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The production of low-cost ceramic membranes from natural materials has attracted more and more attention in recent years, as it allows them to reduce their cost while maintaining their advantages. The aim of this study was the synthesis of ceramic membrane supports from kaolin of Ukrainian origin and their characterization. The choice of such a raw material as kaolin was dictated by its characteristics, which were investigated by X-ray and chemical analysis, the nitrogen adsorption/desorption method and thermogravimetric analysis. Ceramic membrane supports were prepared by dry pressing method followed by sintering at 950 °C. The phase composition, morphological structure and structural-adsorption characteristics of the synthesized supports has been established. The effect of the content of boric acid on the electrical resistance of the membrane support has been studied. The ceramic supports after modification of silver demonstrated bactericidal and antifungal effects on Gram-negative (Escherichia coli) and Candida albicans wound pathogens. [ABSTRACT FROM AUTHOR]

The new molecular nickel(II) complex, namely, {4-bromo-2-[({N′-[(2-oxidobenzylidene)amino]carbamimidoyl}imino)methyl]phenolato}nickel(II) N,N-dimethylformamide solvate monohydrate, [Ni(C15H11BrN4O2)]·C3H7NO·H2O, (I), crystallizes in the triclinic space group P\overline{1} with one molecule per asymmetric unit. The guanidine ligand is a product of Schiff base condensation between aminoguanidine, salicylaldehyde and 5-bromosalicylaldehyde templated by Ni²+ ions. The chelating ligand molecule is deprotonated at the phenol O atoms and coordinates the metal centre through the two azomethine N and two phenolate O atoms in a cis-NiN2O2 square-planar configuration [average(Ni--N/O) = 1.8489 Å, cis angles in the range 83.08 (5)-95.35 (5)°, trans angles of 177.80 (5) and 178.29 (5)°]. The complex molecule adopts an almost planar conformation. In the crystal, a complicated hydrogen-bonded network is formed through N--H...N/O and O--H...O intermolecular interactions. Complex (I) was also characterized by FT-IR and ¹H NMR spectroscopy. It undergoes an NiII ↔ NiIII redox reaction at E1/2 = +0.295 V (vs Ag/AgCl) in methanol solution. In a thin film with a free surface, complex (I) shows a fast photoelectric response upon exposure to visible light with a maximum photovoltage of ∼178 mV. [ABSTRACT FROM AUTHOR]

Extracts from the blackcurrant and apricot pomaces were obtained by ultrasound-assisted extraction. Characterization by LC-MS and HPLC methods were performed and total phenolic compounds (TPC), total flavonoid compounds (TFC) and antioxidant activity were assayed. LC-MC and HPLC analysis indicated the presence of phenolic compounds, hydroxycinnamic acids and flavonoids. Various experimental models including iron (III) reducing capacity, total antioxidant capacity, DPPH radical scavenging activity and ABTS•+ radical cation scavenging assay were used for characterization of antioxidant activity of extracts. The blackcurrant and apricot pomaces extracts were tested using cyclic voltammetry (CV). [ABSTRACT FROM AUTHOR]

The new mol-ecular nickel(II) complex, namely, {4-bromo-2-[({ N '-[(2-oxidobenzylidene)amino]carbamimidoyl}imino)methyl]phenolato}nickel(II) N , N -di-methyl-formamide solvate monohydrate, [Ni(C 15 H 11 BrN 4 O 2 )]·C 3 H 7 NO·H 2 O, (I), crystallizes in the triclinic space group P with one mol-ecule per asymmetric unit. The guanidine ligand is a product of Schiff base condensation between amino-guanidine, salicyl-aldehyde and 5-bromo-salicyl-aldehyde templated by Ni 2+ ions. The chelating ligand mol-ecule is deprotonated at the phenol O atoms and coordinates the metal centre through the two azomethine N and two phenolate O atoms in a cis -NiN 2 O 2 square-planar configuration [average(Ni-N/O) = 1.8489 Å, cis angles in the range 83.08 (5)-95.35 (5)°, trans angles of 177.80 (5) and 178.29 (5)°]. The complex mol-ecule adopts an almost planar conformation. In the crystal, a complicated hydrogen-bonded network is formed through N-H⋯N/O and O-H⋯O inter-molecular inter-actions. Complex (I) was also characterized by FT-IR and 1 H NMR spectroscopy. It undergoes an Ni II ↔ Ni III redox reaction at E 1/2 = +0.295 V ( vs Ag/AgCl) in methanol solution. In a thin film with a free surface, complex (I) shows a fast photoelectric response upon exposure to visible light with a maximum photovoltage of ∼178 mV., (© Vassilyeva et al. 2022.)