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991.
Donghui Wang Zhengping Hao Daiyun Cheng Xicheng Shi Chun Hu 《Journal of molecular catalysis. A, Chemical》2003,200(1-2):229-238
Composite oxide MOx/Al2O3 supported gold catalysts for low-temperature CO oxidation were prepared and investigated. The presence of transition metal oxide was proved to be beneficial to the improvement of catalytic performance of Au/Al2O3 catalysts for low-temperature CO oxidation. Furthermore, the influence of various pretreatment conditions on Au/MOx/Al2O3 catalysts was studied carefully. The image of TEM showed that gold catalyst with small gold particles only in the form of a fine dispersion exhibited highly catalytic activity. The XPS, Fourier transform infrared (FTIR) spectroscopy characterization results of Au/FeOx/Al2O3 catalyst showed that gold catalysts having partially oxidized gold species have the best catalytic performance. One possible pathway for CO oxidation on Au/FeOx/Al2O3 catalyst is that the CO adsorbed on gold particles reacts with adsorbed oxygen, which is possible to occur on oxygen vacancies on the support or at the metal–support interface. 相似文献
992.
Summary A rapid and accurate LC method is described for simultaneous determination of pseudoephedrine hydrochloride (PSE), acetaminophen (AMP), dextromethorphen hydrobromide (DEX), and diphenhydramine hydrochloride (DPH) in a compound formulation. Chromatographic separation of the four drugs was achieved on a Hypersil CN column (150 mm × 4.6 mm, 5 m particle) by use of a mobile phase comprising a mixture of 3 mM ion-pairing solution, 2% aqueous triethylamine solution, and 2 M phosphoric acid, 68:48:88 (v/v), pH 3.0, delivered at 1.0 mL min–1. Compounds were detected at 215 nm and the run time was less than 10 min. The linearity, accuracy, and precision of the method were found to be acceptable over the concentration ranges 6.1–36.4 g mL–1 for PSE, 65.0–390.0 g mL–1 for AMP, 3.1–18.6 g mL–1 for DEX, and 5.0–30.0 g mL–1 for DPH. 相似文献
993.
Summary Two high-performance liquid chromatography (HPLC) techniques were developed for the determination of binding constants in
the interaction of serum albumin with L-tryptophan: internal calibration and external calibration. The results obtained were
compared with those obtained by the classical method of equilibrium dialysis and by gel filtration. While all the methods
are equally reliable, the internal and external calibration techniques seem to be superior in their simplicity, speed and
convenience. 相似文献
994.
We describe a space of functions contained inxxLx
(D)C(D G) but not necessarily inU. We give a representation of these functions as bounded multiplication operators on the Bergman spacexxLx
a
2
and identify the subspace consisting of functions which induce compact multiplication operators. We also describe a newC
*-subalgebra ofxxLx
(D) which we conjecture to be a proper super-set ofU.Most of this research was done while the second author was visiting Cleveland State University. He would like to thank the Mathematics Department for its hospitality. He would also like to thank the NNSFC for partial support. 相似文献
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Alam MS Kim IJ Nemati B O'Neill JJ Romero V Severini H Sun CR Wang P Zoeller MM Crawford G Fulton R Gan KK Kagan H Kass R Lee J Malchow R Morrow F Sung M White C Whitmore J Wilson P Butler F Fu X Kalbfleisch G Lambrecht M Skubic P Snow J Bortoletto D Brown DN Dominick J McIlwain RL Miao T Miller DH Modesitt M Schaffner SF Shibata EI Shipsey IP Battle M Ernst J Kroha H Roberts S Sparks K Thorndike EH Wang C Artuso M Goldberg M Haupt T Horwitz N Kennett R Moneti GC Playfer S Rozen Y Rubin P 《Physical review D: Particles and fields》1992,46(11):4822-4827