The effect of cross rolling on the microstructure of ferrous and non-ferrous metals and alloys

The cross rolling is the one of most perspective method of refinement microstructure metals by severe plastic deformation method. This method gives ability to get the long length billets. However, deformation and trajectories of the metal is very heterogeneous across the section of the rolled piece. This paper presents the finite element method (FEM) simulation of hot cross rolling and experimental study of the effect of the cross rolling on a different threeroll mills on the microstructure of ordinary structural alloy steel, stainless steel and technical copper in different zones of the bar. Analysis showed significant structure refinement in all cases. The best result was achieved on the stainless steel, and shown the formation of equal-axis ultra-fine-grain structure on the bar periphery

Synthesis and Electrochemical Behavior of the Molybdenum- Modified Electrode Based on Rice Husk

The article presents the results of electrochemical studies made on carbon paste electrode based on bisorbents powder modified by molybdenum. Bisorbent consists of carbon and SiO2. It was synthesized as a support structure obtained from rice husk thermal decomposition products. The obtained sorption material has surface with high specific area – 200 m2/g. Bisorbent was further modified by (NH4)6Mo7O24 · 4H2O (10 wt.%). The elemental composition of used RH was also determined. The surface morphology of plain and modified BS samples was studied. Recording of voltammetric curves was carried out at рН = 3.80, рН = 6.40 in 0.2 М electrolyte solution of Li2SO4. Cathodic and anodic waves were obtained which related to oxidation and reduction processes of molebdenium compounds in the entire range of the potentials (0.8 ÷ -1.2 V). The range of changing molybdate ions concentrations in solution was 2·10‒4 ÷ 10‒2 M. The dependencies of kinetic and electrochemical parameters on paramolybdate ions concentration were studied for modified electrode. Nature of changes in molybdenum reduction currents and oxidation currents indicates that Mo+6 reduction may occur by different mechanisms depending on the composite electrode properties. Results showed the possibility of further the synthesized composite system use for voltammetric determination of low (10‒4–10‒2) concentrations of Mo7O6-24 ions in a solution

Accesul chirurgical în tratamentul bolnavului cu traumatism asociat al complexului zigomatic

Sialolitiaza reprezintă una dintre cele mai răspândite afecţiuni ale glandelor salivare. Megasialolitiaza este extrem de rară, în literatura de specialitate fi ind descrise doar cazuri clinice şi serii de cazuri clinice, iar tratamentul optim este controversat. Autorii prezintă revista literaturii la acest subiect şi experienţa Clinicii de Chirurgie Oro-Maxilo-Facială

Youth Migration in the Conditions of the Regional Labour Market (On the Materials of the Omsk Region)

Современная социально-экономическая политика приводит к формированию устойчивых траекторий оттока населения из Сибири в центральные регионы. Омская область, являясь приграничной, выступает центром притяжения для трудовых мигрантов из Средней Азии, в частности из Казахстана, Кыргызстана, Узбекистана и др. Процессы, связанные с приездом трудовых мигрантов, достаточно освещены в научных исследованиях, в той или иной степени учтены в реализуемых программах развития региона. Но в последние годы в Омской области появились новые тенденции, связанные с усилением оттока коренного населения. Целью данного исследования является анализ молодежной миграции в Омской области в условиях регионального рынка труда. В качестве гипотезы исследования можно предположить следующее: одной из основных причин переезда молодых людей является желание найти более привлекательную работу, что связано с состоянием регионального рынка труда. В исследовании предпринят комплексный анализ проблематики, учитывающий миграционные установки населения г. Омска в возрасте 20-29 лет, а также факторы и предпосылки миграции. Эмпирическую базу исследования составили региональные статистические данные по Омской области за 2010-2017 гг., анализ данных запросов «Google Тренды», а также материалы социологического опроса выпускников вузов. Произведен сравнительный анализ численности и динамики миграции населения г. Омска в возрасте 20-29 лет. По результатам использования обоснованного социологического инструментария определены миграционные установки молодежи, а также формирующие их факторы. Сделаны выводы, согласно которым, у молодых людей сложилось субъективное негативное восприятие экономической жизни в регионе, способствующее появлению миграционных установок и ожиданий.The current situation of economic and social policies has led to the formation of stable trajectories of outflows in the central regions. The Omsk Region, situated on the border, attracts labour migrants from Central Asia, namely Kazakhstan, Kyrgyzstan, and Uzbekistan among others. The social research covers the migration processes associated with the arrival of labour migrants, and the regional development programmes account for them (to some extent). Yet, in the recent years in the Omsk Region, there are new trends related to strengthening the outflow of the native population. This study aims to analyse the youth migration in the Omsk Region in terms of the regional labour market. The authors rely on the hypothesis that one of the main reasons for young people to move is their desire to find more attractive work; this refers to the state of the regional labour market. This paper provides a comprehensive analysis of the issues, taking into account the migration of the Omsk population aged 20-29, as well as the factors affecting the migration. The study’s empirical base consists of regional statistics for 2010-2017, data analysis queries, Google trends, and the materials of graduates’ sociological surveys. The result of this is the comparative analysis of population dynamics and migration of population 20-29 y. o. in the city of Omsk. This allowed identifying the migration of young people and the relevant factors. The authors conclude that the young population have a subjectively negative perception of the region’s economic life, which contributes to the emergence of migration attitudes and expectations among them

The effect of cross rolling on the microstructure of ferrous and non-ferrous metals and alloys

The cross rolling is the one of most perspective method of refinement microstructure metals by severe plastic deformation method. This method gives ability to get the long length billets. However, deformation and trajectories of the metal is very heterogeneous across the section of the rolled piece. This paper presents the finite element method (FEM) simulation of hot cross rolling and experimental study of the effect of the cross rolling on a different threeroll mills on the microstructure of ordinary structural alloy steel, stainless steel and technical copper in different zones of the bar. Analysis showed significant structure refinement in all cases. The best result was achieved on the stainless steel, and shown the formation of equal-axis ultra-fine-grain structure on the bar periphery

COMBINING IMAGING FLOW CYTOMETRY AND MOLECULAR BIOLOGICAL METHODS TO REVEAL PRESENCE OF POTENTIALLY TOXIC ALGAE AT THE URAL RIVER IN KAZAKHSTAN

Algal blooms occur in freshwater bodies throughout the world, often leading to fish kills. Cases of these kills along the Ural River were reported in 2018–2019, involving significant amount of sturgeon in fish farming areas. In this study, the analysis of algal samples from the delta of the Ural River up to 100 km inland was carried out from August to December 2019 using imaging flow cytometry (IFC), molecular biological, and microscopic techniques. We identified the filamentous cyanobacteria Cuspidothrix issatschenkoi, Dolichospermum cf. flos-aquae, Dolichospermum cf. macrosporum, Pseudanabaena limnetica, and Planktothrix spp. as the dominant potentially toxic phytoplankton species, and we also found minor quantities of Cylindrospermopsis raciborskii. For the first time, molecular phylogenetic investigations of field clones of cyanobacteria from Ural River were carried out to establish the taxa of the dominant species and to identify the presence of genes encoding toxins. The complementary analysis with nanopore-based next-generation sequencing overlapped with the results of IFC and was instrumental in revealing minor cyanobacteria taxa. Real-time PCR analysis and sequencing indicated the presence of Microcystis and ADA-clade spp. as well as genes associated with the production of microcystin (mcyE) and the algal neurotoxin saxitoxin (sxtA) originating from cyanobacteria. These findings suggest that toxin-producing cyanobacteria could become a threat in the Ural River near Atyrau, which can significantly affect aquaculture in the region

Innovation in hospitals: a survey of the literature

Innovation, Hospitals, Survey, O3, I1,