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Effective Diffusion Coefficients of Glucose in Artificial Biofilms
Environmental Technology, 2005A technique using horizontal attenuated total reflection (HATR) by Fourier transform infrared (FTIR) spectrometry was demonstrated for the determination of effective diffusion coefficient (De) of an inert solute in biofilm. Glucose was the selected solute, and agarose (1%) hydrogel films containing various concentrations of activated sludge biomass ...
Zhang, T, Fang, HHP
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Effective diffusion coefficients in coal chars
Proceedings of the Combustion Institute, 2000Knowledge of effective diffusion coefficients in char particles is important when interpreting experimental reactivity measurements and modeling char combustion or NO and N 2 O reduction. In this work. NO and N 2 O reaction with a bituminous coal char was studied in a fixed-bed quartz glass reactor.
Jan E. Johnsson, Anker Jensen
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Effective Diffusion Coefficient
Defect and Diffusion Forum, 2018The diffusion of a B element into an A matrix was studied by the random walk theory. Considering that concentration of B element in the A matrix is very low, the jumps of diffusing atoms are independent of each other. The A matrix is a two-region material with different properties, such as a two-phase material, a single crystal with dislocations, or ...
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Effect of micropores on the effective diffusion coefficient
Kinetics and Catalysis, 2016The effective diffusion coefficient for catalysts differing in their porous structure has been derived from experimental data on H2S conversion in the Claus reaction. The effective diffusion coefficient increases under conditions of catalyst deactivation due to sulfur condensation in micropores.
V. M. Khanaev +3 more
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Ageing effect of chloride diffusion coefficient
ConcreteLife'06 - International RILEM-JCI Seminar on Concrete Durability and Service Life Planning: Curing, Crack Control, Performance in Harsh Environments, 2006Most of the currently used models to predict chloride ingress a constant diffusion coefficient over time. However, a reduction of the diffusion coefficient over time, is ob-served at specimens that are exposed to chlorides. This reduction of the diffusion coefficient is expressed with the ageing coefficient.
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Effective diffusion coefficient for two-band systems
Applied Physics Letters, 2005The effective longitudinal diffusion coefficient for two-band systems is determined. Emphasis is put on the nonlinear transport regime realized at high electric fields. Particular results are obtained for bipolar transport in two-band semiconductors and vertical transport in semiconductor superlattices.
P. Kleinert, V. V. Bryksin
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Effective diffusion coefficient in 2D periodic channels
The Journal of Chemical Physics, 2014Calculation of the effective diffusion coefficient D(x), depending on the longitudinal coordinate x in 2D channels with periodically corrugated walls, is revisited. Instead of scaling the transverse lengths and applying the standard homogenization techniques, we propose an algorithm based on formulation of the problem in the complex plane.
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Effective diffusion coefficients in solid-state sintering
Acta Materialia, 2004A numerical analysis of the sintering neck growth rate between rigid spherical particles of the same size is carried out. The contributions of the surface, grain-boundary and volume diffusion transport into sintering kinetics during the first and the second stages of sintering are estimated.
Andrey L. Maximenko, Eugene A. Olevsky
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Effective Diffusion Coefficient in Void Regions
Nuclear Science and Engineering, 1962The muitigroup diffusion theory for a virtually critical medium with homogeneous regions, when applied to a void region having one-dimensional cylindrical geometry, yields slightly erroneous results as a result of the fact that the theory ignores the neutron current traversing the gap.
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Time-dependent neutron diffusion coefficient for the effective diffusion equation
Progress in Nuclear Energy, 2019Abstract The time-dependency of neutron diffusion coefficient as well as neutronic interfacial coefficients in nuclear reactors at short time-scale is investigated via the volume averaging method. The boundary-value problems of governing differential equation for spatial deviations around averages of local variables are developed in this work.
Carlos G. Aguilar-Madera +2 more
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