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It is shown that double-orthogonal sets (diamonds) in Minkowski space form an orthomodular complete lattice. Connection with empirical logic of Randall and Foulis is discussed.  相似文献   
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Conserved currents are shown to define states on causal logic of Minkowski space.  相似文献   
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This work expands on the recent separation of the enantiomers of the C2-symmetrical bis-substituted derivatives of 1,1′-diphosphaferrocene. The effective separation of mono-substituted 1,1′-diphosphaferrocenes by the proposed method is demonstrated. The absolute configuration of the three separated components was established using X-ray diffraction. Circular dichroism spectra were collected for all of the separated compounds. The spectrum of each compound shows a characteristic curve, and the curves for the enantiomers are symmetrical. We also show that the correct absolute configuration for similar species can be assigned on the basis of the obtained data. We propose an explanation for the abnormal 1H NMR spectra of phospholyl protons in some derivatives of 1,1′-diphosphaferrocene. A density functional theory (DFT) study of the conformation, as well as circular dichroism and NMR spectra of the chosen species, is also presented.  相似文献   
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Analysis of the thermo-mechanical behavior of electrospun thermoplastic polyurethane (TPU) block co-polymer nanofibers (glass transition temperature ∼−50 °C) is presented. Upon heating, nanofibers began to massively contract, at ∼70 °C, whereas TPU cast films started to expand. Radial wide-angle X-ray scattering (WAXS) profiles of the nanofibers and the films showed no diffraction peaks related to crystals, whereas their amorphous halo had an asymmetric shape, which can be approximated by two components, associated with hard and soft segments. During heating, noticeable changes in the contribution of these components were only observed in nanofibers. These changes, which were accompanied with an endothermic DSC peak, coinciding with the start of the nanofibers contraction, can be attributed to relaxation of an oriented stretched amorphous phase created during electrospinning. Such structure relaxation becomes possible when a portion of the hard segment clusters, forming an effective physical network, is destroyed upon heating.  相似文献   
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We give the parameter version of a localization theorem for the Bergman metric near the boundary points of strictly pseudoconvex domains. The approximation theorem for square integrable holomorphic functions on such domains in the spirit of Graham-Kerzman is proved in the hereby paper, as well.  相似文献   
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It is shown that the point spectrum of internal symmetries is always symmetric. It is a group provided the intersection of all local subalgebras is trivial.  相似文献   
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