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Estimation of kinetic and

A hierarchical series of ab initio methods was applied to obtain benchmark potential energy surface for the oxidative addition of methane to the Pd atom. The best estimate of kinetic and thermodynamic parameters is -8.1 kcal mol for the formation of the reactant complex, 5.8 kcal mol for the activation energy relative to the separate reactants, and 0.8 kcal mol for the reaction energy. The values agree well with those obtained by Siegbahn et al. with the PCI-80 method. Calculations were based on a model reaction involving the f --C,H transition state. [Pg.360]

The models that were actually used in the estimation of kinetic and thermodynamic parameters are reviewed here. Roughly speaking, two kinds of models are very dominating, namely algebraic models and differential models. Algebraic models consist of nonlinear equation systems (linear equation systems are obtained only for linear kinetics under isothermal conditions), whereas differential models consist of ODEs (provided that ideal flow conditions prevail in the test reactor). [Pg.584]

I. Betova, M. Bojinov, V. Karastoyanov, P. Kinnunen, T. Saario, Estimation of kinetic and transport parameters by quantitative evaluation of EIS and XPS data, Electrochim. Acta 55 (21) (2010) 6163-6173. [Pg.147]

S. Penttila, I. Betova, M. Bojinov, P. Kinnunen, A. Toivonen, Oxidation model for construction materials in supercritical water — estimation of kinetic and transport parameters, in 7th International Symposium on Supercritical Water-Cooled Reactors (lSSCWR-7), March 15-18, 2015. Helsinki, Finland, Paper 2064. [Pg.147]

S. Leveneur, J. Warna, K. Eranen, T. Salmi, Green process technology for peroxycarboxylic acids Estimation of kinetic and dispersion parameters aided hy RTD measurements Green synthesis of peroxycarboxylic acids, Chem. Eng. Sci. 66 (2011) 1038—1050. [Pg.664]

Suffice it to say that a dynamic model of this system was proposed that allowed the estimation of kinetic parameters and gave reasonable agreement with the experimental observations in the bioreactor [22]. [Pg.562]

For example, at 60°C, = 2300 and = 2.9 x 10. An estimate of kinetic chain lifetime, ie, the time from initiation to termination by reaction with... [Pg.466]

The main sources of deviation lie in estimates of energy and in release-process details. It is unclear whether the energy equations given in preceding sections are good estimates of explosion energy. In addition, energy translated into kinetic... [Pg.222]

The proposed subsequent reaction fits the fragmentation patterns observed in mass spectrometry where, even at 20 eV, group 14 centered radicals form in increasing order Sibasic data of this kind can provide estimates of kinetic behavior of such reactions, where M—M bonds are cleaved by electrophiles and which depend on the ionization potentials of the former as well as the electron affinity of the latter. [Pg.707]

This growth expression requires a minimum of kinetics and stoichiometric coefficients to be determined, and no hydraulic details are included. The dynamics of sewer biofilm detachment are not quantitatively known, and a steady state biofilm with a biomass release to the bulk water phase, equal to the biomass growth within the biofilm, is therefore an estimate. [Pg.109]

Kappeler, J. and W. Gujer (1992), Estimation of kinetic parameters of heterotrophic biomass under aerobic conditions and characterization of wastewater for activated sludge modelling, Water Sci. Tech., 25(6), 125-139. [Pg.126]

Funaki, T., Takanohashi, Y., Fukazawa, H. and Kuruma, I. (1991) Estimation of kinetic parameters in the inactivation of an enzyme by a suicide substrate. Biochimica et Biophysica Acta, 1078 (1), 43-46. [Pg.242]

A class of statistical methods frequently used to analyze kinetic and thermodynamic data. Most of these methods require a preliminary estimate of the constants followed by cycles of iterative calculations that converge on a final value(s). Cleland has presented a protocol for the statistical estimation of kinetic data. A nonlinear analysis has also been applied to progress curves. ... [Pg.509]

The fast stage of relaxation of a complex reaction network could be described as mass transfer from nodes to correspondent attractors of auxiliary dynamical system and mass distribution in the attractors. After that, a slower process of mass redistribution between attractors should play a more important role. To study the next stage of relaxation, we should glue cycles of the first auxiliary system (each cycle transforms into a point), define constants of the first derivative network on this new set of nodes, construct for this new network an (first) auxiliary discrete dynamical system, etc. The process terminates when we get a discrete dynamical system with one attractor. Then the inverse process of cycle restoration and cutting starts. As a result, we create an explicit description of the relaxation process in the reaction network, find estimates of eigenvalues and eigenvectors for the kinetic equation, and provide full analysis of steady states for systems with well-separated constants. [Pg.110]

The latter number incorporates just the chemical step(s) of formation of triazole within cucurbituril. Since the product release step apparently is at least 100-fold slower than the actual cycloaddition, the net catalytic acceleration should be adjusted downward by that amount. An instructive alternative estimation of kinetic enhancement is to compare the extrapolated limiting rate for cycloaddition within the complex (i.e. cucurbituril saturated with both reactants, k — 1.9xl0 s ) with the uncatalyzed unimolecular transformation of an appropriate bifunctional reference substrate as in Eq. (3) (k, = 2.0x 10 s ). Such a comparison of first-order rate constants shows that the latter reaction is approximately a thousandfold slower than the cucurbituril-engendered transformation. This is attributable to necessity for freezing of internal rotational degrees of freedom that exist in the model system, which are taken care of when cucurbituril aligns the reactants, and concomitantly to an additional consideration which follows. [Pg.19]

The cure kinetics of some epoxy resin powder coating composition were reported by Olcese et al.108). These were mixtures of BADGE resins with DICY and an epoxide-amine adduct or an imidazole as accelerator, together with TiOz and plasticisers. Data from DSC scans were analysed using Eq. (2-12) to obtain the apparent activation energy, E. Also Eq. (2-13) and (2-13 a) were used to obtain estimates of E and order... [Pg.144]

Several experimental approaches have been used to obtain information concerning the identity, concentrations, and reactivities of intermediates in catalytic reactions. Tamaru 136), during measurements of catalytic activity, concurrently determined the total quantity of gas adsorbed. One possible limitation to this method is that a proportion of the material bonded to the surface may not be involved in the surface reactions (57), The use of labeled reactants and monitoring the radioactivity in the region of the active solid may (95) provide a potentially useful technique for the estimation of Cj and/or c2. An alternative, and perhaps complementary, approach is through the individual investigation of the kinetics of product formation from reactions of known amounts of adsorbed material. This method has been used to elucidate some of the elementary steps in the breakdown of methanol on platinum (80). The independent preparation of a postulated intermediate,... [Pg.266]

DeLaat, J., P. Berger, T. Poinot, N. Karpel vel Leitner, and M. Dore (1997). Modeling the oxidation of atrazine by H202/UV. Estimation of kinetic parameters. Ozone Sci. Eng., 19 395 -08. [Pg.350]

M. Farza, K. Busawon, and H. Hammouri. Simple nonlinear observers for on-line estimation of kinetic rates in bioreactors. Automatica, 34 301-318, 1998. [Pg.118]


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Kinetic, estimated

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