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91.
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93.
V. I. Avdeev E. A. Shugam S. D. Nasirdinov 《Theoretical and Experimental Chemistry》1972,5(5):396-402
The molecules of acetylacetone, benzoylacetone, dibenzoylmethane, and thiodibenzoylmethane have been calculated by the simple MO LCAO method and their absorption spectra recorded. The chelation of acetylacetone with a hydrogen atom does not affect the energy of the first allowed transition 1A1-1B1. Calculations correctly predict the change in the energy for this transition in the -diketone series: acetylacetone > benzoylacetone > dibenzoylmethane > thiodibenzoylmethane; the intensity reaches a maximum value for dibenzoylmethane and dropping sharply for thiodibenzoylmethane. The secondary absorption bands for benzoylacetone and dibenzoylmethane are examined experimentally and interpreted theoretically. 相似文献
94.
Ivan L. Dukov Georgi I. Kassabov Afaf F. Al-Nimri 《Monatshefte für Chemie / Chemical Monthly》1983,114(3):273-276
Solvent extraction of Pr, Gd and Yb with mixtures of HTTA andTOA has been investigated. The values of the synergistic equilibrium constant have been calculated. Some tendencies of the synergistic extraction of lanthanides have been discussed.
Einige Tendenzen in der synergistischen Extraktion von Lanthaniden mit einer Mischung aus Thenoyltrifluoraceton und Trioctylamin (Kurze Mitteilung)
Zusammenfassung Es wurde die synergistische Extraktion von Pr, Gd und Yb mit einer Mischung aus HTTA undTOA untersucht. Die synergistishcen Gleichgewichtskonstanten wurden berechnet und die Auswirkungen spezifischer Versuchsbedingungen auf das Extraktionsgleichgewicht diskutiert.相似文献
95.
We calculate the ξ-scaling corrections to xnyk moments inclusive lepton-hadron cross sections at fixed incident lepton energy. 相似文献
96.
N.E. Sorokina D.V. Savchenko S.G. Ionov A.S. Tikhomirov I.V. Nikol'skaya V.V. Avdeev 《Journal of Physics and Chemistry of Solids》2010,71(4):499-502
Here we report a physicochemical investigation of low-density carbon materials modified with pyrolytic carbon (PC). Exfoliated graphite (EG) obtained by nitrate expandable graphite thermal destruction was pressed into low-density graphite materials (LDGMs) with densities of 0.045-0.50 g/cm3 and saturated with PC by impact CVI technique. LDGM infiltration with PC leads to sample weight and density growth. The amount of deposited PC strictly depends on synthesis conditions. The maximum surface and volume deposition of PC occurred for samples with density of 0.05 g/cm3. XRD, Raman spectroscopy and scanning electron microscopy revealed that the deposited PC is of smooth laminar (SL) type. Composite thermal conductivity is about 2-3.5 Wt/m K. 相似文献
97.
98.
In this work we propose a method to study a weak exponential stability for time-varying differential inclusions applying an averaging procedure to a first approximation. Namely, we show that a weak exponential stability of the averaged first approximation to the differential inclusion implies the weak exponential stability of the original time-varying inclusion. The result is illustrated by an example. 相似文献
99.
A system of autonomous differential equations with a stable limit cycle and perturbed by small white noise is analyzed in this work. In the vicinity of the limit cycle of the unperturbed deterministic system, we define, construct, and analyze the Poincaré map of the randomly perturbed periodic motion. We show that the time of the first exit from a small neighborhood of the fixed point of the map, which corresponds to the unperturbed periodic orbit, is well approximated by the geometric distribution. The parameter of the geometric distribution tends to zero together with the noise intensity. Therefore, our result can be interpreted as an estimate of the stability of periodic motion to random perturbations. In addition, we show that the geometric distribution of the first exit times translates into statistical properties of solutions of important differential equation models in applications. To this end, we demonstrate three distinct examples from mathematical neuroscience featuring complex oscillatory patterns characterized by the geometric distribution. We show that in each of these models the statistical properties of emerging oscillations are fully explained by the general properties of randomly perturbed periodic motions identified in this paper. 相似文献
100.
Aleksey Tyazhev Georgi Marchev Valeriy Badikov Adolfo Esteban‐Martin Dmitrii Badikov Vladimir Panyutin Galina Shevyrdyaeva Svetlana Sheina Anna Fintisova Valentin Petrov 《Laser \u0026amp; Photonics Reviews》2013,7(4):L21-L24
The defect chalcopyrite crystal HgGa2S4 has been employed in a 1064‐nm pumped optical parametric oscillator operating at 100 Hz, to generate ∼5 ns long idler pulses near 4 µm with energies as high as 6.1 mJ and average power of 610 mW. At crystal dimensions comparable to those available for the commercial AgGaS2 crystal, operation of the 1064‐nm pumped HgGa2S4 OPO is characterized by much lower pump threshold and higher conversion efficiency, with the most important consequence that such a device might become practical at pump levels sufficiently lower than the optical damage threshold. 相似文献