IG O (KJmol-1 ), IS O (Jmol-1 K-1 ) and IH O (KJmol-1 ) are respective Gibbs free energy, entropy and enthalpy changes (Table-3), T is a temperature (K) and R is a

gas constant (8.314Jmol - K - ).

Where [C.sub.d] is flow coefficient obtained from flow test, A is orifice effective area, R is

gas constant, [P.sub.0] is upstream pressure of orifice, [T.sub.0] is upstream air temperature of orifice, k is air specific heat ratio of orifice, [P.sub.im] is pressure of intake manifold, [V.sub.d] is displacement volume, [R.sub.cyl] is

gas constant cylinder, [T.sub.im].

with [C.sub.o] and [C.sub.e] as initial and equilibrium concentrations in mol/[cm.sup.3], R, the

gas constant, and T, the solution temperature in K.

where P is pressure, [M.sub.i] is molecular mass, T is temperature and R is the universal

gas constant.

where A and B are the material constant, [sigma] is the average normal stress (MPa), [theta] is the average shear stress (MPa), Q is the activation energy (J/mol), R is the

gas constant (8.3 [mol.sup.-1] [K.sup.-1]), T is the absolute temperature (K), and n and m are the stress exponent under tensile and shear loads, respectively.

where [q.sub.e] (mmol [g.sup.-1]) is the amount of metal ions adsorbed, Qdr (mmol [g.sup.-1]) is the maximum adsorption capacity of metal ions, KDR ([mol.sup.2]/[kJ.sup.2]) is the Dubinin-Radushkevich isotherm constant, Ce (mol [dm.sup.-3]) is the equilibrium concentration of metal ions, R is the

gas constant (8.314 J/mol K), and T (K) is absolute temperature in Kelvin.

where R is the universal

gas constant (8.3144 J [mol.sup.1] [K.sup.1]), T is the absolute temperature, [E.sub.a] is the activation energy of diffusion, and [D.sub.0] is a diffusion constant.

* the value for the universal molar

gas constant from The Committee on Data for Science and Technology (CODATA) standard by Mohr and Taylor (2005),

Where R represents universal

gas constant, T represents absolute temperature and k represents formation constant of the systems.

where p is the absolute pressure, V the volume of the system, R the universal

gas constant, and T the absolute temperature.

where p is the atmospheric pressure, T is the thermodynamic temperature, [x.sub.v] is the mole fraction of water vapor, [M.sub.a] is the molar mass of dry air, [M.sub.v] is the molar mass of water, [R.sub.g] is the molar

gas constant, and Z is the compressibility factor.

The free energy of formation ([DELTA]F) is equal to the free energy of formation at equilibrium ([DELTA][F.sup.o]) minus the multipicand of the

gas constant (R), the temperature (T) and the natural log of the equilibrium constant (K), as shown in the equation: