闪光灯泵浦Nd3+:GGG激光特性研究

用闪光灯泵浦掺钕钆镓石榴石(Nd^3 ：GGG)激光晶体，研究了脉冲宽度0．5ms、1ms、1．5ms和2ms的放电泵浦下激光输出，实验获得了1．92J的最大激光能量．     

DIRECT RESONANCE OF TURBULENT BOUNDARY LAVER OVER COMPLIANT WALLS

１．　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｍａｉｎｇｏａｌｏｆｔｈｉｓｐａｐｅｒｉｓｔｏｅｘｐｌｏｒｅｔｈｅｐｏｓｓｉｂｉｌｉｔｙｔｏｌｅａｒｎｍｏｒｅａｂｏｕｔｔｈｅｍｅｃｈａｎｉｓｍｏｆｔｕｒｂｕｌｅｎｔｂｏｕｎｄａｒｙｌａｙｅｒｆｌｏｗｉｎｔｅｒａｃｔｉｏｎｓａｎｄｉｔｓｅｆｆｅｃｔｓｏｎｃｏｍｐｌｉａｎｔｗａｌｌｐｅｒｆｏｒｍａｎｃｅ．Ｔｈｅｒｅａｒｅｃｅｒｔａｉｎｐｒｅｒｅｑｕｉｓｉｔｅｃｏｎｄｉｔｉｏｎｓｔｏｆｕｒｔｈｅｒｔｈｅｓｔｕｄｙｏｎｔｈｅｍｅｃｈａｎｉｓｍ，ｉ．ｅ．ｔｈｅｃｏ…     

延迟破胶及强制裂缝闭合技术的研究及应用

采用延迟破胶技术,在压裂施工过程中加入不同浓度的胶囊破胶剂,利用它的延缓释放特性,使植物胶压裂液耐温、耐剪切稳定性增强,并且可以在不造成压裂液的流变性、滤失性和携砂性等过早丧失的前提下高浓度使用胶囊破胶剂。该技术与常规破胶技术相比,延缓释放率达50%,能更有效地清除液体残渣,减少压裂液对储层的伤害。同时由于有延缓破胶的特性,放喷采用相应的措施,可以降低支撑剂沉降速度,形成较好的沉砂剖面,提供高的裂缝导流能力,并且可以降低滤饼和压裂液残渣的伤害。     

Impedance spectroscopy of ultrafine-grain SnO2 ceramics with a variable grain size

The impedance spectra of nanocrystalline SnO₂ ceramics with an average grain size d ranging from 3 to 43 nm were investigated in the frequency range 1–10⁶ Hz at temperatures from 25 to 300°C in a dry oxygen atmosphere. Analysis of the experimental data by the graphoanalytical method made it possible to separate the contributions of grain bulk and grain boundaries to the conductivity. It is shown that the samples investigated can be arbitrarily divided into two groups with respect to the character of their conductivity. For the samples with an average grain size d < 25 nm, the charge transfer processes are almost completely determined by the grain boundaries. In samples with a larger grain size, the contribution of grain bulk to the conductivity is comparable with that of grain boundaries.     

Formation of C49-TiSi2 in flash memories: a nucleation controlled phenomenon?

The formation of Ti silicides has been examined in flash memories with 0.25 μm linewidth by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. It has been observed that, after the first rapid thermal process and the selective metal etch, there is no silicide on the source and on a majority of drain contacts while C49-TiSi₂ is found on the gate. A pre-amorphisation implant increases drastically the formation of C49-TiSi₂ in the drain zone while modifications of annealing conditions have little impact. These results indicate that the formation of C49-TiSi₂ is most likely controlled by nucleation and that this nucleation is sensitive to both the width and the length of the reaction zone. The formation of a Ti rich silicide may play an important role in this nucleation by decreasing the driving force for the formation of C49-TiSi₂. Curiously enough, the formation of C49-TiSi₂ appears thus as a major concern for the salicide process in flash memories.     

国产CN—31催化剂与ICI65—2催化剂工业应用的比较

国产轻油预转化催化剂与进口催化剂相比,具有性能相当、价格低廉、供应方便等优势。国产预转化催化剂需在较高的液空速、温度较低的条件下实现烃类转化反应,生成含甲烷60%以上的富气。采用国产催化剂能明显反映性能价格比。文章对两种催化剂进行了工业应用比较和分析。     

天然气的储存

随着能源结构的调整,天然气在一次能源中的比重逐步增大,天然气的储存成为人们日益关注的课题,作者就此作一综述。     

卫星包装箱的随机隔振优化分析

用钢丝绳隔振器将卫星包装箱支承在运输车上,将卫星与车辆简化为二自由度体系,优化分析了在随机路面上行驶时使包装箱响应最小之隔振参数,对实测得到的钢丝绳减振器的非线性迟滞性能作了描述,提出了统计线性化分析的方法。     

NUMERICAL SIMULATION OF PARTICLE SEPARATION IN AN OIL-SAND SEPARATOR

ＮＯＴＡＴＩＯＮＳＡ　Ａｒｅａｏｆｉｎｌｅｔ ,ｍ2ａ　Ｃｅｎｔｒｉｆｕｇａｌａｃｃｅｌｅｒａｔｉｏｎ ,ｍ2 /ｓｉ　Ｇｒｉｄｏｆａｘｉａｌｄｉｒｅｃｔｉｏｎｍｌ 　ＭａｘｉｍｕｍｇｒｉｄｎｕｍｂｅｒｏｆｒａｄｉａｌｄｉｒｅｃｔｉｏｎＱ　Ｆｌｕｉｄｍａｓｓｒａｔｅ ,ｍ3/ｓＲｃ 　Ｍａｘｉｍｕｍｒａｄｉｕｓｏｆｃｙｃｌｏｎｅ ,ｍＲｅ　Ｒｅｙｎｏｌｄｓｎｕｍｂｅｒｒ　Ｄｉｍｅｎｓｉｏｎｌｅｓｓｒａｄｉａｌｄｉｓｔａｎｃｅｔ　Ｄｉｍｅｎｓｉｏｎｌｅｓｓｔｉｍｅｕ　Ｄｉｍｅｎｓｉｏｎｌｅｓｓａｘｉａｌｖｅｌｏｃ…     

同步辐射X射线光刻掩模镀金工艺的研究

介绍了利用北京正负对撞机(BEPC)同步辐射X射线光刻装置,进行LIGA工艺技术深结构光刻实验研究,详细论述了X射线光刻使用的掩模制备过程及掩模镀金工艺,在国内最早曝光出直径为400μm、厚为27～45μm的三维立体齿轮胶图形。