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Modern methods of pipe marking are shown. The main factors influencing the retention of marking over time are noted. Own marking method is proposed. The possibility and practicability of magnetic marking of drill pipes are described. Experiments connected with the influence of time and shock loads on retention of residual magnetic induction of are performed. Dependences of residual magnetic induction on the time and the amount of same shock load are made. [ABSTRACT FROM AUTHOR]

Theoretical study of the possibility of interaction of one of the common substances in nature, carbon dioxide, with modified functional carboxyl and amine groups of carbon nanotubes and boroncarbon nanotubes of BC5 type was carried out. The results of interaction were analyzed and a comparative analysis of the efficiency of sorption interaction of the nanosystem with the carbon dioxide molecule was carried out. Recommendations for the further use of the results as a basis for the creation of a highly sensitive sensor device of a new generation for the detection of microcollections of substances are given. [ABSTRACT FROM AUTHOR]

Sorption of heavy metals (iron, zinc, copper) from surface waters by natural and granular glauconite of the Karinsky deposit was studied under dynamic conditions. It was shown that the mechanical strength acquired by natural glauconite as a result of granulation allowed significant increasing filtration capacity of the material and resource of the modeled filter. The exchange capacity of granulated glauconite was equal or exceeded than that of the natural mineral for all studied cations. The sorption characteristics of granulated glauconite allow using it in drinking water treatment schemes for purification of natural waters from heavy metals, while maintaining the pH and hardness values within the limits of the standard for drinking water set by the regulatory norms. [ABSTRACT FROM AUTHOR]

A method for determining sodium dodecyl sulfate (SDS) in solutions after intercalation of layered rare earth metal hydroxides was developed. The method was tested on highly concentrated solutions of SDS (10-70 g/l). The concentration was determined by spectrophotometry of micellar solution that was formed by SDS. [ABSTRACT FROM AUTHOR]

Wavelenght dispersive x-ray fluorescence spectrometry was applied to determine the concentration of trace elements in a solid-phase extraction sorbent. Reference materials were synthesized by analytes sorption from solutions of known concentration. To control the completeness of sorption solutions were analyzed by Inductively coupled plasma mass spectrometry. [ABSTRACT FROM AUTHOR]

The main indicator of ferroalloy efficiency is the degree of absorption of the driving element, which is greatly influenced by physical and chemical properties of the ferroalloy: melting start and end temperature, ferroalloy density, melting duration of ferroalloy and its thermal characteristics. Studying the effect of the chemical composition of ferroalloy on its service characteristics makes possible to predict the degree of assimilation of its leading elements by the steel. The pycnometric method was used to determine density of boron-containing ferroalloys. The density was in the range of 3.8–4.64 g/cm3. Reduction of silicon content to 40–55 wt. % contributes to the density increase, bringing it closer to the range of rational values. The study of the melting point of alloys showed that all alloys were low-melting with a melting point of below 1200 °C. By using a mathematical model, the melting time of ferroalloy was calculated. It is shown that the rational diameter for alloys is 10–20 mm. [ABSTRACT FROM AUTHOR]

Radiogenic Sr isotope ratio (87Sr/86Sr) is widely used for rock and mineral geochronological dating in and for revealing isotopic chemostratigraphic correlations; it is an important tracer for geochemical processes and the sources and cycling of Sr in hydrologic and environmental studies; it is used for provenance studies in forensic science, food security, wildlife migration. Due to the differences in the efficiency of ion extraction, transmission and detection as a function of analyte mass, an isotope ratio measured by inductively coupled plasma mass spectrometry (ICP MS) may by significantly biased from the corresponding true value. This phenomenon is referred to as mass discrimination (mass bias). In this paper, the various methods for correcting the mass bias in the isotopic analysis of strontium are considered. It is found that for standard samples and real samples with a complex matrix, the optimal way for accounting the mass bias is the internal correction according to the exponential law, as well as a combination of the internal correction and the bracketing methods using 87Sr/86Sr = 0.71026. [ABSTRACT FROM AUTHOR]

Influence of magnesium nitrate used as chemical modifier on the temperature of pyrolysis for Al, Ag, Cr, Cu, Sn determination was estimated by theoretical calculations and experiments. Theoretical results were confirmed by the experimental data. The mechanism of the modifier action was determined. [ABSTRACT FROM AUTHOR]

Corrosive impurities causing increased corrosion of the equipment materials in chloroaluminate melts were defined using IR-spectroscopy, differential scanning calorimetry (DSC) and thermogravimetric (TG) analysis. [ABSTRACT FROM AUTHOR]

Oxide phosphors were produced from layered rare earth hydroxides synthesized by controlled double-jet precipitation at constant values pH 7 and 8. After precipitation, hydrothermal processing was carried out, which adversely affected luminescence intensity, but increased the crystallinity of the layered rare earth hydroxides. This makes it possible to obtain luminescent films with increased transparency and homogeneity from such layered hydroxides. [ABSTRACT FROM AUTHOR]

Thermochemical processes of gaseous molecules SrI and BaI formation, which are used in the electrothermal molecular absorption determination of iodine, were studied using the method of thermodynamic simulation. The calculations made it possible to establish that gaseous molecules SrIg and BaIg are formed during the course of the thermal decomposition of gaseous SrI2g or BaI2g, respectively. [ABSTRACT FROM AUTHOR]

The oxidation state of transition metals (Fe, Cu, Cr, Mg, Eu, Ce, etc.) in minerals and synthetic materials is an important indicator of the redox conditions of their formation and evolution, used in solving geological and materials science problems. Experimental data on the oxidation state obtained using bulk methods for nonhomogeneous material samples are low informative. EPMA remains the most common and low-cost method for studying the oxidation state of Fe ions in minerals with micron spatial locality. The assessment of the Fe oxidation degree can be carried out using valence X-ray emission lines FeLα,β. Despite of the variety of approaches and methods for estimating Fe3+/Fetot for a number of minerals, the technique remains undeveloped for the chrome spinel group minerals. This work has been devoted to the selection and verification of sufficiently homogeneous intralaboratory reference samples from the Ural ultramafic massifs. The Fe3+/Fetot content has been estimated according to Mössbauer spectroscopy and indirect calculation approaches. The optimal operating conditions of measurements have been chosen, and spectral noise reduced. Calibration dependences of the maximum of the FeLα line on the FeO content in the reference samples have been obtained, which allow determining FeO concentration with a relative error of 2 % and the value of Fe3+/Fetot with a relative error of 9 %. [ABSTRACT FROM AUTHOR]

Precipitation of strontium phosphates from LiCl–KCl–SrCl2 at 550 °C, and NaCl–KCl–SrCl2 and NaCl–KCl– CsCl–SrCl2 melts at 750 °C was investigated. Sodium phosphate was employed as the source of phosphate ions. The experiments were carried out under static conditions in an inert atmosphere. X-ray powder diffraction analysis was employed for identifying the compounds formed and particle size distribution curves were measured. [ABSTRACT FROM AUTHOR]

The work is devoted to assessment of REM oxides recovery degree in the process of pyrometallurgical reprocessing of spent nuclear fuels. Reduction melting and ICP AES methods were applied. The contribution of inaccuracy from each method was evaluated using the Monte Carlo method. [ABSTRACT FROM AUTHOR]

The paper presents the effect of the pH of the deposition process on the properties of zirconia stabilized with yttrium oxide. It was shown that precipitation at pH = 5 leads to the formation of spherical particles, which do not collapse after firing and have high bulk density and fluidity. The sample obtained at pH = 8 is an aggregate with a wide particle size distribution with a fragmentation shape, not flowing with a low bulk density. [ABSTRACT FROM AUTHOR]

The optimal conditions for the sorption of arsenic and antimony from nickel-containing solutions on freshly obtained manganese dioxide have been found (pH 2, coagulation time of the precipitate 75 min, addition of 2.0 mmol MnSO4 and 0.2 mmol KMnO4 per 50 ml). It was found that the Freundlich model describes the process of adsorption of arsenic and antimony on manganese dioxide most accurately (the correlation coefficient for antimony and arsenic was 0.98 and 0.99, respectively). According to the developed procedure, reference materials of nickel alloys were prepared for further determination of arsenic and antimony using inductively coupled plasma atomic emission spectrometry. The certified and found values of the antimony and arsenic content in the samples were in good agreement. [ABSTRACT FROM AUTHOR]

During crystallization of water and aqueous solutions occurs in the electromagnetic spectrum. Researchers have recorded that the origin of each grain of ice is accompanied by the generation of an electromagnetic pulse. We also assume that the amplitude of the electromagnetic pulse depends proportionally on the change in the area of the monoblock over time. To study this physical phenomenon, a hardware and software system was developed. [ABSTRACT FROM AUTHOR]

In this paper, we consider a system for generating pulses of triggering a thyratron for a nanosecond electron accelerator YRT-1M, operating on equipment for the radiation processing of agricultural products. We use the Single-stage asymmetrical half-bridge converter which allows to increase the frequency of the thyratron trigger pulses generator. This principle has already proved itself in spark gaps switches operating at frequencies up to 5 kHz. [ABSTRACT FROM AUTHOR]

The work is devoted to the investigation of the effect barium addition on physico-chemical properties, catalytic activity of CO oxidation and oxygen storage capacity (OSC) of three-way catalysts. A solid solution of composition Zr0.5Ce0.4 Y0.05La0.05Ox (CZYL) was used as the OSC material. It was shown that addition of barium has the negative effect on the properties of the OSC material. This fact should be taken into account when designing the composition of the three-way catalysts. [ABSTRACT FROM AUTHOR]

Carrier gas hot extraction was used for determining oxygen in FLINAK. Additive and multiplicative components of reproducibility were established. [ABSTRACT FROM AUTHOR]

The researches of the giant magnetoimpedance effect has led to the creation of magnetic field sensors with a sensitivity of millioersteds. On the basis of multilayered ferromagnetic films developed at the UrFU a prototype of weak magnetic fields detector is created. The detector is assembled according to the lock-in amplifier circuit operating at a frequency of 10.7 MHz under the control of the program described in this paper. The program provides DDS control, ADC data reading, mathematical processing of data streams, displaying graphs in real time. [ABSTRACT FROM AUTHOR]

A two-frequency eddy current technique and transducer with rectangular cutouts in a U-shaped core have been developed, which allowed to test the quality of soldering current-carrying joints of the stator windings of hydraulic turbine generators in previously inaccessible areas. A new technique and equipment allowed to determine the degree of soldering of high-power electromagnet conductive cables with variations of their sizes and thereby significantly increased the reliability of the non-destructive testing (NDT) method. [ABSTRACT FROM AUTHOR]

In this paper, we consider a control system for a powerful pulsed electron accelerator operating in an equipment for the radiation processing of agricultural products. The control system consists of hardware made of microchips with microcontrollers and software for a personal computer. The system provides operator safety and isn't sensitive to interference. The software was developed using web development technologies, which makes it cross-platform. [ABSTRACT FROM AUTHOR]

The paper analyzes and simulates the results of a short-wave magnetic antenna for communication in the Arctic region. The advantages of communication in the HF band and the possible implementation of the antenna complex with the ability to work on two sub-bands of the short-wave spectrum are present. [ABSTRACT FROM AUTHOR]

The Arctic attracts the attention of many countries of the world, as it is rich in hydrocarbons. Gas production in the circumpolar region is possible only from drilling platforms. One of the most important tasks on the platform is the task of ensuring the safe work of platform employees. Natural gas is explosive, as in a mixture with air at a certain concentration forms an explosive mixture. To monitor the concentration of natural gas in the most important parts of the drilling platform are sensors that record the concentration of gas and give control signals when a certain concentration level is exceeded. We have developed a mobile device that allows you to determine the concentration of natural gas in those places where there are no stationary sensors for monitoring the concentration. [ABSTRACT FROM AUTHOR]

In this paper, we studied the effect of temperature on the magnetic properties of GdCo-Al2O3 composite films. These films were obtained by magnetron co-sputtering of Gd, Co, and Al2O3 targets in an Ar atmosphere. The magnetic properties were investigated using a vibrating sample magnetometer in the temperature range from 5 to 300 K. It was found that the formation of ferrimagnetic ordering is possible in GdCo-Al2O3 films. Furthermore, the larger the content of the Al2O3 dielectric phase in the film is, the larger volume of Gd undergoes oxidation. [ABSTRACT FROM AUTHOR]

Natural conditions in the circumpolar region are unfavorable for the residents who live there because dermatologists have developed a special technique for general practitioners to early identify skin problems that occur in residents living in the Arctic region. For preliminary diagnostics, we developed a device that allows you to assess the risk of a disease in a patient, send the resulting image to a specialized oncology clinic for decision-making. In addition, the device allows you to save archives of photographs so that a general practitioner can observe the problem in dynamics from 6 to 12 months. This technique allows you to identify skin problems at an early stage and help the patient recover. [ABSTRACT FROM AUTHOR]

New method is proposed for processing a waveform, which was not previously used to determine the voltage drop and the energy introduced into the discharge gap at the electrodes of the installation for the production of nanoparticles by spark discharge. The waveform processing method can be a useful complement to the existing techniques. [ABSTRACT FROM AUTHOR]

Application of bionic design methods in robotics can provide structures with unique decorative and functional properties, since natural structures copied by designer are highly rational in the volume distribution of structural material, ensuring at the same time sufficient strength, rigidity and flexibility. The additive technologies, developed in recent years, allow the designer to manufacture complicated parts of a robot and transfer elements of bionic design to them. In this work, a three-finger gripping device for a fruit sorting robot was designed, taking into account the desired anthropomorphic geometry. Methods of topology optimization and special finite-element (FE) modules of ANSYS software were used to improve design of the gripper. For the task of topology optimization, the finger weight was assigned as the target parameter and minimized under loading conditions, so that high strength and stiffness characteristics of the improved geometry were maintained. As an efficient result, weight minimization reduces the required power of compact drives located on moving parts of the structure. Increase in FE mesh density at each next optimization step allows to form bionic features in the finger geometry and approach anthropomorphic design. Eventually, the optimized fingers of gripper were 3D-printed, which seems impossible to manufacture on CNC machines. [ABSTRACT FROM AUTHOR]

Modern steel production facilities, such as rails, pipe billet (rod), and pipe, use various methods of non- destructive testing. The most promising method of non - destructive testing is magnetic flaw detection using anisotropic magneto resistive sensors of the AMRD type [1]. [ABSTRACT FROM AUTHOR]

In this work, kinematics of human locomotion was studied for the purpose to configure the control system of lower-limb exoskeleton robot. The initial standing-up motion of a healthy man was investigated, and based on the measured coordinates, the normal planar trajectories of knee, hip and shoulder in the sagittal plane were constructed. Thereafter, the main angles to control corresponding drive units of the robot were calculated. Providing natural anatomical locomotion and force assistance, such robot can train individuals suffering from muscle weakness or motion disorders and help them to improve their physical health through the robot-assisted rehabilitation. [ABSTRACT FROM AUTHOR]

NMOS design methodology with increased radiation hardness based on the standard manufacturer's technological libraries is presented. Key model parameters definition are discussed, as well as layout design for parametrized components and connected with layout configuration features when projecting integral layout. Test structures are presented for components characterization in radiation environment. [ABSTRACT FROM AUTHOR]

Optically transparent SiO2 glass was implanted in a pulsed mode with 30 keV Bi-ions with different doses: 1016, 5·1016, 1017, 3·1017 pcs/cm2. The depth of penetration of ions into the studied SiO2 samples was estimated using the SRIM software package and is in the depth range of 10-60 nm. Optical absorption spectra were recorded on a vacuum spectrophotometer McPherson VuVAS 1000 Pl. It has a non-elementary form, which indicates the presence of active centers and structural defects associated with intrinsic defects of silicon dioxide glass, as well as with bismuth ions. [ABSTRACT FROM AUTHOR]

Nanoceramics of Mg1-xMnxAl2O4; x=0.005, 0.00005 was obtained using thermobaric synthesis method. As a result of an increase in the concentration of impurity manganese, the impurity is redistributed over cationic positions, which stimulates lattice compression. The stabilization of the Mn2+ and Mn3+ states was discovered, due to the relatively low temperatures of thermobaric synthesis (not more than 600 °C). It is shown that impurity manganese ions in nanoceramics can act as indicators of structurally nonequivalent tetra- and octahedral positions. [ABSTRACT FROM AUTHOR]

The features of structural state and the temperature-dependent properties of Co-W films deposited by magnetron sputtering directly on glass substrates, as well as on Ru buffer layer were investigated. It is shown that in the Co-W films on a glass, tungsten doping leads to the formation of a highly textured state of hcp crystallites with an axis perpendicular to the sample plane. Using data on the temperature change of magnetic properties, it is concluded that the presence of a crystalline texture is the cause of macroscopic perpendicular anisotropy, which leads to the formation of a magnetic structure of the "trans-critical state" type in a certain range of compositions. The Ru buffer layer slows down compositional structural transformations, which has a corresponding effect on the magnetic properties of the films. [ABSTRACT FROM AUTHOR]

In this paper an express method for measuring sea water pollution using digital holographic microscopy is proposed. The theory of the proposed method is described in detail. The experimental setup is described and the advantages of the proposed method are indicated. In addition, the minimum size of the detected particle is evaluated. [ABSTRACT FROM AUTHOR]

In the mountains of Bolivia, one of the largest lithium deposits in the world is located, which could become a key resource for producing lithium-ion batteries. In this work, analysis of basic technological processes required for manufacturing lithium-ion batteries is performed taking into account the specifics of the raw material base available in Bolivia. An automated line is proposed and designed for the production of lithium-ion batteries with various dimensional and power characteristics in this country. On the automated line, technological processes and zones were identified where it is advisable to install robots, including packaging operations for finished products at the final stage. To design robotic zones, ABB software was used with an extensive library of ABB robots and auxiliary components. The movements of the ABB robots were simulated in the ABB RobotStudio software environment. Draft geometric models of special technological equipment necessary for simulating the automated line were created in the AoutoCAD software. Based on the simulation in off-line programming mode, control programs for robots installed on the automated line have been compiled. A separate study in the framework of this studies was carried out on the problems of using collaborative robots as part of the planned production. [ABSTRACT FROM AUTHOR]

The program of virtual ultrasonic flaw detector lntrotest-1M was developed. The developed model simulates user interaction with the settings menu of the lntrotest-1M ultrasonic flaw detector, as well as simulates measurements of model ultrasonic signals. The program allows you to display and measure model ultrasonic signals, both in the near and far control zone, to study the general trend of propagation of ultrasonic pulses in various materials using various piezoelectric converters. [ABSTRACT FROM AUTHOR]

Temperature dependence of attenuation of ultrasonic transverse normal modes, polarized propagating along the [110] crystallographic axis in SrF2 crystal doped with Cr2+ ions was measured at the frequency of 52–162 MHz in the temperature range of 4–180 K. The results indicated the T2g⊗(eg + t2g) Jahn-Teller effect problem with important impact of quadratic term in the vibronic Hamiltonian. The value of activation energy was derived from the temperature dependence of relaxation time of the sub-system of the Jahn-Teller complexes simulated with account of three mechanisms of relaxation: thermal activation, tunnelling through the potential energy barrier, and two-phonons mechanism similar to Raman scattering. The extrema points of adiabatic potential energy surface: six orthorhombic global minima, three tetragonal and four trigonal saddle points were calculated in 5-dimensional space of symmetrized coordinates. [ABSTRACT FROM AUTHOR]

Testing objects with magnetic methods, the remanent magnetization is important to measure. There are a lot off cases when it is needed to measure magnetic field. For example after magnetic testing of friction parts, to detect defects or to evaluate. General-purpose magnetometer based on hardware-software system DIUS has been developed. The metrological characteristics of magnetometer have been evaluated. The measurement range of the magnetic induction was -40 ... +40 mT. [ABSTRACT FROM AUTHOR]

The results of an experimental study of the surface morphology and structural properties of thin films of gallium nitride on sapphire obtained by pulsed laser deposition are presented. Pulse laser sputtering of gallium nitride films was carried out by sputtering a liquid gallium target in an atmosphere of nitrogen and argon. Using scanning electron microscopy and energy dispersive analysis, it was found that thin gallium nitride films obtained at a fluence of 0.75 J/cm2 have a composition close to stoichiometric. It was determined that a decrease in fluence during pulsed laser deposition of thin gallium nitride films on sapphire reduces the arithmetic average surface roughness to 0.891 nm. films. [ABSTRACT FROM AUTHOR]

Reconstruction project of 110 KV "Baltymskaya" substation is reviewed in detail. The choice of relay protection and automation was made in the work. Also, the main switchgear circuit of the RU was selected, the short circuit modes were calculated and the switching equipment was selected. [ABSTRACT FROM AUTHOR]

In this work, rapidly quenched amorphous cobalt-based ribbons with a metalloid content of 20% and the finemet type ribbons were investigated in as-quenched state. Their structure, magnetic properties magnetoimpedance (MI) behaviour were discussed in the context of the effective magnetic anisotropy peculiarities depending on the length of the ribbons. The experimental results and the results of the finite element model (FEM) calculations for MI were comparatively analyzed. A quantitatively higher magnetoimpedance effect was observed for FEM modeling case, due to the absence of contributions from surface anisotropy, anisotropy distribution and magnetostriction. The results of modeling and experimental studies were in qualitative agreement. Expected change in the type of the field dependence of the MI ratio from one-peak to two-peak was observed. The effective value of the anisotropy field was estimated by fitting the results of the experiment and modeling. [ABSTRACT FROM AUTHOR]

The low-temperature TL properties of anion-defective α-Al2O3-δ crystal were investigated. The installation based on a thermoelectric cooler was created. The kinetic parameters of the low-temperature trap were determined. The results of comparing the intensities of dosimetric peaks when irradiating samples with the same dose at room temperature and at −30° C were obtained. [ABSTRACT FROM AUTHOR]

The morphological stability of a radially displaced fluid in a Hele-Shaw cell is considered in the linear-order perturbation theory. For the first time the unsteady Navier-Stokes equation with an inertial term and the finite sizes of the cell are taken into account. An equation for the perturbation amplitude in dimensionless coordinates is obtained. [ABSTRACT FROM AUTHOR]

Using a global optimization method, the parameters of a pair potential of the interaction of thorium and oxygen ions in ThO2 are fitted, which are compatible with the potential set MOX-07 previously proposed for UO2 and PuO2 crystals. The potential is expressed in the form U(R) = exp(X–Y•R) eV, and the optimal parameter values are X = 8.073687, Y = 3.349 Å−1. Using these parameter values, the potential reproduces the lattice constant of the ThO2 crystal in the entire temperature range up to melting, and quantitatively describes the high-temperature peak in the heat capacity that is associated with the superionic transition. [ABSTRACT FROM AUTHOR]

Calculations of structure and energy of symmetrical tilt boundaries in BCC Ti have been done by the methods of molecular statistics and molecular dynamics. There results of calculations by both methods are compared. The calculated values of energy and width of boundaries in BCC Ti are compared with the available experimental data. [ABSTRACT FROM AUTHOR]

Nanoparticles Ag2S were synthesized by the method of chemical condensation in an aqueous solution. To assess the effect of the stabilizing agent, diluted and undiluted in alcohol MPS and various molar ratios of AgNO3 to Na2S were used. The synthesized colloidal Ag2S solutions were used to make films in several ways. The colloidal solutions and films were studied by dynamic light scattering, optical microscopy, and atomic force microscopy. The stability area of the colloidal Ag2S solution was determined. It was found that the particle size and size distribution in the films depend on the concentration of the starting reagents. The method of creating a thin film with the smallest size of Ag2S nanoparticles was developed. The self-organization of nanoparticles was discovered during the formation of a multilayer film with a diameter of particles from 0.5 to 15 µm. [ABSTRACT FROM AUTHOR]

The interaction of the introduced dispersed refractory particles in the metal during its smelting is simulated in order to obtain composite materials that are resistant to the interaction of radionuclides. The simulation was carried out in the FactSage 7.0 software package. the results of modeling the interaction of the metal phase with yttrium oxide, tungsten carbide, and titanium carbide are Presented. The simulation results showed that even if the added additives do not have time to dissolve when interacting with the metal phase, the iron turns into an oxide melt. It is shown that the components of metal alloys, such as manganese, titanium and chromium, will also be oxidized along with the oxide melt. [ABSTRACT FROM AUTHOR]

It is shown that when an ultrashort pulse of an electromagnetic field is scattered by polyatomic systems, their defects can be determined. The article presents the development of a mathematical apparatus for describing the structure of DNA, in order to analyze the molecule for defects. There are description of radiation spectra, radius vectors of the nucleotides of the molecule, conclusion of the interference factor. [ABSTRACT FROM AUTHOR]