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Modernization of coke production at Magnitogorsk Iron and Steel Works (MMK) is considered, including the construction of a new high-capacity coke battery (annual output 2.5 million t). The use of dry quenching at this coke battery improves coke quality, decreases harmful emissions, and permits power generation. The basic characteristics of the new coke battery are outlined, and its power supply system is briefly analyzed. [ABSTRACT FROM AUTHOR]

The best conditions of surface plastic deformation (smoothing) with simultaneous ultrasound treatment are determined experimentally: specifically, the initial indenter insertion depth; and the angular and linear velocity of the workpiece. It is established that ultrasound treatment increases the surface microhardness. In intense ultrasound treatment, the microhardness reaches 7200 MPa, but chipping is observed at the surface. [ABSTRACT FROM AUTHOR]

Anodic polishing of St45 medium carbon steel (0.45 wt % C) and 12Cr18Ni10Ti austenitic stainless steel in aqueous electrolytes based on ammonium chloride or ammonium sulfate is studied under conditions of natural or force convection. Surface roughness, weight loss of the samples and the current resulted from polishing are measured. A possibility of plasma electrolytic polishing using a setup for the anodic thermal chemical treatment of compounds with a longitudinal electrolyte flow is shown. Polishing regimes are found to decrease the initial surface roughness of the steels from Ra = 1.0 to 0.19–0.22 μm in 5 minutes at a sample weight loss 0.5–0.7 mg/s. The minimal surface roughness is obtained using a 3% solution of ammonium chloride at a flow rate of 0.8 L/min, voltage of 300 V, and electrolyte temperature of 80°C. [ABSTRACT FROM AUTHOR]

The interaction of a terminal thiol group with gold clusters and Au12M intermetallic clusters has been studied by quantum-chemical methods. The energy of addition of the SH group has been found to have the least value for the most stable of the known clusters, which do not change their structure upon addition of the SH group. The highest energy of addition of the terminal thiol group is accompanied with structural modifications of the initial cluster. [ABSTRACT FROM AUTHOR]

Numerical simulation of the hydrodynamics and heat transfer of a dense layer of a highly loose high-concentration granulated medium in a circular bunker on the basis of a non-Newtonian medium with application of the ″power-law liquid″ model and boundary slipping conditions on solid walls is presented. The influence of regime and geometric parameters on the dynamics and heat transfer of a high-concentration granulated medium is investigated. The validity of the results obtained is confirmed by comparison of the numerical results with well-known experimental and analytical data. The results of the investigation carried out can be used in powder technology apparatuses in the processes of drying, mixing, homogenization, batching, and transportation of granulated materials. [ABSTRACT FROM AUTHOR]

Results of field experiments in synchronized investigation of the protection embankment of the tailing pond of JSC Kovdor Mining and Processing Plant by means of different wave methods of electromagnetic and seismic sounding are presented. A comparative analysis of the data is carried out by means of which boundaries of zones of different degrees of water saturation of the embankment soils may be reliably established. The ranges of velocity of the electromagnetic wave and range of values of the ratio of the velocities of the longitudinal and transverse elastic wave in the transition from dry dense soil of the embankment to moistened soil right up through water-saturated soil are determined. [ABSTRACT FROM AUTHOR]

The use of modified detonation nanodiamonds in the most common gold-plating electrolytes—citrate and phosphate—makes it possible to increase microhardness by a factor of about 1.2 and wear resistance from 3.6 times up to that of a practically non-abradable coating, while keeping unchanged the electrolyte formulations, temperature, and current density which are typically used in the conventional technological process. The coating thickness is recommended to be reduced 2- to 3-fold. [ABSTRACT FROM AUTHOR]

The problem of an increase in the Al concentration in the primary coolant of a research nuclear reactor is considered. The dispersion of aluminum hydroxide by fission products of uranium sorbed on the reactor core surfaces is suggested as a possible cause of this phenomenon. The correlation between the Al concentration and the reactor core contamination with uranium was considered with the IVV-2M research nuclear reactor as an example. Contamination of the reactor core with uranium was accompanied by a considerable increase in the activity concentrations of 24Na, 27Mg, and 239Np washed out from oxide deposits on the reactor core surfaces, which confirms the hypothesis put forward. [ABSTRACT FROM AUTHOR]

A new method of loop closure based on storage of local maps of obstacles and meant for reducing accumulated localization errors is proposed. The advantage of this method in comparison with the earlier one is in the decreased amount of RAM. Testing results for the developed system and comparisons with analogs are presented. [ABSTRACT FROM AUTHOR]

A method to improve the strength properties of transmission parts of motor vehicles by application of a wear-resistant coating by an ultrasonic method making it possible to obtain thin highstrength layers is proposed. When applying the alloy material over the processed surface, an analytical method of elaborate selection a coating strengthener is used. The results of a study of toothed gear wheels of the transmission of motor vehicles with respect to strength, wear resistance, and noisiness of their work are presented. [ABSTRACT FROM AUTHOR]

The effect of conditions of anodic electrolytic-plasma borocarburizing of low-carbon steel on its structure and properties has been studied. It has been established that the effect of the treatment conditions on the thickness of a modified layer is explained by the competition of boron and carbon diffusion and steel-sample oxidation. The mechanism of transport of saturating components from electrolyte into steel is described. An electrolyte composition (10-15% sal ammoniac, 5% boric acid, and 4-8% glycerine) and treatment modes (800-900°C, 5 min) are suggested that produce a hardened surface layer with a thickness of up to 0.15 mm and a microhardness of 1000 HV and reduce surface roughness by an order of magnitude. Anodic electrolytic-plasma borocarburizing makes it possible to reduce the coefficient of friction by 36%, steel-wear rate by an order of magnitude, and corrosion rate by 2.5 times. [ABSTRACT FROM AUTHOR]

One of the stages preceding the failure of fuel elements in research reactors with uranium-molybdenum dispersion fuel is the formation of bulges in the fuel-element cladding with accumulation of gaseous fission products in them. It is impossible to validate the operational safety of fuel elements with such fuel if the behavior of gaseous fission products under such conditions is not understood. The results of experimental determination of the free volume of bulges and the volume, composition, and pressure of the gaseous fission products in them are presented. [ABSTRACT FROM AUTHOR]

This paper discusses the features of training simulation for solving problems of visual and instrumental observation and observation of the Earth from the Russian Segment of the International Space Station (ISS). Approaches satisfying the requirement of real-time rendering of the digital visual Earth model with a resolution of up to 15 m/texel with viewing angles of 2 to 110° in a simulation of ISS flight are described. A solution is presented which allows simulating camera observations using a positioning system. The characteristics of the developed software and hardware are given. [ABSTRACT FROM AUTHOR]

This article discusses the activities of the company Tulachermet in implementing measures to protect the environment and the company's plans in this area up to the year 2017. Data is reported on changes in the effects of factory operations on air quality and the water basin. A description is given of measures that will significantly alleviate adverse environmental impacts by reducing harmful atmospheric emissions, reducing discharges of waste water into reservoirs, and cutting back on the accumulation of production wastes. Plans are discussed that will make it possible to further mitigate harm to the environment. [ABSTRACT FROM AUTHOR]

The components of a slag-forming mixture for the ladle treatment of steel are considered. The ratio of the mixture components is calculated, and the main characteristics and thermophysical properties of the mixture at high temperatures are determined. [ABSTRACT FROM AUTHOR]

Heat transfer in a three-phase electrochemical system consisting of a metal cylindrical anode (a workpiece), a vapor-gas envelope, and an electrolyte solution is considered. The purpose of the study is to determine the effect of the length of the sample part contacting with the electrolyte on the distribution of the heating characteristics on its surface. It is established that the increase of the length of the part of the anode submerged into the electrolyte causes a decrease in the average current density, reduction in the vertical current density gradient, and a decrease in the density of the heat flux from the envelope to the sample. A model is proposed to calculate the stationary cylindrical anode temperature and the current in the system with the evaluation of the convective heat flux from the anode portion protruding above the electrolyte into the atmosphere. The influence of the electrolyte flow along the sample on its temperature and the average current density in the system is determined and attributed to the variation of the vapor-gas envelope thickness. [ABSTRACT FROM AUTHOR]

This study is devoted to the effect of the oxide layer formed upon anodic plasma-electrolytic carburization on the rate of carbon diffusion in low carbon steels upon application of an aqueous solution of ammonium chloride with glycerol as a working electrolyte. Approximate determinations of carbon distribution in the surface layer of low carbon steels after their anodic plasma-electrolytic carburizing confirmed the hypothesis that there is deceleration of carbon diffusion by the oxide layer. Different structures of the oxide layer were revealed that depend on the method of sample cooling after their saturation with carbon in an anodic vapor-gas envelope. A possibility of controlling the thickness of the oxide layer was shown, as well as clarification of the surface by the choice of an electrolyte and treatment mode, was shown. A reduction in the roughness of the carburized surface from 0.62 ± 0.02 to 0.22 ± 0.02 μm was revealed. [ABSTRACT FROM AUTHOR]

A study of the extraction kinetics of indium-zinc chloride with molten salt from lead-tin alloys and the effect of the molten salt compositions have been performed. The dependence of the positive effect of ammonium chloride and lead chloride on the kinetics of the extraction of indium from molten metal to salt has been revealed. The results of this research can be used in the development of the industrial extraction method and the extraction apparatus of indium from tin-lead alloys and secondary waste. [ABSTRACT FROM AUTHOR]

This paper was heard at an RAS Presidium meeting and described the structure and current state of the Russian electric power industry and the factors adversely affecting its reliability. The main ways to improve the reliability and efficiency of the industry were discussed, and recommendations on practical implementation of the planned measures to improve the stability of the Russian Unified Energy System are provided. [ABSTRACT FROM AUTHOR]

The interactions that take place in the corium melt in the reactor vessel in the case of a severe accident at a nuclear power plant were investigated in accordance with the MASCA international program. Results of the interaction between the oxide melt and iron (steel), partition of the main components [U, Zr, Fe (stainless steel)] between the oxide and the metal phases of the melt, partition of low-volatile simulators of fission products between the phases of the stratified core melt pool, and impact of the oxidizing atmosphere on the melt stratification are presented. The results obtained were used for prediction of thermodynamic properties of the melts belonging to the U-Zr-Fe-O system. [ABSTRACT FROM AUTHOR]

The structure of carbon steels after their saturation with nitrogen and carbon under conditions of anode heating is studied using metallographic and x-ray analyses and the method of nuclear backscattering of protons. The possibility of raising the corrosion resistance of the carbon steels and of alloy steel 12Kh18N10T under corrosion close to atmospheric one is demonstrated. [ABSTRACT FROM AUTHOR]

A protease activity may be determined by means of immunoglobulins. Since proteolytic products apparently do not retain antigenic determinants of the initial substrate, the monitoring of enzymatic process may employ ELISA methods. The ELISA determination of functional activity of specific IgA1 protease has been used not only for detection of this enzyme, but also for measurement of its inhibition constants. IgG adsorbed onto a microplate was used for evaluation of total proteolytic activity. Varying pH values of the reaction medium it is possible to measure activity of neutral, alkaline and acid proteases. This approach was used for estimation total proteolytic activity of neutral proteases in blood serum. Due to high sensitivity of this method it was possible to dilute serum up to the level when serum inhibitors had not blocked enzyme activity. Assay of serum enzyme activity at acidic pH results in activation of pepsinogens and determination of pepsin activity. Measurement of a total level of serum pepsinogen activity may have diagnostic importance in gastroenterology, due to decisive contribution of pepsinogen I to the detectable activity. [ABSTRACT FROM AUTHOR]

An expression for the density of the heat flux acting between a vapor-gas sheath and a vertical cylindrical anode has been obtained from solution of the heat-conduction equation in the vapor-gas sheath and experimental measurements of he anode-specimen temperature. It has been shown that the heat flux from the sheath to the anode acts just in the lower part of the system. In its upper part, heat fluxes are directed from the anode to the sheath, which limits the possibility of applying the heat-transfer coefficient to description of heat exchange in anodic heating. The values of the vertical temperature gradient in heating of the cylindrical anode and the fraction of heat coming into it have been measured. [ABSTRACT FROM AUTHOR]

The results of investigations of the interaction of U-Zr-B-C-O melts with steel, which are performed as part of the OECD Masca international program, are presented. It is found that, as a result of the interaction, boron and carbon become concentrated predominately in the metallic phase of the melt. As the initial mass ratio mFe/mmelt increases, the effect of the addition of B4C on the melt-iron interaction decreases because the metallic phase is diluted with iron. It is concluded on the basis of a comparison of the results of the STFM-B Nos. 3, 7 experiments with the STFM-Fe Nos. 3, 7 experiments performed previously without the participation of boron carbide that the effect of boron carbide on the interaction of the oxide melt with iron decreases as the degree of oxidation of zirconium increases. [ABSTRACT FROM AUTHOR]

Abstract  The results of investigations of the interaction of U-Zr-B-C-O melt with steel, performed as part of the OECD MASCA program, are presented. It is established that the presence of Mo, Ru, Sr, Ba, Ce, and La in the melt does not qualitatively affect the interaction with structural steel and the character of the stratification of the melt in the reactor vessel. The partition factors of the fission products between the oxide and metallic phases are determined as a function of the oxidation of the melt, the ratio U/Zr, the composition of the structural steel, and the temperature. [ABSTRACT FROM AUTHOR]

Abstract  The results of investigations of the interaction of oxide melt with steel, which were performed following the international OECD program Masca, are presented. The experimental conditions simulated the high-temperature stage of a serious accident in a VVER-1000 vessel. It is determined that the temperature range 2500–2600°C oxide and metallic phases which are immiscible in the fused state form as a result of the interaction of underoxidized melts C-32–C-70 (U/Zr = 1.2). Fused iron is saturated with uranium, zirconium, and oxygen. The density of the metallic phase becomes greater than the density of the oxide melt, which causes the metallic phase to move to the bottom of the pool. The compositions of the coexisting oxide and metallic phases are determined. This can serve as a basis for constructing thermodynamic models of melts in the U-Zr-O-Fe system. [ABSTRACT FROM AUTHOR]

The results of an experimental investigation of the hydraulic characteristics of clusters of twisted self-spaced rods on initiation of possible damages of their integrity are presented. For some probable breakdowns of clusters in their flow region the influence of these disturbances on the coefficient of hydraulic resistance of a packet of rods and on the distribution of velocities of the working body in the cross section of a cluster are investigated. The data obtained can be used for predicting the change in the thermal state of the active zone of the reactor, in particular, of the reactor of power plants under conditions of possible failure of fuel elements. [ABSTRACT FROM AUTHOR]

Abstract  An approach is proposed to detect deficiencies in isotypes A and B of the C4 component of human complement, based on the calculation of the ratio of their IEA activities and the ratio of their quantities determined by isoelectrofocusing of their desialated forms with chemiluminescent detection in an immunoblot. The ratios of the quantities and activities of C4A/C4B practically coincided when determined in blood serum of 20 patients, many of which had inherited deficiencies in the C4 component isotypes. [ABSTRACT FROM AUTHOR]

The neutron spectrum has been measured at the center of the core in the ИBB-2M research water-moderated water-cooled reactor. A technique has been developed to measure the energy spectrum of neutrons in high-intensity fields (with a flux density of >1012 cm−2 s−1) without recourse to fission detectors enclosed in boron shields. [ABSTRACT FROM AUTHOR]

This paper is devoted to the study into the structure of core melts of reactors such as water-moderated water-cooled power reactors. The quenching method is used to experimentally investigate the structure of U-Zr- O melts with an atomic ratio of U/Zr = 1.2–1.6 at a temperature of 2773 K. It is found that, for the most probable compositions of U-Zr-O melts under conditions of heavy accident with the Zr oxidation level above 30%, no separation of the corium melt into immiscible liquids is observed. [ABSTRACT FROM AUTHOR]

This work is devoted to the development of new composite materials for immobilizing medium- and low-level radioactive wastes. The most promising existing methods of solidification are low-temperature processes because they do not require complicated equipment and are cost-effective. As a result of the higher cost-effectiveness, less inert binder is needed in the overall volume of the solidified compound. Thus, using a complex phosphate, making it possible to increase the concentration of toxic products while maintaining reliable immobilization of the latter, is certainly a topical problem.Two advantages of phosphate ceramic are that high concentrations of anions which adversely affect the longevity of cement monoliths can be included and the spectrum of types of wastes that can be handled, including sol residues of combustion and mercury-containing wastes, is wide. [ABSTRACT FROM AUTHOR]

The density of a UO2–ZrO2 melt (atomic ratio U/Zr = 1.528) is experimentally measured by a pycnometric method in the temperature range of 2973–3373 K. The found temperature dependence of density has the form ρ(T) = (7.0 ± 0.01) – (4.5 ± 0.4) × 10–4 × (T – 2973 K), g/cm3. The temperature dependence measured enables one to calculate the values of the density of UO2–ZrO2 melts depending on the temperature and composition for any atomic ratio U/Zr. [ABSTRACT FROM AUTHOR]

Combustion of composites based on granulated cellulose nitrates and containing, as fillers, aluminum oxide, silicon carbide, carbon, boron nitride, sodium chloride, zinc oxide, and tungsten particles, is studied. Burning rates under atmospheric pressure, combustion‐front temperatures, and mass losses after complete combustion of the composites are measured. The dependence of the burning rate on the size of silicon‐carbide particles is obtained. Models of solid and laminar combustion are used to predict combustion characteristics, which are in good agreement with experimental data. Some specific features of combustion of composites with particular fillers are explained. [ABSTRACT FROM AUTHOR]

The results of investigations of the electrochemical behaviour of multicomponent lead–tin alloys under cathodic polarization in a sodium hydroxide melt are presented. It has been shown that as a result of the formation of intermetallic compounds, such elements as antimony, tin, bismuth and arsenic are extracted from the cathode to the anode. The electrolysis product on the cathode is lead with a total percentage of the above impurities of 0.065–0.070%. The extraction kinetics have been studied, the dissolution rate constants for each of the alloy components have been determined and a mechanism of mass exchange between the electrodes has been proposed. The current consumption for the extraction of metals from the melt has been determined. [ABSTRACT FROM AUTHOR]

A computational-theoretical analysis is made of a system of the required properties of potential materials for use as buffer material in the trap for VVÉR-1000. The analysis points to Al2O3 and Fe2O3 as the main candidates. On the basis of the advantages and disadvantages noted for each of them individually, solid solutions based on Al2O3 and Fe2O3 are of interest for practical applications. Estimates show that taking account of the expected degree of oxidation of zirconium in melt and the volume limitations of the trap, the optimal compositions can be equimolar solid solutions Al2O3–Fe2O3. Estimates are confirmed by experiments investigating the character of the phase diagrams and the interaction of core melt with oxide solutions based on systems Al2O3–Fe2O3. [ABSTRACT FROM AUTHOR]

The inhibition of covalent binding of the nascent C4b fragment of the human complement component to its natural target, immunoglobulin G, was studied. To this end, an immunoenzyme system was developed. In this ELISA method, the complement was activated on the sorbed IgG molecules and the resulting nascent C4b fragment acylated IgG or interacted with a competitive inhibitor added to the system. The inhibition constants for binding of the nascent C4b to its target were determined for immunoglobulins G1, G2, G3, G4, M, and A1, as well as for ferritin, yeast mannan, capsid polysaccharides of the Neisseria meningitidis A, B, and C serotypes, diphtheria anatoxin, epinephrine, and salicylic acid. On the basis of the experimental data, the immunoglobulin role at the activation stage of the complement regulation cascade, the relationship between the antigen immunogenicity and its ability to interact with C4b, and the direct effect of a number of therapeutic agents on the complement system were discussed. Lectins of various specificities were shown to inhibit the enzymic activation of C4 by the first complement component and the subsequent C4b sorption by its target, which allowed us to suggest that some oligosaccharide fragments of the C1s and C4 molecules are spatially close to the C1s active site and to the thioester bond of C4. [ABSTRACT FROM AUTHOR]

The difference in the functional activity of the isotypes A and B of component C4 of human complement was used to determine their ratio and to detect the inherited deficiency of the isotypes. ELISA methods were developed for the quantitative assay of component C4 (conventional sandwich method) and its functional activity. When determining the functional activity, the classic pathway of the complement and therefore of component C4 was activated on activators sorbed on ELISA microplates: immunoglobulin IgG3 or liposaccharide of the Shigella sonnei cell walls, which activates the complement by binding component C1. The nascent fragment C4b is covalently bound to the target activator; C4Ab binds better to the target protein (immunoglobulin), and C4Bb to the target carbohydrate (liposaccharide). Therefore, when immunoglobulin is a target activator, isotype C4A is bound and determined; and when the complement is activated with liposaccharide, isotype C4B is determined. The radio of the activities determined by the two methods indicates the deficiency in the individual isotypes of component C4 or its absence. The rabbit polyclonal monospecific antibodies against the human component C4 and the conjugates of these antibodies with horseradish peroxidase were used in the methods described. [ABSTRACT FROM AUTHOR]

A gene of human tumor-associated antigen VNTR(MUC1) bound to streptavidin, an expression plasmid, and a highly effective hybrid protein-producing strain were constructed. It was shown that the streptavidin leader peptide ensures effective secretion of the hybrid protein into the periplasmic space of Escherichia coli cells. The hybrid protein was isolated in a homogeneous state and its immunogenic properties were studied. [ABSTRACT FROM AUTHOR]

The article presents a study of the possibilities of formation of 13-atom clusters with 12 gold atoms and one metal atom. The study shows that the 18-electron species has a larger energy gap between the lower excited orbitals and the upper occupied. It reveals that the existence of two stable forms varying in charge makes nanoparticles of gold and intermetallic clusters promising candidates for functional ligand transport.

Reports on the eightieth anniversary of the A.F. Ioffe Physicotechnical Institute in Saint Petersburg, Russia, founded by A.F. Ioffe. Decree specifying the creation of the State Roentgenological and Radiological Institute; Staff members of the institute who became Nobel prize winners; Areas of research conducted at the institute.

An experimental study is made of a “chemical arc”, a model layered system of solid components, between the end surfaces of which stationary combustion takes place. The rates of combustion of the components in ammonium perchlorate-polyether, ammonium perchlorate-polyethylene, and ammonium perchlorate-butyl rubber systems with catalytic additives (diethyl ferrocene, epoxyethyl ferrocene, and iron oxide) are measured as functions of the distance between the components. A maximum mass combustion velocity is found to exist as a result of the transition from a low velocity (kinetic) to a high velocity reaction regime. The data are in qualitative agreement with theory. The mechanism by which the catalysts affect the combustion characteristics is analyzed. [ABSTRACT FROM AUTHOR]

The history and basic results of work on nuclear rocket motors (NRMs) in Russia are presented. S.P. Korolev, I.V. Kurchatov, M. V. Keldysh, A. P. Aleksandrov et al. stood at the source of the work in this direction. Our NRM reactors used a heterogeneous scheme with a modular core. This enable component-by-component debugging of the reactor experimentally to the required degree of reliability. Ultimately, the costs of the complex tests were minimized, and technical characteristics obtained exceeded those obtained abroad. The energy-release density in the fuel elements reached 30 kW/cm3, and the temperature and rate of heating of the working body (hydrogen) reached 3100 K and 1000 K/sec, respectively. [ABSTRACT FROM AUTHOR]

We measured the temperature dependence of electrical conductivity and emf of a hot pressed chamotte refractory containing dry ACPB in the range 293-533°K. It was shown that the phenomenon of thermoplasticity is accompanied by anomalies in the temperature dependences of the emf and conductivity. In this case, the appearance of the anomaly of emf coincides with the onset of plastic deformation and the abnormality (discontinuity) in the temperature dependence of conductivity occurs during the final stage of specimen deformation. [ABSTRACT FROM AUTHOR]

The spalling resistance of chamotte refractories for stoppers can be increased and spoilage during their production reduced by adding a plasticizing substance, viz. paraffin wax, to the body. [ABSTRACT FROM AUTHOR]