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81.
Yu. M. Yukhin A. I. Titkov O. A. Logutenko K. V. Mishchenko N. Z. Lyakhov 《Russian Journal of General Chemistry》2017,87(12):2870-2874
The extraction of copper, silver, bismuth, and nickel with carboxylic acids thus providing concentrated metal-containing organic solutions and their crystalline salts has been studied. Micron- and submicron-sized metal powders have been obtained via reduction of these metals carboxylates by heating in benzyl alcohol or ethylene glycol. The synthesis of aspherical silver nanoparticles has been achieved by the reduction of a liquid extract of silver neodecanoate in benzyl alcohol. The possibility of the use of concentrated silver-containing solutions as inks for obtaining of electroconductive images has been demonstrated. 相似文献
82.
Using the Monte Carlo method, we address the influence of the Wiener and Poisson random noises on the behavior of oscillatory solutions to systems of stochastic differential equations (SDEs). For the linear and Van der Pol oscillators, we study the accuracy of estimates of the functionals of numerical solutions to SDEs obtained by the generalized explicit Euler method. For a linear oscillator, we obtain the exact analytical expressions for the mathematical expectation and the variance of the SDE solution. These expressions allow us to investigate the dependence of the accuracy of estimates of the solution moments on the values of SDE parameters, the size of meshsize, and the ensemble of simulated trajectories of the solution. For the Van der Pol oscillator, we study the dependence of the frequency and the damping rate of the oscillations of the mathematical expectation of SDE solution on the values of parameters of the Poisson component. The results of the numerical experiments are presented. 相似文献
83.
Artem N. Shevlyakov 《代数通讯》2017,45(9):3757-3767
A semigroup S is called an equational domain if any finite union of algebraic sets over S is algebraic. We give some necessary and su?cient conditions for a completely simple semigroup to be an equational domain. 相似文献
84.
Bahadur V Mishchenko L Hatton B Taylor JA Aizenberg J Krupenkin T 《Langmuir : the ACS journal of surfaces and colloids》2011,27(23):14143-14150
The prevention and control of ice accumulation has important applications in aviation, building construction, and energy conversion devices. One area of active research concerns the use of superhydrophobic surfaces for preventing ice formation. The present work develops a physics-based modeling framework to predict ice formation on cooled superhydrophobic surfaces resulting from the impact of supercooled water droplets. This modeling approach analyzes the multiple phenomena influencing ice formation on superhydrophobic surfaces through the development of submodels describing droplet impact dynamics, heat transfer, and heterogeneous ice nucleation. These models are then integrated together to achieve a comprehensive understanding of ice formation upon impact of liquid droplets at freezing conditions. The accuracy of this model is validated by its successful prediction of the experimental findings that demonstrate that superhydrophobic surfaces can fully prevent the freezing of impacting water droplets down to surface temperatures of as low as -20 to -25 °C. The model can be used to study the influence of surface morphology, surface chemistry, and fluid and thermal properties on dynamic ice formation and identify parameters critical to achieving icephobic surfaces. The framework of the present work is the first detailed modeling tool developed for the design and analysis of surfaces for various ice prevention/reduction strategies. 相似文献
85.
Artem A. Zemtsov Marina I. Struchkova Vladimir A. Tartakovsky 《Journal of fluorine chemistry》2011,132(6):378-381
The interaction of 2-nitrocinnamates with silicon reagents Me3SiRf (Rf = CF3, C2F5, and C6F5) promoted either by sodium acetate in DMF or by tetrabutylammonium acetate in dichloromethane has been described. The reactions proceed as conjugate addition of fluorinated carbanion at the CC bond and afford 3-aryl-2-nitrobutanoates bearing a fluorinated substituent in good yields as diastereomeric mixtures in ratio from 1:1 to 1.6:1. 相似文献
86.
利用基于扫描相机的荧光寿命成像显微技术研究细胞周期 总被引:2,自引:1,他引:1
利用基于扫描相机的荧光寿命成像显微系统,以细胞周期为模型,研究转染绿色荧光蛋白的HeLa细胞的荧光寿命。结果表明,处于周期内不同进程的细胞的荧光寿命为2.50~3.00 ns。处于分裂期的细胞的荧光寿命在1 h内从2.86 ns下降到2.82 ns;在DNA合成前期的8 h内,荧光寿命从2.82 ns下降到2.78 ns。荧光寿命的差异反映了细胞周期中核浆内大分子浓度的变化,对了解细胞周期的分子机制有一定的意义。 相似文献
87.
Mishchenko A Abdualla M Rudnev A Fu Y Pike AR Wandlowski T 《Chemical communications (Cambridge, England)》2011,47(35):9807-9809
As revealed for the first time by in situ scanning tunnelling spectroscopy (STS), ferrocene-modified Si(111) substrates show ambipolar field effect transistor (FET) behaviour upon electrolyte gating. 相似文献
88.
E. V. Mishchenko 《Russian Mathematics (Iz VUZ)》2011,55(1):19-32
In this paper we construct polynomials of a special type. We consider examples of their application for studying the convergence of special power series, for determining the upper and lower Riesz bounds for a basis consisting of B-splines, and for studying the convergence of a sequence of Battle-Lemarié scaling functions. 相似文献
89.
90.
V. V. Danilov M. V. Artem’ev A. V. Baranov G. M. Ermolaeva N. A. Utkina A. I. Khrebtov 《Optics and Spectroscopy》2008,105(2):306-309
The fluorescence of CdSe/ZnS nanorods in liquid-crystal and anisotropic polymer composites is studied. A high degree of the fluorescence anisotropy is shown. It is found that a solubilizer strongly affects the CdSe/ZnS orientation, which opens new possibilities for creating electrically controlled liquid-crystal composites. 相似文献