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981.
John W. Tromp Robert J. Le Roy Simon Gerstenkorn Paul Luc 《Journal of Molecular Spectroscopy》1983,100(1):82-94
The disagreement of Danyluk and King's (Chem. Phys.25, 343 (1977)) rotational constants for levels lying near the dissociation limit of B-state I2 with the mechanical behavior predicted by near-dissociation theory is investigated. The discrepancies are shown to be much too large to be explained by either the neglect of centrifugal distortion effects in the original analysis or by rotational or spin-rotation coupling to a nearby repulsive 1u state. These differences are therefore attributed to experimental error, a conclusion which is confirmed by more recent experimental results. A reanalysis of the best available data for levels near the dissociation limit of B-state I2 then yields improved values for the B-state dissociation limit = 20 043.16 (±0.02) cm?1 of the vibrational index at dissociation v = 87.32 (±0.04) and of the long-range potential constant . This in turn implies a slightly improved ground-state dissociation energy of 0 = 12 440.18 (±0.02) cm?1. 相似文献
982.
Nonlinear Dynamics - Based on bifurcation theory, nonlinear frequency response analysis is a recent development in the field of flight dynamics studies. Here, we consider how this method can be... 相似文献
983.
Summary Si dà un teorema di esistenza e di unicità di soluzione generalizzata per il problema di Cauchy relativo all'equazione
. Le ipotesi fatte sui coefficienti ai(t, x) permettono discontinuità di tipo molto generale, purchè sia soddisfatta una certa «condizione di trasversalità» tra le caratteristiche dell'equazione e le discontinuità del campo di vettori che le definisce. 相似文献
984.
Barry Simon 《Journal of statistical physics》1985,38(1-2):65-76
We present, in an expository way, an elementary rigorous proof (patterned after an argument of Kirsch-Martinelli) that the Anderson model has Lifschitz tails in very great generality.Research partially supported by USNSF Grant No. MCS-81-20833. 相似文献
985.
Paul L. Coe Simon E. Sellers J.Colin Tatlow Graham Whittaker 《Journal of fluorine chemistry》1980,16(6):612
As part of a programme to prepare and evaluate a series of perfluoro- chemicals for use as inert fluids, the fluorinations of some tetrafluoroethylene oligomers over cobalt (III) fluoride have been studied.Fluorination of perfluoro-3,4-dimethylhex-3-ene (tetramer) and perfluoro-4-ethyl-3,4-dimethylhex-2-ene (pentamer) over CoF3 at 230°C and l45°C respectively afforded the corresponding saturated fluorocarbons however, at 250°C, pentamer gave predominantly the saturated tetramer. The thermal behaviour of these saturated fluorocarbons alone and in the presence of bromine and toluene has been studied.Pyrolysis of pentamer over glass beads at 500°C gave perfluoro-1,2,3- trimethylcyclobutene and isomers of perfluoro-2,3-dimethylpenta-1,3- diene. Under similar conditions perfluoro-2-(1-ethyl-1-methylpropyl). 3-methylpent-1-ene (hexamer) gave perfluoro-1-methyl-2-(1-methyl- propyl)-cyclobut-1-ene and perfluoro-2-methyl-3-(1-methylpropyl)-buta- 1,3-diene.These reactions and the structural elucidation of the products will be discussed. 相似文献
986.
Robert F. Brady Frederick E. Simon 《Journal of polymer science. Part A, Polymer chemistry》1987,25(1):231-239
New bicyclic and tricyclic compounds have been synthesized by the Lewis acid-catalyzed condensation of epoxides with cyclic acid anhydrides or cyclic bislactones. These materials take part in the anionic addition polymerization of amine-functional polyamides with diepoxides, and modify the shrinkage that is characteristic of the reaction. It is possible to control the extent of shrinkage by choosing an appropriate comonomer and by adjusting the concentration of this material in the reaction mixture. 相似文献
987.
Zeno Simon 《Angewandte Chemie (International ed. in English)》1974,13(11):719-727
Specific interactions or recognition processes are extremely important in many fields of chemistry and biology: typical examples are the enzyme-substrate and the antigen-antibody reactions. Quantitative predictions require a knowledge of steric fit, intermolecular forces, and molecular size. These considerations should facilitate design of new drugs. 相似文献
988.
Simon P. Eveson Vladimir D. Stepanov Elena P. Ushakova 《Mathematische Nachrichten》2015,288(8-9):877-897
An embedding inequality of Sobolev type is characterized in the paper with help of a duality principle and boundedness criteria for the Hardy–Steklov integral operator in weighted Lebesgue spaces. 相似文献
989.
Lau Cher Hon Cervini Raoul Clarke Stephen R. Markovic Milena Ginic Matisons Janis G. Hawkins Stephen C. Huynh Chi P. Simon George P. 《Journal of nanoparticle research》2008,10(1):77-85
Nanosized powders of Ti-Nb oxide core-shell nanocrystals with atomic ratios of Nb/Ti = 0.11, 0.25, and 0.38 have been prepared
by two preparation routes. The first route was co-precipitation, followed by␣annealing, using NbCl5 as a source of Nb. The second route was coating of pure TiO2 nanocrystals by Nb-isopropoxide in liquid medium, followed by impregnation of the Nb into the nanoparticles by annealing.
Both methods yielded anatase nanocrystals with a Nb-rich shell and a core, which had much lower Nb loadings. The anatase structure
solid solution (with Nb incorporated) was stable under annealing up to 760°C. The particle size remained within the nanometric
scale (<50 nm) under heat-treatment up to 760°C. It has been shown that the fabricated powders can be redispersed in aqueous media
by simple ultrasound treatment, resulting in nanosized dispersions. Using a variety of analytical techniques, including depth
profiling of single nanocrystallites by AES combined with sputtering by Ar ions, the mechanism of the core-shell structure
creation was studied. It is proposed that the formation of the core-shell structure is governed by solubility limitations
in the co-precipitation route and by solubility and diffusion limitations in the coating-incorporation route. 相似文献
990.
Mark W. Simon Jeffrey R. Rozak Steven L. Suib Jeffrey Harrison Mahmoud Kablauoi 《Research on Chemical Intermediates》2000,26(6):529-548
Pure hydrocarbon plasmas have been generated at low pressures with good efficiency using methane as a reactant. Hydrocarbon
plasma discharges containing high energy, free radical, and ionized intermediates were analyzed in situ using emission spectroscopy. Emission spectra were correlated with analytical data obtained from resultant product mixtures
and literature assignments of emission bands in order to identify these intermediates. Stabilization of atmospheric methane
plasmas using argon as a diluent has also been demonstrated in this study. Emission spectroscopy has also been used to identify
reaction intermediates formed in plasmas at high pressures. Distinct differences in plasma discharges have been observed as
a function of pressure, power, and methane concentrations at the molecular level using in situ spectroscopic techniques. 相似文献