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21.
The qualitative analysis of a class of dynamic population models that are in commensal relationships and compete for one substrate
is carried out. The stability of all the stationary conditions is analyzed. All the singularities are found analytically and
constraints are obtained for species growth characteristics and initial flows of the substrate and product. The qualitative
changes in the dynamics due to variations of several system parameters are analyzed and bifurcation diagrams are constructed
for all the singular points. 相似文献
22.
D. A. Starostenko V. V. Sherstnev P. A. Alekseev I. A. Andreev N. D. Il’inskaya G. G. Konovalov O. Yu. Serebrennikova Yu. P. Yakovlev 《Technical Physics Letters》2011,37(10):935-938
Photodiodes with a photosensitive area of 0.45 × 0.45 mm2 operating at room temperature in a wavelength range bounded by 4.9 μm have been created on the basis of InAs/InAs0.94Sb0.06/InAsSbP/InAs0.88Sb0.12/InAsSbP/InAs heterostructures grown by liquid phase epitaxy. A distinguishing feature of the proposed photodiodes is extended
(λmax = 1.5–4.8 μm) spectral sensitivity range, in which the photodiode is characterized by a monochromatic responsivity of 0.5–0.8
A/W and a dark current density of 1.0–1.5 A/cm2 at a reverse bias of 0.2 V. The differential resistance at zero bias reaches up to 20–100 Ω. The detection ability of photodiodes
in the region of maximum sensitivity reaches (1–2) × 108 cm Hz1/2 W−1. 相似文献
23.
24.
Popov A.A. Sherstnev V.V. Baranov A.N. Alibert C. Yakovlev Y.P. 《Electronics letters》1998,34(14):1398-1399
A continuous-wave regime, lasing near 2.2 μm, has been achieved for single longitudinal mode GaInAsSb double heterostructure lasers mounted on a Peltier cooler. In the pulsed regime the lasers exhibited a characteristic temperature of the threshold current as high as 132 K at heatsink temperatures up to 60°C 相似文献
25.
V. L. Yakovlev G. D. Karmaev V. A. Bersenev A. V. Glebov A. V. Semenkin I. G. Sumina 《Journal of Mining Science》2016,52(1):102-109
The article reviews in brief application of cyclical-and-continuous method in the conveyor-andtruck haulage in open pit mines. Consumption of materials and power is evaluated as a function of mined rock haulage volumes and depth of crush-and-reload station position in an open pit mine. The change in capital and operational cost to transport ore and hard overburden is studied at varied distances from a crushand- reload station in open pit to a surface receiving station. Efficiency of the conveyor-and-truck haulage using cyclical-and-continuous method is evaluated. In terms of deep and large mineral deposits, the authors substantiate positions for crush-and-reload stations in large open pit mines. 相似文献
26.
27.
E. A. Lysenkov V. V. Klepko Yu. V. Yakovlev 《Surface Engineering and Applied Electrochemistry》2016,52(2):186-192
The electrical properties of the polyether/carbon nanotube (CNT) systems doped with LiClO4 inorganic salt are studied via impedance spectroscopy. The percolation thresholds are evaluated in the context of the standard percolation theory for the nanofilled systems based on polyethylene glycol and polypropylene glycol, being 0.45 and 0.5%, respectively. Two percolation thresholds are observed for the polyether–CNT–LiClO4 systems. A modified percolation model with consideration of two percolation transitions is proposed. 相似文献
28.
A. A. Petukhov B. E. Zhurtanov K. V. Kalinina N. D. Stoyanov H. M. Salikhov M. P. Mikhailova Yu. P. Yakovlev 《Semiconductors》2013,47(9):1258-1263
The electroluminescent properties of an n-GaSb/n-InGaAsSb/p-AlGaAsSb heterostructure with a high potential barrier in the conduction band (large conduction-band offset) at the n-GaSb/n-InGaAsSb type-II heterointerface (ΔE c = 0.79 eV) are studied. Two bands with peaks at 0.28 and 0.64 eV at 300 K, associated with radiative recombination in n-InGaAsSb and n-GaSb, respectively, are observed in the electroluminescence (EL) spectrum. In the entire temperature range under study, T = 290–480 K, additional electron-hole pairs are formed in the n-InGaAsSb active region by impact ionization with hot electrons heated as a result of the conduction-band offset. These pairs contribute to radiative recombination, which leads to a nonlinear increase in the EL intensity and output optical power with increasing pump current. A superlinear increase in the emission power of the long-wavelength band is observed upon heating in the temperature range T = 290–345 K, and a linear increase is observed at T > 345 K. This work for the first time reports an increase in the emission power of a light-emitting diode structure with increasing temperature. It is shown that this rise is caused by a decrease in the threshold energy of the impact ionization due to narrowing of the band gap of the active region. 相似文献
29.
The influence of temperature on the phase composition of a cast aluminum alloy which contains 0.55% Zr, 0.23% Fe, and 0.06% Si is investigated in order to substantiate the optimal annealing modes using the Thermo-Calc program. The phase composition is determined and the equilibrium compositions of the aluminum solid solution in the Al-0.55% Zr-0.23% Fe-0.06% Si at t = 200–650°C is calculated. It is shown that, when using multistage annealing, the maximal hardness and conductivity are attained at t = 400–450°C. 相似文献
30.
M. G. Yakovlev 《Journal of Machinery Manufacture and Reliability》2014,43(4):283-286
The paper deals with a comparison of results of measuring residual stresses and with the study of their effect on the fatigue strength of parts of gas-turbine engines after finish treatments by grinding, polishing, and surface plastic deformation. 相似文献