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The distributions of the 13C NMR-measured structural-group composition parameters of the Lena–Tunguska basin crude oils were obtained. All these distributions were shown to be far from normal, many of them being asymmetric and/or bimodal. These oils exhibit a significantly lower content of aromatics than the Volga–Urals and Western Siberia oils. The principal maximum of Car distribution lies in the distribution tail areas of the other two basins. The Lena–Tunguska oils are free of fluids with low content (below 14 abs %) of n-alkyl structures. It was also demonstrated that the crude oils sampled from the basin’s two major tectonic structures, namely the Baikit anteclise and the Nep-Botuob anteclise, differ significantly from one another in the concentrations of aromatics and n-alkyl structures.

Transients in a high- and medium-voltage power-supply network due to switching operations and short circuits are accompanied by high-frequency overvoltage pulses. Their amplitude and frequency characteristics are needed to select proper protection devices. Only experimental study can give us reliable data on such characteristics. The paper presents overvoltage spikes experimental study data in switchgears of 6–500 kV. The spikes were measured by means of recorder with noncontact capacitive sensors. Experimental studies at power-engineering facilities showed that most hazardous phenomena are high-frequency resonances. In this case, the overvoltage values are over ten times higher than nominal voltage amplitude. The usual method of connecting protection device to mains via a conductor a few meters long was shown to be inadequate to provide equipment protection. RC circuits are needed for this situation.

The effect of laser radiation with a wavelength near 1.55 µm on the photoluminescence properties of “nitrogen-vacancy” (NV) color centers in diamond has been studied experimentally. The effect of radiation of an infrared laser on the charge state of color centers redistributes the spectral intensity of photoluminescence in the ensemble of NV centers. In the case of neutral NV centers, the quenching of photoluminescence reaching about 60% has been observed. A feature of the laser excitation of NV centers by this method is the absence of competition with stimulated emission and two-photon excitation, which is observed with an increase in the power of infrared radiation at other wavelengths.

This article presents the results of the creation of laboratory equipment for the production of nano- and microfibres by the method of multi-layer electrospinning, a detailed description of the parts of the resulting device is given, such as a device for feeding a polymer solution into the electrospinning zone and a collector assembly. The main parameters of the device, the principle of operation and modes of electrospinning are described. Comparison with similar devices, advantages and disadvantages of different options for supplying solutions to the electroforming zone are presented. The results of experimental studies on this installation are presented on the example of aqueous solutions of sodium alginate and polyvinyl alcohol, and their mixtures. The regimes of stable electrospinning are experimentally determined. Samples of nanomaterials were obtained from mixtures of these polymer solutions. A morphological analysis of the obtained materials and a histogram of the fibre diameter distribution were carried out.

The photoluminescence intensity in lithium niobate crystals close to the stoichiometric composition being lower than in a congruent crystal was established. The increase of Li / Nb ratio leads to shifting the photoluminescence bands to the short-wavelength region of the spectrum and changing the fundamental absorption edge of the crystals under study. It was shown that, in addition to point defects in the cationic sublattice, complex defects due to the presence of OH groups and compensation defects (VLi / VNb) in the structure can also contribute to photoluminescence.

The article analyzes A. Solzhenitsyn's little known play The Light Which Is in Thee [Svet, kotoriy v tebe] (The Candle in the Wind [Svecha na vetru]), conceived and written in 1960. The play is a concentration of the most important ideas further developed in the writer's subsequent output. Other works are considered with regard to the play: The Gulag Archipelago [Arkhipelag Gulag], The Oak and the Calf [Bodalsya telyonok s dubom], Matryona's House [Matryonin dvor], Nastenka, One Day in the Life of Ivan Denisovich [Odin den Ivana Denisovicha], and A Letter to the Soviet Leaders [Pismo vozhdyam Sovetskogo Soyuza]. The article attempts to identify typical traits of Solzhenitsyn's thinking and style as revealed in the works created after The Light Which Is in Thee. The author finds that the play serves as a warning because it depicts an imaginary country that resembles today's Russia. The play raises contemporary global issues: the development of science and a machine civilization that is unrestrained by morality, the primacy of the material over the spiritual, and the degradation of society, whose main goal is to achieve the maximum of material wealth.

We present results of research into the tectonic, lithofacies, and geochemical formation conditions of the Erema–Chona oil ans gas accumulation. We characterize present-day structures and their formation history, consider the composition, structure, formation conditions, postdepositional alterations, and porosity–permeability properties of the Osa, Ust’-Kut, Preobrazhenka, Erbogachen, and Upper Chona Horizons, assess the quality of the overlying seals, and describe the technique and results of quantitative estimation of the petroleum potential of pay beds. Modern technologies for the development of oil reserves are also presented, along with geological and economic assessment of hydrocarbon resources of the study object.

The effect of alloying on the properties of highly tempered steels used for production of a range of petroleum pipes is studied. It is shown that an increase in molybdenum content from 0.15 to 0.53% improves the mechanical characteristics of chromium-molybdenum steels tempered at 600–690°C significantly. Alloying with vanadium and niobium facilitates an additional increase in strength properties. The best hardening of steel with 0.32% molybdenum in a highly tempered condition is provided by combined microalloying with niobium and vanadium, although stress corrosion cracking resistance is reduced.

The study introduces a method that evaluates the effectiveness of information resources of an air defense missile system when detecting a hypersonic cruise missile. The method takes into account the dynamic target scattering crossover. The efficiency is evaluated by conducting statistical tests on a simulation model and constructing a vertical section of the detection zone. In this case, the effective target scattering crossover of a hypersonic cruise missile is calculated depending on the parameters of its movement around the center of mass relative to the ground - based detection radar and its line of sight

We present the results of the study of the nonlinear optical response observed in hybrid associates of Azure A dye with Zn0.5Cd0.5S colloidal quantum dots upon exposure to 10-ns pulses of the second harmonic (532 nm) of a Nd3+:YAG laser. It is shown that association enhances the absorption saturation in the dye by a factor of 4.5, which is caused by charge phototransfer between the components of the hybrid associate.

The distribution of the 1H NMR-measurable characteristics of the structural-group composition of crude oils from the Lena–Tunguska basin has been revealed. It has been shown that some distributions are fairly close to the normal one, while others greatly differ from it and are asymmetric. These oils differ from Volga–Urals and Western Siberia oils by a significantly lower aromatics content and a high concentration of radiogenic unsaturated hydrocarbons. The average degree of substitution of aromatics in them is higher than in Western Siberia oils; the distribution maximum for the parameter characterizing this value falls in the region between the two distribution maxima for the Volga–Urals oil. The distribution of the Har,2+/Har,1 ratio is about the same as in the Volga–Urals and Western Siberia oils. A significant difference in the composition between the oils of the Baikit anteclise and the Nepa–Botuoba anteclise has been found.

High-pulse repetition rate lasers allow significant enhancement in the average power of the low-order harmonics generation in isotropic media. We report on the third (343-nm) and fifth (206-nm) harmonics generating in air and different nanoparticle-containing laser-produced plasmas by applying Yb-doped fiber laser delivering 37-fs, 100-kHz, 1030-nm, 0.5-mJ pulses. Different characteristics of these processes (power and density dependences, influence of impeding processes, role of synthesized nanoparticles, variations of the spectral modulation of driving pulses, etc.) are analyzed. We compare the formation of the plasmas on the surfaces of aluminum, carbon, manganese, and titanium bulk species, as well as quantum dots of metal sulfides as the media for low-order harmonics generation, using 250-fs (1030-nm) and 5-ns (1064-nm) heating pulses at different delays between the heating and driving pulses. Average power of about 20 mW was estimated for the third harmonic emission from metal plasmas, with 3 × 1016 UV photons (343 nm) emitted per second.

Luminescence studies of singlet-oxygen photosensitization by methylene blue molecules in various solvents, as well as by hybrid associates of this dye with colloidal Ag2S quantum dots with average sizes of 2.0, 2.4, and 2.7 nm, are performed. The conditions for simultaneous singlet-oxygen photosensitization and detection of the IR luminescence of colloidal Ag2S quantum dots passivated by thioglycolic acid are determined.

The problem of creating effective structures that ensure mutual rotation of the rotor and stator of an electric generator. The wide practical application of counter-rotor wind-electric generators, which provide a significant increase in specific power, is hindered by the disadvantages and low reliability of existing systems for removing electric energy from the windings of a rotating counter-rotor, due to the dry friction mode. It is possible to increase the reliability of the contact removal of electrical energy from the counter rotor (rotating stator) by replacing solid brushes with liquid metal contact groups, which will lead to a certain increase in the resistivity of the contact group, compensated by the contact area of the liquid metal with the contact ring. It is most advisable to use liquid metal contact groups based on gallium, which will raise the permissible temperature limit of operation by about 2 times compared to the achieved level to 275 °C and, thereby, additionally raise the specific power of the electric generator.

The features of nonradiative resonance energy transfer in hybrid associates of colloidal CdS quantum dots (QDs) with molecules of a thiazine dye and J-aggregates of a carbocyanine dye are discussed. The case of an inhomogeneously broadened recombination band of donor (CdS QDs) luminescence is considered. We detected spectral-selective quenching of recombination luminescence of colloidal CdS QDs in association with organic dyes. The maximum of quenching occurs in the region of absorption of the acceptor (organic dye molecule). It is shown using the time-correlated single photon counting technique that the lifetime of the QD luminescence decreases synchronously with the quenching of the luminescence, but only at the wavelengths falling in the region of absorption of the dye. Based on the concept of a donor–acceptor nature of emission of CdS QDs, the dependence of the efficiency of nonradiative energy transfer on the luminescence wavelength is analyzed taking into account the Poisson distribution of its quenchers.

We synthesize colloidal HgSe quantum dots and characterize their nonlinear refraction and nonlinear absorption using a Nd:YAG laser and its second harmonic. The 7.5 nm quantum dots were synthesized using the hot-injection method. The nonlinear absorption (β = 9×10−7 cm W-1) and negative nonlinear refraction (γ = -5×10−12 cm2 W-1) coefficients of colloidal quantum dots were determined using the 10 ns, 532 nm laser radiation. The joint influence of above processes was realized at a higher intensity of probe pulses. In the case of 10 ns, 1064 nm radiation, only negative nonlinear refraction dominated during z-scans of these quantum dots. The studies of optical limiting using two laser sources demonstrated the effectiveness of this process at 532 nm. The role of nonlinear scattering is analyzed. We discuss the mechanisms responsible for the nonlinear refraction processes in colloidal HgSe quantum dots.

The paper presents gaz chromatography–mass spectrometry and 1H- and 13C-NMR data on the composition of hydrocarbon markers and structural-group composition of oils in the Timan–Pechora oil and gas province. The set of samples is subdivided into groups whose oils differ in composition and the distribution of their polycyclic biomarkers. All of the oils show closely similar geochemical characteristics, types of their source organic matter, and thermal maturity. Comparison of oil characteristics (composition of the polycyclic biomarkers) and parameters determined by chromatography–mass spectrometry makes it possible to reveal certain important (and calling for further investigation) relations between the composition of the structural groups of hydrocarbons in the oil fluid and its geochemical characteristics.

Modification of the technique for thickness determination of thin polymer films that are transparent in the visible range with the application of Jamin interferometer is suggested. The films are deposited on glass substrate. The technique is based on measuring the relative shift of interference fringes. The distinguishing feature of the approach is the use of three beams, one of which participates in the formation of the reference signal; the interference-fringe shift is estimated by the analysis of brightness curves.

In Volga−Urals crude oils, an increase in the aromatics content is characterized by a rapid increase in the relative amount of polysubstituted aromatic rings and a generally lower proportion of bi- and polycyclic aromatics, unlike the case of Western Siberia oils. The difference between the oil and gas basins is most probably due to the special features of the source organic matter of the oils. The regional features of the Volga−Urals oils are a relatively weak relationship between the concentrations of mono- and bi- + polycyclic aromatics and a relatively close relation of Σn-Alk to typically uninformative parameter Hβ, which indicate a high uniformity of the composition of saturated cyclic compounds and moieties of hybrid naphthenoaromatic components. In addition, the assumption that (H/C)ar/(H/C)al = const does not hold for Volga−Urals oils. However, the relationships between the main parameters describing total aromaticity (primarily, Car, Har) and n-alkyl structures (primarily, Σn-Alk) are identical for oils from both the basins. The total number of relationships that can be universal for oils from different oil-and-gas basins is fifteen. To estimate Car from 1H NMR data for Volga−Urals crude oils, a linear dependence on the two variables Har and Hα should be used. The expressions obtained to relate the structural-group parameters have made it possible to reveal a number of oils that stands out among the others.

In the past, common media for high-order harmonic generation (HHG) has been atoms and molecules. More recently, clusters, and nanoparticles have been introduced as HHG emitting media. Multi-particle media can enhance HHG yields but have more stringent requirements in determining the optimal parameters. Here, we demonstrate, for the first time, the effective application of 1-3 nm metal sulfide quantum dots (QDs) for harmonic generation in the 20 - 115 nm extreme ultraviolet range. We report on the syntheses, ablation of Ag2S, CdS, and ZnS QDs, and HHG from laser-produced plasmas by using single- and two-color pumps. We compare HHG efficiency from the ablated QDs to that of bulk metal sulfides and show a seven-fold increase in harmonic yields. Further, the study also allows us to understand the effects of QD-contained plasma spreading dynamics on HHG yield.

The features of a nonlinear optical response of the spherical silver nanoparticles with an average size of 20 nm and “core-shell” systems based on them (Ag@SiO2) synthesized using the citrate method in the field of nanosecond pulses of the second harmonic of Nd:YAG laser (532 nm) are studied. It is shown that the presence of a SiO2 shell blocks the saturable absorption that occurs due to the photodestruction of silver nanoparticles. The formation of a positive dynamic lens for the Ag@SiO2, which is not typical for the original silver nanoparticles, was detected. An assumption is made about the capture of photo-excited charge carriers by the SiO2 shell.

The report discloses thermodynamic studies of the semi-closed oxy-fuel combustion combined cycle. The computer simulation and parametric optimization approaches are described in details. The oxy-fuel cycle net efficiency in relationship to the carbon dioxide turbine exhaust pressure and the steam turbine inlet pressure is shown. The power production efficiency reduction is related to the turbine cooling losses is described. It is shown that the semi-closed oxy-fuel combustion cycle maximal net efficiency of 52.5% occurs at the initial temperature and pressure 1400°C and 60 bar at the carbon dioxide turbine exhaust pressure 0.5 bar and the steam turbine inlet pressure 90 bar. The cooling losses consideration leads to the net efficiency of 47.76% that is reached at the carbon dioxide turbine exhaust pressure 1 bar and the steam turbine inlet pressure 90 bar.

Dynamics of the 1Se–1S3/2 exciton in colloidal CdS quantum dots with diameter of 3.1÷4.5nm in gelatin with involvement of localized states was studied by means of femtosecond photoinduced absorption spectroscopy (pump–probe), thermally stimulated luminescence (TSL) observed under permanently excited luminescence. It was found that the bleaching band occurs in the energy region of exciton ground state under excitation by femtosecond laser pulses. The complex dynamics of bleaching recovery is caused by the capture of electron on localized states, found using TSL. The stochastic model describing the dynamics of bleaching recovery is discussed. It is shown that the low efficiency of exciton luminescence is caused by the rapid capture of holes by luminescence centers.

The effect of power limiting for optical radiation at a wavelength of 660 nm with a pulse duration of 10 ms and operation threshold of 2.2 – 3.1 mJ cm-2 is observed in ensembles of colloidal Ag2S quantum dots (QDs). Using the z-scanning method in an open-aperture scheme it is found that the power is limited mainly due to reverse saturable absorption caused by two-photon optical transitions that involve energy levels of Ag2S photoluminescence centres, related to structural impurity defects in colloidal Ag2S QDs. At the same time, the z-scanning in a closed-aperture scheme demonstrates the formation of a thermal dynamic lens.

We have found spectroscopic manifestations of hybrid association in mixtures of CdS colloidal quantum dots with an average size of 2.5–4.2 nm with J-aggregates of pyridinium salt of the 3,3'-di-(γ- sulfopropyl)-9-ethyl-4,5,4',5'-dibenzo-thiacarbocyanine betaine dye that were prepared by the sol–gel method in gelatin. Observed changes of the spectral properties of J-aggregates of dye molecules due to their hybrid association with CdS quantum dots are ensured by steric transformations of dye molecules, which lead to the formation of luminescent trans-J-aggregates. The hybrid association is accompanied by the quenching of the recombination luminescence band of CdS quantum dots (540–640 nm) and by an increase in the luminescence intensity of J-aggregates of dye molecules (670–680 nm). This regularity becomes enhanced with an increase in the ratio of the number of dye molecules to the number of quantum dots [ndye]: [nQD] and in the degree of overlap between the luminescence spectrum of quantum dots and the absorption spectrum of J-aggregates, which indicates that there is a resonant nonradiative transfer of the electronic excitation energy from recombination luminescence centers in CdS quantum dots to trans-J-aggregates of dye molecules conjugated to them.

The character of the distribution of 16 main NMR-measurable parameters of the structural-group composition of Volga–Urals crude oils has been assessed. It has been shown that the distributions quite significantly differ from the normal distribution; they are in general asymmetrical and essentially different. Total aromaticity and the amount of n-alkyl structures in oils of the major stratigraphic plays are on average the same, although there are differences between the northern, central, and southern parts of the oil-and-gas basin. Regarding the concentration of unsaturated hydrocarbons, there are differences between both the plays and territories. Similarities and dissimilarities between the West Siberian and Volga–Urals basins in distributions have been revealed. Some features observed for Western Siberia oils have to be other in the Volga–Urals basin. Upper Carboniferous and Lower Permian carbonate reservoirs in the northeast of the basin have been found to contain oils with a uniquely high concentration of aromatics that evidently differ in composition from those normally present in crude oils. The advantages of interval plots of probability density over histograms for comparing the distributions have been demonstrated. Using the particular material, it has been shown that the Student t-test conventionally used to compare average values for oil groups leads to false conclusions. To determine systematic shifts between distributions, it is necessary to use the Mann–Whitney test and compare the medians of distributions.

TiO2/QDCdS heterostructure was synthesized by depositing preliminarily prepared cadmium sulphide (CdS) quantum dots onto microcrystalline rutile films and then their absorption and luminescence spectra were studied. It was observed that photon processing of the TiO2/QDCdS heterostructure with high-power light fluxes of xenon flash lamps contributes to the generation of the conditions necessary for the separation of nonequilibrium charge carriers.

In the conditions of economic sanctions and food embargo in Russia, the issue of import substitution has become acute. Studies are becoming relevant, which improve the production process of hops. Currently, many enterprises use industrial dryers with high performance. The aim of the study is to increase the efficiency of drying hops with the maximum possible reduction of energy costs. The introduction of innovations should be preceded by an analysis of the existing technology of drying hops. Object of research - hop samples taken during and after drying, as well as an industrial dryer. Working measurements were carried out in threefold repetition. These included determining the temperature and humidity of the drying agent as well as the humidity of the hops. The results of studies have shown that it is possible to achieve significant energy savings in the process of drying hops. This is the scientific novelty. Based on the results, several ways to achieve savings are proposed. To do this, it is necessary to accelerate the movement of the mass of hop cones and optimize the ventilation system. On the basis of this, the possibility of modernizing the duct system to increase the productivity of the dryer is proposed.

The methods of controlling the charge state of nitrogen–vacancy centers using pulsed infrared laser field are studied. The effect of radiation intensity at a wavelength of about 1 μm on the ionization of these color centers was shown. The obtained results can be useful for multiphoton microscopy of biological objects, high-resolution microscopy and sensory applications.

We investigate the energy structure of colloidal CdS nanocrystals by measuring the UV–vis absorption spectra. Nanocrystals were synthesized by sol–gel method in a gelatin matrix in the size range from 2.5 to 3.9 (70.2) nm. In order to interpret the UV–vis absorption spectra we calculate the energy spectrum of electron quasi-stationary states using the model of open nanocrystal as well as the hole stationary spectrum in a two-band approach. It is shown that the main contribution to the absorption spectrum is made by interband transitions 1S3/2-1Se and 1P3/2-1Pe, and its shape is determined by the size distribution of nanoparticles. For this system the estimated values of the effective masses of the heavy hole and light hole are 1.44m0 and 0.28m0, respectively.

The electron beam domain patterning of MgO-doped congruent lithium niobate (LN) single crystals covered by electron beam resist layer were studied for various layer thicknesses and electron accelerating voltages. The obtained domain patterns were divided in four types. The increasing of the domain structure quality under presence of the resist layer on irradiated surface was confirmed. This effect was attributed to high concentration of the electron traps in resist, which localized incident electrons in limited volume over LN surface and formed effective electrode. The voltage dependence of space charge localization relative to the LN surface was studied by computer simulation.

Luminescence properties of hybrid associates of semiconductor colloidal CdS quantum dots (QDs) with an average diameter of 2.5 nm and methylene blue (MB+) cations were investigated. Their photoluminescence spectra, excitation spectra and luminescence decay spectra recorded using the time-correlated single photon counting techniques were analyzed. The increase of efficiency of MB+ fluorescence at 405 nm excitation was found. It corresponds to the absorption region of CdS QDs. When [ n CdS QDs ] : [ n MB + ] concentrations ratio changes from 100:1 to 1:3 for associates, then a decrease in the intensity of CdS QDs luminescence band (580 nm) and its increase for MB+ band (674 nm) were observed. At the same time it was found that the average lifetime of CdS QDs luminescence is shortened and the lifetime of MB+ luminescence becomes significantly longer. It was concluded that dynamic quenching due to nonradiative resonance energy transfer takes place. The efficiency of this process was estimated and the corresponding rate constant was calculated. It is 5.6 × 10 7 to 8.6 × 10 7 s − 1 .

An experimental demonstration of a subcarrier-wave quantum cryptography system with superconducting single-photon detectors (SSPDs) that distributes a secure key in a single-mode fiber at distance of 25 km with a bit rate of 800 kbit/s, a distance of 100 km with a bit rate of 19 kbit/s, and a distance of 200 km with a bit rate of 0.18 kbit/s is described.

We demonstrate a fiber-optic source of random numbers in which random-number generation (RNG) is implemented via an inherently quantum process—detection of correlated photon pairs produced by spontaneous four-wave mixing (FWM) inside an optical fiber. The detection times of individual photon pairs, generated in our RNG scheme via phase-matched FWM in a highly nonlinear photonic-crystal fiber with a suitable dispersion profile, are converted into megabit-size binary sequences, serving as strings of random numbers. The randomness of these bit strings is verified by the National Institute of Standards and Technology Statistical Test Suite. We identify FWM regimes in which mode-locked short-pulse laser sources can provide a high peak power needed to drive photon-pair generation in optical fibers without an excessive loss of randomness due to unwanted patterns in the RNG photon-pair output.

Four-wave mixing (FWM) of ultrashort laser pulses in a highly nonlinear photonic-crystal fiber is shown to provide a multimodal source of broadband quantum states of light. In the regime of low pump powers, generation of two-photon states and heralded single photons with a bandwidth up to ≈6 THz is demonstrated within an FWM-sideband tunability range of ≈55 THz. In the modality of heralded single-photon generation, three-detector measurements of the conditional second-order correlation function reveal a strong antibunching in the signal-photon channel, with more than 99.2% of the signal counts identified as truly single-photon states. At high pump powers, two-detector signal-idler correlation function measurements indicate broadband bright squeezed vacuum generation.

To analyze postoperative complications of totally implantable central venous port system (TIPCVP) deployment and develop methods of their prevention.The study involved 43 patients who underwent TIPCVP implantation through right-sided jugular access and 3 patients with migration of the catheter transferred to the Domodedovo Central City Hospital.There were four perioperative and one early postoperative complication. None of the complications was the reason for removal of TIPCVP. Pinch-off syndrome occurred in two patients who were operated in other hospitals and a catheter was inserted through the right subclavian vein.Injury of the carotid artery and pneumothorax can be avoided by ultrasound navigation during internal jugular vein puncture. Catheterization of the internal jugular vein is useful to avoid pinch-off syndrome. Migration of the catheter is successfully cured by endovascular methods.Цель исследования - на основании анализа осложнений имплантации центральной венозной порт-системы (ЦВПС) разработать методы их профилактики и лечения. Материал и методы. Обследованы 43 больных, которым в Домодедовской центральной городской больнице (ДЦГБ) выполнена имплантация ЦВПС правосторонним югулярным доступом, и 3 больных с миграцией катетера, переведенных в ДЦГБ. Результаты. В группе больных, оперированных в ДЦГБ, возникли 4 периоперационных и 1 раннее послеоперационное осложнение. Ни одно осложнение не послужило поводом к удалению ЦВПС. Синдром pinch-off встретился только у 2 больных, оперированных в других медицинских учреждениях, которым катетер установили через правую подключичную вену. Выводы. Повреждения сонной артерии и пневмоторакса можно избежать, используя ультразвуковую навигацию при пункции внутренней яремной вены. Катетеризация внутренней яремной вены позволяет избежать развития синдрома pinch-off. Миграцию катетера успешно излечивают эндоваскулярными методами.

Using the spectral methods of induced absorption, luminescence, and photostimulated luminescence flash, we have experimentally investigated processes of decay of electronic excitations in CdS colloidal quantum dots and in CdS/ZnS “core-shell” systems synthesized in gelatin by the sol-gel method. It has been shown that the decay of electronic excitations in colloidal quantum dots of this type is predominantly related to a fast localization of nonequilibrium charge carriers on surface defects and their subsequent recombination during times on the order of units and tens of picoseconds. The passage to core-shell systems eliminates, to a large extent, surface defects of the core, some of which are luminescence centers. However, upon using the sol-gel synthesis, a noticeable fraction of luminescence centers are formed in the interior of the CdS quantum dot, which, as well as in the case of CdS/ZnS systems, ensures localization of exciton, blocks its direct annihilation, and maintains recombination radiation.

The characteristics of the residual stresses arising in float-glass production are presented. The forms, causes, magnitude and direction of the stresses are described. The condition for off-cut breakage is derived mathematically. Modeling with ANSYS Structural Ver. 14.0 is used to obtain the stress pattern when the breaking bar is raised and the critical parameters for which glass losses occur during cutting are determined.

We have analyzed the possibilities of using the phenomenon of photostimulated luminescence flash for optical diagnosing of energy levels of structural and impurity defects of semiconductor crystals and nanostructures. New data on the spectra of deep localized states associated with adsorbed few-atom clusters Znn on the surface of ZnS; clusters Cdn, Cun, and Agn on the surface of CdS; and clusters Agn on the surface of AgBr(I) have been presented, as well as results of investigation of photostimulated assembling processes of few-atom clusters on the surface of crystals using this phenomenon. We are the first to show the potential of the luminescence flash technique for studying the mutual arrangement of the levels of dye molecules and the bands of the crystal on the surface of which they are adsorbed, as well as of the spectra of localized states in colloidal CdS semiconductor quantum dots.

Correlations between frequencies of the Raman-active A(TO) and E(LO) phonons and the layer thickness ratio in the AlN/GaN superlattices are determined. Theoretical frequency-structure relations are derived by using the dielectric continuum model. It is found that the elastic strains which inevitably arising in the layers upon SL growth affect frequencies of the most Raman-intense polar modes insignificantly. The obtained frequency-structure relations agree well with available experimental data. These results confirm efficiency of the Raman spectroscopy for a fast nondestructive structure characterization.

The study investigated the effects of climatic (depth and density of snow cover; air temperature; precipitation), biotic (land and avian predators), and human-caused (agriculture, traffic, and hunting) factors on the population dynamics of the European hare in some habitats.

This paper describes an absolute ballistic laser gravimeter of a new generation developed at the Institute of Automation and Electrometry, Siberian Branch of the Russian Academy of Sciences. The device is intended for use under field conditions and has small dimensions and weight. The light source in the gravimeter interferometer is an optical standard with a wavelength λ = 532 nm consisting of a traveling-wave Nd: YAG laser with intracavity frequency doubling and with a stabilization system for the saturated absorption resonances in molecular iodine. The instrumental standard error in measuring the absolute gravity by the gravimeter does not exceed ±5 · 10−8 m/s2 (or 5 µGal).

The optical limiting properties of alloyed Cd0.5Zn0.5S quantum dots associated with erythrosine dye are analyzed using 532 nm, 40 ps pulses. We show that joint influence of saturable absorption, reverse saturable absorption and two-photon absorption cause the optical limiting of 532 nm radiation at the pulse energies exceeding 1 mJ. The nonlinear refraction and nonlinear absorption of these quantum dots associated with different organic dyes were studied using 1064 nm and 532 nm radiation. The nonlinear refraction index and nonlinear absorption coefficient of Cd0.5Zn0.5S quantum dots were measured at λ = 1064 nm to be 2 × 10-13 cm2 W-1 and 1.2 × 10-8 cm W-1, while the reverse saturable absorption of Cd0.5Zn0.5S quantum dots and erythrosine at λ = 532 nm was almost two orders larger. The potential applications of these quantum dots for high-order harmonic generation are discussed.