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Polycrystalline TbxDy1-xR0.1Fe2-zCoz (R = Nd, Pr, x = 0.2, 0.3; z = 0, 1.3) cubic Laves phase alloys with MgCu2-type structure were prepared by arc melting followed by homogenizing annealing. The crystal structure, magnetic properties, and magnetostriction have been investigated. Compounds with high values of magnetostrictive susceptibility were found in the temperature range 150-300 K. Compounds with partial substitution of cobalt for iron demonstrate a change in the sign of anisotropic magnetostriction. This work continues the search for magnetostrictive materials with inexpensive neodymium and praseodymium.

The article presents research materials on the widespread use of multifunctional biological products against fungal and bacterial pathogens on the main vegetable crops cultivated in greenhouses and on potatoes. For protected ground crops: cucumber, tomato, eggplant, protection systems have been developed that help protect plants from diseases during the entire growing season. The introduction of these systems into production makes it possible to completely reduce or minimize the use of chemical plant protection products on these crops and thereby reduce the negative impact on the environment, as well as improve the quality and safety of crop products. The article presents the main biological products that are included in the potato protection system, including Kartofin, SK and Sternifag, SP.

Experimental treatments were carried out to protect winter wheat crops from harmful objects for several seasons during 2018–2020 in Belgorod region. The article presents an economic assessment of the costs and profits from the introduction of the biological preparation Sternifag, WP, which was used against the background of 3 culture protection systems (chemical, integrated and biologized). It was found that, despite the additional costs for the introduction of Sternifag, high indicators of additional yield (from 13.6 to 28.4 c / ha) and profit (from 10846.83 to 30009.02 rubles/ha) were obtained. Calculations showed that treatment with Sternifag in the field gave a high profitability from 158 to 434%. The results obtained made it possible to evaluate the effect of the microbiological preparation Sternifag, WP as a stimulating and protective agent for winter wheat.

Dihadron azimuthal correlations containing a high transverse momentum ( ) trigger particle are sensitive to the properties of the nuclear medium created at RHIC through the strong interactions occurring between the traversing parton and the medium, i.e. jet-quenching. Previous measurements revealed a strong modification to dihadron azimuthal correlations in Au+Au collisions with respect to p+p and d+Au collisions. The modification increases with the collision centrality, suggesting a path-length or energy density dependence to the jet-quenching effect. This paper reports STAR measurements of dihadron azimuthal correlations in mid-central (20%-60%) Au+Au collisions at GeV as a function of the trigger particle's azimuthal angle relative to the event plane, . The azimuthal correlation is studied as a function of both the trigger and associated particle . The subtractions of the combinatorial background and anisotropic flow, assuming Zero Yield At Minimum (ZYAM), are described. The correlation results are first discussed with subtraction of the even harmonic (elliptic and quadrangular) flow backgrounds. The away-side correlation is strongly modified, and the modification varies with , with a double-peak structure for out-of-plane trigger particles. The near-side ridge (long range pseudo-rapidity correlation) appears to drop with increasing while the jet-like component remains approximately constant. The correlation functions are further studied with the subtraction of odd harmonic triangular flow background arising from fluctuations. It is found that the triangular flow, while responsible for the majority of the amplitudes, is not sufficient to explain the -dependence of the ridge or the away-side double-peak structure. The dropping ridge with could be attributed to a -dependent elliptic anisotropy; however, the physics mechanism of the ridge remains an open question. Even with a -dependent elliptic flow, the away-side correlation structure is robust. These results, with extensive systematic studies of the dihadron correlations as a function of , trigger and associated particle , and the pseudo-rapidity range , should provide stringent inputs to help understand the underlying physics mechanisms of jet-medium interactions in high energy nuclear collisions.

This paper presents the STATCOM model in PSIM, which compensate reactive power and current harmonics from the non-linear load. Reactive power consumption and harmonics current of non-linear load given from measurement. The model of STATCOM is a multi-level voltage inverter. Constant system voltage, power factor and harmonics currents are controlled. All modes are realized and plots are plotted.

The SPASCHARM experiment at U70 aims an exploration of a fundamental problem in modern particle physics, the role of spin in strong interactions. At present, the first physics data have been accumulated at a negative 28 GeV beam, interacting with a frozen polarized proton target. The SPASCHARM wide-aperture spectrometer can detect both charged and neutral particles in the large solid angle with 2π azimuthal coverage in the fragmentation region of beam-particles. It covers the kinematic region of non-perturbative quantum chromodynamics (QCD), where the theoretical predictions are difficult and unreliable due to the full strength quark confinement at low and medium momentum transfers. In this report, the current status of the experiment is presented. The algorithm for reconstructing charged tracks is discussed along with its results on real data and the comparison with the Monte Carlo (MC) simulations. Based on a real track reconstruction, the statistical errors for the measurements of single-spin asymmetries in inclusive charged pion production are estimated. The data analysis is in progress.

In the work we presented, based on field production experiments conducted in the Belgorod region, an economic assessment of various winter wheat protection systems is given. In particular, crop protection systems with treatment only with chemical preparations (chemical) and with the integrated use of biological and chemical preparations (integrated) were studied. The most important economic indicators have been calculated, allowing to determine the most profitable, from the point of view of financial costs, systems. As a result, we found that the highest profit was obtained with using the integrated winter wheat protection system - 4446.7 rubles / ha, the profitability of these treatments was 95%. It was also found that the introduction of an integrated system is the most preferable from the point of view of protecting the environment from pollution. When applied on crops, the pesticide load on the soil is reduced, since the amount of applied chemicals is more than halved in comparison with the chemical protection system.

In the Spring 2018, the first physics data was accumulated in the new SPASCHARM experiment at U-70 accelerator of IHEP, Protvino. The first stage of SPASCHARM’s physics programs prursues the goal of studying spin effects in the beam fragmentation region at an unpolarized negative 28 GeV beam, interacting with a frozen polarized proton target. In this resport, the feasibility of measuring the single spin asymmetry AN in the reaction: π − + p↑→K 0 S + X is evaluated by Monte-Carlo simulations. We present estimates of the detection efficiency as well as for expected event statistics. It is shown that, in the process of interest above, the attainable statistical errors for AN would be at the scale of a few percents.

High transverse momentum ( ) particle production is suppressed owing to the parton (jet) energy loss in the hot dense medium created in relativistic heavy-ion collisions. Redistribution of energy at low-to-modest has been difficult to measure, owing to large anisotropic backgrounds. We report a data-driven method for background evaluation and subtraction, exploiting the away-side pseudorapidity gaps, to measure the jetlike correlation shape in Au+Au collisions at GeV in the STAR experiment. The correlation shapes, for trigger particles and various associated particle ranges within , are consistent with Gaussians, and their widths increase with centrality. The results indicate jet broadening in the medium created in central heavy-ion collisions.

Research has been carried out on the thermal insulation properties of a new composite material based on straw and synthetic rubber of low-temperature vulcanization. The values of heat transfer resistance (Rcp) and thermal conductivity coefficient (λ) are determined depending on the humidity of the environment.

Current decays after disruptions as well as after noble gas injections in tokamaks are examined. As is shown, the cooled plasmas at the stage of current decay are partially opaque for radiation in lines giving the main impact into total thermal losses. The thermal balance is supposed to be determined by Ohmic heating and radiative losses. A zero-dimensional model for radiation losses and temperature distribution over minor radius is used. Plasma current evolution is simulated with DIMRUN and DINA codes. Impurity distribution over ionization states is calculated from the time-dependent set of differential equations. The opacity effects are found to be most important for simulation of JET disruption experiments with beryllium- and carbon-seeded plasmas. The decay times calculated are in good agreement with the experimental values. Current decays in beryllium-, carbon-, argon- and neon-seeded plasmas for ITER parameters are simulated. The temperatures after thermal quench are shown to be significantly higher in comparison with the model of transparent plasmas. Opacity effects are found to be most important for Be- and C-seeded plasmas. Runaway electron currents are damped significantly if opacity effects are taken into account in any case examined.

Plasma edge cooling during noble gas injection into a tokamak is discussed. It is shown that a noble gas jet is not able to cool the edge sufficiently for MHD activity initiation. The possibility of additional cooling by natural carbon together with hydrogen neutrals penetration from the wall is analysed.

We present first measurements of the pseudorapidity and azimuth $(\eta,\phi)$ bin-size dependence of event-wise mean transverse momentum $ $ fluctuations for Au-Au collisions at $\sqrt{s_{NN}} = 200$ GeV. We invert that dependence to obtain $p_t$ autocorrelations on differences $(\eta_\Delta,\phi_\Delta)$ interpreted to represent velocity/temperature distributions on ($\eta,\phi$). The general form of the autocorrelations suggests that the basic correlation mechanism is parton fragmentation. The autocorrelations vary strongly with collision centrality, which suggests that fragmentation is strongly modified by a dissipative medium in the more central Au-Au collisions relative to peripheral or p-p collisions. \\

Noble gas injection for disruption mitigation in DIII-D is simulated. The simulation of the first two stages of the disruption is performed: the first one is the neutral gas jet penetration through the background plasmas, and the second one is the instability growth. In order to simulate the first stage, the MHD pellet code LLP with improved radiation model for noble gas is used. Plasma cooling at this stage is provided by the energy exchange with the jet. The opacity effects in radiation losses are found to be important in the energy balance calculations. The magnetic surfaces in contact with the jet are cooled significantly; however, the temperature as well as the electric conductivity, remains high. The cooling front propagates towards the plasma centre. It has been shown that the cooling front is accompanied by strongly localized ‘shark fin-like’ perturbation in toroidal current density profile. The simplified cylindrical model shows that the cooling front is able to produce the internal kink-like mode with growth rate significantly higher than the tearing mode. The unstable kink perturbation obtained is non-resonant for any magnetic surface, both inside the plasma column, and in the vacuum space outside the separatrix. The mode disturbs mainly the core region. The growth time of the ‘shark fin-like’ mode is higher than the Alfven time by a factor of 10–100 for DIII-D parameters.

Modelling of carbon pellet injection into hot hydrogen plasma is performed. Models of ionization and radiation processes previously used for descriptions of the ablation clouds are discussed. It is demonstrated that the assumption made by other authors that the plasma is transparent significantly overestimated ionization lengths for carbon. The optical thickness of the cloud is estimated. With typical ablation rates, the cloud in the vicinity of the pellet is opaque for resonant radiation in lines, in contrast to the visual transparency for non-resonant photons. The ionization by incident electrons is not sufficient to provide the short experimental cloud sizes. A reduced model for the ion stripping dynamics and energy losses in optically thick plasmas is proposed. Two very important phenomena are taken into account: partial trapping of resonant photons in the cloud and ionization from the excited state. The model is included into the MHD pellet code LLP. Calculations with the new model show at least a qualitative agreement with the experimental sizes of the carbon clouds, in contrast to the models used earlier.

Radiative instabilities in an impurity-seeded plasma are investigated when the plasma is supposed to be highly but partially ionized. Since in such plasmas radiative losses strongly depend on neutral and impurity densities, their dynamics are taken into account. As a result, a new radiative-recombination instability is found and described. We show that the influence of the ionization-recombination balance on plasma stability is sufficient for plasma densities above 1014 cm-3. The effects of a finite impurity Larmor radius are not small and play a stabilizing role as well as the thermal forces. On the other hand, compressibility of the magnetic field leads to plasma destabilization. We note that this radiative-recombination instability accumulates impurities in a cold zone while cleaning other regions.

A new experiment SPASCHARM for systematic study of polarization phenomena in inclusive and exclusive hadronic reactions is currently under commissioning at IHEP. The universal experimental setup will detect dozens of various resonances and stable particles produced in collisions of unpolarized beams with the polarized target, and at the next stage, using polarized beams. At the first stage with polarized target, the final states composed of light quarks (u, d, s) will be reconstructed. Hyperon polarization and spin density matrix elements of the vector mesons will be measured along with the single-spin asymmetries. The 2π-acceptance in azimuth, which is extremely useful for reduction of systematic errors in measurements of spin observables, will be implemented in the experiment. The solid angle acceptance of the setup, Δθ≈250 mrad vertically and 350 mrad horizontally in the beam fragmentation region, covers a wide range of kinematic variables pT and xF. This provides the opportunity for separating dependences on these two variables which is usually not possible in the setups with a small solid angle acceptance. Unlike some previous polarization experiments, the SPASCHARM will be able to simultaneously accumulate and record data on the both, charged and neutral particle production.

A new experiment SPASCHARM devoted to a systematic study of polarization phenomena in hadron-hadron interactions in the energy range 10-70 GeV is under preparation at IHEP (Protvino). The physical observables will be single-spin asymmetries, hyperon polarizations and spin-density matrix elements. A universal setup will detect and identify various neutral and charge particles in the full azimuthal angle and a wide polar angle range. A polarized target is used to measure the SSA. The SPASCHARM sub-detectors are being designed and constructed now. The possibility of obtaining a polarized proton beam for the SPASCHARM experiment from Lambda decays is under study.

The statistics of the failure of injection lasers was investigated experimentally in the pulsed mode at 300°K and it was compared with the Weibull distribution. A satisfactory agreement was obtained for a form parameter of 2. The influence of the repetition frequency on the average service life was investigated.