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 7

Analysis of variance for Total Dry Weight (TDW) using CCD.

Source	Sum of squares	Degree of freedom	Mean square	-value	value
Model	3606.26	5	721.25	2.10	0.1799
	14.57	1	14.57	0.042	0.8426
	1063.90	1	1063.90	3.10	0.1216
	405.02	1	405.02	1.18	0.3132
	1069.03	1	1069.03	3.12	0.1208
	355.18	1	355.18	1.04	0.3427
Residual	2400.72	7	342.96
Lack-of-Fit	2400.27	3	800.09	7054.21	<0.0001
Pure error	0.45	4	0.11
Cor total	6006.98	12

-Squared = 0.6003; Adj -Squared = 0.3149; Pred -Squared = −2.3503; Adeq Precision = 5.643.
is amount of f-MWCNTs.
is functionalization reflux time.