Variables | Units | Coded & uncoded level of variables | ||||
---|---|---|---|---|---|---|
−α | −1 | 0 | 1 | +α | ||
Temperature, X 1 | °C | 53 | 60 | 70 | 80 | 87 |
Time, X 2 | Min | 66 | 80 | 100 | 120 | 133 |
Solvent ratio, X
3
Ethanol:water | v/v% | 63 | 70 | 80 | 90 | 97 |