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991.
992.
A perturbative approach is developed to determine, term by term, the contributions of the various forces to the excimer potentials of the singlet and triplet excimers. The results show that the singlet excimer of naphthalene is more stable than the corresponding triplet excimer primarily due to large contributions of the exciton-resonance and the dispersion energy terms. The variation of the various terms with the conformations of the excimers suggests that the singlet and triplet excimers of naphthalene cannot have identical structure. 相似文献
993.
考虑夸克粒子间相互作用,研究了在准粒子近似下奇异夸克物质系统的热力学,发现由于热力学自洽的要求,需要在热力学势中额外增加一项.利用这一等效热力学讨论奇异夸克物质的物态方程及声速,得到了一个“软化”的物态,这与质量–密度相关模型是一致的.但准粒子描述模型能够显示介质效应对强相互作用耦合常数的依赖. 相似文献
994.
本文根据笔者设计的“双星实验”,分析了运动光源与观测者之间的红(紫)移规律,指出光波不等于声波,多普勒方程不能无限制的外推,否则将发生“错位”。 相似文献
995.
V. V. Sapunov 《Journal of Applied Spectroscopy》2001,68(2):243-250
The quenching of the triplet state of a number of Pd porphyrins and chlorophyll a by other complexes of porphyrins with Pd and Fe in liquid solutions was investigated with the use of pulsed photoexcitation. It is shown that the experimental data are consistent with the results of a kinetic analysis of the mechanism of quenching of the triplet state through the formation of excited complexes of interacting molecules. On the basis of analytical and experimental data, the probability values of intermolecular tripletstate energy transfer have been determined: K
ET = 2·1043·105 sec–1. A conclusion about the character of the excited complexes has been drawn; in particular, the distance between the molecules in the complexes has been estimated to be 5 . 相似文献
996.
We consider Kontsevich star products on the duals of Lie algebras. Such a star product is relative if, for any Lie algebra, its restriction to invariant polynomial functions is the usual pointwise product. Let
be a fixed Lie algebra. We shall say that a Kontsevich star product is
-relative if, on
*, its restriction to invariant polynomial functions is the usual pointwise product. We prove that, if
is a semi-simple Lie algebra, the only strict Kontsevich
-relative star products are the relative (for every Lie algebras) Kontsevich star products. 相似文献
997.
The purpose of this Letter is to propose an invariant for a G-invariant star product on a G-transitive symplectic manifold which remains invariant under the G-equivalence maps. This invariant is defined by using a quantum moment map which is a quantum analogue of the moment map on a Hamiltonian G-space. On S
2 regarded as an SO(3) coadjoint orbit in
, we give an example of this invariant for the canonical G-invariant star product. In this example, there arises a nonclassical term which depends only on a class of G-invariant star products. 相似文献
998.
Following the ideas presented in q-alg/9709040, we give the definition of Kontsevich star products for linear Poisson structures on d. We prove that all these structures are equivalent and can be defined by integral formulae. Finally, we characterize, among these star products, the Gutt and Duflo star products. 相似文献
999.
Heuzé K Méry D Gauss D Blais JC Astruc D 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(16):3936-3944
A series of bis(tert-butylphosphine)- and bis(cyclohexylphosphine)-functionalized Pd(II) monomers and polyamino (DAB) dendritic catalysts were synthesized and investigated for Sonogashira carbon-carbon coupling reactions in a copper-free procedure. The influence of phosphine substituents (tBu versus Cy) on the reaction kinetics was investigated by a GPC technique to monitor the reactions. The dendritic catalysts containing the cyclohexylphosphine ligands could be recovered and reused without loss of efficiency until the fifth cycle. The dendritic Pd(II) catalysts show a negative dendritic effect, that is, the catalyst efficiency decreases as the dendrimer generation increases. 相似文献
1000.