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Photoluminescence control by hyperbolic metamaterials and metasurfaces:a review

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Opto-Electronic Advances 2021年第8期4卷 30-56页

作者： Leonid Yu.Beliaev Osamu Takayama pavel n.melentiev Andrei V.Lavrinenko DTU Fotonik-Department of Photonics Engineering Technical University of Denmark0rsteds Plads 343DK-2800 Kgs.LyngbyDenmark Institute of Spectroscopy RAS Moscow 108840Russia Higher School of Economics National Research UniversityMoscow 101000Russia

Photolu min esce nee in clud ing fluoresce nee plays a great role in a wide variety of applicati ons from biomedical sensing and imag ing to optoelectr on ***,the enhan ceme nt and con trol of photolu min esce nee has imme nse impact on both fun dame ntal scie ntific research and aforeme nti oned applicati *** various nano phot tonic schemes and nanostructures to enhance the photoluminescence,we focus on a certain type of nanostructures,hyperbolic metamaterials(HMMs).HMMs are highly ani sotropic metamaterials,which produce intense localized electric ***,HMMs n aturally boost photolu min esce nee from dye molecules,qua ntum dots,n itroge n-vaca ncy cen ters in diam on ds,perovskites and tra nsiti on metal dichalcoge *** provide an overview of various con figuratio ns of HMMs,i nclud ing metal-dielectric multilayers,trenches,metallic nanowires,and cavity structures fabricated with the use of noble metals,transparent conductive oxides,and refractory metals as plasmonic *** also discuss lasing action realized with HMMs.

关键词： fluorescence metamaterials metasurfaces Purcell effect nanophotonics hyperbolic metamaterials

Analysis of the Water Film Behavior and its Breakup on Profile using Experimental and numerical Methods

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Journal of Thermal Science 2014年第4期23卷 325-331页

作者： Tomas MUZIK pavel SAFARIK Antonín TUCEK TechSoft Engineering Na Pankraci 2614000 PragueCzech Republic CTU in Prague Department of Fluid Dynamics and ThermodynamicsTechnicka 416607 PragueCzech Republic

This paper deals with the description of water film behaviour on the airfoil nACA0012 using experimental and numerical methods. Properties of the water film on the profile and its breakup into droplets behind the profile are investigated in the aerodynamic tunnel and using CFD methods. The characteristic parameters of the water film, like its thickness and shape for different flow modes are described. Hereafter are described droplets drifted by the air, which water film is broken behind the profile.

关键词： nACA0012 profile water film droplets breakup CFD

Discrete Maximum Principle for Poisson Equation with Mixed Boundary Conditions Solved by hp-FEM

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Advances in Applied Mathematics and Mechanics 2009年第2期1卷 201-214页

作者： Tomáš Vejchodský pavel Šolín Institute of Mathematics Czech Academy of SciencesŽitná25CZ-11567 Praha 1Czech Republic Department of Mathematics and Statistics University of NevadaRenoUSAInstitute of ThermomechanicsCzech Academy of SciencesDolejˇskova 5Praha 8CZ-18200Czech Republic

We present a proof of the discrete maximum principle(DMP)for the 1D Poisson equation−u"=f equipped with mixed Dirichlet-neumann boundary *** problem is discretized using finite elements of arbitrary lengths and polynomial degrees(hp-FEM).We show that the DMP holds on all meshes with no limitations to the sizes and polynomial degrees of the elements.

关键词： Discrete maximum principle hp-FEM Poisson equation mixed boundary conditions

Unrecognized diversity in new Guinean crayfish species (Decapoda, Parastacidae): The evidence from molecular data

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Integrative Zoology 2016年第6期11卷 457-468页

作者： Martin BLÁHA Jiří PATOKA pavel KOZÁK Antonín KOUBA Faculty of Fisheries and Protection of Waters South Bohemian Research Center of Aquaculture and Biodiversity of HydrocenosesUniversity of South Bohemia inČeskéBudějoviceVodňanyCzech Republic Department of Zoology and Fisheries Faculty of AgrobiologyFood and Natural ResourcesCzech University of Life Sciences PraguePrahaCzech Republic

The phylogenetic relationships among imported ornamental crayfish belonging to the genus Cherax were inferred from a combined dataset of 3 mitochondrial genes(COI,16S and 12S)and by comparison with available GenBank sequences of 14 Cherax ***,the concordance of previously described species obtained from a wholesaler(Cherax boesemani,*** and ***)with available GenBank sequences was verified based on COI with special respect to comparison with sequences assigned as Cherax ***cently described species ***,*** and *** belong to the northern group of Cherax *** and analysis with other GenBank COI sequences show previously unreported diversity of new Guinean species,suggesting 5 putative new ***,species assigned to the subgenus Astaconephrops do not form a monophyletic clade;this subgenus should be reappraised relative to the purported typical morphological characteristic of the uncalcified patch on male *** importation of crayfish underscores the importance of accurate species *** of basic molecular methods is a necessary requisite for documenting occurrence,abundance and population trends of target ***,it helps to support eventual conservation decision-making by stakeholders.

关键词： Cherax cytochrome c oxidase DnA barcoding mitochondrial DnA ornamental crayfish

Scalable nanocomposite parylene-based memristors:Multifilamentary resistive switching and neuromorphic applications

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nano Research 2023年第2期16卷 3207-3214页

作者： Anna n.Matsukatova Artem Yu.Vdovichenko Timofey D.Patsaev pavel A.Forsh pavel K.Kashkarov Vyacheslav A.Demin Andrey V.Emelyanov national Research Centre“Kurchatov Institute” Moscow 123182Russia Physics Department Lomonosov Moscow State UniversityMoscow 119991Russia Moscow Institute of Physics and Technology DolgoprudnyjMoscow oblast 141701Russia Enikolopov Institute of Synthetic Polymeric Materials Russian Academy of SciencesMoscow 117993Russia Physics Department Saint Petersburg State UniversitySt.Petersburg 199034Russia

Memristors are promising candidates for synapse emulation in brain-inspired neuromorphic computing *** main obstacle to their usage in such systems is high variability of memristive characteristics and its severe negative effect on the neural network *** paper addresses the issue from two points of view on the example of the parylene-based memristors:(i)the methods of the memristor internal stochasticity decrease and(ii)the methods of the memristive neural network architecture *** introduction of an optimal Ag nanoparticle concentration(3 vol.%–6 vol.%)to the memristive structure leads to a statistically significant decrease in the switching voltage variation and endurance ***,it is shown that post-fabrication annealing improves memristive characteristics,e.g.,resistive switching window increases by an order of magnitude and exceeds 106,the switching voltage variation decreases by a factor of 2(down to 7%for the set and 17%for the reset voltage),and thermostability is *** transmission electron microscopy and impedance spectroscopy analysis allowed establishing a multifilamentary resistive switching mechanism for nanocomposite parylene-based *** simulation of the formal neural network based on these memristors demonstrates high classification accuracy with low variation for an important biomedical task,heart disease prediction,after careful feature selection and network architecture *** prospects of the controlled incorporation of the nanocomposite parylene-based memristors in neural networks are brightened by their scaling possibility in crossbar geometry.

关键词： memristor resistive switching neuromorphic computing parylene nanocomposite

Mathematical Modeling of Heat Transfer Processes of Coal Waste Combustion in a Chamber of Automated Energy Generating Complex

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Journal of Thermal Science 2013年第2期22卷 174-179页

作者： Sergey P. Mochalov Sergey n. Kalashnikov pavel S. Mochalov Guolin Song Guoyi Tang Siberian State Industrial University Advanced Materials Institute Graduate School at ShenzhenTsinghua University

The automated energy generating complex allows obtaining heat energy from waste coal-water slurry fuel （WCF） that is a mixture of fine coal particles from coal enrichment wastes with water. The mixture is blown into the swirl chamber under the pressure through the special sprayers. The received heat energy is used in different ways. One of the important issues is to estimate the heat losses through the walls of this chamber. In this paper we solved the boundary problem of mathematical physics to estimate the temperature fields in the walls of the swirl chamber. The obtained solution allows us to estimate the heat losses through the waUs of the swid chamber. The task of the mathematical physics has been solved by a numerical finite-difference method. The method for solving this prob- lem can be used in the calculation of temperature fields and evaluation of heat losses in other thermal power units.

关键词： heat transfer heat conduction equation boundary conditions the heat transfer coefficient tempera-ture distribution.

Comparing the removal of polycyclic aromatic hydrocarbons in soil after different bioremediation approaches in relation to the extracellular enzyme activities

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Journal of Environmental Sciences 2019年第2期31卷 249-258页

作者： Zdeněk Ko?ná? Tereza ?ástková Lucie Wiesnerová Luká? Praus Ivan Jablonsky Martin Koudela pavel Tlusto? Department of Agroenvironmental Chemistry and Plant nutrition Faculty of AgrobiologyFood and Natural ResourcesCzech University of Life Sciences Prague Department of Horticulture Faculty of AgrobiologyFood and Natural ResourcesCzech University of Life Sciences Prague

A 120-day experiment was conducted to compare the removal of polycyclic aromatic hydrocarbons(PAHs) from agricultural soil after natural attenuation(nA), phytoremediation(P), mycoremediation(M), and plant-assisted mycoremediation(PAM) approaches in relation to the extracellular enzyme activities in soil. The nA treatment removed the total soil PAH content negligibly. The P treatment using maize(Zea mays) enhanced only the removal of low and medium molecular PAHs. The Pleurotus ostreatus cultivated on 30–50 mm wood chip substrate used in M treatment was the most successful in the removal of majority PAHs. Therefore,significantly(p nts was observed. When using the same fungal substrate together with maize in PAM treatment, the total PAH removal was not statistically different from the previous M treatment. However, the maize-assisted mycoremediation treatment significantly boosted fungal biomass, microbial and manganese peroxidase activity in soil which strongly correlated with the removal of total PAHs. The higher PAH removal in that PAM treatment could be reflected in the following post-harvest time. Our suggested M and PAM approaches could be promising in situ bioremediation strategies for PAH-contaminated soils.

关键词： PAHs Biodegradation White-rot fungi Ligninolytic enzymes Microbial activity

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

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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 Global 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 submountain *** remote sensing of mountain forests enables 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 between various spatial resolutions during environmental *** evaluation was divided into managed and natural forests in the Hruby Jeseník Mts.(Czech Republic;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)by MODIS VI during alternating drought and flood periods *** local environmental influence was assessed using the discrimination function(DF)separability of forest damage in the training *** regional influence was assessed through map algebra estimated via the DF and a forest decline spatial model based on EPs from differences between risk growth conditions and biomass 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 biomass 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 by 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 both management and risk predispositions.

关键词： Mountain environment Forest damage types Canopy density Soil group norway spruce(Picea abies)

Advanced machine learning decision policies for diameter control of carbon nanotubes

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npj Computational Materials 2021年第1期7卷 1454-1462页

作者： Rahul Rao Jennifer Carpena-núñez pavel nikolaev Michael A.Susner Kristofer G.Reyes Benji Maruyama Materials and Manufacturing Directorate Air Force Research LaboratoryWPAFBDaytonOH 45433USA UES Inc.DaytonOH 45423USA Department of Materials Design and Innovation University at BuffaloBuffaloNY 14260USA

The diameters of single-walled carbon nanotubes(SWCnTs)are directly related to their electronic properties,making diameter control highly desirable for a number of *** we utilized a machine learning planner based on the Expected Improvement decision policy that mapped regions where growth was feasible *** feasible and further optimized synthesis conditions to selectively grow SWCnTs within a narrow diameter *** maximized two ranges corresponding to Raman radial breathing mode frequencies around 265 and 225 cm^(−1)(SWCnT diameters around 0.92 and 1.06 nm,respectively),and our planner found optimal synthesis conditions within a hundred *** post-growth characterization showed high selectivity in the optimized growth experiments compared to the unoptimized growth ***,our planner revealed significantly different synthesis conditions for maximizing the two diameter ranges in spite of their relative *** study shows the promise for machine learning-driven diameter optimization and paves the way towards chirality-controlled SWCnT growth.

关键词： synthesis carbon diameters