. Soc. Ethiop. 2016, 30(3), 413-420DOI: http://dx.doi.org/10.4314/bcse.v30i3.

    Pulse-shape discrimination between electron and nuclear recoils in a NaI(Tl) crystal

    Get PDF
    We report on the response of a high light-output NaI(Tl) crystal to nuclear recoils induced by neutrons from an Am-Be source and compare the results with the response to electron recoils produced by Compton scattered 662 keV Îł\gamma-rays from a 137^{137}Cs source. The measured pulse-shape discrimination (PSD) power of the NaI(Tl) crystal is found to be significantly improved because of the high light output of the NaI(Tl) detector. We quantify the PSD power with a quality factor and estimate the sensitivity to the interaction rate for weakly interacting massive particles (WIMPs) with nucleons, and the result is compared with the annual modulation amplitude observed by the DAMA/LIBRA experiment. The sensitivity to spin-independent WIMP-nucleon interactions based on 100 kgâ‹…\cdotyear of data from NaI detectors is estimated with simulated experiments, using the standard halo model.Comment: 11page
    • …
    corecore