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A longitudinal relaxation time of a nitrogen-14 atom nuclear spin for a nitrogen-vacancy (NV) colour centre in diamond is measured by the modified double optical resonance method. The diamond sample was grown by the method of high temperature and pressure and comprised 1 ppm of NVcentres. The longitudinal relaxation time was 43(6) s, which was compared to the time calculated in the model of relaxation due to the electron spin of colour centre interaction with phonons and spin reservoir. The time measured well agrees with predictions of the model.

The paper considers the influence of the substrate polarity on the preparation of samples from sols for examination by X-ray photoelectron spectroscopy and atomic force microscopy.

The TAIGA experiment in Tunka valley is expanding the present scintillation detector array with new TAIGA-Muon detector stations. A simulation model was developed for optimization of the layout of the new stations and study of the identification performance of the array. The extensive air showers (EASs) were simulated with the CORSIKA simulation tool, and the detector response was simulated with the GEANT4 package. EASs induced by gamma quanta or protons in the energy range from 1 PeV to 10 PeV and the zenith angle range from 0° to 45°, are used for these studies. For the identification of high energy extensive air showers, a method based on a neural network was suggested. With this method, the proton identification efficiency is more than 90%, while the gamma identification efficiency not less than 50%.

In this paper we propose a lattice insertion for the Nuclotron ring called a “spin navigator” that can adjust any direction of the proton polarization in the orbital plane using weak solenoids. The polarization control is realized in the spin transparency mode at the energy of 108 MeV, which corresponds to the integer spin resonance γ G = 2. The requirements on the navigator solenoid fields are specified considering the criteria for stability of the spin motion during any manipulation of the polarization direction in an experiment. The paper presents the results of numerical modeling of the proton spin dynamics in the Nuclotron ring operated in the spin transparency mode. The verified spin navigator is aimed at an experimental study of a spin-flipping system using the Nuclotron ring. The results are relevant to the NICA (JINR), EIC (BNL) and COSY (FZJ) facilities where the spin transparency mode can be applied for polarization control.

This work represents the investigations for decreasing acceleration gap breakdown probability of plasma source of electrons SOLO, with grid stabilization of the boundaries of the arc cathode plasma. We increased the distance to the treated target, bent the transportation channel of the electron beam, created additional plasma in the anode space, and increased the beam front. The effect of the above measures on the breakdown probability when the target is exposed of a low-energy electron beam with a power density of up to 0.5 MW/cm2 with a diameter of 2.5 cm was investigated separately. Beam deflection is most effective at relatively long pulse durations of 150 μs and accelerating voltage of 20 kV, rather than a lower one. It was possible to double the maximum power for the same beam transport length applied to a low-melting target. Preionization in the anode proved to be effective for relatively short beams of 15 μs duration.

The effect of electron irradiation of barley seeds of the Vladimir variety on the development of plants, disease incidence and productivity in controlled greenhouse conditions has been studied. It was found that the effectiveness of the effect of seed treatment with low-energy electronic radiation in the dose range of 30–150 kGy on the morphometric parameters of barley largely depends on the accelerating voltage – 130 kV (mode 1) and 160 kV (mode 2). It was noted that irradiation suppressed the formation of chlorophyll a and b and carotenoids in barley leaves at all doses and irradiation regimes and, at the tendency level, reduced the infestation of Bipolaris sorokiniana plants in the tillering and heading phases. It was shown that irradiation of seeds caused an increase in the total tillering of plants (mode 2), but at the same time reduced the productive tillering. Electron irradiation caused an increase in the mass of 1000 grains and did not affect the yield of grain and straw.

The use of a modern element base makes it possible to create power supplies with a transition from a direct mode of generation of an auxiliary discharge to a pulse-periodic mode with a pulse repetition rate at the level of several tens of kHz. This allows for a more flexible adjustment of the discharge parameters, keeping the average value of its current, but changing its amplitude with a corresponding change in the pulse duty cycle. In this work, using an electron accelerator based on ion-electron emission, generating a wide-aperture electron beam, we research the effect of auxiliary discharge generation mode (direct and pulse-periodic) on the efficiency of electron beam extraction into the ambient atmosphere. It is shown that, in a direct mode of electron beam generation at an accelerating voltage of 150 kV, the beam extraction coefficient does not exceed 0.25. The possibility of increasing the extraction coefficient to K = 0.55 at the same accelerating voltage of 150 kV was demonstrated without making changes to the design of the accelerator, but switching to a pulsed-periodic mode of emission plasma generation.

This paper presents the results of studying the stability of the plasma emitter of an electron accelerator based on ion-electron emission during the transition from self-sustained continuous to self-sustained frequency (up to 50 kHz) repetitively pulsed generation of an auxiliary glow discharge with a hollow cathode with an area of 20.8×103 cm2 The experimental dependences of the probability of the appearance of cathode spots on the walls of a hollow cathode per unit time on the operating modes of the plasma emitter (pressure and type of working gas, amplitude of the auxiliary discharge current) are presented.

The paper considers the actual task of construction engineering: the elimination of harmful (undesirable) vibration phenomena in composite metal building structures and bridge cable-stayed systems – complete damping and vibration of the bridge cable-stayed system entails the calming of the entire bridge structure. Similar problems arise when designing devices that lead to dynamic rest of network antenna structures. The presentation of the material is based on the main provisions of the modern theory of optimal control of distributed differential systems with network carriers. An extensive literature is devoted to the sanctification of the research of the mentioned problem, however, an exhaustive solution of the problems of controlling elastic structures by external influences of various types (distributed, boundary, starting, and point control) and a comparative analysis of their properties did not find their place in these studies. In addition, the ways of algorithmization of previously obtained results are not always specified. The paper uses a mathematical model describing small oscillations of a spatial string system. It is convenient to use such a system and approaches to the analysis of its mathematical model as a fairly simple fundamental object when considering a more complex object, which is an elastic system of more complex elements. The results of the work are presented in a form that makes it possible to formalize the computational procedure, which is convenient for algorithmizing the process of determining the solution, and therefore for the modern application of computer technology. It remains to add that the work indicates ways to transfer the obtained results to the case of analyzing optimal control problems with carriers on multidimensional network-like domains.

The article presents the results of studies devoted to the study of the energy density distribution in the amplitude-modulated regime of electron beam generation. It is shown that in the first ≈ 50 μs of the duration of the beam current pulse, its spatial rearrangement occurs, due to the development of the arc discharge current. Thus, the rearrangement of the arc current, which develops from the axis of the system, leads to an axial diving of the emission current density and the beam current density on the target. With the development of the arc current, the energy density on the target on the axis of the system decreases and after ≈ 50 μs takes on a steady-state value, which can change only as a result of a change in the conditions for generating an electron beam or the transition to a modulated regime of electron beam generation. It has been experimentally shown using calorimetric measurements that the shape of the electron beam current pulse with its amplitude modulation with a pulse duration of more than 100 μs has little effect on the distribution of the beam energy density in the target region.

In this work, using a unique feature of the “SOLO” electron source with a grid plasma cathode based on a low-pressure arc discharge, which consists in the possibility of controlled operation of the beam power during a pulse of submillisecond duration, and, accordingly, the rate of energy input into the sample surface, we investigated the modes irradiation of samples of hypereutectic silumin. The irradiation modes had the same energy density during the first 200 μs of the pulse, equal to 20 J/cm2 and differed in different durations of further maintaining the surface temperature at 600°C for a time of up to 1 ms. The results of tribological tests and methods of diffraction microscopy of the investigated defect structure, the elemental and phase composition, the morphology of the strengthening phases of the modified layer of the hypereutectic silumin samples are presented.

The effect of solar cell fragment annealing on its noise characteristics is shown. The calculated difference in relaxation times arising from the change in noise after annealing was 30%. Measurements of noise characteristics in the dark and under illumination with a red laser with different radiation power were carried out. Close to linear dependences of noise power reduction with increasing radiation power were obtained.

The purpose of the study is to identify the municipalities of the Altai region, which is one of the leading agrarian regions of Russia, with the development potential for cooperation of small forms of farming in dairy cattle breeding. It was found that in conditions of a decrease in the number of cows in all categories of management, the proportion of municipalities in the region that have the highest and high potential for the development of consumer cooperation increases (in 2007 this group included 54.0% of all municipalities of the region, then in 2020 more than 69.8%). However, this potential has not been realized, which significantly reduces the possibility of stabilizing and increasing milk production in the region. It was concluded that consumer cooperation develops only with government support and by proactive entrepreneurs. In the areas with suitable agrarian infrastructure for the pooling non-profit associations of milk producers, the necessary infrastructure, organizational and educational conditions should be developed.

The non-Arrhenius behaviour of conductivity of phase-change materials is analysed in terms of the statistical shift of Fermi level. To show this connection, a simplified model for the density of states in a phase-change material is proposed to simulate the temperature dependence of the Fermi level. Comparison of the temperature dependence of conductivity of Ge2Sb2Te5 with the simulation results allowed estimating the position of defect levels in the bandgap.

The non-Arrhenius behaviour of Ge2Sb2Te5 conductivity is attributed to the non-linear temperature dependence of the Fermi level, assuming extended state conduction by free holes. The temperature-dependent Fermi level is shown to alter values of activation energy and prefactor for conductivity so that their exact determination becomes impossible using the conductivity data alone. However, if one assumes the temperature dependence of the Fermi level to be a parabolic function. Then, two of three model parameters can be retrieved; to obtain the third parameter one has to make an assumption about the value of prefactor for conductivity. Applying the proposed analysis scheme to Ge2Sb2Te5, reasonable values of Fermi level position are obtained and the change of Fermi level as a result of resistance drift phenomenon is demonstrated.

The paper focuses on the impact of the specialization of agricultural enterprises on the economic efficiency of producing sunflower oilseeds. The authors analyze the consequences of violating the optimal specific gravity of sunflower seeding in the plowland structure of enterprises. The paper assesses current trends in the world market of sunflower seeds and identifies the place of Russia and its main regions in the gross collection of this agricultural crop. The example of agricultural producers in the Altai Krai shows that the increase in the area of sunflower seeding and the increase in the share of plowland reduced economic efficiency and increased the negative impact of the crop on the soil. The increase in yields is mainly due to the intensification of production when ecological requirements are violated. Little use is made of the reserve for bee pollination of sunflower yields. The disruption of the crop rotation system has resulted in highly specialized enterprises losing more than 20-25% of the gross sunflower seed collection, reducing the return on invested resources. The authors argue that increasing the effectiveness of sunflower cultivation is possible under scientifically based management systems oriented towards organic farming.