Effects of the surface physico-chemical properties and the surface textures on the initial colonization and the attached growth in algal biofilm

Table 3 Estimates of coefficients of the variables in the second-order polynomial regression with different Wenzel’s numbers

Coefficient	Variables	r < 1.60		r ≥ 1.60
Coefficient	Variables	Estimate	p value	Estimate	p value
\( \alpha_{0} \)	Constant	156.2	0.08	104.6	0.15
\( \alpha_{1} \)	\( \theta_{\text{te}} \)	−2.2	0.43	19.4	<0.05
\( \alpha_{2} \)	r	275.3	<0.05	65.4	0.13
\( \alpha_{12} \)	\( \theta_{\text{te}} \times r \)	3.7	<0.05	1.7	0.69
\( \alpha_{11} \)	\( \theta_{\text{te}}^{2} \)	−0.1	0.38	0.7	<0.05
\( \alpha_{22} \)	r ²	122.6	<0.05	n.a.^a	n.a.
Regression coefficient (R ²)		0.57		0.75
p value		<0.001		<0.001

The equation \( Y = \alpha_{0} + \alpha_{1} \theta_{\text{te}} + \alpha_{2} r + \alpha_{12} \theta_{\text{te}} r + \alpha_{11} \theta_{\text{te}}^{2} + \alpha_{22} r^{2} \) was used for correlation, where Y is cell attachment (g m⁻²), r is the Wenzel’ number (dimensionless), and \( \theta_{\text{te}} \) is tetradecane contact angle (°)
^aThe estimate was not available

ISSN: 2731-3654