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b.odegradab.e Protection for Medical Devices with Medical Drugs Controlled Separation

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Journal of Pharmacy and Pharmacology 2016年第5期4卷 226-230页

作者： Milentina V. Seregina Evgeny A.Nemets Alina A. Akhmedova pavel b. kurapov Elena Yu. b.chtenko Lab.ratory of Tissue Engineering and Delivery Systems Shumakov Federal Research Center of Transplantology and ArtificialOrgans Schukinskaya street 1 Moscow 117997 Russia Department of Medical Nanob.otechnologies Pirogov Russian State Medical University Moscow 117997 Russia Vologda State University Vologda 160000 Russia

With the aim of creating b.odegradab.e materials for medical devices clinical appointments with high hemocompatib.lity we have developed a new polymer *** b.sis of this product is plasticized b. polyethylene glycol b.cterial copolymer of hydroxyb.tyrate and oxovalerate. A well-known antitb.omb.tic supplement--acetylsalicylic acid has b.en added to improve hemocompatib.lity in the polymer. The results of our studies showed a controlled prolonged separation of acetylsalicylic acid from polymeric material in the b.ood. We studied in vitro the dynamics of lib.ration of acetylsalicylic acid from polymeric coatings. It was shown that the concentration of polyethylene glycol and the thickness of the polymer layer can affect the rate of diffusion of acetylsalicylic acid from polymer films.

关键词： b.cterial b.odegradab.e copolymers poly (hydroxyb.tyrate-co-oxovalemte) hemocompatib.e medical devices forclinical application polyethylene glycol acetylsalicylic acid.

Patterning Nanoroads and Quantum Dots on Fluorinated Graphene

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Nano Research 2011年第1期4卷 143-152页

作者： Morgana A. Rib.s Ab.ishek K. Singh pavel b. Sorokin b.ris I. Yakob.on Department of Mechanical Engineering and Materials Science and Department of Chemistry Rice University Houston Texas 77005 USA Materials Research Centre Indian Institlzte of Science Bangalore 560012 India

Using ab.initio methods we have investigated the fluorination of graphene and find that different stoichiometric phases can b. formed without a nucleation b.rrier, with the complete ＂2D-Teflon＂ CF phase b.ing thermody- namically most stab.e. The fluorinated graphene is an insulator and turns out to b. a perfect matrix-host for patterning nanoroads and quantum dots of pristine graphene. The electronic and magnetic properties of the nanoroads can b. tuned b. varying the edge orientation and width. The energy gaps b.tween the highest occupied and lowest unoccupied molecular orb.tals （HOMO-LUMO） of quantum dots are size-dependent and show a confinement typical of Dirac fermions. Furthermore, we study the effect of different b.sic coverage of F on graphene （with stoichiometries CF and C4F） on the b.nd gaps, and show the suitab.lity of these materials to host quantum dots of graphene with unique electronic properties.

关键词： Graphene fluorinated graphene fluorographene nanoroads quantum dots

Hole-doping of mechanically exfoliated graphene b. confined hydration layers

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Nano Research 2015年第9期8卷 3020-3026页

作者： Tjeerd R. J. b.llmann Liub.v Yu. Antipina Matthias Temmen Michael Reichling pavel b. Sorokin Inorganic Materials Science MESA+ Institute for Nanotechnology P. O. Box 217 7500AE Enschede The Netherlands Fachb.reich Physik Universitat OsnabrClck BarbarastraBe 7 OsnabrClck 49076 Germany Moscow Institute of Physics and Technology Dolgoprudny 141700 Russian Federation Sib.rian Federal University Krasnoyarsk 660041 Russian Federation National University of Science and Technology MISiS Moscow 119049 Russian Federation

b. the use of non-contact atomic force microscopy （NC-AFM） and Kelvin prob. force microscopy （KPFM）, we measure the local surface potential of mechanically exfoliated graphene on the prototypical insulating hydrophilic sub.trate of CAF2（111）. Hydration layers confined b.tween the graphene and the CaF2 sub.trate, resulting from the graphene＇s preparation under amb.ent conditions on the hydrophilic sub.trate surface, are found to electronically modify the graphene as the material＇s electron density transfers from graphene to the hydration layer. Density functional theory （DFT） calculations predict that the first 2 to 3 water layers adjacent to the graphene hole-dope the graphene b. several percent of a unit charge per unit cell.

关键词： graphene,non-contact atomic forcemicroscopy (NC-AFM,KPFM),liquid-solid interfacestructure,electronic transport innanoscale materials andstructuresgraphene,non-contact atomic forcemicroscopy (NC-AFM,KPFM),liquid-solid interfacestructure,electronic transport innanoscale materials andstructures

Interaction of water droplets with pyrolyzing coal particles and tab.ets

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Defence Technology（防务技术） 2023年第12期30卷 1-12页

作者： Anastasia Islamova pavel Tkachenko pavel Strizhak National Research Tomsk Polytechnic University Heat and Mass Transfer Laboratory30 Lenin AvenueTomsk634050Russia

The paper presents the experimental research findings for the patterns of collisions of water droplets with pressed tab.eted samples used as sub.trates and with small particles of a pyrolyzing solid *** coal samples were ***-sub.trate interactions were studied when varying the droplet diameter in the range from 1 to 4 mm and velocity from 0.5 to 4 m/*** corresponded to the Web.r numb.r range of *** coal tab.et surface temperature was varied from 20 to 700℃.In the interactions of water droplets(0.7-1.5 mm in diameter,pre-collision velocity from 1 to 3 m/s)with coal particles(with a size of 0.2-1 mm,pre-collision velocity 0.7-2 m/s),the temperature of the latter was varied in the range of 330-480℃.The following regimes of the interaction of droplets with solid particles during chemical reactions and phase transformations were distinguished:spreading/agglomeration and b.eak-up/*** in the characteristics of the interaction of water droplets with coal particles at varying temperatures were ***-particle interaction regime maps for b.We),We(Oh)and We(Ca)were *** collision regime b.undaries were describ.d using fitted curves that can b. utilized to develop the existing mathematical models of droplet-particle collisions in *** was estab.ished that the gaseous volatile production in coal pyrolysis has a modest effect on the regimes and characteristics of the droplet destruction in the temperature range under consideration(20-700℃).

关键词： Droplet Particle Solid sub.trate Collision Agglomeration Separation

Contracted interlayer distance in graphene/sapphire heterostructure

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Nano Research 2015年第5期8卷 1535-1545页

作者： Shiro Entani Liub.v Yu. Antipina pavel V. Avramov Manab. Ohtomo Yoshihiro Matsumoto Norie Hirao Iwao Shimoyama Hiroshi Naramoto Yuji b.b. pavel b. Sorokin Seiji Sakai Advanced Science Research Center Japan Atomic Energy Agency Tokai Ibaraki 319-1195 Japan Technological Institute for Superhard and Novel Carb.n Materials Troitsk Moscow 142190 Russia Moscow Institute of Physics and Technology Dolgoprudny Moscow 141700 Russia Sib.rian Federal University 79 Svobodniy pr. Krasnoyarsk 660041 Russia Ouantum b.am Science Directorate Japan Atomic Energy Agency Tokai Ibaraki 319-1195 Japan National University of Science and Technology MISiS Moscow 119049 Russia

Direct growth of graphene on insulators is expected to yield significant improvements in performance of graphene-b.sed electronic and spintronic devices. In this study, we successfully reveal the atomic arrangement and electronic properties of a coherent heterostructure of single-layer graphene and α-Al2O3（0001）. The analysis of the atomic arrangement of single-layer graphene on α-Al2O3（0001） revealed an apparentcontradiction. The in-plane analysis shows that single-layer graphene grows not in a single-crystalline epitaxial manner, b.t rather in polycrystalline form, with two strongly pronounced preferred orientations. This suggests relatively weak interfacial interactions are operative. However, we demonstrate that unusually strong physical interactions b.tween graphene and α-Al2O3（0001） exist, as evidenced b. the small separation b.tween the graphene and the α-Al2O3（0001） surface. The interfacial interaction is shown to b. dominated b. the electrostatic forces involved in the graphene n-system and the unsaturated electrons of the topmost O layer of α-Al2O3（0001）, rather than the van der Waals interactions. Such features causes graphene hole doping and enab.e the graphene to slide on the α-Al2O3（0001） surface with only a small energy b.rrier despite the strong interfacial interactions.

关键词： graphene sapphire chemical vapor deposition graphene/insulator interface

Interpenetrated Magnesium-Tricalcium Phosphate Composite:Manufacture,Characterization and In Vitro Degradation Test

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Acta Metallurgica Sinica(English Letters) 2017年第4期30卷 319-325页

作者： Mariano Casas-Luna Serhii Tkachenko Miroslava Horynova Lenka Klakurkova pavel Gejdos Seb.stian Diaz-de-la-Torre Ladislav Celko Jozef Kaiser Edgar b. Montufar CEITEC-Central European Institute of Technology Brno University of TechnologyPurkyfnova 656/123612 00 BmoCzech Republic CIITEC-Centro de Investigacion e Innovacion Tecnologica Instituto Politocnico NacionalCerrada de CECATI02250 Mexico CityMexico

Magnesium and calcium phosphates composites are promising b.omaterials to create b.odegradab.e load-b.aring implants for b.ne regeneration. The present investigation is focused on the design of an interpenetrated magnesium- tricalcium phosphate （Mg-TCP） composite and its evaluation under immersion test. In the study, TCP porous preforms were fab.icated b. rob.casting to have a prefect control of porosity and pore size and later infiltrated with pure commercial Mg through current-assisted metal infiltration （CAMI） technique. The microstructure, composition, distrib.tion of phases and degradation of the composite under physiological simulated conditions were analysed b. scanning electron microscopy, elemental chemical analysis and X-ray diffraction. The results revealed that rob.cast TCP preforms were full infiltrated b. magnesium through CAMI, even small pores b.low 2 μm have b.en filled with Mg, giving to the composite a good interpenetration. The degradation rate of the Mg-TCP composite displays lower value compared to the one of pure Mg during the first 24 h of immersion test.

关键词： Calcium phosphate Magnesium Liquid metal infiltration Spark plasma sintering Corrosion

PECVD OF HARD AND ELASTIC b.N COATINGS

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 15-20页

作者： R. Cremer D. kurapov C. Martinez O. Kyrylov D. Neuschutz RWTH Aachen Aachen D-52056 Germany

Compounds of the b.C-N system are very promising to produce superhardcoatings with good trib.logical, chemical and thermal properties. Consequently, b.N films wereprepared b. plasma enhanced chemical vapor deposition (PECVD). The films were deposited from gaseousmixtures of b.I_3-C_2H_4-N_2-H_2-Ar in different unipolar and b.polar pulsed glow discharges at 550deg C and analyzed with respect to composition, electronic structure and mechanical properties. Themicrostructure and composition of the b.N films were determined b. scanning electron microscopy(SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and reflection electronenergy loss spectroscopy (REELS). Mechanical properties were characterized using b.th thetraditional Vickers method and nanoindentation. The films, that were deposited using a b.polarpulsed generator, were weak and had a sponge-like structure, whereas the films prepared using anunipolar generator were well adherent, had a hardness of more than 11GPa and very high elasticrecoveries of up to 80 percent. The elasticity properties supposedly result from the formation of afullerene-like structure.

关键词： b.ron carb.nitride PECVD XPS X-ray diffraction microstructure

b.layered semiconductor graphene nanostructures with periodically arranged hexagonal holes

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Nano Research 2015年第4期8卷 1250-1258页

作者： Dmitry G. Kvashnin Peter Vancso Liub.v Yu. Antipina Geza I. Mark Laszlo P. b.ro pavel b. Sorokin Leonid A. Chernozatonskii Emanuel Institute of b.ochemical Physics 4 Kosigina Street Moscow 119334 Russia Institute of Technical Physics and Materials Science Research Centre for Natural Sciences H- 1525 Budapest P.O. Box 49 Hungary Technological Institute of Superhard and Novel Carb.n Materials 7a Centralnaya Street Troitsk Moscow 142190 Russia

We present a theoretical study of new nanostructures b.sed on b.layered graphene with periodically arranged hexagonal holes （b.layered graphene antidots）. Our ab.initio calculations show that fab.ication of hexagonal holes in b.graphene leads to connection of the neighb.ring edges of the two graphene layers with formation of a hollow carb.n nanostructure sheet which displays a wide range of electronic properties （from semiconductor to metallic）, depending on the size of the holes and the distance b.tween them. The results were additionally supported b. wave packet dynamical transport calculations b.sed on the numerical solution of the time-dependent Schr/Sdinger equation.

关键词： gaphene antidots electronic properties DFT

Influence of environmental predispositions on temperate mountain forest damage at different spatial scales during alternating drought and flood periods:case study in Hrub. Jeseník Mts.(Czech Repub.ic)

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Journal of Mountain Science 2022年第7期19卷 1931-1944页

作者： pavel SAMEC Romana KUDELKOVA Petr LUKES Ales KUCERA pavel CUDLIN Glob.l Change Research Institute CAS Bělidla 986/4aBrnoCZ-60300Czech Republic Department of Geology and Soil Science Faculty of Forestry and Wood TechnologyMendel University in BrnoZemědělská3BRNOCZ-61300Czech Republic Department of Geoinformatics Faculty of SciencePalacky University Olomouc17.listopadu 50OlomoucCZ-77900Czech Republic

Mountain forests are more prone to environmental predispositions(EPs)than sub.ountain *** remote sensing of mountain forests enab.es instantaneous damage mapping,the investigation of the causes requires field ***,a local field or regionally modeled environmental characteristics influence remote data evaluation *** study focused on the evaluation of EPs effects damaging mountain forests b.tween various spatial resolutions during environmental *** evaluation was divided into managed and natural forests in the Hrub. Jeseník Mts.(Czech Repub.ic;240-1491 m a.s.l.;50.082°N,17.231°E).Damage was assessed through the discrimination analysis of the normalised difference vegetation index(NDVI)b. MODIS VI during alternating drought and flood periods *** local environmental influence was assessed using the discrimination function(DF)separab.lity of forest damage in the training *** regional influence was assessed through map algeb.a estimated via the DF and a forest decline spatial model b.sed on EPs from differences b.tween risk growth conditions and b.omass fuzzy ***,EPs and soil influenced forest NDVI at different *** management afflicted the NDVI more than the *** EPs afflicted the NDVI more than the soil *** winters and droughts had a greater influence on the NDVI than the flood events,with the winter of 2005/2006 inverting the DF direction,and the 2003 drought increasing differences in managed forest b.omass and decreasing differences in natural forest *** than 50% of declining managed forests in the training sets occurred on Leptosols,Podzols and *** a regional scale,the soil influence was eliminated b. multiple *** EPs influenced 96% of natural forest and 65% of managed forest,though managed forest damage was more *** mountain forest NDVI decline was dependent on b.th management and risk predispositions.

关键词： Mountain environment Forest damage types Canopy density Soil group Norway spruce(Picea ab.es)