Investigation into the question of complex processing of bauxites of the srednetimanskoe deposit

A new technology of processing raw materials with the use of active alkali is suggested for bauxites of the Srednetimanskoe deposit; bauxite is opened at 300°C for 1 h. This technology makes it possible to increase the recovery of alumina to 94-98% and obtain red slimes and zeolite enriched with iron (58%) and titanium (4.8%); the environmental problem of storing red slimes is resolved. The blast-furnace smelting of such slimes makes it possible to obtain naturally doped cast iron and slag enriched with titanium and rare earth metals. When purifying (desiliconizing) the aluminate solution, a valuable product-sodium aluminum silicate hydrate of the zeolite type-is incidentally obtained. © 2013 Allerton Press, Inc

Obtaining of Maghemite Containing Red Mud for Effective As(V) Adsorption

This paper describes the studies of the use of red muds as adsorbents for cleaning solutions from As(V). The red mud is a waste that contains a large amount of iron oxides and hydroxides, which are excellent adsorbents of arsenic, especially those possessing magnetic properties and large specific surface area. The purpose of the experiment was to study the possibility of obtaining an effective adsorbent by direct extraction of alumina from bauxite using the caustic alkali fusion method and optimization of the process. The main iron-containing phase of the red muds obtained by fusing bauxite with caustic alkali was maghemite, which has a large specific surface area. Arsenic adsorption experiments were carried out using red muds obtained through bauxite alkali fusing at different temperatures and time of fusion, as well as the mass ratio of caustic alkali to bauxite. The red muds obtained by fusing bauxite with caustic alkali at 400∘ C and NaOH to bauxite mass ration 1.5 within 70 minutes have the highest effectiveness removing arsenic. Their As(V) uptake capacity was over than 37 mg/g. Keywords: red mud, maghemite, nanoparticles, As(V) adsorption, optimizatio

Evaluation of the microstructure and mechanical properties of a new modified cast and laser-melted AA7075 alloy

The mechanical properties and microstructure of as-cast and homogenized AA7075 were investigated. This alloy was modified by adding transition elements 0.3%Sc + 0.5%Zr, 1%Ti + 0.2%B, and 1%Fe + 1%Ni for use in additive manufacturing applications. After adding Ti + B and Sc + Zr, the structure became uniform and finer with the formation of the Al3(Sc, Zr) and TiB2 phases. Coarse structures were obtained with the formation of an extremely unfavorable morphology, close to a needle-like structure when Fe + Ni was added. The mechanical properties of the modified alloys were increased compared to those of the standard alloy, where the best ultimate tensile strength (UTS) and yield strength (YS) were obtained in the AA7075-TiB alloy compared to the standard alloy in as-cast and homogenized conditions, and the highest hardness value was provided by Fe + Ni additives. The effect of the laser melting process on the microstructure and mechanical properties was investigated. Single laser melts were performed on these alloys using 330 V and a scanning speed of 8 mm/s. During the laser melting, the liquation of the alloying elements occurred due to non-equilibrium solidification. A change in the microstructures was observed within the melt zone and heat-affected zone (HAZ). The hardness of the laser-melted zone (LMZ) after adding the modification elements was increased in comparison with that of the standard alloy. Corrosion testing was performed using a solution of 100 mL distilled water, 3.1 g NaCl, and 1 mL HCl over 5, 10, and 30 min and 1 and 2 h. The corrosion resistance of the alloy modified with FeNi was low because of the non-uniform elemental distribution along the LMZ, but in the case of modification with ScZr and TiB, the corrosion resistance was better compared to that of the standard alloy. © 2019 by the authors.Ministry of Science and Higher Education of the Russian FederationThe author (Asmaa M. Khalil) gratefully acknowledges financial support from the Ministry of Science and Higher Education of the Russian Federation in the framework of Increase Competitiveness Program of MISiS (Support project for young research engineers)

Models for development of the information-control complex of the enterprise

This article provides a brief analysis of the development of concepts and terms used in the automation the processes of production and enterprise management. The conclusion is made about the preference of the term “information-control complex” (ICC) of the enterprise and the expediency of using various concepts in its creation. A model for the development of ICC is proposed, based on the definition of a system that implements the system-target approach, and the “engineering” concept

Obtaining of Pigment-Quality Magnetite from Sintering Process Red Mud

The limited availability of high-quality bauxite and, at the same time, the formation of a considerable amount of harmful red mud (bauxite residue) causes to develop cost-effective technologies for bauxite processing. Selective separation of iron from red mud allows solving this problem and producing marketable products in the form of pigment-quality magnetite. In this context, the possibility of the pigment-quality magnetite obtaining by the interaction of freshly precipitated iron hydroxide (III) of the sintering process red mud with ferrous iron ions in an alkaline medium is studied. It was found that the optimal parameters of the process are: temperature = 90 C; duration = 4 hours; a ratio of ferrous iron to stoichiometric quantity = 70 %. The yield of the magnetic concentrate under optimal conditions was 69.3 %, and the content of magnetite in concentrate was 47.7 %. © Published under licence by IOP Publishing Ltd

Development of the optimal mode of bleaching of linen materials by periodic method

The article presents the results of research on the operational properties of linen material bleached by the developed combined periodic method. The influence of the composition and concentration of components in the working solution on the quality indicators of bleaching was studied. The results of the study show that the use of the proposed combined method for bleaching linen and mixed fabrics allows you to obtain high values of the degree of whiteness and capillarity with the preservation of strength indicators and minimal destruction of cellulose fiber

THE USE OF NEW REAGENT KITS FOR DETECTION AND DESCRIPTION OF ADDITIONAL ALLELES

During the screening typing of recruited volunteers with Volga Federal District for unrelated hematopoietic stem cell registry on the loci (HLA)-A, B, DRB1, DRB345 in sample No 1758 identified a new allele at locus A. The use of basic kit AlleleSEQR HLA-A Sequencing in combination with HARP – A2F98A allowed to determine the genotype of this sample – А*30:01:01, a new allele А*25, В*13, 44, DRB1*03, 09, DRB3*02, DRB4*01

The role of iron metabolism indicators in predicting gestational diabetes mellitus

Iron (Fe) deficiency and hyperglycaemia are both widely found throughout the world among pregnant women. According to the latest data from the American Diabetes Association (ADA), the prevalence of gestational diabetes mellitus (GDM) has increased and reaches 15–20%. Nowadays, there is growing evidence that a link between Fe metabolism and glucose homeostasis exists. The study of changes in the indicators of Fe metabolism in the serum of pregnant women with glucose intolerance and GDM plays an important role in expanding the understanding of the pathogenesis of these conditions. The hypothesis that excess Fe increases the risk of developing GDM has prompted us to review and evaluate the potential relationship between elevated Fe levels and the risk of developing GDM. The aim is to integrate all available data on the correlation between GDM and Fe status in the body. It is increasingly being recognised that excess Fe accumulation in the body is associated with an increased risk of diabetes. There is no available data on the relationship between serum ferritin and GDM in the Russian population, while early identification of the risk of GDM development will be of great importance for its related health effects and prevention. The role of Fe status as a GDM biomarker in high-risk populations is of interest, both for prognostic and diagnostic measures, and for therapeutic interventions. For a better understanding of whether an excess of Fe increases the risk of developing GDM, studies are needed to reveal the role of Fe in the mechanisms of GDM development

Models and automation technologies for the curriculum development

The aim of the research was to determine the sequence of the curriculum development stages on the basis of the system analysis, as well as to create models and information technologies for the implementation of thesestages.The methods and the models of the systems’ theory and the system analysis, including methods and automated procedures for structuring organizational aims, models and automated procedures for organizing complex expertise.On the basis of the analysis of existing studies in the field of curriculum modeling, using formal mathematical language, including optimization models, that help to make distribution of disciplines by years and semesters in accordance with the relevant restrictions, it is shown, that the complexity and dimension of these tasks require the development of special software; the problem of defining the input data and restrictions requires a large time investment, that seems to be difficult to provide in real conditions of plans’ developing, thus it is almost impossible to verify the objectivity of the input data and the restrictions in such models. For a complete analysis of the process of curriculum development it is proposed to use the system definition, based on the system-targeted approach. On the basis of this definition the reasonable sequence of the integrated stages for the development of the curriculum was justified: 1) definition (specification) of the requirements for the educational content; 2) determining the number of subjects, included in the curriculum; 3) definition of the sequence of the subjects; 4) distribution of subjects by semesters. The models and technologies for the implementation of these stages of curriculum development were given in the article: 1) models, based on the information approach of A.Denisov and the modified degree of compliance with objectives based on Denisov’s evaluation index (in the article the idea of evaluating the degree of the impact of disciplines for realization of competences was used); 2) models to define the sequence of subjects from curriculum: a) the models, based on evaluating the relationship between the disciplines, using simplicial complex theory, b) the models, implemented by means of information search, using the information retrieval language with the grammar, containing the system of predicates. To implement the models, the automated dialogue procedures were developed.Models have been tested during the process of the development and the adjustment of the working curriculum for bachelor’s and master’s degree programs in the fields «System Analysis and Management», «Information Systems and Technologies», «Applied Informatics»

Investigation of influence of parameters of laser welding on microstructure and mechanical properties of Al-4.7%Mg -0.32%Mn-0.21%Sc-0.09%Zr alloy

В работе исследовано влияние пиковой мощности (0,64–1,31 кВт) при напряжениях из диапазона 330–430 В при лазерной сварке со стандартным диаметром пучка и длительностью импульса 8 мс. Изучена микроструктура, сформированная сваркой. Установлено, что существует разноообразие в размерах и форме зерен в зоне шва. Показано, что с увеличением пиковой мощности ширина и глубина области шва увеличивается.In the present work the influence of peak power of laser beam welding were studied at voltage range from 330 to 430 V and peak power (0,64; 0,75; 0,87; 1,01; 1,15; 1,31) kW , and laser beam diameter is standard and duration 8 ms. The microstructure after welding was studied. It was concluded that there is a variant in grain size and shape in the welded zone and pre-welded area. The dimensions of welded zone was measured. From measuring data, it was observed, that as increasing the peak power the width and depth of welding increased.The work was performed as part of the state work "Carrying out of research work (basic research, applied research and experimental development)" state task MES of Russia in the sphere of scientific activities 2014–2016. (Task № 2014/113)