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961.
This paper studies mathematical modeling of motion of a nonlinearly viscous fluid in the case of strong solutions.  相似文献   
962.
Propagation of plane, spherical, and cylindrical waves in vapor-gas mixtures with polydisperse particles and droplets, where one of the fractions is involved in phase transformations, was studied. A disperse correlation was obtained, and disperse curves were computed. The influence of polydispersity of particles and droplets on dispersion and dissipation of small perturbations was analyzed.  相似文献   
963.
The crystal structure of gibbsite (aluminum hydroxide) has been refined by Rietveld powder diffraction analysis, and the thermal stability of the crystal structure of the mineral has been studied in detail by high-temperature X-ray diffraction. The X-ray diffraction data obtained in the temperature range from 25 to 300°C indicate that the crystal structure of gibbsite is stable up to 200–250°C. The unit-cell parameters of gibbsite increase with temperature. Above 200°C, the gibbsite to boehmite (AlO(OH)) phase transformation begins.  相似文献   
964.
针对微博平台上的垃圾用户甄别问题,本文提出了基于微博重复发送行为的垃圾用户行为建模和甄别算法。在真实微博垃圾用户数据分析的基础上,本建模方法综合考虑了微博垃圾用户的行为信息、社交网络信息和文本信息,从不同的角度对垃圾用户进行了分析和建模。在真实数据集上的实验证明了方法的有效性,并且对模型中若干参数进行了优化,同时也分析了垃圾用户行为信息、社交网络信息和文本信息对模型的影响程度。  相似文献   
965.
966.
Data are given concerning the structure and the chemical composition of carbon steel used for making cold arms, which was produced at the Zlatoust arms factory in the nineteenth and early twentieth centuries. The results of the analysis of the structure of metal demonstrates the general trend of the development of metallurgy both at the Ural plants and in the world: from the creation of the crucible methods of production of cast steel to the mass production of cast steel by the Bessemer and Martin methods.  相似文献   
967.
X-ray diffraction analysis, transmission and scanning electron microscopy, and electron microprobe analysis were used to study Bi,Pb-2223/Ag composites annealed in a low-oxygen atmosphere (7.5% O2 + 92.5% N2). The ceramics was found to be characterized by some nonuniformity in the distribution of all the components. Two structural peculiarities of the 2223 phase were found. These are the existence of atomic displacement waves, which are related to the oxygen deficiency or nitrogen substitution for oxygen, and a more intense Ag penetration into the ceramics, which results from the annealing in the O2-N2 atmosphere at a pressure of 10 atm. The unstable state of the lattice characterized by oxygen atomic displacement waves is due to the prolonged annealing in oxygen-depleted atmosphere. Usually, in the case of other favorable factors of the ceramics structure, the lattice instability positively affects the superconducting properties of the ceramics.  相似文献   
968.
The work presents a survey of the results of studies of the processes of magnetization reversal of ferromagnetic nanoparticles under the action of the field of a magnetic force microscope probe.  相似文献   
969.
Methods of X-ray diffraction (XRD) and nuclear magnetic resonance (NMR) were used to investigate the effect of milling on the properties of the hydrogen-stabilized compound ZrTi2H3.9 with the structure of the metallic sublattice of the C15 type. It has been found that the milling leads to a phase separation in the initial sample: there appears an additional phase with a structure of the TiH2 type and an average grain size of approximately 10 nm. The mobility of hydrogen in the phase of the TiH2 type is considerably lower than in the phase of the C15 type. An analysis of the results of measurements of rate the spin-lattice relaxation of 1H nuclei in wide ranges of temperatures (20–420 K) and resonance frequencies (14.6–90 MHz) allowed us to estimate the parameters of the hopping motion of hydrogen atoms in the phase of the C15 type. It has been established that an increase in the time of milling leads to a decrease in the mobility of hydrogen in this phase.  相似文献   
970.
Peculiarities of the ordered-structure formation in the equiatomic CuAu alloy, which are caused by changes in the sample dimensions and by an applied external force field, have been studied. The rate of the microstructure transformation in the ordered alloy has been found to increase with increasing thickness of the sample. It has been shown that tensile stresses applied during heat treatment can affect the growth direction of c domains and, thus, makes it possible to avoid the low-temperature cracking of the material.  相似文献   
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