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31.
本文利用表面光电压谱(Surface Photovohage spectroscopy,简称SPS)研究了ZnTPP对TiO_2粉末的光谱敏化,发现用ZnTPP修饰后的TiO_2(金红石和锐钛矿)粉末在可见区420、550和590nm附近有三个光伏响应带,它们分别对应于ZnTPP的Soret、Q(1,0)和Q(0,0)带。经过严格的实验和分析,证明这三个带是由ZnTPP对TiO_2的敏化光电压引起的,而不是ZnTPP自身的光伏响应。在敏化效果上,亚稳的锐钛矿优于金红石。同时,我们对这种光敏表面的光诱导电荷转移机制和SPS作为一种研究光谱敏化方法的可行性进行了讨论。 相似文献
32.
A. W. Flounders D. L. Brandon A. H. Bates 《Applied biochemistry and biotechnology》1995,50(3):265-284
Monoclonal antibodies specific for thiabendazole were immobilized to silicon, silicon dioxide, stoichiometric silicon nitride,
and silicon-rich silicon nitride surfaces. This work provides the foundation for the development of a homogeneous sensor system
for rapid detection and quantification of thiabendazole residues in produce and animal tissue. Immobilization was performed
via aqueous silanization of the substrate followed sequentially by treatment with glutaraldehyde and contact with antibody
solution in the presence of detergent. Surfaces were challenged with thiabendazole-horseradish peroxidase conjugate in an
ELISA format to estimate immobilized antibody load. A stable and reproducible surface loading of 2 x 1011 antibodies/cm2 was obtained only after surfaces received postimmobilization treatments to remove nonspecifically adsorbed antibody. No difference
in surface loading was noted when using 30% hydrogen peroxide rather than nitric acid for silanol activation. Little difference
was noted among the antibody loadings achieved on the various silicon substrates. Bound antigen-enzyme conjugate was eluted
with 0.1N acetic acid and reproducible surface activity was measured for up to four consecutive antigen challenges. Immobilized
antibody surfaces were stabilized with 2% sucrose, dehydrated at 37‡C and stored in vacuum or stored at 4‡C in phosphate buffered
saline containing 0.01% sodium azide without significant loss of activity. 相似文献
33.
环境中排放的重金属离子Cu!对水生和陆生生物有强的毒害性。饮用水中Cu!的浓度高于1.0mg·L-1时,将会导致人畜得血色沉着病和胃肠粘膜病[1]。Cu!无法进行生物降解,除去废水中Cu!的常见方法有离子交换、置换、化学沉淀等[2],然而这些方法需要消耗大量的化学试剂,成本高。近来,研 相似文献
34.
用溶胶-凝胶法以磷钼酸(MPA)的铜盐溶液水解钛酸四丁酯制备了CuPMo/TiO2催化剂,并用ICP,XRD,TG-DTA,IR,TPD-MS和微反技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化性能.结果表明:杂多钼酸盐与TiO2表面通过O2-桥发生键联.在623K下,杂多阴离子仍保持其原有的Keggin结构;CO2在Lewis酸位Cu(Ⅱ)和Lewis碱位Cu-O-Mo桥氧的协同作用下形成卧式吸附态Cu(Ⅱ)←O-(CO)←(O--Cu);丙烯以分子吸附态在催化剂上吸附;在空速1500h-1,压力1MPa和温度563K的反应条件下,丙烯的转化率为4.2%,甲基丙烯酸的选择性为96%. 相似文献
35.
36.
The gas phase reaction between CO2 and lanthanide atoms. A test of a model for the isokinetic effect
Summary Co3O4, NiCo2O4 and LaCo2O4catalysts were synthesizedby the citric acid-ligated method. These catalysts containing Co-oxide active components can largely
lower the temperature of soot combustion under tight contact conditions. Under the conditions of loose contact NiCo2O4 cannot promote soot combustion, but LaCo2O4 can effectively promote soot combustion because the nanometric perovskite-type catalyst LaCoO3produced in the LaCo2O4sample.</o:p> 相似文献
37.
《Surface and interface analysis : SIA》2005,37(8):683-688
Heating (100) silicon at high temperature (say, higher than 850 °C) in H2, cooling to 670–700 °C in the same ambient, and quenching to room temperature in N2 results in environmentally robust, terraced 1 × 1 (100) SiH2. Evidence for this conclusion is based on angle‐resolved x‐ray photoelectron spectroscopy, atomic force microscopy, infrared absorption spectroscopy in the attenuated total reflection mode, thermal programmed desorption, and reflection high‐energy electron diffraction. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
38.
39.
A. A. Korlyukov K. A. Lyssenko M. Yu. Antipin A. G. Shipov O. A. Zamyshlyaeva E. P. Kramarova Vad. V. Negrebetsky S. A. Pogozhikh Yu. E. Ovchinnikov Yu. I. Baukov 《Russian Chemical Bulletin》2004,53(9):1924-1931
The reaction of 4-(2-hydroxybenzoyl)-2,2,6,6-tetramethyl-2,6-disilamorpholine with BF3Et2O afforded (O-B)-chelate 4-[2-(difluoroboroxy)benzoyl]-2,2,6,6-tetramethyl-2,6-disilamorpholine. Treatment of the latter with BF3Et2O or SOCl2 gave rise to products of the disilamorpholine ring opening, viz., (O-B) chelate 2-(difluoroboroxy)-N,N-bis(dimethylfluorosilylmethyl)benzamide or 2-(difluoroboroxy)-N, N-bis(dimethylchlorosilylmethyl)benzamide, respectively. The structures of the compounds synthesized were confirmed by X-ray diffraction analysis and 1H, 13C, and 29Si NMR spectroscopy. High-precision X-ray diffraction study and quantum-chemical calculations demonstrated that the coordination OSi bond is absent in the two last-mentioned compounds.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1846–1853, September, 2004. 相似文献
40.
二氧化碳多相催化加氢的新进展 总被引:4,自引:0,他引:4
就近年来关于CO2活化、几个重要的CO2多相催化加氢反应及廉价氢的供给的研究进展进行综述。参考文献34篇。 相似文献