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961.
自组装超分子膜修饰电极的研制及分析应用 总被引:4,自引:0,他引:4
阐述了自组装超分子膜修饰电极的发展概况及超分子体系形成的理论基础,并对自组装超分子膜修饰电极的特点、电化学行为、功能膜的制备和表征方法以及它在电催化、生物传感器、离子选择性电极等方面的应用进行了综述。 相似文献
962.
963.
Synthesis,Structure and Thermal Property of a Cobalt Supramolecular Complex Containing N-[(4-Carboxyphenyl)-sulfonyl]glycine 总被引:1,自引:1,他引:0
Utilizing N-[(4-carboxyphenyl)-sulfonyl]glycine (abbreviated as cbsglyH3),a new cobalt complex [Co(cbsglyH)(bipy)2]3H2O (bipy = 2,2'-bipyridine) has been synthesized under mild conditions and characterized by IR,elemental analysis,thermogravimetric analysis and X-ray diffraction analysis. It crystallizes in the monoclinic system,space group C2/c with a = 34.978(3),b = 12.0437(11),c = 20.0041(19) ,β = 122.2990(10)°,V = 7123.0(11) 3,Z = 8,C29H28CoN5O9S,Mr = 681.55,μ = 0.593 mm-1,Dc = 1.271 Kg/m3,F(000) = 2816,the final R = 0.0434 and wR = 0.1351. The title complex is a monomeric compound which is further assembled by intermolecular hydrogen bonds into a 3-D supramolecular network. Thermogravimetric analysis illustrates that this complex begins decomposing at 100 ℃ and decompounding completely at 560 ℃. 相似文献
964.
965.
烙印分子刚性对分子烙印手性固定手性拆分能力的影响 总被引:3,自引:3,他引:0
采用丙烯酰胺+2-乙烯基吡啶复合功能单体烙印了刚性较小的苯甲氧羰基-L-丝氨酸、苯甲氧羰基-L-丙氨酸和具有一定刚性的苯甲氧羰基-L-脯氨酸,发现丙烯酰胺+2-乙烯基吡啶体系对于分子刚性较小的分子也具有很好的烙印效果,表明不是烙印分子的刚性而是带有的与功能单体作用的化学功能基团才是实现分子烙印的关键。 相似文献
966.
967.
Yu-Yu DAI Wei-Jun LI Shuan-Ma YAN Shi-Zhao WANG Yue YU Mi OUYANG Li-Tao CHEN Cheng ZHANG 《物理化学学报》2017,33(11):2268-2276
A series of multi-branched dithienylpyrrole (SNS) monomers with rigid phenyl (PhSNS) and biphenyl rings (BPhSNS) as bridges were designed and synthesized, and were fabricated to form cross-linked polymers (pPhSNS, pBPhSNS) by electrochemical polymerization. Cyclic voltammetry (CV) results showed that PhSNS and BPhSNS exhibited similar oxidative properties except for one new higher-potential oxidative peak appearing in the curves of PhSNS. Theoretical calculations indicated that it should be attributed to the different steric configuration between the two dithienylpyrrole (SNS) units in PhSNS. One SNS unit possessed a larger twist angle (40.2°) between thiophene and pyrrole rings than the other one (21.2°), which indicated that PhSNS possessed a relatively larger energy gap (~0.4 eV) between HOMO-1 and HOMO than BPhSNS, for which HOMO and HOMO-1 levels were of almost the same energy. However, both PhSNS and BPhSNS showed similar onset oxidation potentials. The CV curves of pPhSNS and pBPhSNS showed that they presented similar oxidative properties, which enabled their corresponding electrochemical polymers to exhibit similar electrochromic properties. The UV-vis spectra of the corresponding polymers showed that both pPhSNS and pBPhSNS possessed similar optical absorption and similar multicolor switching between yellow (-0.8 V), greyish-green (0.9 V) and gray (1.1 V) colors. Besides, pPhSNS and pBPhSNS showed fast switching times of 0.57 s and 0.93 s at 1100 nm, respectively and reasonable contrasts of 46% and 31% at 1100 nm, respectively. These investigations may help understand the relationship between structural configuration and the electrochemistry/electrochromic properties for polymer electrochromic (PEC) materials research. 相似文献
968.
Pan Xiao Jun Wang Rong Yang Fu-Jiu Ke Meng-Fen Xia Yi-Long Bai 《Acta Mechanica Sinica》2013,29(5):676-681
Since rate effect of materials plays a key role in impact engineering, the microscopic mechanism of rate effect is investigated at molecular level in this paper. The results show that rate effect on the strength of atomic system is closely related to the coupled evolution of atomic motions and potential landscapes. Accordingly, it becomes possible to develop a new algorithm of molecular simulation, which could properly and efficiently demonstrate strain rate effect under a wide range of loading rates and unveil the mecha- nisms underlying the strain rate effects. 相似文献
969.
970.
运用原子力显微镜研究了十八烷基三氯硅烷在玻璃表面自组装形成单分子膜的过程.通过对样品表面的显微图像、表面平均粗糙度及前进接触角的测量分析,揭示了自组装单分子膜在玻璃表面的生长规律,并探索反应初期玻璃表面的吸附特点. 相似文献