[GuHCl] and [Urea] Calculator
Buffer Refractive Index	Sample Refractive Index	Warn me if above solubility (RT)
[GuHCl] C = 57.147*(sample-buffer) + 38.68*(sample-buffer)^2 - 91.6*(sample-buffer)^3   Nozaki, Y
[Urea] C = 117.66*(sample-buffer) + 29.753*(sample-buffer)^2 + 185.56*(sample-buffer)^3   Warren, J. R. & Gordon, J. A.