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Based on the analysis theory of random energy of train derailment, an analysis theory of random energy of train derailment in wind is suggested. Two methods are proposed -the time domain method and the frequency domain method of analysis theory of random energy of train derailment in wind. The curves of σ pw -v under various wind speeds are obtained through the computation. The original curve of σ p -v is expanded, which turns the analysis theory of random energy of train derailment into the all-weather theory. Train derailment condition has been established under wind action. The first and second criterions of train derailment have been proposed in light of wind action. The analysis of train derailment cases at home or abroad is made, in- cluding the first analysis of Xinjiang train derailment case encountered 13-level of gale, which explained the inevitability of train derailment. The analysis theory of random energy of train derailment in wind shows its validity and accuracy. The input energy σ pw of the transverse vibration of train-track(bridge)-wind system is linked to train speed. With the establishment of the analysis theory of random energy of train derailment in wind, It is likely to initiate an all-weather speed limit map for a train or any high-speed train.  相似文献   
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Crystals of {(Me(2)PhP)AuX}(n) (Me = methyl; Ph = phenyl; X = Cl, Br, I; n = 2, 3) show emission from two excited states. Both states are assigned a triplet multiplicity, on the basis of their lifetimes and zero-field splittings. The structured, higher energy emission originates at approximately 360 nm and has the greater relative intensity at low temperatures. It is assigned as intraligand phosphorescence from a phenyl-localized (3)pipi state. The unstructured, lower energy emission has a peak wavelength that varies in the range 630-730 nm. It is assigned as phosphorescence from the triplet state due to the gold-based sigma(p) <-- sigma(s,d) excitation. The corresponding singlet state is observed at 290-310 nm. The results of SCF-Xalpha-SW calculations on the model complexes H(3)PAuX and (H(3)PAuX)(2) are also presented.  相似文献   
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1 IntroductionInrecentyears,theintentionaloraccidentalreleaseofthechemicalwastesonsoilshasfurtherstimulatedcurrentinterestsinthemovementofchemicals.Displacementstudieshavebecomeimportanttoolsinsoilphysics,particularlyforpredictingthemovementofpestcides…  相似文献   
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The structures of the series of two-coordinate gold(I) complexes {(Me(2)PhP)AuX}(n) where X is Cl, Br, or I have been examined by X-ray diffraction. The chloro complex crystallized in two separate polymorphic forms. Colorless hexagonal blocks of {(Me(2)PhP)AuCl}(3) crystallized in the monoclinic space group P2(1)/m with a = 12.141(4) ?, b = 8.433(2) ?, c = 14.834(3) ?, and beta = 94.15(2) degrees at 130 K with Z = 2. Refinement of 2837 reflections and 177 parameters yielded R = 0.066 and R(w) = 0.069. The complex consists of three nearly linear P-Au-Cl units that are connected by Au-Au contacts at 3.091(2) and 3.120(2) ?. Colorless prisms of {(Me(2)PhP)AuCl}(2) form in the orthorhombic space group P2(1)2(1)2(1) as described earlier (Cookson, P. D.; Tiekink, E. R. T. Acta Crystallogr. 1993, C49, 1602). The two nearly linear P-Au-Cl units are staggered and connected through a Au-Au bond (3.230(2) ?). Colorless rectangular prisms of {(Me(2)PhP)AuBr}(2) form in the monoclinic space group P2(1) with a = 9.572(5) ?, b = 8.757(3), and c = 12.915(7) at 130 K with Z = 2. Refinement of 2469 reflections with 118 parameters yielded R = 0.080 and R(w) = 0.084. {(Me(2)PhP)AuI}(2) is isomorphous with the bromo complex with a = 9.736(2) ?, b = 8.890(2) ?, and c = 13.160(5) ? at 130 K with Z = 2. Refinement of 2796 reflections with 119 parameters yielded R = 0.052 and R(w) = 0.058. These complexes are similar to the chloro dimer but with altered orientations of the phenyl substituent. The predicted order of ligand effects (Cl > Br > I) on Au-Au distances from quasi-relativistic calculations is borne out in the experimental values: 3.230 ? (Cl); 3.119 ? (Br); 3.104 ? (I). In dichloromethane, these complexes dissociate into monomeric units but there is some evidence for the presence of dimers in concentrated solutions of the iodide compound.  相似文献   
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