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A method is proposed for determining the power of the built-in heater in welding polyethylene pipe at low ambient temperatures; this approach is based on solving the inverse control problem. In determining the heater power, weighting factors and temperature specifications may be selected so that the dynamics of the final welding boundary within the thermal influence zone corresponds to normal welding. [ABSTRACT FROM AUTHOR]

The reaction of 3,4-dihydro-2H-thiopyrane-1,1-dioxide and 3,4,6-triphenyl-3,4-dihydro-2H-thiopyrane-1,1-dioxide alkylation is studied by a DFT quantum chemical simulation using the REVPBE0 functional. Geometric parameters of initial compounds, products, transition states, and Gibbs free energies of activation are calculated. The influence of the steric factor on the reaction regioselectivity is demonstrated. [ABSTRACT FROM AUTHOR]

The surface of monocrystalline silicon irradiated with a high-power pulsed beam of carbon ions and protons is studied using optical and scanning electron microscopy. The surface is irradiated using a TEMP-2 accelerator in a vacuum of ~10–3 Pa. The ion beam consists of 70% carbon ions (C+ + C+2) and 30% protons. The sample is irradiated with one pulse with a dose of 1.5 × 1013 ions/cm2. Craters characterized by a hexagonal shape are obtained on the silicon surface. X-ray diffraction analysis shows the presence of carbon content inside the crater. [ABSTRACT FROM AUTHOR]

An analysis of the results of time-resolved transient S1→Sn absorption spectroscopy studies and quantum chemical calculations of the dye (2E,5E)-2,5-bis[4-(1,4,7,10,13-pentaoxa-16-azacyclooctadecane-16-yl)benzylidene]cyclopentanone (1) and its metal complexes confirm the generality of the phenomenon of photoinduced recoordination of metal cations in the complexes of bis(aza-18-crown-6)-containing derivatives of the dibenzylidenecyclobutanone (dibenzylidenecyclopentanone) series. The results obtained confirmed the existence of the first stage of photoinduced recoordination of metal cations in the 1 • (Mn+)2 (M = Ba2+, Ca2+, K+) complexes which completes within a few hundreds of femtoseconds. The process involves cleavage of the N—M bond followed by displacement of the metal cation from its equilibrium position in the azacrown ether cavity and by transformation of the "axial" conformation of the complex to "equatorial" one. It was demonstrated that the barrier photoinduced recoordination of the cation in the 1 • (Ba2+)2 complex is accompanied by the change of the type of the solvation shell of the crowned Ba2+ cation in the following order: (2+1)MeCN, (3+1)MeCN, 4MeCN. In a low-temperature butyronitrile glassy matrix at 77 K, the photoinduced recoordination is completely suppressed. The Mg2+, Li+, and Na+ cations can form not only the inclusion complexes, but also the 1: 3 complexes ((Mn+) • 1 • (Mn+)2) of moderate stability through additional coordination to the carbonyl group of the dye. The radii, rS, of solvates of different-stoichiometry complexes containing the same metal cation determined from the data of anisotropy decay kinetics of S1→Sn absorption are about 9.2 Å for 1 • (Mg2+)2 and nearly 11.5 Å for Mg2+ • 1 • (Mg2+)2. [ABSTRACT FROM AUTHOR]

Information about the Nizhny Novgorod scientific and pedagogical school Optimization in Automation Systems for Design and Control is presented. The founder of the school is Honored Scientist of the Russian Federation, Professor Dmitrii Ivanovich Batishchev. [ABSTRACT FROM AUTHOR]

The results of studying the effect of temperature and magnetic field on the relaxation of the thermo-optical signal in semiconductor samples of n-Ge, n-InSb, and ZnSe:Ni with different electronic spectra are presented. The results were obtained using a two-beam fiber-optic "pump–probe" method with a Fabry–Perot interferometer in the temperature range from 4.2 to 300 K with the application of a magnetic field up to 8 T. [ABSTRACT FROM AUTHOR]

The effect of quantum corrections to the energy distribution function of light particles, which are associated with quantum indeterminacy due to their frequent collisions with heavy buffer gas particles, is investigated theoretically for CO molecules and He atoms as an example. We analyze the effect of quantum corrections to relaxation rate constants of vibrationally excited CO molecules on helium atoms depending on the gas mixture composition and the gas density and pressure. The effect of quantum corrections on the vibrational relaxation time is calculated using the model of level-by-level vibrational kinetics. The propositions concerning the experimental verification of this new effect that has been predicted theoretically are formulated. [ABSTRACT FROM AUTHOR]

The supramolecular complex formation between donor (E)-bis(18-crown-6)azobenzene ((E)-1) and bis(ammoniopropyl) derivatives of bipyridine and dipyridylethylene acceptors (2, (E)-3) was studied in MeCN using steady-state absorption and fluorescence spectroscopy, fluorescence kinetics, and quantum-chemical (DFT, TDDFT, QDPT) calculations. The complexes are quite stable, but they undergo decomposition via substitution by alkali and alkaline-earth metal cations. The formation of 1:1 and 1:2 complexes between (E)-1 and alkali and alkaline-earth metal cations (Mn+) was confirmed. Spectral-kinetic parameters and stability constants were calculated. The determined stability constants are generally lower than those for bis(crown)stilbene complexes due to moderate electron-donor ability of azobenzene. The plot of fluorescence quantum yields of 1·(Mn+)2vs charge density of the metal cation shows two separate linear relations for unipositive and dipositive ions. The results of quantum-chemical calculations supported the conclusions derived from steady-state experiments. The most stable conformations of pseudocyclic complex (E)-1·2 and two metal complexes were found. The latter involve 4 or 6 molecules of acetonitrile per each complex: (E)-1·(Ca2+)2·(MeCN)4, (E)-1·(K+)2·(MeCN)6. Based upon quantum-chemical calculations of model species, the character of absorption bands of crowns and their complexes with actual energy conversion pathway are discussed. [ABSTRACT FROM AUTHOR]

For thermal diagnostics of friction determining the time dependence of frictional heat generation and, accordingly, the moment of friction in self-lubricating sliding bearings using temperature data, an algorithm for solving the inverse problem of heat conduction by iterative regularization is proposed. The iterative regularization algorithm for restoring the frictional heat generation function from temperature data using a three-dimensional model of the thermal process and taking into account the speed of the swinging movement of the shaft is implemented. An assumption was made about the uniform distribution of specific heat generation along the length of the bearing to simplify the formulation of the problem. The numerical solution of the model problem was carried out with the shaft oscillating with a frequency of 1 Hz and amplitude of 7.5°. The time step was chosen from the Courant condition and was 0.1 s. The full-time interval was divided into local ones when solving the inverse problem in order to avoid storing large arrays of temperature data at each iteration. The solutions at the junctions of local intervals were glued. A condition for stopping the iterative process of restoring the frictional heat generation function is proposed, taking into account the total error in temperature measurements and calculations using local intervals. Calculations show that the accuracy of restoring the function of the specific intensity of frictional heat generation using the developed algorithm for solving the inverse problem of 9.9% is commensurate with the accuracy of 3.8% of specifying temperature information. The developed algorithm for determining frictional heat generation using a 3D model of the thermal process can be used to determine the friction torque from temperature data in real self-lubricating sliding bearings operating in the oscillation mode. [ABSTRACT FROM AUTHOR]

This article studies the influence of plastic deformation, thermal treatment, and electron irradiation on the structural-phase state of Cu–40 at % Pd. Initial specimens, specimens obtained by rolling to 0.2 mm, specimens annealed after rolling in an argon environment at 950°C for 1 h, and specimens irradiated with high energy electrons in air at 300°C were exposed to X-ray diffraction analysis. The phase composition of the specimens changed after rolling: about ~6% of the ordered β phase with BCC structure was formed, which disappeared after annealing. As a consequence of irradiation, a layer of copper oxide CuO was formed on the alloy surface, which under normal thermal conditions was formed at 400–500°C; in addition, the reflections of the ordered β phase in the near surface layers disappeared. The elemental composition of the alloy changed over depth starting from the irradiated metal surface. Phases with a low extent of long range order and higher palladium content were formed. The existence of these phases was due mainly to selective oxidation of copper. [ABSTRACT FROM AUTHOR]

The altered rocks of the Kyzyk-Chadr deposit are mostly composed of quartz and dioctahedral K‑micas of the muscovite–phengite series, which are dominant in almost in all zones of a metasomatic aureole. The assemblages of albite with chlorite and epidote are typical only of the peripheral parts of this aureole characterized by propylitic alteration. The central and deep areas of the aureole exhibit quartz–feldspar alteration. To reveal the hidden mineralogical zonation of the deposit, we studied the petrography of metasomatites and used the results of X-ray diffractometry (XRD) and IR spectroscopy of micas from the mineralized quartz–sericite metasomatites. The elements of hidden mineralogical zonation, which depends on the variations in the amount of phengite and muscovite of light mica metasomatites, are identified on the basis of XRD and IR spectroscopy. Phengite is a dominant component of the central and deep parts of the ore-metasomatic aureole of the deposit, whereas the amount of the muscovite component gradually increases toward the flanks and the upper parts. This trend is correlated with a general direction of mineralogical ore-metasomatic zonation and can probably be explained by the change in P-T conditions in a volume of a porphyry copper ore-magmatic center. The phengite/muscovite ratio (an indicator of hidden mineralogical zonation) can be used for searching for and estimation of porphyry copper deposits as an objective criterion during the correlation between known and forecasted ore bodies. [ABSTRACT FROM AUTHOR]

An experimental cell design and an optoelectronic unit have been developed for studying relaxation processes in the near-surface region of semiconductors under pulsed laser irradiation in a temperature range from 3 to 300 K and a magnetic field up to 12 T. [ABSTRACT FROM AUTHOR]

This study analyzes the thermal process in a radial slide bearing made of filled PTFE and used in the reciprocal movement mode. The thermal process in the bearing is described by a three-dimensional heat conduction equation in cylindrical coordinates. The influence of the swinging movement of the shaft on the nonstationary 3D temperature field was considered by the convective term of the heat equation. A simple record of the condition of frictional heat generation in the contact zone is proposed on the assumption that the bearing has a small eccentricity. To determine the nonstationary temperature field in the sliding bearing, the well-known finite difference method (FDM) was used: the FDM includes splitting by spatial variables and consists in solving unidimensional difference equations step by step. A monotonous difference scheme was used to solve the unidimensional equation against the angular coordinate with a convective term that considered the swinging movement of the shaft. The monotonous scheme allows solving the heat equation at any step in the time and angular variables. The solution proposed for choosing from the multitude of such approximate solutions is the solution with the Courant number equal to 1. An example of calculating the thermal process of the sliding bearing made of F4C20 with the following geometric dimensions is considered: a shaft radius of 0.0125, bushing radii of 0.013 and 0.016, and shaft and bearing lengths of 0.096 and 0.022 m. The computational experiments are carried out at an equal load of 2400 N and different amplitudes and frequency of oscillations. At a frequency of 1 Hz and shaft movement amplitude of 60°, periodic temperature fluctuations at an amplitude of approximately 2.5°C are noted over time. As indicated by calculations with varying heat capacity at the convective term, the temperature fluctuations are caused by the movement of the shaft. The developed calculation methods can be used as a technique for determining the kinematic conditions in which it is necessary to consider the speed of the shaft in the mathematical model of the thermal process. The results can be used in thermal friction diagnostics in real slide bearings. [ABSTRACT FROM AUTHOR]

The problem of implicit expressibility in many-valued logics is considered. Necessary and sufficient conditions for a class of autodual functions to be implicitly maximal are obtained. [ABSTRACT FROM AUTHOR]

Understanding the processes of perovskite crystallization is essential for improving the properties of organic solar cells. In situ real-time grazing-incidence X-ray diffraction (GIXD) is a key technique for this task, but it produces large amounts of data, frequently exceeding the capabilities of traditional data processing methods. We propose an automated pipeline for the analysis of GIXD images, based on the Faster Region-based Convolutional Network architecture for object detection, modified to conform to the specifics of the scattering data. The model exhibits high accuracy in detecting diffraction features on noisy patterns with various experimental artifacts. We demonstrate our method on real-time tracking of organic-inorganic perovskite structure crystallization and test it on two applications: 1. the automated phase identification and unit-cell determination of two coexisting phases of Ruddlesden–Popper 2D perovskites, and 2. the fast tracking of MAPbI3 perovskite formation. By design, our approach is equally suitable for other crystalline thin-film materials. [ABSTRACT FROM AUTHOR]

It is shown by computer modeling that at feed pipe and top drain pipe diameters to cylindrical hydrocyclone body part diameter ratio of 0.41 hydraulic losses are minimized if volume flow rates of the suspension separated in the hydrocyclones are equal. Hydrocyclone designing with appropriate ratios of the geometric parameters makes it possible to reduce their overall dimensions without decrease of the prescribed separation factors and volume throughput, but with some increase of power consumption. Equations are derived for calculating volume throughput and separation boundary grain of hydrocyclones with geometric and operating parameters varying in a wide range. [ABSTRACT FROM AUTHOR]

The effect of pulsed ion-plasma irradiation in the Plasma Focus Vikhr setup and irradiation with 20-MeV electrons at the Microtron-ST accelerator on the mechanical properties of the Inconel 718 precipitation-hardened alloy obtained by the selective laser fusion method has been studied. It was found that ion-plasma and electron irradiation does not affect the properties of the alloy, which is explained by the small thickness of the modified layer during irradiation at the Plasma Focus setup and insufficiently high electron fluence for the manifestation of radiation-stimulated process of redistribution and dissolution of dispersed precipitates of the strengthening phases. The results obtained bear evidence of a high resistance to crack propagation and the absence of a tendency of the studied alloy to embrittlement. [ABSTRACT FROM AUTHOR]

Background: While no "gold-standard" pharmacotherapy for nonalcoholic fatty liver disease (NAFLD) is yet established, essential phospholipids (EPLs) are reported to decrease steatosis and improve laboratory parameters. Objective: This analysis evaluated adherence and satisfaction with EPL treatment as patient-reported outcomes and their relationship with changes in laboratory and ultrasound parameters among Russian patients with NAFLD. Methods: Data were pooled from three observational Russian studies—MANPOWER (2015–2016), LIDER 1 (2012–2013), and LIDER 2 (2013)—in which EPLs were used for at least 12 weeks in the treatment of liver diseases and which measured both subjective and objective endpoints. Only patients who had NAFLD were included in this analysis. The main endpoints were to determine treatment adherence and satisfaction with 12 weeks of EPL therapy, relationship between adherence/satisfaction and changes in the laboratory and ultrasound parameters. A secondary subgroup analysis was performed to identify patients with NAFLD who responded better (or worse) to 24 weeks of adjunctive EPL treatment. Results: Overall, 3384 patients were included. A total of 82.2% of patients were adherent to 12 weeks of EPL treatment; high/very high satisfaction was reported by 15.3%/65.9% of clinicians and 15.9%/64.4% of patients. There was positive correlation between patients' adherence and satisfaction and significant improvement in laboratory (transaminases, lipid profile; p < 0.001) and ultrasound (steatosis, p < 0.001) parameters, and improvement in symptoms (p < 0.001) after 24 weeks of EPL. Male patients, patients with unhealthy lifestyles, and those with more comorbidities showed a better response in laboratory and ultrasound parameters. Conclusions: Patients with NAFLD treated with adjunctive EPL therapy in real-world clinical practice in Russia showed good treatment adherence and treatment satisfaction. Improvements in laboratory and ultrasound parameters, as well as dynamics of patient symptoms, were positively correlated with adherence and satisfaction. Plain Language Summary: Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver disease, and patients have a risk of liver cancer and needing transplantation. Patients with advanced NAFLD are usually recommended to use medication. Clinical trials in patients with NAFLD showed that essential phospholipids (EPLs) comprising phosphatidylcholine improved liver fat accumulation (known as steatosis), so treatment guidelines in several countries recommend they be added to the usual therapy. EPLs have been associated with both objective and subjective improvements. This real-world study evaluated three observational studies to assess how patient adherence and satisfaction with EPL treatment were related to changes in clinical parameters in 3384 Russian patients with NAFLD. Overall, 82.2% of patients were adherent with 12 weeks of EPL therapy, and almost two-thirds of patients (64.4%) and clinicians (65.9%) reported very high satisfaction with treatment. Patients' adherence and satisfaction increased alongside significant improvements in liver enzymes, lipid levels, liver fat content (steatosis), and fewer symptoms after 24 weeks of EPL therapy. Male patients, those with an unhealthy lifestyle, and those with other comorbid conditions had the best response to EPL therapy. This study shows that Russian patients with NAFLD have good adherence and satisfaction with EPL therapy in routine clinical practice and highlights the importance of adherence to EPL therapy in these patients. [ABSTRACT FROM AUTHOR]

We performed a comparative analysis of the pharmacological activity of the hybrid organotin compound bis(3,5-di-tert-butyl-4-hydroxyphenylthiolate)dimethylol (Me-3) administered in different modes to mice with transplanted melanoma B16 to identify the most effective dosage regimen. Three modes of administration were used: preventive (before transplantation of tumor cells), classical according to Z. P. Sof'ina (48 h after transplantation of tumor cells), and delayed (7 days after transplantation of tumor cells, after formation of nodules of the primary tumor node). Compound Me-3 was administered at a total dose of 375 mg/kg intraperitoneally once a day for 5 days. The classical mode of administration was identified as the most effective, which indicates the preventive antimetastatic activity of Me-3 on the model of the transplanted mouse tumor melanoma B16. [ABSTRACT FROM AUTHOR]

Data on geology of bauxite deposits associated with rich iron ores of the weathering crust of Precambrian ferruginous-siliceous shale formation within the Kursk Magnetic Anomaly (KMA) are summarized. High -grade iron ores and bauxites occur under a predominantly Paleozoic sedimentary cover at depths of over 400 m. The main potential of iron–aluminum raw materials in the region is concentrated in Bolshetroitskoe, Vislovskoe, Olimpiyskoye and Melikhovo-Shebekinskoe deposits. Bauxite and ferralite deposits were formed during pre-Visean time after phyllitic shales of Yakovlev and Korobkovsky Formations. They consist mainly of boehmite with hematite impregnation, often with a significant admixture of kaolinite and chlorite. Average content (%) is usually Al2O3 ~50.1, SiO2 ~6.0, Fetot. ~14.0. The total bauxite potential of KMA is 1201.7 mln t (P1 + C1 + C2 + B). Subsurface mining even with small projected capacity of 1.0–2.5 mln t/year would cover the deficit of alumina presently covered through import. [ABSTRACT FROM AUTHOR]

Omniphobic and icephobic twin-scale surfaces based on the "urchin"-like fluorinated Al2O3 particles are presented. Combined effect of hierarchical topography and fluorination supplied to the surfaces omniphobic and icephobic properties. The study of the stability of the Cassie wetting state is reported. High apparent contact angles were accompanied with the low contact angle hysteresis and high stability of the Cassie air trapping wetting state. Time delay of the ice crystallization as high as 88 ± 5 min was established when compared to the ice formation on flat aluminum and non-fluorinated "urchin"-like surfaces. Crystallized water droplets formed on the reported nano-structured surfaces were easily blown out by the air jet with the velocity of v = 3.0 ± 1.0 m/s, (which is markedly lower than that common for exploitation of aircrafts and turbines). Heated "urchin"-like surfaces completely restored their omniphobic and icephobic surfaces after thawing. Qualitative analysis of water freezing is supplied. [ABSTRACT FROM AUTHOR]

This study was aimed to assess the effectiveness of magnesium (Mg)-vitamin B 6 replenishment and its correlation with clinical status in pregnant women (PW), and quality of life in women with hormone-related conditions (HRCW) and hypomagnesemia (HME). Data collected in four observational studies were pooled and analysed. All women received Mg supplementation for 4 weeks. The proportion of women with normalized Mg level, and the correlation between serum Mg dynamics and number of symptoms/complaints (PW) or changes in World Health Organization quality of life questionnaire scores (WHOQOL; HRCW) were evaluated. 869 PW and 957 HRCW were included in the study. Normalization of serum Mg level to ≥ 0.66 mmol/L occurred in 92.1% of PW and 78.4% of HRCW, and to ≥ 0.8 mmol/L in 73.8% and 58.9%, respectively. Mg normalization was accompanied by a median decrease of 1 symptom and 1 complaint in PW. Serum Mg level increase by 0.1 mmol/L was associated to significant changes in the WHOQOL scores in HRCW. Treatment of HME with the Mg for approximately 4 weeks provided a high response rate of Mg serum level, was associated with an improvement in symptom severity and complaints in PW, and WHOQOL score in HRCW. A 0.8 mmol/L cut-off appeared to be more relevant in terms of patient-reported outcomes. [ABSTRACT FROM AUTHOR]

In experiments on the controlled pulsed heating of a substance, the heat transfer to aqueous glycols and propylene glycols solutions was compared in the full range of compositions. The research was conducted in the field of stable and superheated states. The used mode involved the thermostabilization of a probe heater when a specified temperature was reached. The typical heating duration was 10 ms. The general feasibility of the measurement of primary quantities in aqueous solutions superheated with respect to the liquid–vapor equilibrium temperature is shown. In test experiments with an aqueous solution of PPG-425 polypropylene glycol, the measurements were carried out with short-term superheating relative to the liquid–liquid equilibrium temperature, as well as in a certain range of compositions relative to the temperature of the diffusion spinodal of the solution. [ABSTRACT FROM AUTHOR]

Lead sulfide (PbS) thin films of different morphology were synthesized via direct interaction of lead and sulfur vapors. Low temperature nonequilibrium RF (40.68 MHz) plasma discharge at low pressure ((3–5) × 10–3 Torr) was used for the initiation of chemical interaction between precursors in the gas phase. The in-situ Optical Emission Spectroscopy (OES) was utilized to determine the exited reactive species existing in plasma discharge and possible mechanism of plasma-chemical reactions resulting in the formation of the solid phase. The chemical composition, structure and morphology of the surface of the as-deposited materials in dependence of parameters of the plasma process such as stoichiometry of the precursors in the gas phase, power of the plasma discharge and substrate temperature were characterized by SEM, XRD and AFM analytical techniques. The optical properties and electrophysical parameters of the samples were studied as well. [ABSTRACT FROM AUTHOR]

Miniature fiber optic sensors were used for detection of initial boiling-up of uniformly superheated liquid in the capillary of a bubble chamber. The possibility of local boiling-up activation by a laser pulse at a single-mode fiber end with a diameter of 9 m was shown. The object of the study was -pentane superheated at 82 K with respect to the liquid-vapor equilibrium temperature at atmospheric pressure. The control sensor recorded a signal similar to that of spontaneous macroscopic boiling-up. The activation threshold value for the radiation intensity at the end of the fiber was found. This value varies for different fibers. The minimum pulse energy required for activation was 6 nJ, which was insufficient for triggering of the thermal activation mechanism. An assumption is made about the mechanical effect of laser pulse on the fiber-liquid interface. [ABSTRACT FROM AUTHOR]

With the global warming, the frequent and severe river floods in Arctic regions have affected the distribution of willows in river lowlands. To investigate the effect of floods, especially waterlogging, on nitrogen conditions for willows, we measured their foliar nitrogen content and isotopic composition (δ15N), under various hydrological conditions in Northeastern Siberia, which was classified into four conditions according to the previous study: dry, wet, waterlogging [WL], long-period waterlogging [LWL] respects to willows' physiological response. The δ15N values of willow leaves, which correlate to those of the soil, were significantly lower under dry (−3.6 ± 1.3‰) and wet (−3.5 ± 1.7‰) than WL (0.3 ± 2.6‰) and LWL (2.7 ± 2.4‰), indicates acceleration of soil nitrogen dynamics for waterlogging. There is no higher foliar nitrogen contents found under LWL (2.3 ± 0.3%) than WL (2.4 ± 0.4%). This might be caused by little decreased nitrogen uptake related to the low activity of carbon fixation in willows under LWL. Interestingly, LWL occurred over a wide area following extreme flooding in 2017; yet, willows survived, whereas potential competing species (larch) died. We further predict that the distribution of willows in Arctic riparian areas will expand, particularly after extreme floods under Arctic amplification. [ABSTRACT FROM AUTHOR]

The promising fields of gallium oxide application are the production of hybrid cars, electrical equipment of high-power, ultraviolet radiation sensors and uninterruptible power supplies. However, the main factor hindering its massive commercial use is the lack of synthesis technologies, that should be cheap, reproducible, and scalable. In this work we develop a novel plasma-chemical method of Ga2O3 synthesis. The high-purity elemental gallium was used as the precursor, which was delivered by argon flow to the reaction zone, where the interaction with iodide pentoxide took place. RF (40.68 MHz) non-equilibrium plasma discharge at low pressure (0.1 Torr) was employed for the initiation of interactions between precursors. Optical Emission Spectroscopy in tandem with quantum-chemical calculations allowed us to find out the reactive species formed in the plasma discharge. The properties of the solid phase obtained were studied as well. [ABSTRACT FROM AUTHOR]

Introduction: The current non-invasive tools for the diagnosis of non-alcoholic fatty liver disease (NAFLD) have methodological limitations. We aimed to develop a non-invasive scale to assist in the diagnosis of NAFLD. To achieve our aim, we conducted a secondary analysis of data from a large observational study conducted in Russia. Methods: This retrospective analysis assessed the frequency of NAFLD in the population of patients in the DIREG_L_06725 study, an epidemiological, observational, cross-sectional, multicenter study performed in 50,145 outpatients from 16 Russian cities. Among the cohort of patients diagnosed with NAFLD, we identified factors associated with the risk of NAFLD. To develop a non-invasive tool for diagnosing NAFLD, we also determined the frequency of steatohepatitis. Results: Our analysis included 48,297 patients; NAFLD was present in 20,281 patients (42.0%). The majority (64.1%) were women (80.3% post-menopause), and 87% had a body mass index (BMI) > 27.0 kg/m2. We developed a fully non-invasive scale (St-index) that showed a specificity of 91.4% for ruling in steatosis, and a sensitivity of 93.8% for ruling out steatosis. Multivariate regression analyses conducted in the subgroups of patients aged ≥ 12 and < 18 years and those with BMI < 25.0 kg/m2 produced area under the receiver operating characteristic (AUROC) curve values of 0.8243 and 0.7054, respectively. The factors most strongly associated with the development of NAFLD were age > 35 years, presence of type 2 diabetes mellitus, and a waist circumference/height ratio > 0.54. Conclusion: Our non-invasive steatosis scale, St-index, can help physicians diagnose NAFLD in high-risk patients in the absence of ultrasound data. [ABSTRACT FROM AUTHOR]

Spectral, luminescent, and time-resolved properties of 2,4-dibenzylidenecyclobutanone and its diethylamino, methylthio, methoxy, and dimethoxy derivatives have been studied. The electron-donating substituents shift bathochromically the absorption band maximum by 45–140 nm relative to unsubstituted dienones and the fluorescence maximum by 50–125 nm relative to the methoxy derivative. Upon the laser pulse, dienones convert to the triplet state with a lifetime of 0.15–3.5 μs and a stable photoproduct is formed. [ABSTRACT FROM AUTHOR]

The possibility of local activation of liquid boiling-up by a laser pulse at the end of a single-mode light guide is shown on the example of n-pentane superheated at 81°C relative to the liquid–vapor equilibrium temperature. An activation threshold is detected for the radiation intensity at the end of the light guide. Its value depends on the state of the light guide end, and the boiling processes are likely to develop at the interface. As with the random boiling-up process, upon activation, a stepwise propagating change in the refractive index of the liquid is observed. A conclusion is drawn on the uniformity of the recorded processes during random and activated boiling-up of n-pentane. [ABSTRACT FROM AUTHOR]

To assess the efficiency of the method of thermal diagnostics of friction in a system of sliding bearings at shaft speeds of no more than 2π rad/s, friction torque values obtained by solving an inverse heat-transfer problem and measuring with a commercial friction machine sensor have been compared. It has been established that the agreement between the total friction torque values obtained using fundamentally different methods is within 10–15%. The ability of the thermal diagnostics method to identify differing friction torques in each bearing is substantiated by the recovery of their identical values under conditions of difference of the temperature fields in the bearings. [ABSTRACT FROM AUTHOR]

The method of registration of free neutrons in a complex with geoelectrochemical methods has been applied for the first time to a case study in the Arkhangelsk diamondiferous province. Its application is based on the newly developed concept about formation of diamonds in the deep chamber, shielded by dense rocks. The high density of energy in such an excited environment leads to dissociation of nuclei, cluster radioactive decay, and low-energy transmutation of elements. The cluster radioactive decay and the low-energy transmutation of nuclei that occur during the formation of a kimberlite pipe produce electromagnetic radiation with a quantum energy of tens and hundreds of keV. This concept was confirmed by research and development on the reference Pionerskaya and Verkhnetovskaya pipes; an exploration technique based on this geological model is proposed. [ABSTRACT FROM AUTHOR]

In this work, results of numerical simulation of the interaction of pulsed capillary discharge plasma jets at atmospheric pressure are presented. The interaction of the pulsed plasma jets with a shock wave is considered. Modes with plasma jets created by the capillary discharge with a vaporizing wall expiring through a magnetic nozzle are simulated. Results obtained for several plasma channels are presented together with calculated plasma jets in the capillary discharge with a vaporizing wall. [ABSTRACT FROM AUTHOR]

The electrostatic interaction between charged particles in a dusty plasma has been studied using the Ornstein—Zernike integral equation for a multicomponent plasma. The transition to the one-component approximation has been performed for the nonideal plasma subsystem. It has been shown that the interaction between charged plasma particles at the coupling parameter Γ of the dust subsystem less than unity is well described by the Debye potential with the complete screening constant. The static dielectric function in the region of low wavenumbers becomes negative at Γ > 1 and this region expands with increasing Γ. As a result, attraction between likely charged particles and repulsion between oppositely charged ones occur in a certain distance range. In this case, the total pressure, specific heat at constant volume, and isothermal compressibility of the dusty plasma remain positive in the entire studied range of the nonideality parameter Γ < 250, but the isothermal compressibility of only the dust nonideal subsystem becomes negative at Γ ≈ 2. [ABSTRACT FROM AUTHOR]

The neutron generation by hot, dense, and fast Z- and Θ-pinch plasma with the parameters achievable at the present development stage of high-power pulsed technology has been calculated. It has been proposed to use a hot plasma with a high density of 1017 cm−3 as an initial state for subsequent compression by Z- and Θ-pinches to achieve the conditions necessary for fusion reactions. Such plasma can be obtained using high-power pulsed plasma accelerators. [ABSTRACT FROM AUTHOR]

We present the experimental results for the temperature dependences of the thermal diffusivity, resistivity, and thermoEMF of six iron-titanium binary-system alloys with a Ti content of up to 3 at % at high temperatures. The existence of the γ domain and, thus, presence of the α → γ and the γ → α structural phase transitions are clearly recorded in the thermal diffusivity polytherms. The Curie temperature, which is determined from the position of the λ minimum of thermal diffusivity, does not depend on the titanium concentration within the experimental accuracy. [ABSTRACT FROM AUTHOR]

Abstract—The electrical conductivity, thermo-emf, and elasticity coefficient were experimentally studied in multilayered carbon nanotubes (CNTs) exposed to room-temperature irradiation. The initial CNTs with dimensions of 18 ± 7 nm were obtained via chemical vapor deposition using propane–butane as precursor. The irradiation of CNTs was implemented on Mikrotron-ST cyclic electron accelerator at the energy of 21 MeV and electron doses of 0.3 × 1017, 0.7 ×1017, 1.1 ×1017, and 1.5 × 1017 cm–2. The characteristics of initial and irradiated samples were measured in a dielectric cylinder. The following critical parameters of dielectric–metal transition in CNTs were established: array density (ρ1), elastic strain of CNT (ρrel), maximum electrical conductivity (σmax), and elastic strain coefficient (ε). The irradiated CNTs exhibit a decrease in thermo-emf (Seebeck coefficient (α)) by 50% or more in comparison with the initial samples, which is due to the formation of radiation defects. [ABSTRACT FROM AUTHOR]

The stability of the system of sulphur hexafluoride dimer SF6 under the action of external laser radiation has been estimated using ab initio quantum-chemical calculations of the vibration–rotation spectrum of SF6 monomers as well as homo- and heterodimers. It is noted that for simple CO molecule as an example, the most widely used method of calculations based on the Hessian matrix approach cannot serve as a reliable instrument in quantitative calculations of some molecular systems. As a potential analog, we have tested the algorithm for obtaining the vibration–rotation spectrum based on molecular dynamics data. [ABSTRACT FROM AUTHOR]

Our goal is to find and apply simple methods for calculating the scattering cross sections of particles in a screened Coulomb potential in a wider range of wave vector magnitudes than is possible in the Born approximation. Using the technique of Meijer's G-function, we obtain expressions for the scattering amplitude and the quantum scattering cross section in the limit kd ≫ 1, where d is the screening radius and k is the wavenumber. We compare the analytic results with quantum computations of the elastic scattering process by expanding the solution in a power series of partial waves. We investigate the domain of wave vectors where the Born approximation is no longer applicable but the new approximation works. In this domain, the number of angular momenta that must be taken into account in summing the partial cross sections increases abruptly, and a more precise analytic approximation might therefore noticeably reduce the computational effort. We also show that calculations of the classical integrated scattering cross section must take into account that the finite screening length of an interaction potential causes a cross section to shift off the mass shell. Taking this shift into account allows obtaining a good coincidence of numerical and analytic data for the scattering cross section, including beyond the applicability limits of the Born approximation. [ABSTRACT FROM AUTHOR]

The analysis of the available data on the α + 9Be elastic scattering in the energy range from 28 to 104 MeV, including recent measurements at energies of 30, 40, and 90 MeV is carried out. The parameters of the semi-microscopic potential are obtained in the framework of the dispersion optical model, in which the exchange components of the average field potential were calculated using the previously proposed pseudo-oscillator approximation for the single-particle density matrix. The found potential is tested using the distorted wave method on the analysis of inelastic scattering in the considered energy region with excitation of the 5/2− (2.43 MeV) and 7/2− (6.38 MeV) levels of the ground-state rotational band. The potential parameters used for the output channel were estimated on the basis of the energy dependence. A satisfactory description of the angular distributions and the values of the deformation length is obtained. [ABSTRACT FROM AUTHOR]

A new concept of cluster evolutionary minerageny is based on the idea of the formation of the Earth from the primary stellar material, which was preserved in the planet's core. Its further destruction due to decay of heavy nuclear matter results in fragmentation of the material until the appearance of superheavy elements with their further nuclear dissociation. As a result, protomagma arises and penetrates to the upper mantle in the form of plume flows. This process supports the reactions that control the formation of chemical elements, minerals, ores, and rocks, which compose the upper mantle and the Earth's crust. The processes of nuclear dissociation lead to the release of energy and decompression of matter. This initiates an increase in the Earth's volume, its geotectonic activity, and the creation of the hydrosphere and atmosphere. [ABSTRACT FROM AUTHOR]

Abstract: The static properties of the Yukawa fluids are investigated in a wide range of parameters: the value of the effective nonideality parameter Γ* ranged from 0 to 155, and the value of the screening parameter κ ranged from 1 to 5. Investigations are carried out by the Brownian dynamics method and by solving the Ornstein-Zernike (OZ) equation in the hypernetted chain (HNC) approximation. The analysis of the structure of the fluids shows that they are locally ordered for large values of Γ*; however, no translationally ordered structures are observed. Isothermal compressibility exhibits nonmonotonic behavior as a function of Γ*. The possibility of a phase transition of the fluid to a vitreous state is discussed. [ABSTRACT FROM AUTHOR]

The problem of implicit expressibility in the three-valued logic P3 is considered. A set of implicitly maximal classes preserving two-element subsets is described. [ABSTRACT FROM AUTHOR]

This paper presents a comparative evaluation of the use of hydrophobized silica materials as functional fillers in ammonium phosphate-based fire-extinguishing powders (FEPs). To this end, we have hydrophobized the surface of different silicas: commercially available fumed silica and Aerosil and monodisperse silica prepared by the Stöber method under laboratory conditions. We have optimized the content of hydrophobized silica fillers in FEPs so that the powder materials exhibit superhydrophobic properties and the lowest flow resistance. [ABSTRACT FROM AUTHOR]

The article describes the experimental approach to elucidate the characteristics of the initial spontaneous boiling (spontaneous boiling-up) and the related effect of attainable liquid superheat. Presented is the analysis of the pioneering works on this subject carried out by G.V. Ermakov in the 60ies under the leadership of V.P. Skripov. They were the “healthy stimulus” for the revival of interest to liquid superheat in the scientific community. The article is devoted to the 80ies anniversary of Ermakov (1938-2012), who has been recognized for a series of investigations on thermodynamic properties of superheated liquids and the kinetics of liquid boiling-up [1]. The article presents discussion of the most striking results obtained in Ermakov’s team and also the previously unpublished results. Selection of issues for discussion was dictated by the preferences of the authors who collaborated with Ermakov. [ABSTRACT FROM AUTHOR]

The detection equipment of the DANSS setup includes 2500 silicon photomultipliers and approximately 100 photomultiplier tubes (PMTs). The system of data acquisition from these photosensors is based on waveform digitization, with which it is possible to simultaneously obtain both amplitude and timing information. The modules of waveform digitizers (WFDs) are made to the VME standard and allow parallel digitization of 64 differential signals at a frequency of 125 MHz with a 12-bit amplitude resolution. The programmable logic of the WFDs provides production of the system trigger based on the analysis of the PMT signals and its propagation without any additional hardware. Owing to the extremely low analog noise, it is possible to use the full dynamic range of the digitization. These WFD modules are superior to other similar modules in the throughput and may find wide application to perform similar tasks of waveform digitization. [ABSTRACT FROM AUTHOR]

The transverse nonuniformity of the light yield in scintillator strips of the DANSS detector was investigated on a test setup that was specially designed for this purpose using proportional chambers with a wire pitch of 1 mm. It is shown that using the approaches that were used in the DANSS experiment, the variation in the light yield due to the geometric features of the strip design is approximately 8% for a minimum ionizing particle. This study can be useful for making estimates and designing similar detectors. [ABSTRACT FROM AUTHOR]

A statistical approach based on Markov chains is proposed for the description of powder-coating wear in slipping friction. A matrix of transition probabilities for Markov-chains corresponding to steady wear is obtained. [ABSTRACT FROM AUTHOR]

Apart from monitoring nuclear reactor parameters, the DANSS neutrino experiment is aimed at searching for sterile neutrinos through a detailed analysis of the ratio of reactor antineutrino spectra measured at different distances from the reactor core. The light collection system of the detector is dual, comprising both the vacuum photomultiplier tubes (PMTs) and silicon photomultipliers (SiPMs). In this paper, the techniques developed to calibrate the responses of these photodetectors are discussed in detail. The long-term stability of the key parameters of the detector and their dependences on the ambient temperature are investigated. The results of detector light yield measurements, performed independently with PMTs and SiPMs are reported. [ABSTRACT FROM AUTHOR]

Alumina with an urchin-like morphology has been synthesized from Al(SO)/CO(NH)/HO/isopropanol mixture via hydrothermal route followed by calcination. Raman spectra and SEM images have shown the urchin-like structure to be formed of γ-AlOOH phase with the component ratio Al/CO(NH)/HO = 1:(2-3):(100-200). The increase in CO(NH) content has resulted in the formation of needle-like crystals of NHAl(OH)CO. Structural transformations of alumina during hydrothermal synthesis have been investigated by SEM and TEM methods. The 5-10 μm urchin-like alumina particles have been found to be composed of 100-200-nm-thick sheets. The alumina samples have been studied by low-temperature nitrogen adsorption method. The adsorption-desorption isotherms and pore size distributions have shown that pore structure of the urchin-like alumina is formed by the slit pores with two open ends. It has been found that after treatment with chlorosilanes the surface of the urchin-like alumina becomes superhydrophobic, the average contact and sliding angle values being 154° and 5°, respectively. Addition of 5 wt% of the hydrophobized urchin-like alumina particles to the model fire-extinguishing powder has made the powder hydrophobic, the average contact angle being increased up to 151°. Introduction of 5 wt% of the hydrophobized urchin-like alumina particles to ammonium dihydrophosphate has resulted in a decrease in the cohesion strength for ammonium dihydrophosphate fire-extinguishing powder from 0.415 to 0.104 kPa. The hydrophobized urchin-like alumina particles can be used as functional additives to the fire-extinguishing powders for the improved flowability and water repellency to be achieved. [ABSTRACT FROM AUTHOR]