Results 271 to 280 of about 224,627 (303)

Pre-exponential factor of the hopping conductivity in disordered carbon films

Bulletin of the Lebedev Physics Institute, 2010
The conductivity of carbon films grown by polymethylphenylsiloxane vapor decomposition in stimulated dc discharge plasma was studied. It is found that the Mott hopping conductivity \( \sigma \left( T \right) = \sigma _0 \left( T \right)\exp \left\{ { - \frac{{T_0 }} {T}^{{1 \mathord{\left/ {\vphantom {1 4}} \right.
E. A. Kataeva, A. D. Bozhko, S. V. Demishev   +2 more
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The structure of the thermal explosion limit with variable pre-exponential factor

Russian Journal of Physical Chemistry B, 2010
An approximate critical explosion parameter, which separates the slow and explosive reactions is determined with respect to the initial data, using the asymptotic technique to analyze a one step reaction mechanism with temperature dependent pre-exponential factor.
S. O. Ajadi, Vl. Gol’dshtein
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The Pre-exponential Factors for Unimolecular Gas-phase Reactions

Russian Chemical Reviews, 1972
The principal concepts and methods whereby the pre-exponential factors for unimolecular gas-phase reactions may be found have been examined. The methods are based on the transition state theory which accounts successfully for all experimental data. The reactions have been classified taking into account the typical structure of the activated complex ...
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Determination of the pre-exponential factor of Henry's constant by gas adsorption chromatography

Journal of Chromatography A, 1976
Abstract The pre-exponential factor of Henry's constant is important in studies of heterogeneity effects and is required for evaluating the correct distribution of adsorption energy. This factor has been determined by gas adsorption chromatography using experimental retention volumes measured for different adsorbate pressures and temperatures.
J. Gawdzik, Z. Suprynowicz, M. Jaroniec
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Experimental Definition of k-power of Pre-Exponential Voltage Factor for LAFE

2018 31st International Vacuum Nanoelectronics Conference (IVNC), 2018
In this work we used the possibilities of a comprehensive research methodology for LAFE. To determine the degree of the voltage in the pre-exponential factor, we used the IVC differentiation method and the method of minimization trend residue by variation Fowler-Nordheim coordinates.
E.O. Popov, A.G. Kolosko, S.V. Filippov
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The pre‐exponential factor and its importance in determining mechanism: the bromine electrode

Chemie Ingenieur Technik, 1972
AbstractThe rate of the reaction 2Br− = Br2 + 2 e at Pt electrodes has been studied in the temperature range 0 – 50 °C. Hence the enthalpy of activation was found to be 15 kJ mol−1. The preexponential factor was calculated using various assumptions and it is shown that the most probable rate‐determining step in this reaction is Br− → Br (ads) + e, the ...
K. D. Allard, R. Parsons
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The effect of variable pre-exponential factor on the ignition time of a homogeneous system

International Communications in Heat and Mass Transfer, 2004
CT The influence of variable pre-exponential factor on the ignition time of a system of homogeneous three step reaction mechanism is investigated. Based on simple numerical analysis, it is shown that for the ignition time over a broad range of realistic constant, the variation of pre-exponential factor leads to significant departure from the Arrhenius ...
S.O. Ajadi, S.S. Okoya
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The pre-exponential factor in the conductivity of undoped hydrogenated amorphous silicon

Philosophical Magazine B, 1985
Abstract In recent papers, Mott has suggested that the pre-exponential factor σ0 in the conductivity of a-Si: H, expressed in the form σ=σ0 exp [-(E c–E F)/kT], should be σ0 = 0·03 e 2/hL i, where L i is the inelastic diffusion length. Using experimental estimates of the time between collisions he finds sigma;0 16 ω−1 cm−1.
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The coverage dependence of the sticking coefficient and the desorption pre-exponential factor

Surface Science, 1989
Abstract Two models, accounting for the dependence of the partition function of the activated complex on the number of the nearest-neighbour adsorbed particles and the adsorbate-induced surface reconstruction, are shown to result in a strong coverage dependence of the pre-exponential factor for desorption.
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Charge-Carrier Injection and the Pre-exponential Factor in Semiconducting Organic Substances

The Journal of Chemical Physics, 1969
A charge-carrier injection model is shown to lead to an approximately linear dependence of the preexponential factor on activation energy for small organic semiconductors, without assuming a linear temperature dependence for the activation energy.
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