The structural and morphological parameters of nanopowders (Taunit-M and thermally expanded graphite (TEG)) are established; carbon nanotubes and graphene sheets are identified. The maximum sizes of nanocrystals do not exceed 5 and 10 nm in the [0001] and [ 101̅0 ] directions. Multiwalled nanotubes with the diameter of 10 nm form flat tapes up to 40 nm in an X-ray amorphous carbon matrix. Rotation of graphene sheets in TEG is from 3° to 4°. Full dislocations with the Burgers vector b = 1/2 [ 101̅0 ] are revealed within graphene sheets.

The reaction of N -trimethylsilylacetamides with ambifunctional silane ClCH 2 SiMeCl 2 afforded N -[dichloro(methyl)silylmethyl]- N -methylacetamide, N -[dichloro(methyl)-silylmethyl]- N -(4-methylphenyl)acetamide, and N -[dichloro(methyl)silylmethyl]- N -(4-chlorophenyl)acetamide. Multinuclear NMR spectroscopy showed that these compounds exist in solution as (O—Si)-chelates with an intramolecular C=O→Si dative bond. According to the X-ray diffraction analysis, the length of the C=O→Si dative bond in N -[dichloro(methyl)silylmethyl]- N -methylacetamide is 1.903(1) Å. In the crystal, this compound exists as a benzene solvate. The layered structure is stabilized by short Cl⋯H 3 C(O) and Cl⋯H 3 CN contacts between the axial chlorine atom and the hydrogen atoms of the amide group of the adjacent molecule (2.869 and 2.826 Å, respectively). Besides, the hydrogen atoms of the Me 3 Si group are involved in π-stacking interactions with the benzene molecule ( l = 2.889 Å).

Acetoacetanilide reacts with trimethylchlorosilane (reagent ratio 1:1) in a hexane medium at room temperature to form N -phenyl-3-[(trimethylsilyl)oxy]but-2-enamide as a mixture of E and Z isomers in the ratio 11 : 0.1. Multinuclear NMR monitoring showed that at room temperature the ratio of isomers E : Z gradually changes in a CDCl 3 solution, reaching 3.1 : 9.6 after 14 days. A possible mechanism of the isomerization is discussed.

Chloromethyl(dimethyl)pentafluorophenoxysilane (ClCH2SiMe2OC6F5) reacted with trimethylsilyl derivatives of N-methylacetamide, N-phenylacetamide, and N-methylbenzamide to form the corresponding (O-Si) chelates with a pentacoordinated silicon atom: N-[dimethyl(pentafluorophenoxy)silyl]methyl-N-methylacetamide, N-[dimethyl-(pentafluorophenoxy)silyl]methyl-N-phenylacetamide, and N-[dimethyl(pentafluorophenoxy)silyl]methyl-N-methylbenzamide. The structure of products was confirmed by multinuclear NMR spectroscopy, the mechanism of their formation was discussed.

The reaction of N-trimethylsilyl-N-methylacetamide with polyfunctional silanes, namely methyl(chloromethyl)alkoxychlorosilanes and (chloromethyl)difluoro(isopropoxy)silane, was studied. Structure of the synthesized (O–Si)-chelates was studied by the quantum chemistry methods. Data on the apicophilicity of fluorine and chlorine atoms in these compounds were obtained.

New representatives of (O-Si)-chelate compounds, N -(fluorosilyl)methyl derivatives of N -methylacetamide, N -methylbenzamide, N -phenylacetamide, and N -phenylbenzamide, were synthesized using different synthetic approaches. An analysis of the structures of these compounds established by 29 Si NMR spectroscopy and X-ray diffraction and the published data showed that the degree of C-O→Si dative interaction decreases when the methyl group on the nitrogen atom is replaced by a phenyl substituent. The replacement of the methyl substituent at the carbonyl group by a phenyl substituent has a less significant effect but also leads to a decrease in the C-O→Si dative bonding. The X-ray diffraction study of N -[(difluoromethylsilyl)methyl]- N -phenylbenzamide at 100 and 293 K provided evidence that the C-O→Si dative bond length changes inversely to changes in the equatorial bond lengths of the C-O→SiC 2 F 2 coordination unit with a change in the temperature.

Previously unknown 2,2′-bis(silyloxy)azobenzenes containing a carbon functional group on the silicon atom have been synthesized. The reaction of 2,2′-dihydroxyazobenzene with chlorosilanes R1R2(ClCH2)SiCl (R1 = R2 = Me; R1 = OBu-t, R2 = Me) in the presence of triethylamine led to the formation of the corresponding 2,2′-bis[(chloromethyl)diorganylsilyloxy]azobenzenes which underwent intramolecular cyclization on prolonged storage at room temperature to produce more stable cyclic azobenzenes with an N=N→Si transannular dative bond, 6,6-dimethyldibenzo- and 6-(chloromethyl)-6-methyldibenzo[d,h][1,3,6,7,2]dioxadiazasilonines. A probable mechanism of the process is discussed.

The first representatives of cyclic azobenzene-siloxane hybrid compounds, namely, 2,4-dimethyl-2,4-diorganyl-1,3,5-trioxa-8,9-diaza-2,4-disiladibenzo[ f,j ]cycloundecanes and 6,6,8,8,10,10-hexamethyl-1,3,5,7-tetraoxa-10,11-diaza-2,4,6-trisiladibenzo[ h,l ]cyclotridecane, were synthesized.

The reaction of dichloromethylphenylsilane with tert-butanol in the presence of a hydrogen chloride acceptor gave tert-butoxychloromethylphenylsilane. The product is stable at room temperature for a week, undergoing disproportionation upon more prolonged storage. Its reaction with 2-substituted ethanols XCH2CH2OH (X = Cl, MeNH, PhCH2N, PhN) in the presence of bases gives the corresponding polyfunctional silanes MePhSi(OBut)(OCH2CH2X). Alkylation of such N-substituted derivatives with (chloromethyl)triethoxysilane results in polyfunctional α-silyl amines MePhSi(OBut)OCH2CH2N(R)CH2Si(OEt)3 (R = Me, Bn). The structures of all synthesized compounds were confirmed by IR and multinuclear NMR spectroscopy.

In this work, the composition, morphology and mechanical properties of the surface of semiconductor thermoelectric legs before and after the pulsed photon treatment were studied. The n-type (Bi2Te3-Bi2Se3) and the p-type (Bi2Te3-Sb2Te3) legs fabricated by a hot pressing method were treated using a special technique, including mechanical polishing, pulsed photon irradiation with xenon lamps and electrochemical etching. The pulsed photon treatment significantly enhanced mechanical properties and adhesion hardness of the thermoelectric legs. The mechanical polishing followed by the pulsed photon treatment increased the adhesion of the barrier and commutation Mo/Ni layers three- and twofold for the n-type and p-type legs, respectively. The pulsed photon treatment stimulated local recrystallization of the surface defect layer up to 100-200 nm in-depth under an effective temperature of about 800 K in the near-surface layer of branches. Besides, the pulsed photon treatment increased the surface hardness of the Bi2Te3-Bi2Se3 system by 1.2 times. The surface modification of thermoelectric legs through the pulsed photon treatment did not decline the barrier properties of the Mo-layer in Ni-Mo-Bi2Te3 + Bi2Se3 heterostructures.

The phase and structural transformations that Pd–Ru(7 at %) solid solution thin films undergo during thermal oxidation in oxygen in the temperature range 570–1070 K are studied by transmission electron microscopy, high-energy electron diffraction, and reflection high-energy electron diffraction. With increasing oxidation temperature, the phase composition is found to change in the order: Pd–Ru(7 at %) solid solution → Pd–Ru(7 at %) + PdO + RuO2 → PdO + RuO2 → PdO–RuO2 solid solution. We show that the complete oxidation of Pd–Ru(7 at.%) thin films to form single-phase films of the PdO–RuO2 solid solution takes place at a temperature of 100 K higher compared to pure palladium films. The resistance sensor response of the prepared PdO−RuO2 oxide films to ozone in air is studied for the first time. The results suggest that this is a promising material for use in gas-sensing applications.

We carry out comparative studies of the phase composition, morphology, and hardness of semiconductor legs based on the n-type solid solution Bi2Te3−Bi2Se3, obtained by hot pressing, after surface modification (mechanical processing and pulsed photon treatment (PPT) with incoherent light). Using shear tests, we determine the adhesion of switching and barrier Mo–Ni layers on the modified surfaces of semiconductor legs. Pulsed photon treatment stimulates local recrystallization of the imperfect layer near the surface of samples of the Bi2Te3−Bi2Se3 solid solution to a depth of 100−200 nm, which increases the hardness of the surface layers. It is shown that the mechanical polishing and subsequent pulsed photon treatment of thermoelectric legs increases the adhesion of the switching and barrier Mo–Ni layers by 3–4 times, which can contribute to the efficient and stable operation of a thermoelectric generator battery.

1,3-Dimethoxy- 1,3-dimethyl- 1,3-diphenyl- and 1,3-dimethoxy- 1,3-tetraphenyldisiloxanes were synthesized. Their structures were confirmed by IR and NMR spectroscopy. The structure of 1,3-dimethoxy-1,3-tetraphenyldisiloxane was determined by X-ray diffraction.

By the methods of transmission electron microscopy, high energy electron diffraction, atomic force microscopy, and Auger electron spectroscopy, the article studies the phase composition, orientation, substructure, and morphology of the films formed during pulsed photon treatment (PPT) by radiation of xenon lamps of silicon (111) Si substrates in an atmosphere of methane. We have established that in the range of the energy density of radiation (Ep) supplied to the substrate with a thickness of 0.45 μm for 3 s from 269 to 284 J cm-2 the oriented nanocrystalline films are formed on both surfaces of the substrates both from the irradiated and non-irradiated side β-SiC thickness of about 150 nm. In this case, the synthesis of films on the irradiated side is carried out with the possible participation of photon activation of processes and on the reverse side – only by thermal activation (short-term heat treatment (SHT). With an increase in the energy density of radiation in β-SiC films, the average subgrain size on the irradiated side is shown to increase from 4.2 nm (Ep = 269 J ·cm-2) to 7.9 nm (Ep = 284 J ·cm-2) and on the non-irradiated side 3.9 to 7.0 nm respectively. The surface roughness of the β-SiC surface proceeds consequentially on the irradiated side from 19 nm (Ep = 269 J ·cm-2) to 60 nm (Ep = 284 J ·cm-2) and on the non-irradiated side from 11 nm to 56 nm respectively. Based on the temperature dependences of the average grain size and roughness, we have estimated the apparent activation energies of the processes. The activation energy of subgrain β-SiC growth is practically independent of the activation method and is 1.3 eV. The activation energy for the evolution of roughness is 2.5 eV at a PPT and 3.5 eV at a SHT.