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Abstract—Experiments were carried out on the production and testing of hard alloys from VK10KhOM and VRK15 powders coated with multigraphene obtained by the electrochemical method. Samples with multigraphene were sintered under standard conditions for the VK10KhOM and VRK15 grades. The amount of multigraphene additive was 0.1 wt % for the VK10KHOM alloy and 0.1 and 0.5 wt % for the VRK15 alloy. Friction tests on VK10KhOM samples showed that the width of wear areas of samples with multigraphene is 8% smaller than the original ones. At 0.1 wt % of multigraphene, the density of samples of the VK10KhOM grade is 14.5 g/cm3and VRK15 is 14.0 g/cm3, and the porosity is 0.02 and 2%, respectively. Comparative tests were carried out on cutting VT-3 titanium. As a result of cutting, it was found that the coating of powders with multigraphene increases the durability of carbide inserts of both grades. It was shown that, for VRK15, the plate life increased by 4 times, but for the VK10KhOM grade, it was not possible to determine the failure time of the plate. The increase in wear resistance is presumably caused by a decrease in the coefficient of friction due to multigraphene, which, when dissolved in the hard alloy, is released in the form of graphite.

Grid-interactive efficient buildings can provide many benefits for the power grid. However, it is very challenging to coordinate their operations intelligently due to many considerations, e.g., privacy protection and scalability. To this end, this paper investigates an optimal coordination operation problem of multiple grid-interactive residential buildings under uncertainties to minimize the total peak demand violation of all residential buildings during the grid service periods while minimizing their respective operation cost. Taking into account multi-source uncertainties, temporal and spatial couplings, inexplicit thermal dynamics models, and the lack of information sharing among residential buildings incurred by privacy protection, it is difficult to design a centralized model-based optimization operation method. To overcome the challenge, we design an online distributed coordination operation algorithm based on the alternating direction method of multipliers (ADMM) and relative entropy regularized policy iteration (RERPI). The designed algorithm consists of two stages, i.e., independent offline training of each RERPI-based agent related to the building energy management system controller (BEMSC) in each residential building (stage-1) and online distributed execution for coordination between the aggregator controller and each BEMSC under the ADMM framework (stage-2). Simulation results verify the effectiveness and scalability of the designed algorithm.

In order to improve the voltage quality of buses in active distribution networks with high photovoltaic penetration, power compensation of controllable resources is widely used. How to develop a method to reduce communication burden while facilitating their optimal coordination is rarely discussed. This article designs an optimal voltage regulation method via hybrid power compensation. First of all, an event-triggered mechanism based on multiconstraint of changes in power flow is designed, thereby dividing all instants into trigger and nontrigger types. Both voltage offset at trigger instants and voltage fluctuation at nontrigger instants are mitigated by using a hybrid coordinated power compensation. By establishing a quantitative index, the optimal tradeoff performance for hybrid power compensation is analyzed under the event-triggered way. Finally, the case study verifies the effectiveness of the proposed method.

It is a critical issue for achieving dynamic average consensus (DAC) in the presence of privacy eavesdroppers and false data injection (FDI) attacks, and this scenario is applicable to intelligent transportation systems. A dynamic event-triggered privacy preserving DAC (DET-PPDAC) control scheme is proposed. Firstly, in a privacy-sensitive scene, different time-varying terms are added to communication states by hiding real information from eavesdroppers. An observer and a compensator are designed to construct a control scheme for compensating for the impact of FDI attacks over a channel between a control signal and an actuator. Adaptive auxiliary variables are introduced for compensating for residual errors owing to asymmetric encryption/decryption functions. Dynamic event-triggered conditions are constructed to reduce the number of data as well as the risk of leakage by eavesdroppers, and continuous monitor from neighbors is removed. Our DET-PPDAC control scheme can also be applied to a directed graph. Stability analysis shows that the control scheme finally achieves DAC with bounded errors and Zeno-free behaviors while satisfying the requirement of privacy preservation. Simulation examples with formation of vehicles are given to demonstrate the effectiveness of the proposed control scheme.

Exploiting the potential for aggregation regulation of virtual power plants (VPPs) on the distribution network side to support the frequency regulation (FR) of the main grid is an essential research topic. However, in the process of implementing FR through communication networks, the imperfect communication may affect the rapid power support performance of the VPP. As such, we propose a cyber-physical collaboration based control method. In the physical layer, in order to effectively respond to power regulation instructions, a dispatch-based control strategy is presented according to the adjustment capacity of the VPP. In the cyber layer, a joint spectrum scheduling and relay power allocation method is developed to mitigate the impact of network uncertainty and meet communication demands. Finally, extensive simulation results verify the effectiveness of the proposed method.

When there is a sudden load disturbance in an islanded microgrid, the peer-to-peer control model requires the energy resource to maintain a margin of generation, resulting in a relatively limited regulation range, that is, voltage/frequency sometimes requires additional control to maintain stability. A “source–storage–load” coordinated master–slave control strategy is proposed in this study to address the aforementioned issues. The system voltage and frequency will be stable as long as the output frequency and voltage of the master resource are stable. Furthermore, it can fully utilize the power supply capacity of resources to support the supply–demand balance. The following tasks are included in the proposed strategy: 1) to improve the operational security in the face of load disruption, a source–storage–load coordinated control method based on the “ramping speed” ratio is proposed, which can quickly restore the balance of supply and demand; 2) to improve the communication reliability in the face of interruption, a channel planning method is proposed, which can address the communication interruption problem by constructing an internal network among source–storage–load; and 3) to improve the mode switching stability of resources subjected to external disturbance, the external disturbance suppression and stability analysis involved in the regulation process are completed using sliding-mode control and small signal model methods. Related case studies are carried out to verify the effectiveness of the proposed strategies.

A novel approach for simulating the process is proposed in this work, which studies the influences of shot peening parameters such as peening angle, the size of balls on the surface roughness, and residual compressive stress material. An attempt has been made to address this issue by indicating a finite element model with randomly distributed balls developed with ABAQUS python program. A Johnson–Cook material model coupling the random ball theory is implemented into the FEM model to characterize the dynamic process of shot peening and surface modification properties of materials. In the proposed approach, the shot peeing parameters including the shot size, incidence angle, and velocity are estimated by parametric modeling to determine peening coverage precisely; furthermore, the effects of shot peening parameters on the residual compressive stress (RCS) and roughness are investigated. The shot peening simulations for AISI 4340 steel are carried out to validate the random balls model. The results show that the RCS distribution and surface roughness obtained by using the proposed method are in agreement with the experimental results in references.

Abstract: The biodiversity of the soil microbiome and its stability are central to the preservation of soil fertility in agroecosystems. Intensive technologies of the cultivation of industrial orchards require the abundant application of mineral fertilizers, which have a negative impact on the soil. Currently, bio-based formulations, which adjust the soil biota activity and increase the bioavailability of mineral nutrients, including those introduced with traditional fertilizers, are becoming widespread. Modern approaches based on the use of DNA metabarcoding allow the actual impact of various agrotechnological practices on the structure of the soil microbiome to be assessed. The effect of mineral fertilizers per se or in combination with the biological preparation Baikal EM1 on the microbiome of the soil, rhizosphere, and leaves, and shoots of apple trees is studied in an intensive apple orchard. Traditional fertilizer application causes considerable changes in the soil microbiome. The additional application of Baikal EM1 means these changes are less pronounced so the structure of the soil and rhizosphere microbiome became close to that of the intact soil. A reduction in the rate of application of chemical fertilizers in combination with the Baikal EM1 biological preparation causes no decrease in the content of the key elements of mineral nutrition in the apple plants, and the increase in the yield is comparable to that observed in plots fertilized only with chemical fertilizer. The applications of DNA metabarcoding to assess the effect of biological preparations on the soil microbiome of agroecosystems are discussed.

The results of computer and physical modeling of pipe steel hot rolling on a continuous rolling mill 2000 are presented. The moment of growth of austenite grains and the reasons for their growth are determined. The possibility of grinding the microstructure of the metal before controlled cooling, and the thermal deformation conditions conducive to grinding are investigated. It is shown that Nb (C,N) are not a factor in stopping the growth of austenite grains, but only inhibit the growth processes.

This research presents an advanced method for measuring State of Charge (SoC) in Vanadium Redox Flow Batteries (VRFB) using Refractive Index (RI) combined with Machine Learning (ML). The study comprised of three primary phases: ex-situ measurements, in-operando measurements, and ML model training. Initially, tests were conducted using a hybrid photonic-microfluidic sensor on simulated solutions mimicking specific VRFB SoCs. Subsequently, in-operando measurements were performed during cyclic processes within an experimental VRFB. Finally, utilizing the experimental data, an ML model was trained to accurately predict SoC by analyzing spectral characteristics. This study illustrates the potential of RI-based VRFB SoC measurement methods over the long term and addresses technological gaps by establishing a platform for precise SoC prediction with minimal cycle data.

The objective of this research is to predict tool wear by quickly and accurately analyzing the cutting parameters range of the machinable area that the typical hard-to-machine material, 7075 ultra-high-strength aluminum alloy. Firstly, the four-factor and four-level cutting finite element simulation model is established, and the range analysis of the orthogonal experiment results is carried out. Secondly, a tool wear experimental platform is set up in order to perform gray correlation analysis on the experimental data and compare or validate the findings with the finite element simulation results. In the end, mathematics and statistics principles or the machine learning and artificial intelligence theories are used to develop the tool wear prediction model. Regression analysis and performance evaluation analysis are then conducted on the prediction model. The findings demonstrate that cutting experiments may be precisely and successfully guided by the cutting finite element simulation model. The feed per tooth has the greatest influence on tool wear, followed by cutting speed, cutting depth and cutting length. The tool wear prediction model based on mathematical and statistical principles, machine learning and artificial intelligence theories can effectively guide the tool wear prediction, and the prediction accuracy of the optimized prediction model has been greatly improved. Engineering applications for research on numerical simulation and tool wear prediction in ultra-high-strength aluminum alloy cutting are particularly valuable.

Passivation engineering has been identified as an effective strategy to eliminate the targeted interfacial defects for improving the efficiency and stability of perovskite solar cells (PSCs). Herein, 4-trifluorophenylammonium iodide (CF3PhAI) is presented as a multifunctional passivation agent to modify buried SnO2/perovskite and perovskite/hole transport layer (HTL) interfaces. Upon incorporation of CF3PhAI between SnO2and perovskite, CF3PhAI can chemically link to SnO2via Lewis coordination and electrostatic coupling, thereby effectively passivating under-coordinated Sn and filling the oxygen vacancy. Meanwhile, CF3PhAI helps anchor PbI2and organic cations (MA+/FA+) to control the crystallization of the perovskite. Consequently, reduced interfacial defects, homogeneous perovskite crystallites, and better energetic alignment can be simultaneously achieved. When CF3PhAI was further used to modify the perovskite/HTL interface, the fabricated PSCs yielded an impressive power conversion efficiency of 23.06% together with negligible J–Vhysteresis. The unencapsulated devices exhibited long-term stability in wet conditions (91.8% efficiency retention after 1000 h) due to the water-resistant CF3PhAI. We also achieved good light soaking stability, maintaining 86.1% of its initial efficiency after aging for 720 h. Overall, our finding provides a promising strategy for modifying the dual contact interfaces of PSCs toward improved efficiency and stability.

The remarkably narrow central line in the electron paramagnetic resonance spectrum and the very weak zero-field splitting (ZFS) make [GdIII(NO3Pic)] ([GdIII(TPATCN)]) an attractive starting point for the development of spin labels. For retaining the narrow line of this parent complex when modifying it with a substituent enabling bioconjugation, alkyl with a somehow remote functional group as a substituent at the picolinate moiety was found to be highly suitable because ZFS stayed weak, even if the threefold axial symmetry was broken. The ZFS is so weak that hyperfine coupling and/or g-value variations noticeably determine the linewidth in Q band and higher fields when the biomolecule is protonated, which is the standard situation, and in W band and higher fields for the protonated complex in a fully deuterated surrounding. Clearly, [NDSE-{GdIII(NO3Pic)}], a spin label targeting the cysteines in a peptide, is at a limit of linewidth narrowing through ZFS minimization. The labeling reaction is highly chemoselective and, applied to a polyproline with two cysteine units, it took no more than a minute at 7 °C and pH 7.8. Subsequent disulfide scrambling is very slow and can therefore be prevented. Double electron–electron resonance and relaxation-induced dipolar modulation enhancement applied to the spin-labeled polyproline proved the spin label useful for distance determination in peptides.

Formation control is a hot topic in multiagent systems (MASs). In this article, a bipartite time-varying prescribed range formation is developed for a class of nonlinear MASs with unknown disturbances. The time-varying prescribed range formation means that agents achieve a formation shape within a predefined region relative to their neighbors, and the region changes along with the time-varying formation distance. An error transformation is introduced to transform this bipartite prescribed range formation problem into a stabilization control one. A surface-error-based predictor is developed to generate prediction errors for update of neural networks (NNs), and this form decouples approximation of system dynamics and control signal. With prescribed range information and signed graph, a disturbance observer with predictor-based NNs is constructed to compensate external disturbances and NNs' approximation errors. Also, a normalization learning method is employed to reduce the number of NN's learning parameters. With Lyapunov-based stability analysis, it is proven that a bipartite time-varying formation is achieved within a prescribed range. Simulation results with a group of quadrotors verify the effectiveness of the proposed bipartite control scheme.

Resistant hypertension is associated with increased cardiovascular risk. The endothelin pathway has been implicated in the pathogenesis of hypertension, but it is currently not targeted therapeutically, thereby leaving this relevant pathophysiological pathway unopposed with currently available drugs. The aim of the study was to assess the blood pressure lowering efficacy of the dual endothelin antagonist aprocitentan in patients with resistant hypertension.

An elaboration of the photonic based sensors is the most promising direction in modern analytical chemistry from the point of view of real clinical applications. The highest sensitivity is demonstrated by sensors based on photonic integrated circuits (PICs). This type of sensor has been recently successfully combined with microfluidics, which decreased the analyte volume for analysis down to microliter units. The most significant disadvantage regarding these photonic sensors is low specificity. One of the methods that could be useful for such type of problem is the layer by layer (LBL) assembly. The peculiarity of a PIC based sensor is the ability to precisely control surface modification by using measurements of a minimum resonance position shift. The bovine serum albumin (BSA) and tannic acid (TA) molecules were selected for LBL assembly because on one side they form a stable LBL assembly film based on hydrogen bonds, while the other side of both TA and BSA molecules can be used for conjugation with target molecules. A microring resonator (MRR) and a Mach–Zehnder interferometer (MZI) based on a silicon nitride platform combined with a microfluidic system were elaborated and used for monitoring the LBL film assembly. Obtained results have a good correlation with measurements carried out by atom force microscopy. Thus, the ability of using PIC based sensors for in situcontrol of surface modification was demonstrated and can be considered in point-of-care (POC) devices that have a very good perspective for both early pathological state diagnosis and evaluation of treatment efficiency.

Nuclear magnetic resonance suffers from an intrinsically low sensitivity, which can be overcome by dynamic nuclear polarization (DNP). Gd(III) complexes are attractive exogenous polarizing agents for magic angle spinning (MAS) DNP due to their high chemical stability in contrast to nitroxide-based radicals. However, even the state-of-the-art Gd(III) complexes have so far provided relatively low DNP signal enhancements of ca. 36 in comparison to standard DNP biradicals, which show enhancements of over 200. Here, we report a series of new Gd(III) complexes for DNP and show that the observed DNP enhancements of the new and existing Gd(III) complexes are inversely proportional to the square of the zero-field splitting (ZFS) parameter D, which is in turn determined by the ligand-type and the local coordination environment. The experimental DNP enhancements at 9.4 T and the ZFS parameters measured with pulsed electron paramagnetic resonance (EPR) spectroscopy agree with the above model, paving the way for the development of more efficient Gd(III) polarizing agents.

This paper presents the results of a study of the search and detection of iron ore minerals in the dumps of mining enterprises by the method of georadiolocation. The possibilities and technologies of the development of a technogenic deposit with low costs for the production of iron ore are shown. The main advantage is the presence of minerals already on the surface and does not require complex mining technology. The next stage considers the issues related to the problems of the technology of preparation of the charge for the production of cast iron when using the raw materials of technogenic deposits. Special attention is paid to the content of various alloying additives, an assessment of their influence on the properties of gray cast iron is given.

The article considers the features of the technology of iron smelting in small foundries. The paper presents data on the sulfur content in the metal, various options for metal desulfurization are considered. These technologies allow us to obtain high-quality metal. The use of such cast iron will significantly improve the quality of metal products.

Alkaptonuria is characterized by the accumulation of homogentisic acid (HGA), part of which is excreted in the urine but the excess HGA forms a dark brown ochronotic pigment that deposits in the connective tissue (ochronosis), eventually leading to early-onset severe arthropathy. We analyzed a cohort of 48 Russian AKU families by sequencing all 14 exons (including flanking intronic sequences) of the homogentisate 1,2-dioxygenase gene (HGD) and Multiplex Ligation-dependent Probe Amplification (MLPA) analysis. Nine novel likely pathogenic HGDvariants were identified, which have not been reported previously in any other country. Recently, Bychkov et al. [1] reported on the variant spectrum in another cohort of 49 Russian AKU patients. Here we summarize complete data from both cohorts that include 82 Russian AKU families. Taken together, 31 different HGDvariants were found in these patients, of which 14 are novel and found only in Russia. The most common variant was c.481G>A (p.(Gly161Arg)), present in almost 54% of all AKU alleles.

Abstract: A comparative study of the effect of osteoplastic materials based on tricalcium and octacalcium phosphate on the repair of bone defects in the pineal gland of Wistar rats was carried out at follow-up periods of 30, 60, and 90 days. It was found that the material based on octacalcium phosphate demonstrates a statistically significant increase in new bone tissue and a satisfactory rate of biodegradation in comparison with xenogenic apatite and tricalcium phosphate in all groups of experimental animals.

We propose and realize a single-mode surface plasmon polariton (SPP) waveguide formed by two parallel grooves on the surface of a high-quality silver film. In the waveguide, the SPP wave undergoes the Goos–Hänchen shift of up to 0.77⋅λ_SPP at each successive reflection, with the electric field of the SPP wave outside the metal, which significantly reduces the metal loss of the guided SPP wave. Using the waveguide, we demonstrate a complex on-chip optical circuit that includes (1) SPP plane wave excitation, (2) SPP plane wave focusing with a parabolic mirror, and (3) coupling of the focused SPP wave to the waveguide.

We aim to identify possible biological, social, and economic factors that could influence the prevalence of foodborne botulism (FB). The objective of this article is to assess epidemiological peculiarities of FB in Ukraine from 1955 to 2018 using national epidemiological surveillance data. This article presents an epidemiological descriptive population-based study of the epidemiology of FB using correlation analysis. From 1955 to 2018, 8614 cases of botulism were recorded in Ukraine causing 659 deaths. The distribution of types of botulism toxins is represented by type A (7.97%), B (59.64%), suspected as C (0.56%), E (25.47%), others (5.33%), and unidentified (1.04%). From 1990 to 2015, the rate correlation between Human Development Index (HDI) and incidence of botulism was −0.75 ± 0.20. Homemade canned meat and fish continue to be the leading causes of botulism in Ukraine. Cases related to commercial food were rare or absent, but in recent years (2017–2018), their percentage has increased to 32.56%. The HDI and botulism have an inverse mathematical correlation and predictable logical relationship: with an HDI increase, the incidence of FB decreased. In general, food botulism in Ukraine is related to traditional socioeconomic factors related to cultural food habits. In the face of declining living standards and uncertainty that food products will be physically or economically available, homemade preservation increases. Home food preservation is a major cause of botulism in Ukraine. The elimination of FB is possible in Ukraine only with the complete cessation of home canning and state control over the manufacture and sale of commercial canned products.

Decasubstituted pillar[5]arenes containing amidopyridine fragments have been synthesized for the first time. As was shown by UV–vis spectroscopy, the pillar[5]arenes with p-amidopyridine fragments form supramolecular associates with Cu(II) and Pd(II) cations in methanol in a 2:1 ratio. Using a sol–gel approach these associates are transformed into metallo-supramolecular coordination polymers (supramolecular gels) which were characterized as amorphous powders by scanning electron microscopy (SEM) and dynamic light scattering (DLS). The powders are able to selectively adsorb up to 46% of nitrophenols from water and were incorporated into an electrochemical sensor to selectively recognize them in aqueous acidic solution.

Abstract: The article addresses problems of the periphery and peripheralization of Russia’s spatial development, a significant part of which experienced negative socioeconomic development during the transition to a market economy and continues to struggle at present. Theoretical approaches of Russian and foreign authors to defining the concepts of periphery and peripheralization of space are considered. By comparative analysis and systematization, the authors have identified the six basic approaches researchers use to define the term periphery: positional, functional, problematical, generative-translational, social, and subjective. The content and features of each approach are also revealed. The authors have highlighted such basic properties of the periphery as multiform remoteness, economic degradation, social marginalization, multiscale character, migration outflow, ubiquity, relativity, and weak involvement in global economic relations. A system of indicators is proposed that characterize the periphery in accordance with the identified approaches. The spatial development of individual centers of Russia along with degradation of most of its territory significantly actualizes the question on the future of the Russian periphery and its impact on the spatial development of the country as a whole. Due to its own weak potential, the Russian periphery cannot independently attract socioeconomic development and requires strengthening of state regulation measures based on the competitive advantages of each territory.

The possibility to use the split ring resonator – SRR in a microwave filter design is investigated. SRR is made from non-ferrous metals, is one of the variants of the inclusions in the metamaterial. The periodic SRR structure modifies the permittivity and permeability of the source material, to obtain a negative refractive index. These unique properties are widely used in microwave technology, because they allow to create devices with improved performance and extended functionality. Microstrip line with etched SRR on ground plane is considered. The equivalent circuit model for SRR is shown. The paper presents calculation and comparison of the return and transmission responses for SRR structure with series coupling feed lines and with parallel coupling feed lines. The basic relationships for calculating the S-parameters (the return S11(F) and transmission responses S21(F)) are given. S-parameter calculation is made. When the reflection coefficient S11(F) reaches the maximum value, and the transmission coefficient S11(F)- the minimum, the filter operates at the resonance frequency Fp. Simulation are made using the software of Microwave Office. The results are presented in graphs. The dependence of the resonant frequency of the filter from the value of the permittivity of the substrate is found. The effect of the type of metal (copper, gold, silver), from which made the SRR on the resonance frequency of the filter is defined. It is concluded that the increase in the value of the permittivity of the substrate causes a decrease in the value of the resonant frequency of the filter. While the type of metal material of the SRR, on the resonance filter properties do not have a significant influence. The research results will reduce the time spent on the design and optimization of the design parameters.

Short-term treatment for people with type 2 diabetes using a low dose of the selective endothelin A receptor antagonist atrasentan reduces albuminuria without causing significant sodium retention. We report the long-term effects of treatment with atrasentan on major renal outcomes.