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排序方式: 共有1765条查询结果,搜索用时 15 毫秒
1.
Predictions of the strength of cracked steel structural components at negative temperatures are considered. The elastoplastic stress–strain state of samples at destructive loads is studied by finite-element analysis. 相似文献
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Radiochemistry - Thermal stability of extraction systems containing N,N,N′,N?′-tetra-n-octyldiglycolamide (TODGA), di(N-ethyl-4-hexylanilide)... 相似文献
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Zorin I. V. Dubtsov Yu. N. Sokolov G. N. Lysak V. I. 《Metal Science and Heat Treatment》2019,60(11-12):757-763
Metal Science and Heat Treatment - Special features of structure and phase formation in deposited metal based on alloyed Ni3 Al nickel aluminide formed due to high-gradient crystallization under... 相似文献
6.
Markova A. I. Sokolov A. V. Galitsyn V. P. Khizhnyak S. D. Ruehl E. Pakhomov P. M. 《Fibre Chemistry》2022,53(5):296-299
Fibre Chemistry - An optical spectroscopic method for analyzing the quality of the solvent used for gel-spinning of ultra-high-molecular-weight polyethylene was proposed using Vaseline oil (VO) as... 相似文献
7.
N. A. Kozyrev N. V. Kibko A. A. Umanskii D. A. Titov P. D. Sokolov 《Welding International》2018,32(11):724-728
ABSTRACTExperiments were carried out to investigate the effect of adding carbon–fluorine compounds (the waste from metallurgical production) and nickel powder to the composition of flux-cored wires of the C–Si–Mn–Cr–W–V and C–Si–Mn–Cr–V–Mo alloying systems. The results show that the addition of these compounds to the composition of the charge for producing the wires of the 35V9Kh3SF and 25Kh5FMS types improves a large number of the characteristics of the deposited layer: reduces the extent of contamination with non-metallic inclusions, increases the hardness of the deposited layer, refines austenite grains and results in the formation of fine-dispersion carbides which in practice may improve the thermal resistance of rolling rolls, and also prevents the formation of a ferrite network which may have a beneficial effect on cracking resistance. The experimental results can be used to develop new compositions of flux-cored wires for hardfacing rolling rolls protected by Russian Federation patents. The hardfacing technologies of the rolls using these flux-cored wires with the C–Si–Mn–Cr–W and C–Si–Mn–Cr–V–Mo alloying systems are now produced by the ElSib company. 相似文献
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S. Aranovskiy R. Ortega J. G. Romero D. Sokolov 《International journal of control》2019,92(7):1620-1633
It is shown in the paper that the problem of speed observation for mechanical systems that are partially linearisable via coordinate changes admits a very simple and robust (exponentially stable) solution with a Luenberger-like observer. This result should be contrasted with the very complicated observers based on immersion and invariance reported in the literature. A second contribution of the paper is to compare, via realistic simulations and highly detailed experiments, the performance of the proposed observer with well-known high-gain and sliding mode observers. In particular, to show that – due to their high sensitivity to noise, that is unavoidable in mechanical systems applications – the performance of the two latter designs is well below par. 相似文献
10.
Chao Wen Alexander G. Banshchikov Yury Y. Illarionov Werner Frammelsberger Theresia Knobloch Fei Hui Nikolai S. Sokolov Tibor Grasser Mario Lanza 《Advanced materials (Deerfield Beach, Fla.)》2020,32(34):2002525
Mechanically exfoliated 2D hexagonal boron nitride (h-BN) is currently the preferred dielectric material to interact with graphene and 2D transition metal dichalcogenides in nanoelectronic devices, as they form a clean van der Waals interface. However, h-BN has a low dielectric constant (≈3.9), which in ultrascaled devices results in high leakage current and premature dielectric breakdown. Furthermore, the synthesis of h-BN using scalable methods, such as chemical vapor deposition, requires very high temperatures (>900 °C) , and the resulting h-BN stacks contain abundant few-atoms-wide amorphous regions that decrease its homogeneity and dielectric strength. Here it is shown that ultrathin calcium fluoride (CaF2) ionic crystals could be an excellent solution to mitigate these problems. By applying >3000 ramped voltage stresses and several current maps at different locations of the samples via conductive atomic force microscopy, it is statistically demonstrated that ultrathin CaF2 shows much better dielectric performance (i.e., homogeneity, leakage current, and dielectric strength) than SiO2, TiO2, and h-BN. The main reason behind this behavior is that the cubic crystalline structure of CaF2 is continuous and free of defects over large regions, which prevents the formation of electrically weak spots. 相似文献