电子显微镜研究分子筛的新进展

电子显微镜在沸石分子筛的研究中起着重要的作用.阐述了透射电子显微镜(TEM)和扫描电子显微镜(SEM)技术研究沸石分子筛的原理,描述了使用不同种类的电子显微镜剖析沸石分子筛的形态、尺寸、粒径分布等,并介绍了近年来电镜技术对沸石分子筛,特别是对新型功能介孔材料及手性介孔材料的研究进展.电子显微镜的发展将推动分子筛及纳米材料在选择性催化/吸附过程中的应用.     

Improving SEM Inspection Performance in Semiconductor Manufacturing Industry

Scanning electron microscope (SEM) station is one of the major quality control tasks in wafer manufacturing process. During the process of examining defects on a screen for a certain period of time, SEM inspectors frequently complain about visual fatigue problems. The purpose of the study was to evaluate the effect of wafer‐coating condition (noncoating treatment and gold‐coating treatment) and liquid crystal display (LCD) monitor size (14‐inch and 19‐inch monitor) from the aspects of objective visual fatigue measures (NPA and CFF), subjective eye fatigue rating, and inspection performance. Twelve SEM inspectors participated in this experiment. The results indicated that the treatment of gold‐coating wafer showed significant difference on reducing objective visual fatigue in NPA and CFF change. Using a 19‐inch LCD monitor also demonstrated the effect on reducing eye fatigue as well as improving inspection performance. The improvement of using a gold‐coating treatment wafer and a 19‐inch LCD monitor to reduce SEM inspectors' visual fatigue and to increase inspection performance is thus recommended. © 2012 Wiley Periodicals, Inc.     

Alkali-silica reactivity of some frequently used lightweight aggregates

Lightweight aggregates (LWAs) are frequently used in concrete as well as in thermally insulating mortars and grouts, so that information on their alkali-silica reactivity (ASR) is very important. Four LWAs—expanded vermiculite, expanded clay, expanded glass and perlite—were studied regarding their ASR, using the following test methods: the accelerated mortar bar test (ASTM C 1260), the rapid chemical test (ASTM C 289) and the combined scanning electron microscopy-energy dispersive X-ray technique (SEM-EDX). According to these methods, neither the expanded vermiculite nor the expanded clay exhibited any potential ASR. On the other hand, in the case of the aggregates containing a glassy phase (expanded glass and perlite), the results of SEM-EDX analysis showed serious decomposition of aggregate texture due to ASR, although no deleterious expansion was observed in the accelerated mortar bar test. Therefore, suitable test criteria for ASR need to be defined for LWAs of this type when the AMBT method is used, as has already been suggested for slowly reactive aggregates in Australia.     

Mechanical properties and crosslink density of rare earth‐modified high‐abrasion furnace‐filled powdered natural rubber

High‐abrasion furnace‐filled powdered natural rubber [P(NR/HAF)] has more advantages than traditional HAF‐filled bale NR (NR/HAF) because of its better environmental performance and easier processing quality, but its lower mechanical properties are disadvantageous. To improve the mechanical properties, rare earth‐modified HAF‐filled powdered NR [P(NR/HAF‐Ln)] (Ln = Sm,La,Pr) was prepared by means of coacervation–coprecipitation, using rare earth‐modified HAF as separant and filler. The effect on mechanical properties of P(NR/HAF‐Ln) vulcanizate exerted by the emulsifier/HAF ratio, powdering temperature, Ln/HAF ratio and type of Ln, and HAF content were studied. The results indicated that when optimum formulation, the mechanical properties of P(NR/HAF‐Ln) vulcanizate were better than P(NR/HAF) vulcanizate. In addition, the relationship of the apparent crosslink density and HAF content of P(NR/HAF‐Ln), P(NR/HAF), NR/HAF vulcanizates was also investigated, along with their SEM microphotographs of tensile fracture surface, which indicated that the excellent mechanical properties of P(NR/HAF‐Ln) vulcanizate was attributed to correct amount of Ln that could increase crosslink density and reinforce the interface structure of NR matrix/HAF‐Ln particle. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1755–1762, 2006     

老、中、青肾移植患者口服普乐可复后总胆红素、尿酸、服药天数的三维图像分析

研究分析老、中、青年肾移植患者服用普乐可复天数、总胆红素、尿酸的三维图像,使临床指标形象化显现,为预测疾病提供信息。将60岁以上老年患者、40~59岁中年患者与小于40岁青年患者分三组,采用MATLAB7.0做三维图像,分析图像特征并且对老年、中年、青年组图像进行比较。三维图像显示出各项指标间存在内在关系与个体差异。体内指标与服药天数相关,体内指标对临床预防疾病具有重要意义。     

An in situ Raman study of the intercalation of supercapacitor-type electrolyte into microcrystalline graphite

An initial Raman study on the effects of intercalation for aprotic electrolyte-based electrochemical double-layer capacitors (EDLCs) is reported. In situ Raman microscopy is employed in the study of the electrochemical intercalation of tetraethylammonium (Et₄N⁺) and tetrafluoroborate (BF₄⁻) into and out of microcrystalline graphite. During cyclic voltammetry experiments, the insertion of Et₄N⁺ into graphite for the negative electrode occurs at an onset potential of +1.0 V versus Li/Li⁺. For the positive electrode, BF₄⁻ was shown to intercalate above +4.3 V versus Li/Li⁺. The characteristic G-band doublet peak (E_2g2(i) (1578 cm⁻¹) and E_2g2(b) (1600 cm⁻¹)) showed that various staged compounds were formed in both cases and the return of the single G-band (1578 cm⁻¹) demonstrates that intercalation was fully reversible. The disappearance of the D-band (1329 cm⁻¹) in intercalated graphite is also noted and when the intercalant is removed a more intense D-band reappears, indicating possible lattice damage. For cation intercalation, such irreversible changes of the graphite structure are confirmed by scanning electron microscopy (SEM).     

Edge Contour Extraction in MR Image Using Edgeflow Contour Model

This paper presents a new model for edge extraction of MR images, based on curve evolution and edgeflow techniques. At first the model for curve evolution is constructed, which automatically detect boundaries, and change of topology in terms of the edgeflow fields, and then the numerical approximation of the model is introduced, which is based on semi-implicit scheme to speed up the proposed approach. Finally, the numerical implementation is present and the experimental results show that the proposed model successfully extracts the edge contours, regardless of the heavy noise.     

基于Tiff图像数字化档案的研究

Tiff文件格式是一个丰富的图像格式,可以支持多种图像,现在已经成为存储档案数字化图像的标准格式.现有的应用程序都可以很好的支持Tiff图像格式.本文从Tiff的结构、特性、分类等几个方面,对Tiff文件进行了详细的分析.在支持传真的Class-F分类基础上,通过配置Tiff标签和在图像数据区域附加图像描述信息,对基于Tiff图像的数字化档案进行研究,并把此研究应用于焊接培训中,并取得了预期的效果.     

基于灰度匹配的序列影像的目标跟踪研究与实现研究

为了达到特定目标跟踪的目的,对视频帧进行匹配算法的处理。通过利用灰度匹配的算法在平台上对简单背景下的目标进行跟踪,来显示进行目标基本跟踪过程。对目标坐标系的转换、运算的速度和使用的范围进行讨论。     

关于AUTO CAD在图形图像教学领域的多元结合应用

AUTO CAD是一款交互式计算机辅助设计以及绘图的软件,在传统的教学中很多学生都认为这款软件的学习十分困难,所以很难提起学习兴趣,还有一些学生学习了后面的知识就会忘记前面的知识,这就使得教学质量与效率很难提升。为此,教师应积极主动探索有效的教学方式,激发学生的ATUO CAD软件的学习兴趣,提升教学和学习的质量。本文就探讨ATUO CAD在图形图像教学领域的多元结合应用。