Том 57, № 5 (2023)

Phototransformations of 6-nitro-8-methoxy-substituted indoline spiropyran in acetonitrile have been studied by laser kinetic spectroscopy (laser photolysis) with single- and double-pulse excitation. The role of the triplet state in the kinetics of photocoloration of spiropyran has been revealed. It has been shown that photochromic transformations of spiropyran involve unstable trans-isomers (conformers) of the open merocyanine form of spiropyran. Data on the transformation kinetics of the trans-isomers are presented.

This study is devoted to the effect of complete deuteration of the ethylene glycol carbon skeleton on the formation of its radiation-induced free-radical transformations products in deaerated aqueous solutions at pH 7.00 ± 0.10 and a dose rate of 0.064 ± 0.002 Gy/s. It has been established that the chain process of fragmentation of carbon-centered ethylene glycol radicals (∙CH(OH)CH2OH) plays an important role in the formation of acetaldehyde. The replacement of protium atoms located at carbon atoms by deuterium decreased the radiation-chemical yield of acetaldehyde in aqueous 1 M solutions of diols by a factor of 8. The results of this study indicate that the use of deuterium exchange at the carbon skeleton of organic molecules is a promising way for increasing their resistance to radiation-induced free radical fragmentation processes.

Coatings of aluminoborosilicate fabric have been obtained by deposition from solutions of radiation-synthesized tetrafluoroethylene telomers. The resulting coatings were characterized by IR spectroscopy. By the sessile drop method, it has been established that the surface of the coatings is hydrophobic with a water contact angle of 140°. The effect of gamma-radiation on the molecular structure of coatings has been examined using IR spectroscopy. It has been shown that irradiation of the studied samples in air results in the formation of terminal COOH groups, which worsen the hydrophobicity of the samples. Irradiation in vacuum does not affect the hydrophobic properties of telomeric coatings

The electron-beam treatment of an aqueous solution of the azo dye Ponceau 4R (0.02 g/dm3) at a dose of 1.5 kGy in air led to the complete elimination of color and genotoxicity. The addition of OH radicals to the system of conjugated bonds of the dye (the formation of OH adducts) was a key radiolytic process, which led to the elimination of side groups with lower binding energies

A process for fabricating Al-doped β-Ga2O3 thin films of the (AlxGa1−x)2O3 composition by plasma-enhanced chemical vapor deposition has been studied for the first time. High-purity gallium metal, aluminum iodide (AlI3), and high-purity oxygen were used as precursors. Low-temperature plasma at a reduced pressure (0.01 torr) was the initiator of chemical transformations between the reactants. The plasmaenhanced deposition process was studied by optical emission spectroscopy in the range of 180–1100 nm. The obtained thin films of the (AlxGa1−x)2O3 system with the amount of the Al2O3 phase up to 20% were studied by various analytical methods.

Experimental data presented in the literature on the depth of processing of polymer films using low-temperature plasma are considered. Changes in the chemical composition and structure along the depth of the samples have been studied using the modern experimental techniques of X-ray photoelectron spectroscopy, secondary ion mass spectrometry, and transmission electron microscopy; precision etching was carried
out with an Ar+2500 cluster beam; and the pit depth was measured by profilometry. It has been found that the thickness of the modified layer is ≤50 nm and depends relatively little on the polymer nature.

The object of the study is ultrafine bismuth barium borate glasses 20Bi2O3–хBaO–(80−х)B2O3, х = 5, 10, or 20 mol % BaO, synthesized using a unique version of the sol–gel method and holding promise for fabricating functional crystalline glass ceramics, in particular, based on yttrium aluminum garnet. A DSC analysis of the obtained charge material with 0.5 μm spherical particles revealed their glassy state at temperatures
of 450–475°C. The presence of glass in particles of such a small size allows the use of the so-called cluster approximation in a quantum-chemical study of the geometric and electronic structure of glasses by the DFT/UB3LYP/LanL2DZ method. Calculated IR absorption spectra are compared with the experimental spectra of the obtained dispersed samples.

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