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Newly identified Au-Ag-Bi-Te mineralization in the Aydindere skarn Fe and Cu deposit， Giresun， NE Turkey: implications of gold mineralization during retrograde skarn evolution

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Journal of Earth Science 2024年

作者： Ahmet Sasmaz Vitaliy Sukach serhiy Bondarenko Hryhorii Aleksiienko Hengameh Erfanian Kaseb Bilge Sasmaz Sergiy Kurylo Oleksandr Hrinchenko Volodymyr Somka Panagiotis Voudouris Department of Geology Firat University Faculty of Geology and Geoenvironment National and Kapodistrian University of Athens Mineralogy and Ore Formation of National Academy of Science M.P.Semenenko Institute of Geochemistry 3. Department of Petroleum Engineering Eqbal Lahoori Institute of Higher Education

This study investigates the mineralogy and mineral-chemistry of a newly discovered Au-Ag-Bi-Te mineralization at the Aydindere Fe-Cu skarn deposit， within the Pontides Tectonic Unit， northeastern Turkey. The mineralization is developed in the skarn zone at the contact between Upper Cretaceous andesite-pyroclastic rocks and a Paleocene-Eocene I-type granitoid. The principal ore minerals of the Aydindere Fe-Cu deposit are oxides (magnetite)， sulfides (pyrite-chalcopyrite-galena-sphalerite)， tellurides/sulfotellurides (tetradymite， hessite)， sulfosalts (wittichenite， emplectite， aikinite) and native gold-electrum. Skarn minerals include anhydrous phases (garnet) formed in a prograde stage and hydrous phases (amphibole， epidote， chlorite)， which were formed in a retrograde stage in association with quartz， adularia， apatite and late calcite. Sulfides， tellurides and sulfosalts are introduced during the retrograde stage. The Au-Ag-Bi-Te mineralization was detected for the first time within the western ore body of the Aydindere deposit， and occurs in calcite-bearing sulfide bodies that cut magnetite-garnet-amphibole-epidote skarns with magnetite ores of different grade， including massive magnetite. Chlorite geothermometry indicates formation of the Au-Ag-Bi-Te mineralization at temperatures between 300 and 250 °C， during the retrograde skarn evolution. Assuming the temperature is ～275°C， logfS2= -10.5 to -13， logfO2= -37 to -33， and logfTe2values range from approximately -12 to -8.5 were estimated. The available mineralogical and geological data (presences of magnetite， oxidized-type tellurides/sulfotellurides， and andraditic garnets， and absence of pyrrhotite and arsenopyrite) suggest that Aydindere is an oxidized Au-bearing skarn deposit. The discovery of Au-Ag-Bi-Te mineralization at Aydindere increases its productivity and requires more detailed exploration in the deposit for precious (Au， Ag) and critical (Bi， Te) metals.

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Peculiarities of gender disambiguation and ordering of non-English authors’names for Economic papers beyond core databases

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Journal of Data and Information Science 2023年第1期8卷 72-89页

作者： Olesya Mryglod Serhii Nazarovets serhiy Kozmenko Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine 1 Svientsitskii St.79011 LvivUkraine Borys Grinchenko Kyiv University 18/2 Bulvarno-Kudriavska Str.04053 KyivUkraine University of Social Sciences Spoleczna Akademia Nauk 9 Sienkiewicza St.90-113 LodzPoland

Purpose:To supplement the quantitative portrait of Ukrainian Economics discipline with the results of gender and author ordering analysis at the level of individual authors,special methods of working with bibliographic data with a predominant share of non-English authors are used.The properties of gender mixing,the likelihood of male and female authors occupying the first position in the authorship list,as well as the arrangements of names are studied.Design/methodology/approach:A data set containing bibliographic records related to Ukrainian journal publications in the field of Economics is constructed using Crossref metadata.Partial semi-automatic disambiguation of authors’names is performed.First names,along with gender-specific ethnic surnames,are used for gender disambiguation required for further comparative gender analysis.Random reshuffling of data is used to determine the impact of gender correlations.To assess the level of alphabetization for our data set,both Latin and Cyrillic versions of names are taken into account.Findings:The lack of well-structured metadata and the poor use of digital identifiers lead to numerous problems with automatization of bibliographic data pre-processing,especially in the case of publications by non-Western authors.The described stages for working with such specific data help to work at the level of authors and analyse,in particular,gender issues.Despite the larger number of female authors,gender equality is more likely to be reported at the individual level for the discipline of Ukrainian Economics.The tendencies towards collaborative or solo-publications and gender mixing patterns are found to be dependent on the journal:the differences for publications indexed in Scopus and/or Web of Science databases are found.It has also been found that Ukrainian Economics research is characterized by rather a non-alphabetical order of authors.Research limitations:Only partial authors’name disambiguation is performed in a semi-automatic way.Gender labels can be derived only for author

关键词： Scholarly metadata Economics Crossref Open Ukrainian Citation Index Ukraine,Gender non-Western authors

Surrogate role of machine learning in motor-drive optimization for more-electric aircraft applications

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Chinese Journal of Aeronautics 2023年第2期36卷 213-228页

作者： Yuan GAO Benjamin CHEONG serhiy BOZHKO Pat WHEELER Chris GERADA Tao YANG Power Electronics Machines and Control GroupUniversity of NottinghamNottingham NG 72RDUK School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore

Motor drives form an essential part of the electric compressors,pumps,braking and actuation systems in the More-Electric Aircraft(MEA).In this paper,the application of Machine Learning(ML)in motor-drive design and optimization process is investigated.The general idea of using ML is to train surrogate models for the optimization.This training process is based on sample data collected from detailed simulation or experiment of motor drives.However,the Surrogate Role(SR)of ML may vary for different applications.This paper first introduces the principles of ML and then proposes two SRs(direct mapping approach and correction approach)of the ML in a motor-drive optimization process.Two different cases are given for the method comparison and validation of ML SRs.The first case is using the sample data from experiments to train the ML surrogate models.For the second case,the joint-simulation data is utilized for a multi-objective motor-drive optimization problem.It is found that both surrogate roles of ML can provide a good mapping model for the cases and in the second case,three feasible design schemes of ML are proposed and validated for the two SRs.Regarding the time consumption in optimizaiton,the proposed ML models can give one motor-drive design point up to 0.044 s while it takes more than 1.5 mins for the used simulation-based models.

关键词： Artificial Neural Network(ANN) Design and Optimization Machine Learning(ML) More-Electric Aircraft(MEA) Motor drive Permanent Magnet Synchronous Motor(PMSM) Search Algorithm Surrogate Algorithm

Neural Network aided PMSM multi-objective design and optimization for more-electric aircraft applications

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Chinese Journal of Aeronautics 2022年第10期35卷 233-246页

作者： Yuan GAO Tao YANG serhiy BOZHKO Pat WHEELER Tomislav DRAGICEVIC Chris GERADA Power Electronics Machines and Control GroupUniversity of NottinghamNottingham NG72RDUK Department of Electrical Engineering Technical University of DenmarkKgs.Lyngby 2800Denmark

This study uses the Neural Network(NN)technique to optimize design of surfacemounted Permanent Magnet Synchronous Motors(PMSMs)for More-Electric Aircraft(MEA)applications.The key role of NN is to provide dedicated correction factors for the analytical PMSM mass and loss estimation within the entire design space.Based on that,a globally optimal design can be quickly obtained.Matching the analytical estimation with Finite-Element Analysis(FEA)is the main research target of training the NN.Conventional analytical formulae serve as the basis of this study,but they are prone to loss accuracy(especially for a large design space)due to their assumptions and simplifications.With the help of the trained NNs,the analytical motor model can give an estimation as accurate as the FEA but with super less time during the optimization process.The Average Correction Factor(ACF)approach is regarded as the comparison method to demonstrate the excellent performance of the proposed NN model.Furthermore,a NN aided three-stage-sevenstep optimization methodology is proposed.Finally,a Pole-10-Slot-12 PMSM case study is given to demonstrate the feasibility and gain of the NN aided multi-objective optimization approach.In this case,the NN aided analytical model can generate one motor design in 0.04 s while it takes more than 1 min for the used FEA model.

关键词： Design and optimization Loss estimation Mean Length per Turn(MLT) More-Electric Aircraft(MEA) Neural Network(NN) Permanent Magnet Synchronous Motor(PMSM)

Dissolution of WO_(3) modified with IrO_(x) overlayers during photoelectrochemical water splitting

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SusMat 2023年第1期3卷 128-136页

作者： Ken J.Jenewein Julius Knopel AndréHofer Attila Kormányos Britta Mayerhofer Florian D.Speck Markus Bierling Simon Thiele Julien Bachmann serhiy Cherevko Helmholtz Institute Erlangen-Nürnberg for Renewable Energy(IEK-11) Forschungszentrum Jülich GmbHErlangenGermany Department of Chemical and Biological Engineering Friedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany Chemistry of Thin Film Materials Department of Chemistry and PharmacyFriedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany Department of Physical Chemistry and Materials Science Interdisciplinary Excellence CentreUniversity of SzegedSzegedHungary

WO_(3),an abundant transition metal semiconductor,is one of the most discussed materials to be used as a photoanode in photoelectrochemical water-splitting devices.The photoelectrochemical properties,such as photoactivity and selectivity of WO_(3) in different electrolytes,are already well understood.However,the understanding of stability,one of the most important properties for utilization in a commercial device,is still in the early stages.In this work,a photoelectrochemical scanning flow cell coupled to an inductively coupled plasma mass spectrometer is applied to determine the influence of co-catalyst overlayers on photoanode stability.Spray-coatedWO_(3) photoanodes are used as a model system.Iridium is applied to the electrodes by atomic layer deposition in controlled layer thickness,as determined by ellipsometry and x-ray photoelectron spectroscopy.Photoactivity of the iridium-modified WO_(3) photoanodes decreases with increasing iridium layer thickness.Partial blocking of the WO_(3) surface by iridium is proposed as the main cause of the decreased photoelectrochemical performance.On the other hand,the stability of WO_(3) is notably increased even in the presence of the thinnest investigated iridium overlayer.Based on our findings,we provide a set of strategies to synthesize nanocomposite photoelectrodes simultaneously possessing high photoelectrochemical activity and photostability.

关键词： dissolution in situ ICP-MS overlayers PEC-SFC photoelectrochemistry

Simulation of the Traweling Wave Burning Regime on Epithermal Neutrons

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World Journal of Nuclear Science and Technology 2023年第4期13卷 73-90页

作者： Viktor Tarasov serhiy Chernezhenko Iryna Korduba Volodymyr Vashchenko Department of Theoretical and Experimental Nuclear Physics Odessa National Polytechnic University Odesa Ukraine Department of Environmental Protection Technologies and Labor Protection National University of Construction and Architecture Odesa Ukraine Interdepartmental Scientific Center for Fundamental Research on Energy and Ecology of the National Academy of Sciences of Ukraine “Odesa Polytechnic” and Ministry of Ecology Odessa Ukraine

New results of two computer experiments on modeling of superthermal neutron-nuclear combustion of natural uranium for two different flux densities of external neutron source and duration of half a year each are presented. The simulation results demonstrate the dependence of the autowave combustion modes on the parameters of the external source.

关键词： Wave Reactor Computer Modeling Neutron Nuclear Combustion Neutron Thermal Spectrum Natural Uranium Combustion

Generic functional modelling of multi-pulse auto-transformer rectifier units for more-electric aircraft applications

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Chinese Journal of Aeronautics 2018年第5期31卷 883-891页

作者： Tao YANG serhiy BOZHKO Patrick WHEELER Shaoping WANG Shuai WU Department of Electrical and Electronic Engineering University of Nottingham School of Automation Science and Electrical Engineering Beihang University

The Auto-Transformer Rectifier Unit（ATRU） is one preferred solution for high-power AC/DC power conversion in aircraft. This is mainly due to its simple structure, high reliability and reduced k VA ratings. Indeed, the ATRU has become a preferred AC/DC solution to supply power to the electric environment control system on-board future aircraft. In this paper, a general modelling method for ATRUs is introduced. The developed model is based on the fact that the DC voltage and current are strongly related to the voltage and current vectors at the AC terminals of ATRUs. In this paper, we carry on our research in modelling symmetric 18-pulse ATRUs and develop a generic modelling technique. The developed generic model can study not only symmetric but also asymmetric ATRUs. An 18-pulse asymmetric ATRU is used to demonstrate the accuracy and efficiency of the developed model by comparing with corresponding detailed switching SABER models provided by our industrial partner. The functional models also allow accelerated and accurate simulations and thus enable whole-scale more-electric aircraft electrical power system studies in the future.

关键词： Asymmetric transformer Functional modelling More-Electric Aircraft Multi-pulse rectifier Transformer rectifier unit

Lignite oxidative desulphurization Notice 1.Process condition selection

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International Journal of Coal Science & Technology 2014年第1期1卷 62-69页

作者： Volodymyr Gunka serhiy Pyshyev Institute of Chemistry and Chemical Technologies Lviv Polytecnic National University12 Bandery Str.Lviv 79013Ukraine

The process of lignite desulphurization via its treatment by an oxidant(air or air–steam mixture)has been studied.The research objective was useful determination of steam application in oxidative lignite desulphurization.It has been proved that the water steam should be included in the oxidant composition to increase the hydrogen sulphide and combustible constituent content in the gases obtained during the processes under research.The impact of factors which affect the reactions between solid(in our case–lignite)and gaseous reagent(oxidant,i.***.air and or air–steam mixture)upon the research process has been investigated,if these reactions occur in the kinetic area.Such factors are linear rate of oxidant movement and coal grain size.The values of oxidant movement linear rate and coal grain size,which the reaction transfer from pyrite sulphur and organic content of lignite from diffusion into kinetic area occurs by,have been determined.Under these‘‘transfer’’conditions,the values of coefficients of oxidant mass transfer(β,m/s)as well as Sherwood criteria and boiling layer differences have been calculated.

关键词： Lignite Oxidative desulphurization Pyrite Sulphur Hydrogen sulphide

Lignite oxidative desulphurization. Notice 2： effects of process parameters

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International Journal of Coal Science & Technology 2015年第3期2卷 196-201页

作者： Volodymyr Gunka serhiy Pyshyevt Institute of Chemistry and Chemical Technologies LvivPolytecnic National University 12 Bandery Str. Lviv 79013Ukraine

The influence of main characteristics upon conversion directions of the lignite organic part during its oxidation desulphurization was studied. The optimum temperature values, the ratio oxidant : raw material, and time of coal stay in the reaction zone, which provide the maximum degree of sulphur conversion and hydrogen sulphide content in desulphurization gases, were calculated. The process implemented under these conditions will decrease environment pollution by sulphur dioxide during further lignite burning at least to 55 %–60 % and utilize sulphur in coal in the form of desulphurization gases with hydrogen sulphide content of 7 %. Such gases can be reprocessed by the known methods of obtaining sulphur. The effect of the above three factors on the depth and character of the coal organic matter transformation was studied.

关键词：氧化脱硫工艺参数褐煤脱硫过程硫转化率环境污染二氧化硫煤炭脱硫