Low Temperature Densities from (218 to 364) K and up to 50 MPa in Pressure and Surface Tension for Trihexyl(tetradecyl)phosphonium Bis(trifluoromethylsulfonyl)imide and Dicyanamide and 1-Hexyl-3-methylimidazolium Hexafluorophosphate Klomfar, J.; Součková, M.; Pátek, J.; Journal of Chemical & Engineering Data 2014, 59, 2263-2274