Measurement and Correlation of High-Pressure Densities and Atmospheric Viscosities of Ionic Liquids: 1-Butyl-1-methylpyrrolidinium Bis(trifluoromethylsulfonyl)imide), 1-Allyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide, 1-Ethyl-3-methylimidazolium Tetracyanoborate, and 1-Hexyl-3-methylimidazolium Tetracyanoborate Hiraga, Y.; Hagiwara, S.; Sato, Y.; Smith, R.L.; Journal of Chemical & Engineering Data 2018, 63, 972-980