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The structure of individual multi-wall carbon nanotubes exposed to irradiation by a argon ions and electron flux, as well as subsequent heat processing in an inert medium has been studied using transmission electron microscopy and x-ray photoelectron spectroscopy. It has been shown that irradiation with argon ions and electrons leads to the formation of defects in the structure of carbon nanotubes, changes in the interlayer distance in the walls of nanotubes, and the fixing of functional oxygen-containing groups on their surface. Annealing of pre-irradiated nanotubes in an inert atmosphere causes a partial restoration of the multi-wall carbon nanotube structure. At the same time, in the case of irradiation with argon ions, the nanotube structure is being recovered and the oxygen concentration decreases. In the case of electron irradiation after annealing, extended multi-vacancy defects occur, on which functional groups containing a double chemical bond of carbon and oxygen (C=O) are formed. Using calculations carried out within the framework of density functional theory, the coupling energy values and optimized geometry for various configurations of vacancy clusters in the graphene plane have been obtained.

В России основными источниками редкоземельных элементов (РЗЭ) являются апатит и лопарит. Лопарит – комплексный титанат и ниобат, содержащий до 30 % мас. оксидов РЗЭ преимущественно цериевой группы. Доочистку, групповое разделение, выделение индивидуальных концентратов РЗЭ проводят с применением экстракционных методов, широко используемый для этих целей экстрагент – трибутилфосфат (ТБФ). Экстракционные технологии имеют ряд недостатков, в частности, большое число ступеней разделения из-за невысоких коэффициентов разделения индивидуальных РЗЭ в совокупности с трудностями разделения жидких фаз. Исключить последний недостаток можно при использовании сорбентов, содержащих ТБФ. В качестве носителей можно использовать как органические полимеры, так и неорганические соединения; среди последних широко используется кремнезём, который и был выбран в рамках данного исследования. В статье кратко описана методика синтеза образцов сорбентов. В качестве исходных реагентов для синтеза были использованы тетраэтоксисилан, трибутилфосфат, хлорид олова и нанотрубки. Для синтезированных образцов определен ряд физико-химических свойств (объем пор и их средний диаметр, площадь и морфология поверхности, кислотно-основные свойства поверхности), проведен термогравиметрический анализ. Сорбционные свойства образцов были проверены на примере извлечения РЗЭ из технологических растворов лопарита. В результате получены коэффициенты разделения пар Sm/La до 3,7, Pr/Nd – до 1,8, поэтому потенциально изученные образцы могут быть использованы для выделения самария из суммы РЗЭ, а также для разделения пары Pr-Nd.

We have developed a model for calculating the Raman spectra for optical phonons localized in diamond nanocrystals. The novelty of this approach is that it includes the contribution of localized phonons with dispersion over the entire Brillouin zone (3D model). The model is refined in that the phonon dispersion is calculated in the well-tested bond-charge model. The effects of the contribution to the Raman spectra from longitudinal optical phonons with frequencies higher than their frequency at the center of the Brillouin zone are considered. Comparative analysis of the calculated spectra and experimental spectra obtained from nanopowders and nanocrystalline diamond film is performed.

The article considers and analyzes an important stage in the development of laser systems for metal vapor from the point of view of biomedical applications. Since the advent of the first generation of domestic medical facilities with pulsed lasers on metal vapors, in particular, copper vapors (LSM), which were created in the FSUE “Research and Production Enterprise ‘Istok’”, not much time has passed. Now similar studies are widely developed and include a variety of uses, for instance, in oncology for treatment with photodynamic therapy (PDT), angioplasty of intravascular destruction of atherosclerotic lesions, dermatology and cosmetology for the treatment of facial skin defects, as well as otorhinolaryngology, gynecology, proctology, urology, and others. In that cases, doctors use the Yantar-2Fand Yakhroma-2 installations, developed on the basis of the “Kurs” LPM with radiation wavelengths λ = 510.6 nm and 578 nm and the average radiation power Prad= 5–10 W and tunable in wavelengths in the range of λ = 620–670 nm. Laser radiation is delivered to the affected area of a bio-object using a flexible light-guide cable with a diameter of 400, 600 or 800 μm fiber, which is one of the most convenient medical instruments. A compact and air-cooled medical installation of the new generation “Yakhroma-Med” based on the pulsed LPM “Kulon” with an average radiation power at the output of the light-guide cable Prad= 1–3 W uses in dermatology and cosmetology (together with the Lebedev Physics Institute of the Russian Academy of Sciences). Today, YakhromaMed is the leader in non-ablative technologies and is optimal for removing vascular, pigmented and unstained skin defects, treating acne and smoothing wrinkles. It is used in more than 100 clinics in Russia and abroad. Moreover, for scientific and practical medicine in the field of oncology, low-intensity laser therapy and surgery, dermatology and cosmetology, etc., a compact air-cooled industrial multifunctional high-intensity medical unit “Kulon-Med” (similar to Yakhroma-Med) based on two pulsed lasers was developed: LM “Kulon” with an average radiation power Prad= 10 W and LVRK with radiation tunable in wavelengths in the range λ = 620–750 nm and radiation power Prad= 1–3 W (together with Ltd. NPP VELIT, Kurchatov Institute and the Hertzen Hermitage Research and Development Institute). The laser radiation is transported using four flexible light-guide cables with a conductive quartz fiber diameter of 400 and 600 μm, which makes it possible to perform a therapeutic and prophylactic procedure simultaneously in several rooms. Medical facilities of this class have been put in many medical institutions. This report on the use of CVL in medicine says only about the developments in theMoscow region.

The structure and properties of the individual multi-walled carbon nanotubes (MWCNT) subjected to He:O plasma treatment (250 W) have been studied by means of SEM and IR-spectroscopy. It is shown that plasma treatment causes formation of extended defects and oxidation of graphene layers in the MWCNT`s walls. In this case, rounded craters up to 50 nm in size are formed on the surface of the nanotubes. The increment of treatment time leads to formation of graphene belts. The results of numerical modeling indicate the possibility of multivacancy defects formation in the structure of graphene planes by means of carbon atoms substitution.

The need for using isotopes in the nuclear power engineering, medicine, as well as in the sphere of control of engineering and construction facilities is increasing annually. However, the isotope separation methods do not allow to meet the need for production of a significant list of isotopes, including the purity of lithium isotopes. The process of amalgamation to date is the main technology of enrichment of 7Li in practical use. Other methods have very low separation efficiency and are not suitable for mass production. The present work is devoted to a new method for enriching the isotope 7Li, in parallel, the work presents the method of separating lithium isotopes by amalgamation modified by authors. The study relates to physical chemistry, in particular to electromigration processes and methods for separating lithium isotopes. A new promising approach for separating Li isotopes is the electrodialysis process using an ionic liquid as an electrolyte. Data on the relevance and uses of 7Li isotopes are given, the existing methods and criteria for the separation of lithium isotopes are considered. The article briefly describes the principle of the new technology, the regimes of enrichment experiments and the details of analysis of products obtained. Moreover, the new technology demonstrates the good environmental characteristics, it is amenable to mass production and has very low power consumption. However, it should be also emphasized that ionic liquids are very sensitive to impurities which inevitably appear in the electrolyte during separation process. One of the most important characteristics of isotope separation methods and technologies is the specific energy consumption, so currently the problem of reducing energy consumption is acute, for which it is necessary to create new methods for separation and purification of isotope systems and modernization of technologies already introduced in industry. The proposed method for enriching the 7Li isotope is carried out by controlling the process of electromigration of lithium ions through ion-exchange membranes in the electrolytic cell compartments. The work in the long-term future can ensure an increase in the efficiency of enrichment process for the 7Li isotope and a decrease in specific energy costs.

In recent years, the appearance of high-power fiber lasers, more efficient and easier to operate than other types of lasers, made it necessary to conduct systematic studies and develop a technology for cutting glass by the method of controlled thermal splitting. The paper considers the question of the possibility of high-speed cutting of glass by modern lasers with a power of up to several tens of kilowatts in the near-IR radiation range. In order to achieve the goal set in the work, the problem of determining the field of elastic stresses arising in a glass plate when it is heated by laser radiation has been solved. The method of investigation is based on the theory of thermoelasticity. We have proposed a mathematical model for calculating the three-dimensional temperature distribution and elastic stresses caused by the irradiation of the glass by a moving laser beam and have presented the results of numerical simulation of temperature fields and elastic stress profiles at different irradiation spot velocities. At high radiation powers, the maximum achievable cutting speed of glass is shown to be directly proportional to the power. The data on the speed of Bohr glass at low radiation powers (less than 400 W) available in the literature we have extrapolated to a high power (up to several tens of kilowatts). The investigation shows that the cutting speed can reach 70 cm / s at a laser radiation power of 20 kW. For cutting large-sized glass sheets in mass production, the fiber ytterbium lasers having a wavelength of 1.065 m are recommended. These lasers meet the requirements for power level, irradiation stability and service life. In addition, they have the ability to transport radiation through a fiber optic cable and the ability to automatically control the spatial location of the radiation spot. The results obtained can be used to develop new technologies for cutting glass on industrial lines for the production of float glass, in the process of cutting glass sheets and cutting 3D articles. The method of laser controlled thermal splitting, in comparison with other methods of laser cutting glass, is more efficient and stable, and also has a much wider range of applications, because allows increasing in several times the thickness of the divided glass.

The widespread introduction of polymer composite materials in key sectors of modern industry such as wind and hydropower engineering, aircraft and machinery ones, etc. due to the high level of their strength properties, versatility and ability to provide the lowest weight of parts of products raises the problem of their processing. Traditional processing methods (mechanical and abrasive water jet machining) have some significant shortcomings: high tool wear, delamination due to vibration and shock loadings, limitations on the cutting contour and others. The paper deals with the polymer composites laser machining which is considered to be one of the promising solutions for elimination of conventional methods disadvantages due to a contact-free, flexible and high-performance processing method. As a result of analysis of theoretical and experimental domestic and foreign works, the use of industrial ytterbium fiber lasers are found to be a promising direction for high-quality and productive processing of polymer composite materials. The results of studies using the experimental technological setups on the basis of nanosecond pulsed and continuous ytterbium fiber lasers with a radiation power up to 1 kW and optical scanning systems based on the biaxial galvo scanners and focusing F-Theta lenses with beam travel speeds up to 20 m / s have shown that the laser multi-pass machining of polymer composite materials with layer-by-layer removal (ablation) of the material due to the evaporation mechanism allows for precise and high quality cutting and drilling of carbon and glass fiber reinforced plastics and carbon plastics with a thickness 1–3 mm.

The Raman spectra of GaAs/AlAs(100) superlattices are calculated and studied experimentally for various wave-vector directions. The experiments are performed when applying a confocal optical microscope combined with a micro-Raman spectrometer for various scattering geometries both for phonons with a wave vector directed along the normal to a superlattice and in the in-plane geometry. The frequencies and eigenvectors of phonons are calculated in the extended Born model approximation taking into account Coulomb interaction in the rigid-ion approximation. The Raman spectra are calculated in the scope of the deformation- potential mechanism; herewith, it turns out that additional peaks, which are not described in the scope of this approach, appear in the experimental spectra. It seems likely that these peaks appear due to the manifestation of Raman scattering forbidden by selection rules under resonance conditions. An attempt is made to explain the appearance of these peaks in the experimental spectra within the scope of inelastic phonon scattering at bound charges (phonons with a large dipole moment).

This paper reports the development of a new-generation short-period borehole electrodynamic seismometer designed for research, with special emphasis on seismology and volcanology (Sobisevich et al., 2008) and for important applications (Bashilov, 2001), e.g., developing special monitoring and security systems, as well as the search for and monitoring of hydrocarbon exploration.

The synthesis and research of copper subgroup metal complexes with organic ligands, which have several heteroatoms in their structure, is highly perceptive. Since the resulting complex compounds differ in physical and chemical properties from the original organic compounds they will have a set of new characteristics of practical significance. In this study, 2-mercaptonicotinic acid and 2-mercapto-4(3H)-quinazolinone were used. During the research, complex compounds of metals of the copper subgroup were obtained from aqueous and water-alcohol solutions. The resulting compounds represent colored powder-like materials. The coordination of the organic reagent to metal ions was established by instrumental methods of analysis. The effect of the introduced reagent (alkali, ammonia) on the coordination of the organic reagent was investigated.

The splitting of long-wave optical phonons that arises in biaxially stressed zinc-blende- and diamond-type crystals due to violation of cubic symmetry in such crystals was studied both theoretically and experimentally (using micro-Raman technique). The anglular dispersion of optical phonons near the center of the Brillouin zone was calculated for split modes in biaxially stressed (001)-oriented films. The results obtained were used to analyze the effects due to strain and alloying on optical-phonon frequencies in stressed Ge, InGaAs and InAlAs films grown on GaAs (001) substrates. The developed approach permits a more precise determination of both the composition and the biaxial strain in AIIIBV alloy films based on an analysis of Raman spectra taken from such films.

An experimental setup for precision processing of composite materials based on nanosecond pulsed and continuous ytterbium fiber lasers with a wavelength of 1.06 μm and a radiation power up to 1 kW with an optical scanning systems based on galvanic drives with a beam velocity of up to 17 m/s has been developed. The setup provides a power density in a focused light spot with a diameter of s100 μm using a continuous laser of 107 W/cm2 and a pulsed laser of 109 W/cm2, which is one order of magnitude higher than the threshold values necessary for removing carbon fiber in the evaporation mode. The focus depth of the focused radiation allows for high-quality processing of sheet blanks.

A set of nanocrystalline diamond films was grown using microwave plasma enhanced chemical vapor deposition on fused silica substrates from methane diluted by hydrogen: with and without the addition of trimethylborane. The boron to carbon ratio in the gas phase was varied from 0 to 8000 ppm. The boron doped nanocrystalline diamond films were investigated using atomic-force microscopy, Raman spectroscopy, transmittance spectroscopy and electro-physical methods. For analysis of Raman spectra of heavily doped p-type nanocrystalline diamond using Fano contour one should take into account the shift and broadening of the phonon line due to phonon confinement in grains, or phonon scattering by defects. Raman spectra were calculated using a phonon confinement model and Fano contour. Good agreement was found between the calculated and experimental spectra. Analysis of the spectra showed both the phonon confinement effect in nanocrystalline grains and Fano interference effect due to the contribution of electron Raman scattering in heavily doped p-type diamond films. An increase in boron concentration led to a decrease in the size of crystalline diamond grains and also formation of defects (supposedly inclusion of sp2 hybridized carbon) in the nanocrystalline diamond films. Raman spectroscopy data was supplemented by data from atomic-force microscopy. The conductivity of undoped films was 0.066 Ω-1cm-1, the conductivity of doped films grew with increasing boron to carbon ratio and reached 418 Ω-1cm-1 (8000 ppm). Films were semitransparent and have good conductivity, so can be used as transparent electrodes in large-scale electronics and optoelectronics.

Using the methods of scanning electron microscopy (Scanning Electron Microscope – SEM) and X-ray photoelectron spectroscopy (XPS), changes in the atomic structure and chemical state of multi-walled carbon nanotubes (MWCNTs) due to the action of ion beams of argon and helium with different irradiation parameters were investigated. Based on the experimental XPS and XANES (X-ray absorption near edge structure) data, as well as theoretical data, changes in the density of electronic states near the Fermi level in MWCNTs after ion-beam action were analyzed. It is shown that the use of beams of argon and helium ions can be used for directional functionalization of MWCNTs and applications in the chemical and petrochemical industries.

The angular dependence of Raman scattering selection rules for optical phonons in short-period (001) GaAs/AlAs superlattices is calculated and experimentally studied. Experiments are performed using a micro-Raman setup, in the scattering geometry with the wavevectors of the incident and scattered light lying in the plane of superlattices (so-called in-plane geometry). Phonon frequencies are calculated using the Born model taking the Coulomb interaction into account in the rigid-ion approximation. Raman scattering spectra are calculated in the framework of the deformation potential and electro-optical mechanisms. Calculations show an angular dependence of the selection rules for optical phonons with different directions of the wavevectors. Drastic differences in the selection rules are found for experimental and calculated spectra. Presumably, these differences are due to the Frohlich mechanism in Raman scattering for short-period superlattices.

In the web infrastructure of information search, the use of semantic methods is considered to be a new round of the technology development. With the emergence of big data, a relevant issue is processing large amounts of data to extract valuable knowledge, especially for text files in natural language. Practice shows that traditional natural language search engines cannot always extract the necessary data from such data sets, as they do not take into account several subtle aspects of the language used in human speech. To solve this problem, the possibilities of using semantic search engines for text processing are being explored. This paper discusses the possible use of the semantic field model developed by the authors, to create a semantic search engine. Experiments have shown that using this model can improve the search accuracy. This model can be additionally used in creation of interactive dialogue systems.

The review is devoted to the current state of researches in the field of nanostructures and materials science - nanocomposite materials based on multiwalled carbon nanotubes (MWCNT). Methods of formation, methods of functionalization, physical properties of the nanocomposites based on layers, ensembles and individual MWNTs and nanostructured metal oxides (SnOx and TiOx) have been considered in detail. Prospective applications of the new nanocomposite materials as sensitive media in new generation gas sensors and chemical current sources have been considered.

Hydrodynamic and physicochemical studies of petrosoluble samples of antiturbulent additives of colloidal form are performed. The component composition of the dispersion medium and the active component content in each sample are determined. It is shown that the highest antiturbulent efficiency among studied agents of decreasing the hydrodynamic resistance is inherent to a petrosoluble additive with the numerical value of the “concentration semieffect” C DRmax/2 = 0.0013 kg/m3. Recommendations for optimum applications of antiturbulent additives in energy saving in oil and oil product transport technologies are developed.

The angular anisotropy of interface phonons and their interaction with optical phonons in (001) GaAs/AlAs superlattices are calculated and experimentally studied. Experiments were performed by Raman light scattering in different scattering geometries for phonons with the wave vector directed normally to the superlattice and along its layers. Phonon frequencies were calculated by the extended Born method taking the Coulomb interaction into account in the rigid-ion approximation. Raman scattering spectra were calculated in the Volkenshtein bond-polarizability approximation. Calculations confirmed that the angular anisotropy of phonons observed in experiments appears due to interaction (mixing) of optical phonons, in which atoms are mainly displaced normally to superlattices, with interface phonons (TO-IF modes). In the scattering geometry, when the wave vector lies in the plane of superlattice layers, the mixed TO-IF modes are observed under nonresonance conditions. The Raman spectra for TO-IF modes depend on the mixing of atoms at heteroboundaries.

Équipe 104 : Nanomatériaux; International audience; The improved phonon confinement model developed previously [11] is applied for definition of germanium nanocrystal sizes from the analysis of its Raman scattering spectra. The calculations based on the model allow determining the sizes of germanium nanocrystals more precisely from the analysis of their Raman spectra. In some cases, the comparative analysis of Raman data and electron microscopy data is carried out, and good agreement is observed.

We develop a model for calculating the Raman scattering spectra from phonons confined in for silicon nanocrystals, which is based on the familiar approach taking into account the uncertainty in the quasi-momentum of phonons localized in the nanocrystals. The model is considerably improved by taking into account dispersion of phonons not only in the magnitude of the quasi-momentum, but also in its direction. A significant refinement of the model is also due to the fact that phonon dispersion is calculated using the widely approved Keating model instead of being approximated by empirical expressions as was done in earlier approaches. The calculations based on this model make it possible to determine the sizes of silicon nanocrystals more precisely from analysis of the experimental Raman spectra.

The possibility of using laser systems to form beams with special spatial configurations has been studied. The laser systems applied had a self-conjugate cavity based on the elements of copper vapor lasers (LT-5Cu, LT-10Cu, LT-30Cu) with an average power of 5, 10, or 30 W. The active elements were pumped by current pulses of duration 80–100 ns. The duration of laser generation pulses was up to 25 ns. The generator unit included an unstable cavity, where one reflector was a special mirror with a reflecting coating. Various original optical schemes used were capable of exploring spatial configurations and energy characteristics of output laser beams in their interaction with micro- and nanoparticles fabricated from various materials. In these experiments, the beam dimensions of the obtained zones varied from 0.3 to 5 µm, which is comparable with the minimum permissible dimensions determined by the optical elements applied. This method is useful in transforming a large amount of information at the laser pulse repetition rate of 10–30 kHz. It was possible to realize the high-precision micromachining and microfabrication of microscale details by direct writing, cutting and drilling (with the cutting width and through-hole diameters ranging from 3 to 100 µm) and produce microscale, deep, intricate and narrow grooves on substrate surfaces of metals and nonmetal materials. This system is used for producing high-quality microscale details without moving the object under treatment. It can also be used for microcutting and microdrilling in a variety of metals such as molybdenum, copper and stainless steel, with a thickness of up to 300 µm, and in nonmetals such as silicon, sapphire and diamond with a thickness ranging from 10 µm to 1 mm with different thermal parameters and specially designed laser beam.

The article deals with a fundamentally new fluoride technology for obtaining fluoride materials, provides data on the kinetics of the process of fluorination of Fe oxide with fluorine, fluoride and ammonium bifluoride. The physical and chemical properties of obtained fluorides are shown: a study of the elemental composition, grain-size composition using the method of scanning electron microscopy and laser diffraction.

The conditions of the acousto-optic interaction in the crystals with gyrotropy are considered. The optimal length of the acousto-optic interaction and the diffraction efficiency in the gyrotropic direction are calculated. The diffraction efficiency is determined by the coupled wave method which allows calculation of the field interaction in the gyrotropic crystal [1]. It is theoretically shown and experimentally confirmed that the diffraction efficiency in the gyrotropic direction is independent of incident light polarization, when the polarization plane rotates by 45° along the interaction length.

The possibilities of the isotope-selective excitation of molecules by CO laser radiation. More specifically, the problem of determining the conditions of the preferable excitation of heavy isotope 3C18O compared to the light isotope 12C18O is set. A carbon monoxide molecule is capable of absorbing at hundreds of vibrational-rotational lines within the principal absorption band of the CO molecule over the 1200–2600 cm−1 range. Since radiation absorption is negligibly low in the frequency range below 1900 cm-1 and there are no appreciably efficient radiation sources over the 2200–2600 cm−1 range in which absorption can be observed, the 1900–2200 cm−1 frequency range is considered in this work. The presented calculations may refer to the selective excitation of the gas phase in bulk and in gas absorbed on the surface.

A relation for calculating the volume fluid rate through a cylindrical channel under turbulent conditions, which is a function of the dynamic velocity, tube radius, and kinematic viscosity of liquid, is proposed. Experimental testing of the derived formula, performed on liquids of different chemical nature (water and petroleum) showed the reliability of calculated results in theoretical prediction of the volume flow rate under turbulent fluid flow conditions.

The short-range order during gas adsorption by micropores can be described based on integral equations of statistical mechanics for partial distribution functions. The assumptions necessary for correct analysis of physical sorption are considered, and adsorption characteristics of carbon nanofibers in relation to hydrogen are calculated.

Spectral-energy and inertial properties of very long-persistent (> 10 h) phosphor SrAl2O4:Eu2+, Dy3+ were studied using semiconductor light-emitting diodes and other optical radiation sources in the blue and near-ultraviolet regions. The light store accumulated in this phosphor (up to 1 · 1016 photon/cm2) was estimated and its luminescence kinetics was discussed. The prospects of its application, including phosphor grain introduction into films, were considered.

Research on CVL installations with an average power of 20–25 W of cutting and drilling has shown wide range of applications of these lasers for micromachining of metals and a wide range of non-metallic materials up to 1–2 mm. From the analysis indicated that peak power density in the focused light spot of 10–30 μm diameter must be 10 9 –10 12 W/cm 2 the productivity and quality micromachining, when the treatment material is preferably in the evaporative mode micro explosions, followed by the expansion of the superheated vapor and the liquid. To achieve such levels of power density, a minimum heat affected zone (5– 10 μm) and a minimum surface roughness of the cut (1–2 μm), the quality of the output beam of radiation should be as high. Ideally, to ensure the quality of the radiation, the structure of CVL output beam must be single-beam, diffraction divergence and have at duration pulses τi = 20–40 ns. The pulse energy should have low values of 0.1–1 mJ at pulse repetition rates of 10–20 kHz. Axis of the radiation beam instability of the pattern to be three orders of magnitude smaller than the diffraction limit of the divergence. The spot of the focused radiation beam must have a circular shape with clear boundary, and a Gaussian intensity distribution.

The technique of Raman spectroscopy has been used to investigate doped (n-type) and undoped GaAs/AlAs superlattices with AlAs barrier thicknesses from 17 to 1 monolayers. The peak corresponding to the scattering by a two-dimensional plasmon was found in the Raman spectrum of a doped superlattice with relatively thick barriers. The position of the experimental peak corresponded to the value calculated in the model of plasma oscillations in periodic planes of a two-dimensional electron gas. The electron tunneling effects played an increasingly prominent role as the AlAs barrier thickness decreased. The peaks corresponding to the scattering by coupled phonons with three-dimensional plasmons were found in the Raman spectra for a superlattice with an AlAs thickness of 2 monolayers; i.e., the delocalization of coupled modes was observed. In this case, the folding of acoustic phonons was observed in the superlattice under consideration, indicative of its good periodicity, while the localization of optical phonons in GaAs layers was observed in undoped superlattices with an AlAs thickness of 2 monolayers.

The influence exerted by the composition of film-forming solutions based on acetylacetone on the electrical and optical properties of indium-tin oxide films obtained from these solutions by the dip-coating process was revealed.