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71.
Truhlar DG Mead CA 《Physical chemistry chemical physics : PCCP》2011,13(10):4754-5; author reply 4756-8
A recent paper in this journal proposed the conversion of conical intersections to avoided crossings by lowering the symmetry with an optical field. The article also claimed that the characters of nonadiabatic transitions caused by avoided crossings and conical intersections are qualitatively different. The present comment shows that this proposal and this claim result from an incorrect appreciation of the nature of conical intersections and avoided crossings. Conical intersections are moved, not removed, by almost all perturbations. Furthermore, there is no dichotomy between avoided crossing mechanisms and conical intersection mechanisms; as the parameters of the problem change and the typical locally avoided crossing involved in nonadiabatic dynamics becomes farther from the conical intersection, there is a gradual shift in the nature of the nonadiabatic transitions, with a continuum of possible behaviors, not just two. 相似文献
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Kirti Patel Sudhir Kapoor D. P. Dave Tulsi Mukherjee 《Journal of Chemical Sciences》2005,117(1):53-60
Silver nanosized crystallites have been synthesized in aqueous and polyols viz., ethylene glycol and glycerol, using a microwave
technique. Dispersions of colloidal silver have been prepared by the reduction of silver nitrate both in the presence and
absence of stabilizer poly(vinylpyrolidone) (PVP). It was observed that PVP is capable of complexing and stabilizing Ag nanoparticles
formed through the reduction of Ag+ ions in water and ethylene glycol. In the case of ethylene glycol, it has been shown that the use of PVP leads to particles
with a high degree of stability. The colloids are stable in glycerol for months even in the absence of stabilizer. 相似文献
74.
The ground-state energy of 16O is calculated variationally for simple models of the bare two-nucleon interaction, assumping a correlated trial function of Jastrow type. The low odd-parity levels are determined by configuration mixing in a truncated basis of likewise-correlated one-particle-one-hole states. 相似文献
75.
A probabilistic inventory model for continuously deteriorating items is developed, in which the lead time is assumed to be of one scheduling period, shortages are not allowed, time is treated as discrete variable, and deterioration is assumed to be a constant fraction of the on hand inventory. The developed model is related to the EOQ model for deteriorating items. An example is given to illustrate the derived results. 相似文献
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Dave Pandres Jr. 《International Journal of Theoretical Physics》1984,23(9):839-842
The relativity principle that the law of propagation for light has the same form for all macroscopic observers is extended to include quantum observers; i.e., observers who may be large, but not infinitely large, by comparison with quantum mechanical systems. This leads to the extension of the covariance group from the diffeomorphisms to the conservation group (which is the largest group of coordinate transformations under which conservation laws are covariant statements) and, thus, to the quantum geometry and quantum unified field theory considered in a previous paper. 相似文献
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