关键词： 水煤浆   加压气化   高铬耐火材料   气化炉   高铬砖   显微结构   损毁机理  

摘要： 采用扫描电镜和能谱分析方法 ,分析了水煤浆加压气化炉用高铬砖渣蚀前后的显微结构和相组成 ,探讨了主要损毁机理。结果表明 :煤熔渣与砖反应和渗透引起砖组成的改变 ,从而导致砖的结构剥落和强度弱化是砖损毁的主要原因 ;LIRR -HK90砖的显微结构呈网络状镶嵌结构 ,直接结合程度高 ,与渣反应可生成 (Mg ,Fe) (Al,Cr,Fe) 2 O4 复合尖晶石致密带 ,阻止了渣的进一步渗透 ,减缓渣蚀速度和结构剥落 。

关键词： 微结构   电沉积   铁纳米线   单晶   模板合成   磁性纳米线   磁性能  

摘要： 铝在硫酸溶液中经直流阳极氧化,得到多孔铝阳极氧化膜（AAO）.以AAO膜为模板,通过交流电沉积的方法,在 AAO模板孔内成功组装了Fe纳米线、TEM分析表明,Fe纳米线的长度约为2.5μm,其长度分布十分均匀;粗细均匀,直径约为25nm XRD实验分析证实,所制备的Fe纳米线为α-Fe.选区电子衍射（SAED）实验分析表明α-Fe纳米线具有单晶结构.

关键词： 真空断路器   机械特性测量   在线测量   光栅传感器  

摘要： 真空断路器机械特性的在线测量能够准确地提供其工作时机械结构方面的信息 ,利用光栅传感器结合单片机数据采集及处理系统进行非接触在线测量具有速度快、精度高、成本低、信号易于处理等一系列优点 ,很适合在线测量 ,具有良好的实用价值和应用前景。

关键词： 镜面反射   纳米氧化层   自旋阀   显微结构   计算机   硬盘   磁盘读出磁头  

摘要： 巨磁电阻（GMR）多层膜自发现以来，自旋极化电子的传输过程一直是凝聚态物理研究的热点。如何进一步改进材料，提高巨磁电阻效应，已成为自旋阀在计算机硬磁盘读出磁头等重要信息处理器件方面应用的关键问题。最近，通过将自旋阀的部分被钉扎层和自由层进行氧化处理，引入厚度约为1nm的氧化层薄膜(NOL, nano-oxide layer)，可成倍地提高自旋阀的巨磁电阻（GMR）比率。这一发现引起了国际自旋电子学研究领域的广泛关注。

关键词： Si-C-Nnp/Si3N4复合材料   力学性能   Si-C-N纳米微粉   显微结构   氮化硅   碳化硅   纳米复相陶瓷  

摘要： 以 Si- C- N纳米微粉为增强相 ,Si3N4 为基相 ,采用热压的方法制备了 Si Cp/ Si3N4 纳米复相陶瓷。应用扫描电镜 (SEM)、高分辨透射电镜 (HRTEM)对其结构进行了观察 ,并讨论了结构与性能之间的关系。结果表明 ,所得的 Si Cp/ Si3N4 复相陶瓷的室温力学性能比氮化硅单相陶瓷有较大的提高 ,而 135 0℃断裂韧性达 14 .6 6 MPa· m1 / 2 。Si C微晶在晶粒内和在晶界玻璃相内的钉扎作用是材料高温性能提高的主要因素。

关键词： Nanostructured materials  

摘要： The synthesis microstructure and photoluminescent properties of nanoparticles of pristine and Mn2+-activated (Zn,Cd)S were investigated. the nanoparticles were synthesized via a chemical colloidal or solvothermal route. The TEM and SEM imaging, and x-ray diffraction (XRD) analysis were used for the study of the nanoparticles. The average size of the nanoparticles was found to be ca. 5-10 nm in diameter. In the nanocrystalline (Zn,Cd)S:Mn2+ phases, the absorption of (Zn,Cd)S was found to dominate and no absorption due to Mn2+ was observed.

关键词： 热处理温度   铟锡氧化物   纳米粉   显微结构   晶化温度   化学共沉淀法   薄膜  

摘要： 采用化学共沉淀法制备了铟锡氢氧化物纳米粉 ,对其热处理前后的粉体进行了XRD和TEM分析 ,结果表明 :未热处理的为铟锡氢氧化物 ,2 0 0℃热处理后铟锡氢氧化物部分晶化 ,30 0℃热处理后全部转变成晶态 ,然后随着温度升高逐渐转变为具有立方结构的铟锡氧化物纳米粉 ;6 0 0℃热处理 1h后粉末粒度为 5～ 10nm ,铟锡质量比接近 9∶1.铟锡氧化物颗粒接近球形 。

关键词： cellular water structure   cellular ultrastructure   cryofixation   freeze-drying   gelatine   hydration of macromolecules   immunocytochemistry   ion localization   Lowicryl   mitochondrial membranes   Spurr's resin   transmission electron microscopy  

摘要： Transmission electron micrographs of different biological material, cryofixed, freeze-dried and embedded in Spurr's resin, in Epon, or in Lowicryl, are presented. The structure preservation obtained either without or with application of chemical fixatives after drying showed that freeze-dried embedded specimens are particularly well suited for new morphological, immunocytochemical and microanalytical studies aimed at detecting the life-like subcellular distribution of mobile macromolecules and ions. The results also indicate that the removal of cell water by freeze-drying from the areas of best cryofixation is relatively slow. Ultrathin sections of well cryofixed biological material embedded after freeze-drying in Spurr's resin or Epon reveal cellular plasma phases with very fine granularities and well defined membranes in negative contrast. This may be due to the preservation of the original structure of cellular macromolecules with a considerable amount of their hydration water. Sublimation studies with differently hydrated and cryofixed macromolecules are suggested to settle this issue.

关键词： transmission electron microscopy mechanochemical treatment   indium oxide  

摘要： Changes in the microstructure of indium oxide with the mechanochemical treatment have been examined using transmission electron microscopy. Grinding together with alumina powder produced fine particles of the indium oxide with a sub-nanometric size, and the effective surface area markedly increased. The increase of surface promoted the dissolution of indium from the sample soaked in acids, and therefore the yield of the precious element was much pronounced. On the basis of this microstructural change. some incomprehensible phenomena related to this process, e.g. abnormal decrease in diffraction intensity of the indium oxide in powder X-ray diffraction, could be explained reasonably. (C) 2002 Elsevier Science B.V. All rights reserved.

关键词： grain boundary engineering   microstructure   themomechanical processing   annealing  

摘要： Grain boundary engineering comprises processes by which the relative fractions of so-called special and random grain boundaries in microstructures are manipulated with the objective of improving materials properties such as corrosion, creep resistance, and weldability. One such process also referred to as sequential thermomechanical processing (TMP), consists of moderate strains followed by annealing at relatively high temperatures for short periods of time. These thermomechanical treatments on fcc metals and alloys with low to medium stacking fault energies result in microstructures with high fractions of Sigma3(n) and other special boundaries, as defined by the coincidence site lattice (CSL) model. More importantly, the interconnected networks of random boundaries are significantly modified as a consequence of the processing. The modifications in the grain boundary network have been correlated with post-mortem electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) observations of the deformed and annealed states of the material. The evolution of the microstructure to a high fraction of Sigma3(n) boundaries is correlated with the decomposition or dissociation of immobile boundaries during annealing. This is evidenced by TEM observations of the decomposition of relatively immobile boundaries into two components, one with very low energy and thus immobile, and the other a highly mobile boundary that migrates into neighboring areas of higher strain levels. The formation of low-energy grain boundaries through this mechanism and its effect on boundary network topology is discussed within the context of grain boundary engineering and linked to known microstructural evolution mechanisms. (C) 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.