Doxycycline Degradation by the Oxidative Fenton Process
Table 3
(a) Results of the analysis of variance applied to residual doxycycline concentration data collected at the end of the Fenton process under different operating conditions. (b) Results obtained by the quadratic model.
(a)
Sum of squares
Degrees of freedom
Mean square
-calc.
value
(L)
218.87
1
218.868
2.68
0.133
(Q)
0.003
1
0.002
0.00
0.998
(L)
775.21
1
775.219
9.50
0.012
(Q)
1253.19
1
1253.195
15.36
0.003
(L)
279.76
1
279.760
3.43
0.094
(Q)
118.65
1
118.652
1.46
0.255
27.38
1
27.380
0.33
0.575
56.18
1
56.180
0.69
0.426
4.805
1
4.805
0.06
0.813
(b)
Variation source
Sum of squares
Degrees of freedom
Mean square
-calc.
value
Regression
2688.80
9
298.756
3.65
0.0279
Residues
817.95
10
81.795
Lack of fit
814.87
5
162.975
265.14
0.000005
Pure error
3.07
5
0.615
Total
3506.75
19
% explained variation ()
76.675
Tabled 9; 10; 0.05
3.02
L = linear regression; Q = quadratic regression; = coded values of ; = coded values of ; = coded values of .