Fabrication and Response Surface Methodology for the Adsorption of Nickel Ferrite-Graphene Oxide Nanocomposite for the Removal of Methylene Blue from Water

Table 6

Estimated coefficient of variables.

Factor	Estimated coefficient	Standard deviation
	269.68	2.77
	9.75	1.83
	1.60	1.83
	44.29	1.83
	7.05	2.40
	2.28	2.40
	17.94	2.40
^2	2.63	1.79
^2	1.70	1.79
^2	-7.91	1.79