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1.
Conclusion The proposed model of formation of the reinforcing framework in the manufacture of an axisymmetric shell by the CPW method makes it possible to numerically determine the thicknesses and rates of filling the layers, reinforcement angles as a function of the main parameters of the technological process, geometry of the mandrel, and characteristics of the reinforcing filament. It was established that the thicknesses of the layers, reinforcement rates and angles, and, as a consequence, the effective stiffness characteristics of the composite are substantially variable both along the meridian and over the thickness of the shell.Translated from Mekhanika Kompozitnykh Materialov, No. 5, pp. 609–617, September–October, 1992.The authors thank V. A. Frolov for the experimental results. 相似文献
2.
Results are presented of an analytic construction and investigation of adaptive data classification algorithms for intermittent turbulence. A decision making rule is presented, relationships are derived to estimate the classification accuracy. A three-level procedure is described for processing the intermittency, including the calculation algorithms for the initial point, self-teaching, and optimal classification. It is shown that the method proposed permits realization of total automation of intermittency data processing.Translated from Teoreticheskaya i Prikladnaya Mekhanika, No. 18, pp. 119–123, 1987. 相似文献
3.
B. F. Myasoedov L. A. Gribov A. I. Pavlyuchko I. V. Rybalchenko G. I. Sigeikin A. F. Kireev V. N. Suvorkin 《Journal of Structural Chemistry》2006,47(3):434-441
For highly toxic organophosphorus compounds on the limiting lists of the International Chemical Weapons Ban Treaty, fragment methods may be used for calculating their IR vibrational spectra; this is shown for O-alkyl alkylfluorophosphonates used as examples. The geometrical parameters and the parameters of the potential and electrooptic functions are found for the major fragments of these compounds. Due to this, fast predictive computation of IR spectra of O-alkyl alkylfluorophosphonates is possible, the accuracy of calculation being sufficient for spectral identification of these compounds; a database of the calculated IR spectra may be created. 相似文献
4.
Yu. P. Zaspa S. V. Kireev E. D. Protsenko V. K. Veselov V. K. Isupov 《Journal of Applied Spectroscopy》1992,56(1):88-92
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 56, No. 1, pp. 116–121, January, 1992. 相似文献
5.
6.
Wiesław Sulkowski Anna Sułkowska Viatsheslav Kireev 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract The presence of trace of chlorine in poly(diorganophosphazenes) [-N=P(OR)2-]., where R = C2H5, CH2CF3, C2F5, C4H5, C6H13, C8H17, C12H25, CH2C6H5 in many cases leads to the substantial changes of their physicochemical properties and limits application possibilities of this class of polymers especial for the medical materials. Despite the optimization of reaction conditions for each nucleophilic alkoxy substituent, the obtained poly(dia1koxyphosphaenes) exhibited some physicochemical anomalies. 相似文献
7.
N. S. Bredov E. Yu. Shporta Yanqing Liu V. V. Kireev R. S. Borisov M. V. Gorlov V. F. Posokhova V. P. Chuev 《Polymer Science Series B》2013,55(7-8):472-477
Methyl acrylate oligosilsesquioxanes based on γ-methacryloxypropyltrimethoxysilane and its mixtures with phenyltrimethoxysilane have been synthesized through acidohydrolytic polycondensation and studied via NMR spectroscopy and MALDI-TOF mass spectrometry. It is shown that the addition of the aforementioned oligosilsesquioxanes to a dental composition based on 2,2-bis[p-(3-metacryloyloxy-2-hydroxypropoxy)phenyl]propane and triethylene glycol dimethacrylate improves the mechanical characteristics of cured polymer composites. 相似文献
8.
I. S. Sirotin Yu. V. Bilichenko O. V. Suraeva A. N. Solodukhin V. V. Kireev 《Polymer Science Series B》2013,55(1-2):63-68
With the use of 31P NMR spectroscopy and gas chromatography-mass spectrometry, the partial ammonolysis of PCl5 by ammonium chloride in chlorobenzene in the presence of zinc chloride is investigated. The use of zinc chloride reduces the reaction time to 1.5 h and increases the yield of oligomeric chlorophosphazenes up to 95%. Some assumptions are made about the role of ZnCl2 in the process and about the feasibility of the mechanism of formation of higher cyclic chlorophosphazenes, the hexamer and the octamer. 相似文献
9.
M. A. Gubin A. N. Kireev A. V. Tausenev A. V. Konyashchenko P. G. Kryukov D. A. Tyurikov A. S. Shelkovikov 《Laser Physics》2007,17(11):1286-1291
The main elements needed for the realization of a compact femtosecond methane optical clock are developed and studied. A femtosecond laser system on an Er3+ fiber (λ = 1.55 μm) contains an oscillator, an amplifier, and a fiber with a relatively high nonlinearity in which the supercontinuum radiation is generated in the range 1–2 μm. In the supercontinuum spectrum, the fragments separated by an interval that is close to the methane-optical reference frequency (λ = 3.39 μm) exhibit an increase in intensity. The supercontinuum radiation is converted into the difference frequency in a nonlinear crystal to the range of the methane-reference frequency (λ = 3.3–3.5 μm), so that the frequency components of the transformed spectrum have sufficient intensities for the subsequent frequency-phase stabilization with respect to the methane reference. A system that stabilizes the pulse repetition rate of the femtosecond Er3+ laser is also employed. Thus, the repetition rate of the ultrashort pulses of the femtosecond fiber laser is locked to the methane reference. The pulse repetition rate is compared with the standard second. Thus, the scheme of an optical clock is realized. 相似文献
10.
V. A. Dyatlov T. A. Grebeneva A. A. Koledenkov B. M. Prudskov V. V. Kireev 《Polymer Science Series B》2014,56(2):154-160
The processes that occur during the processing and foaming of thermosetting composites based on a random copolymer of acrylamide and acrylic acid—softening, foaming, and curing of the copolymer—are studied with the use of methods of chemical kinetics, Fourier transform infrared spectroscopy, and thermomechanical analysis. The above processes are coordinated with respect to time and temperature; prognostic methods for calculating the dynamics of these processes and the properties of foam materials as functions of the composition of the original foam-forming composite and the foaming conditions are proposed. 相似文献