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951.
Qing‐Xiang Liu Feng‐Bo Xu Qing‐Shan Li Xian‐Shun Zeng Xue‐Bing Leng Zheng‐Zhi Zhang 《中国化学》2002,20(9):878-883
Dinuclear silver (I) six‐membered ring complex [Ag2 (bta)2 ‐(hmbta)2] (ClO4)2 (3) has been synthesized by the reaction of benzotriazole (bta) (1) and 1‐hydroxymethyl benzotriazole (hmbta) (2) with Ag (CH3CN)4ClO4. The structures of compound 2 and Complex 3 have been studied by single crystal X‐ray diffraction analysis. The change of luminescent intensity of 1, 2 and 3 was reported. Compound 2 crystallizes in the monoclinic system with space group P2 (1)/c, a = 0.7655 (10) nm, b = 1.0126 (14) nm, c =0.9502 (13) nm, β = 95.07 (2)°, V = 0.7337 (17) nm3 and Z = 4. Complex 3 crystallizes in the triclinic system with space group P1, a = 0.73611 (18) nm, b = 0.9152 (2) nm, c = 1.2277 (3) nm, β = 87.170 (5)°, V = 0.8221 (3) nm3 and Z = 1. The main structural feature of complex 3 is a symmetric dinuclear six‐membered ring formed by two silver (I) atoms and four N‐atoms from two benzotriazoles. The second structural feature of complex 3 is the τ‐τ stacking interaction between two adjacent molecular planes, which forms the two‐dimentional layer structure. Besides, compared with 2, the luminescent intensity of complex 3 shows a remarkable enhancement. 相似文献
952.
A protein array for cell detection was fabricated by spotting different antibodies on modified glass slides. Glass slides were modified to allow antibodies to be immobilized on it and to selectively bind antigens. Antibodies were specially selected with the cells to be detected as targets, which permitted target cells in samples to bind specifically to the array with little nonspecific binding. Results can be obtained by directly putting the samples onto the array for 1 h or a little longer to let the cells specifically interact with the antibodies. After washing the unbound samples away, images were observed with a microscope and captured with a CCD camera. The assessment of antibody-cell binding was evaluated by capturing red blood cells (RBCs) in human blood with blood group antibodies (anti-A and anti-B). Blood group antibodies were spotted on the modified glass slide and kept at 4<.deg> degrees C overnight for immobilization. Human blood samples diluted to different concentrations were used to examine the sensitivity and specificity of the method. 相似文献
953.
Extraction and characterization of adenovirus 总被引:5,自引:0,他引:5
Mirza UA Liu YH Tang JT Porter F Bondoc L Chen G Pramanik BN Nagabhushan TL 《Journal of the American Society for Mass Spectrometry》2000,11(4):356-361
A new methodology for the extraction and characterization of proteins from Coomassie-stained sodium dodecylsulfate polyacrylamide gel electrophoresis using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been described. The utility of this methodology was demonstrated in the characterization of adenovirus proteins. The key steps in the extraction and destaining process involve washing the excised band with a combination of solvents that include 10% acetic acid, acetonitrile, methanol, and formic acid:water:isopropanol mixture. By using this procedure, we determined adenovirus proteins with molecular weights ranging from 10,000 to 110,000 Da by MALDI-MS, obtaining a detection limit of approximately 6 pmol. Parallel experiments were successfully carried out to analyze adenovirus proteins from Cu-stained gels. It was observed that increase in laser intensity resulted in significant improvements in the quality of MALDI mass spectra for the analysis of inefficiently destained proteins from Cu-stained gels. 相似文献
954.
Mingzhu Liu Rongshi Cheng Jingjia Wu Cheng Ma 《Journal of polymer science. Part A, Polymer chemistry》1993,31(13):3181-3186
A study was made of the ceric ammonium nitrate (CAN) initiated graft copolymerization of methyl acrylate (MA) onto potato starch. The variables affecting the graft were investigated. The optimums have been obtained; they are the concentrations of MA, CAN, and nitric acid (HNO3) (1.08, 5.0 × 10?3, and 0.081 mol/L, respectively). The reaction temperature is ca. 50°C and the reaction time is 2 h. The molecular weight of grafted poly(methylacrylate) has been determined. On the basis of experimental results, the mechanism of grafting has been explored, a new kinetic equation of the graft copolymerization is established: Rp = Kkd [STOH] [Ce4+] + Kkpkd/kt[STOH][M], where K, kd, kp, and kt are constants. The equation fits the results of experiments. © 1993 John Wiley & Sons, Inc. 相似文献
955.
本文对“中间盐”复分解制碱法进行了研究。“中间盐”的加入不能使两个三盐共饱和点在干盐图上发生明显的移动,但能使三盐介稳平衡点的介稳期延长,从而使得用碳酸氢铵和食盐通过复分解制碱成为可能。 相似文献
956.
以乙基紫为活性物质的聚氯乙烯膜氰化亚金电极的研制和应用 总被引:3,自引:0,他引:3
以碱性染料为活性物质制备20余种不同组分PVC膜Au(CN)2^-电极,确定较佳膜组成为乙基紫0.99%,邻苯二甲酸二丁酯69.2%,PVC粉29.8%。该电极对Au(CN)2^-浓度在5.0×10^-7 ̄1.0×10^-2mol/L范围内接近能斯特响应;斜率为55.7mV(30℃)。稳定性与选择性较好。该电极制备简单,使用方便,已成功用于氰化镀金液中金的测定。 相似文献
957.
新型糠醛加氢制糠醇催化剂研究 总被引:8,自引:0,他引:8
新型糠醛加氢制糠醇催化剂研究林培滋,黄世煜,周焕文,赵彤彤,刘崇早,罗洪原,梁东白(中国科学院大连化学物理研究所,大连116023)关键词铜催化剂,糠醛,加氢,糠醇糠醇是重要的化工原料,糖醇树脂是耐酸、碱腐蚀的材料,在工业发达的国家中,铸造工业广泛采... 相似文献
958.
Yun‐Yu Liu Guang‐Shan Zhu Guo‐Zhen Fan Shi‐Lun Qiu 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):m159-m160
In the title compound, poly[μ5‐pyrazine‐2,3‐dicarboxylato‐cadmium(II)], [Cd(C6H2N2O4)]n or [Cd(pdc)]n, where pdc is the pyrazine‐2,3‐dicarboxylate anion, the CdII atom is six‐coordinated by five carboxylate O atoms and one N atom from five different pdc ligands in a distorted octahedral CdO5N coordination geometry. Two CdII atoms are bridged by carboxylate groups of the pdc ligands to create a dimeric unit. The dimeric units are further connected by the pdc ligands to generate an interesting two‐dimensional structure. 相似文献
959.
Denifl S Ptasińska S Sonnweber B Scheier P Liu D Hagelberg F Mack J Scott LT Märk TD 《The Journal of chemical physics》2005,123(10):104308
Electron attachment to the polyaromatic hydrocarbons coronene and corannulene is studied in the electron energy range of about 0-14 eV using a high-resolution crossed electron-neutral beam setup. The major anions observed are the parent anions peaking at about 0 eV with cross sections of 3.8 x 10(-20) and 1 x 10(-19) m(2), respectively. The only fragment anions formed in coronene and corannulene are the dehydrogenated coronene and corannulene anions. Other anions observed in the negative mass spectra at about 0 eV can be ascribed to impurities of the sample. High-level quantum-mechanical studies are carried out for the determination of electron affinities, hydrogen binding energies, and structures of both molecules. The behavior of coronene and corannulene upon electron attachment is compared with that of other polyaromatic hydrocarbons studied previously. 相似文献
960.
Xiongyu Wu Xiaohong Liu Guangce Jiang Yongcheng Lin Willy Chan L. L. P. Vrijmoed 《Chemistry of Natural Compounds》2005,41(1):27-29
A novel metabolite 1, named xyloketal G, was isolated from cultures of marine derived mangrove fungus Xylaria sp. 2508. Its structure was elucidated by analysis of spectroscopic data.__________Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 22–23, January–February, 2005. 相似文献