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王福顺 《探矿工程(岩土钻掘工程)》2007,34(Z1):236-238
五矿帷幕注浆截流工程的实施,切断了富水区范围内的补给水源和通道,将地表水拦截在井田之外,减少了矿井涌水量,取得了较好的经济与社会效益.分析了矿区水文地质条件;介绍了帷幕注浆施工工艺;并对帷幕注浆截水效果进行了评价. 相似文献
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Underwater radiated noise is one of the most important performances related to the stealth of a naval vessel. However, the evaluation frequently cannot be performed due to the problem of the test expense. The specification of the hull vibration is an effective method used to specify the underwater radiated noise indirectly. Therefore, in order to specify hull vibration, the sound radiation efficiency should be correctly determined. In this paper, the sound radiation efficiency which was modified with experimentally derived sound radiation efficiency as well as Maidanik’s and Uchida’s sound radiation efficiency is suggested and verified through experiments. Based on the determined sound radiation efficiency in this research, the specification of the hull vibration to satisfy with the limit of the underwater radiated noise is suggested for a ship. 相似文献
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Jae Sung YOON Tae-Jin JE Doo-Sun CHOI Sung Hwan CHANG Kyung-Hyun WHANG 《中国有色金属学会会刊》2011,(Z1):100-103
A novel fabrication process for micro patterns with curvature was introduced. The curved structures were made by compensating rectangular micro structures with liquid photoresist layer. Because of the surface tension of the liquid in micro scale, various shapes of meniscus can be made on the micro channels. The micro channels were made on the silicon substrate in advance, and then the liquid layer was coated on the micro channels. From the nature of liquid behavior, the curved patterns with smooth surface are obtained, which cannot be made easily with the conventional mechanical machining, as well as with the microfabrication processes, such as wet and dry etching. With this principle, it is expected that the smooth and curved surfaces can be made by simple processes and the results can be applied widely, such as optical patterns. 相似文献
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Since the engine and reduction gears in naval vessels are usually supported by a separate mounting system, misalignment between the reduction gears’ input shaft and the engine’s power transfer shaft occurs as a result of the ship’s motion. In this study, this misalignment is experimentally estimated using CAE by identifying the force and moment of the engine at its center of gravity. The force and moment are calculated using 3 acceleration signals on the engine assuming that the motions of the engine and reduction gear system are rigid-body motion. Using CAE and the estimated force of the engine, the vibration displacement of the engine’s power transfer shaft can be estimated and a design to reduce this vibration displacement can be suggested. 相似文献
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TiAl基合金的高温塑性变形行为 总被引:1,自引:0,他引:1
采用Gleeble-1500热模拟机在变形温度为1 000~1 150 ℃、应变速率为10~(-3)~10~0 s~(-1)的变形条件下,研究Ti-47Al-2Cr-0.2Mo(摩尔分数,%)合金的热变形行为.利用光学显微镜和扫描电子显微镜分析合金在不同变形条件下的组织演化规律.结果表明:流变应力随着应变速率提高和变形温度降低而增大;在变形过程中,流变应力随着变形量增大而增大,当流变应力达到峰值后趋于平稳,表明合金在变形过程中发生了动态再结晶;热变形过程的流变应力可采用双曲正弦本构关系来描述,平均激活能为337.75 kJ/mol;从合金的组织演化过程中可以看出,合金中不均匀的原始组织得到明显均匀化,变形后的组织是由α_2/γ层片晶团和γ晶粒组成的双态组织,在α_2/γ层片晶团和γ晶粒的晶界交界处发现分布均匀的B_2相,并且随着变形温度升高B_2相数量逐渐减少. 相似文献
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化学气相沉积TaC涂层的微观形貌及晶粒择优生长 总被引:1,自引:1,他引:0
利用TaCl5-Ar-C3H6体系,采用X射线衍射技术和扫描电镜研究不同温度下化学气相沉积TaC涂层微观形貌及晶粒择优生长.结果表明:在800~1 200℃时,随沉积温度升高,TaC颗粒从圆球形逐渐转变为多角形以及金字塔形多面体,而其晶体择优取向依次从无明显择优取向向<220>和<200>转变;利用生长参数α和VAN DERDRIFT,MEAKIN的纳米级晶粒选择生长模型可较好地解释不同形貌的生长机制.当α=3时,薄膜会优先生长成<200>择优取向的金字塔晶粒;当α=1.5时,则容易生长成(220>取向的多角形晶粒. 相似文献
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Kamran Ali Chang Young Kim Kyung-Hyun Choi 《Journal of Materials Science: Materials in Electronics》2014,25(4):1922-1932
This paper reports on the fabrication of good quality Al2O3 thin films on flexible substrates including polyethylene naphthalate (PEN), polyethylene terephthalate (PET) and Polyamide at different temperatures down to 50 °C under very short water purging steps of 10 s. Al2O3 films with appreciable growth rates having good morphological, chemical, electrical and optical characteristics have been produced. Growth rates of 1.16, 1.14 and 1.15 Å/cycle have been observed at 50 °C for PET, PEN and polyamide substrates respectively. The surface morphology has been improved with the increase in deposition temperature. Low average arithmetic roughness of 0.88 and 0.78 nm have been recorded for the Al2O3 films deposited at 150 °C on PEN and polyamide respectively. The XPS analysis confirmed the fabrication of Al2O3 films without any carbon contamination and Al 2p, Al 2s and O 1s peaks were appeared at binding energies of 74, 119 and 531 eV, respectively. Excellent insulating properties were observed for the Al2O3 films and optical transmittance of more than 85 % was recorded in the visible region. The experimental results suggest that polymeric materials are excellent candidates to be used as substrates in the fabrication of Al2O3 thin films through atomic layer deposition. 相似文献
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为了设计用超临界流体抗溶剂结晶(GAS)法制备葛根素的超细颗粒,用静态平衡法考察了超临界CO2溶胀过程中葛根素在乙醇溶液的溶解特性.实验结果表明,体系压力变化对溶解度的影响最为显著.同时,我们发现,伴随着体系压力的递增,溶液中葛根素浓度表现为先扬后抑的趋势,甚至大于其初始值.由此可知,GAS过程CO2兼有抗溶剂和萃取剂的双重功能:前者降低溶质的溶解度,后者则提高溶液浓度. 相似文献