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decreases with increasing solvent polarity. Moreover, the reaction kinetics obeys a second-order rate law in toluene, butyl acetate, cyclohexanone and pyridine, but a first-order rate law is valid in NMP and DMF, and there is no distinction for the

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mL aqueous alcoholic solution, temperature 313 ± 1 K Thus, the reaction kinetics can be described by the equation: where r is the disappearance rate of 3-phenoxybenzaldehyde, k is an apparent rate

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Abstract

Hydrogen phosphate (HPO4 2−) or poly(acrylic acid) (PAA) stabilized cobalt(0) nanoclusters were in situ generated from the reduction of cobalt(II) chloride during the catalytic hydrolysis of sodium borohydride (NaBH4) in the presence of stabilizers, HPO4 2− or PAA. Cobalt(0) nanoclusters stabilized by HPO4 2− or PAA were characterized by using UV–Visible spectroscopy, TEM, XPS and FT-IR techniques. They were employed as catalysts in the hydrolysis of NaBH4 to examine the effect of stabilizer type on their catalytic activity and stability. Detailed reaction kinetics of the hydrolysis of NaBH4 in the presence of both catalysts was studied depending on catalyst concentration, substrate concentration and temperature. PAA stabilized cobalt(0) nanoclusters provided higher total turnover number (TTON = 6,600) than that of HPO4 2− stabilized cobalt(0) nanoclusters (1,285 turnovers). However, the HPO4 2− stabilized cobalt(0) nanoclusters provided a lower activation energy (E a = 53 ± 2 kJ mol−1) than the PAA stabilized cobalt(0) nanoclusters (E a = 58 ± 2 kJ mol−1) for the hydrolysis of NaBH4. The use of two types of stabilizers in the preparation of the same metal(0) nanoclusters following the same methodology enables us to compare the electrostatic and steric stabilization in terms of the catalytic activity and stability of metal(0) nanoclusters.

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in the journal last year ( Reaction Kinetics, Mechanisms and Catalysis , 2010 , 101, 129–140; DOI 10.1007/s11144-010-0210-2 ). After the publication of the paper, the following facts became obvious to the editors. 1. The

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, T.P. , KAMMAN , J. ( 1983 ): Reaction kinetics and accelerated tests simulation as a function of temperature . -in: SAGUY , I. (Ed.) Applications of computers in food research , Marcel Dekker , New York . Chapter 4

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reakciókinetikai megközelítés . (Research results in 1998 and new approach to modell reaction kinetics of vitamin C decomposition.) Research report, project OTKA T 014965, task: 2.4. Szent István University, Faculty of Food Science, Department of Canning

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the reaction kinetics occurring on a uniform surface and single sites, we have recently analyzed a simple reaction scheme of N 2 O decomposition running in the presence of oxygen on Fe [ 4 ]. In this study, we treat a much more complex reaction

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Dannenberg, F. & Kessler, H. G. (1988): Reaction kinetics of the denaturation of whey proteins in milk. J.Fd Sci. , 53 , 258-263. Reaction kinetics of the denaturation of whey proteins in milk. J

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Acta Alimentaria
Authors: M. Ferreira, S. Pereira, A. Almeida, R. Queirós, I. Delgadillo, J. Saraiva, and A. Cunha

. R AMIREZ , R. , S ARAIVA , J. , L AMELA , C.P. & T ORRES , J.A. ( 2009 ): Reaction kinetics analysis of chemical changes in pressure-assisted thermal processing . Food Eng. Rev. , 1 , 16 – 30

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