Investigation of silicon on insulator fabricated by two-step O+ implantation

In this paper, we investigated the dose window of forming a continuous buried oxide (BOX) layer by single implantation at the implantation energy of 200 keV. Then, an improved two-step implantation process with second implantation dose of 3×10¹⁵ cm^?2 was developed to fabricate high quality separation by implanted oxygen (SIMOX) silicon on insulator (SOI) wafers. Compared with traditional single implantation, the implantation dose is reduced by 18.2%. In addition, the thickness and uniformity of the BOX layers were evaluated by spectroscopic ellipsometry. Defect-free top Si as well as atomic-scale sharp top Si/buried oxide interfaces were observed by transmission electron microscopy, indicating a high crystal quality and a perfect structure of the SOI fabricated by two step implantation. The top Si/BOX interface morphology of the SOI wafers fabricated by single or two-step implantation was also investigated by atomic force microscopy.     

Multi-threshold second-order phase transition in laser

We present a theory of the multi-threshold second-order phase transition,and experimentally demonstrate the multi-threshold secondorder phase transition phenomenon.With carefully selected parameters,in an external cavity diode laser system,we observe secondorder phase transition with multiple(three or four) thresholds in the measured power-current-temperature three dimensional phase diagram.Such controlled death and revival of second-order phase transition sheds new insight into the nature of ubiquitous secondorder phase transition.Our theory and experiment show that the single threshold second-order phase transition is only a special case of the more general multi-threshold second-order phase transition,which is an even richer phenomenon.     

Identification of AtSM34, a novel tonoplast intrinsic protein-interacting polypeptide expressed in response to osmotic stress in germinating seedlings

Aquaporins are implicated in a wide variety of plant physiological processes, although the mechanisms involved in their regulation are not fully understood. To gain further insight into the regulatory factors involved in this process, we used a yeast two-hybrid system to screen for potential binding partners to the Arabidopsis tonoplast intrinsic protein (TIP) AtTIP1;1. This was the first protein identified to be associated with high water permeability in vacuolar membranes from Arabidopsis thaliana. Using ...     

Power law and small world properties in a comparison of traffic city networks

We analyze the statistical properties of the urban public bus networks of two cities (Beijing and Chengdu) in China. To this end, we present a comprehensive survey of the degree distribution, average path length, and clustering of both networks. It is shown that both networks exhibit small world behavior and are hierarchically organized. We also discuss the differences between the statistical properties displayed by the two networks. In addition, we propose a weight distribution approach to study the passenger flow through the public bus networks we considered. A hierarchical structure is observed here also.     

数据服务中间件中数据表示的实现技术分析

针对数据服务中间件进行数据表示时普遍采用的视图和主从式数据集等技术,分析了影响它们执行效率的因素,并采用动态生成SQL命令和限定基础数据集大小的处理方式大大降低了数据提取和重组的时间开销,有效地提升了数据服务中间件的执行效率,实现了对客户应用数据请求的快速响应.     

掺加降粘剂Sasobit对沥青指标影响的研究

近年来改性沥青在道路工程的大量使用,满足了工作性要求,却在施工过程中产生了大量烟尘等废弃物。而降低拌和温度是较好的办法,于是出现了温拌技术。该文以新疆克拉玛依90#A级沥青为研究对象结合温拌技术,研究掺加不同剂量的Sasobit对沥青的四种组分的影响及由此引起的变化,以确定Sasobit的合理掺量。     

条斑紫菜与坛紫菜挥发性风味的电子鼻分析

【目的】利用电子鼻技术区分条斑紫菜(Pyropia yezoensis)与坛紫菜(Pyropia haitanensis)的原藻及其制品。【方法】应用18个金属氧化型气体传感器并通过风味雷达图和主成分分析法对2种紫菜的挥发性风味进行轮廓性分析。【结果】两种方法分析原藻及其制品均显示条斑紫菜和坛紫菜的气味轮廓与敏感物质类型存在差异;相比紫菜原藻,各制品间的气味轮廓较为一致。【结论】电子鼻技术可以区分条斑紫菜与坛紫菜挥发性风味,原藻及其制品均有明显差异。加工过程使得产品挥发性风味趋于统一。     

滇黔桂结合部旅游竞合背景下的百色市旅游资源开发

以滇黔桂结合部旅游资源禀赋的基本状况为背景,对广西百色市的旅游资源及其特色,旅游业发展中存在的问题进行讨论和分析,并以此为基础,对滇黔桂结合部旅游合作与发展中的百色市旅游资源开发提出初步的意见和建议。     

通用报表系统的设计思想

介绍通用报表系统的主要设计思想，并着重叙述了需解决好的三个问题：表格存储；数据关系描述；表格输出中横表头的自动生成。     

FPGA／CPLD可编程逻辑器件的在系统配置方法

讨论了基于SRAM技术的CPLD／FPCA可编程逻辑器件的编程方法，并以ALTERA公司FLEX10系列器件为例，提出了一种利用微处理器对可编程逻辑器件进行在系统多方案配置的实用方法。该方法成本低廉、简单易行，能在系统复位或上电时自动对器件编程，不仅有效的解决了基于SRAM的CPLD／FPGA器件掉电易失性的问题，而且使单一芯片可以具有多种逻辑功能，实现了该类器件逻辑功能的在系统多方案的灵活配置。