A ONE-STEP SURFACE MODIFICATION PROCEDURE TO PEG-GRAFTED NANO-TITANIA

PEG （Polyethylene Glycol）-grafted nano-titania has been obtained in a one-step procedure using hexamethylene diisocyanate as the coupling agent and dibutyltin dilaurate as the catalyst in toluene at 80℃ and characterized qualitatively by FTIR and quantitatively by elemental analysis and thermogravimetric analysis. A comparison of nano-titania with two other commonly used inorganic nanoparticles, nano-silica and nano-alumina, is made, revealing that reactivity order is nano- silica 〉 nano-alumina 〉 nano-titania in view of PEG grafting. Possible mechanism of PEG grafting is also discussed.     

C~4~0, C~4~0^+, Nb@C~4~0^+, NbC~3~9^+, Nb@C~4~0H~4^+的 量子化学研究

用量子化学从头计算方法研究了C~4~0,C~4~0^+,Nb@C~4~0^+,NbC~3~9^+,Nb@C~4~0H~4^+的几何构型、电子结构和C~2~8一样,C~4~0(T~d)基态也为^5A~2态,笼骨架上具有四个悬挂键。计算结果表明C~4~0和C~4~0^+比NbC~3~9^+和Nb@C~4~0^+稳定,与实验结果一致。     

一种新颖一维铅碘聚合物[(Pb_2I_5)(L-H~ )·2DMF]_n(L=Piperazine)的自组装合成和晶体结构(英文)

0IntroductionIncreasinginterestisfocusedonthestudyofmagnetic,electronicandoptoelectronicpropertiesoflow鄄dimensionalorganic鄄inorganichybridcompoun鄄ds[1~3].Studiesshowthatcomplexconsistingoforganicandinorganiccomponentshavegreatpotentialforthecreationoff…     

4－（2－氨基噻唑）－间苯二酚为柱前衍化剂液相色谱／电化学检测Fe、Co、Ni

４－（２－氨基噻唑）－间苯二酚为柱前衍化剂液相色谱／电化学检测Ｆｅ、Ｃｏ、Ｎｉ格日勒，李惠梅，李南强，汪尔康（中国科学院长春应用化学研究所电分析化学开放实验室，北京大学化学系，长春，１３００２２）关键词液相色谱，Ｆｅ，Ｃｏ，Ｎｉ，４－（２－氨基噻唑）...     

高聚物固体电解质聚氧化乙烯－溴化铜复阻抗谱及介电常数的静水压效应

采用分子量５００万的聚氧化乙烯和无水溴化铜，通过混溶蒸发法制备成高聚物固体电解质Ｐ（ＥＯ）ｎ－ＣｕＢｒ２薄膜，并在０．１～３００ＭＰａ范围不同的流体静水压下详细测量其复平面阻抗谱，分别得到在不同压力下离子电导率和介电常数与测量频率的关系．进一步解谱准确地求出Ｐ（ＥＯ）ｎ－ＣｕＢｒ２（ｎ＝１２、１６）薄膜离子电导率和介电常数的静水压效应，并结合Ｘ－光物相分析，根据离子迁移通道的物理图象和高聚物的极化机构进行了初步的讨论．添加２０％的增塑剂碳酸丙烯酯，较大改进了压力下的导电性．１２０～３００ＭＰａ的离子电导率提高一个数量级     

对环氧化反应具有高催化活性的钛硅介孔分子筛的制备

 使用短链二元羧酸（包括草酸、戊二酸、柠檬酸和酒石酸）为模板剂，采用溶胶－凝胶法合成了具有大比表面积，孔径在3～7nm的钛硅介孔分子筛．EDX和紫外可见漫反射光谱的研究结果表明，所合成的钛硅介孔分子筛中钛的分布均匀，钛物种以孤立态四面体构型为主．本方法所合成的钛硅介孔分子筛对环己烯环氧化反应具有很高的催化活性和选择性．     

羧酸直接酰胺化的一个新方法

N, N-二甲基取代酰胺可以方便地由脂肪族或芳香羧酸与四(二甲氨基)硅烷在无水溶剂中反应制得。     

聚（3—丁基噻吩）电导的热稳定性

研究了导电聚合物聚（３－丁基噻吩）（ＰＢＴ）在大气环境下的导电热稳定性。在室温至２２０℃范围内，测试电导率随时间及温度的变化。ＴＧＡ分析以及化学分析的结果表明：掺杂态的ＰＢＴ大约在１４０℃附近有一转化温度，低于或高于这一转化温度，电导率下降的决定因素各不相同。高于转化温度时，电导率下降的主要原因是反离子和高分子主链的解离，进而发生化学反应，影响了高分子主链的结构。ＸＰＳ测试结果表明：经热处理后的Ｐ     

Preparation and optical properties of Eu(III) complexes J-aggregate formed on the surface of silver nanoparticles

Ag colloidal nanoparticles coated with Eu(TTA)₃ · 2H₂O complexes were prepared, and it was found that Eu(TTA)₃ · 2H₂O complexes J-aggregate was formed on the surface of Ag nanoparticles according to a red shift (18.2 nm) in UV–Vis spectra. However, there had similar excitation wavelength, which was attributed to existence of Ag nanoparticles. Highly luminescent properties of Ag colloidal nanoparticles were observed, and it was believed to result from low energy transfer between Eu(III) complexes and Ag and the large electromagnetic field arising from the excitation of surface plasmon polariton of Ag nanoparticles.