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Diffusion effects diffusivity

All the aforementioned phenomena, which contribute jointly to spot broadening, are used to be described as the effective diffusion. Effective diffusion is a convenient notion, which, apart from being concise and informative, emphasizes that all the contributory phenomena occur simultaneously. [Pg.160]

Since the blocked gas inside of the capillary is dissolving in the liquid and then diffusing towards the exit of the channel, the meniscus of the liquid crosses the position l and goes deeper. This second stage of capillary filling with liquid is called diffusive imbibition and plays an important role in PT processes. The effect of diffusive imbibition upon PT sensitivity has been studied in [7]. [Pg.615]

Perez Quintian, M.A.Rebollo, N.G. Gaggioli y C.A. Raffo, The non refractive effect in translucent diffusers A geometrical model . Aprobado para su publicacion en Journal of Modem Opties. [Pg.668]

It was determined, for example, that the surface tension of water relaxes to its equilibrium value with a relaxation time of 0.6 msec [104]. The oscillating jet method has been useful in studying the surface tension of surfactant solutions. Figure 11-21 illustrates the usual observation that at small times the jet appears to have the surface tension of pure water. The slowness in attaining the equilibrium value may partly be due to the times required for surfactant to diffuse to the surface and partly due to chemical rate processes at the interface. See Ref. 105 for similar studies with heptanoic acid and Ref. 106 for some anomalous effects. [Pg.34]

The quantity 1 /k is thus the distance at which the potential has reached the 1 je fraction of its value at the surface and coincides with the center of action of the space charge. The plane at a = l//c is therefore taken as the effective thickness of the diffuse double layer. As an example, 1/x = 30 A in the case of 0.01 M uni-univalent electrolyte at 25°C. [Pg.173]

The effect known either as electroosmosis or electroendosmosis is a complement to that of electrophoresis. In the latter case, when a field F is applied, the surface or particle is mobile and moves relative to the solvent, which is fixed (in laboratory coordinates). If, however, the surface is fixed, it is the mobile diffuse layer that moves under an applied field, carrying solution with it. If one has a tube of radius r whose walls possess a certain potential and charge density, then Eqs. V-35 and V-36 again apply, with v now being the velocity of the diffuse layer. For water at 25°C, a field of about 1500 V/cm is needed to produce a velocity of 1 cm/sec if f is 100 mV (see Problem V-14). [Pg.185]

It is necessary that the mercury or other metallic surface be polarized, that is, that there be essentially no current flow across the interface. In this way no chemical changes occur, and the electrocapillary effect is entirely associated with potential changes at the interface and corresponding changes in the adsorbed layer and diffuse layer. [Pg.193]

Surface active electrolytes produce charged micelles whose effective charge can be measured by electrophoretic mobility [117,156]. The net charge is lower than the degree of aggregation, however, since some of the counterions remain associated with the micelle, presumably as part of a Stem layer (see Section V-3) [157]. Combination of self-diffusion with electrophoretic mobility measurements indicates that a typical micelle of a univalent surfactant contains about 1(X) monomer units and carries a net charge of 50-70. Additional colloidal characterization techniques are applicable to micelles such as ultrafiltration [158]. [Pg.481]

The repulsion between oil droplets will be more effective in preventing flocculation Ae greater the thickness of the diffuse layer and the greater the value of 0. the surface potential. These two quantities depend oppositely on the electrolyte concentration, however. The total surface potential should increase with electrolyte concentration, since the absolute excess of anions over cations in the oil phase should increase. On the other hand, the half-thickness of the double layer decreases with increasing electrolyte concentration. The plot of emulsion stability versus electrolyte concentration may thus go through a maximum. [Pg.508]

The rate of dissolving of a solid is determined by the rate of diffusion through a boundary layer of solution. Derive the equation for the net rate of dissolving. Take Co to be the saturation concentration and rf to be the effective thickness of the diffusion layer denote diffusion coefficient by . [Pg.592]

Bonig L, Liu S and Metiu FI 1996 An effective medium theory study of Au islands on the Au(IOO) surface reconstruction, adatom diffusion, and island formation Surf. Sot 365 87... [Pg.316]

The coefficients, L., are characteristic of the phenomenon of thermal diffusion, i.e. the flow of matter caused by a temperature gradient. In liquids, this is called the Soret effect [12]. A reciprocal effect associated with the coefficient L. is called the Dufour effect [12] and describes heat flow caused by concentration gradients. The... [Pg.702]

Figure A3.6.13. Density dependence of die photolytic cage effect of iodine in compressed liquid n-pentane (circles), n-hexane (triangles), and n-heptane (squares) [38], The solid curves represent calculations using the diffusion model [37], the dotted and dashed curves are from static caging models using Camahan-Starling packing fractions and calculated radial distribution fiinctions, respectively [38],... Figure A3.6.13. Density dependence of die photolytic cage effect of iodine in compressed liquid n-pentane (circles), n-hexane (triangles), and n-heptane (squares) [38], The solid curves represent calculations using the diffusion model [37], the dotted and dashed curves are from static caging models using Camahan-Starling packing fractions and calculated radial distribution fiinctions, respectively [38],...
If a fluid is placed between two concentric cylinders, and the inner cylinder rotated, a complex fluid dynamical motion known as Taylor-Couette flow is established. Mass transport is then by exchange between eddy vortices which can, under some conditions, be imagmed as a substantially enlranced diflfiisivity (typically with effective diflfiision coefficients several orders of magnitude above molecular difhision coefficients) that can be altered by varying the rotation rate, and with all species having the same diffusivity. Studies of the BZ and CIMA/CDIMA systems in such a Couette reactor [45] have revealed bifiircation tlirough a complex sequence of front patterns, see figure A3.14.16. [Pg.1112]

Hwang L-P and Freed J H 1975 Dynamic effects of pair correlation functions on spin relaxation by translational diffusion in liquids J. Chem. Rhys. 63 4017-25... [Pg.1516]

Carr H Y and Purcell E M 1954 Effects of diffusion on free precession in nuclear magnetic resonance experiments Rhys. Rev. 94 630-8... [Pg.1517]

Ahn C B and Cho Z H 1989 A generalized formulation of diffusion effects in pm resolution nuclear magnetic-resonance imaging Med. Rhys. 16 22-8... [Pg.1545]

Broadening of spots can result from themial diffuse scattering and island fomiation, among other causes. The themial effects arise from the disorder in atomic positions as they vibrate around their equilibrium sites the sites themselves may be perfectly crystalline. [Pg.1769]

In most practical cases (and at moderate voltages) the high-field growth law can control film growth, say up to only a maximum of 10 nm, as at this thickness the field strength effects become even less important than film growth due to diffusion of vacancies or ions. [Pg.2724]

Caldin E F, de Forest L and Queen A 1990 Steric and repeated collision effects in diffusion-controlled reactions in solution J. Chem. See. Faraday Trans. 86 1549-54... [Pg.2850]

C3.6.13 where large diffusion fluxes are indicated by —> and smaller diffusion fluxes by —+. For tire part of tire B front tliat protmdes into tire A region, fast diffusion of B leads to dispersal of B and suppresses tire autocatalytic reaction tliat requires two molecules of B. The front will have difficulty advancing here. In tire region where A protmdes into B, A will react leading to advancement of tire front. The net effect is to remove any initial nonplanarity and give rise to a planar front. [Pg.3070]


See other pages where Diffusion effects diffusivity is mentioned: [Pg.485]    [Pg.104]    [Pg.47]    [Pg.41]    [Pg.393]    [Pg.848]    [Pg.849]    [Pg.511]    [Pg.523]    [Pg.560]    [Pg.737]    [Pg.891]    [Pg.1109]    [Pg.1685]    [Pg.1769]    [Pg.1938]    [Pg.2111]    [Pg.2421]    [Pg.2489]    [Pg.2498]    [Pg.2501]    [Pg.2502]    [Pg.2731]    [Pg.2790]    [Pg.2806]    [Pg.2838]    [Pg.2842]    [Pg.2895]    [Pg.3064]    [Pg.3071]    [Pg.366]   


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Acid diffusion effect

Additional base component effect acid diffusion

An Effective Diffusion Model

Anomalous diffusion effective temperature

Apparent effective hydrogen diffusivity

Arrhenius behavior, effective diffusivity

Assessment of relaxation times, MT effects and diffusion characteristics

Boundary conditions effective diffusivity model

Calculation of effective diffusivities

Capillary waves diffusion, effect

Carrots effective diffusivity

Carrots effective moisture diffusivity

Catalysts, general diffusion effects

Catalytic effective diffusivity

Catalytic reactions pore diffusion effects

Coked zeolite, diffusivity effect

Cross-diffusion effect

Deactivating catalysts pore diffusion effects

Diffuse double-layer effects, electrical

Diffuse functions, effect

Diffuse functions, effect acidities

Diffuse functions, effect anion geometries

Diffuse functions, effect bond separation

Diffuse functions, effect energies

Diffuse interface effective width

Diffusion Effectiveness factor)

Diffusion Effects During Cure

Diffusion Kirkendal effect

Diffusion Kirkendall effect

Diffusion and Mass-transfer Effects

Diffusion and reaction in pores. Effectiveness

Diffusion catalyst effectiveness

Diffusion classical aging effects

Diffusion coefficient absorption effect

Diffusion coefficient effective

Diffusion coefficient effective diffusivity

Diffusion coefficient effective transition region

Diffusion coefficient effects

Diffusion coefficient hydrodynamic effect

Diffusion coefficient ionic atmosphere effect

Diffusion coefficient solvent viscosity effect

Diffusion coefficient, effective axial

Diffusion coefficient, effective dual-mode

Diffusion coefficient, effective thermodynamic

Diffusion coefficients, effects Brownian motion

Diffusion coefficients, effects dynamical friction

Diffusion coefficients, effects theory

Diffusion concentration effect

Diffusion constant viscosity effects

Diffusion controlled reaction, transient effects

Diffusion crosslinking effect

Diffusion current absorptive effects

Diffusion current kinetic effects

Diffusion density effect

Diffusion effect

Diffusion effective

Diffusion effective

Diffusion effective binary

Diffusion effective charge

Diffusion effective diffusivity

Diffusion effective temperature

Diffusion effective thickness

Diffusion effects Nemst

Diffusion effects analysis

Diffusion effects burning within particle

Diffusion effects carbon burning reaction

Diffusion effects determination

Diffusion effects elimination

Diffusion effects experimental verification

Diffusion effects external

Diffusion effects first order reactions

Diffusion effects gaseous

Diffusion effects independence

Diffusion effects internal

Diffusion effects intraparticle

Diffusion effects involving reaction rates

Diffusion effects irregularly shaped particles

Diffusion effects laminar flow

Diffusion effects longitudinal

Diffusion effects measurements

Diffusion effects on biomoleeular reactions

Diffusion effects outside catalyst particle

Diffusion effects reactant concentration

Diffusion effects through catalyst particles

Diffusion effects through particle

Diffusion effects velocity constant

Diffusion effects within catalyst

Diffusion effects within catalyst particle

Diffusion effects, electron-transfer

Diffusion effects, electron-transfer bulk reaction

Diffusion effects, electron-transfer reactivity

Diffusion effects, electron-transfer structure

Diffusion effects, surface

Diffusion flames buoyancy effects

Diffusion flux/effective coefficient

Diffusion internal effectiveness factor

Diffusion internal viscosity effect

Diffusion layer effective boundary

Diffusion limitation effects

Diffusion limited current density effective

Diffusion magnetic field effects

Diffusion microstructure effects

Diffusion model, structure effect

Diffusion modified effective binary

Diffusion overall effectiveness factor

Diffusion overlapping effect

Diffusion polarization, solution velocity effect

Diffusion polymerization rate, effect

Diffusion quantum aging effects

Diffusion saturation effect

Diffusion shielding effect

Diffusion skin effect

Diffusion temperature effects

Diffusion terminal velocity, effect

Diffusion wall effect

Diffusion, bulk Effectiveness factor

Diffusion-controlled processes, pressure effects

Diffusion-limited regime effectiveness factor

Diffusion-reaction problems potential effects

Diffusion-thermo effect

Diffusivities effectiveness factor

Diffusivities structure effect

Diffusivity correlation effects

Diffusivity effective medium approximation

Diffusivity effectiveness factor

Diffusivity pressure effect

Diffusivity temperature effect

Diffusivity, bulk effective

Diffusivity, effective, polymer fractionation modeling

Drying supported catalyst diffusion, effect

Dufour effect, thermal diffusion

Edge diffusion effects

Effect of Diffusion and Exchange

Effect of Diffusion on Rate

Effect of Unequal Diffusion Coefficients

Effect of diffusion

Effect of diffusion resistance

Effect of external diffusion limitation

Effect of internal diffusion limitation

Effect of intraparticle diffusion on experimental parameters

Effect of longitudinal diffusion

Effect of sucrose on the bimolecular diffusion constant

Effect on diffusivity

Effective Diffusivities in Biological Gels

Effective Diffusivities in Multicomponent Mixtures

Effective Ionic Diffusivities

Effective Theories of Diffusion

Effective binary diffusivity

Effective catalyst layer Knudsen diffusion

Effective catalyst layer diffusivity

Effective coefficient of diffusion

Effective diffusion coefficient Brownian dynamics

Effective diffusion coefficient continuum

Effective diffusion coefficient definition

Effective diffusion coefficient discrete phase

Effective diffusion coefficient empirical expressions

Effective diffusion coefficient material

Effective diffusion coefficient penetrant concentration

Effective diffusion coefficient polymer degradation

Effective diffusion coefficient porous layer

Effective diffusion coefficient procedures

Effective diffusion coefficient relations from different equations

Effective diffusion coefficient volume

Effective diffusion coefficient, Df

Effective diffusion models

Effective diffusion time

Effective diffusivities

Effective diffusivities

Effective diffusivities calculated

Effective diffusivities in porous catalysts

Effective diffusivity

Effective diffusivity

Effective diffusivity concept

Effective diffusivity film model

Effective diffusivity ionic

Effective diffusivity limiting cases

Effective diffusivity methods

Effective diffusivity model

Effective diffusivity model endothermic reactions

Effective diffusivity multicomponent liquid mixtures

Effective diffusivity stagnant mixture

Effective diffusivity steady-state diffusion

Effective diffusivity, definition

Effective diffusivity, measurement

Effective diffusivity, polymer

Effective diffusivity, porous media

Effective gas diffusivity

Effective length, diffusion

Effective moisture diffusivity

Effective molecular diffusion coefficient

Effective single-file diffusion

Effective surface diffusivity

Effective terms diffusion

Effective theory diffusion

Effective thermal diffusivity

Effective thickness, of diffusion

Effectiveness factor diffusion, porous catalyst

Effectiveness factor effective diffusivity model

Effectiveness factor for first-order irreversible reaction-diffusion system

Effects of Brownian Diffusion on Deposition

Effects of Diffusion within Catalyst Particles

Effects of Diffusion within Immobilized Enzyme Particles

Effects of Rotational Diffusion on Fluorescence Anisotropies The Perrin Equation

Effects of intraparticle diffusion on the experimental parameters

Effects of pore diffusion

Electron-transfer . nonadiabatic solvent diffusion effects

Electrostatic potential diffusion effect

Energy transfer diffusion effects

Experimentation, effective diffusivity

Experimentation, effective diffusivity determination

Experimentation, effective diffusivity isolation method

Experimentation, effective diffusivity residence time determination

Experimentation, effective diffusivity temperature control

Extraction effective diffusivity method

Factor effective diffusion

Film theory effective diffusivity method

Fischer—Tropsch synthesis diffusivity effects

Fluxes with an Effective Diffusivity Model

Fractional rotational diffusion inertial effects

Heat diffusion effect

Heterogeneous reactions external diffusion effects

Intraparticle diffusion effectiveness factor

Intrinsic Diffusion Coefficient The Kirkendall Effect

Isobutylene, effective diffusivity

Lateral diffusion cholesterol, effect

Lemon effective diffusivity

Liquid diffusion pressure effects

Liquid diffusion temperature effects

Mass transfer coefficient liquid phase diffusivity effect

Mass-transfer measurements effective diffusivities

Mechanical behavior diffusion effects

Medium effects diffusion

Medium effects self-diffusion

Mixing and Diffusion Effects

Modeling effective diffusion coefficient

Moisture, diffusion effects

Molar flux in terms of effective diffusivity

Molecular diffusion, effect

Molecular diffusion, effect dispersivity

Molecular diffusivity, effect

Molecular diffusivity, effect model selection

Multicomponent diffusion, effective binary

Multicomponent diffusion, effective binary diffusivity

Nitrogen effective diffusivity

Nuclear Overhauser effect spin diffusion

Organic matter degradation, effects diffusion

Oscillations diffusion effects

Oxygen diffusion coefficient temperature effect

Oxygen diffusion effects

Oxygen diffusion effects degradation

Oxygen diffusion effects oxidation

Oxygen diffusion effects oxidation depth

Oxygen diffusion effects polymer

Para-xylene selectivity diffusivity effects

Pellets effective diffusivity

Poly , size effects diffusion

Pore Diffusion Resistance and Effective Reaction Rate

Pore diffusion effects

Pore diffusion, mass transport effect

Pore effective diffusion coefficient

Porous solids effective diffusivity

Propylene, effective diffusivity

Pulsed gradient spin echo diffusion effect

Ratio apparent effective diffusivities

Reaction diffusion solvent effects

Reaction diffusion substituent effects

Reaction diffusion template effects

Reaction effective diffusivity

Reaction rate pore diffusion effect

Reducing the Effect of Longitudinal Diffusion

Reduction diffusion effects during

Response time effective diffusion length

Role of diffusion in pellets Catalyst effectiveness

Rotational diffusion effects

Self-diffusion topological effect

Single effective diffusivity

Solvent diffusion polymer effect

Soret effect, thermal diffusion

Spherical catalyst pellets effective diffusivity

Spin diffusion effect

Taylor dispersion effective diffusivity

Temperature effect on diffusivity

Temperature effects and diffusion

The Effect of B-Site Cation on Oxygen Diffusivity

The Effect of Diffusion Limitation

The Effective Diffusion Coefficient

The Effective Diffusivity—Closing Remarks

The effective diffusivity

Thermal diffusion effects

Thermal diffusion length, effect

Thermal diffusion length, effect experiment

Tracer diffusion effect

Two Bulb Diffusion Cell A Test of the Effective Diffusivity

Viscosity effect upon diffusion

Water, effective diffusivity

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