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301.
Attila G. Császár Tamás Szidarovszky Nikolai F. Zobov Oleg L. Polyansky Jonathan Tennyson 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(9):1043-1106
A new, accurate, global, mass-independent, first-principles potential energy surface (PES) is presented for the ground electronic state of the water molecule. The PES is based on 2200 energy points computed at the all-electron aug-cc-pCV6Z IC-MRCI(8,2) level of electronic structure theory and includes the relativistic one-electron mass-velocity and Darwin corrections. For H216O, the PES has a dissociation energy of D0 = 41 109 cm−1 and supports 1150 vibrational energy levels up to 41 083 cm−1. The deviation between the computed and the experimentally measured energy levels is below 15 cm−1 for all the states with energies less than 39 000 cm−1. Characterization of approximate vibrational quantum numbers is performed using several techniques: energy decomposition, wave function plots, normal mode distribution, expectation values of the squares of internal coordinates, and perturbing the bending part of the PES. Vibrational normal mode labels, though often not physically meaningful, have been assigned to all the states below 26 500 cm−1 and to many more above it, including some highly excited stretching states all the way to dissociation. Issues to do with calculating vibrational band intensities for the higher-lying states are discussed. 相似文献
302.
The cathode–electrolyte interface in a solid oxide fuel cell is examined to understand why premature delamination is observed in alumina substituted YSZ electrolyte. From XRD, SEM and TEM observations it was concluded that after high temperature sintering a tetragonal (Mn,Al)3O4 forms at the interface, which during prolonged fuel cell operation forms a cubic (Mn,Al)3O4 phase. This transformation is associated with volume decrease creating voids which ultimately weaken the cathode–electrolyte interface sufficiently for the cathode layer to delaminate off the YSZ–Al2O3 electrolyte. 相似文献
303.
We calculate direct gaugino pair production at hadron colliders at next-to-leading order of perturbative QCD, resumming simultaneously large logarithms in the small transverse-momentum and threshold regions to next-to-leading logarithmic accuracy. Numerical predictions are presented for transverse momentum and invariant mass spectra as well as for total cross sections and compared to results obtained at fixed order and with pure transverse-momentum and threshold resummation. We find that our new results are in general in good agreement with the previous ones, but often even more precise. 相似文献
304.
Matthew J. Hamer Jonathan A.D. Wattis Richard S. Graham 《ournal of non Newtonian Fluid Mechanics》2010,165(19-20):1294-1301
We present an analytically derived model for flow induced crystallization (FIC), based upon the recent Graham–Olmsted simulation. We use combinatorial techniques to calculate nucleation energy landscapes, which correctly predict simulation data. Applying both the analytic calculation and the simulation, we put forward a simple expression relating nucleation rate to polymer chain stretch. We also investigate bimodal blends, an important step to understanding polydisperse systems and eventually modeling industrial polymer melts. 相似文献
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A common generalization of two theorems on the face numbers of Cohen-Macaulay (CM, for short) simplicial complexes is established:
the first is the theorem of Stanley (necessity) and Bj?rner-Frankl-Stanley (sufficiency) that characterizes all possible face
numbers of a-balanced CM complexes, while the second is the theorem of Novik (necessity) and Browder (sufficiency) that characterizes
the face numbers of CM subcomplexes of the join of the boundaries of simplices. 相似文献
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310.
Dr. Kim Søholm Halskov Dr. Howard S. Roth Prof. Dr. Jonathan A. Ellman 《Angewandte Chemie (International ed. in English)》2017,56(31):9183-9187
The first syntheses of privileged [5,6]-bicyclic heterocycles, with ring-junction nitrogen atoms, by transition metal catalyzed C−H functionalization of C-alkenyl azoles is disclosed. Several reactions are applied to alkenyl imidazoles, pyrazoles, and triazoles to provide products with nitrogen incorporated at different sites. Alkyne and diazoketone coupling partners give azolopyridines with various substitution patterns. In addition, 1,4,2-dioxazolone coupling partners yield azolopyrimidines. Furthermore, the mechanisms for the reactions are discussed and the utility of the developed approach is demonstrated by iterative application of C−H functionalization for the rapid synthesis of a patented drug candidate. 相似文献