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71.
Ohne Zusammenfassung 相似文献
72.
73.
In this paper, a mixture representation for the joint distribution function of progressively Type-II censored order statistics from heterogeneous distributions is established. Applications of this representation to stochastic orderings and inequalities are then illustrated. 相似文献
74.
Benedikt Linke und Heinrich Preissecker 《Fresenius' Journal of Analytical Chemistry》1933,94(7-8):238-239
Ohne Zusammenfassung 相似文献
75.
R. Benedikt 《Fresenius' Journal of Analytical Chemistry》1884,23(1):267-269
Ohne Zusammenfassung 相似文献
76.
Conventional lattice Boltzmann models for the simulation of fluid dynamics are restricted by an error in the stress tensor that is negligible only for small flow velocity and at a singular value of the temperature. To that end, we propose a unified formulation that restores Galilean invariance and the isotropy of the stress tensor by introducing an extended equilibrium. This modification extends lattice Boltzmann models to simulations with higher values of the flow velocity and can be used at temperatures that are higher than the lattice reference temperature, which enhances computational efficiency by decreasing the number of required time steps. Furthermore, the extended model also remains valid for stretched lattices, which are useful when flow gradients are predominant in one direction. The model is validated by simulations of two- and three-dimensional benchmark problems, including the double shear layer flow, the decay of homogeneous isotropic turbulence, the laminar boundary layer over a flat plate and the turbulent channel flow. 相似文献
77.
Raphael F. Ribeiro Aleksandr V. Marenich Christopher J. Cramer Donald G. Truhlar 《Journal of computer-aided molecular design》2010,24(4):317-333
We applied the solvation models SM8, SM8AD, and SMD in combination with the Minnesota M06-2X density functional to predict
vacuum-water transfer free energies (Task 1) and tautomeric ratios in aqueous solution (Task 2) for the SAMPL2 test set. The
bulk-electrostatic contribution to the free energy of solvation is treated as follows: SM8 employs the generalized Born model
with the Coulomb field approximation, SM8AD employs the generalized Born approximation with asymmetric descreening, and SMD
solves the nonhomogeneous Poisson equation. The non-bulk-electrostatic contribution arising from short-range interactions
between the solute and solvent molecules in the first solvation shell is treated as a sum of terms that are products of geometry-dependent
atomic surface tensions and solvent-accessible surface areas of the individual atoms of the solute. On average, three models
tested in the present work perform similarly. In particular, we achieved mean unsigned errors of 1.3 (SM8), 2.0 (SM8AD), and
2.6 kcal/mol (SMD) for the aqueous free energies of 30 out of 31 compounds with known reference data involved in Task 1 and
mean unsigned errors of 2.7 (SM8), 1.8 (SM8AD), and 2.4 kcal/mol (SMD) in the free energy differences (tautomeric ratios)
for 21 tautomeric pairs in aqueous solution involved in Task 2. 相似文献
78.
Donoghue PJ Gupta AK Boyce DW Cramer CJ Tolman WB 《Journal of the American Chemical Society》2010,132(45):15869-15871
Insight into copper-oxygen species proposed as intermediates in oxidation catalysis is provided by the identification of a Cu(II)-superoxide complex supported by a sterically hindered, pyridinedicarboxamide ligand. A tetragonal, end-on superoxide structure is proposed based on DFT calculations and UV-vis, NMR, EPR, and resonance Raman spectroscopy. The complex yields a trans-1,2-peroxodicopper(II) species upon reaction with [(tmpa)Cu(CH(3)CN)]OTf and, unlike other known Cu(II)-superoxide complexes, acts as a base rather than an electrophilic (H-atom abstracting) reagent in reactions with phenols. 相似文献
79.
80.