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We study the generalized Besov spaces and the spaces defined by the conditions imposed on local oscillations of locally summable functions (in the paper, these spaces are called generalized Campanato spaces). [ABSTRACT FROM AUTHOR]

We report here on functionalization of surgical meshes (PVDF) with novel hybrid material, consisting of Ag@crown nanoparticles, embedded on CaCO3/PEG nanosheets. Nanosheets of PEG 4000 with average thickness of 25 nm enclosing CaCO3 nanoparticles with average sizes of 150 nm were applied for sustained release of Ag@crown nanoparticles that in turn serve as antibacterial agent. The characterization of obtained hybrid nanostructures was carried out by microscopic and spectroscopic methods. Microbiological tests confirmed the effectiveness of hybrid material, consisting of Ag@crown nanoparticles, embedded in CaCO3/PEG nanostructure, as an antibacterial coating for surgical meshes. This coating was applied to insure antibacterial properties of meshes against microorganism colonization, in order to significantly improve their action in typical applications. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) nanosheets were functionalized with Schiff base and reduced Schiff base. Covalent and non-covalent functionalized GO nanostructures have been tested for the removal of pesticides with different chemical structures and properties (e.g., Epoxiconazole, Dimethomorph, Cyprodinil, Chlorothalonil, Acetochlor, Trifluralin) from aqueous solutions. The structure and morphology characteristics of the prepared structures were analyzed using techniques such as solid-state nuclear magnetic resonance (SSNMR), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Results of the experiments showed that, although the non-covalent functionalization did not affect the adsorption properties of GO much, the covalent functionalization increased the adsorption capacity of GO against the mentioned pesticides.

This study is devoted to the synthesis of a 40-membered macroheterocycle with its further nanostructuring by magnetite nanoparticles. The mentioned macroheterocycle was synthesized by the [2+2] cyclocondensation of the oxygen-containing diamine with an aromatic dialdehyde in a non-catalytic medium and with no work-up procedure. The structure of the obtained macroheterocycle was studied by 1 H and 13 C nuclear magnetic resonance spectroscopy and matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Furthermore, the nanosupramolecular complex of macroheterocycles with magnetite nanoparticles was obtained and investigated by Fourier-transform infrared and ultraviolet-visible spectroscopy methods. Shifts in the infrared spectra of the nanosupramolecular complex indicate the interaction through metal-aromatic ring non-covalent bonding. The shift is also observed for the C-O-C stretching band of ether bonds. The loading rate of macroheterocycles on magnetite nanoparticles was 18.6%. The morphology of the ensemble was studied by transmission electron microscopy, which confirmed the synthesis of nanospherical particles with a diameter range of 10-20 nm. Powder X-ray diffraction analysis showed patterns of cubic Fe 3 O 4 nanoparticles with a crystallite size equal to 9.1 nm. The macroheterocycle and its nanosupramolecular complex were tested against Klebsiella pneumoniae , Pseudomonas aeruginosa and Staphylococcus aureus . The results have shown that the created complex has shown 64 times better activity against Staphylococcus aureus in comparison with the individual macroheterocycle and 32 times better activity in comparison with the pristine antibiotic Ampicillin as a control. In addition, computational analysis of the macroheterocycle was performed at the B3LYP/6-31G level in water. Molecular docking analyses for the macroheterocycle revealed Penicillin-binding protein PBP2a (5M18) from the transpeptidase family as a target protein in Staphylococcus aureus .