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991.
Andrey Polyakov AleksAndr Zhabin Eugene Averin Aleksey Polyakov 《岩石力学与岩土工程学报(英文版)》2019,11(4):867-873
One of the promising methods for rock cutting technology is the use of high-speed water jets.In order to improve the cutting capacity of water jets without increasing the hydraulic power of equipment,pulsed water jets are basically used to increase the rock cutting efficiency.However,there are no mature recommendations for selection of rational parameters,and the relationship between indicators of rock cutting efficiency and parameters of pulsed water jet is still not established.In this context,we aimed at developing a generalized equation for calculating rock cutting efficiency,in which all the major parameters in consideration of rock cutting process are included.Then,a calibration of the rational parameters of rock cutting by pulsed water jets was conducted.The results are likely helpful for increasing productivity and reducing energy consumption. 相似文献
992.
Victor A. Krivchenko Daniil M. Itkis Stanislav A. Evlashin Dmitry A. Semenenko Eugene A. Goodilin Alexander T. Rakhimov Anton S. Stepanov Nikolay V. Suetin Andrey A. Pilevsky Pavel V. Voronin 《Carbon》2012,50(3):1438-1442
Carbon nanowalls (CNWs) are suggested as a promising nanostructured substrate for 3D anodes of lithium-ion batteries. Silicon sputtering onto CNWs results in improved electrochemical performance due to either a large surface area of free-standing CNWs or easy adhesion of deposited silicon clusters via the SiC interface layer formation. The 3D silicon-decorated nanowall framework (SDNF) could give the possibility to minimize the lithium diffusion length and make charge collection more effective yielding better cycling performance at high rates exceeding 2000 mA h per 1 g of silicon in the range of 0.05–2.00 V at 1.5 C rate. 相似文献
993.
This note discusses the pioneering role and main contributions of V.S. Tanaev in the field of cyclic robotic flowshop scheduling. Open questions (either explicitly or implicitly) posed in his papers and kept unsolved up to date are exposed. 相似文献
994.
Andrei V. Kovalevsky Eugene N. Naumovich Aleksey A. Yaremchenko Jorge R. Frade 《Journal of the European Ceramic Society》2012,32(12):3255-3263
Iron-based oxides are considered as promising consumable anode materials for high temperature pyroelectrolysis. Phase relationships, redox stability and electrical conductivity of Fe3?xAlxO4 spinels were studied at 300–1773 K and p(O2) from 10?5 to 0.21 atm. Thermogravimetry/XRD analysis revealed metastability of the sintered ceramics at 300–1300 K. Low tolerance against oxidation leads to dimensional changes of ceramics upon thermal cycling. Activation energies of the total conductivity corresponded to the range of 16–26 kJ/mol at 1450–1773 K in Ar atmosphere. At 1573–1773 K and p(O2) ranging from 10?5 to 0.03 atm, the total conductivity of Fe3?xAlxO4 is nearly independent of the oxygen partial pressure. The conductivity values of Fe3?xAlxO4 (0.1 ≤ x ≤ 0.4) at 1773 K and p(O2) ~10?5 to 10?4 atm were found to be only 1.1–1.5 times lower than for Fe3O4, showing high potential of moderate aluminium additions as a strategy for improvement of refractoriness for magnetite without significant deterioration of electronic transport. 相似文献
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The management of a military supply chain (SC) involves the integration of production, packaging, warehousing, repair, maintenance and transportation of army supplies. In this paper, we focus on the integrated demand-responsive scheduling of maintenance and transportation operations within the SC. We consider a modular representation of a SC, in which the maintenance and transportation operations constitute the corresponding modules. An efficient integration of these operations is carried out by an additional controlling (commanding) module. We describe and analyse the optimisation problems arising in each module. The main contribution of the paper is that the analysis and optimisation of the controlling module permit to enhance the performance of the entire SC. Computational experiments prove the validity and effectiveness of the suggested models. 相似文献
999.
Phase Constitution and Dynamic Properties of Spark Plasma‐Sintered Alumina–Titanium Composites 下载免费PDF全文
Shmuel Hayun Shai Meir Sergey Kalabukhov Nahum Frage Eugene Zaretsky 《Journal of the American Ceramic Society》2016,99(2):573-580
Al2O3/Ti composites of various metal to ceramic ratios were fabricated by the spark plasma sintering (SPS) technique. The effects of titanium concentration in the initial mixture on phase composition, and on the static and dynamic (planar impact testing) mechanical properties of the SPS‐processed composites were investigated. It was observed that the significant alumina dissolution in titanium takes place during SPS treatment. The composites fabricated from starting alumina/titanium powder mixtures with a mass fraction of titanium less than 0.8 consisted of two phases, alumina and a solid solution of oxygen and aluminum in titanium. For starting mixtures with higher titanium content, the presence of a Ti3Al intermetallic phase with a relatively low fraction of dissolved oxygen was detected. Changes in phase composition could explain the effect of titanium content in the starting mixture on physical and mechanical properties of the composites. Mechanisms governing the dynamic response of the composites under loading of different intensities are discussed. 相似文献
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