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991.
Magnetic nanoparticles-supported quaternary ammonium and phosphonium salts were prepared and evaluated as phase-transfer catalysts. Some of them exhibited good activities that were comparable to that of tetra-n-butylammonium iodide. The catalysts were readily separated using an external magnet and reusable without significant loss of their catalytic efficiency. 相似文献
992.
Machida M Sato K Ishibashi I Hasnat MA Ikeue K 《Chemical communications (Cambridge, England)》2006,(7):732-734
Selective electrocatalytic hydrogenation of NO3- to N2 in water has successfully been achieved at room temperature using a membrane-electrode assembly (MEA) consisting of an H+ -conducting solid polymer electrolyte (Nafion-117) and a surface-modified Pt cathode. 相似文献
993.
Kikuchi H Kitano M Takeuchi M Matsuoka M Anpo M Kamat PV 《The journal of physical chemistry. B》2006,110(11):5537-5541
TiO(2) thin films prepared by a radio frequency magnetron sputtering (RF-MS) deposition method were found to show an enhanced photoelectrochemical response in the visible light region. By controlling the temperature and the gaseous medium during the deposition step, it was possible to control the properties of these films. The photoelectrochemical behavior of the sputtered TiO(2) thin films was compared with that of a commercial TiO(2) sample, and the sputtered films showed higher incident photon to the charge carrier generation efficiency (IPCE of 12.6% at 350 nm) as well as power conversion efficiency (0.33% at 1.84 mW/cm(2)) than the commercial TiO(2) sample. Femtosecond transient absorption spectroscopy experiments have revealed that a major fraction of photogenerated electrons and holes recombine within a few picoseconds, thus limiting photocurrent generation efficiency. The mechanistic insights obtained in the present study should aid in designing semiconductor nanostructures that will maximize the charge separation efficiency and extend the response of the large band gap semiconductor TiO(2) into visible light regions. 相似文献
994.
995.
996.
Kitagawa F Inoue K Hasegawa T Kamiya M Okamoto Y Kawase M Otsuka K 《Journal of chromatography. A》2006,1130(2):219-226
Avidin was immobilized covalently onto the inner surface of fused silica capillaries as a stationary phase in an open tubular capillary electrochromatography (OT-CEC) for chiral separations. The modification was attained by a combination of glutaraldehyde with both an amino-silylated fused silica surface and avidin using a Schiff base formation reaction. This method couples the advantage of high efficiency and small consumption of a chiral selector with the possibility of UV detection without limitations of protein absorption. In addition, the prepared capillary was stable for 50 days with over 100 runs. To evaluate the electrochromatographic performance of the prepared capillaries, the chiral separation of abscisic acid and arylpropionic acids were investigated. Effects of the modification condition of protein, pH of running buffer, and an organic modifier on the enantioseparation were also investigated. In addition, the avidin immobilized capillary was employed for the selective chiral analysis with an electrospray ionization mass spectrometry (ESI-MS) detection scheme. 相似文献
997.
In this paper, we give a lower bound of the p-part of the reducedEuler characteristic of the order complex of the centric p-radicalsubgroups by studying vertices of indecomposable summands ofthe reduced Lefschetz module. This bound is in fact best possiblefor at least some groups, and also provides a uniform explanationof the observed phenomenon on the reduced Euler characteristicfor some sporadic simple groups. 相似文献
998.
Fukuda Takahito Shinomura Masato Xia Peng Awatsuji Yasuhiro Nishio Kenzo Matoba Osamu 《Optical Review》2017,24(2):206-211
Optical Review - We constructed a parallel-phase-shifting digital holographic microscopy (PPSDHM) system using an inverted magnification optical system, and succeeded in three-dimensional (3D)... 相似文献
999.
1000.
Teruaki Asai 《代数通讯》2013,41(19):2187-2201