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Research in Astronomy and Astrophysics 2016年第9期16卷 15-22页

作者： Diana Petrova Kiurkchieva Velimir Angelov Popov Doroteya Lyubenova Vasileva Nikola ivanov Petrov Department of Physics Shumen University115Universitetska Str.1712 ShumenBulgaria IRIDA Observatory 17A Prof.Asen Zlatarov Str.SofiaBulgaria Institute of Astronomy and National Astronomical Observatory Bulgarian Academy of Sciences72Tsarigradsko Shose Blvd.1784 SofiaBulgaria

Photometric observations in Sloan 9＇ and i＇ bands of four W UMa stars, NSVS 2244206, NSVS 908513, CSS J004004.7＋385531 and VSX J062624.4＋570907, are presented. The light curve solutions reveal that all targets have overcontact configurations with fillout factors within 0.15-0.26. Their components are G-K spectral types and are almost in thermal contact. They are also relatively close in size and luminosity： the radius ratios r2/r1 are within 0.75-0.90; the luminosity ratios 12/11 are within 0.53-0.63. The results of the light curve solution of CSS J004004.7＋385531 imply the weak limb-darkening effect of its primary component and possible presence of additional absorbing features in the system.

关键词： methods data analysis -- stars fundamental parameters -- stars binaries eclipsing individ-ual （NSVS 2244206, NSVS 908513, CSS J004004.7＋385531, VSX J062624.4＋570907）

Structure-activity relationship in water-gas shift reaction over gold catalysts supported on Y-doped ceria

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Journal of Rare Earths 2019年第4期37卷 383-392页

作者： Tatyana Tabakova Lyuba Ilieva Ivan ivanov Maela Manzoli Rodolfo Zanella Petya Petrova Zbigniew Kaszkur Institute of Catalysis Bulgarian Academy of Sciences Department of Drug Science and Technology & Centre for Nanostructured Interfaces and Surfaces University of Turin Centro de Ciencias Aplicadas y Desarrollo Tecnologico Universidad Nacional Autonoma de Mexico Institute of Physical Chemistry PAS

The utilization of pure hydrogen as an energy source in fuel cells gave rise to renewed interest in developing active and stable water-gas shift catalysts. Gold catalysts have proven to be very efficient for water-gas shift reaction at low temperature. The aim of the present study was to investigate the effect of:(i) different preparation methods(impregnation and coprecipitation) to obtain a modified ceria support,and(ii) the amount of Y_2 O_3(1.0 wt%, 2.5 wt%, 5.0 wt% and 7.5 wt%) as dopant on the water-gas shift activity of Au/CeO_2 catalysts. An extended characterization by means of S_(BET), XRD, HRTEM/HAADF, FTIR,H_2-TPR and CO-TPR measurements in combination with careful evaluation of the catalyst behavior allowed to shed light on the parameters governing the water-gas shift activity. The catalysts show very high activity(>90% CO conversion) in the temperature range 180-220 ℃,with a slightly better performance of the gold catalysts on supports prepared by impregnation. The decreased activity with increasing Y_2 O_3 concentration is related to the hindering of oxygen mobility due to ordering of surface oxygen vacancies in vicinity of segregated Y^(3+). The effect of catalyst pre-treatments and the stability of the best performing samples were examined as well.

关键词： Gold catalyst Water gas shift reaction Doped ceria Yttrium Hydrogen production Rare earths

Results of the Main Phase of Ion Separation in the Process of Plasma-Optical Mass Separation

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Plasma Science and Technology 2015年第10期17卷 862-868页

作者： V.M.BARDAKOV S.D.ivanov A.V.KAZANTSEV N.A.STROKIN Institute for Physics and Technology Irkutsk State Technical University

This paper presents separation results of a mixture of nitrogen, argon and krypton ions in the process of plasma-optical mass separation on the POMS-E-3 separator model. We determined the behavior of the separation with a change in the value of magnetic field induction in the azimuthator and in the degree of compensation of the spatial charge in ion flows. An analysis is performed for experimental data by correlation with the results of a theoretical study and numerical experiments. The objectives of future experiments are outlined.

关键词： plasma-optical mass separation plasma accelerator trajectories spatial charge

Geological Structure and Historical Development of Pre-Jurrasic Basement of West Siberia Oil- and Gas-Bearing Megabasin Karabash Zone

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Open Journal of Geology 2022年第10期12卷 717-738页

作者： Kirill Svjatoslavich ivanov Nikolay Pavlovich Kostrov Yuriy Viktorovich Erokhin Vladimir Sergeevich Ponomarev Institute of Geology and Geochemistry Urals Branch of Russian Academy of Sciences Yekaterinburg Russia

An additional comprehensive study of the west Siberia Karabash zone basement has been conducted. Core samples from more than 300 wells that opened the rocks of the basement were analyzed by different methods. A new map of the pre-Jurassic basement of Karabash zone of the west part of the Khanty-Mansi Autonomous Okrug (KhMAO) has been made. For the first time for the West Siberia megabasin U-Pb dating was made for samples from Shaim-Kuznetsovsk meganticlinorium and late to middle Devonian ages were obtained. The Devonian ages was obtained for metamorphic complexes of the region and, in general, for the basement of West Siberia. The complexes considered as Precambrian before that. The obtained results enable significantly to clarify more exact history of pre-Jurassic rock forming for the basement of the west part of West Siberia craton and its structure in the limits of Karabash zone. Thus, obtained data testify that in pre-Jurassic basement of the west part of the West Siberia (Karabash zone), filling grabens basalt effusion began during Permian time (probably at the end of early Permian) at sublatitudinal compression, that is, at collision, possibly immediately after or subsynchronously with the origin of the granite. On the edge of Permian and Triassic (or in early Triassic), sublatitudinal compression changed into stretching, and submeridional grabens came to existence and basalt effusion came up to the maximum.

关键词： Zircon Age Definition West Siberia Pre-Jurassic Basement Triassic Graben-Rifts

Effect of the addition of rare earths on the activity of alumina supported copper cobaltite in CO oxidation, CH_4 oxidationand NO decomposition

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Journal of Rare Earths 2015年第4期33卷 382-390页

作者： B.ivanov I.Spassova M.Milanova G.Tyuliev M.Khristova Institute of General and Inorganic Chemistry Bulgarian Academy of Sciences Faculty of Chemistry and Pharmacy Sofia University Institute of Catalysis Bulgarian Academy of Sciences

The effect of the addition of small amounts of rare earths （Ln=La, Ce, Nd and Gd） to alumina supported copper-cobalt spinel oxide on the catalysts efficiency in CO and CH4 oxidation and in NO decomposition was investigated. Samples of Ln/CuCo/AI catalyst were prepared and characterized by X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, atomic absorption spectroscopy （AAS）, scanning electron mieroscopy-energy dispersive spectroscopy （SEM-EDS）, H2-temperature-programmed reduc- tion （H2-TPR）, electron paramagnetic resonanee （EPR） spectroscopy and low temperature nitrogen adsorption, The results showed that the addition of rare earths changed the surface state of the alumina supported copper-cobalt spinel catalyst. As a result, partial re- duction of copper species was observed as well as migration of these species between the surface and the bulk. The Ln/CuCo/A1 catalysts behaved differently in oxidation and reduction processes. In oxidation processes where oxide structure was important, Ce/CuCo/A1 and Nd/CuCo/A1 were the most active catalysts. The catalyst Ce/CuCo/AI was the most active in the oxidation reactions because of the availability and favorable surface distribution of the redox couples Cu＋/Cu2＋ and Ce3＋/Ce4＋. In NO decompostion, Ln-modified catalysts significantly improved the selectivity of the process to N2.

关键词： copper cobaltite NO decomposition CO oxidation CH4 oxidation rare earths

Comparative analysis of thinning techniques in pine forests

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Journal of Forestry Research 2022年第4期33卷 1145-1156页

作者： Maame Esi Hammond Radek Pokorný Simon Abugre Augustine Gyedu Department of Silviculture Faculty of Forestry and Wood TechnologyMendel University in BrnoZemědělská361300 BrnoCzech Republic Department of Forest Science School of Natural ResourcesUniversity of Energy and Natural ResourcesP.O.Box 214SunyaniGhana Forest Services Division(FSD) P.M.BKumasiGhana

Thinning is a necessary and complex forestry activity.The complexity increases due to theoretical disagreements,contradictory recommendations,and errors of modern practice,which require confirmation through longtime experiments.This article presents a summary of experimental results from plantations established 20–30 years ago and explains concepts of the theory,methods,and regime of thinning in permanent sample plots of pine stands in Gatchinsky forest of the Leningrad region.The research results allow for the clarification of growth patterns and age dynamics of pine stands subject to heavy,low thinning,as well as the results of applying the crown(high)thinning technique and a mixed treatment.A combined thinning and fertilization could improve wood quality and yield compared to conventional methods.Of particular scientific importance is the analysis of change in tree diameter classes during growth and after thinning.The research results allow for optimizing the treatment regime in pine plantations and reducing labor intensity by increasing the intensity of thinning and reducing the number of techniques.

关键词： Forest management practices Forest stand Selective thinning Silviculture

Ethical and Moral Competences of Upper Secondary Students:A Comparative Study

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ECNU Review of Education 2021年第4期4卷 686-706页

作者：彭正梅 Dietrich Benner Roumiana Nikolova Stanislav ivanov 彭韬 East China Normal University Humboldt University of Berlin Institute of Education Monitoring and Quality Development Institute of Moral Education Nanjing Normal UniversityNanjingJiangsuChina

Purpose:This article presents the theoretical framework,research design,methodology,and main findings of the comparative measurement of ethical-moral competences of 15-year-old upper secondary students in Shanghai,under the ETiK-International-Shanghai project.Design/Approach/Methods:By dividing the ethical-moral competences into the categories of basic ethical-moral knowledge,ethical-moral judgment competence,and competence in developing ethical-moral action plans,a survey of 2,036 students was conducted,using a reliable and valid testing instrument.Findings:In general,15-year-olds from homes with more educational resources perform higher in all three scales across all countries taken under consideration in our study.Furthermore,school practices,teaching,as well as quantity and quality of instruction play a very important role in the moral education process and especially in developing students’proficiency levels of ethical-moral knowledge,reasoning competence,as well as students’high abilities in developing moral action plans.When relevant educational background factors are held constant,Chinese students show lower average scores on basic ethical-moral knowledge and moral judgment competence.With exception of the tested Vienna students,all other European samples scored better than the Chinese students—also on the test for developing ethical-moral action plans.However,Chinese students are especially able to display outstanding empathy when dealing with suffering,misfortune,and sorrow,as well as in their willingness to help others.Originality/Value:The findings of this article can foster thinking about which topics should be further discussed to improve the ethical-moral knowledge and competences of Chinese students and highlight requirements for the further development of moral education in China at the levels of teaching,curriculum,teacher education,and research.

关键词： Basic ethical-moral knowledge competence in developing ethical-moral action plans ethical-moral judgment competence ETiK moral education

Vania Nikolaeva Anastasova,Elean ivanov Zanzov and Elena Sergeeva Krasteva

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Journal of Pharmacy and Pharmacology 2021年第11期9卷 369-377页

作者： Vania Nikolaeva Anastasova Elean ivanov Zanzov Elena Sergeeva Krasteva Department of Burns PlasticReconstructive and Aesthetic SurgeryMedical University“Plovdiv”“St.George”University HospitalNo.66 Str.“Peshtersko shose”PlovdivBulgaria

Background:Worldwide,annually,11 million people seek medical assistance due to burn traumatic injuries.Most of the mare attributable to natural disasters,work accidents and domestic burns,in some cases,they may indicate the presence of child abuse.Management of facial burns presents a challenge to surgeons as burn traumas involving the face result in both physical and psychological injury.Objective:The aim of the present study is to investigate the effect of Theresienöl®in cases of facial burns.Method:Over a period of two years,the study contingent was 53 patients.Patients were selected from those attending the Department of Burns,Plastic,Reconstructive and Aesthetic Surgery at―St.George‖University Hospital,Medical University―Plovdiv‖.They were subdivided into groups according to age,gender,etiology and degree of burns as well as duration of treatment.Once per day our patients received treatment with Theresienöl®based on an open approach,with rubbing of the substance with massage movements,thus securing impregnation of the oil in the damages areas.Results:We monitored a very good penetration of the oil in the eschars and consequently-their more rapid separation and better esthetic results.Patients reported complete recovery with very good esthetic result to day 14.Based on our study protocol,it was used in the management of superficial facial wounds with a very good outcome.Conclusions:Theresienöl®is a patent product that is used in the treatment of difficult to heal wounds,burns,edemas and after surgery.

关键词： Face burn Theresienöl® natural product conservative treatment face scars

Influence of Features of Interphase Boundaries on Mechanical Properties and Fracture Pattern in Metal-Ceramic Composites

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Journal of Materials Science & Technology 2013年第11期29卷 1025-1034页

作者： Sergey Psakhie Vladimir Ovcharenko Baohai Yu Evgeny Shilko Sergey Astafurov Yury ivanov Alexey Byeli Alexey Mokhovikov Institute of Strength Physics and Materials Science Siberian Branch of the Russian Academy of Sciences Institute of High Technology Physics Tomsk Polytechnic University Shenyang National Laboratory for Materials Science Institute of High Current Electronics Siberian Branch of the Russian Academy of Sciences Physical-Technical Institute Yurga Technological Institute Tomsk Polytechnic University

The results of a theoretical study on the influence of strength of interphase boundaries in metal-ceramic composite on macroscopical characteristics of composite response such as strength, deformation capacity, fracture energy and fracture pattern are presented. The study was conducted by means of computer-aided simulation by means of movable cellular automaton method taking account of a developed ＂mesoscopical＂ structural model of particle-reinforced composite. The strength of interphase boundaries is found to be a key structural factor determining not only the strength properties of metal-ceramic composite, but also the pattern and rate of fracture. The principles for achievement of the high-strength values of particle/binder interfaces in the metal-ceramic composition due to the formation of the wide transition zones （areas of variable chemical composition） at the interphase boundaries are discussed. Simulation results confirm that such transition zones provide a change in fracture mechanism and make the achievement of a high-strength and a high deformation capacity of metal-ceramic composite possible.

关键词： Metal--ceramic composites Particle-reinforced composite Interphase boundaries Discrete element based analysis Strength and fracture energy Fracture pattern

Polymeric Structure and Solid ^(31)P, ^(113)Cd NMR Spectra of Cadmium(II) Dialkyldithiophosphate (Alkyl = n-butyl and i-butyl)

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Chinese Chemical Letters 2003年第2期14卷 188-190页

作者： Ye Gao YIN Willis FORSLING Dan BOSTROM Oleg ANTZUTKIN Mats LINDBERG Alexander ivanov Department of Chemistry Faculty of ScienceThe University of ShantouShantou 515063 Division of Inorganic Chemistry Department of Chemical and Metallurgical Engineering Lule?University of Technology.Lule?se-97187Sweden Department of Chemistry Ume UniversityUme se-90187-Sweden

Two polymeric complexes, [Cd(BTP)2]n 1 and [Cd(i-BTP)2]n 2, were prepared and investigated by solid 31P and 113Cd NMR spectroscopies. The crystal structure of 2 was determined by X-ray diffraction.

关键词： Cadmium(II) complex dialkyldithiophosphate crystal structure solid NMR.