References in periodicals archive ?
where [E.sub.a] is activation energy, R the gas constant (8.314 J/mol/ K), T is the temperature in Kelvin, k is adsorption rate constant, and A is frequency factor.
The activation energy value Ea was calculated as the slope of the plot multiply by the gas constant R, and the constant A was an exponential of the intercept.
Nomenclature Variables [C.sub.j,r]: The molar concentration of each reactant or product j in reaction r (-) [D.sub.i]: Diffusion coefficient of component I ([m.sup.2] [s.sup.-1]) h: Enthalpy (kJ [kg.sup.-1]) J: Diffusion flux (mol [m.sup.-2] [s.sup.-1]) [k.sub.f,r]: Forward reaction rate in reaction r (-) [k.sub.b,r]: Backward reaction rate in reaction r (-) M: Relative molecular mass (-) P: Pressure (Pa) q: Heat (kJ) R: Universal gas constant = 8.314 (J [mol.sup.-1] [K.sup.-1]) [R.sub.i]: Net production rate of reaction i (mol [m.sup.-3] [s.sup.-1]) t: Time (s) T: Temperature (K) u: Flowrate (m [s.sup.-1]) [v'.sub.i,r]: The stoichiometric coefficient of reactant i in reaction r (-) [V".sub.i,r]: The stoichiometric coefficient of resultant i in reaction r (-) Y: Mass fraction (%).
where [V.sub.H] and [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] are the partial molar volumes of H in Pd and of [H.sub.2] in [H.sub.2]O, respectively, and R is the gas constant.
The mass of diatomic hydrogen and the molar gas constant given in Table 1 are from the most recent tabulations of such information (9), (10).
Where Z is the pre-exponential constant, Ea is the activation energy of the reaction, R is the universal gas constant and T is the absolute temperature in degrees Kelvin.
where [M.sub.g] is the molecular weight of the gas (kg/mol), R is the universal gas constant (J/K x mol), and T is the absolute temperature (K).
If there is 1 [micro]mol/22.4 [micro]L (a gas constant at standard temperature and pressure) and 1 /[micro]mol C[O.sub.2] has a molecular weight of 44 [micro]g, then the bulk C[O.sub.2] concentration is 707 /[micro]g [L.sup.-1] or 0.707 /[micro]g [cm.sup.-3].
R is the specific gas constant (ft pounds/pound mass/ degree Rankine)