CSCW多媒体同步与协同模型

介绍了ＣＳＣＷ和群件基本概念,讨论了ＣＳＣＷ和群件的关键技术和发展现状,提出了一种基于多媒体同步关系的面向群件的多媒体同步协同模型,并讨论了初步实现技术和方案。     

环己酮-水分离新方法的研究

针对工业上传统的蒸馏法分离环己酮－水体系能耗过大的问题,研究了含盐类的复合萃取剂对该体系的萃取分离效果。结果表明,ＬｉＣｌ、ＭｇＣｌ２能明显改变环己酮与水之间的互溶度,大幅度提高复合萃取剂对组分的萃取分配系数和选择性系数,达到分离提纯环己酮的目的。进一步研究了萃取工艺参数对分离效果的影响。经初步热量衡算表明：应用本法分离环己酮－水比传统的蒸馏法节省能耗约２５％。     

剪切型建筑结构抗共振抗震设计

通过将剪切型建筑结构的固有频率调离场地的卓越频率区域,提出一种抗共振抗震设计方法。数值算例说明该方法是很有效的。     

Highly regioselective rearrangement of 2-substituted vinylepoxides catalyzed by gallium(III) triflate

Gallium(III) triflate catalyzed the rearrangement of 2-substituted vinylepoxides into beta,gamma-unsaturated carbonyl compounds with high regio- and chemoselectivity (>97/3) in low catalyst loading (1-5 mol %). The alkyl-substituted trimethylsilylvinyl epoxides gave beta,gamma-unsaturated ketone, but aryl-substituted vinylepoxides gave the aldehydes instead.     

2型糖尿病患者血清钙镁与甲状腺激素含量变化及临床意义

为了监测 2型糖尿病人血清钙、镁和甲状腺激素含量 ,分析其临床意义及相关性 ,应用放射免疫分析法测定了 1 1 5例 2型糖尿病及 1 5 0例健康人血清甲状腺激素含量。同时用美国杜邦RXL自动生化仪测定了其血清钙、镁含量。结果表明 ,在 2型糖尿病伴有明显并发症者血镁、FT3水平明显降低 (P <0 0 5 ) ,钙镁两种元素与甲状腺激素水平无明显相关性。 2型糖尿病患者适当补镁对预防其并发症是有益的 ,测定FT3 等可作为判断 2型糖尿病严重程度和估计预后的参考指标。     

Calculation of avoided crossings for highly excited Stark states of Rb

Using the method of diagonalization, in which zero-field wavefunctions from a potential model are chosen as a basis, we calculate positions and widths of anticrossings for highly excited Stark states of Rb with principal quantum number n up to 49. We obtain the theoretical positions and widths in good agreement with available experimental values, and we present scaling laws of the field positions and widths of anticrossings that can be used to provide information for future experiments.     

Dye-sensitized solar cells based on composite solid polymer electrolytes

The ionic conductivity of polymer electrolytes and their interfacial contact with dye-attached TiO2 particles were enhanced markedly by the addition of amorphous oligomer into polymer electrolytes, resulting in very high overall energy conversion efficiency.     

An addition to the oxoacid family: H2B12(OH)12

The acid H(2)B(12)(OH)(12) can be isolated as a crystalline solid by protonation of the hydroxylated borane anion, B(12)(OH)(12)(2)(-). This acidic compound has low solubility in water, conducts protons in the solid state, and has thermal stability to a temperature of 400 degrees C. The conductivity mechanism is a Grotthuss mechanism with a low activation enthalpy (9-13 kcal/mol). This new acid represents an addition to the class of oxoacids, of which sulfuric and phosphoric acid are the most prominent examples.     

Cyclization reactions of N-acryloyl-2-aminobenzaldehyde derivatives: formal total synthesis of martinellic acid

N-Alkyl acryloylamides derived from o-aminobenzaldehyde derivatives react with N-alkyl glycine derivatives to provide cis-fused pyrrole[3,2-c]quinolones in moderate yield and high diastereoselectivity. These same substrates engage in a tandem Michael-Mannich pathway on treatment with a secondary amine, providing corresponding quinolone derivatives. The elaboration of a pyrroloquinolone derivative via addition of an in situ generated functionalized copper acetylide to an in situ generated iminium ion provided the C2-substituted derivative. Global deprotection and reduction of the alkyne afford the tricyclic triamine core (as the HCl salt) found in martinellic acid.