KEM RA-620, Operation Manual

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8. Technical Information
RA-620/RA-600 41
About refractive index of water (nD)
The following list shows relative refractive index (nD) of water at various temperatures
(Celsius) with light source of sodium Na-D line.
Temp.
(  C)
RI
(nD)
Temp.
(  C)
RI
(nD)
Temp.
(  C)
RI
(nD)
Temp.
(  C)
RI
(nD)
5 1.33388 25 1.33250 45 1.32985 65 1.32628
6 1.33385 26 1.33240 46 1.32969 66 1.32609
7 1.33382 27 1.33229 47 1.32953 67 1.32589
8 1.33378 28 1.33217 48 1.32937 68 1.32568
9 1.33373 29 1.33206 49 1.32920 69 1.32548
10 1.33369 30 1.33194 50 1.32904 70 1.32527
11 1.33363 31 1.33182 51 1.32887 71 1.32507
12 1.33358 32 1.33170 52 1.32870 72 1.32486
13 1.33352 33 1.33157 53 1.32852 73 1.32464
14 1.33345 34 1.33144 54 1.32835 74 1.32443
15 1.33338 35 1.33131 55 1.32817 75 1.32422
16 1.33331 36 1.33117 56 1.32799
17 1.33324 37 1.33104 57 1.32781
18 1.33316 38 1.33090 58 1.32762
19 1.33307 39 1.33075 59 1.32744
20 1.33299 40 1.33061 60 1.32725
21 1.33290 41 1.33046 61 1.32706
22 1.33280 42 1.33031 62 1.32687
23 1.33271 43 1.33016 63 1.32668
24 1.33261 44 1.33001 64 1.32648
Allan H. Harvey, John S. Gallagher, J. M.H. Levelt Senger "Revised Formulation for the
Refractive Index of Water and Steam as a Function of Wavelength, Temperature, and
Density" J. Phys. Chem. Ref. Data Vol.27, No.4 pp.761-774 (1998)
About Brix %
Brix % means mass concentration % of sucrose; however, it is often used as
concentration % of soluble solid matter contained in aqueous solution. Soluble solid
means all substances including sugar, salt, protein, etc. that are soluble in water.
Though you can obtain the actual concentration with sucrose solution, you may not
necessarily obtain the concentration of sucrose solution when the solution contains other
types of soluble solid matter.