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951.
A carbon paste electrode modified with electropolymerized fills of isonicotinic acid was developed.The modified electrode shows excellent electrocatalytic activity toward the oxidation of both dopamine(DA)and epinephrine(EP).Separation of the reduction peak potentials for dopamine and epinephrine was about 357 mV in pH 5.3 phosphate buffer solution(PBS)and the character was used for the detection DA and EP simultaneously.The peak currents increase linearly with DA and EP concentration over the range of 8.0×10-5 to 7.0×10-4 mol/L and 5.0×10-6 to 1.0×10-4 mol/L with detection limits of 2 × 10-5 and 1×10-6 mol/L,respectively.The interference studies showed that the modified electrode exhibits excellent selectivity in the presence of large excess of ascorbic acid(AA). 相似文献
952.
An modified laminar crystal sodium silicate(Al-SKS-6)was synthesized by spray drying and high temperature crystallization using sodium silicate as silicon source,Al atom as inorganic source and hexadecyltrimethy ammomum bromide(CTMAB)as the structure template.The hydrothermal stability of product was at least 1 h.The synthesized material was characterized by XRD and SEM.The results indicated that shape and intensity of XRD diffraction peak at 20 took changes.but raw material δ phase crystal form kept unchanged.and assured high Ca2+ and Mg2+ binding capacity of the products.The Ca2+ and Mg2+ binding capacity of product is up to 380 mg Ca/g and 410mg Mg/g respectively.It was found that the hole of product became smaller and appeared rod structure based on SEM. The hydrothermal stability was increased due to the pillaring of A1 atom. 相似文献
953.
In this article,a novel strong interaction by forming complex between bovine serum albumin(BSA) and copper ion was utilized for the preparation of molecular imprinted hydrogel in aqueous solution.Results show that the inclusion of copper ion in preparation can bridge the template BSA and functional monomers together and improve the imprinting effect compared to the polymer made without copper ion added.High selectivity factor and large adsorption capacity are also observed for the obtained BSA-imprinted ... 相似文献
954.
Kuo-xi Xu Zhen Qiu Jin-Jin Zhao Jin Zhao Chao-jie Wang 《Tetrahedron: Asymmetry》2009,20(14):1690-1696
The derivatives of BINOL, (S)-1 and (R)-1, and their analogues have been prepared and the structures of these compounds have been characterized by IR, MS, 1H, and 13C NMR spectroscopy and elemental analysis. The enantioselective recognition of these receptors has been studied by fluorescence titration and 1H NMR spectroscopy. The receptors exhibited different chiral recognition abilities toward some enantiomers of chiral materials and formed 1:1 complexes between host and guest. Receptor (S)-1 or (R)-1 exhibits excellent enantioselective fluorescent recognition abilities toward amino acid derivatives. 相似文献
955.
Lu Liu Ming Ge Huajie Liu Changsheng Guo Yuqiu Wang Zhen Zhou 《Colloids and surfaces. A, Physicochemical and engineering aspects》2009,348(1-3):124-129
The synthesis of ZnO with different morphologies (hexagonal prisms, nanosheets, microspheres and quasi-flowers) was realized through a solvothermal method. During the synthetic procedure, the decomposition of hexamethylenetetramine at the temperature ≥100 °C provided (OH)−1 ions at the rate of good distribution, and sodium dodecyl sulfate was used as templates. By adjusting the basicity in the synthetic system, ZnO nanosheets, or microspheres with nanosheet assemblies were obtained. Adjusting the concentration of surfactant, ZnO hexagonal crystals were formed; by adjusting the synthetic temperature, ZnO quasi-flowers with some nanosheet assemblies were produced. Based on experimental observation and analysis, the forming mechanism was discussed. 相似文献
956.
具有多级孔结构的NH4-β沸石的直接合成及其性能 总被引:1,自引:0,他引:1
以非离子表面活性剂壬基酚聚氧乙烯醚(Tx-15)为模板,设计氟化铵作为矿化剂.在近中性条件下直接合成了具有微孔-介孔复合孔道的铵型β沸石.合成样品采用粉末X射线衍射(PXRD),高分辨扫描电子显微镜(SEM),微分热重(DTG)以及氨程序升温脱附(NH3-TPD)等手段进行了表征.结果表明,氟离子及非离子表面活性剂的加入对沸石的孔结构、酸性质均起到了一定的调变作用.该沸石具有发达的呈梯级分布的多级孔结构,孔容高达0.67 cm3·g-1,且具有较强的Bronsted酸和适度分布的Lewis酸,大大改善了反应物和产物分子的扩散和反应性能.在混合C4烃的催化裂解反应中,该沸石与传统方法合成的β沸石相比,其转化率提高了约15%,烯烃(乙烯和丙烯)产率提高了近10%,芳烃(苯和甲苯)产率提高了3%. 相似文献
957.
Zhen‐Yi Jiang Yu‐Qing Hou Kuo‐Hsing Lee San‐Yan Chu 《International journal of quantum chemistry》2009,109(4):861-869
The structures and relative stability of the maximum‐spin n+1Aun and nAu (n = 2–8) clusters have been determined by density‐functional theory. The structure optimizations and vibrational frequency analysis are performed with the gradient‐corrections of Perdew along with his 1981 local correlation functional, combined with SBKJC effective core potential, augmented in the valence basis set by a set of f functions. We predicted the existence of a number of previously unknown isomers. The energetic and electronic properties of the small high‐spin gold clusters are strongly dependent on sizes. The high‐spin clusters tend to holding three‐dimensional geometry rather than planar form preferred in low‐spin situations. In whole high‐spin Aun (n = 2–8) neutral and cationic species, 5Au4, 2Au, and 4Au are predicted to be of high stability, which can be explained by valence bond theory. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 相似文献
958.
Hydrosilylation has been carried out between Si-H terminated polydimethylsiloxanes with narrow molecular weight distribution and protected 3-allyloxy-1,2-propanediol, and after subsequently alcoholyzed, α-{3-[(2,3-dihydroxy)propoxy]propyl}-ω-butyl-polydimethylsiloxanes with varying number of ((Si(CH3)2-O) unit were obtained. At each step, the produced compounds were carefully characterized. The results showed that each step was successfully carried out and target products were achieved. 相似文献
959.
Long Yi Heyang Li Lu Sun Liangliang Liu Caihong Zhang Zhen Xi Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(22):4034-4037
Fast detection of cellular thiols in aqueous medium was achieved using a newly developed fluorescence probe (see picture). Based on this probe, a high‐throughput fluorescence assay for glutathione reductase was developed.
960.
Zhen‐Zhou Cao Zheng‐Rong Wei Dr. Lin‐Qiang Hua Chang‐Jin Hu Dr. Song Zhang Dr. Bing Zhang Prof. 《Chemphyschem》2009,10(8):1299-1304
Photodissociation dynamics and rotational wave packet coherences of o‐bromofluorobenzene are studied by femtosecond time‐resolved photoelectron imaging (see figure). The decay of different photoelectron rings shows the population decay of states from which the lifetimes of different states are determined. The variation of photoelectron angular distributions reflects the evolution of rotational coherences.