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Gas model for

The complete problem with composition gradients as well as a pressure gradient, may be regarded as a "generalized Poiseuille problem", and its Solution would be valuable for comparison with the limiting form of the dusty gas model for small dust concentrations. Indeed, it is the "large diameter" counterpart of the Knudsen solution in tubes of small diameter. [Pg.25]

This determines the total flux at the li/nic of viscous flow. Equations (5.18 and (5.19) therefore describe the limiting form of the dusty gas model for high pressure or large pore diameters -- the limit of bulk diffusion control and viscous flow,... [Pg.39]

E. Albano. Displacement of inactive phases by the reactive regime in a lattice gas model for a dimer-monomer irreversible surface reaction. Phys Rev E 55 7144-7152, 1997. [Pg.434]

To make matters worse, the use of a uniform gas model for electron density does not enable one to carry out good calculations. Instead a density gradient must be introduced into the uniform electron gas distribution. The way in which this has been implemented has typically been in a semi-empirical manner by working backwards from the known results on a particular atom, usually the helium atom (Gill, 1998). It has thus been possible to obtain an approximate set of functions which often serve to give successful approximations in other atoms and molecules. As far as I know, there is no known way of yet calculating, in an ab initio manner, the required density gradient which must be introduced into the calculations. [Pg.105]

K). T is the measurement temperature and Tq is the "degeneracy temperature," equal to kEo, where k is the Boltzmann constant. According to a two-dimensional electron gas model for graphitic carbons (see ref. 2a), is the energy "shift" from the Fermi level (Ep), to the top of the valence band. Small values of To ( <344 K) and consequently of Eq signify a more perfect graphite... [Pg.507]

Koper MTM, Lukkien JJ, Jansen API, van Santen RA. 1999. Lattice gas model for CO electrooxidation on Pt-Ru bimetallic surfaces. J Phys Chem B 103 5522-5529. [Pg.406]

A. Malevanets and R. Kapral, Continuous-velocity lattice-gas model for fluid flow, Europhys. Lett. 44, 552 (1998). [Pg.141]

T. Sakai, Y. Chen, and H. Ohashi, Real-coded lattice gas model for ternary amphiphilic fluids, Phys. Rev. E 65, 031503 (2002). [Pg.146]

In solution, although solute contributions can generally be singled out, difficulties arise sometimes solvent-solute interactions may induce a shift of the solute absorption and consequently of its susceptibility or hydrogen bonded molecular complexes may modify the liquid structure. This situation has been studied both theoretically and experimentally by Zyss and Berthier (10) and by Ledoux and Zyss (13) in the case of urea derivatives in various solvents and in crystal showing the importance of environment considerations and thus the limitations of an oriented gas model for crystals. [Pg.84]

We should mention here the one dimensional hard point gas model for which anomalous heat conduction has been found by several authors (Dhar, 2003 Grassberger et al, 2002). However it seems there is no agreement on the numerical value of the exponent (3. Indeed in Ref.(Dhar, 2003), the value (3 0.25 has been found, while the value (3 0.33 is reported in (Grassberger et al, 2002). [Pg.17]

Leermakers, F. A. M. and Cohen Stuart, M. A. (1996). Self-consistent-field lattice gas model for the surface ordering transition of n-hexadecane, Phys. Rev. Lett., 76, 82-85. [Pg.103]

In this appendix, explicit functionals of the density representing the different relativistic corrections are found by performing expectation values taking Slater determinants of local plane waves as in the standard Fermi gas model. For a one-body operator we use ... [Pg.208]

Here we develop a heterogeneous model that is based on the more rigorous dusty gas model for diffusion and reaction in porous catalyst pellets. [Pg.509]

Veldsink J.W., van Damme R.M.J., Versteeg G.F., van Swaaij W.P.M., 1995. The use of the dusty-gas model for the description of transport with chemical reaction in porous media. Chemical Engineering and the Biomedical Engineering Journal 57(2), 115-125. [Pg.92]

Motivated by the need to consider finite size of ions in the PB model, Chu et al. employed a lattice gas model for the ionic system, where ions of finite sizes are placed on the grid cells. In this way, the ion size can be conveniently represented by the cell size and the system can be treated with the lattice gas approximation (Chu et al., 2007). The modified PB theory... [Pg.472]

Marinin, V.S., Umerenkova, K.R., Shmal ko, Yu.F. (2002) Interacting lattice gas model for hydrogen subsystem of metal hydrides, Functional materials 9(3), 395-401, (inRus.). [Pg.192]

The average behavior of the gas model for a motion of infinite duration... [Pg.23]

A. Wassmuth (1908) shows that among all distributions of the form p=F(E) only the canonical distribution satisfies the following requirement Let us consider only those (7-points of the ensemble which give a certain definite configuration (gi, , gf) to the molecules of the gas model for arbitrary values of the velocities. Now let us form for these particles the average of the square of a momentoid (see note 179). We require that this average... [Pg.64]

In this appendix expressions are derived for the pressure gradient inside catalyst pellets for nondiluted gases with the aid of the dusty gas model, for general equations [1]. Assume a mixture of A, P and m inert components Di (i = 1,2,m). A reacts to P according to ... [Pg.245]

At the opposite extreme from the oriented gas model for molecular crystals, the neighbouring molecules do interact with each other resulting in spectral properties of the bulk that differ considerably from those of the individual molecule. Interacting molecules of this type often tend to form aggregates even in solution, a phenomenon that has been exploited by the photographic industry for the tuning of the spectral response of silver halide emulsions (Herz 1974 Smith 1974 Nassau 1983). Aggregate formation can lead to the development of new, and often quite intense absorption bands... [Pg.229]

The N-gas models for predicting smoke toxicity were founded on the hypothesis that a small number N)... [Pg.645]

M. Molina-Sabio, F. Rodriguez-Reinoso, D. Valladares and G. Zgrablich, A lattice-gas model for adsorption in microporous solids, in J. Rouquerol, F. Rodriguez-Reinoso,... [Pg.113]

For low pressures (a few atmospheres and lower) we can apply the ideal gas model for gases and ideal mixture models for liquids. This formulation is very common in reactor technology. In some cases at higher pressures, the pressure effect on the gas phase is important. A suitable model for these systems is to use an EOS for the gas phase, and an ideal mixture model for liquids. However, in most situations at low pressures the liquid phase is more non-ideal than the gas phases. Then we will rather apply the ideal gas law for the gas phase, and excess properties for liquid mixtures. For polar mixtures at low to moderate pressures we may apply a suitable EOS for gas phases, and excess properties for liquid mixtures. All common models for excess properties are independent of pressure, and cannot be used at higher pressures. The pressure effect on the ideal (model part of the) mixture can be taken into account by the well known Poynting factor. At very high pressures we may apply proper EOS formulations for both gas and liquid mixtures, as the EOS formulations in principle are valid for all pressures. For non-volatile electrol3d es, we have to apply a suitable EOS for gas phases and excess properties for liquid mixtures. For such liquid systems a separate term is often added in the basic model to account for the effects of ions. For very dilute solutions the Debye-Htickel law may hold. For many electrolyte systems we can apply the ideal gas law for the gas phase, as the accuracy reflected by the liquid phase models is low. [Pg.54]

For the q - - 1-component pseudo-mixture we may modify the formulation of the Maxwell-Stefan equation given in the last line of (2.298) and the generalized diffusional driving force expression (2.283). The dusty gas model, for s = 1,2,..., q+l, yields ... [Pg.274]

Using vector notation the dusty gas model for the mass fluxes yields ... [Pg.292]


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See also in sourсe #XX -- [ Pg.225 ]




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Cross-Flow Model for Gas Separation by Membranes

Dispersion Model for Gas Synthesis Reactors

Dusty Gas Model for Multicomponent Diffusion

Evaluation Methodologies for Dense Gas Dispersion Models

Gas permeation models, for perovskite

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Kinetic Molecular Theory A Model for Gases

Kinetic model for gas-solid non-catalytic reaction

Mathematical Models for Gas-Liquid-Solid Reactors

Model for Membrane Separation of a Gas Mixture

Model for complex gas-phase reactions

Models for Transfer at a Gas-Liquid Interface

Models for the packed-bubble-column gas-liquid reactors

Pore Model for Membrane Gas Transport

Solution-Diffusion Model for Single Gas Transport

Solution-Diffusion Model for the Transport of Binary Gas Mixtures

The Kinetic-Molecular Theory A Model for Gas Behavior

Two-Equation Model for Gas Adsorption

Two-Film Mass-Transfer Model for Gas-Liquid Systems

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