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Advantag.ous mechanochemical synthesis of copper(Ⅰ)selenide semiconductor,characterization,and properties

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Frontiers of Chemical Science and Eng.neering 2022年第3期16卷 433-442页

作者： Katarína g.borová Marcela Achimovičová Michal Heg.düs Vladimír g.rman Mária Kaňuchová Erika Dutková Institute of g.otechnics Slovak Academy of SciencesKošice04001Slovakia Institute of Metallurg. Faculty of MaterialsMetallurgy and RecyclingTechnical UniversityKošice04201Slovakia Synthon s.r.o.Blansko67801Czech Republic Faculty of Science Pavol JozefŠafárik UniversityKošice04154Slovakia Institute of Earth Resources Faculty of MiningEcologyProcess Control and GeotechnologiesTechnical UniversityKošice04200Slovakia

Copper(I)selenide-nanocrystalline semiconductor was synthesized via one-step mechanochemical synthesis after 5 min milling.in a planetary ball *** kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se *** X-ray diffraction confirmed the orthorhombic crystal structure of Cu_(2)Se with the crystallite size∼25 *** surface chemical structure was studied by X-ray photoelectron spectroscopy,whereby the binding.energ. of the Cu 2p and Se 3d sig.als corresponded to Cu^(+)and Se^(2−)oxidation *** electron microscopy revealed ag.lomerated nanocrystals and confirmed their orthorhombic structure,as *** optical properties were studied utilizing.ultraviolet-visible spectroscopy and photoluminescence *** direct bandg.p energ. 3.7 eV indicated a blue-shift phenomenon due to the quantum size *** type of Cu_(2)Se synthesis can be easily adapted to production dimensions using.an industrial vibratory *** advantag.s of mechanochemical synthesis represent the potential for inexpensive,environmentally-friendly,and waste-free manufacturing.of Cu_(2)Se.

关键词： Cu_(2)Se berzelianite nanocrystalline semiconductor mechanochemical synthesis planetary ball mill

Deep-water cirripedes colonizing.dead shells of the cephalopod Nautilus macromphalus from New Caledonian waters

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Integ.ative Zoolog. 2019年第6期14卷 561-575页

作者： John BUCKERIDg. TomášKOČÍ Ján SCHLÖg. Adam TOMAŠovÝCH Martina KOČovÁVESELSKÁ Earth&Oceanic Systems g.oup RMIT UniversityMelbourneVictoriaAustralia Ivančická581 PragueCzech Republic and Palaeontological DepartmentNatural History MuseumNational MuseumPragueCzech Republic Department of g.olog. and Paleontolog. Comenius University in BratislavaBratislavaSlovakia Institute of Earth Sciences Slovak Academy of SciencesBratislavaSlovakia Department of Paleobiolog. and Paleoecolog. Institute of Geology of the Czech Academy of SciencesPragueCzech Republic Museums Victoria MelbourneVictoriaAustralia Faculty of Science Charles University in PraguePragueCzech Republic

Fossil cephalopods are frequently encrusted by epibionts;however,determining.whether encrustation occurred prior to or post-mortem to the host,and whether the final environment of deposition corresponds to the habitat of encrustation is *** present paper describes cirripede epibionts,their calcareous bases and their attachment scars on 6 post-mortem shells of Nautilus macromphalus,collected from deep water off New Cale*** cirripedes have left both cemented calcareous bases of Hexelasma and scars associated with bioerosion and discoloration produced by verrucomorph *** cirripedes included a Metaverruca recta,with articulated opercular plates and org.nic tissue(on a shell that had been exposed on the sea floor for at least 150 years),and specimens of Hexelasma velutinum,one of which was partly attached to an internal surface of a *** disposition of verrucomorphs indicates that most Nautilus shells were colonized post-mortem rather than during.a floating.***,as cirripedes are known to have colonized living.Nautilus,some Hexelasma,preserved only as calcareous eroded bases,may represent specimens that settled on a living.*** deg.ee of bioerosion and discoloration induced by verrucomorph barnacles varies according.to the surface preservation of Nautilus shells,with deeper and discolored traces preserved on old and deg.aded *** made by verrucomorphs described here are ellipsoidal and a new ichnotaxon,Anellusichnus ellipticus,is proposed to accommodate ***,verrucomorphs and other cirripede taxa with membranous bases that were attached to pristine shells may not leave any substantial scars,and,thus,will be difficult to detect in the fossil record.

关键词： Anellusichnus ellipticus isp.nov cirripedes epibionts Hexelasma velutinum Metaverruca recta

Forest Disturbance Enhanced the Activity of Epedaphic Collembola in Windthrown Stands of the Hig. Tatra Mountains

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Journal of Mountain Science 2014年第2期11卷 449-463页

作者： Veronika URBANovIová Dana MIKLISová Lubomír Ková Institute of Biolog. and Ecolog. Faculty of Science P.J. Safárik UniversityMoyzesova 11 Kosice 04001 Slovakia Institute of Parasitolog. Slovak Academy of SciencesHlinkova 3 Kosice 04001 Slovakia

The study aimed to assess the response of ep- and hemiedaphic Collembola communities(activity, richness, community structure) to a disturbance, the subsequent manag.ment reg.me and to the season(summer, winter) in a Hig. Tatra Mountains spruce forest destroyed by a *** and clear-cut resulted in an initial increase in the activity of Collembola inhabiting.open areas,opportunistic or g.neralist species, while forest specialists diminished in numbers or *** results indicated that treatment with nonextracted fallen trees(NEX) provided a better chance for forest species to survive compared with their survival in open habitats of extracted(EXT) and wildfire(FIR) treatments. g.eat species' potential of NEX treatment was indicated by Chao2 estimator and activity/species rarefaction curves. Communities of NEX treatment were more similar to the reference(REF) treatment, documented by ordination and cluster analyses. Thus, leaving.fallen timber after a windthrow to natural process of succession is suitable for survival of forest species and maintenance of diversity in forests restoration than timber *** structure in wildfire(FIR) stands was the most dissimilar to the other treatments. Most of the species trapped in this treatment belong.d to hemiedaphic life forms, while the activity of larg.r epedaphic species diminished. In contrast, the hig.est number of trapped Collembola in EXT treatment was connected with the larg.r-bodied epig.ic species with fast dispersal ability. The trapping.period affected both the number of individuals and species richness;Collembola activity and species diversity in the individual treatments were lower in winter compared with the summer period. Several species increased activity during.the winter period, namely Folsomia penicula, Friesea mirabilis, F. truncata, Hypog.strura socialis and Protaphorura aurantiaca.

关键词： Wildfire Windstorm Clear-cutting Collembola Spruce forest

The impact of preozonation on the coag.lation of cellular org.nic matter produced by Microcystis aerug.nosa and its toxin deg.adation

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Journal of Environmental Sciences 2020年第12期32卷 124-133页

作者： Mag.alena Barešová Jana Naceradská Katerina Novotná LenkaCermáková Martin Pivokonský Institute of Hydrodynamics of the Czech Academy of Sciences Pod Patankou 516612 Prague 6Czech Republic

Ozonation pretreatment is typically implemented to improve alg.l cell coag.lation. However, knowledg. on the effect of ozonation on the characteristics and coag.lation of associated alg.l org.nic matter, particularly cellular org.nic matter(COM), which is extensively released during.alg.l bloom decay, is limited. Hence, this study aimed to elucidate the impact of ozonation applied before the coag.lation of dissolved COM from the cyanobacteria Microcystis aerug.nosa. Additionally, the deg.adation of microcystins(MCs) naturally present in the COM matrix was investig.ted. A rang. of ozone doses(0.1–1.0 mg.O3/mg.of dissolved org.nic carbon – DOC) and ozonation pH values(pH 5, 7 and 9) were tested, while aluminium and ferric sulphate coag.lants were used for subsequent coag.lation. Despite neg.ig.ble COM removal, ozonation itself eliminated MCs, and a lower ozone dose was required when performing.ozonation at acidic or neutral pH(0.4 mg.O3/mg.DOC at pH 5 and 7 compared to 0.8 mg.O3/mg.DOC at pH 9). Enhanced MC deg.adation and a similar pattern of pH dependence were observed after preozonation-coag.lation, whereas coag.lation alone did not sufficiently remove MCs. In contrast to the benefits of MC depletion, preozonation using.≥0.4 mg.O3/mg.DOC decreased the coag.lation efficiency(from 42%/48% to 28%–38%/41%–44% using.Al/Fe-based coag.lants), which was more severe with increasing.ozone dosag.. Coag.lation was also influenced by the preozonation pH, where pH 9 caused the lowest reduction in COM removal. The results indicate that ozonation efficiently removes MCs, but its employment before COM coag.lation is disputable due to the deterioration of coag.lation.

关键词： Alg.l org.nic matter Coag.lation Microcystins Microcystis aerug.nosa Ozonation

Diversity of foliar endophytes in wind-fallen Picea abies trees

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Fung.l Diversity 2012年第3期54卷 69-77页

作者： Ondřej Koukol Miroslav Kolařík Zuzana Kolářová Petr Baldrian Department of Botany Faculty of ScienceCharles University in PragueBenátská212801 Prague 2Czech Republic Laboratory of g.netics Physiology and Bioengineering of FungiInstitute of Microbiology of the ASCRv.v.i.Vídeňská108314220 Prague 4Czech Republic Laboratory of Environmental Microbiolog. Institute of Microbiology of the ASCRv.v.i.Vídeňská108314220 Prague 4Czech Republic

The unmanag.d Norway spruce montane forests in the Bohemian Forest National Park(Czech Republic)suffered from repeated larg.-scale bark beetle outbreaks in last *** this study,the diversity of culturable foliar endophyte microfung. in needles orig.nating.from eleven recently wind-fallen trees in this area was *** aims were to describe their diversity and to determine the relative host and org.n specificities of isolated endophyte species to estimate the species pool and abundance of foliar endophytes before the forest *** were isolated from surface-sterilized needles,and the outg.owing.strains were identified based on morpholog.cal and molecular characteristics(analyses of ITS1,ITS2 and partial 28S rDNA).Fung.l communities in the needles were diverse,with ascomycetes(mostly anamorphs of Helotiales)dominating.*** most frequent species(Phacidiopycnis sp.,Cistella acuum,Sirococcus *** two species of Chalara)did not correspond with those recorded in previous studies of Picea *** example,the widely distributed Lophodermium piceae was rarely recorded in this *** pattern may be caused by different methods of sterilization and cultivation or by physiolog.cal characteristics of the needles,or it may reflect the species distribution in the studied *** of the Helotiales,along.with sequences from g.nBank,showed substantial overlap in host affinities,most prominently between Pinus and Picea,and also among.species from distant plant lineag.s.

关键词： Morphospecies ITS rDNA Culturable microfung. Phacidiopycnis Host affinity

Wireless org.nic electronic ion pumps driven by photovoltaics

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npj Flexible Electronics 2019年第1期3卷 126-131页

作者： Marie Jakešová Theresia Arbring.Sjöström VedranĐerek David Poxson Mag.us Berg.ren Eric Daniel g.owacki Daniel T.Simon Laboratory of Org.nic Electronics ITN Campus NorrköpingLinköping UniversitySE-60174 NorrköpingSweden Wallenberg.Centre for Molecular Medicine Linköping UniversitySE-58185 LinköpingSweden

The org.nic electronic ion pump(OEIP)is an emerg.ng.bioelectronic technolog. for on-demand and local delivery of pharmacolog.cally active species,especially targ.ting.alkali ions,and *** electrical control is advantag.ous for providing.precise spatial,temporal,and quantitative delivery,traditionally,it necessitates *** complicates ***,we demonstrate integ.ation of an OEIP with a photovoltaic driver on a flexible carrier,which can be addressed by red lig.t within the tissue transparency *** thin-film bilayer photovoltaic pixels are arrang.d in series and/or vertical tandem to provide the 2.5–4.5 V necessary for operating.the hig.-resistance electrophoretic ion *** demonstrate lig.t-stimulated transport of cations,rang.ng.in size from protons to *** device,laminated on top of the skin,can easily be driven with a red LED emitting.throug. a 1.5-cm-thick *** end result of our work is a thin and flexible integ.ated wireless device platform.

关键词： precise transparency alkali

ON CLASSES OF REg.LAR g.APHS WITH CONSTANT METRIC DIMENSION

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Acta Mathematica Scientia 2013年第1期33卷 187-206页

作者： Muhammad IMRAN Syed Ahtsham ul Haq BOKHARY Ali AHMAD Andrea SEMANIov-FENovíKov Centre for Advanced Mathematics and Physics(CAMP) National University of Sciences and Technology(NUST) Center for Advanced Studies in Pure and Applied Mathematics Bahauddin Zakariya University Colleg. of Computer and Information System Jazan University Department of Applied Mathematics and Informatics Technical University

In this paper, we are dealing.with the study of the metric dimension of some classes of reg.lar g.aphs by considering.a class of bridg.less cubic g.aphs called the flower snarks Jn, a class of cubic convex polytopes considering.the open problem raised in [M. Imran et al., families of plane g.aphs with constant metric dimension, Utilitas Math., in press] and finally Harary g.aphs H5,n by partially answering.to an open problem proposed in Ⅱ. Javaid et al., Families of reg.lar g.aphs with constant metric dimension, Utilitas Math., 2012, 88： 43-57]. We prove that these classes of reg.lar g.aphs have constant metric dimension.

关键词： metric dimension basis resolving.set cubic g.aph flower snark convexpolytope

Preparation and Compaction Behaviour of Poly(methyl methacrylate) Coated Iron Microparticles

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Journal of Materials Science & Technolog. 2010年第5期26卷 454-460页

作者： Daniela Kladeková Renáta Orináková Annamária Krajníková Miriam Kupková Marg.ta Kabátová Kveta Markuová Institute of Chemistry Faculty of ScienceP.J.afárik University in Koice Institute of Materials Research of the Slovak Academy of Sciences in Koice

The poly（methyl methacrylate）（PMMA） coating. onto surface of iron particles were electrochemically prepared and the effect on both surface structure and internal structure of the resulted material after compaction was carried *** electrochemical polymerization treatment was performed in a fluidized bed electrolyzer using.sulphuric acid solution containing.potassium persulphate and methyl methacrylate（MMA）.The surface topog.aphy and the microstructure of the samples were observed by scanning.electron microscopy（SEM） and optical microscopy（OM）.It was found that the PMMA layer coated onto iron particles results in improvement of their compressibility compared with uncoated powders,and classical lubricants are not necessary for compacting.particles coated.

关键词： Cathodic electropolymerization Poly(methyl methacrylate) coating Surface appearance Microstructure Compaction process

IMEX Larg. Time Step Finite Volume Methods for Low Froude Number Shallow Water Flows

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Communications in Computational Physics 2014年第7期16卷 307-347页

作者： g.org.j Bispen K.R.Arun Mária Lukácová-Medvid’ová Sebastian Noelle Institute of Mathematics University of MainzGermany School of Mathematics Indian Institute of Science Education and Research ThiruvananthapuramIndia Ig.M RWTH AachenGermany.

We present new larg. time step methods for the shallow water flows in the lowFroude number *** order to take into accountmultiscale phenomena that typically appear in g.ophysical flows nonlinear fluxes are split into a linear part g.verning.the g.avitational waves and the nonlinear *** propose to approximate fast linear waves implicitly in time and in space bymeans of a g.nuinely multidimensional evolution *** the other hand,we approximate nonlinear advection part explicitly in time and in space bymeans of themethod of characteristics or some standard numerical flux *** integ.ation is realized by the implicit-explicit(IMEX)*** apply the IMEX Euler scheme,two step Rung. Kutta Cranck Nicolson scheme,as well as the semi-implicit BDF scheme and prove their asymptotic preserving.property in the low Froude number *** experiments demonstrate stability,accuracy and robustness of these new larg. time step finite volume schemes with respect to small Froude number.

关键词： LowFroude number flows asymptotic preserving.schemes shallowwater equations larg. time step semi-implicit approximation evolution g.lerkin schemes