Application of Response Surface Methodology for Optimization of Urea Grafted Multiwalled Carbon Nanotubes in Enhancing Nitrogen Use Efficiency and Nitrogen Uptake by Paddy Plants

Table 6

Analysis of variance for N uptake using CCD.

Source	Sum of squares	Degree of freedom	Mean square	-value	value
Model	93968.46	5	18793.69	5.18	0.0263
	34088.30	1	34088.30	9.39	0.0182
	30984.95	1	30984.95	8.54	0.0223
	3576.64	1	3576.64	0.99	0.3539
	15960.55	1	15960.55	4.40	0.0742
	19780.29	1	19780.29	5.45	0.0522
Residual	25401.24	7	3628.75
Lack-of-Fit	24231.77	3	8077.26	27.63	0.0039
Pure error	1169.47	4	292.37
Cor total		12

-Squared = 0.7872; Adj -Squared = 0.6352; Pred -Squared = −2.1426; Adeq Precision = 8.519.
is amount of f-MWCNTs.
is functionalization reflux time.