C‐rich graphitic carbonitride materials (CN_x) with a large range of compositions have been prepared thanks to the self‐assembly, in different ratios, of melamine (M) and a panel of polycarboxylic acids (A) such as oxalic, tartaric and citric acid. The thermal conversion of the formed adducts (MA_y), led to CN_x phases, with x ranging from 0.66 to 1.4 (x=1.33 for g‐C₃N₄ for comparison). The properties of these materials were examined by different techniques (XRD, Raman spectroscopy, TEM, TGA, XPS and DRIFT). It appears that the increase in the C content is associated with the disappearance of the long‐range order of heptazine units and an increase in the sub‐nanometer carbon‐rich cluster size within the graphitic g‐C₃N₄ structure. This trend is followed by a significant increase in the interlayer spacing and a lower proportion of N=C−N bonds compared to C=C bonds. The thermal stability under an inert atmosphere of these phases and their UV‐Visible absorbance properties were also investigated.

The study is focused on monitoring the influence of selected parameters on the zeta potential values of titanium dioxide nanoparticles. The influence of pH, temperature, ionic strength, and mass content of titanium dioxide in the suspension was assessed. More than a thousand samples were measured by combining these variables. On the basis of results, the model of artificial neural network was proposed and tested. The authors have rich experiences with neural networks applications and this case shows that the neural network model works with a very high prediction success rate of zeta potential. Clearly, pH has the greatest effect on zeta potential values. The influence of other variables is not so significant. However, it can be said that increasing temperature results in an increase in the value of the zeta potential of titanium dioxide nanoparticles. The ionic force affects the zeta potential depending on the pH; in the vicinity of the isoelectric point, its effect is negligible. The effect of the mass content of titanium dioxide in the suspension is absolutely minor.