DESIGN AND OPTIMIZATION FOR HAZARDOUS JAROSITE WASTE RECYCLING IN ENVIRONMENTALLY SUITABLE COMPOSITE PRODUCTS USING RESPONSE SURFACE METHODOLOGY - Management of Hazardous Residues Containing Cd - page 71

Table 11. Sequential model sum of squares for response shrinkage

Source Sum of

Squares

DF Mean

Square

F Value Proc>F

Mean 5298.57 1 5298.57

Linear 1415.24 2 707.62 17.25 0.0004

Quadratic 374.98 3 124.99 13.13 0.0019

Special Cubic 53.02 1 53.02 16.06 0.0051

Cubic 20.50 3 6.83 10.45 0.0231

Residual 2.62 4 0.65 --- --

Total 7164.92 14 511.78 --- --

Table 12. Sequential model sum of squares for response density

Source

Sum of Squares DF Mean Square F Value Proc>F

Mean 39.48 1 39.48

Linear 0.20 2 0.098 18.88 0.0003

Quadratic 0.052 3 0.017 26.85 0.0002

Special
Cubic

8.162E-005 1 8.162E-005 0.11 0.7469

Cubic 1.768E-003 3 5.893E-004 0.71 0.5927

Residual 3.300E-003 4 8.250E-004

Total 39.73 14 2.84

Table 13. Sequential model sum of squares for response Cadmium
Source Prob > F Sum of

Square

DF Mean

Squares

F Value

Mean 2.50 1 2.50

Linear 0.41 2 0.21 32.43 < 0.0001 Suggested

Quadratic 0.035 3 0.012 2.71 0.1155

Special
Cubic

7.145E-005 1 7.145E-

005

0.014 0.9080

Cubic 0.035 3 0.012 376.19 < 0.0001 Suggested

Residual 1.230E-004 4 3.075E-

005

Total 2.98 14 0.21