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91.
Jian Zhi SUN Xiao Chuan DENG Shu Bin WEI Fa Qiang LI Pei Hua MA 《中国化学快报》2005,16(10):1401-1404
A new kind of adsorbent Li(1+x)AlxTi(2-x)(PO4)3 was synthesized by solid state reaction method. The influence of the content of doping aluminum on the adsorbent Li(1+x)AlxTi(2-x)(PO4)3 was investigated by XRD, while the morphology of powders was observed by SEM. The investigation of the adsorption properties showed that the adsorbent can selectively adsorb sodium with the adsorption capacity of 11.76 mg/g. The optimum conditions of adsorption are at pH 10.0-11.0 in LiCl solution. 相似文献
92.
Surface composition and property of film prepared with aqueous dispersion of polyurethaneurea-acrylate including fluorinated block copolymer 总被引:1,自引:0,他引:1
The aqueous dispersion of polyurethaneurea-acrylate (PUA) including small amount of fluorinated block copolymers containing carboxyl groups (PATF), which can be dissolved in water, was used to make films and the surface properties of these films were examined. The experimental data show that the modified PUA film exhibits a hydrophobic surface property, although the original surface of PUA film is hydrophilic. The surface composition of the modified PUA film was measured by ATR and XPS. The results indicate that there is a concentration gradient of the fluorine groups along the lines of thickness of the modified film and towards the outmost surface layer, resulting from the migration of fluorinated blocks to the air side surface of the modified PUA film during the film formation process. However, the PUA film can not be modified effectively by adding the sodium salt of PATF, since the urethane groups in the system are easy to occupy on the surface of the film. 相似文献
93.
This work describes a structure and kinetic stability study of some complexes with the general formula MN, where M are the alkaline earth metal atoms, Be, Mg, Ca, Sr, and Ba. A complex (A) with two points of attachment to the N5 ring is the most energetically favored for all metals considered here. Except for Be, structure (B) containing a mono‐coordinated metal atom is a transition state corresponding to the metal atom transfer around the N5 ring. Pyramidal structure (C) is kinetically unstable with the low isomerization barrier height, ranging from 0.9 to 6.7 kcal/mol. The dissociation barrier heights for the lowest energy isomers (A) are predicted to be 1.2–18.7 kcal/mol (Be to Ba), indicating that kinetic stability increases from lighter to heavier metal atoms. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004 相似文献
94.
Facile synthesis of 6(E)-geranylgeraniol-19-oic acid 1,a naturally occurring alicyclic diterpene acid, by a Horner-Wadsworth-Emmons olefination of two readily available fragments 2 and 3,is described. 相似文献
95.
Yuming Dong Yuqiang Ding Weifu Dong Cheng Yang Xuefeng Liu Ye Fan Jing Wang Qingwei Pan 《大学化学》1986,35(10):71-76
Based on the development prospect of cosmetics industry, the advantage of light industry characteristic and the foundation of applied chemistry in Jiangnan University, a systematic upgrading of applied chemistry was carried out through "emerging engineering education (3E)" project "upgrade and practice of chemistry-related majors of local and/or trade university responding to the social developments" supported by the Ministry of Education. On the basis of investigation and analysis, the orientation and training goal of applied chemistry were updated first, and then the curriculum system was determined and the curriculum construction is strengthened, so as to achieve more distinctive characteristics, more solid foundation and more comprehensive quality. In view of the new requirements of the 3E for talent training, some practices have been formed in the aspects of multi-disciplinary integration, multi-angle coordination and close integration to industry. Contributing the development of cosmetics industry and seizing the commanding point of science and technology from the perspective of talent training, will play a unique role in human social progress. 相似文献
96.
Reaction of laser-ablated Zr with CH(4) ((13)CH(4), CD(4), and CH(2)D(2)) in excess neon during condensation at 5 K forms CH(2)=ZrH(2), the simplest alkylidene hydride complex, which is identified by infrared absorptions at 1581.0, 1546.2, 757.0, and 634.5 cm(-)(1). Density functional theory electronic structure calculations using a large basis set with polarization functions predict a C(1) symmetry structure with agostic C-H- - -Zr bonding and distance of 2.300 A. Identification of the agostic CH(2)=ZrH(2) methylidene complex is confirmed by an excellent match of calculated and observed isotopic frequencies particularly for the four unique CHD=ZrHD isotopic modifications. The analogous reactions in excess argon give two persistent photoreversible matrix configurations for CH(2)=ZrH(2). Finally, methane activation by CH(2)=ZrH(2) gives the new (CH(3))(2)ZrH(2) molecule. 相似文献
97.
HongWU ZhongJIANG SongWeiXU ShuFangHUANG 《中国化学快报》2003,14(4):423-425
CO2 is converted to nethanol through an enzymatic approach using formate dehydrogenase(FateDH),formaldehyde dehydrogenase(FaldDH)and alcohol dehydrogenase(ADH)coencapsulated in silica gel prepared by modified sol-gel process as catalysts,TEOS as precursor,NADH as an electron donor.The highest yield of methanol was up to 92.1% under 37℃,pH7.0 and 0.3Mpa. 相似文献
98.
Shu Jun WANG Wen Yuan GAO Jing Lin YU Pei Gen XIAO 《中国化学快报》2006,17(9):1255-1258
Dioscoreae (Chinese name Shanyao), the rhizome of various species of genus Dioscorea opposita Thunb.(Dioscoreaceae), has been used as an important invigorant in traditional Chinese medicine (TCM) for many years1. Starch, the most abundant carbohydrate in … 相似文献
99.
许多三唑类化合物具有优良的杀菌和植物生长调节活性 ,如三唑酮、三唑醇、烯效唑、烯唑醇等 ,对常见真菌病害具有很好的防治效果 ,并具有增产、抗倒和生长调节作用 ,已成为重要的杀菌剂类型 [1] .为筛选新型高活性三唑类杀菌剂和探讨其活性与结构间的关系 ,我们利用生物等排体理论以常规三唑类杀菌剂三唑酮为先导物设计合成了 1 6个含芳硫基的新三唑类化合物 ,其合成路线如下 :RCCH2 BrO+HNNNB NRCCH2O NNHAC-Na ACBr2NRCCHOBrNN(1 ) (2 ) (3 )3 +SH R′B NRCCHOS R′NN (4 )RCCH2 CH2 NMe2 .HClO+HNNNH2 O… 相似文献
100.
微波在分析化学及有机合成中的应用 总被引:13,自引:0,他引:13
综述了近10年来微波技术在分析化学和有机合成中的应用,着重介绍了微波消解在分析化学和微波辐射在有机合成反应中的应用进展。 相似文献