Coupled flow

Another interesting, but rather complex system, which couples flow injection analysis, EC and GC has been recently reported (47). This system allows the determination of the total amount of potentially carcinogenic polycyclic aromatic compounds (PACs) in bitumen and bitumen fumes. This system could also be used for the analysis of specific PACs in other residual products. 

Figure 5.67 Correlating function of coupled flow rate and quality effects on CHF, F(X, G), where F(X, G) = [(0.1484 - 1.596T + 0.1729X X )G/106 + 1.037], (From Tong, 1968a. Copyright 1968 by American Nuclear Society, LaGrange Park, IL. Reprinted with permission.)...

Coupling Flow Cytometry with Image Analysis—Assessing the Role... 

COUPLING FLOW CYTOMETRY WITH IMAGE ANALYSIS-ASSESSING THE ROLE OF MACROPHAGES IN TISSUE INJURY... 

The use of the difference operator in Eq. (73) implies that the concentration gradient across the sample is linear. However, due to coupled flow processes, the... 

TNC.65. 1. Prigogine and R. Lefever, On the spatio-temporal evolution of cellular tissues, in Biological Structures and Coupled Flows, A. Oplatka and M. Balaban, eds.. Academic Press, New York, 1983, pp. 3-26. 

Figure 5.24 Example fiber-optic-coupled flow cell sample system.

It should be noted that Figs 2.12-2.16 do not include every possible type of configuration, as shown in subsequent chapters. Rather, they provide an overview of the wide variety of on-line coupled flow-through sensors and continuous unsegmented-flow analytical configurations. 

Figure 2.17 compares the different ways of regenerating flow-through sensors with the normal procedure for probe sensors the probe is successively immersed in the sample and buffer solution and removed from it prior to immersion into the next sample, which hinders automated functioning unless a robot station is lised (Fig. 2.17.A). On the other hand, on-line coupled flow-through sensors in continuous configurations lend themselves readily to convenient, automated regeneration.

By coupling flow field-flow fractionation (flow FFF) to ICP-MS it is possible to investigate trace metals bound to various size fractions of colloidal and particulate materials.55 This technique is employed for environmental applications,55-57 for example to study trace metals associated with sediments. FFF-ICP-MS is an ideal technique for obtaining information on particle size distribution and depth profiles in sediment cores in addition to the metal concentrations (e.g., of Cu, Fe, Mn, Pb, Sr, Ti and Zn with core depths ranging from 0-40 cm).55 Contaminated river sediments at various depths have been investigated by a combination of selective extraction and FFF-ICP-MS as described by Siripinyanond et al,55... 

Carriers, like enzymes, show saturation and stereospecificity for their substrates. Transport via these systems may be passive or active. Primary active transport is driven by ATP or electron-transfer reactions secondary active transport, by coupled flow of two solutes, one of which (often H+ or Na+) flows down its electrochemical gradient as the other is pulled up its gradient. 

Finite element formulations for large-scale, coupled flows in adjacent porous and open fluid domains (with A.G. Salinger and J.J. Derby). Int. J. Num. Meth. Fluids 18,1185-1209 (1994). 

Figure 3.29 Example fibre-optic-coupled flow cell detail.

Figure 5.3 Single coupling flow injection system for sample preparation introduction in CE system [39].

Figure 11.14 Geometry and collocation points for the coupled flow-heat transfer problem RF method solution, with grid-like and randomly arranged collocation points.

Figure 11.15 Comparison between the temperature field predicted using RFM with arranged and random collocation points and by FDM for the coupled flow-heat transfer problem.

Figures 11.15 and 11.16 compare the temperature and velocity profiles, respectively, for the steady-state, fully developed flow of the coupled flow-heat transfer pressure driven slit flow problem, using RFM and FDM. The agreement between the two solutions is excellent.

O.A. Estrada, I.D. Lopez-Gomez, and T.A. Osswald. Modeling the non-newtonian calendering process using a coupled flow and heat transfer radial basis functions collocation method. Journal of Polymer Technology, 2005. 

There are different ways of describing the coupled flow problem in streaming potentials, one is by at Onsager s reciprocity relations and the other is by... 

The description of coupled flow and transport phenomena is usually based on non-equilibrium thermodynamics [2], Application of this theory leads to a set of linear equations, relating all thermodynamical fluxes Jj to all thermodynamical forces Xj in a system ... 

Abstract A permeameter was developed for measurement of coupled flow phenomena in clayey materials. Results are presented on streaming potentials in a Na-bentonite induced by hydraulic flow of electrolyte solutions. Transport coefficients are derived from the experiments, assuming the theory of irreversible thermodynamics to be applicable. Hydraulic and electro-osmotic conductivities are consistent with data reported elsewhere. However the electrical conductivity of the clay is substantially lower. This is ascribed to the high compaction of the clay resulting in overlap of double layers... 

Keywords coupled flow, irreversible thermodynamics, bentonite, clay, streaming potential... 

Abstract In this contribution, the coupled flow of liquids and gases in capillary thermoelastic porous materials is investigated by using a continuum mechanical model based on the Theory of Porous Media. The movement of the phases is influenced by the capillarity forces, the relative permeability, the temperature and the given boundary conditions. In the examined porous body, the capillary effect is caused by the intermolecular forces of cohesion and adhesion of the constituents involved. The treatment of the capillary problem, based on thermomechanical investigations, yields the result that the capillarity force is a volume interaction force. Moreover, the friction interaction forces caused by the motion of the constituents are included in the mechanical model. The relative permeability depends on the saturation of the porous body which is considered in the mechanical model. In order to describe the thermo-elastic behaviour, the balance equation of energy for the mixture must be taken into account. The aim of this investigation is to provide with a numerical simulation of the behavior of liquid and gas phases in a thermo-elastic porous body. 

While under physiological conditions, the driver molecule is usually Na+ (in Na+-coupled flows), the driven solute should enhance the flow of the normal driver and bring about its uphill movement, if the experimental conditions are appropriately modified. For example, if the energy from the Na+ electrochemical gradient, i.e., AjINa+ = 0, but AjIsoluteis large the outward (downhill) movement of solute from the cell will drive cell Na+ uphill into the medium. 

As discussed in Section II, the excited-state dynamics of polyatomic molecules is dictated by the coupled flow of both charge and energy within the molecule. As such, a probe technique that is sensitive to both nuclear (vibrational) and electronic configuration is required in order to elucidate the mechanisms of such processes. Photoelectron spectroscopy provides such a technique,... 

H. J. Salacinski, P. G. Riby, S. J. Haswell, Coupled flow-injection analysis-flame atomic absorption spectrometry for the quantitative determination of aluminum in beverages and waters incorporating on-line cation exchange, Anal. Chim. Acta, 269 (1992), 1-7. 

The effect of backward defect scattering is more subtle. There are coupled flow equations for t-1, gt, and Kp [see Eq. (12) for its definition]. The main effect of the disorder is to generate an effective electron backward scattering proportional to t 1 that subtracts to gt and accordingly acts to decrease Kp. There are three possible sets of fixed points. 

When there is a two-component flow with coupling, then we have two flows Ji X and Jl 2 for each lump /, and a matrix of Rljk coefficients. The bond graph is modified additively to accommodate the two coupled flows, and the two-component coefficients lijk, mijh and riJk are expressed in terms of Rj]k (Figure 14.4)... 

It is in the treatment of such interacting transport processes, or coupled flows, that the methods of near-equilibrium thermodynamics yield a clear understanding of such phenomena, but only from a macroscopic or phenomenological point of view. These methods, as relevant to the present discussion, can be summarized with the following series of statements ... 

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