An improved practical Pd/C‐catalyzed Sonogashira cross‐coupling reaction for the synthesis of liquid crystals of trans‐cyclohexyltolans

An improved practical synthesis of liquid crystals of trans‐cyclohexyltolans by Sonogashira cross‐coupling reaction of 1‐iodo‐4‐(trans‐4‐alkylcyclohexyl)benzene with aromatic terminal alkynes in the presence of Pd/C (palladium on activated carbon) as low as 0.03 mol% of Pd and CuI (2 mol%) in a mixture solvent of acetone–water (5:2 in volume) is described. The liquid crystals could be obtained in high yields as a solid with excellent purity by simple filtration, and the filtrate could be reused several times while still retaining high catalytic activity. Copyright © 2010 John Wiley & Sons, Ltd.     

脑外伤患者血浆脂联素的检测及临床意义

目的 探讨脑外伤患者血浆脂联素水平的变化规律及与脑外伤严重度的相关性。方法 选取86例重型脑外伤患者 和86例健康体检者，分别于入院时、入院后第1、2、3、5、7天和体检时清晨空腹抽取静脉血，ELISA 法测定血浆脂联素水平。结果 脑外伤后血浆脂联素水平6h内升高，24h到达高峰，后逐渐下降，入院时、入院后第1、2、3、5、7天的血浆脂联素水平均明显高于健康对照组（均P＜0.01）；蛛网膜下腔出血、环池消失、中线移位（＞5mm）和瞳孔散大患者各个时间点血浆脂联素水平显著高于其对照组（均P＜0.01）。入院时格拉斯哥昏迷评分与各个时间点血浆脂联素水平均呈负相关（均P＜0.01）。结论 脑外伤后血浆脂联素水平升高，与脑外伤严重度显著相关。     

肛周脓肿局部组织及外周血中IL-22 的表达及临床意义

目的 探讨细胞因子IL-22 在肛周脓肿局部组织及外周血中的表达和意义。方法 选取50例肛周脓肿患者（肛周 脓肿组）和50例无感染的混合痔患者（对照组）,两组患者均行手术治疗,并术中留取病变组织标本。术后观察患者转归,免疫组织化学法检测IL-22 表达、RT-PCR 法检测外周血单核细胞中IL-22 mRNA 的表达,观察IL-22 表达的变化及其与患者临床病理特征之间的关系。结果 IL-22在肛周脓肿组的表达阳性率高于对照组（P＜0.01）;肛周脓肿组根据不同转归分为治愈组、脓肿复发组、肛痿组,3 组患者IL-22 表达阳性率比较,治愈组显著降低,而肛瘘组最高（P＜0.01）。肛周脓肿组外周血单核细胞中IL-22 mRNA表达水平显著高于对照组（P＜0.01）;在肛周脓肿组中随着疾病的进展,肛瘘组患者外周血单核细胞中IL-22 mRNA表达水平显著高于治愈组（P＜0.01）。肛周脓肿组中IL-22的表达与患者性别、年龄均无关（均P ＞0.05）,而与脓肿直径（P＜0.01）、创面愈合时间（P＜0.05） 及进展为肛瘘有关（P＜0.05）。结论 IL-22在肛周脓肿局部组织及外周血中表达增强,在其发病机制中起了重要作用。     

CuCl-catalyzed cycloaddition of 1,3-butadiynes with primary amines: an atom-economic process for synthesis of 1,2,5-trisubsituted pyrroles

1,3-Butadiynes underwent inter- and intramolecular double hydroamination with primary amines in the presence of CuCl at 100 °C to afford 1,2,5-trisubsituted pyrroles in good to high yields.     

Selenium-ligated palladium(II) complexes as highly active catalysts for carbon-carbon coupling reactions: the Heck reaction

Three selenium-ligated Pd(II) complexes were readily synthesized and shown to be extremely active catalysts for the Heck reaction of various aryl bromides, including deactivated and heterocyclic ones. The catalytic activity of the selenide-based Pd(II) complexes not only rivals but vastly outperforms that of the corresponding phosphorus and sulfur analogues. Practical advantages of the selenium-based catalysts include their straightforward synthesis and high activity in the absence of any additives as well as the enhanced stability of the selenide ligands toward air oxidation.     

HL-1装置的X射线测量

本文叙述了HL-1装置的X射线测量。结果表明,电子温度随着等离子体电流通道的缩小而升高,其典型值为480eV。稳定放电的软X射线扰动幅度大约是总强度的15％,锯齿振荡周期约为2ms。与磁探针信号比较,明显看到了内、外模之间的耦合关系。多次放电清洗了真空空器壁,含水量下降;硬X射线测量表明,逃逸产生率减小。     

变栅距光栅实现啁啾脉冲光谱整形

为了充分利用放大介质的增益带宽,获得脉宽更短,功率更高的输出脉冲,需要将输入到主放大链的种子脉冲进行光谱整形来补偿放大过程中的增益窄化效应。提出了利用变栅距反射光栅实现中心波长1053nm,谱宽6nm啁啾脉冲的光谱整形。运用严格的光栅衍射耦合波理论分析光栅的衍射特性,发现该方案不会引入相位畸变。分别计算和分析了刻槽深度、入射角大小、光栅周期以及入射光波长的变化对衍射效率的影响,通过选取适当的光栅参量可获得0.5%~84%的光谱调制深度。     

Fuzzy relational equations with min-biimplication composition

This paper discusses fuzzy relational equations with min-biimplication composition where the biimplication is the biresiduation operation with respect to the ?ukasiewicz t-norm. It is shown that determining whether a finite system of fuzzy relational equations with min-biimplication composition has a solution is NP-complete. Moreover, a system of such equations can be fully characterized by a system of integer linear inequalities and consequently its solution set can be expressed in the terms of the minimal solutions of this system of integer linear inequalities.     

基于8-羟基喹啉及其衍生物的有机小分子电致发光材料

有机电致发光器件因驱动电压低、亮度和效率高等优点,已经成为最具潜力的平板显示技术。自以8-羟基喹啉铝为发光材料制备双层有机电致发光器件开始,科研人员在发光材料设计合成方面做了大量工作并取得了重大研究进展。在小分子荧光材料中,8-羟基喹啉及其衍生物为配体的有机金属配合物因合成方法简单、发光效率和亮度高、成膜性好等优点而被广泛应用。本文简述了有机电致发光器件的优点、结构及工作原理,重点介绍了基于8-羟基喹啉及其衍生物为配体的有机小分子电致发光材料的研究现状。从分子设计的角度出发,旨在总结8-羟基喹啉及其衍生物为配体的有机小分子电致发光材料对有机电致发光器件性能的影响,包括:以8-羟基喹啉为单一配体的有机金属配合物展示了良好的电子传输能力、亮度高且可作为基质材料等卓越的特性;通过对8-羟基喹啉的苯氧环或吡啶环进行修饰可以调节电致发光颜色;混合配体的使用可以增加玻璃化温度、改善薄膜形貌进而提高器件的效率和稳定性。最后,对该领域存在的问题和有机电致发光材料的应用前景作了评述。