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Double-walled carbon nanotubes (DWNTs), often regarded as the simplest one-dimensional (1D) van der Waals moiré superlattices, are the ideal structures to explore the interlayer coupling, including mechanical and electronical coupling, at the nanoscale in 1D systems. By combining spatial modulation spectroscopy (SMS) and resonant Raman scattering (RRS) experiments on well-identified individual free-standing DWNTs with the calculations of their optical absorption by using the recursion method with non-orthogonal tight-binding (NTB) basis functions, we are able to unambiguously assign the nature, namely mirror transition or cross transition, of each optical transitions in DWNTs. Our study identifies and allows to determine the conditions of the mixing of the electronic states leading to the appearance of cross transitions in the optical absorption of DWNTs, beyond of the so-called Koshino's criteria previously derived. On the other hand, the striking behavior of the resonant excitation profile (REP) of the Raman active modes around the cross transition reveals the strong sensitivity of the modes intensity on the electronic interlayer coupling in DWNTs, emphasizing the relevance of Raman spectroscopy for studying the electronic and mechanical coupling at the nanoscale., We acknowledge the Dr. T. X. Tinh for the synthesis of individual nanotubes. HNT, RP, AAZ, JLS and MP acknowledge financial support by the ANR GAMBIT project, grant ANR-13-BS10-0014 of the French Agence Nationale de la Recherche. The TEM studies were performed in the Laboratorio de Microscopias Avanzadas (LMA), Universidad de Zaragoza (Spain). R.A. acknowledges support from Spanish MICINN (PID2019-104739 GB-100/AEI/10.13039/501100011033), Government of Aragon (projects DGA E13-20R (FEDER, EU)) and from EU H2020 “ESTEEM3” (Grant number 823717). VNP acknowledges financial support for NTB calculations from the National Science Fund of Bulgaria under grant KP-06-N38/10 from December 06, 2019.

A 2D mathematical model is proposed for the modification of an iron-based alloy with refractory nanosized particles. Numerical simulation of the processes during the modification of the surface layer of the substrate metal using the energy of a laser pulse has been carried out. Within the framework of the proposed model, the processes of heating and melting of metal on a substrate covered with a layer of nanosized refractory particles penetrating into the molten metal, convective heat transfer in the melt, and solidification after the end of the pulse are considered. Metal melting is considered in the Stefan approximation, and when the melt is cooled, the model of heterogeneous nucleation and subsequent crystallization is used. The fluid flow is described by the Navier-Stokes equations in the Boussinesq approximation. The distribution of nanoparticles in the melt is modeled by moving markers. Based on the results of calculations, the mode of pulsed laser action is determined, in which a flow is formed for a homogeneous distribution of particles of the modifying substance in the presence of a surfactant in the metal. The volume of the solid phase formed around the nucleus determines the size of the grain structure in the solidified alloy. The liquidus temperature changes depending on the concentration of dissolved carbon in the melt. In the numerical simulation of the solidification of the surface layer of the metal, it was found that the conditions of nucleation and crystallization differ significantly in the volume of the melt. It is determined that the duration of nucleation in a supercooled melt is several tens of microseconds. The maximum number of crystallization centers occurs in areas where heat removal occurs most rapidly. With the growth of the solid phase in the melt and the release of the latent heat of crystallization, the value of supercooling decreases, the nucleation stops and the number of formed crystallization centers does not change further. The distribution of the dispersion of the crystal structure over the volume of the melted metal is estimated. It was found that as the melt cools, sequential-volume crystallization occurs.

Применена технология глубокой сверточной нейронной сети к обработке аудиофайлов, в частности для классификации амплитудно-частотных характеристик аудиосигналов. Сопоставление аудиофрагментов между собой сведено к решению задачи верификации дикторов. В качестве набора данных для обучения глубокой сверточной нейронной сети собрана большая репрезентативная выборка аудиосигналов и дополнена удовлетворяющим требованиям набором данных Free Music Archive, который содержит свободно распространяемые аудиозаписи музыкальных произведений. Для предотвращения переобучения предсказательной модели применены четыре типа аугментации, в том числе гауссовый шум, реверберация, изменение частоты основного тона, изменение темпа аудиосигнала. В качестве предсказательной модели была взята архитектура CQT-Net. Для сравнения векторов признаков используется косинусное сходство. Качество верификации было протестировано на двух выборках, состоящих из 1500 аудиозаписей, которые не использовались во время обучения. Построены Det-кривые для наборов данных, в том числе тестовых с измененным темпом и с измененным питчем. В роли метрики качества модели использован равный уровень ошибок (коэффициент Equal Error Rate). Оценена вероятность выявления наиболее применяемых искажений аудиосигналов в амплитудно-частотной области (не менее 92 %), что говорит о надежности полученной системы., This paper studies the application of deep convolutional neural networks for the processing of audio files, particularly for classifying amplitude-frequency characteristics of audio signals. The mapping of audio fragments to each other is reduced to verifying objects by their representation. A large representative sample of audio signals was collected and supplemented with a satisfying Free Music Archive dataset to produce a dataset for training a deep convolutional neural network. The CQT-Net architecture is taken as a predictive model with cosine similarity being used to compare feature vectors. Four types of augmentation, including Gaussian noise, reverberation, change in pitch frequency, and change in tempo of the audio signal, are used to prevent retraining of the predictive model. The verification quality of the predictive model is tested on two separate datasets consisting of 1500 audio recordings excluded from the training dataset. Detection error tradeoff curves are plotted for all datasets, including testing ones with a changed pace and with a changed "pitch." Equal Error Rate is used as a model quality metric. The probability of identification of commonly used distortions of audio signals in the amplitude-frequency domain is evaluated to be higher than 92%. It signifies the reliability of the developed model.

Methylene blue is a phenothiazine dye that is widely used in medicine and clinical trials for the treatment of Alzheimer's disease. One of the factors of the unique therapeutic effect of methylene blue is its redox properties, allowing implementation of alternative electron transport - the dye accepts electrons from reducing equivalents in the mitochondria and transfer it them to other components of the respiratory chain or molecular oxygen. Azure I, an N-dimethylated metabolite of methylene blue, is potentially a more effective compound than methylene blue, but its ability for alternative electron transport has not been studied. We have shown that azure I, unlike methylene blue, is unable to restore the membrane potential in isolated mouse brain mitochondria, inhibited by rotenone and, therefore, is unable to perform bypass of the respiratory chain Complex I. Moreover, the addition of azure I does not affect the rate of mitochondrial respiration in contrast to methylene blue, which increases the rate of non-phosphorylation respiration. At the same time, both dyes stimulate an increase in H2O2 production. As a consequence, only methylene blue is capable of alternative electron transport, while azure I does not produce complex I bypass. This limits its therapeutic application only as a mitochondrial-targeted drug, but not as a substance with a potentially powerful antidepressant effect.Metilenovyĭ siniĭ — fenotiazinovyĭ krasitel', kotoryĭ shiroko primeniaetsia v meditsine i na dannyĭ moment prokhodit klinicheskie ispytaniia dlia lecheniia bolezni Al'tsgeĭmera. Odnim iz faktorov unikal'nogo terapevticheskogo éffekta metilenovogo sinego iavliaiutsia ego okislitel'no-vosstanovitel'nye svoĭstva, kotorye pozvoliaiut emu prinimat' élektrony ot vosstanovitel'nykh ékvivalentov v mitokhondriiakh i peredavat' na drugie komponenty dykhatel'noĭ tsepi ili molekuliarnyĭ kislorod, to est' osushchestvliat' al'ternativnyĭ transport élektronov. Azur I — N-demetilirovannyĭ metabolit metilenovogo sinego — po riadu pokazateleĭ potentsial'no bolee éffektivnoe soedinenie, chem metilenovyĭ siniĭ, no ego sposobnost' k al'ternativnomu transportu élektronov ranee ne byla izuchena. My pokazali, chto azur I v izolirovannykh mitokhondriiakh mozga mysheĭ, v otlichie ot metilenovogo sinego, ne sposoben vosstanavlivat' membrannyĭ potentsial, kotoryĭ byl ingibirovan rotenonom i, sledovatel'no, ne sposoben osushchestvliat' shuntirovanie I kompleksa dykhatel'noĭ tsepi. Krome togo, dobavlenie azura I ne vliiaet na skorost' dykhaniia mitokhondriĭ v otlichie ot metilenovogo sinego, kotoryĭ uvelichivaet skorost' ne stimulirovannogo ADP dykhaniia. Pri étom oba krasitelia vyzyvali uvelichenie produktsii H2O2. Takim obrazom, tol'ko metilenovyĭ siniĭ sposoben osushchestvliat' al'ternativnyĭ transport élektronov, a ego demetilirovannaia forma — azur I — ne proizvodit shuntirovanie kompleksa I, chto neskol'ko ogranichivaet ego terapevticheskiĭ potentsial kak mitokhondrial'no-napravlennogo preparata, no ne stavit pod somneniia ego antidepressantnye svoĭstva.

The article discusses the uniform model of representation heterogeneous data hydrometeorological observations from international codes used for transmission. Physical this model simply shows the machine representation of aggregate tables with variable-length strings. A list of keys creates for all tables and this list of keys allows to carry out a targeted search for the required data.

Cytogenetic peculiarities during the passing of meiosis were studied in anthers of 7 interspecific F1 hybrids obtained by crossing annual wild species (Helianthus annuus, H. praecox, H. argophyllus) with the cultivated sunflower. The hybrids derived from H. annuus and H. argophyllus were characterized by a low frequency of aberrations (6.5-8.6%), which gives evidence of a good balance of the chromosome complex of these hybrids. The hybrids derived from the crosses between H. praecox and the cultivated sunflower were considerably less stable because of a high frequency of aberrations in meiosis (29.6-50.0%).

The approach allows to organize distributed storage of large amounts of diverse data in order to further their parallel processing in high performance cluster systems for problems of climatic processes analysis and forecasting. For different classes of data was used the practice of using meta descriptions - like formalism associated with certain categories of resources. Development of a metadata component was made based on an analysis of data of surface meteorological observations, atmosphere vertical sounding, atmosphere wind sounding, weather radar observing, observations from satellites and others. A common set of metadata components was formed for their general description. The structure and content of the main components of a generalized meta descriptions are presented in detail on the example of reporting meteorological observations from land and sea stations.

Experiments conducted on the SOM facility at the Russian Federal Nuclear Center–VNIITF, concerning the turbulent mixing induced by the Rayleigh–Taylor instability in a three-layer system of immiscible liquids are described. The fluids are contained in a small tank 6.4 cm × 5.4 cm × 12 cm, which is accelerated vertically downward by a gas gun. The mixing layer evolution was imaged by seeding one of the fluids with particles and using a bidirectional light sheet method (refractive index matching was used to minimize measurement errors). Experiments were performed for two different accelerations (g = 350 g0 and g = 100 g0, where g0 = 980 cm/s2, and the acceleration decreases with distance traveled), and with aqueous solutions of glycerin and benzene (with density ratio 1.6). The lower, middle, and upper layers were a sodium hyposulfite–glycerin solution, a water–glycerin solution, and benzene, respectively. The glycerin solution was seeded with particles. The principal objective of the experiments was to obtain the distribution of fluid particle sizes arising from the mixing of the immiscible fluids.

The paper presents results of numerical simulation of convective flows which exist in Ge and Si melts while growing crystals in Czochralski configuration in a rotating heat field of second order axial symmetry (L 2 ). The numerical simulation is based on the solution of non-stationary three-dimensional Navier–Stokes equations and heat-transfer equations in Boussinesq approximation. The results showed that heat field rotation makes possible an efficient mixing of molten material without any mechanical tools. Trajectories of closed toroidal flows having the azimuthal component of velocity vector have been simulated in the melt. We demonstrate a novel heating concept provided by a contact-free control over heat–mass transfer processes in a medium of crystallization.

SUMMARY The genetics of anodal esterase (Est), cathodal esterase (cEst), cathodal acid phosphatase (cAcp) and malate dehydrogenase (Mdh) has been studied in mature seeds and leaves (genetics of cAcp and Mdh has not been studied in leaves) of sunflower (Helianthus annuus L.). A total of ten loci (four loci of anodal esterase, two loci of cathodal esterase, three loci of malate dehydrogenase and one locus of cathodal acid phosphatase) have been identified and described. Five esterase loci (Est1, Est2, Est3, Est4, cEst5), three malate dehydrogenase loci and one locus of cathodal acid phosphatase are expressed in seeds. Three esterase loci (Est2, cEst5 and cEst6) are expressed in leaves. The analysis of linkage between these loci has been made. Two linkage groups have been found. The sequence of the loci in the first linkage group was Mdh2-Est1- Est2-Est3-cEst5. In the second linkage group it was Est4-cAcp1. Linkages have been analyzed between three isoenzymatic loci expressed in leaves and between two loci controlling morphological traits (branched stem and male fertility restoration). The linkage between morphological traits and isoenzymatic loci has not been revealed. It has been revealed in Br-Rf pair.

At the installation SOM, the experimental study of the impulse acceleration influence on the behavior of the turbulized layer obtained as a result of Rayleigh–Taylor instability (RTI) action on the system of two different density liquids with the density ratio n = 3, has been performed. After application of impulse acceleration the systems were moving according to inertia, and by using the light method the coordinates of penetration of the heavier liquid into the lighter one and vice versa were determined. The liquids studied were placed inside the ampoule that had internal working sizes (54 × 64 × 120) mm3. There were initial accidental perturbations like a rough solid surface at the interface and the width of the initial perturbation zone was L0 = 2.3 mm. The moving ampoule blow against metal plates created the impulse acceleration. The relative impulse acceleration was δg/g11 = 22.2–66.6 where g11 is the ampoule acceleration before the impact, the impulse duration was varied from 0.27 ms to 0.096 ms. The results concerned with the turbulized layer extension after the impulse acceleration action were obtained.

Behavior of the turbulized mixtures at the stage of their inertial motion (with removed acceleration) has been studied. Turbulized mixtures were obtained at the contact boundary of two different density fluids as a result of the Rayleigh–Taylor instability (RTI) development. At some instant of time t*, the acceleration sign was changed and conditions for the mixture separation were created. Then at the instant of time t**, the acceleration was removed and the turbulized mixture continued to move under force of inertia. Experiments have been performed at the installations EKAP and SOM. At the stage of inertial motion, the average density distribution of substance in the mixture region and the width of the turbulized mixture region have been obtained. The data on the mixture region expansion at the stage of inertial motion have been obtained as well.

The spectrum of collective modes in the antiferromagnetic state of the two-dimensional weakly repulsive Hubbard model is calculated by means of path integration with the use of “fast” and “slow” variables and the Hubbard-Stratonovich transformation both in the Ginzburg-Landau region and near zero temperature.

We report micro-Raman spectra obtained from R 2 Ba 2 Ti 2 Cu 2 O 11 (R = Nd, Gd) and Gd 2 CaBa 2 Ti 2 O 12 ceramic samples. The analysis of the spectra was performed using the similarity between the investigated structures and related layered pure copper and titanium oxides. The assignment of the observed lines to definite atomic vibrations is supported by lattice-dynamics calculations, based on a shell model. The calculated frequencies for the IR-active modes are also presented. We stress that in contrast to Gd 2 CaBa 2 Ti 2 Cu 2 O 12 , where the ceramics consist of optically anisotropic plate-like microcrystals, in the case of the quadruple perovskites R 2 Ba 2 Ti 2 Cu 2 O 11 the microcrystals are isotropic, probably due to the fine twinning, rendering it impossible to obtain polarized Raman spectra along different crystal directions.

A large-scale study of coal gasification by steam and coal cooking processes under an electron beam with a power of up to 80 kW has been carried out. The product formation rates, energy consumption and energy storage in products were determined. The energy efficiencies of the processes were estimated. Some energy problems and a comparison with traditional methods of coal conversion have been considered.

We relate partition functions of spin systems for arbitrary spin s to partition functions of fermion systems. A simple diagram technique with s -dependent Matsubara frequencies is found. We indicate also a similar procedure for su(3) models.

The earlier suggested superconductive state in the two-dimensional repulsive Hubbard model is investigated. Cooper pairing in this state arises due to an effective attraction of fermions in channels with odd angular momenta. It is shown that superconductivity can exist only if one of the Van Hove saddle points of the quasiparticle energy lies near the Fermi level. Equations are obtained for the phase transition curve and for the order parameter in the superconductive state. The optimal relative position of the Van Hove point and the Fermi level corresponding to the maximal critical temperature is found. It is argued that two superconductive modes with threefold spin degeneration and, in principle, with different values of the gap parameter can exist in the model under consideration.

A phase operator problem for the one-dimensional Bose-oscillator is considered. The basic construction of the phase and occupation number variables in the r-dimensional subspace of the oscillator's functions is given. Two possibilities for the r → ∞ limit are discussed.

Recent experiments measuring the clapping mode frequency in 3 He-A are in good agreement with the Brusov-Popov theory, constructed by a path integral method. Here a complete set of equations, which describe the collective excitations (CE) in 3 He-A in arbitrary magnetic fields, is first obtained taking into account the CE damping, by using the same method. These equations are solved for small fields and zero CE momenta K , and the linear Zeeman effect for the clapping (cl) and pair-breaking (pb) modes is obtained: a three-fold linear splitting of these modes which could be observed in zero sound experiments. The influence of magnetic fields on CE damping is investigated too.

It is shown that an effective attraction arises between electrons with momenta near saddle Van Hove points in the two-dimensional repulsive Hubbard model. The formula for Tc is obtained and the type of Cooper pairing near Tc is determined which may be called “the superposition of pairings with odd angular momenta” (approximately this is p-pairing). The problem of competition between superconductivity and ferromagnetism is discussed.

The reconstruction intraseasonal variations of tree radial growth method of restoration is offered and approved on the base of a new condition of dispersion causality and the developed mathematical model for wood density in tree-ring radial section where the tree radial growth is subject to the multifactorial influence of the environment. As against traditional dendroindication the new method provides continuous on a season and more exact estimation of bioclimatic changes.

A method is developed for the manifestly covariant quantization of gaugeinvariant fields by means of a functional integration. It is shown that for the fields with non-Abelian gauge groups (the Yang–Mills and gravitational fields) fictitious particles appear naturally in the diagram technique, which are not present in the initial Lagrangian. An appearance of these particles restores the transversality of scattering amplitudes and the unitarity of the S-matrix.

Climate is the main factor limiting capability of forest and communities in many areas of the world. By means of tree-ring analysis it is possible to make a reconstruction of many important climatic and hydrological characteristics. This paper describes a method of determination of climatic parameters with the help of tree-rings analysis.

A classical scheme for solving the boundary-value problem for a system of Maxwell's equations in a spherically stratified model of the Earth-ionosphere waveguide has been known since the beginning of the 20th century, and implies the following. The elementary electric or magnetic dipoles are usually assumed as emitters. In each of these cases the Hertz potentials are introduced, which satisfy partial differential equations with separable variables. Solutions to this equations are sought either in the form of a series in terms of eigenfunctions of the angular operator or in the form of a series in terms of eigenfunctions of the radial operator. The transition from one series to the other is accomplished through the Watson transformation. Attempts to generalize this scheme to the case of more sophisticated waveguide and emitter models led the author to the conclusion that the scheme should be modified. To elucidate the essence of the problem, a very simple model is considered. Unlike the classical scheme, we abandoned the idea of introducing any potentials, and formulated boundary-value problems for the components of fields. The objective of this paper is to devise a reasonably rigorous mathematical scheme for seeking the formal expressions for solving a system of Maxwell's equations.

An apparatus intended for investigating the dynamics of gas-bubble compression was used to perform static and dynamic tests. Static tests were used to measure the deflection of the membrane shaper under various static pressures in liquids, while dynamic tests were used to measure the velocity of one of the membrane shapers under quick relief of pressure in the gap between the rupture membrane and the second membrane shaper. Both dynamic and static tests were performed under pressures up to 30 atm. A comparison of the experimental and the calculated data was made.

Two experimental apparatuses were developed to investigate gas-bubble compression dynamics. Both apparatuses were manufactured; the main components and rupture membranes of these apparatuses were tested. This paper describes the design of the two apparatuses and identifies the physical and functional aspects of the experimental setup.

This paper gives experimental results on the geometry of a gas bubble upfloating in a liquid for the case of a single exposure to a pressure pulse. An apparatus operated in the mode of rarefaction–compression wave generation in a liquid was used for experiments with two media: gas–air and liquid–water. Geometrical sizes were registered with the help of the optical shadow method. Experimental results were used to study how the evolution of dimensionless volume of the upfloating gas bubble depends on time (V(t)/V0) in the case of exposure to a variable dimensionless pressure field in time P(t)/P0.

Thermoradiation processes for hydrogen and carbon monoxide production from water vapor and CO2 are discussed. The experiment was conducted in one-pass flow system metal equipment, using an electron accelerator as a radiation source (Ee = 3 MeV). The radiolysis parameters were as follows: dose rate (δ) ≈ 0.1–20 W/l, the reagent-radiation contact time (τ) 0.5–100 s, the temperature (T) up to 700°C. The functional dependence of the products radiation yield is determined: G = f(T, δ, τ), and the steady-state concentrations of H2 and CO are obtained. The maximum values are G(H2) = 8 and G(CO) = 13, corresponding to 20 and 40% radiation energy-product energy conversion, respectively. The steady-state concentration of hydrogen is ∼ρδ, and the time of the linear H2 formation τ 0 ∼ δ − 1 2 . The results obtained have allowed us to determine optimal parameters of the process and to estimate the relative efficiencies of chemonuclear and electrochemical (plasmolysis, electrolysis) methods of production of H2 and CO using nuclear piles.

The possibility is discussed of applying the method of functional integration to the description of a heavy atom. Passage in the functional integral to a new variable - the field of the electric potential - makes it possible to construct a modified perturbation theory for computing the Green function whose poles give the energy and damping of collective levels.

A review dedicated to the contemporary methods of quantization of the gravitational field. In view of possible applications to elementary particle theory, the authors consider only asymptotically flat gravitational fields. The basis of the exposed method of quantization is the method of quantization of gauge fields in the functional integration formalism. The main result is the formulation of covariant rules for a diagrammatic perturbation theory. Its elements are the lines representing gravitons and the vertices of graviton-graviton interaction, as well as the lines and interaction vertices of fictitious vector particles ("Faddeev-Popov ghosts") characteristic for the theory of gauge fields. The expressions for the propagators and vertex functions are given explicitly. It is shown that the presence of fictitious particles in the covariant diagram technique guarantees the unitarity of the theory and the agreement between the covariant quantization with the canonical quantization. The bibliography contains 44 entries (54 names).

The Bose spectrum of superfluid solutions 3He4He is investigated in the case of p-pairing of Fermi particles. Both three-dimensional and two-dimensional models are considered. It is shown that the Bose-Fermi interaction changes the sound velocities in both subsystems. The other collective modes (17 in the 3D-model and 11 in the 2D-model) remain almost unchanged.

A strong electric field leads to anisotropy of the spectrum of elementary excitations of superfluid helium and affects the hydrodynamics, reducing the superfluid flow perpendicular to the field.

IN this paper we are considering the error information realized in the translator TA-1M at the linguistic level in a form convenient for reception. The translator TA-1M is an improved version of the translator TA-1, called in [1] a programming program. In comparison with the Ta-1, the TA-1M composes programs of the highest quality both in speed of action and also in respect of memory economy. There are debugging means: a debugging method of carrying out the working program, the outputting of error information to the alphabetic-digital printer (ADP) etc. The error information is produced both at the stage of translating the original program, and on executing the working program. The information can be extracted by any alphabet -digital printer (ADP) present on the computer, in the form of phrases which explain the cause of the error or give recommendations for its removal, parts (segments) of the original program containing the errors of the identifiers, their values etc.