Exchange coefficients

From Tolmin s theory and experimental data (e.g., Reichardtthe relationship between velocity profile and temperature profile in the jet cross-section can be expressed using an overall turbulent Prandtl number Pr = v /a, where Vf is a turbulent momentum exchange coefficient and a, is a turbulent heat exchange coefficient ... 

Convective heat exchange coefficient A complicated factor involving the surface ge... 

Teflon no tube fouling. cross-exchange. coefficient. 2.0-4.0... 

Campion et ai have calculated a value for the exchange coefficient (10 °C, zero ionic strength) of 1 x 10 l.mole sec from the observed rate coefficients for the reactions... 

For the following we assume that the atmospheric variations in C02 and in its carbon isotopic composition are entirely due to atmospheric system disturbances, such as the input of 14C-free C02 from fossil C02 production, and deviations from the average rate of 14C production by cosmic radiation. The system dynamics, i.e., the exchange coefficients and the eddy diffusivity are kept constant. We approximate the fossil C02 input p(t) by... 

To prepare for our calculation, we save these reactions and exchange coefficients in a dataset CaMgNaJx.dat . We take the sediment s cation exchange capacity to be 4 meq (100 g) 1, or 4 x 10-5 eq g 1. We further assume a porosity of 30%, so that per kg of pore fluid, there is about 2300 cm3 of sediment. 

Gas exchange occurs (l) between bubbles and clads, characterized by exchange coefficient Kbc (equation 23.3-13), and (ii) betwoen clouds and emulsion, characterized by Kce (equation 23.3-14). 

We illustrate the development of the model equations for a network of two parallel reactions, A -> B, and A - C, with kt and representing the rate constants for the first and second reactions, respectively. Continuity equations must be written for two of the three species. Furthermore, exchange coefficients (Kbc and Kce) must be determined for each species chosen (here, A and B). 

FIGURE 3.4 Measured effective surface oxygen exchange coefficient of the LSM/YSZ composites as a function of the LSM content. (From Ji, Y. et al., Solid State Ionics, 176 937-943, 2005. With permission.)... 

Oxygen Diffusion Coefficient (D ), Oxygen Surface Exchange Coefficient (Ar), and Oxygen Ionic Conductivity (tr,) of LaMn03-Based Oxides Measured by SIMS Technique... 

Summer ME, Miller WE Cation exchange capacity and exchange coefficients. In Bartels JM (ed.), Methods of Soil Analysis. Part 3. Chemical Methods. Madison, WI Soil Science Society of America 1996, pp. 1201-1229. 

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