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A sub-micron-sized polyethylenimine(PEI)-modified polystyrene/Fe 3 O 4 /chitosan magnetic composite (PS/Fe 3 O 4 /CS-PEI) was developed as a novel adsorbent for the removal of Cu(II) ions from aqueous solutions. The PS/Fe 3 O 4 /CS-PEI microspheres with a diameter of ∼300 nm can be highly monodisperse and conveniently separated from suspensions by a magnet due to their excellent magnetism. When the PS/Fe 3 O 4 /CS-PEI microspheres were used as an absorbent for the absorption of Cu(II) ions, the adsorption isotherms and adsorption kinetics well fitted the Langmuir model and the pseudo-second-order model, respectively. The maximum adsorption capacity was about 204.6 mg g −1 , which was higher than those of other chitosan adsorbents reported recently. The adsorption was considerably fast, reaching the equilibrium within 15 min. In addition, the adsorbed Cu(II) ions could be effectively desorbed using 0.1 mol L −1 NaOH solution, and the regeneration study proved that the composite microspheres could be repeatedly utilized without significant capacity loss after six cycles. All the results demonstrated that the synthesized sub-micron-sized magnetic PS/Fe 3 O 4 /CS-PEI composites can be used as an ideal adsorbent of Cu(II) ions for environmental cleanup applications.

The solubility of two erlotinib hydrochloride polymorphs (form A and form B) in methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, and methyl isobutyl ketone from 273.15 to 323.15 K were determined by means of high-performance liquid chromatography (HPLC). The modified Apelblat equation and the Buchowski–Ksiazczak λh equation were used to correlate the experimental solubility data. The results showed that the solubility of both forms generally increased with the temperature and at a given temperature decreased with the increase of the carbon number of alcohols; furthermore, methyl isobutyl ketone showed the largest solubility in the studied ketones. Meanwhile form A had a higher solubility than form B which demonstrated that form A was the metastable form. Furthermore, both models mentioned above gave satisfactory correlation results, in which the modified Apelblat equation worked better than the Buchowski–Ksiazczak λh equation.

In our work, the triethylenetetramine-modified hollow Fe3O4/SiO2/chitosan magnetic nanocomposites (Fe3O4/SiO2/CS-TETA) were successfully fabricated by a facile way. Due to hollow and porous nano structure, as well as modification by TETA, the Fe3O4/SiO2/CS-TETA nanocomposites have more and stronger adsorption sites for chromium ions. The adsorption capacity of Cr(VI) ions was as high as 254.6 mg g−1 and the adsorption equilibrium time was within 15 min, which are much superior than most similar adsorbents. In addition, the good magnetic recovery and reuse of the hollow Fe3O4/SiO2/CS-TETA nanocomposites gives them excellent practical application capabilities for removal of Cr(VI) ions from wastewater. Thus, hollow Fe3O4/SiO2/CS-TETA nanocomposites can be used as an ideal adsorbent for the recycle removal of Cr(VI) ions from wastewater.

In order to develop more suitable anticorrosive coatings for hydraulic engineering metal structures, studies were carried out on the preparation and electrochemical properties of water-borne inorganic zinc-rich coatings in this paper. Through effective regulation of the type and dosage of silicate and zinc powder, modified water-borne inorganic zinc-rich coatings were prepared. Coupled with the enhanced anti-corrosion and electrochemical protection property, this modified new coating possesses a broader application prospect in hydraulic engineering metal structures.