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Acta Geochimica 2019年第2期38卷 262-276页

作者： p.v.smirnov A.O.Konstantinov G.A.Batalin B.I.Gareev Tyumen Industrial University Technische Universit?t Clausthal Kazan Federal University

This paper presents lithologic and geochemical data from the sequence of the Eocene Irbit formation siliceous rocks(Transuralian Region) outcropping in a quarry in the Irbit deposit(thickness of 15 m) and in a large natural outcrop, Belaya Gorka(thickness of 13 m). The data show that both outcrops are composed of diatomites and clayey diatomites, both characterized by a certain degree of lithologic heterogeneity around their chemical,granulometric, and mineralogical compositions;microstructural features; and degree of diatom preservation. The values of indices important for the classification of siliceous rocks and determination of prospects for their industrial application—SiO_2, Al_2O_3, Fe_2O_3, and clay fraction content—ranged from 66% to 77%, 7% to 14%,3.00% to 5.60%, and 23% to 50%, respectively. In all studied lithologic varieties, element abundances of v, Cr,Mn, Co, Ni, Cu, Zn, Ga, Ge, and Sb were two to three times higher than their respective abundances in the Earth's crust. This is probably related to these elements' involvement in the biological cycle and favorable conditions for transport. Rb, Cs, Ba, and Sr, as well as rare earth elements,are considered the most reliable indicators of lithologic and geochemical subdivision of a sequence of siliceous rocks,as they are associated mainly with clayey minerals. variations in these indicators have recorded, with great probability, even short-term cycles and semi-cycles of silicasedimentation in the Transuralian Region, as well as tectonic regime and involvement of terrigenous influx.

关键词： Diatomite Clayey diatomite Irbit formation Eocene Geochemical variability

Ion-conducting Membranes Based on Bacterial Cellulose Nanofibers Modified by poly(sodium acrylate-co-2-acrylamido-2-methylpropanesulfonic acid)

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Chinese Journal of polymer Science 2024年第3期42卷 333-343,I0007页

作者： Elizaveta v.Batishcheva Nikolay N.smirnov Natalya v.Bobrova Maria p.Sokolova Michael A.smirnov Institute of Macromolecular Compounds Russian Academy of SciencesBolshoy pr.31Saint Petersburg 199004Russia

Green method for preparation of ion-conducting membranes(ICM) based on bacterial cellulose nanofibers(CNF) modified by a copolymer of sodium acrylate and 2-acrylamido-2-methylpropanesulfonic acid was elaborated. FTIR and NMR data confirmed grafting of polyacrylate onto cellulose surface. Formation of porous structure of the ICM was controlled by SEM and AFM. The maximal ionic conductivity of the membranes reaches 1.5 and 3.1 mS·cm^(-1)(60 ℃ and 98% relative humidity) when they are saturated with water or H_2SO_4(1 mol·L^(-1)) electrolyte,respectively. prepared ICM was tested as a separator in a symmetrical supercapacitor with electrodes based on polyaniline hydrogel. The assembled cell demonstrate ability to operate at high current density up to 100 A·g^(-1) maintaining specific capacitance 165 F·g^(-1). Maximal specific capacitance of 289 F·g^(-1) was achieved at current density 1 A·g^(-1). Retaining of 90% of initial capacitance after 10000 of charge-discharge cycles proves high electrochemical stability of prepared ICM.

关键词： Bacterial cellulose Ion conductivity porous membrane Supercapacitor

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对苯二甲酸二甲酯与乙二醇的酯交换反应

国外纺织技术 1985年第4期 14-16页

作者： p.v.smirnov 张文光

在聚对苯二甲酸乙二酯(pET)的合成中,对苯二甲酸二甲酯(DWT)和乙二醇(EG)酯交换产物的组成能显著影响预缩聚和后缩聚反应的速率。甲醋基的醋交换反应和经基乙氧基的缩合结果可得到各种组成的复杂棍合物

关键词：低聚物克分子比端基聚合度乙氧基烷氧基 DMT 交换反应 EG 乙二醇二元醇

Self-healable and Robust Film Based on Electroactive polymer Brush as Electrode for Flexible Supercapacitor

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Chinese Journal of polymer Science 2024年第8期42卷 1049-1059页

作者： Maria p.Sokolova vitaly K.vorobiov Nikolay N.smirnov Ivan S.Kuryndin Natalya v.Bobrova Michael A.smirnov Institute of Macromolecular Compounds Russian Academy of SciencesBolshoy pr.31Saint Petersburg 199004Russia

The aim of this study was to develop self-healable and robust elect roconductive film based on polyaniline copolymer for application as electrode in flexible *** this purpose,the electroconductive polymer brushes(EpB)was *** synthesis of EpB is based on graft polymerizations of acrylamide(AAm)on poly(vinyl alcohol)(pvA)with formation of pvA-pAAm polymer brush and subsequent graft copolymerization of aniline and p-phenylenediamine on pvA-pAAm resulting in formation of EpB with electroconducting copoly(aniline-co-pphenylenediamine)(pAph DA).It was found that the ratio between pvA and pAAm at the first stage greatly influence the electrochemical performance of the *** films were prepared by casting of EpB solution with subsequent *** of electrical current distribution through the film with AFM reveal more uniform distribution of pAphDA in EpB in comparison with reference pvA-pAphDA and pAAm-pAphDA *** was demonstrated that mechanical cha racteristics and electrical conductivity values of films restore at large extent after curring and self-healing under optimal relative humidity level(58%).The flexile supercapacitor cell with EpB film electrodes demon strate specific capacitance 602 mF·cm^(-2)at the current density of 1 mA·cm^(-2)and retention 94%of initial capacitance after 5000 charge/discharge cycles.

关键词： polymer brush polyaniline Flexible supercapacitor Self-healing Electroconducting film

Exploring the potential of drill cuttings for reservoir characterization:A case study from the volga-Ural basin,Russia

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petroleum Research 2024年第2期9卷 193-205页

作者： Ibrahem Yousef v.p.Morozov Kazan Federal University Institute of Geology and Petroleum Technologies420008Russian Federation

The research objectives are to assess the possibility of using drill cutting analysis to obtain information about the mineralogical and geochemical properties of the reservoir *** cutting samples were collected from a vertical well that penetrated the Domanik sediments(Semiluksk Formation)in one of the oil fields in the volga-Ural petroleum *** sections from drill cuttings were examined using an optical polarizing microscope(Axio Imager A2).X-ray diffraction(XRD)analyses were performed using a Brucker D2 phaser X-ray powder *** properties were studied using an STA 449 F3 Jupiter *** pyrolytic studies were performed using the Rock-Eval *** inspection showed that the studied sediments are alternations of carbonates and siliceous-carbonate *** section examinations revealed that the carbonates are mainly limestone(mudstone and wackestone)and are characterized by a dense texture and up to 30%organic *** siliceous-carbonate rocks are dominated by siliceous mudstones and are characterized by dark colours,layered structure,and an enrichment in organic *** analyses showed that the carbonate rocks are mainly composed of calcite,dolomite,quartz,feldspar,and mica,which are minor *** siliceous-carbonate rocks are dominated by quartz,followed by calcite,although they also contain feldspars,mica,dolomite,and pyrite as *** to the simultaneous thermal analysis,the average total hydrocarbon in the carbonate and siliceous-carbonate rocks is 13.6%(for the core samples)and 11.5%(for the drill cutting samples).The content of heavy hydrocarbons in the rocks is higher than the content of light hydrocarbons,indicating the immature nature of organic *** is found sporadically in siliceous-carbonate *** to the pyrolytic studies,average S1 is 4.4 mg/g and average S2 is 19.8 mg/g(for the core samples);average S1 is 2.1 mg/g and average S2 is 17.8 mg/g(for the

关键词： Drill cuttings Reservoir characterization Domanik Semiluksk volga-Ural Russia

Emission colour tuning in KLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)phosphor

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Journal of Rare Earths 2024年第1期42卷 57-65,I0002页

作者： Janani K Gayathri E vijayatha v Ramasubramanian S Thiyagarajan p Department of Science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of Sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction *** each of the Yb^(3+)/Er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth Er/Ho doped KYbF4shows strong red emission compared to other ***_(4):Yb,Er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,Er-doped KGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using Uv light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths Energy transfer upconversion Downshifting Colour coordinates

Mesenchymal stem cells in wound healing:A bibliometric analysis as a powerful research tool

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World Journal of Stem Cells 2024年第9期16卷 827-831页

作者： vera v voinova Daria v vasina Anton p Bonartsev Faculty of Biology MV Lomonosov Moscow State UniversityMoscow 119234Russia NF Gamaleya National Research Centre for Epidemiology and Microbiology Ministry of Health of the Russian FederationMoscow 123098Russia

Bibliographic analysis is still very rarely used in experimental basic study *** comprehensive bibliometric analysis of scientific literature on research progress and challenges in stem cell therapy for diabetic chronic wounds,which was conducted in the work of Shi et al can be a case study and a source of valuable information for writing reviews and experimental papers in this *** experimental studies on a role of mesenchymal stem cells(MSCs)in wound healing that are published in 2023-2024,such as Zhang et al in 2023,Hu et al in 2023,Wang et al in 2023 are certainly also subjects for applying this powerful tool to analyze current research,challenges and perspectives in this *** is due to the fact that these studies have addressed a great variety of aspects of the application of MSCs for the treatment of chronic wounds,such as using both the cells themselves and their various products:Sponges,hydrogels,exosomes,and genetic *** a wide variety of directions in the field of study and biomedical application of MSCs requires a deep understanding of the current state of research in this area,which can be provided by bibliometric ***,the use of such elements of bibliographic analysis as publication count by year and analysis of top-10 keywords calculated independently or cited from bibliometric analysis studies can be safely recommended for every basic study manuscripts,primarily for the“Introduction”section,and review.

关键词： Bibliometric analysis Mesenchymal stem cells Wound healing Tissue engineering Dressing Hydrogels Matrix Exosomes

Intertype superconductivity evoked by the interplay of disorder and multiple bands

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Frontiers of physics 2024年第4期19卷 81-89页

作者： p.M.Marychev A.A.Shanenko A.v.vagov HSE University 101000 MoscowRussia Center for Advanced Mesoscience and Nanotechnology MIPTDolgoprudny141700Russia

Nonmagnetic impurity scattering is known to shift up the Ginzburg-Landau parameter k of a *** this case,when the system is initially in type I,it can change its magnetic response,crossing the intertype domain with k~1 between the two standard superconductivity types and arriving at type *** the present work we demonstrate that the impact of disorder can be much more profound in the presence of the multiband structure of the charge carrier *** particular,when the band diffusivities differ from each other,the intertype domain tends to expand significantly,including points with k>>1 that belong to deep type-Ⅱ in conventional single-band *** finding sheds light on the nontrivial disorder effect and significantly complements earlier results on the enlargement of the intertype domain in clean multiband superconductors.

关键词： superconductivity disorder intertype superconductivity twoband model

Stability Analysis of DC Microgrid Clusters Based on Step-by-step System Matrix Building Algorithm

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Journal of Modern power Systems and Clean Energy 2024年第3期12卷 900-912页

作者： K.Jithin N.Mayadevi R.Hari Kumar v.p.Mini the Department of Electrical Engineering College of Engineering TrivandrumAPJ Abdul Kalam Technological University(APJAKTU)ThiruvananthapuramIndia

DC microgrids(DCMGs)are made up of a network of sources and loads that are connected by a number of power electronic converters(pECs).The increase in the number of these pECs instigates major concerns in system *** interconnecting the microgrids to form a cluster,the system stability must be *** paper proposes a novel stepby-step system matrix building(SMB)algorithm to update the system matrix of an existing DCMG cluster when a new microgrid is added to the cluster through a distribution *** stability of the individual DCMGs and the DCMG cluster is analyzed using the eigenvalue ***,the particle swarm optimization(pSO)algorithm is used to retune the controller gains if the newly formed cluster is not *** simulation of the DCMG cluster is carried out in MATLAB/Simulink environment to test the proposed *** results are also validated using the Op4510 real-time simulator(RTS).

关键词： Converter DC microgrid cluster eigenvalue interconnection particle swarm optimization system stability system matrix

Wormhole solutions under the effect of dark matter in f(R,L_(m))gravity

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Communications in Theoretical physics 2024年第5期76卷 102-113页

作者： Lakhan v Jaybhaye Moreshwar Tayde pK Sahoo Department of Mathematics Birla Institute of Technology and Science-PilaniHyderabad CampusHyderabad-500078India

In the background of f(R,L_(m))gravity,this work investigates three distinct dark matter halo profiles to test the possibility of generalised wormhole geometry within the galactic halo *** current study aims to accomplish these goals by examining various dark matter profiles including universal rotation curves(URC),Navarro-Frenk-White(NFW)model-Ⅰ,and NFW model-Ⅱinside two distinct f(R,L_(m))gravity *** to the f(R,L_(m))=R/2+L^(a)_(m)model,the dark matter(DM)halo density profiles produce suitable shape functions that meet all the necessary requirements for exhibiting the wormhole geometries with appropriate choice of free *** addition,to examine DM profiles under the f(R,L_(m))=R/2+(1+λR)L_(m) model,we consider a specific shape ***,we observed that the derived solution from both two models violates the null energy constraints,confirming that the DM supports wormholes to maintain in the galactic halo.

关键词： f(R L_(m))gravity wormhole dark matter(Some figures may appear in colour only in the online journal)