Transport properties of gases

L. H. Chen, Thermodynamic and Transport Properties of Gases, Eiquids and Solids, McGraw-HiU Book Co., Inc., New York, 1959, pp. 358—369. 

Of a special astronomical interest is the absorption due to pairs of H2 molecules which is an important opacity source in the atmospheres of various types of cool stars, such as late stars, low-mass stars, brown dwarfs, certain white dwarfs, population III stars, etc., and in the atmospheres of the outer planets. In short absorption of infrared or visible radiation by molecular complexes is important in dense, essentially neutral atmospheres composed of non-polar gases such as hydrogen. For a treatment of such atmospheres, the absorption of pairs like H-He, H2-He, H2-H2, etc., must be known. Furthermore, it has been pointed out that for technical applications, for example in gas-core nuclear rockets, a knowledge of induced spectra is required for estimates of heat transfer [307, 308]. The transport properties of gases at high temperatures depend on collisional induction. Collision-induced absorption may be an important loss mechanism in gas lasers. Non-linear interactions of a supermolecular nature become important at high laser powers, especially at high gas densities. 

The transport properties of gases arise from collisional interactions between molecules. The rigorous mathematical treatment of transport properties is very complex [35,60,103, 115,178], However, the underlying physical basis for the viscosity, thermal conductivity, and diffusion coefficient can be readily understood. This section gives a model to derive... 

There are two major drawbacks of the gas-phase processes first, the limited heat-transport properties of gases make adequate temperature control impossible for the exothermic hydrogenation reactions [4] and, secondly, the use of gas-phase processes is limited to small volatile molecules. 

The Van Deemter equation (Chapter 2) shows how diffusion and transfer processes affected HETP. Applications of GC to the measurement of transport properties of gases have shown to be... 

Todd, B., Young, J.B., 2002. Thermodynamic and transport properties of gases for use in SOFC modeling. Journal of Power Sources 110, 186-200. 

Table B2 Collision integrals for predicting transport properties of gases at low densities ...

In this section we shall be concerned with a molecular theory of the transport properties of gases. The molecules of a gas collide with each other frequently, and the velocity of a given molecule is usually changed by each collision that the molecule undergoes. However, when a one-component gas is in thermal and statistical equilibrium, there is a definite distribution of molecular velocities—the well-known Maxwellian distribution. Figure 1 shows how the molecular velocities are distributed in such a gas. This distribution is isotropic (the same in all directions) and can be characterized by a root-mean-square (rm speed u, which is given by... 

R. B. Bird, J. O. Hirschfelder, and C. F. Curtiss Theoretical Calculation of the Equation of State and Transport Properties of Gases and Liquids, Trans. ASME, 76 1011 (1954). 

Supercritical fluids exhibit physicochemical properties between those of liquids and gases. These properties favor their introduction into different matrices and also analyte solubility. In addition, SFs exhibit transport properties of gases (high diffusivity). Mass transfer is rapid with SFs. 

APPLICATIONS OF THE KIHARA POTENTIAL TO THERMODYNAMIC AND TRANSPORT PROPERTIES OF GASES. FROM ADVANCES IN THERMOPHYSICAL PROPERTIES AT EXTREME TEMPERATURES AND PRESSURES. 

THE INFLUENCE OF A MAGNETIC FIELD ON THE TRANSPORT PROPERTIES OF GASES OF PLLYATOMIC MOLECULES. PART II. THERMAL CONDUCTIVITY. 

Table 21.1.3. Transport properties of gases, liquids, and supercritical fluids...

Table B2 Collision Integrals for Predicting Transport Properties of Gases at Low Densities...

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