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961.
S. Yu. Ketkov H. L. Selzle E. W. Schlag S. N. Titova L. V. Kalakutskaya 《Optics and Spectroscopy》2004,97(4):567-571
Two-color photoionization of nickelocene molecules cooled in a supersonic jet is performed using a tunable nanosecond pulsed laser. The first stage of the multiphoton excitation is the transition from the highest occupied molecular orbital of nickelocene to the lowest Rydberg level. Conditions are found under which molecular ions (η 5-C5H5)2Ni+ are the only product of the multiphoton ionization in the one-color experiment. Irradiation of an excited molecule by an intense pulse of another laser increases significantly the yield of molecular ions. The dependence of the yield of (η5-C5H5)2Ni+ ions on the frequency of the second laser makes it possible to determine the adiabatic ionization potential of nickelocene as 6.138±0.012eV. 相似文献
962.
Statics of elasto-plastic media is stated in terms of eigenstrains acting upon a background elastic problem with fixed (initial) stiffness. In order to minimize the number of unknowns and to provide computationally cheap algorithms plastic multipliers are used as main driving variables. Fixed-point type iterations are suggested for computing plastic multipliers within the load increment. Numerical experiments results are shown to be in good correlation with other software results. A range of problems is outlined where the usage of the proposed algorithms can be advantageous. 相似文献
963.
964.
A number of fast computer procedures are described to find the minimum error vectors for observations of patients with cranial-cerebral traumas of a special type. 相似文献
965.
An expression is obtained for the reflection coefficient of circularly polarized light normally incident on the film of a cholesteric liquid crystal with a variable helix pitch. It is shown that, in the case of a single defect (local change in the helix pitch), the spectrum of light reflection from a cholesteric acquires a dip corresponding to the defect mode. New qualitative features appear in the reflection spectrum of a cholesteric with two defects as the distance between them varies. 相似文献
966.
967.
Mathematical Notes - 相似文献
968.
969.
Gatiyatullina G. V. Battalov E. M. Voloshin A. I. Prochukhan Yu. A. 《Russian Journal of Applied Chemistry》2003,76(4):626-628
Luminophores, 4,4'-diaminodiphenylmethane and Oxazine-17, were introduced into a photopolymerizable formulation based on an epoxy-acrylate oligomer, and their behavior in thin-film polymerization was studied. 相似文献
970.
V. V. Kuznetsov Yu. V. Ermolenko A. Ya. Zheltov K. A. Kornev S. V. Sheremet'ev 《Journal of Analytical Chemistry》2004,59(1):17-22
The coprecipitation of azo compounds based on 4-nitrophenyl- and 4-sulfophenyldiazonium naphthol sulfonates as their diphenylguanidinium ion-pair complexes with analogous compounds of naphthalene-2-sulfonic acid and 4-phenylsulfodiazonium is investigated. The optimization of the coprecipitation is considered based on the notions of the driving force of the cocrystallization of impurities. The optical characteristics of colored ion-pair complexes are measured. It is found that the water solubility is decreased most substantially for azosulfonates with hydrophobic nitro groups and with no more than two sulfo groups in different aromatic nuclei, which can lead to a decrease in the detection limit due to preconcentration by coprecipitation, which stimulates the thermodynamic flux of concentrate elution. Coprecipitation is combined with flow-injection analysis in the on-line mode, and new procedures are developed for determining naphthol sulfonates and related azo compounds with the detection limit equal to 0.003–0.006 mg/50 mL. 相似文献