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Specialist predator in a multi-species prey community:boreal voles and weasels

Integrative Zoology 2008年第1期3卷 51-63页

作者： Janne SUNDELL Hannu YLÖnen Metapopulation Research Group Department of Biological and Environmental SciencesUniversity of HelsinkiHelsinkiFinland Konnevesi Research Station Department of Biological and Environmental ScienceUniversity of JyväskyläJyväskyläFinland

Dissimilar vulnerabilities of different prey types and preferences of predators are factors likely to contribute to community *** may happen via differential individual properties of prey animals(***,escape)or via habitat effects making hunting by a predator easier and more rewarding in some habitats,or ***,community dynamics may be influenced by predator mediated apparent competition,in which an increase in one prey type has negative effects on another prey type indirectly via the shared *** summarize the current knowledge from the field in a model predator–prey system consisting of sympatric boreal vole species and their common specialist predator and review field studies using predator manipulation and studies on the responses of individuals in the laboratory and in outdoor *** vole species studied represent different prey types that are thought to have different *** observations on the main resident specialist predator,the least weasel(Mustela nivalis nivalis L.),show that it hunts according to prey availability and suitability of the hunting *** voles respond to the presence of the predator behaviorally in various ways to avoid *** conclude that even if the least weasel is a specialized predator of small rodents it acts like a generalist predator within the small rodent guild and may facilitate the coexistence of prey species via predator *** may lead to interspecific synchrony between prey populations,which has often been *** suggest that the processes determining the community impact of predator–prey interactions are driven by the behavioral arms race between the predator and the prey,together with the habitat-dependent density of prey and net gain for the predator.

关键词： apparent competition predator–prey interaction prey choice vole cycle

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Mean-field stochastic differential equations with a discontinuous diffusion coefficient

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Probability, Uncertainty and Quantitative Risk 2023年第3期8卷 351-372页

作者： Jani Nykänen Department of Mathematics and Statistics University of JyväskyläP.O.Box 35FI-40014Finland

We study R^(d)-valued mean-field stochastic differential equations with a diffusion coefficient that varies in a discontinuous manner on the L_(p)-norm of the *** establish the existence of a unique global strong solution in the presence of a robust drift,while also investigating scenarios where the presence of a global solution is not assured.

关键词： Mean-field stochastic differential equation Discontinuous diffusion coefficient Existence and nonexistence of strong solutions in L_(p)

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Recent Advances in Catalytic Carbonylation Reactions in Alternative Reaction Media

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Chinese Journal of Chemistry 2024年第4期42卷 406-429页

作者： Csaba Árvai László T.mika Department of Chemical and Environmental Process Engineering Faculty of Chemical Technology and BiotechnologyBudapest University of Technology and EconomicsMűegyetem rkp.3H-1111 BudapestHungary

Since the discovery of the hydroformylation(oxo-synthesis or Roelen reaction)and the Reppe-reaction,the transition metal-catalyzed carbonylation reactions,providing versatile,facile,and even atom-economic methods for the selective incorporation of C=O functionality to various skeletons,have gained tremendous importance in synthetic organic chemistry from laboratories to industrial *** carbonylation of carbon-carbon multiple bonds,aromatic halides,triflates,etc.,in the presence of various nucleophiles has led the way to produce aldehydes,carboxylic acids,esters,amides,etc.,in the fine chemical ***,these protocols usually proceed in conventional,fossil-based,and usually toxic reaction ***,several attempts have been directed to developing efficient carbonylation methods in alternative,less harmful,non-fossil-based and even in renewable reaction *** this review,we overview the recent applications of alternative solvents such as water,biomass-based alcohols,γ-valerolactone(GVL),2-methyltetrahydrofuran(2-MeTHF),ionic liquids(ILs),deep eutectic solvents(DES),alkyl levulinates,limonene,α-pinene,and dimethyl carbonate as well as fluorous media to improve efficiency,safety and environmentally benign nature of carbonylation protocols.

关键词： Carbonylation Catalysis Solvents Green chemistry Carbon monoxide Transition metals Homogeneous catalysis Palladium

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Gadolinium doped tin dioxide nanoparticles: an efficient visible light active photocatalyst

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Journal of Rare Earths 2015年第12期33卷 1275-1283页

作者： Abdullah M Al-Hamdi mika Sillanp?? Joydeep Dutta Laboratory of Green Chemistry Lappeenranta University of Technology Chair in Nanotechnology Water Research Center Sultan Qaboos University Functional Materials Division School of Information and Communication Technology KTH Royal Institute of Technology

Photocatalytic degradation of phenol with sol-gel prepared rare earth doped tin dioxide （SnO2） nanoparticles was reported. Gadolinium doped tin dioxide （SnO2：Gd） nanoparticles were found to absorb higher visible light compared to lanthanum, neodymium and cerium doped materials that were studied in detail. Photocatalytic degradation of phenol under artificial white light and sunlight in the presence of SnO2：Gd nanoparticles was studied with high performance liquid chromatography （HPLC）, capillary electrophoresis （CE）, total organic carbon （TOC） measurements and the determination of chemical oxygen demand （COD）. Clear correlations be- tween the results obtained from these multiple measurements were found, and a kinetic pathway for the degradation process was pro- posed. Within 150 min of solar irradiation, the TOC of a 10 ppm phenol solution in water was reduced by 95%-99%, thus demon- strating that SnO2：Gd nanoparticles are efficient visible light photocatalysts.

关键词： rare earth dopants solar irradiation phenol photo-degradation tin dioxide nanoparticles organic by-products

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Synthesis and application of biocompatible nontoxic nanoparticles for reclamation of Ce^3＋ from synthetic wastewater： Toxicity assessment, kinetic, isotherm and thermodynamic study

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Journal of Rare Earths 2018年第9期36卷 994-1006页

作者： Varsha Srivastava Sidra Iftekhar ZhaoWang Indu Babu mika Sillanpaa Laboratory of Green Chemistry School of Engineering Science Lappeenranta University of Technology Sammonkatu 12 FI-50130 Mikkeli Finland Department of Civil and Environmental Engineering Florida International University Miami EL 33174 USA

The aim of present study is to synthesize forsterite nanoparticles（FRST） for the reclamation of cerium ions（Ce3＋） from synthetic *** aim to synthesize FRST nanoparticles is due to its biocompatible and nontoxic *** formation of nanoparticles with average diameter of 58 nm was confirmed by TEM *** images of bare FRST nanoparticles show a heterogeneous surface with porous *** surface area of FRST nanoparticles is calculated to be 33.69 m2/*** significant uptake of Ce3＋ ions can be obtained for all the selected concentrations（25-150 mg/L） within 2 h of adsorbent—adsorbate *** pH study shows that by increasing pH from acidic to alkaline range,higher removal can be *** study demonstrates the endothermic nature of Ce3＋*** value of sticking probability suggests very high sticking probability of Ce3＋ ion for FRST ***3＋ uptake is favored by higher temperature and with the increase in temperature from298 to 328 K,Langmuir adsorption capacity increases from 36.45 to 42.99 m2/*** of FRST nanoparticles was also investigated for other light and heavy rare earth elements in single solute and multisolute systems,FRST nanoparticles show the significant removal of divalent metallic pollutants as *** assessment of chemical toxicity of treated wastewater was carried out with the bioluminescent photobacterium（Vibrio fischeri） and decreased toxicity was observed in treated water *** outcome of present study suggests that the FRST nanoparticles can be efficiently utilized for the removal of Ce3＋ ions and a wide range of other pollutant species as well.

关键词： Forsterite Rare earth elements Isotherm model Cerium Metallic pollutants

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Tackling boundaries of CCS in market deployment of second-generation oxy-fuel technology

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Clean Energy 2018年第1期2卷 72-81页

作者： Kalle Nuortimo Timo Eriksson Reijo Kuivalainen Janne Härkönen Harri Haapasalo Timo Hyppänen Sumitomo SHI FW Energia Oy P.O.Box 201 FI-78201 VarkausFinland Sumitomo SHI FW Energia Oy P.O.Box 7FI-02130 EspooFinland Industrial Engineering and Management University of OuluP.O.Box 4610FI-90014Finland LUT School of Energy Systems PL 2053851 LappeenrantaFinland

This article discusses the market potential estimation results at different stages of second-generation oxy-fuel technology for carbon capture and storage,where oxygen content is increased in order to increase efficiency and product life *** article highlights the challenges to commercializing an energy technology with long development lead *** related to external market environment,regulations and market price for carbon dioxide(CO_(2))also need to be *** study is based on a second-generation oxy-CFB technology evaluation,SWOT analysis and product life-cycle *** commercialization of second-generation oxy-fuel technology,estimated as a basis of oxy-CFB technology,is largely found to be dependent on technical,sociological and economical aspects related to the energy market *** CO_(2) price in European Union(EU)emissions trading is currently below 10€/ton,which does not favour investment in ***_(2) storage also faces public opposition and EU directive *** CO_(2) price needs to be in the range of 30€/ton by 2030,the estimated time of *** development or subsidies would also be required for the second-generation oxy-CFB power production concept to become *** is one of the critical factors in market deployment as the price development is influenced by several external factors,including the EU’s environmental policy,politics and public acceptance.

关键词： Second generation oxyfuel technology market deployment CFB technology tackling boundary of CCS

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Physical activity responsive miRNAs-Potential mediators of training responses in human skeletal muscle?

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Journal of Sport and Health Science 2013年第2期2卷 101-103页

作者： Reeta Kangas Eija Pllnen Gerontology Research Center Department of Health SciencesUniversity of Jyvaskyla

*** basics of miRNA-mediated regulation The plasticity of skeletal muscle is of utmost importance for responding to and coping with environmental demands that emerge from changes in physical activity patterns,nourishment, hormonal status,and *** is well known,a sedentary lifestyle,aging,immobilization,and chronic diseases are associated with reduced muscle mass and function,while regular exercise improves muscle function and reduces the rate of decrement throughout ***,we do not have a complete understanding of the molecular factors controlling skeletal muscle adaptation to exercise *** identified microRNA molecules(miRNAs) have rapidly

关键词： miRNAs 肌肉人体骨骼动响应 microRNA 体力反应训练

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A Configuration Deactivation Algorithm for Boosting Probabilistic Roadmap Planning of Robots

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International Journal of Automation and computing 2012年第2期9卷 155-164页

作者： mika T. Rantanen Martti Juhola Computer Sciences School of Information Sciences University of Tampere

We present a method to improve the execution time used to build the roadmap in probabilistic roadmap planners. Our method intelligently deactivates some of the configurations during the learning phase and allows the planner to concentrate on those configurations that axe most likely going to be useful when building the roadmap. The method can be used with many of the existing sampling algorithms. We ran tests with four simulated robot problems typical in robotics literature. The sampling methods applied were purely random, using Halton numbers, Gaussian distribution, and bridge test technique. In our tests, the deactivation method clearly improved the execution times. Compared with pure random selections, the deactivation method also significantly decreased the size of the roadmap, which is a useful property to simplify roadmap planning tasks.

关键词： Probabilistic roadmaps motion planning collision avoidance sampling algorithms robotics.

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Drying-Mediated Self-Assembly of Graphene for Inkjet Printing of High-Rate Micro-supercapacitors

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Nano-Micro Letters 2020年第3期12卷 155-168页

作者： Szymon Sollami Delekta mika‑Matti Laurila Matti Mantysalo Jiantong Li School of Electrical Engineering and Computer Science KTH Royal Institute of TechnologyElectrum 22916440 KistaSweden Laboratory for Future Electronics Faculty of Information Technology and Communication SciencesTampere University33720 TampereFinland

Scalable fabrication of high-rate micro-supercapacitors(MSCs)is highly desired for on-chip integration of energy storage *** virtue of the special self-assembly behavior of 2D materials during drying thin films of their liquid dispersion,a new inkjet printing technique of passivated graphene micro-flakes is developed to directly print MSCs with 3D networked porous *** presence of macroscale through-thickness pores provides fast ion transport pathways and improves the rate capability of the devices even with solid-state *** multiple-pass printing,the porous microstructure effectively absorbs the successively printed inks,allowing full printing of 3D structured MSCs comprising multiple vertically stacked cycles of current collectors,electrodes,and sold-state *** all-solid-state heterogeneous 3D MSCs exhibit excellent vertical scalability and high areal energy density and power density,evidently outperforming the MSCs fabricated through general printing techniques.

关键词： High-rate micro-supercapacitor 3D micro-supercapacitor Drying-mediated self-assembly Graphene Inkjet printing

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Defect aggregates in the Sr_2MgSi_2O_7 persistent luminescence material

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Journal of Rare Earths 2011年第12期29卷 1130-1136页

作者： Jorma Hls Taneli Laamanen mika Lastusaari Pavel Novák Department of Chemistry University of Turku Turku University Centre for Materials and Surfaces(MatSurf) Graduate School of Materials Research(GSMR) Institute of Physics Academy of Sciences of the Czech Republic

The crystal and electronic structure of the Eu^2＋ doped and defect containing Sr2MgSi2O7 persistent luminescence material were studied using the density functional theory （DFT）. The defects may act as energy storage or even luminescence quenching centres in these materials, however their role is very difficult to confirm experimentally. The probability of vacancy formation was studied using the total energy of the defect containing host. Significant structural modifications in the environment of the isolated defects, especially the strontium vacancy, as well as defect aggregates were found. The experimental band gap energy of Sr2MgSi2O7 was well reproduced by the calculations. The defect induced electron traps close to the host＇s conduction band were found to act as energy storage sites contributing to its efficient persistent luminescence. The interactions between the defects were found to modify both the Eu^2＋ 4f^7 ground state energy as well as the trap structure. The effect of charge compensation induced by the rare earth co-doping on the defect structure and energy storage properties of the persistent luminescence materials was discussed.

关键词： strontium magnesium disilicate vacancy defect aggregate persistent luminescence density functional theory calculations rare earths

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