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Table 2 Estimated coefficients and P -values for the response surface models

From: Biorefining of wheat straw: accounting for the distribution of mineral elements in pretreated biomass by an extended pretreatment-severity equation

Factors Whole modelP-valuea   Intercept Temperature pH Time Temperature × pH Temperature × time pH × time
Xylose 2.876 × 10-6 Coef. 3.521 -0.017 0.038 -9.56 × 10-3 - - -
P-valueb 1.13 × 10-6 1.71 × 10-6 5.57 × 10-5 0.125 - - -
Arabinose 3.589 × 10-6 Coef. 0.217 -3.12 × 10-4 0.423 9.97 × 10-3 -2.13 × 10-3 - -
P-value 0.701 0.919 5.83 × 10-4 0.038 1.01 × 10-3 - -
Phosphorus 8.009 × 10-5 Coef. 1.331 -6.47 × 10-3 0.058 0.010 - - -
P-value 0.014 0.019 1.55 × 10-5 0.213 - - -
Magnesium 2.165 × 10-5 Coef. -0.908 3.47 × 10-3 0.467 0.017 -1.92 × 10-3 - 4.13 × 10-3
P-value 0.130 0.249 4.25 × 10-4 0.098 4.22 × 10-4 - 0.017
Calcium 3.33 × 10-4 Coef. -0.869 1.25 × 10-3 0.488 0.035 -1.66 × 10-3 - -7.21 × 10-3
P-value 0.396 0.810 0.010 0.064 0.060 - 0.019
Potassium 1.801 × 10-4 Coef. 2.51 × 10-2 -2.38 × 10-4 5.36 × 10-2 3.25 × 10-3 -2.15 × 10-4 - -5.99 × 10-4
P-value 0.782 0.615 3.65 × 10-3 0.059 0.014 - 0.028
Zinc 1.594 × 10-3 Coef. 1.683 -7.36 × 10-3 0.052 6.67 × 10-3 - - -
P-value 0.018 0.037 3.97 × 10-4 0.519 - - -
Manganese 4.552 × 10-4 Coef. 1.481 -0.011 0.187 0.029 - - 6.654 × 10-3
P-value 0.065 6.32 × 10-3 0.018 0.245 - - 0.092
  1. Coef., coefficient.
  2. aWhole model P-values are given in the top row. These were calculated by comparing the models to their respective null models using F statistics. High P-values (P > 0.05) indicate no dependency on the model factors. Non-significant models (glucose, lignin, silicon, iron, aluminum, copper) are not shown.
  3. bP-values for each factor indicate the statistical significance of this factor in the model, with low values indicating high significance. Non-significant interactions terms (P > 0.1) were removed from the model by single-term backwards model reduction.