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The reactions of dichlorodimethylsilane or 1,3-dichlorotetramethyldisiloxane with bis(trimethylsilyl) ester of terephthalic acid (1:1 molar ratio, 20°C, 72–144 h) gave 69–97% yields of previously unknown 27- and 22-membered cyclic organosilicon esters of terephthalic acid, respectively. The molecular structures of 22-membered ester 4,4,6,6,12,12,14,14-octamethyl-3,5,7,11,13,15-hexaoxa-4,6,12,14-tetrasila-1,9(1,4)-dibenzacyclohexadecaphane-2,8,10,16-tetraone and trimethylsilyl ester of terephthalic acid were studied by X-ray structural analysis.

Crystal and molecular structures of two silatranes, 1-iodomethyl-3-methyl- and 1-iodomethyl-3,7,10-trimethyl-2,8,9-trioxa-5-aza-1-silabicyclo[3.3.3]undecanes, were determined by X-ray analysis. Comparison of their structural and geometrical characteristics with those of other silatranes shows that the presence of methyl substituents β-positioned to nitrogen atoms increases the length of the dative Si←N bond, whereas the introduction of iodine into the axial position of the silatrane slightly decreases the length of the Si←N bond.

Design and discovery of materials guided by theory and computation is the current trend in materials science. The majority of modern building materials can be thought of as dispersions. Thus, particle systems should be considered as reasonable representations of both compositions and composites. Nowadays, there are numerous software packages available for modeling the particle dynamics. However, nearly all of such packages are targeted only to nano- and microscale spatial levels. For the R&D in building materials science, some specific functionality for macroscale modeling, along with simplified pairwise potentials, but complicated initial distributions and topology analysis methods have to be implemented. In the present article, we briefly represent the pathway from the problem of modeling the building materials as particle systems, through the general method of particle dynamics to the task of multiscale modeling, where we need unified modeling methods and single software implementation. Then, we introduce the Versatile Dynamics Simulator – dedicated software implementation of classical dynamics that was designed taking into account the demands of building materials science. Design goals and current state of the software are described.

Modification of Pechini method for synthesis of weakly agglomerated yttrium aluminum garnet powder has been presented. Modified synthesis procedure is based on an additional calcination process in KCl melt at 1000 °C and allows obtaining weaker agglomeration of nanoparticles. Structure, morphology and particle size have been defined using scanning electron microscopy technique, X-ray diffraction, and static light scattering. Adsorption ability of powders has also been studied. Diffraction patterns of samples confirm existence of only one YAG phase; the average size of particles is about 200 nm. The size of coherent-scattering regions was determined to be 40–50 nm. Steady-state luminescence properties and lifetimes of nanocrystalline YAG:Eu 3+ powders synthesized by standard and modified Pechini techniques were compared.

A method for the synthesis of 3-fluoroindoles from N-arylamines substituted with the CF2I group is described. The reaction is mediated by a ruthenium photocatalyst in the presence of a substoichiometric amount of triphenylphosphine upon irradiation with blue light. The starting N-arylamines are readily obtained by nucleophilic iododifluoromethylation of iminium ions.

1-Organyl-1-(trimethylsiloxy)-2-(dimethylamino)ethenes were synthesized for the first time, and their reactions with trichloro(methyl)silane and trifluoro(phenyl)silane afforded silicon bis-chelates, methylbis-[2-(dimethylamino)-1-(organyl)ethenolato-N,O]siliconium chlorides and bis[1-(dimethylamino)-3,3-dimethylbut-1-en-2-olato-N,O]fluoro(phenyl)silicon(IV), respectively.

The reaction of 1-(methylaminomethyl)silatrane with Ph 3 CCl in the presence of base leads to the formation of 1-[(N-methyl-N-tritylamino)methyl]silatrane 1 . Recrystallization of this silatrane from benzene/heptane (10:1) led to the formation of the solvate complex Ph 3 C(Me)NCH 2 Si(OCH 2 CH 2 ) 3 N·C 6 H 6 , the molecular structure of which was determined by single crystal X-ray analysis.

For the purpose of fire safe construction it is necessary to develop and investigate effects of fillers to flammability of building materials, including composite materials with polymer matrix. In present work we demonstrate the results of such investigation. We have examined influence of chemical composition, amount of mineral fillers to flammability, smoke-forming ability and limiting oxygen index of building materials based on different polymer binders. The experimental data indicate that the main parameter which determines the influence of mineral fillers on the flammability of composites is a specific heat absorbed by the filler. The dependence between limiting oxygen index and specific heat of mineral fillers is revealed for composites with epoxy matrices. This dependence is simple and beneficial for practical use.

Transfer hydrogenation of acetophenone and methyl benzoylformate with 2-propanol has been studied on rhodium nanoparticles obtained by the reduction of rhodium(I) complexes in the presence of optically active compounds, including chiral diamine S , S -DIODMA, (4 S ,5 S )- N 4 , N 4 , N 5 , N 5 ,2,2-hexamethyl-4,5-bis-(aminomethylene)-1,3-dioxolane, quaternary diammonium salt (4 S ,5 S )-(-)- N 1 , N 4 -dibenzyl-2,3-dihydroxy- N 1 , N 1 , N 4 , N 4 -tetramethylbutane-1,4-diammonium dichloride, and (8 S ,9 R )-(-)-cinchonidine. Increasing the modifier to Rh ratio leads to an increase in the enantiomeric excess ( ee ) of the reaction products. The greatest ee values (43.8% for ( R )-1-phenylethanol and 58.2% for the methyl ester of ( R )-mandelic acid) were achieved at (8 S ,9 R )-(-)-cinchonidine/Rh ratios of 9:1 and 3:1, respectively.

A novel strategy for the synthesis of 4-amino-3-cyano-2,2′- and 5′-amino-4′-cyano-2,3′-bipyrroles via readily available 1-amino-3-imino-3H-pyrrolizine-2-carbonitriles has been developed. The rearrangement leading to 5′-amino-4′-cyano-2,3′-bipyrroles involves formation of the intermediate aziridine, which undergoes other side ring-opening.

The results of experimental studies of the phase composition of oxide nanostructures formed by the local anodic oxidation of a titanium thin film are reported. The data of the phase analysis of titanium-oxide nanostructures are obtained by X-ray photoelectron spectroscopy in the ion profiling mode of measurements. It is established that the surface of titanium-oxide nanostructures 4.5 ± 0.2 nm in height possesses a binding energy of core levels characteristic of TiO2 (458.4 eV). By analyzing the titanium-oxide nanostructures in depth by X-ray photoelectron spectroscopy, the formation of phases with binding energies of core levels characteristic of Ti2O3 (456.6 eV) and TiO (454.8 eV) is established. The results can be used in developing the technological processes of the formation of a future electronic-component base for nanoelectronics on the basis of titanium-oxide nanostructures and probe nanotechnologies.

It is shown for the first time that the reaction of cyanopropargylic alcohols with carboxylic acids in the presence of triethylamine (5–100 mol%) under microwave irradiation (MeCN, 100 °C, 1.2 atm) follows two competing pathways to afford 4-cyano-3(2 H )-furanones (1:1 adduct) and 4-cyano-[( Z )-3-cyanomethylene]-2,3-dihydrofurans (2:1 adduct) in moderate to good yields. The ratio of the products depends on both the reaction conditions (the reactant ratio, catalyst content) and the reactant structure, the 2:1 adduct formation being favored by an excess of cyanopropargylic alcohol, lower catalyst content, and bulky substituents at the carboxylic functions. Both competing reactions proceed via the same intermediates, keto esters, which either intramolecularly cyclize to the 1:1 adducts, or intermolecularly add the second molecule of cyanopropargylic alcohol to give the 2:1 adducts.

The regio- and stereoselective reaction of 2-bromomethyl-1,3-thiaselenole with sodium N,N-dialkyl dithiocarbamates is accomplished at room temperature for two minutes in MeCN to afford (Z)-2-{[(dialkylamino)carbothioyl]sulfanylselanyl}ethenyl vinyl sulfides in up to 98% yield. At a longer time (8 h), the reaction regioselectively gives 2,3-dihydro-1,4-thiaselenin-2-yl N,N-dialkylcarbamodithioates in high yields. The latter are formed by rearrangement of the former compounds. DFT calculations show that the reactions proceed via a seleniranium intermediate. The formation of the products is the result of nucleophilic attacks of dithiocarbamate anion either at the selenium atom or at the carbon-2 atom of the seleniranium cation. The reaction leading to sulfanylselanylethenyl vinyl sulfides represents the first example of nucleophilic attack at the selenium atom of seleniranium intermediate.

Conditions for the synthesis of dispersion titanium dioxide with a developed roughness by molecular layering on the silicon surface were determined and structural characteristics of the resulting layer were studied. Electroactive surface area of the titanium dioxide nano-roughened films obtained by the proposed method is higher than those of the reference (smooth) titanium oxide film and the reference silicon electrode by factors 1.1 and 1.2, respectively.

The Pd(II)complexes [Pd(acac)(PR3)(PhCN)][BF4] and [Pd(acac)(S)2][BF4] (acac = acetylacetonate; R = phenyl, 2-methoxyphenyl; S = benzonitrile, pyridine, CD3CN) were synthesized by the reaction of Pd(acac)2 or Pd(acac)2·PR3 with 2 equiv. of BF3·OEt2 in the presence of appropriate ligands (S). The structural features of the complexes were analyzed by NMR and FTIR spectroscopies. Computed FTIR spectra was in agreement with the corresponding experimental data, the correlation between ν(CN) of the κ1-nitrile ligands and DFT-calculated geometrical features of the complexes was proposed. Complex Pd (κ2-O,O′-acac)(κ1-C-acac)(TOMPP) (TOMPP = tris(ortho-methoxyphenyl)phosphine) was characterized by X-ray diffractometry. XRD, 1H and 31P NMR analyses were consistent with formation of three unequally populated rotamers of Pd(κ2-O,O′-acac)(κ1-C-acac)(TOMPP) in CDCl3 which differ in the orientation of the endo-(2-methoxy)phenyl ring in exo2 conformation of coordinated TOMPP. Reaction of [Pd(acac)(PR3)(PhCN)]BF4 with L (L = pyridine, morpholine, TOMPP) in the majority of cases gave mixtures of [Pd(acac)(PR3)(L)]BF4, [Pd(acac)(L)2]BF4, and [Pd(acac)(PR3)2]BF4 as result of sequence of ligand substitution reactions. The cationic palladium catalyst precursors were found to be active catalysts for phenylacetylene polymerization and oligomerization. Only cationic pre-catalysts with bulky TOMPP ligand gave high-molecular weight polyphenylacetylene. Catalysts with less bulky substituents mostly formed phenylacetylene oligomers. When activated with BF3⋅OEt2, these palladium complexes can also be used as catalysts for the vinyl addition polymerization of norbornene with activities 104–107 gpolymer molPd h−1.

The Pd(II) complexes [Pd(acac)(L)n]BF4 were synthesized by the reaction of [Pd(acac)(MeCN)2]BF4 with L (n = 2: L = PCyPh2, PCy2Ph, P(NMe2)3, P(NEt2)3, tri-2-furylphosphine, tri-2-thienylphosphine; n = 1: L = 2 dicyclohexylphosphino-2′,6′-dimethoxybiphenyl, 2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl). The structural features of the complexes were analyzed by NMR and FTIR spectroscopies. Complexes [Pd(acac)(PCyPh2)2]BF4 and [Pd(acac)(PCy2Ph)2]BF4 were characterized by X-ray diffractometry. The cationic palladium catalyst precursors were found to be active catalysts for telomerization of 1,3- butadiene with methanol under base-free conditions. Complexes [(acac)Pd(PCy2Ph)2]BF4 and [(acac)Pd(TOMPP)2]BF4 in terms of yield, selectivity, and stability are effective for the catalytic telomerization (TOMPP = tris(2-methoxyphenyl)phosphine). Using 0.001–0.0025 mol% palladium loading methoxy-2,7-octadienes were obtained with chemoselectivities of 76–94% and TON up to 60000 mol 1,3-butadiene per mol Pd.

Memristor effect in ZnO thin films was investigated. It was shown, that increase in the number of laser pulses during the formation of a thin ZnO film from 1000 to 3000 leads to increase resistance of ZnO film in the high resistance state (HRS) from 28.31±8.27 kΩ to 1943.53±123.11 kΩ and decrease resistance of ZnO film in the low resistance state (LRS) from 3.85±2.15 kΩ to 3.22±1.32 kΩ, respectively. Memristor structure fabrication technique was developed. Al2O3/TiN/ZnO/Ti memristor structure was fabricated and investigated. Resistive switching from HRS to LRS occurred at 0.4±0.1 V, and from LRS to HRS at -0.72±0.2 V. Endurance test shown that HRS is 72.41±6.22 kΩ, LRS is 1.05±0.32 kΩ. It was shown, that HRS/LRS ratio was about 69.7 at read voltage 0.3 V. As a result, Al2O3/TiN/ZnO/Ti memristor structure fabrication allowed to decrease switching voltage from 3.2±0.6 V to 0.4±0.1 V for SET, and from -3.5±1.1 V to -0.72±0.2 V for RESET, decrease current from 0.9±0.4 mA to 5.2±2.2 μA, and get less resistance dispersion, than Al2O3/TiN/ZnO structure.

The re-quantization method&mdash, one of the resurgent analysis methods of current importance&mdash, is developed in this study. It is widely used in the analytical theory of linear differential equations. With the help of the re-quantization method, the problem of constructing the asymptotics of the inverse Laplace&ndash, Borel transform is solved for a particular type of functions with holomorphic coefficients that exponentially grow at zero. Two examples of constructing the uniform asymptotics at infinity for the second- and forth-order differential equations with the help of the re-quantization method and the result obtained in this study are considered.

Currently, thermoset-based polymer matrix composites are widely used for production of fire protective coatings. Intumescent properties of such coatings are highly dependent on composition. Expandable graphite is a prospective intumescent admixture; unfortunately, admixture of expandable graphite alone can lower the integrity of char residue down to unacceptable levels. The objective of the present work is to present the method that can be used for elimination of the mentioned drawback. The limiting values of expandable graphite in composite with two different admixtures - ammonium polyphosphate and ceramic cenospheres - were determined by means of study the structure of both intumescent epoxy composites and char residues of such composites. It was revealed that admixture of ceramic cenospheres leads to notable improvement of integrity of char residue. This improvement is mostly due to features of heat transfer in material with cenospheres which are characterized by low particle size and, at the same time, low heat conductance.

We analytically compute the four-loop QCD corrections for the colour structure $(d_F^{abcd})^2$ to the massless non-singlet quark form factor. The computation involves non-trivial non-planar integral families which have master integrals in the top sector. We compute the master integrals by introducing a second mass scale and solving differential equations with respect to the ratio of the two scales. We present details of our calculational procedure. Analytical results for the cusp and collinear anomalous dimensions, and the finite part of the form factor are presented. We also provide analytic results for all master integrals expanded up to weight eight., 16 pages, 2 figures

It is known that sulfur-extended asphalt is of improved operational properties. Binders with higher content of polymeric sulfur are characterized by higher operational properties. Unfortunately, many sulfur modifiers are volatile and toxic. The objective of article is to investigate the structure of sulfur with admixtures of saturated aliphatic hydrocarbon and two types of nanoscale carbon modifiers. It was shown that such admixtures lead to formation of the fine-crystalline structure of high uniformity; average size of crystals decreases in order of magnitude. Structural changes are accompanied by notable improvement of compressive strength (the values of compressive strength increases in about 3 times). The practical value of the conducted studies is due to possible application of nanomodified sulfur in road construction.

We review the four-loop QED corrections to the anomalous magnetic moment of the muon. The fermionic contributions with closed electron and tau contributions are discussed. Furthermore, we report on a new independent calculation of the universal four-loop contribution and compare with existing results., 6 pages, Contribution to the proceedings of the International workshop on e+e- collisions from Phi to Psi 2017, v2: references added

MPI-powered computations are extremely time-efficient. Thereby, parallel computation of reliability algorithms would allow us to provide rapid response to changes in technical conditions of artificial constructions.

The adhesion to a substrate of vertically aligned carbon nanotubes (VA CNT) produced by plasmaenhanced chemical vapor deposition has been experimentally studied by atomic-force microscopy in the current spectroscopy mode. The longitudinal deformation of VA CNT by applying an external electric field has been simulated. Based on the results, a technique of determining VA CNT adhesion to a substrate has been developed that is used to measure the adhesion strength of connecting VA CNT to a substrate. The adhesion to a substrate of VA CNT 70–120 nm in diameter varies from 0.55 to 1.19 mJ/m2, and the adhesion force from 92.5 to 226.1 nN. When applying a mechanical load, the adhesion strength of the connecting VA CNT to a substrate is 714.1 ± 138.4 MPa, and the corresponding detachment force increases from 1.93 to 10.33 μN with an increase in the VA CNT diameter. As an external electric field is applied, the adhesion strength is almost doubled and is 1.43 ± 0.29 GPa, and the corresponding detachment force is changed from 3.83 to 20.02 μN. The results can be used in the design of technological processes of formation of emission structures, VA CNT-based elements for vacuum microelectronics and micro- and nanosystem engineering, and also the methods of probe nanodiagnostics of VA CNT.

The crystal and molecular structures of 1-(iodmethyl)silatrane and 1-(iodpropyl)silatrane are determined by X-ray diffraction. The effect of the iodine heteroatom upon silatrane moieties of the molecules through oneand three-carbon chains is studied based on the geometric characteristics of the molecules and the analysis of their packings.

In the present article we have summarized the rutting resistance testing results of the sulfur extended asphalt. The results were obtained with help of three different methods – RU GOST 12801-98, AASHTO TP 63 and AASHTO T 324. It was confirmed that AASHTO test results adequately describe the ability of asphalt concrete to resist irreversible plastic deformation by repeated wheel load. It is found that rutting resistance of the sulfur extended asphalt can be in 1.3...3.7 times higher if compared with the rutting resistance of conventional asphalt concrete. To describe the kinetics of the rutting we have proposed the additive parametric model that represents two simultaneous processes – late densification and plastic flow. The parameters of the model are determined on the basis of the experimental data. It is shown that the rate of plastic flow monotonically decrease with the increase of the sulfur amount; this also demonstrates the high rutting resistance of the sulfur extended asphalt.

The necessary prerequisite of the fire safe construction that involves wide use of the polymer matrix composites (PMC) is the knowledge that allows to properly choose the values of mixture variables – e.g. ratio of phases, amounts of fire retardants and plasticizers – that affect the characteristics related to the fire safety – flammability, smoke-forming ability, limiting oxygen index, etc. In the present work we have studied the influence of the content of phosphorus- and chlorine-containing plasticizers to the heat resistance, flammability and smoke-forming ability of PMC based on different binders. For the limiting candle-like combustion, the thermochemical characteristics of phthalate and phosphate plasticizers are determined. It is found that for the materials based on epoxy oligomers and synthetic rubbers, no phosphate plasticizers can be practically used for the reduction of the fire hazard; such plasticizers only increase the flammability of PMC. It is also shown that the chemical nature of the phosphate plasticizer significantly affects the smoke-forming ability of PMC.

This article studies and compares the efficiency of linear and nonlinear vibration isolation systems. The estimation relies on the value of isolated mass standard deviation due to external oscillation with different spectral densities. The solution of nonlinear differential equation of isolated by nonlinear vibration isolator mass is based on harmonic linearization method. External excitation process is treated as white noise wideband process with different spectral densities. The main interest is attached to the definition of vibration criteria exceedance number for the isolated mass suspended on both types of vibration isolators. The article suggests the application of several practical formulas of exceedance number calculation.

An insoluble nanocomposite with copper nanoparticles (CuNP) stabilized by 1-vinyl-1,2,4-triazole and acrylonitrile copolymer was synthesized and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric data analysis. The nanocomposite showed high catalytic activity in the multicomponent synthesis of 1-benzyl-4-phenyl- and 1-benzyl-4-phenyl-5-(2-phenylethynyl)-1H-1,2,3-triazoles.

In this study, an integrated approach was used for the preparation of a nanotitanium-based bioactive material. The integrated approach included three methods: severe plastic deformation (SPD), chemical etching and atomic layer deposition (ALD). For the first time, it was experimentally shown that the nature of the etching medium (acidic or basic Piranha solutions) and the etching time have a significant qualitative impact on the nanotitanium surface structure both at the nano- and microscale. The etched samples were coated with crystalline biocompatible TiO2 films with a thickness of 20 nm by Atomic Layer Deposition (ALD). Comparative study of the adhesive and spreading properties of human osteoblasts MG-63 has demonstrated that presence of nano- and microscale structures and crystalline titanium oxide on the surface of nanotitanium improve bioactive properties of the material.

The results of an experimental study of the modification of probes for critical-dimension atomicforce microscopy (CD-AFM) by the deposition of carbon nanotubes (CNTs) to improve the accuracy with which the surface roughness of vertical walls is determined in submicrometer structures are presented. Methods of the deposition of an individual CNT onto the tip of an AFM probe via mechanical and electrostatic interaction between the probe and an array of vertically aligned carbon nanotubes (VACNTs) are studied. It is shown that, when the distance between the AFM tip and a VACNT array is 1 nm and the applied voltage is within the range 20–30 V, an individual carbon nanotube is deposited onto the tip. On the basis of the results obtained in the study, a probe with a carbon nanotube on its tip (CNT probe) with a radius of 7 nm and an aspect ratio of 1:15 is formed. Analysis of the CNT probe demonstrates that its use improves the resolution and accuracy of AFM measurements, compared with the commercial probe, and also makes it possible to determine the roughness of the vertical walls of high-aspect structures by CD-AFM. The results obtained can be used to develop technological processes for the fabrication and reconditioning of special AFM probes, including those for CD-AFM, and procedures for the interoperational express monitoring of technological process parameters in the manufacturing of elements for micro- and nanoelectronics and micro- and nanosystem engineering.

This essay is dedicated to the history of creation and development of the molecular layering technique (ML) which, in the modern community of non-Russian scientists, is commonly referred to as atomic layer deposition (ALD). Basic research in the field of chemical transformations of solid surfaces using the ML method in the light of the “framework” hypothesis proposed by V. B. Aleskovskii in 1952 is discussed. A number of questions raised by international scientists including those involved in the Virtual Project on the History of ALD (VPHA, 2013), and scientists from conferences in Helsinki (Finland, May 2014.), Kyoto (Japan, June 2014), and personal communications amongst peers are addressed. For the first time in English, this article provides information about V. B. Aleskovskii and S. I. Kol'tsov who are closely associated with development of the ML technique in the Soviet Union. This paper also informs the scientific community about research groups currently engaged in ML research in Russia and introduces the scientific school of “Chemistry of highly organized substances”, founded and supervised by V. B. Aleskovskii.

The CN-functionalized pyrrole(indole)-3(2H)-furanone derivatives are readily synthesized via the domino reaction of diverse pyrrole(indole) carboxylic acids with tertiary cyanopropargylic alcohols (Et3N, MeCN, MW reactor, 100 °C, 1.2 atm) in up to 93% yield.

The X-ray single-crystal structures of N-trimetylsilyl acetamide CH3CONHSiMe3 (1), N-trimethylsilyl trifluoroacetamide CF3CONHSiMe3 (2) and N-trimethylsilyl benzamide PhCONHSiMe3 (3) have been determined. Quantum chemical calculations (B3LYP/6-311+G**, NBO analysis) were performed for gas phase optimized structures, proton affinities and N–H bond dissociation energies of amides 1–3 and their isostructural carbon analogs 4–6. The effect of silicon atom on structural features and intermolecular electron interactions was determined. Types of self-associates which can be formed by amides 1–3 in CCl4 solution were studies by infrared spectroscopy.

The synthesis method of weakly agglomerated Y2O3 powders based on the decomposition of metal–polymer gel (Pechini method) has been developed. The physicochemical properties of powders synthesized by the standard Pechini method and a method using foaming components have been compared. The luminescence properties of Eu3+-doped Y2O3 have also been studied.

A method for the iododifluoromethylation of aromatic aldehydes using (bromodifluoromethyl)trimethylsilane (Me3SiCF2Br) is described. The selective formation of the CF2I group is based on using sodium iodide, with the sodium serving as a scavenger of bromide and iodide serving as a nucleophile with respect to difluorocarbene. The primary CF2I-addition products can undergo HI-elimination or iodine/zinc exchange followed by allylation in a one-pot manner.

3- and 4-Methylstyrenes react with red phosphorus in the superbase system KOH/DMSO (110 °C, 2 h) to afford tertiary phosphine oxides in 20–25% total yield. Under microwave irradiation (600 W) this ...

В статье анализируется политика российского государства в отношении молодежи с начала 18 до конца 20 века. Автор, предлагает собственную периодизацию государственной молодежной политики, указывая на циклический характер взаимоотношений государства и молодого поколения. Мы можем наблюдать рост интереса к новому поколению в периоды кризисов и модернизаций российского государства. В кризисные периоды на первое место выходит энергетический потенциала нового поколения, его способность к физическому и эмоциональному напряжению, его физиологический ресурс. Периоды государственной модернизации вызывают интерес к молодому поколению как группе, слабо интериоризировавшей социальные практики, доминирующие в обществе, и, соответственно, способной к успешной и быстрой трансформации.По мнению, автора в рассматриваемый период можно выделить пять циклов государственной молодежной политики. Каждый цикл тесно связан с началом государственной модернизации социально-экономической и политической системы общества. Именно в этот исторический момент, государственная власть остро нуждается в молодом поколении, как группе слабо интегрированной в социальную структуру общества. В каждом из пяти циклов выделяются три повторяющиеся фазы.На протяжении последних нескольких веков можно выделить устойчивые и повторяющиеся формы и методы молодёжной политики. Существование подобных паттернов позволяет рассматривать молодёжную политику российского государства в историческом контексте как процесс воспроизводства в разных социокультурных условиях схожих практик работы с молодым поколением. Изучение особенностей взаимоотношений государства, общества и молодого поколения на разных исторических этапах, выделение в этом процессе устойчивых паттернов становится важным инструментом прогнозирования особенностей и перспектив развития современной российской молодёжной политики.

Techniques are developed to determine the resistance per unit length and the electrical resistivity of vertically aligned carbon nanotubes (VA CNTs) using atomic force microscopy (AFM) and scanning tunneling microscopy (STM). These techniques are used to study the resistance of VA CNTs. The resistance of an individual VA CNT calculated with the AFM-based technique is shown to be higher than the resistance of VA CNTs determined by the STM-based technique by a factor of 200, which is related to the influence of the resistance of the contact of an AFM probe to VA CNTs. The resistance per unit length and the electrical resistivity of an individual VA CNT 118 ± 39 nm in diameter and 2.23 ± 0.37 μm in height that are determined by the STM-based technique are 19.28 ± 3.08 kΩ/μm and 8.32 ± 3.18 × 10−4 Ω m, respectively. The STM-based technique developed to determine the resistance per unit length and the electrical resistivity of VA CNTs can be used to diagnose the electrical parameters of VA CNTs and to create VA CNT-based nanoelectronic elements.

We propose a complex model of local anode oxidation of metals taking into account the processes occurring in the probe-substrate system in dry air, in water vapor, and in the water film adsorbed on the substrate surface. It is shown that local anode oxidation occurs due to generation of oxygen ions as a result of decomposition of water molecules in an electric field; the predominant source of oxidizer is the film of water adsorbed on the substrate surface. The results of numerical simulation of local anode oxidation of titanium demonstrate good correlation with experimental dependences of the height of oxide nanostructures on the duration of local anode oxidation, which confirms the effectiveness of the proposed model. Our results can be used in the development of technological processes of formation of elements of nanoelectronics by local anode oxidation.

Secondary phosphine chalcogenides react with diacetone-d-glucose (DAG) in the system CCl4/Et3N (70°C, 4–24 h) to afford DAG chalcogenophosphinates in up to 79% yield, thus paving a short way to optically active chalcogenophosphinates with glucose moieties. As an example, a mild regioselective hydrolysis (70°C, aqueous MeCOOH) of DAG bis(2-phenylethyl)selenophosphinate) obtained leads to monoacetone-d-glucose bis(2-phenylethyl)selenophosphinate.

A series of copper(I) scorpionates, [Cu(N,N′,N″-2-Py3P X)Hal] (X = O, S and Se; Hal = Cl, I), has been synthesized in 67–88% yields by the reaction of tris(2-pyridyl)phosphine chalcogenides with Cu(I) halides (CH2Cl2, r.t., 10 min). These complexes were characterized by X-ray crystallography, NMR and UV–Vis techniques to reveal that the ligand coordinates with Cu(I) ion via three pyridine nitrogen atoms to form near-C3-symmetrical [Cu(N–C)3P X] cage. The halogen atoms are bonded with metal so that the latter adopts a distorted trigonal pyramidal geometry. The DFT computations confirm that the observable κ3-N,N′,N″-binding of the ligands is energetically more favorable than the alternative coordination modes, i.e. κ1-X-monodentate, κ2-N,N′- or κ2-N,X-bidentate and κ3-N,N′,X-tridentate.

Alumina micro- and nanopowders with the particle size from 200 μm to 40 nm synthesized by the sol-gel method are studied. The particle size dependence of γ-Al2O3→α-Al2O3 phase transformation is studied by differential thermal analysis, X-ray diffraction method, and transmission electron microscopy. X-ray diffraction data show that for alumina nanoparticles γ-Al2O3→θ-Al2O3 phase transformation occurs at 900°C, and for micro-particles it occurs in the temperature range 1150–1200°C. The alumina ceramics produced of alumina nanoparticles is shown to have higher flexural strength under three-point bending than the ceramics produced of micro-particles. The obtained results demonstrate that alumina particle size reduction stabilizes the formation of α-Al2O3 at lower temperatures, due to which the grain growth rate decreases and the flexural strength of monolithic oxide ceramics increases.