code: def fuller(target, MA, MB, vA, vB, temperature='pore.temperature',
             pressure='pore.pressure'):
      r
  
      T = target[temperature]
      P = target[pressure]
      MAB = 2*(1.0/MA+1.0/MB)**(-1)
      MAB = MAB*1e3
      P = P*1e-5
      value = 0.00143*T**1.75/(P*(MAB**0.5)*(vA**(1./3)+vB**(1./3))**2)*1e-4
      return value
docs: r"""
      Uses Fuller model to estimate diffusion coefficient for gases from first
      principles at conditions of interest
  
      Parameters
      ----------
      target : OpenPNM Object
          The object for which these values are being calculated.  This
          controls the length of the calculated array, and also provides
          access to other necessary thermofluid properties.
  
      MA : float, array_like
          Molecular weight of component A [kg/mol]
  
      MB : float, array_like
          Molecular weight of component B [kg/mol]
  
      vA:  float, array_like
          Sum of atomic diffusion volumes for component A
  
      vB:  float, array_like
          Sum of atomic diffusion volumes for component B
  
      pressure : string
          The dictionary key containing the pressure values in Pascals (Pa)
  
      temperature : string
          The dictionary key containing the temperature values in Kelvin (K)