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Strongin B Bofill J Friedman JI Fuess S Goodman MC Kendall HW Kistiakowsky V Lyons T Osborne LS Pitt R Schneekloth U Taylor FE Bogert D Koizumi G Stutte L Abolins M Brock R Cobau W Hatcher R Owen D Perkins G Tartaglia M Weerts H Belusevic R Walker JK White A Womersley J 《Physical review D: Particles and fields》1991,43(9):2778-2786
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Tendon functions by transmitting tensile loads from muscle to bone. Morphologically, it can be described as a macromolecular multicomposite material, basically consisting of collagen fibrils held together by a soft, hydrated matrix material. Recently, tendon has been deformed beyond the "in vivo" elastic limit and by cyclical loading systematically damaged. Using high-resolution electron microscopy, decomposition of the collagen fibril into subfibrils (15 nm diameter) and microfibrils (3.5 nm diameter) has been noted. The interfacial adhesion between such units is strongly dependent on age, and is probably related with crosslinking phenomena observed by biochemical methods. In addition, tendon collagen contains a considerable amount of water throughout the entire structure which strongly affects its overall mechanical behavior. The various bound states of water have been identified using primarily dynamic mechanical spectroscopy coupled with more conventional methods of structural characterization.Published in Mekhanika Polimerov, No. 4, pp. 693–701, July–August, 1976. 相似文献
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We construct cup and cap products in intersection (co)homology with field coefficients. The existence of the cap product allows us to give a new proof of Poincaré duality in intersection (co)homology which is similar in spirit to the usual proof for ordinary (co)homology of manifolds. 相似文献
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Abstract Methyl acrylate in dimethyl sulfoxide was polymerized by 2537 A ultraviolet light. The photo reaction exhibited zero-order kinetics for a given initial concentration and produced short chain polymers (M[Mbar]W ~ 20,000). Low sulfur values of isolated polymers indicated no appreciable solvent incorporation during the polymerization. 相似文献
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In the last decades it was observed that Clifford algebras and geometric product provide a model for different physical phenomena. We propose an explanation of this observation based on the theory of bounded symmetric domains and the algebraic structure associated with them. The invariance of physical laws is a result of symmetry of the physical world that is often expressed by the symmetry of the state space for the system implying that this state space is a symmetric domain. For example, the ball of all possible velocities is a bounded symmetric domain. The symmetry on this ball follow from the symmetry of the space-time transformations between two inertial systems, which fixes the so-called symmetric velocity between them. The Lorenz transformations acts on the ball Sof symmetric velocities by conformal transformations. The ball Sis a spin ball (type IV in Cartan's classification). The Lie algebra of this ball is defined a triple product that is closely related to geometric product. The relativistic dynamic equations in mechanics and for the Lorenz force is described by this Lie algebra and the triple product. 相似文献