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Ti2Nb2O9 with a tunnel-type structure is considered as a perspective negative electrode material for Li-ion batteries (LIBs) with theoretical capacity of 252 mAh g-1 corresponding to one-electron reduction/oxidation of Ti and Nb, but only ≈160 mAh g-1 has been observed practically. In this work, highly reversible capacity of 200 mAh g-1 with the average (de)lithiation potential of 1.5 V vs Li/Li+ is achieved for Ti2Nb2O9 with pseudo-2D layered morphology obtained via thermal decomposition of the NH4TiNbO5 intermediate prepared by K+→ H+→ NH4+ cation exchange from KTiNbO5. Using operando synchrotron powder X-ray diffraction (SXPD), single-phase (de)lithiation mechanism with 4.8% unit cell volume change is observed. Operando X-ray absorption near-edge structure (XANES) experiment revealed simultaneous Ti4+/Ti3+ and Nb5+/Nb4+ reduction/oxidation within the whole voltage range. Li+ migration barriers for Ti2Nb2O9 along [010] direction derived from density functional theory (DFT) calculations are within the 0.15-0.4 eV range depending on the Li content that is reflected in excellent C-rate capacity retention. Ti2Nb2O9 synthesized via the ion-exchange route appears as a strong contender to widely commercialized Ti-based negative electrode material Li4Ti5O12 in the next generation of high-performance LIBs.

Samarium-sodium double sulfate crystalline hydrate NaSm(SO4)2·H2O was obtained by the crystallization from an aqueous solution containing equimolar amounts of ions. The anhydrous salt of NaSm(SO4)2 was formed by a thermally induced release of the equivalent of water from NaSm(SO4)2·H2O. The kinetic parameters of thermal decomposition were determined (Ea = 102 kJ/mol, A = 9·106). The crystal structures of both compounds were refined from the X-ray powder diffraction data. Sulfate hydrate NaSm(SO4)2·H2O crystallizes in the trigonal symmetry, space group P3121 (a = 6.91820(3) and c = 12.8100(1) A, V = 530.963(7) A3). The anhydrous salt crystallizes in the triclinic symmetry, space group P-1 (a = 6.8816(2), b = 6.2968(2) and c = 7.0607(2) A, α = 96.035(1), β = 99.191(1) and γ = 90.986(1)°, V = 300.17(1) A3). The vibrational properties of compounds are mainly determined by the sulfate group deformations. The luminescence spectra of both sulfates are similar and are governed by the transitions of samarium ions 4G5/2 → 6HJ (J = 5/2, 7/2, 9/2 and 11/2). The anhydrous sulfate is stable up to 1100 K and undergoes an almost isotropic expansion when heated. After 1100 K, the compound decomposes into Sm2(SO4)3 and Na2SO4.

Here, we have thoroughly studied the effect of chemistry of graphene derivatives on the composition of N-species after N-doping with the help of core-level spectroscopy techniques. The modulation of the N-species by tailoring the functionalization and atomic structure of graphene derivatives prior to chemical N-doping is experimentally demonstrated for the first time. The large extent of non-terminated or phenol-functionalized graphene edges is found to facilitate the formation of pyridinic nitrogen with its relative content exceeding 72%. In turn, the predominant decoration by the pyrazolic moieties is shown for the perforated and carboxyl-derived graphene layers. The thermal annealing at moderate temperatures of ca.345 °C is shown to equally readjust the composition of N-species in graphene derivatives regardless of their chemistry, nanostructure, and the initial distribution of the N-species. Further examination of N K-edge X-ray absorption spectra (XAS) pointed out that the oxidation of the graphene layer governs the manifestation of the π∗ resonances and configuration of the σ∗ resonance. As a result, a set of facile methods to synthesize graphene derivatives with the desired type of the embedded nitrogen species for the optoelectronic and catalytic applications are proposed and crucial features of their identification using core-level spectroscopy techniques are emphasized.

In modern large aperture optical systems for tracking astronomical objects, the technology of bistatic schemes is widely introduced, in which the laser, the main and auxiliary telescopes are spatially separated. This requires additional measures to be taken when aligning the optical axes of telescopes, especially when tracking LEO space objects. The choice of bistatic schemes in astronomical telescopes is due to the problem of “tilt uncertainty” inherent in monostatic schemes for the formation of a laser reference star. This problem is caused by the difficulty or even the impossibility of determining the tilt of the wavefront when the laser guide star jitters in the image plane. The article discusses a monostatic scheme for constructing ground-based adaptive optoelectronic systems. The monostatic scheme combines the optical axis of the laser, which forms the laser guiding star, and the optical axis of the telescope, which serves to obtain images of space objects by eliminating phase disturbances of the atmosphere due to the radiation of the laser guiding star. The proposed method for determining the tilt of the wavefront in a monostatic scheme is based on the analysis of expressions for the dispersion of the tilt jitter of the images of a laser reference star and a space object for the case when the diameter of the receiving aperture of the telescope is much larger than the diameter of the aperture of the laser forming the laser reference star. This approach is based on the long-elicited strong correlation between the instantaneous values of the tilt of the laser beam and the received beam from a natural star, transmitted towards each other. When observing low-orbit small-sized space objects and laser reference stars, it is assumed that they are in the Fresnel zone of the receiving aperture of the optoelectronic system and within the isoplanatism angle of the atmosphere, determined within the framework of an isotropic and locally homogeneous model of atmospheric turbulence. The proposed solution made it possible to determine the value of the instantaneous tilt angle for the image of an inconspicuous space object in the focal plane of the receiving aperture of the telescope on the basis of measuring the instantaneous tilt angle for the actually observed image of the laser reference star. The results can be used in the development of ground-based adaptive optoelectronic tracking systems for low-orbit small-sized space objects.

Back-contact modification using a 10-nm ZnS layer in CZTSSe-based solar cell can play a crucial role in improving photovoltaic conversion efficiency. An ultrathin layer of ZnS is deposited over Mo-coated soda lime glass substrate before depositing CZTSSe using sputtering. The crystal structure of deposited CZTSSe thin films over ZnS is recognized as (112)-oriented, polycrystalline in nature, and free from the presence of any secondary phases such as Cu2(S,Se) or Zn(S,Se). The bandgap of CZTSSe thin films deposited over ultrathin ZnS is observed to increase from 1.49 (deposited over Mo directly) to 1.58 eV at room temperature, as determined by spectroscopic ellipsometry. In addition, numerical simulation has been performed using SCAPS software. The impact of ZnS layer has been simulated by using the defects in the absorber and at the interface of ZnS/CZTSSe. The simulated results have been validated with experimentally fabricated CZTSSe device. Simulated device with ZnS intermediate layer is observed to give rise to a photovoltaic conversion efficiency of 15.2%.

Generation of coherent radiation in the IR and terahertz ranges during the propagation of a multi-terawatt laser pulse along a nanowire target is investigated. In the process of interaction, dense electron bunches are displaced from the target and accelerated in the laser field, generating intense electromagnetic radiation. Three regimes of interaction can be realised depending on the duration and shape of the laser pulse. In the first regime, when the laser pulse is long enough (tens and hundreds of femtoseconds), electrons are only partially forced out of the target. The characteristics of the low-frequency part of the spectrum of the generated radiation are determined in this case by the duration of the laser pulse, as well as by its amplitude and target parameters (geometric dimensions and concentration of electrons). In the second regime, the laser pulse has a large amplitude and a steep rising edge (the amplitude of the first half-wave is of the order of the maximum pulse amplitude); as a result, most of the electrons are displaced from the target already at the initial moment of interaction. In this regime, unipolar and bipolar pulses with a duration of tens of laser field periods can be formed. Changing the target length makes it possible to control the period of field oscillations and their number in the generated radiation. In the intermediate regime of short laser pulses with an insufficiently steep rising edge, oscillations of the formed electron bunches can occur in the macroscopic Coulomb attraction field of the charged target, which gives rise to radiation with a frequency several times lower than that of laser radiation. In this case, the pulses of the generated radiation contain a few cycles of the field with decreasing amplitude and increasing frequency. Using numerical simulation in three regimes of interaction, the characteristics of IR and terahertz radiation are found, in particular, the pulse shapes, ranges of generated frequencies, amplitudes and angular distributions of radiation are determined. It is shown that the amplitude of the generated pulse can reach subrelativistic and relativistic values (the field strength is more than 1 TV m−1 at a frequency ten times lower than the laser radiation frequency), and the energy conversion efficiency can be of the order of one percent.

Chinese President Xi Jinping, at a meeting with delegates of the People's Liberation Army of China (PLA) during the last session of the National People's Congress (NPC), demanded the introduction of scientific discoveries and innovative technologies in the army. Xi Jinping noted that new technologies are the key to modernizing the Armed Forces. The Chinese leader discussed with the military how to achieve the goals set in the field of national defense and army development and the implementation of the 13th five-year plan for the development of the armed forces. It is safe to say that Laser Weapons (LW) are on the agenda of China/1/

Here, the synthesis of holey carbonylated (C-ny) graphene derivative and its application for gas sensing is demonstrated. The carbonylation of graphene oxide leads to the 3-fold increase in the concentration of carbonyl groups’ up to 9 at.% with a substantial elimination of other oxygen functionalities. Such a chemical modification is accompanied by the perforation of the graphene layer with the appearance of matrices of nanoscale holes, leading to corrugation of the layer and its sectioning into localized domains of the π-conjugated network. Combined with the predominant presence of carbonyls, granting the specificity in gas molecules adsorption, these features result in the enhanced gas sensing properties of C-ny graphene at room temperature with a selective response to NH3. Opposite chemiresistive response towards ammonia when compared to other analytes, such as ethanol, acetone, CO2, is demonstrated for the C-ny graphene layer both in humid and dry air background. Moreover, a selective discrimination of all of the studied analytes is further approached by employing a vector signal generated by C-ny multielectrode chip. Comparing the experimental results with the calculations performed in framework of density functional theory, we clarify the effect of partial charge transfer caused by water and ammonia adsorption on the chemiresistive response.

Subject of study. The authors propose an integrated approach to the problem of determining the aperture diameter of a probe laser that forms a laser reference star used in ground-based adaptive optoelectronic systems. The relevance of this study is due to the fact that modern large-aperture optical systems for tracking natural stars and artificial objects (spacecraft or fragments of space debris) widely implement the technology of forming laser stars and use them as reference sources for correcting phase distortions of a turbulent atmosphere. The choice of the energy and spatiotemporal characteristics of laser guide stars is related both to the parameters of the probe laser (radiation power and aperture diameter), which forms the guide star, and to the spatiotemporal characteristics of the atmosphere. Method. The diameter of the probe laser aperture (for the near and far radiation zones) is estimated taking into account the spatial coherence radius of the atmosphere r0, the radiation intensity and angular divergence of the laser beam, its random root-mean-square angular deviation (jitter) with respect to the calculated direction to the space objects. Main results. The estimation of the angular divergence of a laser beam is based on a comparative analysis and generalization of theoretical results obtained by calculating the optical resolution in systems for acquiring images of natural space objects. It is shown, in particular, that when determining the size of the aperture along with the value of the angular divergence of the probe beam, it is necessary to take into consideration the decrease in its radiation intensity with an increase in the diameter with respect to the radius of atmosphere coherence. The practical significance. The results are essential, firstly, for the development of ground-based adaptive optoelectronic systems for tracking artificial space objects, and secondly, for determining the geographic locations of the optoelectronic systems taking into account the astronomical climate.

Characteristics of a reference optical frequency spectrum formed in a circuit with a continuous laser and an amplitude modulator with a high modulation index are investigated via numerical modeling. The possibility of forming microwave oscillations of a desired frequency is demonstrated, and the generation of a broadband microwave oscillation at the modulation of two or more lines selected from the optical frequency spectrum is studied.

This article presents a theoretical analysis of high-field terahertz (THz) radiation generation from chirped laser pulse interaction with a plasma of slanting density modulation. The mechanism is based on strong nonlinear transverse current produced by the beating of two chirped laser pulses, where the plasma density modulation is inclined at angle to the propagation of the lasers. We claim that oblique spatial density ripple plays a crucial role in field enhancement of THz. At resonance (due to the phase-matching), the field strength of THz becomes maximum for a particular slating angle of the plasma density modulation. We claim that the oblique spatial density ripple and laser frequency-chirp combinedly play a crucial role in field enhancement of THz field. We observe that stable THz is generated with a maximum field strength of 100 MV/cm and a relatively broad spectrum extending out to 2.4 THz, with a strong dependence on the selection of slating angle of plasma density ripple and laser frequency chirp parameter, which corresponds to the conversion efficiency in order of 10−2. The efficiency of the process may be optimized and controlled by the laser and plasma parameters, which may be useful in various applications of these kind of high-field THz.

In the beginning of 1973 in the USSR the study of possibility of LJE designing was conducted. The reflector, located in the tail of the rocket prototype, concentrated the obtained radiation in air and ensured micro-burst that the reactive thrust was created. The successful results of different models of the reflectors tests, which were at the same time the laser light receivers, had been obtained. One should note that all experiments pointed out above were conducted with the use of electric discharge CO2- lasers with power up to 10 kW, while for the injection into orbit of different highly and technologically effective equipment (global network connections, Internet, photo-monitoring of Earth surface, debris cleaning) the radiated power substantially higher is required. Thus, for example, for SC launching with the weight 1000 kg the laser with power not less than 15 MW is necessary[1,2].

As the debate over historical antecedents to contemporary forms of lex mercatoria suggests, the nature of legal authority appears to be changing into a less familiar, more pluralistic form, even as states struggle to reassert their power. In seeking to understand this transformation in—and decentering of—the modern state's authority, we consider the multiple sources of legal authority claimed by the East India Company (1600–1757) and the way in which it positioned its legal and political legitimacy in relation to multiple and often competing centers of power in India. This article proposes the notion that the hegemony of a centralized modern state belongs only to a narrow sliver of history, hiding a much deeper pluralism within global history. In so doing, this article sets the stage for a sustained consideration of the plural nature of authority in the waxing and waning phases of the modern state.

Operation features of actuators based on the domestic electroactive polymer MF-4SK in combination with graphene electrodes is first studied. This system demonstrates several advantages, e.g. better mutual adhesion of materials, over those employing conventional flexible metal electrodes and Nafion membranes. The reported model of electroactive polymers connects sizes and structure of water-filled pores to geometrical characteristics of polymers with the goal of comparing properties of MF-4SK and Nafion polymers.

This article presents a comparison of laser sintering of deposited nanoparticles obtained by two methods of aerosol jet printing. The first printing method was based on the use of silver nanoparticles in the form of microdroplets contained in nanoink. In the second method, dry nanoparticles were obtained as a result of gas-discharge synthesis without the use of solvents. The nanoparticles in both experiments were deposited on a glass substrate in the form of a line with a width of about 50 ± 5 μm and a height of about 1.0 ± 0.2 μm. Then, the obtained lines were sintered using laser radiation with a wavelength of 1064 nm. As a result of experiments on the deposition and sintering, it was found that the electrical resistivity of the lines of sintered nanoparticles in the form of nanoink and dry nanoparticles obtained in a gas discharge was 8.1 and 4.9 μΩ·cm, respectively. Thus, it has been demonstrated that laser sintering of nanoparticles obtained in a gas discharge makes it possible to achieve a lower specific resistance of lines than the method of aerosol printing using nanoink. In addition, the electrical resistivity of the lines of sintered nanoparticles obtained in a gas discharge is 3 times greater than the electrical resistivity of bulk silver, which is a sufficient result for the creation of conductive elements of printed electronics.

The development of information technologies, changes in the nature of work, transformation of public values lead to a spread of gamification technology and its wide use in the sphere of social management of public and business structures. The authors examine the historical aspect of the development of gamification technology and its practical application in different public sectors. Generalization of the existing data on the essence of gamification made it possible to work out its concept. The authors describe the mechanism of creating a game model and analyze approaches to its design. They are convinced that the advantages of gamification as a social technology are based on specific traits of human psychology and enable its use as a mechanism of covert manipulation. The paper presents examples of using gamification in business, state regulation, management of social processes. The research of the activities of transnational terrorist organizations became a basis for the conclusion that gamification technologies are actively used for terrorist and extremist purposes. The authors also analyze the threats of using gamification in terrorist activities, specifically, for increasing interest in such actions, recruiting new members of terrorist organizations, intensifying the activity of supporters, fundraising and committing terrorist acts. Specific attention is paid to threats of using the gamification technology on the territory of the Russian Federation. The counteraction to the use of gamification technology for terrorist and extremist goals becomes a context for analyzing the normative legal acts of the Russian Federation, including the Complex Plan of Counteracting the Ideology of Terrorism in the Russian Federation in 2019-2023. The authors present a complex of measures aimed at counteracting the use of gamification technology for terrorist and extremist purposes.

The goal of this paper is to show how criminology can align its development prospects as a theory of crime prevention and counteraction with the fate of the country, with its near and distant future. In order to achieve this, it is necessary to work out, on the one hand, a correct definition of its object, theoretical and practical methodology and, on the other hand, the subject field of competencies acceptable for the society and the state. The future of criminology lies not only in meeting the challenges of today and tomorrow, but also in implementing new prospective directions for its development, in a better definition and description of some expectations, in predicting the achievement of possibly not final, but at least distant results when working out its theoretical and practical clauses and in developing «Criminology» as a theory of preventing and counteracting crimes, because its scope will be understood to be much wider and deeper than in the classical version still dominant today. It is necessary to increase professional attention as the forms and scale of crimes have changed greatly recently, and they do not in fact fit the traditional criminal law sphere because they develop according to their own logic and, in many aspects, beyond the competencies of contemporary criminology. It is claimed that in the last decades the spheres of influence for criminals have increased because of the political, environmental and banking lawlessness all over the world, including in our country, as it has coalesced with the authorities and occupied everything that it deemed to be interesting and useful and, thus, outlined a new rather wide subject field for criminology. In this connection, it is necessary to develop a criminology of the future. It includes not only the development of the theory of criminology proper, but, primarily, the implementation of the lifestyle principles, of building and providing for a life based on lawful behavior through the development of individual, public and universal, cosmically sanctified, consciousness. This approach to determining the future of criminology is considered by the author to be more adequate and dignified in the existing circumstances than «crawling away» into the essentially criminal «professional doghouse» disguised as a new doctrine of criminology.

Here, we study quasi-two-dimensional crystals of Co3O4 grown by electrochemical synthesis on Pt electrodes with a nanoflake morphology to serve as a gas sensor. When synthesizing in aqueous electrolytes under applied electrical bias, the material follows a self-hierarchical architecture to primarily appear as the hexagonal nanoflakes α-Co(OH)2. After heating up to 300 °C in air, the as-synthesized material transforms to Co3O4, preserving the original hierarchical morphology. The Co3O4 nanoflakes have been found to have remarkable chemiresistive response when exposed to various kinds of alcohol vapors, at low ppm concentrations in a mixture with air, over a wide range of temperatures up to 300 °C with a detection limit down to the ppb range with direct dependence on the molecule weight of the alcohol. We explain the observed features of the gas response of the Co3O4 nanoflakes by a shift in the electron density under the chemisorption of VOCs, verified by DFT calculations.

A method for reducing the on-state resistance of a high-power 4H-SiC metal-oxide-semiconductor field-effect transistor (MOSFET) by forming a buried channel via the growth of epitaxial layers on the surface of the heavily doped p-region is proposed. The features of the carrier transport in the epitaxial buried channel are considered in comparison with that fabricated by conventional technology. A more than threefold decrease in the resistance of the high-power MOSFET is achieved.

The dynamic characteristics of a low-voltage thyristor based on an AlGaAs/GaAs heterostructure have been studied in the mode of generation of high-amplitude pulses with width of tens of nanoseconds in a circuit with low-impedance load based on an array of high-power AlGaAs/GaAs semiconductor lasers. The presented approach uses thyristors and diode laser arrays as discrete components, so it can be extended to other (not AlGaAs/GaAs-based) semiconductor lasers. It is demonstrated that a current pulse can be generated with an amplitude of 69 A and a width of 40 ns in a vertically assembled stack of an array of semiconductor lasers and thyristors. It was shown that raising the number of single thyristors does not lead to pulse broadening and makes it possible to raise several-fold the peak current amplitude to 208 A, with the peak laser emission power reaching a value of 78 W.

A high peak and high average power femtosecond laser system based on media doped with Yb3+ ions is being developed at the Institute of Laser Physics of the SB RAS. For efficient laser amplification and to avoid optical damage is actually to compensate wave front distortion caused by grating astigmatism in pump channel. Based on theory of propagation of gaussian beam in space and through optical elements the calculation of optimal parameters of two lenses telescope and comparison with experimental data has been performed. The obtained results can be used for decrease of astigmatic effect on beam profile quality in design of laser systems with elements involving astigmatism.

Finality of judgments is a concept that puts an end to the trial, prohibiting subsequent appeals, opening of new proceedings and disputing clearly established facts. Despite being promoted by the Council of Europe and its Court of Human Rights and familiar to most if not all states, its application still encounters misunderstanding in some Eastern European Countries. Deeply rooted ideas of substantive truth and public role of the judiciary, a rather idiosyncratic notion of fair trial and the rule of law all lead to underestimation of the role played by finality in a peaceful life of the society. This article addresses the experience of Ukraine (where a major judicial reform has just taken place) and Lithuania – two post-Soviet nations that both, still in their unique way, worked on implementing the principle of finality into their procedural order. The paper also explores an uneasy balance to be found between this notion and other relevant considerations (access to justice, rule of law, judicial economy and some other).

The chemical oxidation of the cluster CpReFePt(μ3-C=CHPh)(CO)5(dppe) (Cp = η5-C5H5, dppe = η2- Ph2P(CH2)2PPh2) resulted in a radical cation [CpReFePt(μ3-C=CHPh)(CO)5(dppe)]+• that is sufficiently stable only at low temperature. An electronic structure of the radical cation was studied by EPR and following parameters were obtained by comparison of the experimental and model spectrum: gx = 2.070 gy = 2.0295 gz = 1.997; Ax(31P) = 17 Ay(31P) = 49 Az(31P) = 35 (Gs);Ax(195Pt) = 62 Ay(195Pt) = 45 Az(195Pt) = 105 (Gs). An unpaired electron is seen to be mainly concentrated on the iron atom (85-90%) and partially on the platinum atom (10-15%). Further transformation of the radical cation led to the formation of the binuclear complex Cp(CO)2RePt(μ-C=CHPh)(dppe) and the Fe-carbonyl fragment

An accurate mathematical description of the processes occurring in a scintillation spectrometer with several photodetectors registering primary particles allows obtaining correct formulas for the mean value and amplitude dispersion at the output of the photodetectors, as well as an expression for the covariance between photodetector signals. In contrast to the formulas available in the literature, the formula obtained in this work for the energy resolution of a scintillation spectrometer with one photodetector contains information on the relation between the corresponding processes occurring in the detector upon the registration of particles with the characteristics of the scintillation crystal and the scintillator-photodetector interface and the characteristics of the photodetector and the electronics of the spectrometer. It is shown that the fluctuations of the light output and the Fano factor for the scintillation crystal material can be determined using the relative covariance between photodetector signals.

The mathematical model and the results of computer simulation of the processes of compression, heating, and energy release in a target under the hybrid influence of a system of pulsed plasma jets and intense laser radiation in magnetic inertial thermonuclear fusion are presented. The hybrid effects of intense energy flows on a single-layer cylindrical target are compared in the experimental and simulation conditions. The main radiation magnetic and gas dynamic parameters of the compressed and heated target plasma are evaluated as well.

Flexible polymer-based actuators, often also called artificial muscles, are an essential part of biomimetic systems that mimic the movement principles of animal world creatures. The most used electrode material to force the actuator move is an ensemble of noble metal nanoparticles in the electroactive polymer surface. Noble metal electrodes have enough electrical conductivity and elasticity and are not subjected to oxidation. However, high cost of such electrodes and their tendency to cracking dictate the need for searching other materials, primarily carbon ones. The review considers several options for this search. For example, carbon nanotubes and graphene have excellent properties at the level of a single individually taken nanotube or graphene sheet. However, conservation of these properties in structurally imperfect film electrodes requires a separate study. In addition, there are problems of compatibility of such electrodes with the polymers that requires cumbersome technologies, e.g., hot pressing, which complicates the production of the actuator as a whole. The review concerns the technology options of manufacturing actuators and the results obtained on their basis, both including hot pressing and avoiding this procedure. In particular, the required level of the graphene oxide reduction in hydrazine provides sufficient adhesion at rather high electrical conductivity of the graphene film. The ability to simultaneous achieving these properties is a nontrivial result, providing the same level of actuation as with expensive noble metal electrodes. Actuators that additionally require greater lifetime resource should be obtained in other ways. Among them are using the graphdiyne electrodes and laser processing of the graphene electrodes.

The recent explosive growth in the number of smart technologies relying on data collected from sensors and processed with machine learning classifiers made the training data imbalance problem more visible than ever before. Class-imbalanced sets used to train models of various events of interest are among the main reasons for a smart technology to work incorrectly or even to completely fail. This paper presents an attempt to resolve the imbalance problem in sensor sequential (time-series) data through training data augmentation. An Unrolled Generative Adversarial Networks (Unrolled GAN)-powered framework is developed and successfully used to balance the training data of smartphone accelerometer and gyroscope sensors in different contexts of road surface monitoring. Experiments with other sensor data from an open data collection are also conducted. It is demonstrated that the proposed approach allows for improving the classification performance in the case of heavily imbalanced data (the F1 score increased from 0.69 to 0.72, p<0.01, in the presented case study). However, the effect is negligible in the case of slightly imbalanced or inadequate training sets. The latter determines the limitations of this study that would be resolved in future work aimed at incorporating mechanisms for assessing the training data quality into the proposed framework and improving its computational efficiency.

This study investigates the processes of interaction of nanosecond pulsed-periodic laser radiation with the flow of aerosol agglomerates of gold nanoparticles synthesized in a spark discharge. Nanoparticles in a gas flow are spatially separated nano-objects whose interaction with each other and with the walls of an experimental cell was insignificant. Therefore, the energy absorbed by nanoparticles was used only for their own heating with further shape and size modification and on heat transfer to the surrounding gas. In the research, we used laser radiation with wavelengths of 527 and 1053 nm at pulse energies up to 900 µJ and pulse repetition rates up to 500 Hz. The dynamics of changes in the nanoparticles size during their sintering process depending on the laser pulses energy is characterized by an S-shaped shrinkage curve. Complete sintering of the initial agglomerates with their transformation into spherical nanoparticles is achieved by a series of impacting laser pulses. The result of nanoparticles’ laser modification is largely determined by the pulse energy and the efficiency of the nanoparticles’ radiation absorption.

The interaction of an aqueous suspension of fine-grained iron with one equivalent of (1-hydroxy-ethylidene)diphosphonic acid (H4L) leads to the formation of poorly soluble iron(II) (1-hydroxy-ethylidene)diphosphonate (FeH2L · H2O), which precipitates from the solution in the form of whiskers. A compound consisting of crystalline and X-ray amorphous fractions, whose structure is based on stacked sheets of whiskers, linked by amorphous phase, was selected from the FeH2L · H2O reaction mixture with morpholine. The compounds have been studied by methods of elemental analysis, scanning electron microscopy, optical microscopy, atomic force microscopy (AFM), and X-ray diffraction (XRD) analysis.

Using the Richards–Wolf formula, we investigate the tight focusing of a cylindrical vector beam of second order using a high-numerical aperture lens confined by a ring aperture. It is shown that the area of energy backflow can be enlarged by the ring aperture, and that focusing light using a lens with a numerical aperture of 0.95 and a ring aperture, which limits the angle of the entrance pupil to 0.9 of the maximum value, allows us to increase the depth of the area of negative values of the Poynting vector projection onto the optical axis by a factor of four, with a slightly varying width of the region (this varies from 0.357 to 0.352 of the wavelength of the focused light). The ratio of the absolute values of the Poynting vector for reverse and direct flows is increased by a factor of 2.5.

This paper discusses the detection and measurement of small UAV radar reconnaissance. Analyzed modern directions of improvement of MTI systems. Based on the method of compensation proposed deterministic sdts providing suppression of passive noise in the area of rejectio on the principle of close to compensation point in space jamming (ACP) autocompensation direct treatment of the correlation matrix of the interference

A new method is suggested for generating quasi-unipolar electromagnetic IR and terahertz pulses. The method is based on synchronous acceleration of electrons combined to a dense bunch with a charge of up to several tens nanocoulombs, which are forced out from a nanoscale target under an action of a high-power, sharp-leading edge laser pulse. The electromagnetic bunch moving in a field of laser radiation can generate high-power electromagnetic pulses with various spectral composition including terahertz and IR ranges. A physical mechanism underlying the formation of generated quasi-unipolar pulses of electromagnetic radiation is determined and numerically studied. The pulse characteristics are found by numerical simulation, such as amplitude and duration dependences on the angle between the pulse propagation direction and laser beam axis. It is established that in modern laser installations, the amplitudes of quasi-unipolar pulses may reach relativistic values. Reflection of a unipolar pulse from an ideally reflecting surface is numerically analysed. It is shown that the pulse retains its unipolar profile in this case.

Does Prado and Hoffman's concept of an international institutional bypass have explanatory force when applied to transnational non-state regulation? Drawing on three cases studies (Accord on Fire a...

This paper reports on the results of studies of the carbonate–fluoride isolations with extremely high Y and REE concentrations from biotite–arfvedsonite granite of the Katugin rare metal deposit. We obtained the chemical data on that minerals that compose these isolations—gagarinite-(Y), tveitite-(Y), fluocerite-(Ce), bastnaesite, and fluornatropyrochlore. A carbonate–fluoride globule with a well-preserved crystallization order was revealed in quartz of the host granite. This finding might be evidence of silicate–fluorine immiscibility suggested before for the Y–REE isolations in the Katugin granites. We assumed that the fluoride melt occurred at the magmatic stage of the formation of biotite–arfvedsonite granite, which resulted in depletion of the host granite with fluorine and the redistribution of the REE and Y in the fluoride salt melt.

The main characteristics of the astroclimate (the structure of turbulent fields and conditions for their formation) are studied for several Russian astronomical observatories in southern Siberia and North Caucasus, including Sayan Solar, Baikal Astrophysical, Special Astrophysical, and Kolyvansky Ridge Observatories and the Center for Laser Atmosphere Sensing of Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences. The experimental results have been received from long-term astroclimate observations (expeditions in 2006–2017) with the use of small-size ultrasonic weather stations; and theoretical results, from the numerical solution of different boundary problems for the Navier–Stokes equations. The presence of regions with coherent (non-Kolmogorov) turbulence over the observatories has been ascertained, the formation of which is caused by the topography and the nonuniform heating of the underlying surface. Large-scale coherent vortex structures and coherent turbulence have been detected inside dome rooms. Numerical simulation allows us to analyze the influence of design features and temperature regimes of the telescope components and to test the telescope optical characteristics, including the minimization of the effects of external and under-dome turbulence. The paper includes the review of the history and evolution of the “coherent structure” and “coherent turbulence” concepts based on the world scientific literature and our own researches.

In the present study, the structure, microrelief and optical properties of the iron films deposited onto silica and silicon substrates by thermal evaporation have been evaluated. The film top surface layer is a textured iron polycrystal, as it has been verified by RHEED. When iron is deposited onto silicon, the microrelief magnitude is below 12–15 nm, as measured by AFM. The dispersive optical constants n(λ) and k(λ) of the iron films have been defined over the spectral range of λ = 250–1100 nm by spectroscopic ellipsometry. The n(λ) and k(λ) parameters open a possibility of precise thin semi-transparent iron film thickness measurement by laser ellipsometry.

Free-radical-scavenging capacity antioxidant and membrane-protective properties of natural and related synthetic allylpolyalkoxybenzenes with different numbers of alkoxy/methoxy groups in the aromatic ring were evaluated using several in vitro models. These included the DPPH assay, inhibition of lipid peroxidation products accumulation, inhibition of H2O2-induced hemolysis, and oxidation of oxyhemoglobin. A synthetic protocol for the synthesis of natural nothoapiol (9) from a parsley seed metabolite, apiol (7), was developed. A structure-activity relationship study revealed that both the methylenedioxy fragment and methoxy groups in the aromatic ring are favorable for antioxidant activity. Hydroxyapiol (14), containing a hydroxy group in the aromatic core, was identified as the most potent compound. The pentaalkoxy-substituted nothoapiol (9) showed antioxidant activity in mouse brain homogenates, whereas in mouse erythrocytes it exhibited a marked pro-oxidant effect. Despite their low free-radical-scavenging capacity, allylpolyalkoxybenzenes can contribute to the total antioxidant potencies of plant essential oils.

The peculiarities of spin-polarized electronic structure of multilayer graphene nanofilm (4-GNL:H) within the framework of Kohn --- Sham approximation were studied in the present work. The calculated band structure and spin-resolved electronic energy spectrum of the 4-GNL:H system were correlated with experimental UPS and XANES spectra of thin hydrogenated a-C:H films. As the band structure calculations show there is a dimensional quantization of energy spectrum in the 4-GNL:H system, and the energy gap of 0.11 eV appears in the spectrum. The self-consistent calculations also predict the existence of itinerant magnetism in the system, conditioned by hydrogen chemisorption.

It is shown that the features of the development of the self-initiated volume discharge in gas mixtures of a non-chain electrochemical HF laser are caused by self-organizing processes of dissipative structures representing plasma diffusion channels. The formation features of diffusion channels in the gas-discharge plasma of the self-initiated volume discharge are determined.

Strong orthogonality between differential ion mobility spectrometry (FAIMS) and mass spectrometry (MS) makes their hybrid a powerful approach to separate isomers and isobars. Harnessing that power depends on high resolution in both dimensions. The ultimate mass resolution and accuracy are delivered by Fourier Transform MS increasingly realized in Orbitrap MS, whereas FAIMS resolution is generally maximized by buffers rich in He or H2 that elevate ion mobility and lead to prominent non-Blanc effects. However, turbomolecular pumps have lower efficiency for light gas molecules and their flow from the FAIMS stage complicates maintaining the ultrahigh vacuum (UHV) needed for Orbitrap operation. Here we address this challenge via two hardware modifications: (i) a differential pumping step between FAIMS and MS stages and (ii) reconfiguration of vacuum lines to isolate pumping of the high vacuum (HV) region. Either greatly ameliorates the pressure increases upon He or H2 aspiration. This development enables free optimization of FAIMS carrier gas without concerns about MS performance, maximizing the utility and flexibility of FAIMS/MS platforms.

Objective: Efforts to achieve balance between effective pain management and opioid-related adverse events (ORAEs) have led to multimodal analgesia regimens. This study compared opioids delivered via patient-controlled analgesia (PCA) plus liposomal bupivacaine, a long-acting local anesthetic with potential to be an effective component of such regimens, to opioids delivered through PCA alone or PCA plus subcutaneous bupivacaine infusion (ONQ), following laparotomy. Design: Prospective, randomized controlled trial. Setting: Single, tertiary-care institution. Patients: One hundred patients undergoing nonemergent laparotomy. Interventions: Patients were randomly assigned to one of three study treatments: PCA only (PCAO), PCA with ONQ, or PCA with injectable liposomal bupivacaine suspension (EXP). Main Outcome Measures: Cumulative opioid use, daily mean patient-reported pain scores, and ORAEs through 72 hours postoperatively. Results: On average, the EXP (n = 31) group exhibited less than 50 percent of the total opioid consumption of the PCAO (n = 36) group, and less than 60 percent of that for the ONQ (n = 33) group. Postoperative days 1 and 3 pain scores were significantly lower for the EXP group as compared to the ONQ and PCAO groups (p ≤ 0.005). Fewer patients in the EXP group (19.4 percent) experienced ORAEs compared to the PCAO (41.1 percent) and ONQ (45.5 percent) groups (p = 0.002). Conclusions: Laparotomy patients treated with liposomal bupivacaine as part of a multimodal regimen consumed less opioids, had lower pain scores, and had fewer ORAEs. The role of liposomal bupivacaine in the postoperative care of laparotomy patients merits further study.

A method of visualization of the process of optical damage of a ZnGeP 2 single crystal using digital holography is suggested. The mechanism of the ZnGeP 2 single crystal damage is investigated at energy density ~0.3–0.6 J/cm ² . The temperature in the damage channel during its formation is estimated. The data obtained allow the conclusion on the thermal nature of ZnGeP 2 crystal damage to be made under the action of laser radiation with a wavelength of ~2.1 μm. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.

Human serum albumin (HSA) serves as a natural depot of amyloid β peptide (Aβ). Improvement of Aβ binding to HSA should impede Alzheimer's disease (AD). We developed a method for quantitation of the interaction between monomeric Aβ40/42 and HSA using surface plasmon resonance spectroscopy. The dissociation constant of HSA complex with recombinant Aβ40/42 is 0.2–0.3 μM. Flemish variant of Aβ40 has 2.5–10-fold higher affinity to HSA. The parameters of the HSA-Aβ interaction are selectively sensitive to HSA binding of major plasma unsaturated fatty acids and Cu2+. Linoleic and arachidonic acids promote the HSA-Aβ42 interaction. The developed methodology for quantitation of HSA-Aβ interaction may serve as a tool for search of compounds favoring HSA-Aβ interaction, thereby preventing AD progression.