Fluxes description

Flux Description Natural Anthro. This work... 

Since partial molar enthalpies are used in the energy flux description (6), no source term appears in eq. (12). 

Flux Description of flux Flux (moles P X 10 yr ) References and comments... 

Flux description Flux (moles PXlO yr ) Residence time s (yr)... 

Flux Description Kellag Friend, GranatMoller, Ivanov, 1983 etal, 1973 el at, 1984 Natural Anthrop, 1973 1976 Charlson Dobrovolsky, etal, 1994 1992 ... 

Flux Description Kellogg etal. (1972) Friend (1973) Granat etal. (1976) Moller (1984a, b) Ivanov (1983) This work (natural only)... 

Scheme 1 was developed to fit equilibrium results obtained with fluxes. Description of the electrophysiological results (many of which are kinetic and of a higher temporal resolution) requires rate constants of the transitions between states, for example, obtained by single-channel analysis. Such analysis has been carried out on cultured ventricular myocytes and led to the kinetic Scheme 2 where O stands for channels kept open by the coactivator BDF 9145, a state with much increased affinity for veratridine so that the doubly bound state O predominates over O with possible transitions between these states as BDF dissociates and reassociates. O can be distinguished during bursts by its current amplitude as compared with the small (one-quarter) amplitude of veratridine-associated states (Wang et al. 1990 Scheme 2). 

Hammes, G.G., Chang, Y.-C., and Oas, T.G. (2009) Conformational selection or induced fit a flux description of reaction mechanism. Proceedings of the National Academy of Sciences of the United States of America, 106 (33), 13737-13741. 

The tliree conservation laws of mass, momentum and energy play a central role in the hydrodynamic description. For a one-component system, these are the only hydrodynamic variables. The mass density has an interesting feature in the associated continuity equation the mass current (flux) is the momentum density and thus itself is conserved, in the absence of external forces. The mass density p(r,0 satisfies a continuity equation which can be expressed in the fonn (see, for example, the book on fluid mechanics by Landau and Lifshitz, cited in the Furtlier Reading)... 

At very low densities It Is quite easy Co give a theoretical description of thermal transpiration, alnce the classical theory of Knudsen screaming 9] can be extended to account for Che Influence of temperature gradients. For Isothermal flow through a straight capillary of circular cross-section, a well known calculation [9] gives the molar flux per unit cross-sectional area, N, In the form... 

The voltage used for electro dialysis is about 1 V per membrane pair, and the current flux is of the order of 100 A/m of membrane surface. The total power requirement increases with the feedwater salt concentration, amounting to about 10 MW per m product water per 1000 ppm reduction in salinity. About half this power is required for separation and half for pumping. Many plant flow arrangements exist, and their description can be found, along with other details about the process, in References 68 and 69. Many ED plants, as large as 15,000 vsf jd, are in operation, reducing brackish water concentration typically by a factor of 3—4. 

The more general use of Eq, (5-128) is to obtain the set of total interchange areas AS"- which con stitute a complete description of the effect of shape,. size, and emi.s.sivity on radiative flux, independent of the pre.sence or absence of other tran.sfer mechanisms. It may be shown that... 

The resistances, when incorporated into equations descriptive of cross-flow filtration, yield the general expression for the permeate flux for particulate suspensions in cross-flow-electrofiltration systems. 

The low-temperature chemistry evolved from the macroscopic description of a variety of chemical conversions in the condensed phase to microscopic models, merging with the general trend of present-day rate theory to include quantum effects and to work out a consistent quantal description of chemical reactions. Even though for unbound reactant and product states, i.e., for a gas-phase situation, the use of scattering theory allows one to introduce a formally exact concept of the rate constant as expressed via the flux-flux or related correlation functions, the applicability of this formulation to bound potential energy surfaces still remains an open question. 

There are three different approaches to a thermodynamic theory of continuum that can be distinguished. These approaches differ from each other by the fundamental postulates on which the theory is based. All of them are characterized by the same fundamental requirement that the results should be obtained without having recourse to statistical or kinetic theories. None of these approaches is concerned with the atomic structure of the material. Therefore, they represent a pure phenomenological approach. The principal postulates of the first approach, usually called the classical thermodynamics of irreversible processes, are documented. The principle of local state is assumed to be valid. The equation of entropy balance is assumed to involve a term expressing the entropy production which can be represented as a sum of products of fluxes and forces. This term is zero for a state of equilibrium and positive for an irreversible process. The fluxes are function of forces, not necessarily linear. However, the reciprocity relations concern only coefficients of the linear terms of the series expansions. Using methods of this approach, a thermodynamic description of elastic, rheologic and plastic materials was obtained. 

Thus far, the burn-out phenomenon has been discussed mainly in terms of the important system-describing parameters. This approach is preferable, since the system parameters are, in fact, the independent variables and they must uniquely and unequivocally determine the heat flux required to produce burn-out. It can be argued, however, that burn-out, being a local phenomenon, may be described entirely by local parameters of this there can be no dispute. The problem is to find a description of these local parameters that works. Our... 

The present model takes into account how capillary, friction and gravity forces affect the flow development. The parameters which influence the flow mechanism are evaluated. In the frame of the quasi-one-dimensional model the theoretical description of the phenomena is based on the assumption of uniform parameter distribution over the cross-section of the liquid and vapor flows. With this approximation, the mass, thermal and momentum equations for the average parameters are used. These equations allow one to determine the velocity, pressure and temperature distributions along the capillary axis, the shape of the interface surface for various geometrical and regime parameters, as well as the influence of physical properties of the liquid and vapor, micro-channel size, initial temperature of the cooling liquid, wall heat flux and gravity on the flow and heat transfer characteristics. 

This chapter focuses on types of models used to describe the functioning of biogeochemical cycles, i.e., reservoir or box models. Certain fundamental concepts are introduced and some examples are given of applications to biogeochemical cycles. Further examples can be found in the chapters devoted to the various cycles. The chapter also contains a brief discussion of the nature and mathematical description of exchange and transport processes that occur in the oceans and in the atmosphere. This chapter assumes familiarity with the definitions and basic concepts listed in Section 1.5 of the introduction such as reservoir, flux, cycle, etc. 

In contrast to the pre-existing models that merely portrayed membrane potentials, the new generation of models calculated the ion fluxes that give rise to the changes in cell electrical potential. Thus, the new models provided the core foundation for a mechanistic description of cell function. Their concept was applied to cardiac cells by Denis Noble in 1960. 

A complete model for the description of plasma deposition of a-Si H should include the kinetic properties of ion, electron, and neutral fluxes towards the substrate and walls. The particle-in-cell/Monte Carlo (PIC/MC) model is known to provide a suitable way to study the electron and ion kinetics. Essentially, the method consists in the simulation of a (limited) number of computer particles, each of which represents a large number of physical particles (ions and electrons). The movement of the particles is simply calculated from Newton s laws of motion. Within the PIC method the movement of the particles and the evolution of the electric field are followed in finite time steps. In each calculation cycle, first the forces on each particle due to the electric field are determined. Then the... 

The fluid model is a description of the RF discharge in terms of averaged quantities [268, 269]. Balance equations for particle, momentum, and/or energy density are solved consistently with the Poisson equation for the electric field. Fluxes described by drift and diffusion terms may replace the momentum balance. In most cases, for the electrons both the particle density and the energy are incorporated, whereas for the ions only the densities are calculated. If the balance equation for the averaged electron energy is incorporated, the electron transport coefficients and the ionization, attachment, and excitation rates can be handled as functions of the electron temperature instead of the local electric field. 

There are various parameters and assumptions defining radionuclide behavior that are frequently part of model descriptions that require constraints. While these must generally be determined for each particular site, laboratory experiments must also be conducted to further define the range of possibilities and the operation of particular mechanisms. These include the reversibility of adsorption, the relative rates of radionuclide leaching, the rates of irreversible incorporation of sorbed nuclides, and the rates of precipitation when concentrations are above Th or U mineral solubility limits. A key issue is whether the recoil rates of radionuclides can be clearly related to the release rates of Rn the models are most useful for providing precise values for parameters such as retardation factors, and many values rely on a reliable value for the recoil fluxes, and this is always obtained from Rn groundwater activities. These values are only as well constrained as this assumption, which therefore must be bolstered by clearer evidence. 

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