Transport properties overview

In this chapter we will review the recent investigations of the structure of both the a and P subunit, and the function of gastric H,K-ATPase. We will proceed from a brief overview of the tissue distribution to a successive discussion of structure, kinetics, transport properties, lipid dependency, solubilization and reconstitution, and inhibitors of H,K-ATPase that may label functionally important domains of the enzyme. 

This chapter gives an overview of the fundamental physical basis for the thermodynamic (enthalpy, entropy and heat capacity) properties of chemical species. Other chapters discuss chemical kinetics and transport properties (viscosity, thermal conductivity, and diffusion coefficients) in a similar spirit. 

The effects of molecular order on the gas transport mechanism in polymers are examined. Generally, orientation and crystallization of polymers improves the barrier properties of the material as a result of the increased packing efficiency of the polymer chains. Liquid crystal polymers (LCP) have a unique morphology with a high degree of molecular order. These relatively new materials have been found to exhibit excellent barrier properties. An overview of the solution and diffusion processes of small penetrants in oriented amorphous and semicrystalline polymers is followed by a closer examination of the transport properties of LCP s. 

This chapter treated, the fixed-bed reactor, a tubular reactor packed with, catalyst pellets. We started with a general overview of the transport and reactio.n events that take place in. the fixed-bed reactor transport by convection in the fluid diffusion inside the catalyst pores. and adsorption, reaction and desorption on the catalyst surface. We summarized the transport properties of the catalyst particles, and described bulk and Knudsen diffusion phenomena. 

An overview of the physics of glassy polymers and the relationships between molecular mechanisms and macroscopic physical, mechanical and transport properties of polymer glasses is presented. The importance of local translational and/or rotational motions of molecular segments in the glass is discussed in terms of the implications for thermodynamic descriptions of the glass (configurational states and energy surfaces) as well as history dependent properties such as expansivity, refractive index, gas permeability, and viscoelastic mechanical behaviour. 

This brief overview of the electrical transport properties in doped conducting polymers highlights the following points ... 

To use a new material for a specific application, it is vital to understand and characterize its transport properties such as thermal transport, mass transport, and electrical transport. With the advent of large and fast massively parallel computers, it is now possible to devise new molecular modeling (MM) methods that can reliably compute transport properties for complex materials from the bottom up. In this chapter, we provide an overview of some commonly used techniques to compute transport coefficients for materials, using classical molecular dynamics (MD). We apply MD to two interesting physical situations as illustrative examples. 

A brief overview of the electrical transport properties of systems from the metallic and insulating regimes, for both oriented and unoriented samples, are also discussed. The suggested models are quite appropriate in understanding the etq)erimental results. Nevertheless, more work is needed to sort out how the structural and morphological features influence the transport properties. 

Hermans L. J. F. (1992). Overview on experimental data from Senftleben-Beenakker effects, in Status and Future Developments in the Study of Transport Properties, eds. W.A. Wakeham, A.S. Dickinson, F.R.W. McCourt V. Vesovic, pp. 155-174. Dordrecht Kluwer. 

Thermophysical properties - thermodynamic and transport properties - of pure fluids and mixtures are of essential importance for apparatus design and energy and process technology. A safe, ecologically harmless and economical use of substances can be achieved only if their thermophysical properties are known to a sufficiently high degree of accuracy. Practical experience, however, shows that it is often costly in terms of time and labor to get reliable information. In addition, even for experts it is sometimes difficult to overview and critically assess all available data of interest. Inevitably, unreliable and inconsistent data are often used. 

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