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The evolution of charged‐particle production in collisions of heavy ions at relativistic energies is investigated as function of centrality in a nonequilibrium‐statistical framework. Precise agreement with recent d + Au and Au + Au data at = 200 GeV is found in a Relativistic Diffusion Model with three sources for particle production. Only the midrapidity source comes very close to local equilibrium, whereas the analyses of the overall pseudorapidity distributions show that the systems remain far from statistical equilibrium.  相似文献   
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Yang C  Nakamura A  Wada T  Inoue Y 《Organic letters》2006,8(14):3005-3008
[reaction: see text] A series of modified gamma-cyclodextrins (CDs) with a flexible or rigid cap, synthesized and used as chiral supramolecular hosts for mediating the enantiodifferentiating photocyclodimerization of 2-anthracenecarboxylic acid, significantly improved the chemical and optical yields of chiral head-to-head cyclodimer 3, while the gamma-CD with a rigid cap dramatically inverted the stereochemical outcomes and further improved the enantioselectivities of both head-to-tail and head-to-head dimers 2 and 3.  相似文献   
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We consider a Cauchy problem for a semilinear heat equation
(P)  相似文献   
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A quantum system of a Dirac particle interacting with the quantum radiation field is considered in the case where no external potentials exist. Then the total momentum of the system is conserved and the total Hamiltonian is unitarily equivalent to the direct integral of a family of self-adjoint operators acting in the Hilbert space , where is the Hilbert space of the quantum radiation field. The fiber operator is called the Hamiltonian of the Dirac polaron with total momentum . The main result of this paper is concerned with the non-relativistic (scaling) limit of . It is proven that the non-relativistic limit of yields a self-adjoint extension of a Hamiltonian of a polaron with spin 1/2 in non-relativistic quantum electrodynamics.  相似文献   
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Pure rotational spectra of S235Cl2 and S235Cl37Cl have been observed using a Fourier-transform microwave spectrometer. An analysis of the hyperfine structure made by considering the nuclear spin statistics showed that S2Cl2 has C2symmetry, where the hyperfine splittings due to the two Cl nuclei were analyzed precisely. The nuclear quadrupole coupling constants including the off-diagonal (χabχacχbc) components and the nuclear spin–rotation interaction constants associated with the two Cl nuclei have been determined for the first time. We have shown that the nuclear quadrupole interaction plays an important role in the orthopara mixing.  相似文献   
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We report here the first example of organic radical battery with DNA. Though there is a growing interest in DNA/cationic-lipid complexes as promising gene delivery vehicles, few efforts have been focused on the use of such complexes as advanced materials for organic optoelectronic applications. The present article describes how substitution of the sodium counter cation of DNA with cationic amphiphilic lipid(1-4) provided novel DNA-lipid complexes that contain TEMPO radicals, in which the actual mole ratio of phosphate to lipid was 1:0.84 to 1:0.16. All the TEMPO-containing DNA-lipid complexes displayed reversible two-stage charge/discharge processes, the discharge capacities of which were 40.5-60.0 A h kg(-1). In particular, the capacity of a DNA-lipid(3)-based cell reached 60.0 A h kg(-1), which corresponds to 192 % relative to its theoretical value for the single-electron one-stage process, indicating a two-electron process.  相似文献   
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