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91.
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Environmental process and compositions of the interior and exterior spaces period, outside the species is a continuation of mixing. Ability to Cities Climate Progress Street Development (CCPSD) under development and urban ecosystem is of great interest. Like the collaborative process, the chemical composition and natural finish edge has appeared on the stage. Urban development is inseparable from the appearance of human experience, a more complete overall climate. Gradually different base and current methods of life living material, natural integration plan needs a metropolitan area, then specific social nature and philosophy of environmental protection of the city, and more thoughts. In this article, method will focus on metropolitan areas the natural clear plan to complete the examination. Set best-effort edge within the metropolitan area to explicitly check liner Field Programmable Gate Array (FPGA). The purpose and work planning and layout of the system need to be considered. 相似文献
93.
《Journal of the European Ceramic Society》2020,40(3):706-711
The demand for lead-free dielectric capacitors with rapid charge-discharge ability and high energy storage density is increasing owing to the rapid development of electronic equipment. Lead-free Sr1-x(Bi0.5Li0.5)xTi0.99Mn0.01O3 (x = 0.02, 0.025, 0.03, 0.035) thin films grown on Pt/Ti/SiO2/Si substrates were prepared by sol-gel method. A huge enhancement in polarization was found in Bi3+-Li+ co-doped SrTiO3 thin films. The large lattice distortion and local broken-symmetry due to formation of Bi3+-Li+ ionic pairs are responsible for ferroelectricity and high polarization. The maximum polarization (42.1 μC/cm2) and largest energy storage density of 47.7 J/cm3 at 3307 kV/cm were both achieved in Sr0.975(Bi0.5Li0.5)0.025Ti0.99Mn0.01O3 thin film. Moreover, an excellent temperature-dependent stability was also obtained in Sr0.975(Bi0.5Li0.5)0.025Ti0.99Mn0.01O3 thin film from 30 to 110 °C. 相似文献
94.
In recent years, research in education and study abroad has focused on collaborative research between education and learning, for example, using “diversified education” and “flexible education” in the teaching process. Simultaneously, colleges in numerous nations likewise that undergrad instruction must address self-association and variation models in the training and learning measure. These advanced instructive thoughts and college strategies offer viable hypothetical help for this study. However, the traditional educational model of “diversity” and “cognitive flexibility” pays attention to the difference in student learning knowledge. Personal Career Goals: In other words, this model is designed from educational content instructions, ignoring key factors. It must be a difference in the actual meaning of the development of the “diversity” student personality. Therefore, despite the various social systems, the importance of reforms in foreign universities and education has improved, reflecting previous experimental educational effectiveness assessments, reflecting the development of traditional educational theories based on the FPGA and Convolutional Neural Network (CNN). Teach and summarize your experience. In Reality, it easy to find a universal educational model. Because the actual educational model comes from achieving educational goals, consensus can be obtained from numerous educational theories and practical studies. 相似文献
95.
《International Journal of Hydrogen Energy》2019,44(7):3649-3657
A facile method is proposed to prepare cobalt supported on nitrogen-doped porous carbon material with high graphitization degree by using chitosan as carbon source, urea as soft template and poloxamer as dispersant. The prepared cobalt-carbon material (Co@NPC) shows that uniformly distributed cobalt nanoparticles are encapsulated in nitrogen-doped porous carbon bundle with large specific surface area. When Co@NPC is applied as electrode in hydrogen evolution reaction, it exhibits superior electrocatalytic performance with low overpotential (η10 = 259 mV), small Tafel slope (99 mV dec−1) and high stability with 83% of its original current density remained after 6 h electrochemical test in 1 M potassium hydroxide electrolyte. 相似文献
96.
《International Journal of Hydrogen Energy》2019,44(40):22519-22526
In this study, the effects of pipe bundle geometries on the detonation velocity behaviors are examined systematically in a circular tube with 6 m long and an inner diameter of 90 mm. The tube bundle structures are created by inserting several small pipes (20 mm outer diameter, 2 mm wall thickness) into the tube. Three different bundle structures can be obtained by varying the number of small pipes n of 3, 4 and 5. The ionization probes and pressure transducers (PCB102B06) are used to determine the average velocity while the smoked foil technique is employed to register the detonation cellular structures. The experimental results indicate that detonation can propagate at about the theoretical CJ velocity with a small deficit when the initial pressure (P0) is greater than the critical value (Pc). The average velocity gradually decreases and deviates from the CJ value as the approaches of critical condition by gradually decreasing the initial pressure. The failure of detonation can be observed below the critical pressure. In the smooth tube, three different propagation mechanisms can be observed, i.e., super-critical condition, critical condition and sub-critical condition. After the bundle structures are introduced into the tube, a sudden velocity drop is seen at the critical pressure. Moreover, the detonation re-initiation phenomenon occurs with the velocity from the flame back to over-driven state quickly. Of note is that nearly no difference is seen between n = 3 and 4. However, in the case of n = 5, the detonation velocity experiences a more violent fluctuation with a high frequency, and the critical pressure is also increased to 28 kPa sharply. Finally, the critical condition analysis of detonation successful transmission is performed. The critical condition can be quantified as DH/λ > 1. However, the critical values of DH/λ are not uniform among various bundle geometries, but in a small range, i.e., from 1.52 to 1.97. 相似文献
97.
98.
Liu Dong Liu Wenting Fu Qiang Zhang Yongjia Li Tianxiao Imran Khan M. Abrar Faiz M. 《Water Resources Management》2017,31(11):3607-3625
Water Resources Management - Water shortages are common in society, and the effective allocation of limited water resources to each competitive sector has become one of the urgent concerns for... 相似文献
99.
气体钻井过程中,当钻遇水层时,地层出水容易造成岩屑聚并,影响井眼净化效果,严重时会导致施工无法正常进行,因此地层出水是限制气体钻井应用范围的最大障碍之一。当地层微量出水时,可采用增大气体注入量的方法继续钻进,而计算增加多少气体注入量是关键。前人只研究了地层大量出水条件下,地层出水量与注气量的关系。为此,在前人研究的基础上,对气体钻井过程中地层微量出水时的携岩基本规律和有关理论进行了研究,并对气体钻井过程中最小气体注入量模型进行了分析和修正,从而推导出了确定地层微量出水时气体钻井所需最小注气量的计算公式,以方便现场计算地层微量出水时所需的最小注气量,指导气体钻井安全顺利进行,以达到提高钻井速度、节约钻井成本的目的。 相似文献
100.