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Friedel-Crafts alkylation reaction of vinyltri-methoxysilane with styrene was performed in the pres-ence of anhydrous AlCl3. Alkoxy(4-vinylphenethyl)silane has been obtained. The synthesized products were identified by 1H, 13C, COSY NMR, and FTIR spectroscopy. Calculations using the quantum-chemical non-empirical density functional theory (DFT) method for the reaction between vinyltrimethoxysilane and styrene performed for ortho-, meta- and para-positions were discussed. For the theoretical modeling an online prediction program "Priroda 04: A quantum-chemical program suite" was used. Composite materials based on wood sawdust with various dispersion qualities and synthesized trimethoxysilylated styrene as a binding and reinforcing agent with degrees of silylation (5 %), in the presence of various organic/inorganic additives, fire retardants, and antioxidants, have been developed at different temperatures and pressures via hot press method or extrusion. The physico-mechanical properties of composites have been investigated.

The new possibilities of preparing the ethyl 4-nitrobenzoate by esterification of 4-nitrobenzoic acid (4-NBA) with ethanol under argon at 80˚C are shown; particularly, over catalysts: on micrometric (4.8 -7.0 μm) or ultradispersed crystallites (290 -480 nm) of hydrogen forms of nanoporous natural zeolites H-CL, H-MOR, H-HEU-M, H-PHI and under irradiation of the reaction mixture with ultrasound (US, 37 kHz, 330 W, 2 h) or microwaves (MW, 2450 MHz, 300 W, 2 h). Ultradispersed crystallites of zeolite catalysts were prepared from hydrogen forms of parent natural zeolites by their treatment with US or MW. In the esterification, the synergism of the actions of catalysts and MW or US was revealed; wherein on the ultradispersed best catalysts H-HEU-M and H-MOR conversion of 4-NBA and yield of ethyl 4-nitrobenzoate reached up to 70% and 67%, respectively. GC/MS, FTIR, NMR methods were used in the study.

some machine learning algorithms for sex identification based on linear mandibular measurements derived from CT scans .