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Internal pressurization testing at room temperature was performed to evaluate the effect of flame-spraying aluminum-12silicon on the leakage behavior of fibre-reinforced composite tubes fabricated by filament winding, and covered with garnet sand. A group of specimens were completely coated with flame-sprayed metal particles and another set remained uncoated. t-tests were conducted at a significance level of α = 0.05 to analyze the effect of the coating on the leakage behavior of the specimens. Ultraviolet imaging was used to illustrate a characteristic leakage pattern of the composite tubes. Coated specimens exhibited slightly higher mean leakage and burst pressures than the uncoated specimens. The t-test results provided strong statistical evidence that the flame spraying process employed did not damage the filament wound tubes covered with garnet sand. 相似文献
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通过对泰州长江公路大桥主缆送气量和送气压力的数据分析,给出了维护阶段悬索桥主缆漏气量和送气压力之间的半经验公式,对于后期悬索桥在设计使用过程中选择正确的送气压力和送气量有一定的借鉴意义。 相似文献
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Y2O3 thin films were grown by atomic layer deposition (ALD) through a heteroleptic liquid (iPrCp)2Y(iPr-amd) precursor at 350 °C. The structural and chemical properties of both as-deposited and annealed Y2O3 films at 500 °C and 700 °C are analyzed by atomic force microscopy for variation in surface roughness, X-ray diffraction for crystalline structure, and X-ray photoelectron spectroscopy for chemical states. The as-deposited Y2O3 film shows the same crystalline orientation along the plane (222), a stoichiometric state, and minimal hydroxylate formation up to 700 °C. Being the dielectric layer in the metal-oxide-semiconductor capacitor, the as-deposited ALD-Y2O3 films with liquid (iPrCp)2Y(iPr-amd) precursor without any post-deposition annealing show the much lower leakage density than ALD-Y2O3 with solid Y(MeCp)3. 相似文献
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Optimization of leakage power is essential for nanoscale CMOS (nano-CMOS) technology based integrated circuits for numerous reasons, including improving battery life of the system in which they are used as well as enhancing reliability. Leakage optimization at an early stage of the design cycle such as the register-transfer level (RTL) or architectural level provides more degrees of freedom to design engineers and ensures that the design is optimized at higher levels before proceeding to the next and more detailed phases of the design cycle. In this paper, an RTL optimization approach is presented that targets leakage-power optimization while performing simultaneous scheduling, allocation and binding. The optimization approach uses a nature-inspired firefly algorithm so that large digital integrated circuits can be effectively handled without convergence issues. The firefly algorithm optimizes the cost of leakage delay product (LDP) under various resource constraints. As a specific example, gate-oxide leakage is optimized using a 45 nm CMOS dual-oxide based pre-characterized datapath library. Experimental results over various architectural level benchmark integrated circuits show that average leakage optimization of 90% can be obtained. For a comparative perspective, an integer linear programming (ILP) based algorithm is also presented and it is observed that the firefly algorithm is as accurate as ILP while converging much faster. To the best of the authors׳ knowledge, this is the first ever paper that applies firefly based algorithms for RTL optimization. 相似文献
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《Current Applied Physics》2015,15(3):194-200
BiFeO3 (BFO) thin films with thickness increasing from 40 to 480 nm were successfully grown on LaNiO3 (LNO) buffered Pt/Ti/SiO2/Si(100) substrate and the effects of thickness evolution on magnetic and ferroelectric properties are investigated. The LNO buffer layer promotes the growth and crystallization of BFO thin films. Highly (100) orientation is induced for all BFO films regardless of the film thickness together with the dense microstructure. All BFO films exhibited weak ferromagnetic response at room temperature and saturation magnetization is found to decrease with increase in film thickness. Well saturated ferroelectric hysteresis loops were obtained for thicker films; however, the leakage current dominated the ferroelectric properties in thinner films. The leakage current density decreased by three orders of magnitude for 335 nm film compared to 40 nm film, giving rise to enhanced ferroelectric properties for thicker films. The mechanisms for the evolution of ferromagnetic and ferroelectric characteristics are discussed. 相似文献
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