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91.
LIU Ming-fei HU Yong-xing JIANG Yin-zhu GAO Jian-feng WANG Yan-yan MENG Guang-yao 《高等学校化学研究》2007,23(3):258-262
Praseodymium β-diketone chelate, Pr(DPM)3 [DPM=2,2,6,6-tetramethyl-3,5-heptanedionato], was successfully synthesized from the inorganic salt praseodymium chloride and HDPM(2,2,6,6-tetramethyl-3,5-heptane-dione) in an ethanol/aqueous solution followed distillation at low pressure and recrystallization from toluene. The physical and thermal properties of the chelate, including volatility, stability, and thermal decomposition, were investigated by elemental analyses, 1H NMR spectroscopy, XRD, TG/DTG/DTA analysis, infrared spectroscopy, and mass spectroscopy. The chelate with high purity prepared by thes of this study also shows sufficient volatility and stability in inert gases, which could be used as the precursor for metal-organic chemical vapor deposition(MOCVD). 相似文献
92.
Gu He Li Guo 《中国化学快报》2007,18(12):1505-1508
A convenient synthesis and theoretical study of five CCK-functional dendrimers is described.The dendritic cores were linked with the CCK(Trp-Met-Asp(OBn)-PheNH2) fragment by forming amide bonds to give five target molecules.The structures of CCK-functional dendrimers were characterized by NMR,MS spectrum and predicted using molecular mechanics and PM3 semi- empirical molecular orbital theory. 相似文献
93.
Xin Huang Jun Li Jian Hua Shen Jun Hua Chen 《中国化学快报》2007,18(12):1515-1517
Two new compounds,lethaclado acid A(1) and B(2),were isolated from the acetone extract of Lethariella cladonioides.Their structures were elucidated on the basis of 1D and 2D NMR as well as ESI-MS spectral data. 相似文献
94.
The preparation of functionalized single walled carbon nanotubes as high efficiency DNA carriers 总被引:1,自引:0,他引:1
Xiao Ying Yang Zun Feng Liu Jie Mao Shu Jing Wang Yan FengMa Yong Sheng Chen 《中国化学快报》2007,18(12):1551-1553
The positively charged single walled carbon nanotubes (SWNTs~ ) were prepared by conjugating with-CONH-C_6H_(12)-NH_3~ . The double strand DNA(dsDNA) chains were loaded onto SWNTs~ via the electrostatic interactions.SWNTs~ shows improved loading efficiency (353.5μg/mg) toward dsDNA compared with that of charged free single walled carbon nanotubes (SWNTs) (82.9μg/mg). 相似文献
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新型电活性聚(2,2'-二氨基苯氧基二硫化物)的电化学合成 总被引:1,自引:0,他引:1
在Pt电极上,LiClO4和不同酸的乙腈/四氢呋喃溶液中,通过动电位连续扫描法合成了新型电活性聚(2,2'-二氨基苯氧基二硫化物)(PDAPD),研究了电解质LiClO4及不同酸(HCl、CF3COOH、CCl3COOH、CH3COOH)的浓度对合成产物的影响,实验结果表明:浓度为0.1mol/L的LiClO4及浓度在0.05-0.5mol/L之间的HCl是获得高电活性的聚合物导电膜的最佳实验条件。 相似文献
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The deprotection of 1,3-dibenzyl-5-(N,N-dimethylamino)-6-phenyl-ethyluracil I was investigated. A practical, regioselective N3 deprotection of compound I was performed with excellent yield using cyclohexene as a hydrogen donor. 相似文献
100.
Surface-enhanced Raman scattering(SERS)-active gold nanoparticles(AuNPs) films were prepared with a one-step electrochemical method. The orthogonal design was used to investigate the experimental conditions influencing the morphologies and the SERS activity of the AuNPs. A condition was found to obtain the optimal SERS activity. The SEM study reveals that the AuNPs films were composed of closely packed AuNPs. The Finite Difference Time Domain(FDTD) simulation result indicates that the coupling between particles plays an important role in the enhancement SERS of AuNPs. 相似文献