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131.
M. Stone 《Physics letters. [Part B]》1977,67(2):186-188
We find a role for previously rejected unstable solitons. They describe processes by which a metastable vacuum state decays. Using these solutions we find a halflife for such states which agrees with that obtained by more restrictive methods. 相似文献
132.
All the methods so far proposed for deriving enthalpy-entropy relations fail to take into consideration the physical reasons for implied functional dependence between the activation parameters. In order to avoid spurious results it is essential to establish first the physical basis upon which the variation in the specific reaction rate itself depends, and then to carry that information through to the enthalpy-entropy plane.The proposals made here are of general application for establishing valid functional enthalpy-entropy relations, whatever their form, and in this context linear correlations are merely a subset. 相似文献
133.
An iteration procedure based on the Numerov-Cooley method of numerical integration is proposed for the computation of the potential function parameters in a one-dimensional Schrödinger equation from the experimental energies. The procedure has been tested on a calculation of the parameters of a Morse potential function and has been applied to a determination of the parameters of a double-minimum potential for the inversion motion of NH3 and ND3. 相似文献
134.
135.
An effective inversion-rotation Hamiltonian has been developed for NH3 which avoids the necessity of having to include high powers of the inversion motion coordinate in the Taylor expansions of the potential energy and the inverse moment of inertia tensor. This nonrigid bender Hamiltonian describes the centrifugal distortion and the Coriolis interactions in the ground and excited inversion states. It also describes the inversion doublings in the ground and excited vibration-inversion states of ammonia. A least-squares procedure that includes the numerical integration of the Schrödinger wave equation has been used to determine the harmonic force field and the double-minimum inversion potential function for (14NH3, 15NH3) and for (14ND3 and 14NT3).The anomalous rotational dependence of the inversion doublings in the (±l) components of the v4 = 1 state of 14NH3 has been explained by the Coriolis interactions between v2=1, v4 = 1, v2 = 2, v2 = 1, v4 = 1, and v2 = 3 vibration-inversion states. 相似文献
136.
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138.
Refractive index profiles of several types of silica-based low-loss optical fibres have been measured by the surface reflection technique. When polished samples are used inaccurate data are obtained. For germanium- and phosphorus-doped samples good results are obtained using samples prepared by fracturing the end of the fibre. For borosilicate fibres rapid changes due to atmospheric exposure result in inaccurate data. 相似文献
139.
Aurelie Vandenbeuch Marco Tizzano Catherine B Anderson Leslie M Stone Daniel Goldberg Sue C Kinnamon 《BMC neuroscience》2010,11(1):77
Background
Glutamate has been proposed as a transmitter in the peripheral taste system in addition to its well-documented role as an umami taste stimulus. Evidence for a role as a transmitter includes the presence of ionotropic glutamate receptors in nerve fibers and taste cells, as well as the expression of the glutamate transporter GLAST in Type I taste cells. However, the source and targets of glutamate in lingual tissue are unclear. In the present study, we used molecular, physiological and immunohistochemical methods to investigate the origin of glutamate as well as the targeted receptors in taste buds. 相似文献140.
Huang GS Miller DH Pavlunin V Sanghi B Shipsey IP Adams GS Cravey M Cummings JP Danko I Napolitano J He Q Muramatsu H Park CS Thorndike EH Coan TE Gao YS Liu F Artuso M Boulahouache C Blusk S Butt J Dorjkhaidav O Li J Menaa N Mountain R Nandakumar R Randrianarivony K Redjimi R Sia R Skwarnicki T Stone S Wang JC Zhang K Csorna SE Bonvicini G Cinabro D Dubrovin M Briere RA Chen GP Chen J Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Adam NE Alexander JP Berkelman K Cassel DG Crede V 《Physical review letters》2006,96(3):032003
Using data collected at the psi(3770) resonance with the CLEO-c detector at the Cornell e+e- storage ring, we present searches for 25 charmless decay modes of the psi(3770), mostly multibody final states. No evidence for charmless decays is found. 相似文献