code: def water(target, temperature='pore.temperature', salinity='pore.salinity'):
      r
      T = target[temperature]
      if salinity in target.keys():
          S = target[salinity]
      else:
          S = 0
      T68 = 1.00024*T  # convert from T_90 to T_68
      SP = S/1.00472  # convert from S to S_P
      k_sw = 0.001*(10**(sp.log10(240+0.0002*SP) +
                         0.434*(2.3-(343.5+0.037*SP)/T68) *
                         ((1-T68/(647.3+0.03*SP)))**(1/3)))
      value = k_sw
      return value
docs: r"""
      Calculates thermal conductivity of pure water or seawater at atmospheric
      pressure using the correlation given by Jamieson and Tudhope. Values at
      temperature higher  the normal boiling temperature are calculated at the
      saturation pressure.
  
      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.
  
      temperature : string
          The dictionary key containing the temperature values.  Temperature must
          be in Kelvin for this emperical equation to work
  
      salinity : string
          The dictionary key containing the salinity values.  Salinity must be
          expressed in g of salt per kg of solution (ppt).
  
      Returns
      -------
      The thermal conductivity of water/seawater in [W/m.K]
  
      Notes
      -----
      T must be in K, and S in g of salt per kg of phase, or ppt (parts per
      thousand)
  
      VALIDITY: 273 < T < 453 K; 0 < S < 160 g/kg;
      ACCURACY: 3 %
  
      References
      ----------
      D. T. Jamieson, and J. S. Tudhope, Desalination, 8, 393-401, 1970.