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This study presents the results of surface modification of zirconium dioxide (ZrO2) nanoparticles by 3-(trimethoxysilyl) propyl methacrylate silane coupling agent by assessing some characteristics and properties of modified ZrO2 nanoparticles by infrared spectroscopy, thermogravimetric analysis, size distribution, zeta potential, and field emission scanning electron microscopy methods. The modified and unmodified ZrO2 nanoparticles have been used as nanoadditives for organic coatings based on acrylic emulsion resin. The abrasion resistance of acrylic coating was evaluated according to ASTM E968-15. The obtained results show that ZrO2 nanoparticles were functionalized successfully with 3-(trimethoxysilyl) propyl methacrylate silane. The modified ZrO2 nanoparticles exhibit a positive effectiveness in the enhancement of the abrasion resistance of acrylic resin coating compared to unmodified ZrO2 nanoparticles.

This paper presents some characteristics, properties, and morphology of TiO2 nanoparticles (nano-TiO2) modified with various contents of 3-(trimethoxysilyl)propyl methacrylate (TMSPM) coupling agent. The treatment process was carried out in ethanol solvent at 50oC using ammonia as a catalyst for hydrolysis reaction of silane to silanol. Infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy, field emission scanning electron microscopy, dynamic light scattering, ultraviolet-visible spectroscopy, and X-ray diffraction methods were used for determination of the characteristics, properties of nano-TiO2 before and after treatment. In addition, the contact angle and grafting efficiency of TMSPM on the surface of TiO2 nanoparticles was also evaluated. The obtained results confirmed that TMSPM was grafted to the TiO2 nanoparticles, the agglomeration of nano-TiO2 was decreased, and surface of TiO2 nanoparticles became hydrophobic after modification by TMSPM.

A new megastigmane glycoside, gangeticoside (1), and three known compounds leonuriside A (2), methyl benzoate 2-O-β-D-glucopyranoside (3), and tortoside A (4) were isolated from the aerial part of Desmodium gangeticum. Their structures were determined by 1D and 2D NMR spectra. The isolated compounds were evaluated for their inhibitory effect on NO production in LPS-stimulated RAW264.7 cells. Among them, compounds 1, 2, and 3 exhibited strong effect with the IC50 values of 22.3, 15.6, 7.3 μM, respectively.

In this study, the relationship between heavy metals (HMs) concentrations in soils and several weeds including Cyclosorus parasiticus, Dicranopteris linearis, Pityrogramma calomelanos, and Pteris vittata in three mining sites (Cam Gia (Thai Nguyen city), Tan Long (Dong Hy district), and Ha Thuong (Dai Tu district)) in Thai Nguyen province, Vietnam, have been investigated. The levels of HMs varied among soil origins and showed the contaminations of As, Cu, and Pb in soil samples collected in Dong Hy and Dai Tu districts. In addition, the HM distribution and cocontamination phenomena in different soils significantly affected the HM residues and transportation abilities into different species as well as tissues. Moreover, based on the analysis of bioaccumulation factor (BF) and translocation factor (TF), C. parasiticus and D. linearis were found potentially for phytoextraction by roots, while P. calomelanos and P. vittata were suitable for hyperaccumulation in shoots and leaves. Consequently, the strongest antioxidant property by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide anion (SRSA) radical scavenging assays were demonstrated in the methanol root extracts of C. parasiticus and P. vittata, respectively. In conclusion, the correlation among HM in soils and tissues with antioxidant property allows us to hypothesize that the presence of these elements can enhance the antioxidant activity of plant extracts, suggesting to apply the weeds in phytoremediation as well as in phytomedicine.

N-(4-Substituted phenyl)acetamides, which were prepared from acetic anhydride and p-substituted anilines, were utilized as precursors for reactions to Vilsmeier-Haack reagent to form 6-substituted-2-chloroquinoline-3-carbaldehydes 3a–c. Meanwhile, a similar reagent was applied to 1-[1-(4-substituted phenyl)ethylidene]-2-phenylhydrazines as substrates, which were synthesized from phenylhydrazine hydrochloride and p-substituted acetophenones, and 1,3-diarylpyrazole-4-carbaldehydes 3d–f were observed as a result. Reactions between the aldehydes 3a–f and 7-chloro-4-hydrazinylquinoline 2, obtained from reaction of 4,7-dichloroquinoline 1 and hydrazine hydrate, formed six new hydrazone compounds, namely, 4-{2-[(6-substituted-2-chloroquinolin-3-yl)methylidene]hydrazinyl}-7-chloroquinolines 4a–c and 4-(2-{[3-(4-substituted phenyl)-1-phenyl-1H-pyrazol-4-yl]methylene}hydrazinyl)-7-chloroquinolines 4d–f. The chemical structures of all synthesized compounds were elucidated by the analysis of IR, 1H, 13C-NMR, and HRMS spectral data. Additionally, all of the synthesized hydrazones were evaluated in terms of cytotoxic activity against four strains of bacteria and four strains of fungus at several concentrations of substrates. As a result, three of them, 4a–c, possess the good ability as growth inhibitor of Bacillus subtilis and Aspergillus niger at the concentration of 25 μg/mL and 50 μg/mL, respectively, while compound 4e only shows a cytotoxic activity against Aspergillus niger at the concentration of 25 μg/mL.

Different compositions of Co3O4 catalysts on CeO2-ZrO2 solid solution (Ce0.9Zr0.1O2 and Ce0.8Zr0.2O2) have been studied for the oxidation of propylene. The optional amount of Co3O4 active phase on CeO2-ZrO2 support of 30 wt% was found. The mixed Co3O4-CeO2-ZrO2 with the same composition of the optimal supported ones showed approximately the same activity, which was not higher than the activity of the mixed Co3O4-CeO2 catalyst. Catalytic activities of mixed Co3O4-CeO2 with different loading contents supported on high surface area supports (Al2O3, SiO2) were then measured. The optimal composition of active phase was still 30 wt% but the minimum temperature of the highest activity increased to above 300°C due to the inert nature influence of the support.