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Radiolytic transformations of TODGA (N,N,N',N'-tetra-n-octylamide of diglycolic acid) in Isopar-M significantly depend both on the addition of alcohol (n-nonanol or n-decanol) and on the saturation of the solution with 8 M HNO3. Fragmentation of TODGA molecules is the dominant radiolytic process. Compared to acid-free solution, radiolysis in the presence of HNO3 results in a much lower yield of N,N-dioctylacetamide formation, while 2-hydroxy-N,N-dioctylacetamide remains the main degradation product of TODGA. The acidification of the solution promotes a lower radiolytic degradation of TODGA, but expands the range of final radiolysis products, in particular, due to the participation of NO2 and NO radicals in radiation-induced reactions. Alcohol serves as a source of alkoxy radicals, which are highly reactive towards TODGA. In the presence of nitric acid, a significant portion of alkoxy radicals decay in reactions with NO2, NO, and acyl radicals and, thus, do not participate in the decomposition of TODGA.

Background. Granulomas of the vermilion border of the lips (GVBL); as a complication of lip tattooing; inevitably poses cosmetic problems. Surgical excision and cryodestruction are associated with an increased risk of scarring and recurrence of GVBL. Laser therapy can selectively destroy a pigment and achieve the desired cosmetic result with minimal risk of side effects. So laser treatment was reported to be a more relevant method of treatment of GVBL. Aim. To evaluate the effectiveness of treatment of GVBL with copper vapor laser (CVL) radiation. Case report. 39-year-old female patient; without manifestations of systemic sarcoidosis; reported a 2-year history of granulomas of the lips vermilion border. She had a permanent makeup cosmetic tattoo before the onset of granulomas after lip tattooing. Histopathological examination revealed the presence of pigment in the upper and middle layers of the dermis. GVBL treatment was performed using a CVL during a single procedure; with an average CVL power of 0.60.8 W; with a ratio of 3:2 at wavelengths of 511 nm and 578 nm; exposure time 0.3 s. Light spot diameter 1 mm. CVL treatment led to a pronounced elimination of all GVBL without side effects within five years. Discussion. CVL allows a combined mode of exposure; consisting of grinding large granules of pigment to sizes that can be absorbed by the lymphatic system and suppressing VEGF expression using radiation with a wavelength of 578 nm. Conclusions. The CVL treatment provided an excellent cosmetic result due to selective photodestruction of the pigment and complete remodeling of the vascular bed associated with GVBL. The high clinical efficiency of eliminating post-tattooing foci of GVBL using CVL without side effects allows us to suggest this method for dermatologists and cosmetologists as a highly effective and inexpensive way to eliminate complications of permanent makeup.

The results of experimental studies and numerical simulation of the fragmentation of aluminum alloy projectiles on a tungsten mesh bumper at impact velocities of up to 7 km/s are presented. The projectiles are accelerated by a two-stage light-gas gun. X-ray photography is used to observe the state of a projectile before its impact on the mesh bumper and the process of its fragmentation. The parameters of the cloud of fragments of the projectile are recorded using a thick witness plate made of AMg6 alloy placed behind the mesh bumper. Numerical simulation is performed by the smoothed particle hydrodynamic (SPH) method. Specific features of the morphology of the cloud of fragments are pointed out, and the velocities of the fragments in different parts of the cloud, as well as the arising cumulative effect, are estimated. The experimental results are compared with the results of numerical simulation.

An analysis of various schemes for coolant motion in a nuclear reactor with spherical microfuel elements (coated fuel particles, or pebbles) is presented. The conditions under which it is possible to reduce the pressure losses in the coolant keeping all the advantages of the spherical microfuel elements versus the fuel rods are considered. The rate of coolant flow and the pressure losses in the reactor during its longitudinal-axial and radial motion through the pebble bed are determined. An interchannel scheme of coolant motion is proposed, and the conditions are defined for which it has advantages over the radial scheme.

—We present the results of the laboratory studies on fluid initiated fracture in the samples of porous-fractured rocks that have been initially saturated with a pressure-injected fluid and then tested under increasing fluid pressure in saturated rocks. The tests were conducted at the Geophysical observatory “Borok” of Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences. The laboratory is equipped with electrohydraulic press INOVA-1000. The experiments were conducted on the rock samples with substantially different porosity. The tested samples were made of Buffalo sandstones, granites from the well drilled in a seismically active region and of granites from the well in the Voronezh crystalline massif. The permeability of granite samples was varied by their controlled artificial cracking by successive heating and cooling. The experimental procedure was set up in the following way. A preliminarily dried sample was initially subjected to uniaxial loading in uniform compression (confining pressure). Loading was performed at a constant strain rate until the moment when the growth rate of acoustic emission (AE) activity began to accelerate which indicated that the stress level approaches ultimate strength. Since that, the loading rate was decreased by an order of magnitude, and water was infused into a sample from its top face. The bottom end of a sample was tightly sealed and impermeable to water. After this, the pore pressure in the sample that had got saturated with water to that moment was raised in steps whose amplitudes were varied. The obtained results of the laboratory studies show that the character and intensity of fluid initiation of fracture markedly differ under primary fluid injection into the porous-fractured samples and under the subsequent increases of the pore pressure in the saturated samples. The time delay of acoustic response relative to fluid initiation and the amplitude of the response proved to be larger in the case of water injection into dry samples than in the case of raising the pore pressure in saturated samples. The AE response to the decrease in the pore pressure was also detected in the experiments. The theoretical analysis of fluid propagation in a pore space of an air-filled sample in the model with piston-type air displacement has shown that in the case of water injection into a dry sample, the fluid pressure front propagates more slowly than in the saturated sample.

—The spectrum is obtained and the time dependences of fractoluminescence signals upon fracture of the surface of quartz are studied. The analysis of the obtained data has shown that at fracture, clusters of four cracks having a size of a few nm appear. Crack formation is associated with the destruction of barriers precluding the motion of dislocations along the sliding planes. The distribution of cracks by sizes (surface areas of crack walls) obeys the Gutenberg–Richter law.

We designed, implemented, and characterized differential amplifiers for cryogenic temperatures based on Si bipolar junction transistor technology. The amplifiers show high gain values of more than 60 dB at 300, 77, and 48 K. The minimum voltage noise spectral density was achieved at 77 K and corresponded to 0.33 nV/Hz0.5 with a flicker noise of 20 Hz. The maximum voltage gain was 70 dB at 77 K for a frequency range from DC to 17 kHz. We experimentally show that the parallel differential circuit design allows for a reduction of the voltage noise from 0.55 to 0.33 nV/Hz0.5 at 77 K.

—The issues concerning the relationship between two self-similarity parameters—the Gutenberg–Richter b- and Omori p-values—in the aftershock sequences are explored. In the laboratory experiments, under fracture initiation in the rock by sharp jumps in the axial stress, a correlation between the p- and b-values is revealed in the fracture relaxation regimes similar to aftershocks. The correlation observed in the experiments on water-saturated sandstone samples with the preliminarily formed faults is negative and clearly pronounced. The correlation in the case of dry samples of migmatite and concrete proved to be positive but its statistical significance is lower than for the wet samples. The analysis of the literature data on detecting the connection between parameters p and b in the natural aftershock sequences shows that the reported results are heterogeneous. Some authors conclude that these parameters are connected and that both positive and negative correlation is noted between them. Other authors present evidence suggesting the absence of any correlation. Our study of the natural aftershocks based on the data of regional earthquake catalogs has shown that the statistical estimates of the Gutenberg–Richter and Omori parameters are fairly sensitive to the quality and homogeneity of the input data. The key factors affecting the estimation quality of these parameters are established, and the procedure for selecting the aftershock catalogs for subject analysis is developed. The results of statistical estimating the Gutenberg–Richter and Omori parameters in the aftershock processes in the regions with different types of the tectonic regimes—subduction zones and regions of shear transform faults—have shown that that the correlation of these parameters in the subduction zones can be positive and negative either. In the zones of the transform faults, the connection between these parameters is not detected. Our study generalizes K. Scholtz’s idea that the Omori law can be explained by the superimposition of the relaxation processes having different relaxation times. According to the generalized model, the different sign of the correlation between the self-similarity parameters in the aftershock processes correspond to the different relaxation mechanisms with different types of the dependence of the relaxation time on the “size” of the relaxator. It is currently unclear which particular mechanisms are implemented in the aftershock processes. The relationship between the Omori and Gutenberg–Richter parameters revealed by our laboratory experiments and field studies (positive correlation, negative correlation, or lack of correlation) may indicate the implementation of different relaxation mechanisms in some or other particular conditions.

The effect of an electron beam on the toxic microalgae Cochlodinium polykrikoides and Alexandrium catenella, which are involved in the phenomenon of seawater blooming known as red tides, has been studied. This annual disaster causes mass intoxication and death of marine life. Electron-beam irradiation at an absorbed dose of to 1 kGy leads to inactivation of more than 2/3 of the microalgae population due to disruption of cell walls, damage to chloroplasts, and cell aggregation. Radiolysis destroys paralytic toxins, including the most dangerous of them. Because of low doses and the ease of irradiation, the electron-beam treatment of water can be a promising method for the inactivation and detoxification of phytoplankton involved in red tides.

The radiolytic degradation of 2,4,6-trinitrotoluene and hexahydro-1,3,5-trinitro-1,3,5-triazine in individual aqueous solutions and in real wastewater was studied using the jet mode under an accelerated electron beam. The degree of mineralization of organic compounds and their biodegradability increased due to successive denitration, oxidation, and decarboxylation processes in solutions. The yields of radiolytic degradation of 2,4,6-trinitrotoluene and hexahydro-1,3,5-trinitro-1,3,5-triazine were about 0.027 and 0.064 μmol/J and the corresponding half-life doses were as high as 10 and 1.8 kGy, respectively. The high efficiency of the removal of 2,4,6-trinitrotoluene from real wastewater with the sequential use of coagulation, irradiation, and biological treatment was demonstrated.

The method of differential scanning calorimetry has been used to study the thermal stability of unirradiated and irradiated extractive mixtures containing 0.15 М of the extractive agent N,N,Nʹ,Nʹ-tetra-n-octyldiglycola (TODGA) in Isopar-M diluent with n-decanol or n-nonanol in relation to the sequence of contact with nitric acid. It was shown that heating within the range 50–250°С causes exothermic thermochemical processes in the starting extractive systems in the presence of nitric acid. The radiolysis stimulates the decomposition of an organic solution with release of gaseous products and changes both the thermal stability of the solutions under study and their interaction with nitric acid.

A method for the measurement of the complex permittivity of insulators using a microwave coaxial photonic crystal is proposed and implemented. The method is based on a solution to an inverse problem using minimization of the difference of experimental and calculated frequency dependences of the transmission and reflection coefficients at the defect-mode frequency in the band gap of a photonic microwave crystal containing a structure with the parameters that must be determined. An unambiguous solution to the inverse problem can be obtained using a defect mode in the band gap at the frequency of which a maximum of the standing wave is obtained in the region of the structure under study.

The review is devoted to the use of ionizing radiation for the processing of polymer wastes including the application of radiolytic effects to the sorting of plastics; an increase in the compatibility of plastics with cement, asphalt, and other materials; the destruction of high-molecular-weight wastes; the synthesis of multicomponent polymer composites; the production of monomers for the synthesis of conventional and alternative plastics; the manufacture of antioxidants; the processing of inseparable mixtures of natural and synthetic polymers; etc. The radiation-induced processes of crosslinking, graft polymerization, oxidation, degradation, and high-temperature conversion in the recycling of polymer wastes are considered.

This article discusses work on assessing the digestibility of a concentrate of Hermetia illucens larvae in fish with gastrointestinal digestion (rainbow trout Oncorhynchus mykiss, Russian sturgeon Acipenser gueldenstaedtii, red tilapia Oreochromis mosambicus × O. niloticus). It was found that this digestibility index of the larvae concentrate was 67–74%. At the same time, fish species consumed larvae protein at 91–97%, the digestibility of residual fat was 90–94%, and easily hydrolyzed carbohydrates amounted to 52–68%. Сhitin of H. illucens was digested 25–35% and did not adversely affect the digestion of protein and fat in the fish species studied. The digestion rates of the H. illucens larvae concentrate, protein, and easily digestible carbohydrates in O. mosambicus × O. niloticus are statistically significantly higher than in Onc. mykiss, while in A. gueldenstaedtii they were intermediate in comparison with tilapia and trout. This corresponded to the duration of food passage through the intestinal tract, which in O. mosambicus × O. niloticus, Ac. gueldenstaedtii, and O. mykiss came to 7.8, 9.6, and 15.7 hours, respectively. Fat and chitin were digested by red trout significantly more efficiently than other fish species. This corresponded to the duration of food passage through the intestinal tract, which for tilapia, sturgeon, and trout came to 7.8, 9.6, and 15.7 hours, respectively. The degree of digestibility of fat and chitin by trout was significantly higher than that of other fish species.

During the prebiotic era, radiolytic transformations in the oceans played a key role in purifying water from toxic impurities and, thus, played a role in the formation of the aquatic environment of our planet, making it suitable for the emergence of life. Today, the planet again faces the challenge of how to provide people with clean water. Therefore, it is reasonable to look back at past historical stages and again consider the possibility of neutralizing pollutants in water by means of radiolysis, which has already been tested by time. Modern radiolytic treatments can be much faster and safer thanks to the advent of powerful electron accelerators and high-rate electron beam treatment (ELT) of water and wastewater. Radiolytic treatment of water using accelerated electrons corresponds to the essence of advanced oxidative technologies and green chemistry. The ELT of water instantly generates a high concentration of short-lived radicals that can quickly neutralize and decompose chemical and bacterial pollutants. Due to the ability of accelerated electrons to penetrate into a substance, ELT provides the decomposition of both dissolved and suspended pollutants. The cleaning effect of ELT is due to the ability to inactivate toxic and chromophore functional groups, transform impurities into an easily removable form, damage the DNA of microorganisms and their spore forms, and increase the biodegradability of organic impurities. The use of ELT in water treatment provides significant savings in chemical reagents, thereby improving quality and reducing the number of cleaning steps. The compactness, high degree of automation of the equipment used, energy efficiency, high productivity, and excellent compatibility with traditional water treatment methods are important advantages of ELT. Unlike conventional chemicals, the excess radicals generated in the ELT process are converted back to water and hydrogen; thus, the chemical and corrosive activity of water does not increase. Equipping research institutes with electron accelerators, developing cheaper accelerators, and granting government support for pilot projects are key conditions for introducing ELT into water treatment practice.

The effect of the boiling state on the reaction mechanism of 11 free radicals formed upon irradiation of 1-propanol with 8 MeV accelerated electrons is considered. Compared to radiolysis at room temperature, radiolysis at boiling results in an increase in 1-propanol degradation yield from (10.1 ± 0.9) to (13.3 ± 0.9) molecule/100 eV. Boiling shows the largest effect on the radilytic cleavage of the C(1)–H and C(2)–H bonds and almost doubles the yield of hydroxyalkyl radicals. In particular, the boiling effect is due to the suppression of the cage effect, a decrease in the relative role of intermolecular relaxation, and an increase in the processes of radicals exchange and combination.

The postradiation thermal decomposition of lignosulfonates and krill chitosan has been studied using differential scanning calorimetry and thermogravimetry. It has been shown that irradiation facilitates a more than twofold decrease in the yield of charred residue in chitosan but only slightly affects the thermolysis of lignosulfonates.

Electron beam treatment would cause conversion of trinitrotoluene and 1,3,5-trinitrohexahydro-1,3,5-triazine into biodegradable products and thus can be employed for the practical decontamination of ‘red’ wastewater in combination with bio-treatment.

—The growth rate and size of microcracks formed in the surface layer of basalt and tonalite (granodiorite) at friction are studied using luminescence. It is found that upon breaking of crystal lattices of labradorite and quartz contained in these rocks, triboluminescence signals arise. Each signal corresponds to an embryo microcrack whose surface contains electronically excited free radicals ≡Si–O–, Fe3+ ions, and electron traps. The average growth rate of embryo microcracks in basalt varies from ~0.6 to ~1 km/s and in tonalite, from ~ 0.7 to ~1.3 km/s. The sizes of embryo microcracks in basalt range within ~3 to ~5.5 μm and in tonalite from ~3.5 to ~6.5 μm.

Samples of composite second-generation high-temperature superconducting (HTS) tapes based on the GdBCO (123) compound have been irradiated in a pulsed electron accelerator (system Terek-2, GPI RAS) through a tantalum target in order to determine how the thermal and shock loads arising on the tantalum-HTS interface affect the superconducting parameters of HTS tapes. Scanning Hall magnetometry was applied to characterize HTS samples subjected to electron irradiation. The thermal modes and shock load in a composite superconductor under irradiation are estimated as functions of the energy absorbed by the target. At a silver surface temperature equal to the melting point, the critical current decreases by 87% from the initial value. At lower irradiation energies, the decrease in the critical current is smaller. The role of the temperature effects and shock waves under this irradiation is discussed.

A change in the operation mode of a plasma maser with a pulse duration of 40 ns from a noise amplifier to a feedback self-oscillator at a power level of up to 10 MW has been experimentally demonstrated for the first time. In the noise-amplifier mode, the radiation power is distributed almost uniformly in a frequency range from 3 to 9 GHz. In the self-oscillator mode, the emission spectrum contains characteristic frequencies of longitudinal oscillation modes of plasma—beam cavity.

Thermally stimulated rock failure has been actively studied for over 30 years for solving both fundamental and applied problems. At the same time, there are features that make it difficult to obtain information on the development of thermal compared to mechanical damage. The article discusses three main problems: the small number of recorded acoustic emission pulses, the difference in thermal conditions during heating and cooling, and the high level of interference from conventional heating control systems. The article analyzes ways to solve these problems and proposes and develops an improved laboratory setup and methods for studying thermally stimulated rock failure.

The combination of dry distillation with irradiation with accelerated electrons can serve as a productive method for the conversion of waste plastics and their mixtures with cellulose wastes into liquid organic products. It was found that, on the combined distillation, plastics were mainly converted into soft wax and organic liquid. In turn, the lignocellulose fraction of mixed wastes was converted into furans (which can serve as raw materials for the subsequent synthesis of “green” plastics) and, in part, into phenolic inhibitors of reverse polymerization. The combined distillation is characterized by a lower yield of unsaturated and gaseous products, and it takes place at lower temperatures.

The growth rate and size of microcracks, formed in the surface layer of a heterogeneous natural solid (sandstone) under friction were studied via triboluminescence. It was discovered that destruction of the crystal lattice of plagioclase and quartz, composing sandstones, induces triboluminescence signals. Each s-ignal corresponds to a microcrack, whose surface contains electronically excited free radicals ≡Si–O– and Fe3+ ions. The size and growth rate of microcracks were assessed by means of analysis of the rate and duration of the buildup of these signals. The growth rate of microcracks turned out to be less than the elastic wave velocity (~700 m/s) and varied from ∼380 to ∼650 m/s. The size of microcracks varied from ∼4 to ∼7 μm. It was assumed that the variation in the size and growth rate of microcracks were caused by differences in value of the barriers, upon breaking which the microcracks appear.

Infrared-reflection and transmission spectroscopy was used to study the mineral composition of a shear fracture surface in a core recovered from a well in the seismically active Koyna-Varna region in western India, which is associated with reservoir-induced seismicity. Methods for conducting comprehensive experimental studies of the mineral composition of shear fracture surfaces in rocks are described. The experiments demonstrated the wide possibilities of these techniques and allowed us to obtain new results on shear fractures, which are important for further research on the physics of earthquake foci. It is established that the shear fracture surface is a three-layer structure. The upper layer contains only glauconite nanocrystals. The layer beneath it contains, in addition to glauconite, calcite and montmorillonite crystals. The total thickness of these layers is about 600 µm. Below these layers is the host rock, which contains calcite, dolomite, and glauconite. The number of illite–smectite layers in glauconite nanocrystals has been determined. The upper layer contains nanocrystals consisting of ∼30 layers. In the second layer, the crystals of this mineral contain ∼25 layers. Finally, in the host rock, glauconite crystals make up ∼20 layers.

Pectin, starch, gelatin, and wheat flour in dilute aqueous solutions undergo irreversible aggregation and sedimentation even at absorbed doses lower than 1 kGy. Irradiation narrows the size distribution of suspended particles in solution. It is noted that the effect of irradiation is caused not only by intermolecular crosslinking but also by the electrostatic effect of charged radiolytic intermediates. The decrease in the aggregative stability of gelling substances on the irradiation of their dilute solutions can be used for practical wastewater treatment and for the target-oriented synthesis of aggregates with a specified particle size distribution.

The effect of electron beam irradiation on the dry distillation of plastics waste and their artificial mixtures with lignocelluloses as well as refuse derived fuel (RDF) was studied. It was found that irradiation makes it possible to reduce the temperature of dry distillation and increase the yield of wax/oil from plastics. Wax/oil obtained via the radiation-thermal degradation of plastics contains more of saturated components. Wax/oil yield is at least 2/3 of the initial RDF sample. Radiation-thermal degradation of the cellulose fraction of RDF produces mainly derivatives of furans.

The yield of radiolytic degradation of 1-propanol is 13.3 ± 0.9 molecules/100 eV in a boiling state and 10.1 ± 0.9 molecules/100 eV in ambient conditions when irradiated with 8 MeV accelerated electrons. Boiling increases the yields of diols by 1.7 times and of heavy monohydric alcohols arising via the radical combination by 1.3 times. At the same time, due to boiling, the total yield of methanol and ethanol decreases 2.1 times, and the yield of aldehydes and hydrocarbons − 1.3 times. Boiling accelerates the dissociation of some radicals and radical-cations, facilitates the radical exchange and favors a combination of hydroxypropyl radicals. However, both in liquid and boiling alcohol, the total yield of splitting of C–H bonds remains approximately twice as high as C–C bonds.

A feasible design of a system with an allowed band with near-unity frequency-independent transmission utilizing the reflective properties of photonic crystals with dielectric filling and resonant irises in a setup with a Y-circulator is demonstrated. The existence of impurity modes of oscillation damping in the allowed band of this photonic crystal with disturbed periodicity is confirmed. Bandstop filters with parameters controlled by n–i–p–i–n diodes are constructed based on photonic crystals with resonant irises. These filters have a rejection level of >43.0 dB in the stop band and losses below 0.8 dB outside of it.

The Kurai Basin of Gorny Altai is located in the area of high seismic activity, which is involved in the focal zone of the 2003 M7.3 Chuya earthquake. Its aftershock process has not ceased yet, and shows the likelihood of major seismic events. The seismic monitoring records of the last 15 years after the devastating earthquake show the state of stress in the basin. A comprehensive field database has been consolidated from the studies of direct and alternating currents by electromagnetic methods, including transient electromagnetic sounding, vertical electrical sounding, and electric field tomography. Using a combination of the research techniques and the method of interpretation based on data inversion, it becomes possible to select optimal models, ensure higher reliability, and improve the contents of the study. The available seismological data are used to identify the zones of concentration of seismic events in the southern mountain frame of the Kurai Basin. Our study aims to determine and clarify the geoelectric structure of the southern troughs. The first section of the Southwestern trough is constructed, and the latitudinal fault boundaries of the Eshtykel graben are confirmed. A comparison of electromagnetic and seismic data for 2015 shows that the earthquake epicenters were mainly confined to the submeridional fault zones. In our study of the Southwestern trough, it is established that most of the earthquakes concentrated in active fault structures separating the blocks of varying depths, which are identified from the geoelectric data. The southern piedmont troughs of the Kurai Basin are cut by numerous faults of latitudinal and submeridional strikes.

To carry out effective plant protection measures, it is necessary to take into account all the factors affecting the quality of the crop. The aim of our research was to study the degree of development of leaf diseases of winter wheat and the rate of infestation of crops, depending on the tillage method. The studies were carried out in 2019-2020 at the experimental plots of “Kuban educational farm” in Krasnodar. For the research, four experimental plots with Steppe variety of soft winter wheat were created, where various soil cultivation systems were applied: 1 - No-Till (zero technology), 2 - moldboard-free technology, 3 - recommended, 4 - moldboard technology. The article presents data on the degree of development of diseases and the degree of infestation of winter wheat plants in the crops of test plots with various tillage systems. It was found that the most preferable is the use of the recommended type of treatment, since with it the least number of diseases develops and the degree of development of pathogens is reduced by 2-3 times in comparison with other options. The influence of the tillage method on the number and composition of phytopathogen spores was revealed.

A new genus, Karakumosa gen. nov., is established to accommodate nine central Asian species of burrowing wolf spiders, of which seven are diagnosed and described as new: K. badkhyzica sp. nov. (♂♀, southern Turkmenistan), K. gromovi sp. nov. (♂♀, southern Uzbekistan), K. repetek sp. nov. (♂♀, eastern Turkmenistan), K. shmatkoi sp. nov. (♂♀, northern Ciscaspian region and Azerbaijan), K. tashkumyr sp. nov. (♂, Kyrgyzstan), K. turanica sp. nov. (♂♀, Turkmenistan), K. zyuzini sp. nov. (♂♀, Uzbekistan). Two generic transfers are proposed: Karakumosa alticeps (Kroneberg, 1875), comb. nov. and K. medica (Pocock, 1889), comb. nov. (both ex HognaSimon, 1885). Lectotypes are designated for Tarentula alticepsKroneberg, 1875 (♂) and T. medicaPocock, 1889 (♂). The localities of all Karakumosa species are mapped, and an identification key is provided as well. A short overview of the fauna and diversity of the fossorial Lycosidae of Central Asia is given.

This article describes a picosecond solid-state pulsed system, where the input pulse from the generator with a semiconductor opening switch (SOS) is amplified in power and decreases in duration by ferrite gyromagnetic lines. The lines operate in the Magnetic Compression Line (MCL) mode, which occurs at close values of the input pulse duration and the period of the oscillations generated in the line. The energy compression system contains three successive stages—MCL1–MCL3 lines. For an input pulse power of 6 GW (490 kV, 40 Ω) and a duration of 7 ns, pulses of 54 GW (1.62 MV, 48 Ω) and a duration of 170 ps have been achieved at the MCL3 output. Compared to the parameters of the input pulse, the voltage rise rate has been increased ∼130 times up to 14.8 MV/ns, and the power rise rate has been increased ∼350 times up to 0.7 TW/ns. A numerical simulation of the MCL3 line operation in which the maximum electric and magnetic fields are realized (>2 MV/cm and >500 kA/m, respectively) has been carried out. The inner structure of the process of power amplification during the electromagnetic wave passage along the line has been demonstrated. First, the front of the input pulse is sharpened, and then, after the excitation of the oscillations, the process of power amplification begins, followed by the pulse amplitude reaching the saturation region.

The copper vapor laser (CVL) generating two wavelengths, one of which corresponds to the high absorption of melanin (511 nm) and the other to maximum absorption of oxyhemoglobin (578 nm), has been proven to be efficient for the treatment of pigmented and vascular skin lesions.

Laboratory experiments on studying the aftershock regime are carried out on sandstone specimens at different levels of axial loading and uniform compression and at constant pore pressure. The aftershock sequences are modeled by the scenario of stepwise increasing axial loading of a specimen with strain control, which ensures the regular generation of aftershock sequences. The experiments are conducted on intact specimens and on those with preliminarily formed shear macrofractures simulating natural faults. The multichannel recording of the signals of acoustic emission (AE) during the experiments allowed locating the AE sources. Several types of the dependence of the parameters of relaxation of the acoustic activity—parameters p and c of the modified Omori law and the Gutenberg–Richter b-value—on the level of acting stresses are revealed. The b-value decreases with the growth of axial stresses at all levels of uniform compression. In the case of a fracture on the preexisting fault, the Omori relaxation parameter p increases with the growth of axial stresses; parameter c—the time delay before the onset of relaxation—decreases with the growth of axial stresses and increases with the rise of the level of uniform compression. In the case of a fracture of an undamaged specimen, parameter p remains unchanged with the growth of axial stresses, whereas parameter c increases slightly. Parameter variations in the case of a complex stress state with both varying deviatoric (differential stresses) and spherical parts (effective pressure) of the stress tensor take on a unified form when expressed in terms of Coulomb stresses. It is hypothesized that the time delay of the relaxation of the aftershock activity is determined by the kinetics of a fracture in accordance with the kinetic concept of strength in solids. This hypothesis is supported by the exponential dependences of parameter c on stresses and the effective strength of the medium which are revealed in the experiments. Under this hypothesis, based on Zhurkov’s formula for the durability of materials, it is possible to unify the dependences of parameter c on the Coulomb stresses at different effective strength values. The obtained parameter estimates for the dependence of c on strength and stresses suggest that the c value is determined by the difference of the strength and the acting stresses, thus indicating how far the stress state of the medium is from critically corresponding to the ultimate strength.

—Luminescence caused by friction of heterogeneous solids (basalt and granite) was investigated, the spectra are recorded, and the dynamics of the luminescence intensity were studied. Under friction, the crystal lattices of these bodies are destroyed, and the luminescenting ≡Si–O– free radicals and Fe3+ ions and electron traps located on the surface of microcracks are formed. The dynamics of accumulation of microcracks is investigated at a time resolution of 2 ns, and their sizes determined to be about 6–10 μm.

Exposure to accelerated electrons makes it possible to change the properties of polymeric and composite materials on the surface and in a layer of a given depth. Ionization generates various reactive species, such as electrons, free radicals, ions, and excited molecules. These species can be used to initiate the formation of block and graft copolymers, latexes, and regular and irregular macromolecules and affect the functional properties of materials and their protective layers in a targeted fashion. Electron-beam technologies are being increasingly used in the design of improved and unique materials with desired properties of surface layers.

The radiation-induced degradation of cellulose is analyzed taking into account the effect of temperature on the formation and interconversion of macroradicals. Non-chain depolymerization, consisting in the random cleavage of glycosidic bonds, occurs at low and moderate temperatures. As a result, oligomeric polysaccharides are formed in which the C:O:H atomic ratio is only slightly different from the original one. When the hydrogen bonds disappear and the fragmentary radicals are thermally generated, the depolymerization can proceed via the chain mechanism. Another mechanism, which we term self-disassembly, consists in consecutive shortening the polymer chain from its end at pre-pyrolysis temperatures. It is realized via the dehydration of macroradicals and leads to the elimination of monocyclic furans.

A computer simulation approach to sintering of low-temperature ceramics has been developed within the framework of the micromechanics of heterogeneous media. It is taken into account that the reinforcement of the refractory component can be formed at different structural levels determined by the particle fraction size. The formation of the reinforcement of interacting refractory particles in individual sintered layer mesovolumes causes the pore structure formation, and the heterogeneous pore distribution through the mixture layer thickness in the initial compact determines the shrinkage anisotropy of the sintered ceramics. The conditions are determined in which the reinforcement of refractory components is formed at different structural levels. An initial block of layers formed of a mixture of refractory and low-melting components with a binder was obtained in the laboratory. Low-temperature ceramics samples were synthesized. The structure of a separate layer of the sintered ceramics was examined by X-ray tomography. Experiments were conducted to confirm the reliability of the sintering simulation results obtained with taking into account the effect of the heterogeneous component distribution and fractional composition of the initial mixture on the properties of low-temperature ceramics.

Conjugates of 17α-substituted testosterone (1 and 2) and 17β-substituted epitestosterone (3 and 4) with pyropheophorbide a were synthesized. The scheme consisted of synthesis of 17α-hydroxy-3-oxopregn-4-en-21-oic and 17β-hydroxy-3-oxopregn-4-en-21-oic acids, and their coupling with pyropheophorbide a by means of either ethylene diamine, or 1,5-diamino pentane linkers. Mutual influence of steroidal and macrocyclic fragments in conjugates molecules was dependent on configuration of C17 and length of linker, that was established by analysis of 1H NMR spectra and molecular models of conjugates. Studies of interaction of conjugates with prostate carcinoma cells revealed that their uptake and internalization were independent on the androgen receptor activity, but dependent on the structure of conjugates, decreasing in the following row: 3 > 4 ≥ 1 > 2. Conjugates significantly decreased the LNCaP and PC-3 cells growth at 96 h incubation. Epitestosterone derivatives 3 and 4 also showed superior anti-proliferative activity versus testosterone ones. Conformationally more rigid conjugates 1 and 3, comprising short linkers, were more active than those with long linkers; conjugate 3 was the most potent.

Diethylene glycol dimethyl ether (diglyme) is interesting as a representative of ethers with several oxygen bridges in the molecule and as a model alternative fuel. A comparative study of the diglyme radiolysis at room temperature and at the boiling point was carried out. Boiling facilitates the cleavage of internal C‒O bonds, weakens the cage effect and diglyme regeneration processes, and also favors radical exchange and dimerization reactions. Unlike radiolysis at room temperature, irradiation at the boiling point generates four times less unsaturated fragmentation products and practically does not give disproportionation products of heavy radicals. The yield of radiolytic decomposition of boiling diglyme reaches 15.5 molecules/100 eV, which is almost 1.5 times higher than at room temperature.

The structure of the surface layer of a heterogeneous solid body (xenolite) before and after friction is studied by infrared and Raman spectroscopy. Before friction, the layer contained hornblende and pyroxene crystals. The friction resulted in partial transformation of pyroxenes into hornblende and the latter was transformed into montmorillonite clay. The xenolite surface is covered with a ~60-nm-thick layer of water.

The article presents a complex of laboratory core analyses conducted at the Center for Petrophysical and Geomechanical Research, Schmidt Institute of Physics of the Earth, Russian Academy of Sciences (CPGR IPE RAS). The complex provides for multiscale studies of the elastic properties, microstructure, composition, and porosity and permeability properties of rocks. The laboratory studies determine the dynamic and static elastic moduli, rock strength and creep parameters, and acoustic emission characteristics; 2D and 3D microstructure analysis is also performed. Dynamic elastic moduli are determined both under normal and reservoir-simulating conditions. Under normal conditions, multilevel ultrasound examination of samples is carried out; its results, together with those of microstructure analysis, are then used to determine the degree of inhomogeneity of the elastic properties of a sample, to reveal the anisotropy of these properties, and to compare the elastic properties of rocks at different scales. The results of geomechanical rock tests are necessary for constructing geomechanical models of reservoirs. The elastic parameters determined under normal and reservoir conditions are the basis for constructing correlation dependences that allow the geomechanical properties and principal stresses under reservoir conditions to be forecasted from well log data. Data on the elastic properties and microstructure of samples are used to construct different-scale models of the elastic properties of rocks under normal and reservoir conditions using petrophysical methods; these models further serve as a basis for petroelastic modeling of hydrocarbon fields and for predicting the viscoelastic behavior of rocks.

Thermal radiolysis under the conditions of electron-beam distillation at a dose to 240 kGy converts petroleum sludge into C4–C31 hydrocarbons with a yield to 80 wt %. The condensate distilled off contains about 20 wt % alkenes, thereby indicating the chain regeneration and thermal fragmentation of bulky alkyl radicals. The yield of the condensate increases to 90 wt % in the case of mixing the initial petroleum sludge with lignin. In this case, the yield of alkenes is lower due to the binding of unsaturated compounds by the components of charcoal and tar and because of a change in the mechanism of alkane fragmentation in the presence of lignin.

The materials on litho- and biostratigraphy (collared lemming, Dicrostonyx) of the Middle Neopleistocene of the northeast Russia were revised and litho- and biostratigraphic methods were mutually tested for determination of the age of geological bodies. The reasonable stratigraphic division and correlation of the Neopleistocene are especially topical because of the current preparation of a new common stratigraphic chart of Quaternary sediments. The petrographic composition of the coarse-clastic material and the orientation of clasts in moraines are regionally consistent lithostratigraphic criteria. In the Pechora (Dnieper) moraine, the elongated rock clasts are oriented in a sector of 20°–60° in contrast to an azimuth of 270°–360° of the Vychegda (Moscow) moraine, which, in addition to petrographic composition of rocks, indicates the contribution of terrigenous material from different glacial provenances during formation of moraines. Certain differences were revealed also in assemblages of heavy minerals. The Middle Neopleistocene rodent fauna was found between the Pechora and Vychegda moraines. The stratigraphic position of microtheriofauna is identified on the basis of evolution level of molars of collared lemmings. By proportion of simplicior and henseli morphotypes for M1 and M2, all fossils belong to three groups corresponding to three evolution stages of a tooth system: Late Pechora (Late Dnieper, MIS 8), Rodionovo (Shklov, MIS 7), and Early Vychegda (Early Moscow, MIS 6). They include D. simplicior morph 2 (Gavrilovka, Bol’shaya Sluda, Akis’, Laya-4 localities), D. simplicior morph 3 (Sercheiyu-1, Laya-3 localities), and D. ex gr. simplicior—gulielmi (Shapkina-4, Chuley, lower horizon of Kipievo localities) morphs. These evolution stages correspond to Late Pechora (Late Dnieper, MIS 8), Rodionovo (Shklov, MIS 7), and Early Vychegda (Early Moscow, MIS 6) intervals. Taking into account the paleoclimate data, the presence of the lemmings in the region during the Rodionovo time is rather plausible.

This paper presents the results of numerical experiments on the impact of electromagnetic radiation on strength characteristics of natural and artificial materials and the data of laboratory experiments on the destruction of Berea sandstones and concretes under the impact of an electric current on loaded samples with a constant velocity of deformation.

The pyrogenic conversion of lignin to a phenolic tar can be significantly enhanced by combining dry distillation with simultaneous electron-beam treatment of lignin. The tar produced by the combined method contains three times more benzenediols in comparison with conventional pyrogenic distillation method. As shown, the tar of radiation-thermal origin can inhibit the thermopolymerization of certain monomers, such as styrene. The inhibiting ability of tar exceeds that of synthetic phenolic inhibitors. In the presence of 0.025 wt% of the tar, the induction period of styrene thermopolymerization at 120 °С is at least 120 min. Radiation-thermal formation of phenolic tar obeys the chain mechanism and thereby, is a highly efficient process.

The radiolysis of diethylene glycol dimethyl ether (diglyme) in a boiling state has been studied for the first time. Boiling facilitates the cleavage of internal C–O bonds, weakens the cage effect and diglyme regeneration processes, and facilitates the exchange and dimerization reactions of radicals. As compared with radiolysis at room temperature, the amount of unsaturated products of diglyme fragmentation formed during irradiation in the boiling state is smaller by a factor of 4, and the disproportionation products of heavy radicals are found in negligible amounts, if any. The yield of radiolytic decomposition of diglyme under boiling conditions is ∼15 molecule/100 eV, which is higher than that at room temperature by a factor of almost 1.5.