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981.
V. Ocelík V. Z. Bengus E. B. Korolkova K. Csach J. Miškuf P. Duhaj 《Journal of Materials Science》1991,26(24):6699-6705
The fracture stress and the critical stress intensity factor of the Fe40Ni40B20 amorphous metallic ribbons 20 μm thick were measured in the temperature range 4.2–300 K and at deformation rates from 3.3×10−6 to 1.25×10−3 m−1 with the aim to obtain more information on the condition for the onset and development of the inhomogeneous plastic deformation
and fracture. 相似文献
982.
A possible method for the simulation of nonideal op-amps with a finite gain and bandwidth by means of an equivalent SC circuit, containing ideal components, is presented. The approach is extended by the case of an op-amp with non-switched input SC building blocks. 相似文献
983.
984.
985.
S. A. Bulgakov V. B. Ryabov V. I. Shnyrkov D. M. Vavriv 《Journal of Low Temperature Physics》1991,83(5-6):241-255
The oscillation dynamics of a nonhysteretic, one-contact superconducting quantum interferometer under low-frequency modulation of an external magnetic flux has been studied. It is shown that even in the case of adiabatic, equilibrium, and nonhysteretic operation modes of a superconducting ring enclosed by a weak link, there can appear chaotic oscillations. The conditions of chaos arising have been considered analytically and numerically; mechanisms and destruction scenarios of periodic oscillations have been studied. The stochastic instability could impose limitations on the increase in sensitivity of nonhysteretic SQUIDs, which was earlier predicted to be high enough. 相似文献
986.
The removal of Cu(II) by adsorption on fly ash has been found to be concentration, pH and temperature dependent. The kinetics of adsorption indicates the process to be diffusion controlled. The Langmuir constants have been calculated at different temperatures, and the adsorption has been found to be endothermic (ΔH = 15.652 kcal mol?1). The maximum removal is observed at pH 8.0, and variation in adsorption with pH has been explained on the basis of surface ionisation and complexation. 相似文献
987.
The oxygen solubility in Fe-Si melts in equilibrium with SiO2 at 1873 K has been determined in a concentration range of 0.1–70 wt % Si. Model alloys are melted in quartz crucibles in an argon atmosphere. The oxygen content in analytical samples is determined by the inert-gas reducing-fusion method after careful sample preparation. The results obtained have been processed using a thermodynamic model that can calculate the oxygen activity and solubility in Fe-Si melts up to 100 wt % Si. The effects of the heating rate and the silicon content on the carbon concentration in carbonyl iron and Fe-Si alloys are studied using the inert-gas reducing-fusion method in the temperature range 1673–2373 K. Oriented electrical steels are investigated using fractional gas analysis. The main forms of oxygen in these steels are found to be silicates, Al2O3, and MgAl2O4. 相似文献
988.
目前,分布式电源架构被广泛用于通信和计算设备中,该电源架构经常采用板载电源(BMP)模块,在尽可能靠近负载点的地方进行电源变换. 相似文献
989.
O. G. Devoino M. A. Kardapolova S. Laber E. A. Feldstein O. V. Diyachenko 《Journal of Engineering Physics and Thermophysics》2004,77(2):372-376
The wear resistance of Ni–Cr–B–Si–C coatings after laser treatment with a doping covering under dry friction conditions has been investigated. The microstructure of coatings after fusion by a gas burner and a laser beam and the roughness and waviness parameters of the friction surfaces before and after wear have been investigated. 相似文献
990.
Stress State of Bent Buried Pipelines 总被引:1,自引:0,他引:1
The authors consider edge effects in buried pipelines that occur in the region of joining of a straight buried pipe and a bent insert (factory bend, elbow, or an elastically bent segment). The action of those effects results in the appearance of additional bending moments, which are proportional to the difference between the axial force in an infinite straight pipeline and that in a closed-end pipe, and depend on the geometrical parameters of the pipeline and physical-mechanical characteristics of the soil. Specific examples of analysis of elastic interaction of a pipeline with the soil for pipe bends with various radii of the bend arc are offered. It is shown that additional bending stresses may exceed appreciably the stresses from the axial force, and therefore, they should be taken into account when designing and building pipelines. The solution for an elastically bent segment has been obtained and analyzed. 相似文献