(TiNi)_x(x=2~4)团簇结构和电子结构

从团簇角度对TiNi形状记忆合金进行了量子化学从头算研究。设计并优化了等原子比(TiNi)x(x=2~4)簇的多种可能几何结构,并对较稳定构型进行电子结构的分析。结果表明,等原子比的(TiNi)n团簇以TiNi成键为主要分子骨架,小团簇有较多能量接近的异构体,TiTi成键对能量降低有较大贡献。     

表面包覆改性对纳米CeO2分散性的影响

了改善纳米CeO2在Zn-Al类共晶合金中的分散性,采用超声液相包覆法对纳米CeO2进行表面活性剂表面包覆改性,并用AES测定了包覆层的厚度,用TEM研究了CeO2的团聚状况,用TGA分析了有机物包覆层的炭化温度范围,最后用FE-SEM观察了CeO2在复合材料中的分散情况。结果表明,包覆在纳米CeO2表面的厚度约为20 nm的表面活性剂层提高了微粒的分散性,而且该包覆层在495℃时已经炭化。热力学计算的结果也表明,炭化层能与氧化膜反应,该反应提高了CeO2与基体间的润湿性,并使其均匀分布在基体合金中。     

[α-(2-氧代烷基)-α-(取代苯胺基)甲基苯基]-β-D-吡喃阿洛糖苷的合成及镇静活性研究

以豆腐果苷为原料, 通过Mannich反应与取代苯胺和脂肪酮共合成了七个豆腐果苷衍生物, 均未见文献报道. 其结构经¹H NMR, IR, MS和HRMS确认, 并进行了药理活性筛选. 结果表明, 部分化合物均具有良好的镇静活性. 其中, 化合物2a (200 mg/kg), 2b (200 or 100 mg/kg)和2e (200 mg/kg)与豆腐果苷相比较, 具有更强的疗效.     

钯催化α-炔醇立体专一合成α-（Z）-氯亚甲基-β-内酯

首次在一氧化碳存在下，以仲丁醇和苯为混合反应溶剂，氯化钯和氯化铜为催 化体系催化α-炔醇羰基化，立体专一合成α-（Z）-氯亚甲基-β-内酯环。     

Preparation and characterization of C16 monolithic columns for capillary electrochromatography

A series of methacrylamide-based C16 monolithic columns were prepared and characterized to determine how their porous structural properties and chromatographic behavior are affected by the percentages of functional monomer, base monomer, and cross-linker in the polymerization solution. Baseline separation of 6 neutral compounds can be readily obtained in an optimized column. Furthermore, the effects of organic additive in the mobile phase, operating voltages, and temperature on retention behaviors and separation efficiencies were also studied. The separation mechanism is also discussed. High column efficiency and good reproducibility indicate that the monolithic columns hold considerable promise.     

Characterization of low molecular weight components of [(ViMe2SiO1/2)x(PhSiO3/2)y(SiO4/2)z], [(ViMe2SiO1/2)x(SiO4/2)y], and [(SiO4/2)x(HO1/2)y(tBuO1/2)z] silsesquioxanes by electrospray ionization fourier transform mass spectrometry (ESI-FTMS)

This paper describes the characterization of low molecular weight components of four materials using electrospray ionization Fourier transform mass spectrometry (ESI-FTMS). The materials in the current study are [(ViMe₂SiO_1/2)_x(PhSiO_3/2)_y(SiO_4/2)_z] (MTQ), [(ViMe₂SiO_1/2)_x(SiO_4/2)_y] (MQ), and [(SiO_4/2)_x(HO_1/2)_y(^tBuO_1/2)_z] (Q) silsesquioxanes. Accurate mass measurements coupled with knowledge of resin chemistry afforded siloxane composition determination that was used to propose specific structures for the oligomers. Branched or linear (T_nQ_mM_n+2m+2), and monocyclic (T_nQ_mM_n+2m) structures are predominant structures for the low molecular weight species in MTQ. For MQ and Q, more condensed structures, such as partially opened cage structures (Q_mM_2m?6 and Q_mM_2m?8), were identified. The differences between MQ, Q, and MTQ are likely attributed to differences in intrinsic structure and reactivity of T and Q building blocks. The structural information obtained for these oligomeric species will ultimately provide a better understanding of new resin materials and their associated physical properties.     

超临界二氧化碳在高分子合成及加工领域的应用

重点概述了近年来超临界二氧化碳作为环境友好介质在高分子合成与加工方面研究的新进展,具体介绍了在超临界二氧化碳中丙烯酸的合成及疏水改性方面所做的工作,并在此基础上,展望超临界二氧化碳作为高分子合成介质的前景。     

三维聚合物双(三丁基锡)戊二酸酯的合成及晶体结构研究

用三丁基氯化锡与戊二羧酸二钠以2:1摩尔比反应,合成了双（三丁基锡）戊二羧酸酯,并用元素分析、红外光谱、核磁共振氢谱及X-射线单晶衍射进行了表征和结构测定。X-射线单晶衍射法测定表明,化合物属单斜晶系,空间群为Cc,晶胞参数:a=13.984（3）,b=16.164（3）,c=16.894（3）A,β=107.457（3）°,V=3642.9（11）A3,Z=4,C29H60O4Sn2,Dc=1.251g/cm3,μ=1.394 mm-1,R=0.0500,wR=0.0874,F（000）=1416。晶体结构中存在2种化学环境不同的三角双锥构型的锡原子,由于配体中2个羧基在不同方向的交联作用,使化合物呈现三维立体骨架结构,并且在骨架结构中存在沿a、b、c轴3个方向伸展的规则的大环直孔道。     

Circularly Polarized Absorption Property of Tetra-4[4''''-(2-methylbutoxy)benzoyloxy]phenyl Porphyrin by Introducing Optical Pendant Groups

Circularly polarized luminescent(CPL) materials possess special dissymmetric optical property, i.e. luminescent light having different intensities for left (L) and right(R) circularly polarized components. Recently, these materials have been applied in colour-image projection, stereoscopic displays and light-emitting diodes(LEDS)1-7. We have synthesized a new porphyrin derivative, tetra-4[4'-(2-methylbutoxy)benzoyloxy] phenyl porphyrin [T(MBBP)P], by introducing a chiral group, which p…     

取代邻苯二腈的合成

在室温条件下合成了一系列芳氧基邻苯二腈化合物,应用无素分析、1HNMR、IR确定了它们的结构,讨论了不同取代基对反应的影响.结果表明,酚的芳环上有推电子基时反应容易进行;酚的芳环上有拉电子基时反应慢或不反应.