Decoration of disclinations by solidification-induced band texture and focal-conic texture for a low-molar-mass liquid crystal

Two decoration techniques, solidification-induced band texture decora tion and focal-conictexture decoration, have been established to exhibit the director field of disclinations in a low-molar-mass methacrylate liquid crystal. The disclinations with strength s = 1/2 and s = ±1 are observed by the two decor ation methods. For the solidification-induced band texture decoration, the molecular orientation is perpendicular to the direction of the band. While for focal- conictexture decoration, it has been proved by the results of IR dichroism that the direction of the director is parallel to the direction of the focal-conic. Therefore, the sketch map of the molecular director filed can be mapped according to the morphological pattern of the solidification-induced band textureor focal-conic texture.     

45钢固体粉末法稀土、硼、铬、铝共渗工艺研究

研究了RE_Mg合金对固体粉末法硼、铬、铝共渗层成分、组织和性能的影响 .发现随着RE_Mg合金加入量的增加 ,渗层中Al2 O3的量不断增多 ,当RE_Mg合金加入量为 5 %时 ,渗层中出现连续致密分布的Al2 O3黑区组织 ,对此进行了性能测试和机理探讨     

一种新型彩色三维光学成像系统

提出一种新型三维彩色光学数字成像系统。此系统利用投影结构光对现实世界中的物体进行数字化，同时得到对应的彩色纹理。详细介绍了系统的硬件设计和软件体系结构设计，得到物体彩色纹理的两种不同方法；直接获取和从编码条纹中提取，给出了用该系统得到的实验结果并简单评价了系统的性能。此系统在反求工程、影视制作、三维游戏制作、医学应用等方面有远大的应用前景。     

基于移动Agent技术的医学图像检索方法

针对现有医学图像检索方法中，检索算法速度较慢、准确性较低以及远程检索时占用大量带宽等问题，设计并实现了一种基于移动Agent技术的医学图像检索方法，重点讨论了该方法实现的关键技术，包括提升框架下的M带整数小波变换和提取多通道纹理特征的检索算法．模拟实验结果表明，该方法实时性较强，占用网络带宽较少，采用的算法运算速度提高近10倍、运算复杂度降低约50％，提取的纹理特征能充分表达图像内容，较好地满足了医学图像的检索要求，实现了对医学图像库快速较准确的检索．     

Statistical approach to light scattering from deformed textured heterogeneous polymer materials

A statistical theory of light scattering from deformed isotropic and textured heterogeneous polymer materials is formulated. Two types of textured structures are analyzed: assemblies of optically isotropic and anisotropic rods and a spatially anisotropic distribution of isotropic spherical inclusion centers. The small-angle H_v light-scattering patterns are calculated. The appearance of scattering from isotropic rods and spheres in deformed materials has been demonstrated. The changes of the H_v scattering patterns as a function of elongation and strucuture parameters are discussed. © 1993 John Wiley & Sons, Inc.     

基于小波变换及布朗分形模型的纹理分割

在研究小波变换及布朗分形模型的基础上，定义了水平分维数，垂直分维数，对角分维数，并将它们作为纹理特征量来实现纹理的分割．实验结果表明，这些特征量能够很好地反映纹理特征，从而分割时不需有关图象中纹理类别的先验信息，较以往方法在准确度和计算复杂程度上都有很大提高．     

FRS-XRSA与SAXS研究硬弹性聚丙烯的结晶度、取向与超结构Ⅲ应变与回复

应用全倒易空间Ｘ 射线散射理论分析（ＦＲＳ ＸＲＳＡ）与ＳＡＸＳ研究了ＨＥＰＰ在应变（ε）与回复（Ｒ）过程中结晶、取向与超结构的变化．结果指出，ε可以诱发结晶，但当ε≥３０％后，结晶度（ＸＷＣ）趋于不变：ε可以导致晶粒破碎；ε与Ｒ对取向分布与平均取向基本上无影响，这符合片晶平行分离模型，而非叶簧弯曲模型；发现，在ε≤３０％时，层状片晶的分离为主要过程，而当ε＞３０％后，则分离的片晶会发生断层滑移；ε可以诱发微孔，类似地当ε＞２０％，微孔尺寸亦趋不变．从凝聚态结构阐明了ＨＥＰＰ在ε Ｒ过程中不同阶段的结构变化     

胆甾液晶／聚合物多组分体系的结构与性能研究（Ⅲ）──ChN／poly（MMA－CO－BMA）混合体系的形态结构

应用Ｘ射线衍射、偏光显微镜及电子显微镜研究了胆甾液晶与甲基丙烯酸甲酯（ＭＭＡ）─甲基丙烯酸丁酯（ＢＭＡ）无规共聚物共混体系的形态结构。研究了体系的结晶态及液晶态的行为和共聚物含量及组成对光学织构的影响。     

Influence of the texture of chromia catalysts on their activity in synthesis of 2-methylthiophene

The texture of Cr₂O₃-K₂O/Al₂O₃catalysts containing oxides of rare earth elements (REE) was studied. The catalysts are used for the synthesis of 2-methylthiophene by the reaction of H₂S with n-pentane or piperilene. The heterocyclization of n-pentane is a consecutive reaction involving a step of dehydrogenation of initial hydrocarbon. At this step the texture of the catalyst affects the yield of 2-methylthiophene. The yield of 2-methylthiophene obtained from piperilene and I₂S is independent of the catalyst texture.     

Influence of the activation temperature on structural and textural properties of NiMo/Al2O3 hydrodesulfurization catalysts

Investigations of a commercial NiMo/Al₂O₃ hydrodesulfurization (HDS) catalyst are directed towards optimization of the activation procedure of HDS catalyst concerning active phase formation and thermal stability. Structural and textural data obtained with XRD, IR-FTIR, XPS and LTNA reveal that the optimal temperature for the formation of active species on the catalyst surface and an appropriate pore structure is 300°C.