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71.
72.
Bolshakov A. D. Dvoretckaia L. N. Fedorov V. V. Sapunov G. A. Mozharov A. M. Shugurov K. Yu. Shkoldin V. A. Mukhin M. S. Cirlin G. E. Mukhin I. S. 《Semiconductors》2018,52(16):2088-2091
Semiconductors - In this paper we demonstrate the results on selective area growth of GaP nanowires via self-catalyzed growth method using molecular beam epitaxy (MBE) technique on patterned... 相似文献
73.
S. N. Grigor’ev S. V. Fedorov M. D. Pavlov A. A. Okun’kova Ye Min So 《Journal of Friction and Wear》2013,34(1):14-18
The surface of the WC/Co carbide tool was modified by an electron beam with the magnetron sputtering of Nb + Hf + Ti alloy to obtain a gradient interlayer before hardfacing with (Ti + Al)N. The results of investigations of the composite using a scanning electron microscope equipped with a device for X-ray energy dispersion spectroscopy are given. The results of the comparative mechanical tests show reduced wear rate. 相似文献
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A recently proposed new large class of one-dimensional binary sequences, called extended pseudorandom sequences, is investigated.
It is shown that they enable one, in practice, to optimize a radiation-physical experiment and to solve problems of emission
planar tomography more effectively using integral-code measurement systems. 相似文献
76.
B. D. Rogozkin N. M. Stepennova Yu. E. Fedorov M. G. Shishkov F. N. Kryukov S. V. Kuzmin O. N. Nikitin A. V. Belyaeva L. M. Zabudko 《Atomic Energy》2011,110(6):412-429
The results of post-reactor studies of U0.55Pu0.45N and U0.4Pu0.6N mixed mononitride fuel elements (density 85% of the theoretical value) and a helium sublayer are presented. The fuel elements
are irradiated in a BOR-60 reactor to burnup 9.4 and 12.1% h.a., respectively, with power density 430 and 540 W/cm. All fuel
elements remained hermetic; the ChS-68 steel cladding (20% cold deformation) retained excess plasticity. The maximum zone
of interaction between the cladding and the fuel and fission products did not exceed 15 μm. The swelling rate of U0.4Pu0.6N and U0.55Pu0.45N fuel was 1.1 and 0.68%/% burnup, respectively. The gas release did not exceed 19.3 and 19%. The steel damage dose was 43
dpa. The character of the porosity distribution in the fuel affects the swelling and gas release. 相似文献
77.
Mykhaylo Fedorov 《International Journal of Thermal Sciences》2010,49(7):1277-1287
Exact analytical solutions of one-dimensional gas dynamics are intensively applied in engineering practice as a tool in modelling and simulating the piping systems that utilize a compressible medium as their working fluids. Well-known exact analytical solutions for simple types of flows, i.e. for flow processes in which only a single effect is taken into account (e.g. such limiting cases of flows as isentropic, adiabatic or isothermal), are classics of modern one-dimensional gas dynamics theory formed in the first half of last century. At present, gas dynamics does not possess an exact analytical solution for more than a single factor bringing about changes in fluid properties. In this paper the possibility of obtaining general and particular solutions of a non-linear ordinary differential equation (ODE) system describing one-dimensional steady-state flow of compressible ideal gas in constant area ducts with a constant heat flux and friction factor is discussed. It shows that ODE system variables can be separated, and integrals can be taken in terms of elementary functions. Since an analytical solution is the most important result of the paper, its detailed derivation is presented. The mathematical properties of the solution are analyzed in order to calculate this type of compressible flow. For the purpose of this analysis, the functions of the solution and duct performance characteristics of the flow model are demonstrated for various flows and heat flux values, as well as distributions of flow parameters along the duct for both subsonic and supersonic flows. The thermodynamic constraints of the solution are also studied. The analytical solution formulas obtained in this paper may serve as a definition of heat flux and friction factor in ducts from a viewpoint of one-dimensional gas dynamics. 相似文献
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