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A. A. Spojakina N. G. Kostova D. M. Shopov 《Reaction Kinetics and Catalysis Letters》1981,17(1-2):83-86
By means of DTA, reflectanc spectra and measurement of catalytic activity in thiophene hydrogenolysis, the effect of support (aluminium hydroxide and oxide) as well as of the order of introduction of molybdenum and cobalt compounds on the structure and catalytic surface of Co–Mo–Al2O3 catalysts is shown.
, ( ) , Co–Mo–Al2O3.相似文献
44.
γ-Nitro-γ-butyrolactone By oxidation of 3-(1-nitro-2-oxocyclohexyl)propanal ( 1 ) with KMnO4, besides 3-(1′-nitro-2′-oxocyclohexyl)pripionic acid ( 2 ), the complete hydrolysis product 4-oxononanedioic acid ( 4 ) and the oxidized semi-hydrolysis product 5-(2-nitro-5-oxotetrahydro-2-furyl)pentanoic acid ( 3 ) were formed. The crystalline 3 decomposes at r.t. forming 4 and nitrous gases; its structure was established by X-ray determination. 相似文献
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Two Mo/SiO2 samples have been prepared by impregnation of silica gel with aqueous solution of molybdophosphoric heteropoly acid or ammonium heptamolybdate. The catalysts were studied by ESR and IR spectroscopy, X-ray diffraction, and XPS. Their activity was measured in the reaction of thiophene hydrodesulfurization. The silica-supported P–Mo heteropoly acid, with a preserved Keggin structure of the heteropoly anion and sulfided by H2S, exhibited two times higher steady conversion in comparison with ammonium heptamolybdate supported on silica at pH=11 and calcined and sulfided at 500°C. 相似文献
47.
Spojakina A. A. Jiratova K. Kostova N. G. Kocianova J. Stamenova M. 《Kinetics and Catalysis》2003,44(6):813-818
H3PW12O40 heteropoly acid (HPW12) and its Co, Fe, Ni salts supported on alumina have been used to model hydrodesulfurization catalysts of different activity. All catalysts revealed a promoting effect of the countercation in thiophene hydrodesulfurization, that of the nickel cation being the highest. The catalysts were characterized by measurements of surface area, HDS activity, TPR, FTIR, and DR spectra. IR spectra confirmed an effect of the countercation on the phase composition of the supported heteropoly compounds. 12-Tungstoaluminate heteropoly anions and coordinately unsaturated anions of HPW12 were detected in the IR spectra of the catalysts. The hydrotreating activity of the catalysts was proportional to the amount of hydrogen consumed in the range 20–500°C during TPR. 相似文献
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We present a rare example of a decay mechanism playing a constructive role in quantum information processing. We show how
the state of an atom trapped in a cavity can be teleported to a second atom trapped in a distant cavity by the joint detection
of photon leakage from the cavities. The scheme, which is probabilistic, requires only a single three level atom in a cavity.
We also show how this scheme can be modified to a teleportation with insurance. 相似文献
50.
M. Amalanathan I. Hubert Joe Irena Kostova 《Journal of Raman spectroscopy : JRS》2010,41(9):1076-1084
The Fourier transform infrared (4000–400 cm−1) and Fourier transform Raman (3500–500 cm−1) spectra of 4‐hydroxy‐3‐(3‐oxo‐1‐phenylbutyl)‐2H‐1‐benzopyran‐2‐one (Warfarin) have been measured and calculated. The structure optimization has been made using density functional theory (DFT) calculations. Complete vibrational assignments of the observed spectra have been compared with theoretical wavenumbers. The wavenumber increasing in the methyl group shows the electronic hyperconjugation effect. The natural bond orbital (NBO) analysis reveals the hyperconjugation interaction and the intramolecular hydrogen bonding. The first‐order hyperpolarizability has been calculated. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献