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991.
992.
We recorded vibrational spectra of the CO poison resulting from the electrochemical decomposition of CH3OH on platinum by sum-frequency generation using the infrared free electron laser CLIO. At high CH3OH concentration (0.1 M) in the electrolyte, both multi-bonded and linearly bonded CO are equally present. At lower CH3OH concentration (0.004 M), the multi-bonded species is predominant. The CO poison still remains on the surface at potentials (0.05 V/NHE) close to the hydrogen evolution onset.  相似文献   
993.
The literature on the synthesis of heterocyclic compounds from aliphatic nitro derivatives in the past decade has been summarized.Moscow State Textile Academy, 117918, Moscow. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1299–1336, October, 1994. Original article submitted October 6, 1994.  相似文献   
994.
We study the propagation of phase space singularities for the time dependent Schrödinger equation with potential having Coulomb-type singularities in space dimension equal tothree. We prove that the singularities (frequency set) of the solution are reflected by a Coulomb center exactly as in the classical problem, i.e. the frequency set follows theregularized trajectories of Classical Mechanics after a collision.  相似文献   
995.
We consider the application of the fictitious region method to solve the first and second boundary-value problems for a second-order quasilinear elliptical equation. Rate of convergence bounds are obtained for two versions of the fictitious region method.Translated from Vychislitel'naya i Prikladnaya Matematika, No. 56, pp. 7–14, 1985  相似文献   
996.
997.
998.
A new approach to calculating the temperatures of boiling at atmospheric pressure (T b) of organic compounds from arbitrary homologous series is suggested. The approach is based on the linear dependence of these values on T b for the preceding homologues, T b(n) = aTb(n ? 1) + b. This dependence, revealed for the first time, was used to obtain a recurrence relation for calculating T b of organic compounds within any series from the data on three simpler homologues of the same series. The mean a and b values can be used to estimate T b of an arbitrary organic compound from T b for one preceding homologue with an accuracy not inferior to that provided by the modern ACD software. Correlations of the general form P(n) = aP(n ? 1) + b are observed not only for the boiling points of organic compounds but also for their other properties P (refractive indexes, relative densities, and ionization energies). This opens up the possibility of creating unified algorithms for calculating various physicochemical constants of organic compounds instead of particular algorithms for every particular property known earlier.  相似文献   
999.
1000.
A theoretical framework is provided for generalizing the inferences drawn from the results of earlier experimental studies of kinetics of crystallization in oriented poly(ethylene terephthalate). The framework is obtained by combining extensions of classical nucleation theories in polymers3,4 and a theory of crystal growth with anisotropic incorporation of segments into growing crystals.15 It is shown that, while a very strong dependence of rate of primary nucleation on orientation does exist, there is a only a much weaker dependence of rate of crystal growth on the orientation of the crystallizing polymer. The theoretical formulation provided here would allow qualitative estimates for comparison with experiments.  相似文献   
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