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Advantageous mechanochemical synthesis of copper(Ⅰ)selenide semiconductor,characterization,and properties

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Frontiers of Chemical Science and Engineering 2022年第3期16卷 433-442页

作者： Katarína Gáborová marcela Achimovičová michal Hegedüs Vladimír Girman mária Kaňuchová Erika Dutková Institute of Geotechnics Slovak Academy of SciencesKošice04001Slovakia Institute of metallurgy 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 mill.The kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se mixtures.The X-ray diffraction confirmed the orthorhombic crystal structure of Cu_(2)Se with the crystallite size∼25 nm.The surface chemical structure was studied by X-ray photoelectron spectroscopy,whereby the binding energy of the Cu 2p and Se 3d signals corresponded to Cu^(+)and Se^(2−)oxidation states.Transmission electron microscopy revealed agglomerated nanocrystals and confirmed their orthorhombic structure,as well.The optical properties were studied utilizing ultraviolet-visible spectroscopy and photoluminescence spectroscopy.The direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size effect.This type of Cu_(2)Se synthesis can be easily adapted to production dimensions using an industrial vibratory mill.The advantages 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

Sc元素添加对双辊铸轧Al−Cu−Li−mg−Zr基合金热处理的影响

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Transactions of Nonferrous metals Society of China 2024年第6期34卷 1759-1773页

作者： Rostislav KRÁLÍK Barbora KŘIVSKÁ Lucia BAJTOŠovÁ mykhailo STOLBCHENKO mirko SCHAPER Olexandr GRYDIN miroslav CIESLAR Department of Physics of materials Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116PragueCzech Republic Department of materials Science Faculty of Mechanical EngineeringUniversity of PaderbornWarburger Straße 10033098PaderbornGermany

提出制备含Sc的Al−Cu−Li−mg−Zr基合金带材的工艺方案。即先采用双辊铸轧技术制备近净形状的3 mm厚带材,再对其进行均匀化/固溶处理。研究两种Al−Cu−Li−mg−Zr基双辊铸轧合金,其中一种添加质量分数为0.17%的Sc,另一种未添加Sc。两种合金... 详细信息

提出制备含Sc的Al−Cu−Li−mg−Zr基合金带材的工艺方案。即先采用双辊铸轧技术制备近净形状的3 mm厚带材,再对其进行均匀化/固溶处理。研究两种Al−Cu−Li−mg−Zr基双辊铸轧合金,其中一种添加质量分数为0.17%的Sc,另一种未添加Sc。两种合金均先在300℃下退火30 min,然后在450℃下退火30 min以及530℃下退火30 min,随后进行室温水淬。前两段退火后组织中生成了细小、弥散的Al_(3)Zr/Al_(3)(Sc,Zr)颗粒。最后的退火步骤起到了均匀化/固溶处理的作用。双辊铸轧材料的细小晶粒结构使含有主要合金元素的原始颗粒在较短的退火时间内溶解。缩短保温时间可以限制表面层中Li的耗尽和Al_(3)Zr/Al_(3)(Sc,Zr)弥散相的明显粗化。铸态含Sc材料已经具有明显细小的晶粒结构,而经均匀化/固溶处理后生成的Al_(3)(Sc,Zr)弥散相抑制了晶粒在高温下发生粗化。在后续180℃下时效处理后,形成了θʹ(Al_(2)Cu)、T1(Al_(2)CuLi)和S'(Al_(2)Cumg)强化相。在峰值时效状态下,屈服强度提高了200 mPa,这一数值与类似直接冷却铸造材料的相当,从而证实了所提方案的合理性。

关键词：显微组织力学性能 Al−Cu−Li基合金 Sc合金化双辊铸轧

Predicting the output error of the suboptimal state estimator to improve the performance of the mPC-based artificial pancreas

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Control Theory and Technology 2023年第4期21卷 541-554页

作者： martin Dodek Eva miklovičová Institute of Robotics and Cybernetics Faculty of Electrical Engineering and Information TechnologySlovak University of Technology in BratislavaIlkovičova 3Bratislava81219Slovakia

The error of single step-ahead output prediction is the information traditionally used to correct the state estimate while exploiting the new measurement of the system output.However,its dynamics and statistical properties can be further studied and exploited in other ways.It is known that in the case of suboptimal state estimation,this output prediction error forms a correlated sequence,hence it can be effectively predicted in real time.Such a suboptimal scenario is typical in applications where the process noise model is not known or it is uncertain.Therefore,the paper deals with the problems of analytical and empirical modeling,identification,and prediction of the output error of the suboptimal state estimator for the sake of improving the output prediction accuracy and ultimately the performance of the model predictive control.The improvements are validated on an empirical model of type 1 diabetes within an in-silico experiment focused on glycemia prediction and implementation of the mPC-based artificial pancreas.

关键词： Suboptimal state estimation Prediction Autoregressive model moving average model model predictive control Diabetes mellitus Artificial pancreas

ImEX Large 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： Georgij 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 IGPm RWTH AachenGermany.

We present new large time step methods for the shallow water flows in the lowFroude number limit.In order to take into accountmultiscale phenomena that typically appear in geophysical flows nonlinear fluxes are split into a linear part governing the gravitational waves and the nonlinear advection.We propose to approximate fast linear waves implicitly in time and in space bymeans of a genuinely multidimensional evolution operator.On the other hand,we approximate nonlinear advection part explicitly in time and in space bymeans of themethod of characteristics or some standard numerical flux function.Time integration is realized by the implicit-explicit(ImEX)method.We apply the ImEX Euler scheme,two step Runge Kutta Cranck Nicolson scheme,as well as the semi-implicit BDF scheme and prove their asymptotic preserving property in the low Froude number limit.Numerical experiments demonstrate stability,accuracy and robustness of these new large time step finite volume schemes with respect to small Froude number.

关键词： LowFroude number flows asymptotic preserving schemes shallowwater equations large time step semi-implicit approximation evolution Galerkin schemes

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

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Journal of materials Science & Technology 2010年第5期26卷 454-460页

作者： Daniela Kladeková Renáta Orináková Annamária Krajníková miriam Kupková margita 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） coatings 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 out.The electrochemical polymerization treatment was performed in a fluidized bed electrolyzer using sulphuric acid solution containing potassium persulphate and methyl methacrylate（mmA）.The surface topography 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

Biotechnological preparation of chicken skin gelatine using factorial design of experiments

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Food Bioscience 2022年第3期47卷 898-907页

作者： Petr mrázek Robert Gál Pavel mokrejš Jana Orsavová Dagmar Janáčová Tomas Bata University in Zlín Department of Polymer EngineeringVavrečkova 275760 01ZlínCzech Republic Tomas Bata University in Zlín Department of Food TechnologyMostní 5139760 01ZlínCzech Republic Tomas Bata University in Zlín Language CentreŠtefánikova 5670760 01ZlínCzech Republic Tomas Bata University in Zlín Department of Automation and Control EngineeringNad Stráněmi 4511760 01ZlínCzech Republic

Poultry meat production steadily increases and its by-products including legs or skins may be further utilized to prepare gelatine,generally by using alkali or acid substances.Since they are toxic,different methods are desirable,e.***.applying proteolytic enzymes.Using enzymes is beneficial as they shorten processing time and reduce the required water amount.Processing conditions(the enzyme amount during the pre-treatment,first and second extraction temperature and time)of the process may influence gelatine quality and its yield.In this study,gelatines were prepared from chicken skin at different conditions in the series of combined factorial design of experiments.The significance of the influence of the conditions on the quality(gel strength,viscosity,melting and gelling point)and yield of chicken skin gelatine(CSG)was observed.The highest yield(31.5%)was obtained at the conditions of the enzyme amount of 0.8%,first extraction temperature 80℃ and time 30 min,second extraction temperature 90℃ and time 60 min.Furthermore,the highest CSG quality of gel strength(190 Bloom),viscosity(4.06 mPas),melting point(38.3℃)and gelling point(20.5℃)was obtained at the conditions of 0.2%/50℃/30 min in the first extraction.

关键词： Collagen Chicken skin Enzyme pre-treatment Gelatine Gelling properties

High-resolution genome-wide association study of a large Czech collection of sweet cherry (Prunus avium L.) on fruit maturity and quality traits

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Horticulture Research 2023年第1期10卷 113-127页

作者： Kateřina Holušová JanaČmejlová Pavol Suran RadekČmejla JiříSedlák Lubor Zelený Jan Bartoš Centre of the Region Hanáfor Biotechnological and Agricultural Research Institute of Experimental Botany of the Czech Academy of Sciencesšlechtitelu 31Olomouc77900Czech Republic Research and Breeding Institute of Pomology Holovousy Ltd. Holovousy 129Holovousy50801Czech Republic

In sweet cherry(Prunus avium L.),quantitative trait loci have been identified for fruit maturity,colour,firmness,and size to develop markers for marker-assisted selection.However,resolution is usually too low in those analyses to directly target candidate genes,and some associations are missed.In contrast,genome-wide association studies are performed on broad collections of accessions,and assemblies of reference sequences from Tieton and Satonishiki cultivars enable identification of single nucleotide polymorphisms after whole-genome sequencing,providing high marker density.Two hundred and thirty-five sweet cherry accessions were sequenced and phenotyped for harvest time and fruit colour,firmness,and size.Genome-wide association studies were used to identify single nucleotide polymorphisms associated with each trait,which were verified in breeding material consisting of 64 additional accessions.A total of 1767106 single nucleotide polymorphisms were identified.At that density,significant single nucleotide polymorphisms could be linked to co-inherited haplotype blocks(median size∼10 kb).Thus,markers were tightly associated with respective phenotypes,and individual allelic combinations of particular single nucleotide polymorphisms provided links to distinct phenotypes.In addition,yellow-fruit accessions were sequenced,and a∼90-kb-deletion on chromosome 3 that included five mYB10 transcription factors was associated with the phenotype.overall,the study confirmed numerous quantitative trait loci from bi-parental populations using high-diversity accession populations,identified novel associations,and genome-wide association studies reduced the size of trait-associated loci from megabases to kilobases and to a few candidate genes per locus.Thus,a framework is provided to develop molecular markers and evaluate and characterize genes underlying important agronomic traits.

关键词： fir breeding maturity

原位透射电镜研究双辊铸造AA8079铝合金的均匀化过程

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Transactions of Nonferrous metals Society of China 2022年第7期32卷 2138-2149页

作者： R.KRÁLÍK B.KŘIVSKÁ L.BAJTOŠovÁ m.ŠLAPÁKovÁ m.CIESLAR Faculty of mathematics and Physics Charles UniversityKe Karlovu 312116 Prague 2Czechia

AA8079铝合金是一种常用的制造薄包装箔的胚料,其主要的合金化元素Fe和Si可以形成二元和三元金属间化合物。采用原位透射电镜模拟铸态材料均匀化退火,分析这些颗粒的形状、类型和分布的实时变化,它们影响最终产品的力学性能、材料对形... 详细信息

AA8079铝合金是一种常用的制造薄包装箔的胚料,其主要的合金化元素Fe和Si可以形成二元和三元金属间化合物。采用原位透射电镜模拟铸态材料均匀化退火,分析这些颗粒的形状、类型和分布的实时变化,它们影响最终产品的力学性能、材料对形成气孔和其他宏观缺陷的敏感性。对另一组铸态样品在模拟工业热处理制度范围内进行退火处理,并结合电阻率测量,验证原位试验的结果。结果表明,在450℃以上的原始颗粒球化、475℃的新颗粒成核、525℃以上的颗粒粗化以及550℃以上的原始颗粒完全溶解等几个阶段发生了回复、基体去饱和以及相变,且具有明显的温度区间。

关键词：铝合金原位退火均匀化箔胚料

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

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Integrative Zoology 2019年第6期14卷 561-575页

作者： John BUCKERIDGE TomášKOČÍ Ján SCHLÖGL Adam TOmAŠovÝCH martina KOČovÁVESELSKÁ Earth&Oceanic Systems Group RMIT UniversityMelbourneVictoriaAustralia Ivančická581 PragueCzech Republic and Palaeontological DepartmentNatural History MuseumNational MuseumPragueCzech Republic Department of Geology and Paleontology Comenius University in BratislavaBratislavaSlovakia Institute of Earth Sciences Slovak Academy of SciencesBratislavaSlovakia Department of Paleobiology and Paleoecology 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 complex.The 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 Caledonia.The cirripedes have left both cemented calcareous bases of Hexelasma and scars associated with bioerosion and discoloration produced by verrucomorph barnacles.Live cirripedes included a metaverruca recta,with articulated opercular plates and organic 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 shell.The disposition of verrucomorphs indicates that most Nautilus shells were colonized post-mortem rather than during a floating stage.However,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 Nautilus.The degree 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 degraded shells.Traces made by verrucomorphs described here are ellipsoidal and a new ichnotaxon,Anellusichnus ellipticus,is proposed to accommodate them.Importantly,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