Synthesis of Single-Crystalline Silicon Nitride Nanobelts Via Catalyst-Assisted Pyrolysis of a Polysilazane

Recently, one-dimensional nanostructures have attracted extensive attention since they are potentially important for both applications and fundamental research. In this paper, we report the synthesis of ultra-long single crystal Si₃N₄ nanobelts via catalyst-assisted pyrolysis of polymeric precursors. The obtained products contain both α- and β-Si₃N₄ nanobelts, which are 50–100 nm in thickness, 400–1000 nm in width, and a few hundreds of micrometers to several millimeters in length. Different from previous techniques for synthesizing one-dimensional structures, the current nanobelts are synthesized through confined crystallization of an amorphous phase. A solid–liquid–gas–solid reaction/crystallization growth mechanism is proposed. The formation of nanobelts instead of nanowires is attributed to the anisotropy growth at an earlier stage.     

基于嵌入式系统开发平台的设计与实现

本文首先介绍了EVB2107评估板、评估板的系统开发工具和集成开发环境,然后对扩展板上各模块都从原理入手结合该模块要实现的功能说明其设计思想和实现原理,并就各模块驱动程序的编程思想及流程进行了论述。     

数字多用表的比例功能在电阻箱检测中的应用

本文提出了检测电阻箱的一种新方法--比例法.文章除介绍其原理和方法外,还对装置的不确定度进行了分析,并对比例法检测数据和数表法直接测量的检定结果进行比对.比例法检测电阻箱的特点是对标准器和辅助设备的要求低、工作效率高并可实现半自动检定.拥有数字多用表和标准电阻的检测部门可利用本方法.     

Fabrication of thick BOX SOI by Smart-cut technology

A SOI material with thick BOX (2.2 μm) was successfully fabricated using the Smart-cut technology. The thick BOX SOI microstructures were investigated by high resolution cross-sectional transmission electron mi-croscopy (XTEM), while the electrical properties were studied by the spreading resistance profile (SRP). Experimen-tal results demonstrate that both structural and electrical properties of the SOI structure are very good.     

葫芦岛蒙脱土的特征与催化活性

研究了葫芦岛蒙脱土的某些特征与催化活性。该蒙脱石的离子交换能力与层间距分别是７５ｍｅｑ／１００ｇ和１．５２９ｎｍ，对偏三甲苯的歧化、异构化以及偏四甲苯的脱甲基、异构化都具有催化活性。这些数据表明葫芦岛蒙脱土是一种有用的催化材料。     

最优布局中任意曲线状图形处理

介绍了适合于多类型、曲线状零件优化排料的图形处理数据结构和算法，并加以探讨和研究。以此思想所设计的系统运行结果良好。     

Investigation of elastic modulus of nanoporous alumina membrane

Nanoporous alumina membranes containing parallel regular pores of uniform size and normal to substrate surface were fabricated by anodically oxidizing high purity aluminum foils in acid solutions and their elastic modulus was investigated. The continuous out-of-plane displacement and current load of the porous membranes were obtained through bulge test combining real-time ESPI (electronic speckle pattern interferometry) observation system. Then the elastic modulus was calculated through an analytical model and the pore distortion after load was characterized by HRSEM (high resolution scan electron microscope). Measurement of mechanical properties indicates unusual mechanical behavior of these anodic alumina films compared with bulk alumina materials. This observation may help shed light on fracture mechanism of these films with nanopore arrays and bring further understanding on connecting of micro-meso structure and mechanical properties.     

机制整体型全纤维炉衬台车炉技术改造

针对第一拖拉机股份有限公司锻造厂１０ 号车间７＃ 台车炉存在的能耗高、生产效率低等问题,采用“整体型全纤维炉衬”的专利技术进行技术改造,以达到节能降耗的目的。     

水产品加工废水深度处理的试验

进行了用"生物接触氧化-微滤膜"组合工艺对水产品加工废水深度处理的试验研究.试验结果表明:在进水COD约900~1 200 ms/L,水力停留时间>16 h的情况下,平均出水COD<50 ms/t,达到再生水杂用水质标准.同时,研究探讨了处理过程中膜组件的污染及清洗问题,为实际工程中膜的运行提供了必要的参考.     

基于ENR数据分析的中国大型设计院发展趋势

中国勘察设计行业正面临着全球化、中国经济结构转型和国家实施“走出去”的开放战略等诸多机遇与挑战,所以对未来发展有一个相对准确的分析和预测有着很重要的意义.本文通过对近七年来ENR 发布数据的分析,找到了世界大型设计公司与国际化之间存在的一些联系,然后通过对不同国家和地区设计公司之间的比较,结合各自的国情和经济发展水平,给出了未来中国大型设计院可能的发展趋势预测,即中国大型设计院依靠巨大的国内市场,在体量上会很快跻身世界大型设计院的“第一梯队”,但与西方竞争对手相比,在国际市场仍然存在相当大的差距,如果不能尽快建立完善的全球网络和平台,中国大型设计院有可能止步于海外中高端市场.