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Coherent terahertz radiation has been generated in p–n heterostructures based on a-Si:H/a-SiC:H/c-Si excited by 800-nm femtosecond laser pulses at room temperature. Terahertz radiation is generated when a reverse bias voltage is applied to heterostructures. The properties of the generated terahertz radiation strongly depend on the bias voltage, which reflects the dynamics of nonequilibrium charge carriers produced by femtosecond laser pump in the heterostructure.

The appearance and rapid spread of new invasive leafhopper species Metcalfa pruinosa (Say, 1830) and Arboridia kakogawana (Matsumura, 1932) in Russia requires studying both the causes of the invasion and consequences of invasion for viticulture. Of particular interest is the study of the possible role of new species of leafhoppers in the spread of pathogenic bacteria of grape phytoplasmosis. At present, these issues are poorly studied. We characterized the variability of the BOLD fragment of the mitochondrial COI gene in the population samples of M. pruinosa and A. kakogawana from the populations of Crimea and the Black Sea coast of the Caucasus. With the help of PCR for specific genes, we searched for leafhoppers infected with bacteria of phytoplasmosis of grapes from the group of stolbur (Candidatus Phytoplasma solani) and intracellular symbiotic bacteria: Wolbachia, Rickettsia, and Spiroplasma. We found M. pruinosa only on the Black Sea coast of the Caucasus. The M. pruinosa populations are close to monomorphism. We found A. kakogawana in both Crimea and the Caucasus region. We have identified two new forms of this species in Russia. We have not found pathogenic bacteria of phytoplasmosis of grapes and intracellular symbiotic bacteria in studied leafhopper populations.

Different accelerating structures are analyzed with respect to their maximum current and shunt resistance depending on the efficiency of the structure. It is found that a structure based on a standing wave with series coupling is an optimal structure in regards to microwave power transfer to the beam.

The possibility of using millimeter-wave (MM) satellite communication lines in the Arctic to ensure reliable and high-speed communication is considered. The main problem for the application of MM waves is the possible meteorological conditions for the propagation of radio waves in the cold. Vertical profiles of meteorological data for a pair of islands in the Arctic Ocean were used to calculate molecular absorption on a possible link. A very simple model of attenuation of radio waves in rain on such a line is proposed. The satellite orbits for calculating the line attenuation margin were assumed as in the existing satellite system Gonets operating at frequencies of 300/400 MHz. The results of calculations show that satellite communications in the MM band are possible in the Arctic.

A modification of Polyak’s special method of convex optimization is proposed. The properties of the corresponding algorithm are studied by computational experiments for convex separable and nonseparable optimization problems, nonconvex optimization problems for the potentials of atomic-molecular clusters, and a model optimal control problem. Sequential and parallel versions of the algorithm have been implemented, which made it possible to solve problems with dimensions of up to one hundred billion variables.

Existing Markov models of the relaxation of quantum-mechanical systems are applicable in the approximations where the difference between eigenfrequencies is either much larger than the relaxation rates (global approach) or much lower than these rates (local approach). In this work, a model has been proposed to describe relaxation in systems where the difference between some eigenfrequencies is close to the relaxation rates. It has been shown that the master equation for the density matrix contains coefficients explicitly depending on the time in the interaction representation. Equations for the occupation numbers of the modes of the system have been derived by example of two interacting oscillators. It has been shown that occupation numbers in the proposed approach in the limits of small and large differences between eigenfrequencies compared to the relaxation rates asymptotically match the occupation numbers in the local and global approaches, respectively.

The main problems associated with the operation of reverse osmosis facilities in the treatment of groundwater for drinking water are considered and the possibilities of reducing the concentrate consumption are studied. The existing solutions for reducing the consumption of concentrate using reagent and evaporation techniques are described. The presented article is devoted to the investigation of possibilities to remove calcium carbonate from concentrate due to calcium deposition on “seed” crystals. A new technique for reducing concentrate flow is presented that consists of the operation of a membrane unit in circulation mode whereby concentrate is circulated through a “seed” reactor. Calcium and carbonate ions deposit on the seed crystals thus reducing the scaling hazard and total dissolved solid (TDS) value. A water treatment flow diagram is presented and technical parameters of membrane facilities are determined at each stage that allow one to calculate the entire technological scheme. The product flow on each membrane stage is calculated, scaling rates and calcium carbonate deposition rates are evaluated; caustic consumption and number of membrane facilities at each stage are determined. An experimental technique to determine the amount of hardness removed from the concentrate and the minimal volume of concentrate that could be reached per day is described. The main dependences are obtained and presented, which make it possible to determine the costs of electricity and reagents, types of membranes and volumes of concentrate, the rates of accumulation of sediment on the membranes, and the efficiency of removing hardness ions from water during the operation of the third-stage setup in the circulation mode.

Paramagnetic complexes containing nitric oxide (NO) have been assayed in rat heart and liver tissues by EPR spectroscopy to investigate the time variation of NO production during postnatal development. Nitric oxide levels have been assessed from the intensity of a characteristic EPR signal belonging to the (DETC)2–Fe2+–NO complex. The results show that the content of NO in liver tissues increases within the age interval from 28 to 56 days but does not change significantly in postadolescence. In heart tissues, the nitric oxide level increases in adulthood compared to puberty. The NO level in the rat liver is significantly higher than in heart tissues in all studied age groups.

The OCP and PCB contents in the tissues of beluga whales (Delphinapterus leucas) from the Russian Arctic have been studied for the first time. Skin and subcutaneous adipose tissue samples collected in the White, Kara, and Bering seas in 2012–2017 were analyzed for the animals of different age and sex (n = 22). 4,4'-DDE dominated among the OCPs analyzed; the main PCB congeners were PCB-138+PCB-158 and PCB-153 + PCB-168, which was also typical of other Arctic marine mammals. The highest concentrations and widest range of these compounds were found in beluga whales from the White Sea (4,4'-DDE: 3778.3 ± 4856.3 ng/g lipids; ranging as 33.2–16 007.8 ng/g lipids; PCB-138 + PCB-158: 1270.1 ± 1528.8 ng/g lipids; ranging as 127.6–4957.4 ng/g lipids; PCB-153 + PCB-168: 1144.1 ± 1230.2 ng/g lipids; ranging as 113.0–4515.2 ng/g lipids). The lowest concentration was found in the beluga whales from the Anadyr estuary of the Bering sea (4,4'-DDE: 1003.3 ± 1422.1 ng/g lipids; ranging as 186.0–3125.0 ng/g lipids; PCB-138 + PCB-158: 95.0 ± 99.2 ng/g lipids; ranging as 29.9–242.1 ng/g lipids; PCB-153 + PCB-168: 114.8 ± 118.8 ng/g lipids; ranging as 35.4–290.9 ng/g lipids). The biological parameters of the sampled animals, the features of PCB and OCP transport pathways, as well as regional environmental pollution, were considered the main reasons for the observed geographical variability of pollutant concentrations in beluga whales.

A one-dimensional random laser consisting of a disordered system of layers with different permittivity values, some of which contain an active medium, has been considered. Such a system has been modeled as a chain of Fabry—Perot cavities separated by nonresonant layer subsystems. It has been assumed that light passing through such subsystems is weakened. The properties of partial eigenmodes of such cavities with increasing pump power of the active medium have been studied. It has been shown that the pulling of the mode frequencies that occurs with increasing pump power causes the formation of coupled cavity chains and an increase in the average volume of partial eigenmodes.

Most of the software model checker tools do not scale well on complicated software. Our goal was to develop a tool, which provides an adjustable balance between precise and slow software model checkers and fast and imprecise static analyzers. The key idea of the approach is an abstraction over the precise thread interaction and analysis for each thread in a separate way, but together with a specific environment, which models effects of other threads. The environment contains a description of potential actions over the shared data and synchronization primitives, and conditions for its application. Adjusting the precision of the environment, one can achieve a required balance between speed and precision of the complete analysis. A formal description of the suggested approach was performed within a Configurable Program Analysis theory. It allows formulating assumptions and proving the soundness of the approach under the assumptions. For efficient data race detection we use a specific memory model, which allows to distinguish memory domains into the disjoint set of regions, which correspond to a data types. An implementation of the suggested approach into the CPAchecker framework allows reusing an existed approaches with minimal changes. Implementation of additional techniques according to the extended theory allows to increase the precision of the analysis. Results of the evaluation allow confirming scalability and practical usability of the approach.

Results of analysis of nitric oxide and copper content in rat liver and hippocampus after brain ischemia modeling are provided. The studies are carried out using the electron paramagnetic resonance spectroscopy method with spin traps. It was shown that, the day after brain ischemia modeling, nitric oxide content in hippocampus decreases on average by 50% and a tendency toward its decrease was observed in liver tissues. Two days after brain ischemia modeling, nitric oxide content in the brain recovered and a significant increase by 46% against control indices was observed in the liver. On the second day of the postischemic period, the copper content, which is associated with superoxide dismutase content, increased on average by 2.5-fold in the liver. No significant changes in copper content was found in the hippocampus.

An S-band klystron of 50 MW power is being developed at the Budker Institute of Nuclear Physics. At the moment, all the necessary calculations have been made and cathode assembly, bunching cavities, the collector, the solenoid, and the cooling system have been completed. The klystron has been tested in a diode mode without bunching cavities, which were brazed separately. Cavities have been measured and tuned at the required frequencies and installed on the prototype of the klystron. Currently, a fully finished prototype is being tested in order to obtain RF power.

An Injection Complex (IC) was designed in Budker Institute of Nuclear Physics in Novosibirsk in frame of a program of super high luminosity electron-positron facility VEPP-5. The stability of its operation is determined, among other things, by an injection-extraction system and, consequently, by generators of inflectors. For stable operation of the Injection Complex, these generators must produce pulses with maximum amplitudes of the output voltage of 50 kV and current in the load of the inflector 2 kA, the instability of the flat top less than 5% and its duration in the range from 20 to 92 ns; temporary stability of the generator should be ±2 ns and the output pulse’s front—less than 50 ns. In addition, it must be able to adjust the output voltage amplitude in the range of 10–100% [1]. This paper presents the results of the design sample of a generator of high-voltage nanosecond square pulses based on SOS-diode and the high-current cold cathode thyratrons (pseudospark switches).

—The principle of operation of a distributed beam-loss monitor based on the Cherenkov radiation in optical fiber is considered. The monitor allows real-time monitoring the distribution of the beam loss along the entire accelerator. The methods for increasing the spatial resolution of the monitor implemented on the e–e+ Injection Complex at the Budker Institute of Nuclear Physics are experimentally studied. For a 15-m-long quartz fiber with a diameter of 550 μm and a microchannel plate-based photomultiplier as a radiation detector, a spatial resolution of 0.5 m is achieved.

The VEPP-5 injection complex, consisting of two linacs and a damping storage ring, delivers electron and positron beams to the VEPP-4M and VEPP-2000 colliders operating at BINP. Over three years of injector operation, its efficiency has significantly increased and the maximum positron-storage rate has reached 1.2 × 1010 s–1. This progress was reached through tuning the constituent machines, upgrading the accelerator technology, and deploying a new 11-MHz station of RF cavities. By the start of the next running season, a new electron gun with a significantly increased maximum current and cathode lifetime will be installed.

Composite films based on CH3NH3PbI3 organometallic perovskite and mixed cellulose ester (CE) were studied using terahertz (THz) spectroscopy in the time domain. It is established that the introduction of CE into CH3NH3PbI3 precursor significantly modifies the parameters of perovskite in the THz range and improves stability of the composite films. In particular, CE addition to the perovskite composite film leads to significant weakening of absorption bands in the region of 1–2 THz related to the excitation of low-frequency oscillatory modes in CH3NH3PbI3 molecules. This can be explained by damping of these modes on CE molecules enveloping the perovskite molecules.

A comparative analysis of the current content of petroleum hydrocarbons in various components of the ecosystem was performed to assess the ecological state of the southeastern part of the Onega Bay (White Sea) that suffered from a spill of fuel oil in 2003. The analysis showed relatively low levels of petroleum hydrocarbon concentrations: from 0.34 to 4.55 mg/kg, with a median of 1.41 mg/kg in bottom sediments; from 9.41 to 14.25 mg/kg, with a median of 12.30 mg/kg in tissues of benthic organisms; and below 1 MPCfishery (the maximum permissible concentration) in water. The records of low concentrations of bacteria that use petroleum hydrocarbons (fuel oil) allow us to conclude that the state of the examined ecosystem is close to the natural condition.