Kinetic isotope fractionation between water vapor and liquid water or ice depends on the ratio of the diffusivities of the isotopic species in air, but there is disagreement as to the values of these ratios and limited information about their temperature dependence. We use state-of-the-art ...
Viscosity and Thermal Conductivity of Air and Diffusivity of Water Vapor in Air Carefully chosen numerical values for the viscosity and thermal conductivity of air and diffusivity of water vapor in air are tabulated for temperatures from 20C to +4OC and for a pressure of 1000 mb. A summary of...
A handful selection of the contours of transversal slices is shown in Fig. 3 for fresh and pretreated samples, air-dried at 50 °C. As shown in this figure, the osmotic dehydration pretreatment caused an important sample size reduction; thus, they exhibit a lower initial size in comparison ...
as well asthermal diffusivityofair,nitrogenandpropane. Water thermal diffusivity at atmospheric pressure, temperature given as °C or °F: . Water thermal diffusivity at 1, 10 and 100 bara (14.5, 145 and 1450 psia) pressure, temperature given as °C or °F: . Thermal diffusivity of water ...
as well asthermal diffusivityofnitrogen,propaneandwater. Air thermal diffusivity at 1 bara pressure, temperature given as °C or °F: Air thermal diffusivity at varying temperatures and constant pressures, SI and Imperial units: Air thermal diffusivity at atmospheric pressure, given in SI and Imperi...
The water vapor feedback on ITCZ shifts is shown to be dominated by changes in the cross-equatorial asymmetry of the relative humidity of subtropical dry zones, with additional contributions by the changes in mixing ratio that occur at fixed relative humidity and by the meridional shift of the ...
A gas diffusion layer for use in fuel cells comprises a fiber and non-fiber material in a ratio such that the water vapor diffusion transport resistance is greater than 0.8 s/cm mea
A diffusion medium for use in a PEM fuel cell comprising a thin perforated layer having variable size and frequency of perforation patterns incorporated into a microporous layer on a first side of a porous substrate layer, wherein the diffusion medium is adapted to improve water management and pe...
We have determined the isotope effects of (17)O and (18)O substitution of (16)O in H(2)O on molecular diffusivities of water vapor in air by the use of evaporation experiments. The derived diffusion fractionation coefficients (17)alpha(diff) and (18)alpha(diff) are 1.0146 +/- 0.0002 ...
Water vapor-air effective diffusivity is one of the tranport properties needed for design, modeling, and simulation of many food processes. The effective diffusivity and a tissue structure factor are defined and determined by a method based on steady state counter-current diffusion flux under zero ...