bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of Ti-6Al-4V Alloy In Situ Manufactured Using Selective Laser Melting from Elemental Powder Mixture
Authors: Polozov Igor , Sufiiarov Vadim , Popovich Anatoliy
Published: January 2020

This paper presents the results of the study of Selective Laser Melting (SLM) process for the in-situ synthesis of Ti-6Al-4V alloy from elemental powder mixture. Elemental spherical powders of Ti, Al and V were used to prepare a powder mixture, and then bulk specimens were produced by SLM using different process parameters. The effects of SLM process parameters on samples’ relative density, their chemical composition, the formed microstructure and microhardness before and after heat treatment have been studied. It was shown that volume energy density during the SLM process significantly effects the microstructure and microhardness of Ti-6Al-4V obtained from elemental powders. The difference in microstructure morphology and microhardness remains after heat treatment.
Increasing Wear Resistance of Chizel Tools Working Bodies Based on Improving the Metallographic Structure of Grey Cast Iron
Authors: Motorin Vadim A. , Kostyleva Ludmila V. , Gapich Dmitry S.
Published: January 2020

The article concerns developing and implementing the technological principles for manufacturing the working bodies of chisel tools by casting grey cast iron with partial chilling of its working edges and surfaces interacting with the soil layer. High wear resistance of the working body is achieved by chilling its working part by means of a chill inserted into the mold, or by absence of coating in the corresponding zone of the mold. Severe overcooling of liquid cast iron contacting the chill or the metal surface of the mold causes crystallization of the meta-stable eutectics, and in the chilled part it acquires a ledeburite structure, the hardness being not lower than 64 HRC. At the same time, the bulk of the cast iron crystallizes in the stable system, forming austenitic-graphite eutectics and after complete cooling, it should have a pearlitic metal base, ensuring good machine ability of casting by cutting. Working surfaces and cutting edges of chisels are exposed to abrasive and chemical impacts of the soil, causing intense wear, the latter being the main reason for their failure. The utilization of the given technology will allow increasing service-life of the working bodies and improve the manufacturability, according to the criteria for labor intensity and casting mold making.
Study of the Influence of Heat Treatment on the Structure and Properties of Aluminum-Copper Multilayer Systems
Authors: Pronichev Dmitri , Gurevich Leonid Moiseevich , Slautin Oleg V. , Serov Aleksey
Published: January 2020

Multilayer intermetallic composite materials of the aluminum-copper system are obtained using a complex technology, including explosion welding, rolling and diffusion heat treatment. The structure, composition and properties of the obtained 9 and 15-layer systems were studied and it was shown that the applied technology makes it possible to obtain qualitative multilayer systems with a large proportion of intermetallide phases, that have properties that are significantly different from the base metals, which makes it possible to expand significantly the areas of application of aluminum composites-copper.
Comparative Characteristics of Free-Machining Steels of Cr-Mo Type
Authors: Ryabov A.V.
Published: January 2020

The work investigates the properties of lead-free free-machining steel grade A30KhMAR, containing BN inclusions, in comparison with the base Cr-Mo steel 30KhM, lead-bearing AS30KhM, lead-calcium-bearing ASTs30KhM, calcium-bearing ATs30KhM, bismuth-calcium-bearing AVTs30KhM and tin-bearing AО30KhM. Effect of bismuth, calcium, lead, tin and boron nitride inclusions on steel susceptibility to temper brittleness and cold brittleness is studied. Contamination of steels with non-metallic inclusions is estimated. End-quench hardenability curves of the test steel A30KhMAR are obtained. Free-machining Cr-Mo structural steel, containing low-melting elements, has ASTM grain size of the number of 7–8. Hardenability and austenite grain size are satisfactory compared to the base steel 30KhM. Mechanical properties of the test steel in longitudinal direction (ultimate and proof stress, specific elongation, reduction in area, impact toughness, hardness) were also determined. It was found that bismuth, calcium, lead, tin, boron and nitrogen (in the form of boron nitride inclusions) within the studied limits do not have negative effect on mechanical properties of heat-treated ASTs30KhM, ATs30KhM, AVTs30KhM, A30KhMAR and AО30KhM steels, and the values of strength, plasticity and toughness characteristics satisfy the requirements of GOST standards for the base steel 30KhM and lead-bearing steel AS30KhM.
Efficiency Upgrading for Blast Furnace Smelting through Use of Iron Ore Raw Materials with Various Fluxing Degree
Authors: Yur'ev Boris P. , Gol'tsev Vladimir A. , Dudko Vyacheslav A.
Published: January 2020

Firing of various basicity pellets and sintering of Kachkanar concentrates were evaluated on a pilot plant. Mineral analysis was carried out for fired pellets and those reduced in a derivatograph in gas with composition close to that of blast furnace gas. Structure and metallurgical property dependence of pellets and agglomerate on their basicity was studied. Failure mechanism of fluxed pellets was considered. Blast furnace smelting process was developed for Kachkanar iron ore raw material with various fluxing degree, consisting of low-basic pellets, and high basic agglomerate characterized by low failure characteristics at reduction and ensuring high gas permeability in blast furnace top. Optimal values of agglomerate basicity, carbon content in burden and ferrous oxide in agglomerate, ensuring its high reducibility and adequate reduction degree index, were determined. Optimal ratio of pellets and agglomerate in a blast furnace, which implementation contributes to improved furnace performance, was detected.
The Calculating Method of Thinning Pipes Ends before Rolling in the Reduction Mill
Authors: Orlov Grigory A. , Orlov A.G.
Published: January 2020

In this article it is discussed one of the main directions of improving the rolling tubes technology on a pipe-rolling plant with a continuous mill, in order to reduce the pipe-ends cut. A method for preliminary end sections thinning modes, calculating during rolling on a continuous mill, to compensate for wall subsequent thickening in the reduction mill, has been developed. Method distinctive feature is the calculation of end thickening volume, which must be reduced by a specified quantity when end sections rolled. The sequence of technological calculations is given. The results of pipe reduction computer simulation by regular rolling modes, and modes calculated by the proposed method, are represented The analysis of the simulation results showed the possibility of thickened ends length reducing of at least 10%.
Computer Simulation and Study of the New Forging Technology of Billets in a Step-Wedge Dies
Authors: Tolkushkin Andrey O. , Lezhnev Sergey N. , Naizabekov Abdrakhman B.
Published: January 2020

The paper presents the results of a computer simulation of the drawing process in the step-wedge dies of two configurations: with wedge-shaped protrusions in the first and second sections of the top and bottom dies, and with a wedge-shaped protrusion in the first and second sections of the top die and wedge-shaped cavity in the first and second sections of the bottom die. A comparative analysis of the stress-strain state and energy-power parameters is carried out. Based on the analysis conclusions about the feasibility of choosing a specific configuration of step-wedge dies depending on the set aim were made.
Influence of Plasticizers on the Properties of Fine-Grained Polymer Concrete
Authors: Kapustin Fedor L. , Kapustin A.F.
Published: January 2020

Polymer concretes are used in construction, engineering, electrical and chemical industries. Polymer concrete mixes are characterized by low mobility mixtures, due to their high viscosity. It makes difficult to use them in the production of thin-walled and high-reinforced structures, monolithic floors, application of finishing and protective coatings and repairing of roads. The influence of additives of dibutyl-phthalate, chlorinated paraffin, technical glycerin and engine oil on the mobility of the concrete mix and the physical and mechanical properties of fine-grained concrete, based on polyester resin, was studied. For polymer concretes with different type and quantity of plasticizer the density and bending and compression strength were determined. To improve the workability of the concrete mix and obtain a polymer concrete with a homogeneous structure and high strength, it is recommended to use chlor-paraffin ChP-470A and “Lukoil” engine oil as a plasticizer.
Investigation of Grey Iron Primary Structure Influence on Hollow Castings Strength
Authors: Grusha V.P. , Bevza V.F. , Baron Aleksandr A.
Published: January 2020

For the hollow cylindrical grey cast iron billets, received by method of the directional solidification on the section of a wall, structural changes are investigated. Micro-hardness in zones of dendritic crystals and the eutectic matrix are determined.
The Effect of Silicon in Al-Si Alloys and Electrical Treatment Modes on Structure and Properties of MAO-Coatings
Authors: Dudareva N.Yu. , Gallyamova Rida
Published: January 2020

The work shows the influence of the content of silicon in the aluminum alloy and the regimes of micro-arc oxidation (MAO) on the structure and properties of the formed coatings. Treatment of samples from high-silicon aluminum alloys AK12pch (Si ~12 %) and M244 (Si ~25 %) was carried out in two modes, which have different installation capacity MAO. The thickness, micro-hardness, porosity of the formed MAO coatings was investigated. It is established that the increase in the proportion of silicon in the aluminum alloy leads to the formation of MAO coatings of significant thickness (~230 μm), with low micro-hardness (HV ~650) and high porosity (up to ~16 %). Increase 4 times the installation capacity of MAO causes the growth of the thickness of the coating, reduces the porosity of the coating on the alloy AK12pch and increases the porosity of the coating on the alloy M244.
The Application of Catalytic Coatings Ion Implantation Method
Authors: Zlobin Vladimir N. , Sorokin A.M. , Kudashev Aleksey S.
Published: January 2020

The advantages of ion implantation method compared to existing methods of vacuum deposition. It was shown that the surface properties may vary within a wide range. The specific surface of the sample material may increase after the surface treatment. As a result of implantation the surface enhances catalytic activity and modifies the mechanical properties. There is a presentation an ion implanter for the implementation of the method and how it works. A process for applying the catalytic coatings working surfaces for various purposes is disclosed. The results of X-ray diffraction analysis of samples are introduced into the surface by alloying the catalyst corpuscular ions. The research on prototypes of various shapes. As a result, comparing them with samples.
Kinetics of Diffusion Interaction in Cr15Ni60-AD1 Layered Composite
Authors: Shmorgun Victor Georgievich , Bogdanov Artem I. , Shcherbin D.V.
Published: January 2020

The structure, phase and chemical composition of the diffusion interaction zone, formed at the interlayer boundary of a layered composite of the alloy Cr15Ni60-aluminum AD1, are studied. The temperature-time conditions for its nucleation and growth are determined. The diffusion zone has a fine predominantly heterogeneous structure and consists of solid solutions based on aluminides Al3Ni, Al3Ni2 and Al7Cr, as well as the ternary compound Al5FeNi. It is shown that the intensity of diffusion zone growth at the interlayer boundary of the bimetal Cr15Ni60-AD1 is determined mainly by the heating temperature, and the dependence of its thickness on the exposure time obeys a parabolic law. The presence of chemical micro-inhomogeneity in the form of a melted metal at the interlayer boundary does not have a qualitative effect on the kinetics of the process: at the first stage, the diffusion zone repeats the contour of the fusion, and then, as the service time increases, «absorbs» it.
Connection of the Steel Pipes Having a Polymeric Covering on Internal and External Surfaces
Authors: Savin Igor A. , Akhmedeev M.
Published: January 2020

The article investigates the issues of pipeline transport and the methods of protecting pipelines from corrosion, as well as the manufacture of pipes with internal and external coatings and proceeding construction of pipelines. The main objective of this article is to obtain a reliable and durable pipeline with internal and external coatings, as well as to preserve pipeline capacity and ease its installation.
Optimizing the Performance of Electroplating Gas-Cleaning Equipment
Authors: Nitskaya Svetlana G. , Smolyakova K.R. , Shmidt Irina V.
Published: January 2020

Electroplating industry has by-products, most of which are harmful. The paper considers the issue of removing aerosol emissions during chrome coating. We developed a droplet separator, which was granted a patent for a useful model. Based on the model, we proposed a stage-by-stage technical procedure for cleaning gas-air mixture to optimize the performance of gas-cleaning equipment during hard chrome coating. We calculated the amounts of water vapor and chromic anhydride which is released during chrome plating without cleaning and when using the developed procedure for gas mixture cleaning. We determined maximum surface concentrations of pollutants in exhaust gases after cleaning.
Activity of Zinc Oxide Based Spinels Catalytic
Authors: Shabelskaya N.P. , Semchenko V.V. , Deeva A.S.
Published: January 2020

Comparative assessment of phase formation in the system ZnO-CeO2-Fe2O3-Cr2O3, obtained using a number of technological methods, is carried out. Spinel phase formation is established for all materials studied, except ZnO-CeO2. Synthesized materials are examined with X-ray phase analysis, low-temperature nitrogen adsorption, and scanning electron microscopy. It is shown that the synthesis in the presence of an organic precursor allows obtaining fine spinel samples. High catalytic activity of the synthesized materials, containing the spinel phase, is established in the process of methyl orange oxidative destruction in the presence of hydrogen peroxide. It is proved that with an increase in the number of chromium cations in the sample, the catalytic activity of the materials also increases. Zinc ferrite, despite the considerably more developed surface, and ZnO /CeO2 are not very effective in this process. The data obtained is useful for the development of materials for wastewater treatment at industrial enterprises, which use organic dyes in their production cycles.
Study of the Micro-Hardness of Anti-Friction Coating after Plastic Deformation in Bimetallic Sliding Bearings
Authors: Rodichev Alexey Yu. , Gorin Andrey V. , Tokmakova Maria A.
Published: January 2020

The article presents the results of experimental studies of the micro-hardness of anti-friction surfaces of bimetallic sliding bearings. As a result, the nature and features of the process of distribution of the micro-hardness of the coating along the height of the anti-friction coating were revealed. A method of manufacturing a bimetallic sliding bearing is proposed, which will allow an increase in the micro-hardness of the anti-friction coating and its uniform height distribution. This method allows to reduce the porosity of the anti-friction coating and to achieve the specified processing parameters of the anti-friction surface.
Comparative Study of High-Chromium Cast Iron Coatings Modified with WС-W2C/Co+B4С+Ni/Al Complexes and Cr3C2/PG-US25 Ceramet
Authors: Shchegolev Alexander V. , Ishkov Alexey V. , Ivanaysky Victor V.
Published: January 2020

The article describes the preparation and comparative wear resistance testing Fe-Cr-C- (B) coating materials, intended to harden the working bodies of agricultural machines, using high-performance method of inductive surfacing, and contains the results of microstructure analysis of such coatings. These coatings are made of powder compositions, based on PG-US25 high-chromium cast iron, and borate flux for inductive surfacing of P-0.66 grade, modified with W, B, Cr carbides in amounts from 2...5 to 25...30 wt.%, which can be applied to machine’s elements without significant technology changes. Modifying agents were commercial products (WC-W2C / Co spherical cast tungsten carbide, B4C abraser). The article demonstrates that the injection of these complexes into the fusion mixture for inductive surfacing can increase their hardness (up to 1000...1200 HV100) and wear resistance of the surfacing metal 3.1...4.5 times, compared to the base metal (65G steel), and 1.3...1.8 times, compared to the base material. The observed changes in coatings characteristics are explained by Charpy effect, dispersion hardening and the formation of new phases in the coatings (boride eutectics).
Analysis of Galvanized Coatings Applied on General Purpose Wire
Authors: Zotov S.V.
Published: January 2020

The paper deals with applying hot-dip galvanized coatings on general purpose wire. Galvanized wire properties were generalized and structured as a hierarchical tree of properties. A set of experiments was carried out to analyze potential operation modes of the line and the application of steel wire. The coating quality forecasting technique was developed to implement a production process, ensuring the required properties of galvanized wire.
Formation of Coatings on Details from Valve Metals Alloys by Micro-Arc Oxidation in Internal Cavities of Counter Electrodes
Authors: Tchufistov Oleg
Published: January 2020

It is shown that micro-arc oxidation (MAO), implemented according to traditional schemes in electrolytic baths with mechanical and pneumatic mixers, does not provide the formation of uniform ceramic coatings on the surfaces of holes, grooves and slots in the details from the alloys of the metals of valve group, and is characterized by a significant cost and relatively low safety. Fundamental possibility of MAO realization in the inner cavities of the special counter electrodes by passing solutions of electrolytes through them is installed. The calculated and experimental researches of MAO, applied to the processing of ball details from aluminum and titanium alloys, are conducted. The most rational design parameters of counter electrodes, as well as the rational parameters of the flow of electrolyte solutions in the clearances between the surfaces of details and counter electrodes are revealed. Innovative schemes for MAO of spherical details are developed. By measuring the thickness and hardness of the formed coatings it is proved that MAO, in the internal cavities of the counter electrodes, provides for the formation of more uniform ceramic coatings on the details from alloys of valve metals, in comparison with the traditional MAO in electrolytic baths with pneumatic and mechanical mixers.
Properties of Epoxy-Diane Composites Modified by Techno-Genic Fillers
Authors: Kiryushina N.Yu. , Semeykin A.Yu.
Published: January 2020

The article proposes a method for producing epoxy polymers, based on epoxy resin ED-20, modified with slag from the JSC “Oskol Electrometallurgical Plant”. It has been established that it is possible to regulate physical and mechanical properties of composite materials by introducing filler, which will allow expanding its areas of application.
The Abrasive Properties of Coal Power Plants Ash and Slag Materials
Authors: Shcheglov Yury V. , Fedorova Natalia V. , Shaforost Dmitry A.
Published: January 2020

Ash and slag materials (ASM), formed during the combustion of coal in thermal power plants, have abrasive properties, which are manifested during the operation of boiler units, ash collection, ash and slag removal. These properties must be considered to ensure durable trouble-free operation of thermal power plants. On the other hand, these properties can be used when planning measures for ash and slag material disposal. The results of experimental-industrial tests of ash and slag materials abrasive properties are presented in this paper. It was shown that, when cleaning metal surfaces of various shapes from old paint coatings, the consumption of crushed coal slag per 1 m2 of the surface being treated is on average 4.8 times less than the consumption of sand, the time of surface treatment with slag is on average 2.45 times less than with the use of sand in similar conditions. The empirical formulas to evaluate the technical and economic efficiency of using ash and slag materials as an abrasive in industrial applications are given.
The Processing of the Profile Surface of the Work-Pieces, Characterized by Low Rigidity
Authors: Fomin Anatoly A. , Gusev Vladimir G. , Timerbaev Nail F.
Published: January 2020

This work indicates that the prediction of the geometric indicators of the quality of the machined surface in the design of technological operations for milling a profile surface of work-pieces with low rigidity is possible, on the basis of an analysis of the elastic displacements of the technological system elements, the flexural rigidity of the work-piece as a function of its initial dimensions, the locating chart and the physical and mechanical characteristics of the material being processed. The article describes the characteristics of the elements of the technological system for the profile milling of work-pieces of low rigidity; The analytical dependencies linking the elastic displacements of the work-piece during the processing of various wood species with elements of the milling mode and the design parameters of the mill are given. Extreme total elastic displacements of the technological system during the cutting process are determined. Mathematical models of the maximum geometric error of the machined surface, as a function of the work-piece's flexural rigidity and the spindle unit, are established. Based on the results of the analysis, recommendations for improving the accuracy of the product were developed.
Wear Resistance and Characteristics of the Friction Surface of Metal Coatings with Nitride-Boride Alloying
Authors: Eremin Evgeniy N. , Losev Alexsander S. , Borodikhin Sergey A.
Published: January 2020

The wear resistance and characteristics of the friction surface of metal coatings with nitride-boride alloying are investigated. The object of the study was the steel deposited with flux-cored wire containing 15% chromium, 0.5% boron nitride, 1.25% titanium di-boride and 0,5% zirconium di-boride. It was established that the average value of the relative wear per test was 0.00416 g/m, which is 1.8 times less than that of the coating metal without borides. The average value of linear wear was 0.0122 mm/m, which is 1,9 times less than that of the coating metal without borides. The average value of the friction torque for the entire friction path in 339 m was 20.96 Nm. The coefficient of friction was 0.425. The hardness of such a metal reaches a maximum value of 57 HRC. The micro-hardness of structural objects is for the matrix 617-648 HV, eutectic 764-847 HV and strengthening phases 1128-1247 HV. It is shown that the metal structure is an iron-chromium martensitic matrix with a eutectic component, formed on the basis of boride (Fe, Cr)2B and high-strength nitride ε-(Fe, Cr)2-3N, which is an effective obstacle to dislocation slip under conditions of plastic deformation of the surface at wear.
Choice of Protective Coating of Metal Molds for Casting Non-Ferrous Alloys
Authors: Gavariev Renat V. , Savin Igor A. , Soldatkina Elena N.
Published: January 2020

Features of the process of injection molding of non-ferrous metals and zinc alloys, in particular, consisting in the rate of crystallization of the process of melting, as well as cyclically repetitive temperature and shock loads of the forming surfaces of the mold, cause most defects, in which the form can be considered unfit for further use.
Morphology and Properties of Solid Chrome Plating, Obtained by the Galvano-Mechanical Method
Authors: Galimov D.M. , Ardashev Dmitry V. , Dyakonov Aleksandr A.
Published: January 2020

In this article, studies of chromium coatings obtained by a conventional electroplating method, as well as by electroplating combined with mechanical processing, were carried out. The metallographic investigations and the micro-hardness tests of the coating were carried out and characteristic types of electroplating chromium coatings were determined. It was determined that the coating obtained by galvano-mechanical processing (current density – 75 A/dm2, solution temperature – 58 °C, chrome plating time – 45 min) does not have dendritic defects, fits snugly to the base material, however, is characterized by an increased fragility. The micro-hardness of the galvanic chrome plating, obtained by electroplating, with a load of 100 g, is 960...990 HV. The surface of galvanic chromium coatings obtained under different conditions was investigated, the advantage of the galvano-mechanical technology of applying a chromium coating, implemented on the sample under study, was shown.
Wetting of Low Carbon Steel by High-Entropy Melts CuSnBiPbGa, CuSnBiPbIn and CuSnBiInCd and Formed Structure of Diffusion Layers
Authors: Chikova O.A. , Brodova Irina , Tsepelev Vladimir S. , Shmakova Ksenya Yu.
Published: January 2020

We present a result of a study of reactive wetting of surface of low carbon steel by liquid alloys CuSnBiPbGa, CuSnBiPbIn and CuSnBiInCd of equiatomic composition. Dependences of contact angle and spot diameter of wetted surface on temperature and time were studied. Liquid alloy CuSnBiPbGa begins wetting of surface of steel at 900 °C; spreading rate at higher temperatures increased by 8 times. Liquid alloy CuSnBiPbIn begins wetting surface of steel at 780°C, but spreading speed is almost unchanged with the further increase in temperature. Liquid alloy CuSnBiInCd begins wetting of surface of steel at a temperature of 570°C, and spreading is in a flash in nature. We studied microstructure and chemical composition of diffusion layers, formed at the spreading of liquid alloys of equiatomic composition CuSnBiPbGa, CuSnBiPbIn and CuSnBiInCd on steel surface. In all experiments at boundary with substrate a ductile transition layer of a solid solution of iron-based is formed. The thickness of diffusion layer side depends on the alloy composition. The widest diffusion layers formed for alloy CuSnBiInCd, and the most narrow - for alloy CuSnBiPbGa. We detected in segregations of copper and gallium atoms for bimetallic sample "CuSnBiPbGa+steel", of copper and tin atoms for samples "CuSnBiPbIn+steel" and "CuSnBiInCd+steel" in diffusion layers. The results of these studies have significance for the design of soldering technology and application of protective coatings on steel products.
Investigation of the Influence of Kinematic and Geometric Parameters of the Thermo- Sprayer Location on the Adhesion Strength of Anti-Friction Coating
Authors: Rodichev Alexey Yu. , Gryadynova Elena N. , Gorin Andrey V.
Published: January 2020

The article presents the results of the influence of the kinematic and geometric parameters of the thermos-sprayer location on the adhesion strength of the anti-friction coating. A mathematical apparatus for calculating the inertia forces acting on an anti-friction coating particle is proposed. The results of a number of experimental studies confirming the convergence of theoretical positions are presented. As a result, dependencies have been revealed that make it possible to predict the bond strength of the anti-friction coating with the steel base during gas-flame spraying.
Technologies and Materials for Boriding of Steelworks
Authors: Astashchenko V.I. , Shveyov A.I. , Shveyova T.V.
Published: January 2020

Compositions of mixes for boriding of steelworks are offered. The entered components in composition of powdery blend are proved. Results of a microstructure and hardness of the strengthened surface after boriding deformed and cast steel are given. The possibility of boriding of a surface of founding in a casting mold is shown. The frequency rate of effective use of the saturating mix in operation is defined.
Influence of Phase Composition of Steel on a Damage Rate from Bio-Corrosion
Authors: Volgina Natalya I. , Saltykova Tatyana S. , Khlamkova Svetlana S.
Published: January 2020

The complex research of influence of a structural condition of metal on resistance to corrosion destruction of the low-alloyed steel, operated in biocorrosion environments, is conducted. It is established that the ferritic component of a structure resists better in the environment modeling conditions of impact of biogenous gases on metal under the exfoliated anticorrosive covering. Ferrite – carbide mix, in the form of beynit, has a bigger resistance in the environment reproducing conditions of lack of biogenous factors. Existence in beynitny structure of a martensitic component leads to the largest resistance of biocorrosion in the environment modeling conditions of anaerobic corrosion with biogenous gases.
An Influence of EAF Dust Calcining Conditions on Zinc Leaching Efficiency in Ammonium-Chloride Media
Authors: Toporkova Yulia I. , Prodanova D.A. , Anisimova O.S.
Published: January 2020

An ammonium leaching of electric arc furnace dust (EAFD) was described in this paper. Ural steelmaking plants obtain EAFD of the following chemical composition, %: 23 Zn; 26 Fe; 10 Cl; 2,5 Ca; 2 Mg; 1,2 Pb; 1 Na. The most complete zinc extraction can be achieved with two-stages treatment by calcination of dusts [1], followed by leaching. The effect of calcination temperature (500-1000 °C), calcination time (1-4 hours) and Ca/Fe mass ratio on zinc extraction efficiency in ammonia solutions was studied. The optimal conditions were proposed to extract up to 87% zinc.
Arsenic Precipitation from Solutions in Autoclave-Hydrometallurgical Technology of Processing Sulphide Concentrates
Authors: Andreev Yury V.
Published: January 2020

Currently, the share of gold extracted from technologically simple gold ores is steadily decreasing, which determines the involvement in the processing of refractory gold ores containing finely disseminated gold and silver in sulfides, mainly in pyrites and arsenopyrites. Autoclave oxidation is a promising method of pretreatment of the refractory sulfide-arsenic gold-bearing raw materials before cyanidation. A serious problem of auriferous ores autoclave-hydrometallurgical processing is the removal of contained arsenic into relatively harmless and capable of being kept forms. This article shows the results of behavior of arsenic during the neutralization of solid after autoclave oxidative leaching of refractory gold-containing materials.
Copper Recovery from Rinse Waters after Ammoniac Etching of Printed Circuit Boards
Authors: Makovskaya Olga Yu. , Shevchuk A.P. , Sorokin S.P.
Published: January 2020

The process of sorption-electrochemical cleaning of rinse waters, obtained after ammonia etching of printed circuit boards from copper ions, is proposed. Cation exchanger KU-2×8 and ampholyte Lewatit MonoPlus TP 207 for the extraction of copper were tested. Capacity up to breakthrough of Lewatit MonoPlus TP 207 is 0.11 g/g and a full dynamic exchange capacity for copper of 0.15 g/g. Various options of a pregnant ion exchanger desorption are considered. The best stripping ability has a 20% solution of sulfuric acid. The possibility of desorption by a partially de-coppered eluate was studied. This scheme allows the use of acid formed in the process of copper electro-winning. The effect of concentrations of NH4Cl and NH4OH on the sorption of copper was studied. It was shown that, with an increase in the concentration of NH4Cl to 100 g/dm3, the capacity of the ion exchanger decreases by 10.42%. Thus, the ion exchanger Lewatit MonoPlus TP 207 effectively absorbs copper even at high salt background. A combined sorption-electrochemical technology has been proposed for treatment of rinse waters. The proposed technology will reduce consumption of fresh water and ammonia for printed circuit boards washing and extract copper in the form of elemental metal.
Does duration of stenting increase the risk of clinical infection?
Authors: Toprak Tuncay , Şahin Aytaç , Kutluhan Musab Ali , Akgul Korhan , Danacıoğlu Yavuz Onur , Ramazanoğlu Mehmet Akif , Verit Ayhan
Published: January 2020

Objective: We investigated when an indwelling ureteral catheter should be withdrawn for infection and evaluated the importance of urinary cultures in identifying colonized microorganisms and define the bacterial flora encountered in the study. Moreover, this study tried to determine the clinical role of stent culture in clinical practice. Materials and methods: The study was conducted between June 2018 and February 2019. Patients with ureteral stent implantation after endoscopic ureteral stone treatment were divided into two groups and each group consisted of 45 patients. Ureteral catheter was removed 15 and 30 days after ureteral stone treatment in group 1 and 2, respectively, and transferred for microbiological examination. The urine culture was obtained before and after ureteral stent implantation. The groups were compared in terms of demographics, urine and catheter cultures results. Urine analysis and catheter culture results were also compared. Results: Demographic data of patients were similar in both groups. 3 patients in group 1 and 12 patients in group 2 had positive urine culture before catheter retraction; 2 of 45 and 6 of 45 patients had positive catheter culture in group 1 and 2, respectively. Although 2 patients in group 1 and 4 patients in group 2 had urine culture sterile, they had growth in catheter culture. In Group 1, 1 of the microorganisms was E. fecalis and 1 was E. coli. In Group 2, 2 cases were E. fecalis, 3 were E. coli and 1 was MRSE. There was no significant difference between the urine analysis results of the patients before catheter retraction and catheter culture positivity. Conclusions: Pre-operative urine culture does not exclude catheter colonization, and the prolonged duration of the catheter associated with greater colonization and may be associated urinary tract infection. Ureteral catheter should be removed as early as possible.
Solitary prostatic cancer metastasis to the testis: A case report and lessons to learn
Authors: Ismail Asmaa , Elmansy Hazem , Shahrour Walid , Prowse Owen , Kotb Ahmed
Published: January 2020

Prostate cancer (Pca) is a complex disease. Several case series and reports have described the spread of Pca to unusual organs, like esophagus, eye and periureteric fat causing ureteropelvic junction obstruction. Spread of Pca to the testis has been reported in few case reports, however Pca was always firstly diagnosed in all published cases and testicular spread of cancer has been diagnosed during follow up of the patients. This case is unique in that, the patient initially presented with a testicular mass and histologic examination after orchiectomy allowed to diagnose prostatic cancer. This patient was 81 years old and he never had PSA screening by his family doctor. PSA was not even done initially by us considering his age and the presentation with testicular mass. This case may impact clinical practice in several ways: 1) considering Pca always in the differential diagnosis of any disease of an adult man, regardless of its presentation because we did not do that at initial patient evaluation and PSA was only measured after orchiectomy when pathology demonstrated metastatic Pca; 2) suggesting standard orchiectomy with epididemectomy for surgical castration instead of the current surgical technique of subcapsular/subepididymal orchiectomy, because our patient had cancer involving his epididymis as well; 3) suggesting to include PSMA as a part of preoperative staging for high risk Pca patients, in consideration that PSMA is proving to be a promising new imaging technique that can help diagnosing metastatic Pca in unusual locations.
Right open nephrectomy under combined spinal and peridural operative anesthesia and analgesia (CSE): A new anesthetic approach in abdominal surgery
Authors: Cotugno Michele , Dallaglio Matteo , Cantadori Luca , Villani Fabio , Martens Daniel , Cantoni Federico , Potenzoni Michele , Micali Salvatore , Rocco M.C. Bernardo , Prati Andrea
Published: January 2020

A case of right open nephrectomy performed under combined spinal and epidural anesthesia and analgesia was presented. This new anesthetic technique gives significant advantages to the patient by avoiding endotracheal intubation with mechanical ventilation and curare administration and by reducing the use of opioids.
Prognostic value of epidermal growth factor receptor expression in operable non-small cell lung carcinoma
Authors: Seyhan Ekrem Cengiz , Altın Sedat , Çetinkaya Erdogan , Sökücü Sinem , Abalı Hülya , Buyukpinarbasili Nur , Fener Neslihan
Published: January 2020

Background and aim: Increased expression of the epidermal growth factor receptor (EGFR) in non-small cell lung cancer (NSCLC), supporting the tumor growth by a possible endocrine mechanism, affects patient survival negatively. We designed a study to test EGFR expression by immunohisto- chemistry (IHC) in resected stage I–II NSCLC and to correlate its overexpression with survival.

Methods: EGFR expression was evaluated in 98 consecutive NSCLC patients after complete resection (53 squamous cell carcinomas, 40 adenocarcinomas, 5 large cell carcinomas: stage I, 57 (58%) and stage II, 41 (42%). IHC was used to examine the expression of EGFR in resected lung tumor sam- ples obtained from these patients, who had no pre- or post- operative chemotherapy or radiotherapy. Univariate and multivariate analyses were performed for factors influencing patient survival.

Results: EGFR was expressed in 51 (52%) of 98 NSCLC sam- ples. More squamous tumors (61%) were EGFR-positive than adenocarcinomas (38%) (p = 0.038). There was a statistically significant correlation between EGFR expression and stage (p = 0.04). No difference was found between EGFR positive and negative tumors in the 5-year overall survival (57% vs. 73%, p = 0.13).

Conclusion: The level of EGFR expression in tumors was not a successful predictor of survival in resected NSCLC.
Methotrexate-induced pneumonitis in Crohn’s disease
Authors: D'Andrea Nadia , Triolo Luca , Margagnoni Giovanna , Aratari Annalisa , Sanguinetti Claudio M.
Published: January 2020

Methotrexate (MTX) is a folate-antagonist used in several neoplastic and inflammatory diseases. Reports of pulmonary complications in patients given low-dose MTX therapy are increasing. Pulmonary toxicity from MTX has a variable fre- quency and can present with different forms. Most often MTX-induced pneumonia in patients affected by rheumatoid arthritis (RA) is reported. In this paper we describe a case of MTX-related pneumonitis in a relatively young woman affected by Crohn's disease who presented non-productive cough, fever and dyspnea on exer- cise. Chest X-ray demonstrated bilateral interstitial infil- trates and at computed tomography (CT) ground-glass opac- ities appeared in both lungs. At spirometry an obstructive defect was demonstrated. A rapid improvement of symptoms and the regression of radiographic and spirometric alter- ations was achieved through MTX withdrawal and the intro- duction of corticosteroid therapy.
At home with pulmonary rehabilitation
Authors: ZuWallack Richard
Published: January 2020

Pulmonary rehabilitation results in substantial and clinically meaningful improvements in dyspnea, exercise capacity and quality of life for patients with chronic respiratory diseases such as COPD.  There is also evidence indicating that pulmonary re- habilitation reduces subsequent health care utilization and – perhaps – mortality, if the intervention is given in the post-exacerbation period.
Women, immigration, poverty and tuberculosis
Authors: Casali Lucio , Crapa Mariano E.
Published: January 2020

In December 2009 an information sheet edited by WHO reported that, in 2008, 3.6 million women fell ill with tuberculosis (TB) and 700,000 women died from TB, including 200,000 with human immunodeficiency virus (HIV) and TB. TB is the 3rd leading cause of death worldwide among women aged between 15 and 44 years. It should be noted that this range englobes both the reproductive and working age. TB is the 4th leading cause of death among women aged 10-19 years in low income countries. Once infected, women of reproductive age are more susceptible to developing TB than men of the same age...
Deficits in postural control in individuals with COPD - emerging evidence for an important secondary impairment
Authors: Beauchamp Maria K. , Brooks Dina , Goldstein Roger
Published: January 2020

Emerging evidence suggests that individuals with COPD demonstrate reductions in balance control that may be associated with an increased fall risk. The purpose of this review is to: 1) provide a brief overview of balance control and its assessment; 2) review relevant literature describing balance impairment in individuals with COPD; and 3) highlight impor- tant areas for future research. The observation of balance deficits and an increased fall risk in patients with COPD suggests the need for including balance assessment and training for patients enrolled in pulmonary rehabilitation who may be vulnerable. Further studies are needed to determine which aspects of balance are affected and to examine the impact of interventions.
Evaluating simulated compact polarimetry for Emergency Geomatics Service flood mapping
Authors: Rainville T , Olthof I
Published: January 2020

When severe flooding occurs in Canada, the Emergency Geomatics Service (EGS) is tasked with creating and disseminating maps that depict the flood extent in near real time. These maps delineate open water and flooded vegetation and are created using a combination
of raster image processing, machine learning classification, and threshold-based region growing. The predominant data source used to create these maps is synthetic aperture radar (SAR) imagery from RADARSAT-2 (R2). With the commissioning phase of the RADARSAT Constellation Mission (RCM) nearing
completion, the EGS must adapt its methods for use with what is expected to be the EGS's new default source of SAR data. The introduction of RCM's circular-transmit linear-receive (CTLR) beam mode provides the option to exploit compact polarimetric (CP) information not previously available through
R2. The aim of this study is to determine the most effective CP parameters for use in mapping open water and flooded vegetation by applying current EGS methodologies, as well as to assess the quality of these products in comparison to products created using R2 data. Nineteen quad-polarization R2
scenes selected from three regions prone to springtime flooding were used to create reference flood maps using current EGS methodologies. These scenes were also used to simulate RCM CP data that included 22 parameters at three different noise floors and spatial resolutions representative of three
RCM beam modes. Using a multi-criteria ranking procedure, CP parameters were ranked in order of importance and entered into a stepwise classification procedure for evaluation against reference R2 products. Results suggest the top four CP parameters - m-chi-volume or m-delta-volume, RR intensity,
Shannon Entropy intensity (SEi), and RV intensity - achieved a minimum omission and commission, and maximum agreement with baseline R2 products when evaluated across all 19 scenes and three beam modes. Separability analyses between manually delineated flooded vegetation polygons and other land cover
classes identified four candidate CP parameters - RH intensity, RR intensity, SEi, and the first Stokes parameter (SV0) - suitable for threshold-based flooded vegetation region growing. Region growing thresholds based on CP values beneath flooded vegetation polygons were found to be dependent on
incidence angle for each of these four parameters. After region growing flooded vegetation using established threshold values for each of the four candidate CP parameters, results were evaluated against flooded vegetation polygons to assess omission error, and against upland land cover to assess
commission error, wherein RH intensity was deemed best to map flooded vegetation. The results of the study are a set of suitable CP parameters to generate flood maps from RCM data using current EGS methodologies that must be verified and validated further once real RCM data become
available.
The attitude of the medical profession to chiropractic
Authors: De Klerk J. N.
Published: January 2020

No abstract available.
South African sports association for paraplegics and other physically disabled
Authors: Barrish Menzo
Published: January 2020

Sport vir gestremdes staan onder beheer van die Suid- Afrikaanse Sport Assosiasie vir Parapleë en Ander Liggaamlik gestremdes. Sport soorte ingesluit word genoem, die geskiedenis van sport vir gestremdes word kortliks geskets en die prestasies van Suid-Afrikaanse sportlui op die gebied word bespreek. Kompetisie met normale sportlui vind nou ook plaas.
Classification in sport for the disabled
Authors: Van Rensburg C. K.
Published: January 2020

Die doel van klassifikasie is om regverdige kompetisie aan almal te verskaf. Dit varieer van eenvoudig tot baie ingewikkeld en word gedurig hersien en verander. Die hersiene klassifikasie, gebaseer op neurologiese ondersoek, word beskryf.
Editorial
Authors: Irwin-Carruthers S. H.
Published: January 2020

No abstract available.
Sport and the child with a learning disability
Authors: Van der Merwe G. D.
Published: January 2020

Die kind met leergestremdheid, uiteenlopend van aard, vind deelname aan sport dikwels moeilik. Dit kan egter sy lewenservaring verbreed mits dit binne sy persoonsmoontlikhede geskied. Finaliteit oor die besonderhede van deelname moet nog bereik word.
Book reviews
Authors: Office Editorial
Published: January 2020

No abstract available.
Mrs Molly Levy: President South African Society of Physiotherapy
Authors: Office Editorial
Published: January 2020

No absract available.
The neurosurgeon and chronic pain
Authors: De Villiers J. C.
Published: January 2020

No abstract available.
Report on the 13th General Meeting of the National Council
Authors: Irwin-Carruthers S. H.
Published: January 2020

No abstract available.
Ethics in human experimentation
Authors: Beenhakker J. C.
Published: January 2020

No abstract available.
Some advances in perinatal care
Authors: Coetzee E. J.
Published: January 2020

No abstract available.
Leitura e ensino: por avaliações que levem (mesmo) os ambientes digitais em consideração
Authors: Coscarelli Carla Viana , Ribeiro Ana Elisa
Published: January 2020

Neste artigo discutimos diferentes matrizes de habilidade de avaliações de leitura em larga escala e como elas incorporam questões relativas ao letramento digital. Analisamos as matrizes de avaliações de leitura no Brasil como o Saeb e o Enem, assim como as habilidades de leitura verificadas em avaliações internacionais como o Pisa, que incorpora a leitura online. Além disso, analisamos as habilidades de leitura elencadas pelo ISTE, que, por sua vez, percebe o ato de leitura como sendo parte de um processo de pesquisa e de solução de problemas. Analisamos também a matriz de letramento digital desenvolvida por Dias e Novais e que tem sido tomada como referência para muitas pesquisas. Finalizamos esse texto mostrando que matrizes de letramento precisam ser construídas, avaliadas e reformuladas sempre pelos educadores, a fim de atender às demandas específicas de cada escola e cada comunidade escolar.