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Potentiodynamic Study of the Anodic Behavior of Zn5Al Alloy Doped with Manganese
In: Izvestiya of Altai State University, Heft 4(114), S. 53-58
ISSN: 1561-9451
The widespread use of zinc-aluminum alloys as protective coatings for structures, products, and structures requires studying the effect of various additives in such alloys on their corrosion resistance in various environments. In studying the anode behavior of alloys, potentiodynamic methods are widely used to select methods of protection and increase the stability of anode alloys under given operating conditions. The article presents the results of a potentiodynamic study of the corrosion-electrochemical behavior of Zn5Al alloys doped with manganese in various electrolytes. An increase in the manganese concentration within the studied concentrations leads to a shift in the standard potential and pitting potential to a positive region compared to the initial Zn5Al alloy, which indicates a decrease in the corrosion rate of the studied alloys by 2-2.5 times with respect to the base alloy. An increase in the concentration of chloride ions in the electrolyte leads to a decrease in the electrochemical potentials of corrosion and pitting formation of alloys, which indicates an increase in their anode stability. An increase in the anode stability of the protective coatings of alloys depends on the time spent in an aggressive environment: the longer the time, the lower the rate of anode dissolution.
COMPLEX REAGENTS BASED ON INDUSTRIAL CONCENTRATES AROMATIC HYDROCARBONS FOR THE FLOTATION OF HIGH-ASH COALS
In: Oil and gas business: Neftegazovoe delo, Heft 6, S. 414-430
ISSN: 1813-503X
The Social Policy of Tajikistan in a Transition Economy
In: Sociological research, Band 42, Heft 4, S. 6-37
ISSN: 2328-5184
On eigenvalue problem of the Laplace operators for ellipsoidal areas
In: Uzbek Mathematical Journal, Band 2018, Heft 1, S. 146-154
SPECIFIC CARBON DIOXIDE EMISSIONS OF INDIVIDUAL HYDROCARBONS IN MOTOR FUELS
In: Oil and gas business: Neftegazovoe delo, Heft 3, S. 191-205
ISSN: 1813-503X
The increase in greenhouse gases in the atmosphere is considered to be one of the global problems of our time, as this phenomenon leads to an increase in ambient temperature. The international community tries to take various measures to reduce greenhouse gas emissions. Within the framework of the UN Framework Convention on Climate Change, the Paris Agreement was adopted in 2015, aimed at reducing greenhouse gas emissions and limiting global temperature increases. In 2016 Russia joined the Paris Agreement on Climate and committed to reduce greenhouse gas emissions by 25–30 % since 1990 levels by 2030. Transport is and will remain one of the main emitters of carbon dioxide emissions in the medium term. CO2 emissions from the combustion of any fuel depend primarily on its chemical composition. The composition of modern motor fuels includes paraffin, naphthenic, olefin and aromatic hydrocarbons, and sometimes oxygen-containing compounds are introduced into their composition. The article presents for the first time the results of studies of specific CO2 emissions of various classes of hydrocarbons included in motor fuels, depending on the number of carbon atoms in the molecule. It is shown that the specific CO2 emissions of hydrocarbons included in the composition of motor fuels differ greatly both in group composition and within groups themselves. Specific CO2 emissions of such high-octane components of automobile gasoline as butanes and toluene, for example, differ by 10.6 %, and in terms of unit of energy released – by more than 24 %.
EFFICIENCY OF VISBREAKING AND DEASPHALTING UNITS DURING THE PLANT OPERATION ACCORDING TO «FUEL OIL» AND «FUEL OIL FREE» SCHEMES
In: Oil and gas business: Neftegazovoe delo, Heft 1, S. 159
ISSN: 1813-503X
Foreign Policy Priorities of the Republic of Uzbekistan
In: Russia and New States of Eurasia, Heft 1, S. 111-123
OBTAINING PROMISING OXYGEN-CONTAINING COMPONENTS OF MOTOR FUELS
In: Oil and gas business: Neftegazovoe delo, Heft 3, S. 164
ISSN: 1813-503X
QUALITATIVE ASSESSMENT OF HEAVY OIL RESIDUES AS POTENTIAL RAW MATERIALS OF DELAYED COKING PLANTS
In: Oil and gas business: Neftegazovoe delo, Heft 2, S. 185-203
ISSN: 1813-503X
The need to increase the depth of processing of petroleum and hydrocarbon-containing raw materials entails the need for qualified processing of residual products in order to use them more efficiently. This paper shows the role of the delayed coking unit in the processing of heavy oil residues and the deepening of oil refining, as well as the state of the global and Russian market for coke production and consumption. The analysis of various heavy oil residues according to the initial physico-chemical characteristics is carried out. The material balances of coking at the laboratory installation of both individual heavy oil residues and raw mixtures have been compiled. Graphical dependences of the output of coking products on the ratio of the initial components of raw materials are established and constructed. A number of promising areas of research for further improvement of the process are identified. The obtained data can be used in production planning in order to select the optimal composition of the raw material pool, the raw materials of the refinery as a whole, and the quality requirements of the products obtained.
Central Asia and the Struggle for Soviet Legacy
In: Russia in global affairs, Band 21, Heft 2, S. 131-140
The paper discusses the "struggle for Soviet legacy' as a key concept for understanding relations in Central Asia. This struggle is a path of dependent development, in which the resources and values created in Soviet times determine interstate relations in the 21st century. The authors argue that in Central Asia this legacy rests mostly on the mega industries created during the Soviet era, and national resources and practices of their distribution. The paper concludes that in fact the struggle for Soviet legacy means confrontation over the contours of new geoeconomics in Asia.
Laboratory capability and surveillance testing for Middle East respiratory syndrome coronavirus infection in the WHO European Region, June 2013
Since September 2012, over 90 cases of respiratory disease caused by a novel coronavirus, now named Middle East respiratory syndrome coronavirus (MERS-CoV), have been reported in the Middle East and Europe. To ascertain the capabilities and testing experience of national reference laboratories across the World Health Organization (WHO) European Region to detect this virus, the European Centre for Disease Prevention and Control (ECDC) and the WHO Regional Office for Europe conducted a joint survey in November 2012 and a follow-up survey in June 2013. In 2013, 29 of 52 responding WHO European Region countries and 24 of 31 countries of the European Union/European Economic Area (EU/EEA) had laboratory capabilities to detect and confirm MERS-CoV cases, compared with 22 of 46 and 18 of 30 countries, respectively, in 2012. By June 2013, more than 2,300 patients had been tested in 23 countries in the WHO European Region with nine laboratory-confirmed MERS-CoV cases. These data indicate that the Region has developed significant capability to detect this emerging virus in accordance with WHO and ECDC guidance. However, not all countries had developed capabilities, and the needs to do so should be addressed. This includes enhancing collaborations between countries to ensure diagnostic capabilities for surveillance of MERS-CoV infections across the European Region. ; peer-reviewed
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Multiwavelength behaviour of the blazar 3C 279: Decade-long study from γ -ray to radio
We report the results of decade-long (2008-2018) γ -ray to 1 GHz radio monitoring of the blazar 3C 279, including GASP/WEBT, Fermi and Swift data, as well as polarimetric and spectroscopic data. The X-ray and γ -ray light curves correlate well, with no delay ≳ 3 h, implying general cospatiality of the emission regions. The γ -ray-optical flux-flux relation changes with activity state, ranging from a linear to amore complex dependence. The behaviour of the Stokes parameters at optical and radio wavelengths, including 43 GHz Very Long Baseline Array images, supports either a predominantly helical magnetic field or motion of the radiating plasma along a spiral path. Apparent speeds of emission knots range from 10 to 37c, with the highest values requiring bulk Lorentz factors close to those needed to explain γ -ray variability on very short time-scales. The MgII emission line flux in the 'blue' and 'red' wings correlates with the optical synchrotron continuum flux density, possibly providing a variable source of seed photons for inverse Compton scattering. In the radio bands, we find progressive delays of the most prominent light-curve maxima with decreasing frequency, as expected from the frequency dependence of the τ= 1 surface of synchrotron self-absorption. The global maximum in the 86 GHz light curve becomes less prominent at lower frequencies, while a local maximum, appearing in 2014, strengthens toward decreasing frequencies, becoming pronounced at ∼5 GHz. These tendencies suggest different Doppler boosting of stratified radio-emitting zones in the jet. © 2020 The Author(s). ; We thank the referee for attentive reading and comments that helped to improve presentation of the manuscript. The data collected by the WEBT collaboration are stored in the WEBT archive at the Osservatorio Astrofisico di Torino -INAF (ht tp://www.oato.inaf.it/blazars/webt/); for questions regarding their availability, please contact the WEBT President Massimo Villata(massimo.villata@inaf.it).TheSt.Petersburg University team acknowledges support from Russian Science Foundation grant 17-12-01029. The research at BU was supported in part by National Science Foundation grant AST-1615796 and NASA Fermi Guest Investigator grants 80NSSC17K0649, 80NSSC19K1504, and 80NSSC19K1505. The PRISM camera at Lowell Observatory was developed by K. Janes et al. at BU and Lowell Observatory, with funding from the NSF, BU, and Lowell Observatory. The emission-line observations made use of the DCT at Lowell Observatory, supported by Discovery Communications, Inc., BU, the University of Maryland, the University of Toledo, and Northern Arizona University. The VLBA is an instrument of the National Radio Astronomy Observatory. The National Radio Astronomy Observatory is a facility of the US NSF, operated under cooperative agreement by Associated Universities, Inc. This research has used data from the UMRAO which was supported by the University of Michigan; research at this facility was supported by NASA under awards NNX09AU16G, NNX10AP16G, NNX11AO13G, and NNX13AP18G, and by the NSF under award AST-0607523. The Steward Observatory spectropolarimetric monitoring project was supported by NASA Fermi Guest Investigator grants NNX08AW56G, NNX09AU10G, NNX12AO93G, and NNX15AU81G. The Torino group acknowledges financial contribution from agreement ASI-INAF n.2017-14-H.0 and from contract PRIN-SKA-CTA-INAF 2016. I.A. acknowledges support by a Ramon y Cajal grant (RYC-2013-14511) of the 'Ministerio de Ciencia, Innovacion, y Universidades (MICIU)' of Spain and from MCIU through the 'Center of Excellence Severo Ochoa' award for the Instituto de Astrofisica de Andalucia-CSIC (SEV-20170709). Acquisition and reduction of the POLAMI and MAPCAT data were supported by MICIU through grant AYA2016-80889-P. The POLAMI observations were carried out at the IRAM 30-m Telescope, supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). The MAPCAT observations were carried out at theGerman-Spanish Calar Alto Observatory, jointly operated by the Max-Plank-Institut fur Astronomie and the Instituto de Astrofisica de Andalucia-CSIC. The study is based partly on data obtained with the STELLA robotic telescopes in Tenerife, an AIP facility jointly operated by AIP and IAC. The OVRO 40-m monitoring program is supported in part by NASA grants NNX08AW31G, NNX11A043G, and NNX14AQ89G, and NSF grants AST-0808050 and AST-1109911. TH was supported by the Academy of Finland projects 317383 and 320085. AZT-24 observations were made within an agreement between Pulkovo, Rome and Teramo observatories. The Submillimeter Array is a joint project between the Smithsonian Astrophysical Observatory and the Academia Sinica Institute of Astronomy and Astrophysics and is funded by the Smithsonian Institution and the Academia Sinica. The Abastumani team acknowledges financial support by the Shota Rustaveli National Science Foundation under contract FR/217950/16. r This research was partially supported by the Bulgarian National Science Fund of the Ministry of Education and Science under grants DN 081/2016, DN 18-13/2017, KP-06-H28/3 (2018), and KP-06-PN38/1 (2019), Bulgarian National Science Programme 'Young Scientists and Postdoctoral Students 2019', Bulgarian National Science Fund under grant DN18-10/2017 and National RI Roadmap Projects DO1-157/28.08.2018 and DO1-153/28.08.2018 of the Ministry of Education and Science of the Republic of Bulgaria. GD and OV gratefully acknowledge observing grant support from the Institute of Astronomy and Rozhen National Astronomical Observatory via bilateral joint research project `Study of ICRF radio-sources and fast variable astronomical objects' (head -G. Damljanovic). This work was partly supported by the National Science Fund of the Ministry of Education and Science of Bulgaria under grant DN 08-20/2016, and by project RD-08-37/2019 of the University of Shumen. This work is a part of projects nos 176011, 176004, and 176021, supported by theMinistry of Education, Science and Technological Development of the Republic of Serbia. MGM acknowledges support through the Russian Government Program of Competitive Growth of Kazan Federal University. The Astronomical Observatory of the Autonomous Region of the Aosta Valley (OAVdA) is managed by the Fondazione Clement Fillietroz-ONLUS, which is supported by the Regional Government of the Aosta Valley, the Town Municipality of Nus and the 'Unite des Communes vald 'otainesMont-Emilius'. The research at the OAVdA was partially funded by several `Research and Education' annual grants from Fondazione CRT. This article is partly based on observations made with the IAC80 and TCS telescopes operated by the Instituto de Astrofisica de Canarias in the Spanish Observatorio del Teide on the island of Tenerife. A part of the observations were carried out using theRATAN-600 scientific equipment (SAO of the Russian Academy of Sciences).
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