TABLE 93.-Copper-levulose equivalents according to the Jackson and Mathews modification of the Nyns selective method for levulose-—Continued TABLE 94.-Ratio of levulose to total sugar from the Lane and Eynon titration and Nyns "apparent" levulose Example illustrating the use of table 94.-Assume that a solution of levulose and dextrose gave a Lane and Eynon titer of 25.89 ml and that 20 ml of the same solution precipitated 247.3 mg of copper by the modified Nyns method. The original solution then contained by table 93 (100×71.7)/20=358.5 mg of apparent levulose per 100 ml. Then TXI 25.89 X 358.5 =92.8. Referring to the values tabulated below we find opposite this product and under T-25 the true ratio of levulose to total sugar to be 71.5 percent. The Lane and Eynon factor is 125.7, and the total sugar per 100 ml is 125.7/25.89=485.5 mg, of which 71.5 percent (347.1 mg) is levulose and 138.4 mg is dextrose. TABLE 94.-Ratio of levulose to total sugar from the Lane and Eynon titration and Nyns "apparent" levulose-Continued TABLE 95.-Ratio of levulose to total sugar from the Lane and Eynon titration and the polarization by the Mathews formula [The table gives the percentage ratio (R) of levulose to total reducing sugar calculated from the Lane and Eynon titration and the direct polarization at 20° C. P is the polarization in °S; T is the corrected Lane and Eynon titer; D is the number of volumes to which one volume of the solution polarized was diluted for the titration; and ƒ is the factor used for correcting the percentage ratio found in the table. This correction is given by ƒX D/T and is to be added algebraically. The table can be used when the polarization is made at a temperature other than 20° C by using the temperature coefficient, AR/At°. When the temperature is 1°, the correction is (AR/Ať°) (t° — 20°), and is to be added algebraically to the ratio.] |