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91.
P. M. Borodin N. S. Golubev G. S. Denisov Yu. A. Ignatiev 《Magnetic resonance in chemistry : MRC》1975,7(4):185-186
The 1H NMR spectra of 1,1-dinitroethane/n-dibutylamine solutions in CCl4 have been investigated. It is shown that two types of complexes, the CH … N hydrogen bond complex and the ion pair are present in the solution simultaneously, with slow exchange through proton transfer between them. The exchange rates, activation energy and enthalpy of proton transfer are determined. It can be concluded that the act of proton transfer from carbon to nitrogen and back is kinetically determined. 相似文献
92.
93.
A. N. Borodin 《Journal of Mathematical Sciences》1988,43(6):2751-2764
Results are found on weak convergence of some processes generated by a recurrent random walk to a Brownian local time process.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 158, pp. 14–31, 1987. 相似文献
94.
95.
96.
We obtain size estimates for the distribution function of the bilinear Hilbert transform acting on a pair of characteristic
functions of sets of finite measure, that yield exponential decay at infinity and blowup near zero to the power −2/3 (modulo
some logarithmic factors). These results yield all known Lp bounds for the bilinear Hilbert transform and provide new restricted weak type endpoint estimates on Lp1 × Lp2 when either 1/p1 + 1/p2 = 3/2 or one of p1, p2 is equal to 1. As a consequence of this work we also obtain that the square root of the bilinear Hilbert transform of two
characteristic functions is exponentially integrable over any compact set. 相似文献
97.
A quantum chemistry study of Li(+) interactions with ethers, carbonates, alkanes, and a trifluoromethanesulfonylimide anion (TFSI(-)) was performed at the MP2, B3LYP, and HF levels using the aug-cc-pvDz basis set for solvents and TFSI(-) anion, and [8s4p3d/5s3p2d]-type basis set for Li. A classical many-polarizable force field was developed for the LiTFSI salt interacting with ethylene carbonate (EC), gamma-butyrolactone (GBL), dimethyl carbonate (DMC), acetone, oligoethers, n-alkanes, and perfluoroalkanes. Molecular dynamics (MD) simulations were performed for EC/LiTFSI, PC/LiTFSI, GBL/LiTFSI, DMC/LiTFSI, 1,2-dimethoxyethane/LiTFSI, pentaglyme/LiTFSI, and poly(ethylene oxide) (MW = 2380)/LiTFSI electrolytes at temperatures from 298 to 423 K and salt concentrations from 0.3 to 5 M. The ion and solvent self-diffusion coefficients, electrolyte conductivity, electrolyte density, LiTFSI apparent molar volumes, and structure of the Li(+) cation environment predicted by MD simulations were found in good agreement with experimental data. 相似文献
98.
Höfft O Borodin A Kahnert U Kempter V Dang LX Jungwirth P 《The journal of physical chemistry. B》2006,110(24):11971-11976
Surface segregation of iodide, but not of fluoride or cesium ions, is observed by a combination of metastable impact electron spectroscopy (MIES) and ultraviolet photoelectron spectroscopy (UPS(HeI)) of amorphous solid water exposed to CsI or CsF vapor. The same surface ionic behavior is also derived from molecular dynamics (MD) simulations of the corresponding aqueous salt solutions. The MIES results show the propensity of iodide, but not fluoride, for the surface of the amorphous solid water film, providing thus strong evidence for the suggested presence of heavier halides (iodide, bromide, and to a lesser extent chloride) at the topmost layer of aqueous surfaces. In contrast, no appreciable surface segregation of ions is observed in methanol, neither in the experiment nor in the simulation. Furthermore, the present results indicate that, as far as the thermodynamic aspects of solvation of alkali halides are concerned, amorphous solid water and methanol surfaces behave similarly as surfaces of the corresponding liquids. 相似文献
99.
Penning ionization of phenylacetylene and diphenylacetylene upon collision with metastable He*(2(3)S) atoms was studied by collision-energy-/electron-energy-resolved two-dimensional Penning ionization electron spectroscopy (2D-PIES). On the basis of the collision energy dependence of partial ionization cross-sections (CEDPICS) obtained from 2D-PIES as well as ab initio molecular orbital calculations for the approach of a metastable atom to the target molecule, anisotropy of interaction between the target molecule and He*(2(3)S) was investigated. For the calculations of interaction potential, a Li(2(2)S) atom was used in place of He*(2(3)S) metastable atom because of its well-known interaction behavior with various targets. The results indicate that attractive potentials localize in the pi regions of the phenyl groups as well as in the pi-conjugated regions of the acetylene group. Although similar attractive interactions were also found by the observation of CEDPICS for ionization of all pi MOs localized at the C[triple bond]C bond, the in-plane regions have repulsive potentials. Rotation of the phenyl groups about the C[triple bond]C bond can be observed for diphenylacetylene because of a low torsion barrier. So the examination of measured PIES was performed taking into consideration the change of ionization energies for conjugated molecular orbitals. 相似文献
100.
Mousavi SH Khanikaev AB Neuner B Avitzour Y Korobkin D Ferro G Shvets G 《Physical review letters》2010,105(17):176803
Highly confined "spoof" surface plasmons (SSPs) are theoretically predicted to exist in a perforated metal film coated with a thin dielectric layer. Strong modes confinement results from the additional waveguiding by the layer. Spectral characteristics, field distribution, and lifetime of these SSPs are tunable by the holes' size and shape. SSPs exist both above and below the light line, offering two classes of applications: "perfect" far-field absorption and efficient emission into guided modes. It is experimentally shown that these plasmonlike modes can turn thin, weakly absorbing semiconductor films into perfect absorbers. 相似文献