边界条件对纤维素胆甾相聚集态结构的影响

乙基氰乙基纤维素／二氯乙酸溶液形成的胆甾相的聚集态结构随着浓度的变化会呈现出多种织构形态。不同的边界(基片面)取向条件，会对其胆甾相溶液的织构会产生影响。总体上，基片面垂直取向有利于螺旋轴平行于基片面(液晶分子层垂直基片面)的焦锥排列基片面平行取向则会抑制螺旋轴平行基片面的焦锥排列，而趋向于螺旋轴垂直基片面的平面排列。界面表面张力和随溶液浓度而增大的胆甾相扭转力能抑制边界取向作用对胆甾相聚集态结构的影响。     

液晶聚合物分子排列调控的研究进展

液晶的应用不仅仅局限于电视或电脑,具有光响应性的液晶在许多领域都存在应用,如平板显示、光学领域、光驱动设备以及许多正在发展的微科技领域. 液晶作为一种中间相的物质,既表现出了液体的流动性,又具有晶态的分子规整排列的性质. 液晶软物质材料具有许多有趣的性质,如自组装性质;长程有序的流动性;分子协同作用;双折射性质和物理性质（光、力、和电）的各向异性;外场诱导的表面分子取向;以及液晶弹性体的刺激响应性形变. 文中综述了具有不同液晶分子取向排列的液晶聚合物的刺激响应性形变,着重介绍了光取向技术诱导液晶分子取向的液晶聚合物的刺激响应性形变行为,并展望了未来液晶材料的设计在微流体和微型机器人领域的潜在应用.     

负性向列相液晶在LB膜上的取向及电光特性

报道了用花生酸生长的ＬＢ膜作液晶取向层，使负性向列相液晶ＭＢＢＡ在其上取得较好的垂直取向排列效果。并通过偏光显微镜利用锥光干涉效应，研究了这种取向排列．研究表明，在加电压后液晶受电场作用偏转具有一定的择优取向，取向方向与ＬＢ膜的生长提拉方向平行。同时，对其电光特性进行了测量。从测量显示出的典型电控双折射形电光特性曲线肯定了择优倾斜取向的存在。     

香豆素类液晶化合物的研究进展

香豆素材料由于具有荧光和光二聚作用,以及荧光量子产率高、Stokes位移大、光物理和光化学性质可调以及光稳定性好等优点,被应用于许多领域,如荧光材料、激光染料、光折射材料、非线性光学材料、采光材料以及液晶取向层材料等.香豆素类作为一种光敏性基团已被引入到液晶分子中,使液晶分子不仅具有自组装性质,同时具有优异的光电性质.该文综述了近年来含有香豆素光敏基团的液晶化合物的研究进展.     

新型介晶光致液晶取向剂的合成与性质

为了开发新型光致取向剂 ,通过硅氢化反应合成了一种新型的液晶高分子光致取向材料——对烯丙氧基肉桂酸对丙氧基苯酚酯接枝聚硅氧烷 (PSPAC)。并用示差扫描量热分析和偏光显微镜进行表征 ,确定其相变温度和液晶织构。热降解机理的红外研究表明这是一种热稳定性远远优于传统光致取向材料聚乙烯醇肉桂酸酯的新型液晶光致取向剂。线性偏振光聚合 (L PP)取向法实现了液晶分子良好的垂直和平行取向 ,实验结果同时也表明曝光后不同的液晶分子取向状态并不相同。     

用聚合物网络控制液晶分子取向

对在液晶材料中掺入２％的、经可见紫外光固化的聚丙烯酸酯单体进行聚合和在垂直于基片方向上施加一个合适的电场，获取沿摩擦方向一致取向的网络织构及用取向的聚合物网络实现控制液晶分子取向的研究做了报道，并阐述了聚合物网络与液晶的相互作用机理；根据液晶光透射率的计算公式，对实验结果进行了定量分析．     

大预倾角取向材料的合成

在超扭曲向列（ＳＴＮ）液晶显示器中，液晶分子的扭曲角为１８０～２７０°，为此要求液晶分子相对于基板表面有５～３０°的预倾角，这是通过在基板表面涂布聚酰亚胺并施以表面定向摩擦而实现。因此，表面取向层的获得及取向工艺是ＳＴＮ显示的关键技术之一。作者讨论了聚酰亚胺的化学组成及取向剂的因含量等因素对预倾角的影响。     

微接触印刷法制备新型液晶垂直取向膜

采用微接触印刷法在盖玻片表面制备了微米级沟槽状N′-β′-氨乙基-N-β-氨乙基-γ-氨丙基三甲氧基硅烷薄膜,通过在其表面组装Cu ²⁺制得了液晶垂直取向膜。当有机膦化合物甲基膦酸二甲酯(DMMP)气体通过薄膜表面时,液晶分子发生偏转;当新鲜空气通过时,液晶分子恢复垂直排列,从而实现对DMMP的定性检测。     

液晶取向技术

介绍了液晶光开关的基本原理及其在光通信和信息显示领域的应用.从取向层材料、取向原理、取向工艺等方面综述了几种液晶取向技术:摩擦取向技术、光控取向技术、倾斜蒸镀法以及LB膜法,并阐述其优缺点.最后对未来的取向技术做一个展望.     

向列型液晶中的光自聚焦和自散焦

从理论上推出:分子半行液晶膜面排列的向列型液晶由于光致重取向产生的折射率随光强增大而减小的结果将导致高斯光束的自散焦。而对于垂直膜面排列的液晶分子重取向则导致相反的结果,实验证实了这一理论结果。     

平行排列丝状液晶超短脉冲激励下的弯曲形变

用光学相位延迟法研究平行排列丝状液晶在超短脉冲激光作用下的瞬态弯曲形变，与垂直排列液晶相比，采用平行排列丝液晶可以不考虑取向致流，从而简化实验分析，结果表明，液晶在激光作用下会产生瞬态的弯曲形变，并伴着热效应，前者的弛豫时间为数十毫秒，后者的弛豫时间为数毫秘。     

含液晶基元的光控取向薄膜新型材料的制备及初步表征

合成了一种侧链上同时含有液晶基元、柔性间隔基和肉桂酰感光基团的新型液晶聚合物,用核磁共振(1H NM R)和傅里叶红外光谱(FT IR)确定了上述中间体的结构,并用热分析等手段研究了聚合物性能.经线性偏振紫外光聚合技术处理聚合物膜,通过检测照射前后聚合物薄膜透光率的变化可知,所制备的取向薄膜具有良好的定向能力,该聚合物是一类具有潜在应用价值的新型光控取向薄膜材料.     

超声作用下碳酸钙晶体的形态变化

为了解超声场对碳酸钙晶体形态的影响,揭示其作用机制,采用自行设计的超声设备(40 kHz,0.88W/cm2)来处理不同过饱和度的碳酸钙溶液,并比较有、无超声作用的碳酸钙晶体的形态和大小.研究结果表明:超声空化效应所产生的微观热量不仅能促进过饱和溶液中碳酸钙晶核的形成,迅速降低溶液的过饱和度,还能改变碳酸钙晶体的形态;经超声处理的碳酸钙过饱和溶液中形成了大量微小的碳酸钙晶体,其中绝大部分为文石,少量为细小方解石,它们长时间悬浮在溶液中;超声的机械效应对碳酸钙晶体形态的影响甚微.     

Stacking of conical molecules with a fullerene apex into polar columns in crystals and liquid crystals

Polar liquid crystalline materials can be used in optical and electronic applications, and recent interest has turned to formation strategies that exploit the shape of polar molecules and their interactions to direct molecular alignment. For example, banana-shaped molecules align their molecular bent within smectic layers, whereas conical molecules should form polar columnar assemblies. However, the flatness of the conical molecules used until now and their ability to flip have limited the success of this approach to making polar liquid crystalline materials. Here we show that the attachment of five aromatic groups to one pentagon of a C(60) fullerene molecule yields deeply conical molecules that stack into polar columnar assemblies. The stacking is driven by attractive interactions between the spherical fullerene moiety and the hollow cone formed by the five aromatic side groups of a neighbouring molecule in the same column. This packing pattern is maintained when we extend the aromatic groups by attaching flexible aliphatic chains, which yields compounds with thermotropic and lyotropic liquid crystalline properties. In contrast, the previously reported fullerene-containing liquid crystals all exhibit thermotropic properties only, and none of them contains the fullerene moiety as a functional part of its mesogen units. Our design strategy should be applicable to other molecules and yield a range of new polar liquid crystalline materials.     

金属酞菁LB膜的制备及结构表征

研究了金属酞菁化合物四（２，４－二甲基苯氧基）酞菁铜和四（２，４－二甲基苯氧基）酞菁镍在汽－液界面上的成膜特性，制备了相应的Ｌａｎｇｍｕｉｒ－Ｂｌｏｄｇｅｔｔ（ＬＢ）膜。利用紫外可见吸收及偏振紫外可见吸收谱，表征了ＬＢ膜中的酞菁分子主要以二聚体的形式相对于基片水平排列。以酞菁ＬＢ膜为取向层制成液晶盒，取向向列型液晶Ｅ＿７。通过偏光显微镜及锥光干涉系统，确定液晶分子在ＬＢ膜上的排列情况，并进行了电光测试，讨论了导致不同取向效果的机理。     

Crystallogeny fundamentals of the cholesterol gallstone

The nucleation mechanism and crystal growth process of the cholesterol gallstone are studied and a systematic theory expounded by crystallogeny is proposed. Normal feed and stone-forming feed were used to raise guinea pigs in the control and stone-causing groups respectively. The state and transformation of liquid crystal vesicles, the appearance of crystal nuclei, and the formation of microcrystal grains were observed under a polarizing microscope during the experimental period. It was found that the liquid crystal vesicles in the bile of the control group were small, scattered, and always existed as single forms, and no shaped gallstone crystals were formed. While in the stone-causing group, liquid crystal vesicles grew to larger ones, and then aggregated to form large liquid crystal cells. Solid crystal growth along the edge of these liquid crystal cells formed microcrystal grains. These demonstrated that bile liquid crystal vesicles form the basic nuclei of cholesterol gallstone. Heterogeneous nucleation is the common process in the formation of crystal nuclei and crystal growth.     

Crystallogeny fundamentals of the cholesterol gallstone

The nucleation mechanism and crystal growth process of the cholesterol gallstone are studied and a systematic theory expounded by crystallogeny is proposed. Normal feed and stone-forming feed were used to raise guinea pigs in the control and stone-causing groups respectively. The state and transformation of liquid crystal vesicles, the appearance of crystal nuclei, and the formation of microcrystal grains were observed under a polarizing microscope during the experimental period. It was found that the liquid crystal vesicles in the bile of the control group were small, scattered, and always existed as single forms, and no shaped gallstone crystals were formed. While in the stone-causing group, liquid crystal vesicles grew to larger ones, and then aggregated to form large liquid crystal cells. Solid crystal growth along the edge of these liquid crystal cells formed microcrystal grains. These demonstrated that bile liquid crystal vesicles form the basic nuclei of cholesterol gallstone. Heterogeneous nucleation is the common process in the formation of crystal nuclei and crystal growth.