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Zhishen Wu Yixin Shao Kentaro Iwashita Koji Sakamoto 《Canadian Metallurgical Quarterly》2007,11(3):299-307
Reinforced concrete (RC) beams subject to service loads of 40 or 60% of steel yielding were strengthened using hybrid continuous carbon fiber sheets. The hybrid systems were made of high-strength and high-modulus carbon sheets, and compared with systems using only high-strength carbon. It was found that the use of high-modulus carbon sheets in hybrid systems could increase the yielding load, the flexural stiffness, the postyielding ductility, and reduce the crack opening in concrete. The slope changes on load-deflection curves at steel yielding are not noticeable in hybrid systems. The tensile strains developed in hybrid sheets after the fracture of high-modulus carbon are higher in magnitude and distributed in a larger area, leading to an ultimate carbon fracture with concrete crushing. These unique features are attributed to the high stiffness and low ultimate tensile strain of the high-modulus carbon fibers which stiffen the structures, avoid or delay the fiber-reinforced polymer debonding, and facilitate the deformability during their subsequent breakdown. 相似文献
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本文建立了河口三维非线性斜压水流盐度数学模型。该模型通过。坐标变换,使整个水域垂直方向可采用相同的分层。基于过程分裂法,将三维流动分成表面重力波(外模式)和内重力波(肉模式)。外模式采用改进型双步全隐有限差分DSI法进行计算,内模式利用欧拉-拉格朗日公式,改进三维垂直方向隐式格式,减小了数值耗数,提高了计算精度及稳定性。该模型应用于长江口三维盐水入侵计算,结果表明水流盐度分布与实测一致。 相似文献
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Yixin HUA F.R.Sale 《材料科学技术学报》1996,12(5):389-394
The reduction rate and microstructural changes of imperial smelting furnace (ISF) sinter have been investigated by means of thermogravimetric analysis, X-ray difFraction (XRD), scanning electron microscope (SEM ), energy dispersive analysis of X-ray (EDAX) and optical microscope.It is demonstrated that the overall reaction rate of the reduction is influenced by temperature and hydrogen partial pressure in H2 /N2 gas mixtures. There are two distinct zones observed in the partially reduced sinter. The reduction of zincite proceeds predominantly in a narrow range between the two zones, while the reduction of tead oxide and silicate takes place throughout the sinter. The differences between zincite and lead oxide or silicate in reducibility are analysed by thermodynamlcs. The phase transformations and microstructural changes occurring during the reduction process are discussed 相似文献
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In this paper, the detectivity is calculated and analyzed with the front-or backside illuminated case for both N-GaSb/p2-Ga0.8In0.2As0.19Sb0.81/p1-Ga0.9In0.1As0.09Sb0.91 and N1-GaSb/n2-Ga0.9In0.1As0.09Sb0.91/p-Ga0.8In0.2As0.19Sb0.81 infrared photovoltaic detectors, respectively. The analysis results show that the main absorption appears in the p-type Ga0.8In0.2As0.19Sb0.81 material with either front- or backside illuminated case for above two structures. In each structure, the carrier concentration obviously affects the detectivity. The carrier concentration in the wide-bandgap material for the isotype heterojunction should be reduced as low as possible to reduce the tunneling rate at the isotype heterointerface. Moreover, the change of the detectivity with the p-side surface recombination velocity for the N1-n2-p structure is more sensitive than that with the p1-side surface recombination velocity for the N-p2-p1 structure. In the N-p2-p1 structure with the incident light from the p1-side surface, two-color detection is achieved. 相似文献
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我国煤炭生产的环境问题及其对策研究 总被引:4,自引:1,他引:3
论文分析了我国煤炭生产中所存在的环境问题 ,并提出采取应用全面绿色管理、贯彻实施ISO14 0 0 0系列标准及推广应用清洁生产等对应措施和方法。其中全面绿色管理是作者首次提出的全新概念。 相似文献
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The flexural and shear rigidity of pultruded composite sheet pile panels consisting of E-glass fiber-reinforced polyester are studied in this paper. The analysis consists of an experimental investigation and an analytical modeling to determine the resistance of the sheet pile panels to the deflections for design of composite sheet pile walls. Timoshenko’s beam theory was used to experimentally determine the flexural rigidity (EI) and shear rigidity (kAG) of the panel. Three- and four-point bending tests were performed on six different span lengths and the results were self-compared from the two independent tests. Analytical expressions for the flexural and shear rigidities were derived to allow the prediction based on the layered structure of pultruded shapes. The values computed from the analytical expressions were examined with the experimental results. 相似文献
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设计一电路,将彩色图象信息编码到黑白CRT的亮度之中,并将其写入液晶光阀,用白光读出,当编码合适时,读出的象颜色可与原图像一致。本文讨论了这一技术原理并进行了单液晶光阀彩色大屏幕投影的实验验证。 相似文献
10.
穷举法是程序设计中经常用到的一种算法,用来解决一些用常规的数学方法无法解决的问题.文章通过两个典型的例子对穷举法的思路和有关注意事项进行了分析,供编程学习者参考. 相似文献