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Influence of Internal Channel Geometry of Gas Turbine Blade on Flow Structure and Heat Transfer

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Journal of Thermal Science 2017年第6期26卷 514-522页

作者： Ryszard Szwaba piotr kaczynski Janusz Telega piotr Doerffer Institute of Fluid-Flow Machinery Polish Academy of Sciences (IMP PAN) Fiszera 14 80-952 Gdansk POLAND

This paper presents the study of the influence of channel geometry on the flow structure and heat transfer, and also their correlations on all the walls of a radial cooling passage model of a gas turbine blade. The investigations focus on the heat transfer and aerodynamic measurements in the channel, which is an accurate representation of the configuration used in aeroengines. Correlations for the heat transfer coefficient and the pressure drop used in the design of internal cooling passages are often developed from simplified models. It is important to note that real engine passages do not have perfect rectangular cross sections, but include a corner fillets, ribs with fillet radii and a special orientation. Therefore, this work provides detailed fluid flow and heat transfer data for a model of radial cooling geometry which has very realistic features.

关键词：流动结构几何形状燃气轮机叶片传热流道发动机结构通道模型冷却通道

Flow Structure and Heat Exchange Analysis in Internal Cooling Channel of Gas Turbine Blade

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Journal of Thermal Science 2016年第4期25卷 336-341页

作者： Ryszard Szwaba piotr kaczynski piotr Doerffer Janusz Telega Institute of Fluid-Flow Machinery Polish Academy of Sciences(IMP PAN)

This paper presents the study of the flow structure and heat transfer,and also their correlations on the four walls of a radial cooling passage model of a gas turbine *** investigations focus on heat transfer and aerodynamic measurements in the channel,which is an accurate representation of the configuration used in *** for the heat transfer coefficient and the pressure drop used in the design of radial cooling passages are often developed from simplified *** is important to note that real engine passages do not have perfect rectangular cross sections,but include coiner fillet,ribs with fillet radii and special ***,this work provides detailed fluid flow and heat transfer data for a model of radial cooling geometry which possesses very realistic features.

关键词：冷却通道流动结构燃气轮机叶片换热分析发动机结构传热特性通道模型圆角半径

Laminar-Turbulent Transition Tripped by Step on Transonic Compressor Profile

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Journal of Thermal Science 2018年第1期27卷 1-7页

作者： Pawel Flaszynski piotr Doerffer Ryszard Szwaba Michal piotrowicz piotr kaczynski The Szewalski Institute of Fluid-Flow Machinery Polish Academy of Sciences(IMP PAN) Fiszera 14GdanskPoland

The shock wave boundary layer interaction on the suction side of transonic compressor blade is one of the main objectives of TFAST project(Transition Location Effect on Shock Wave Boundary Layer Interaction). The experimental and numerical results for the flow structure investigations are shown for the flow conditions as the existing ones on the suction side of the compressor profile. The two cases are investigated: without and with boundary layer tripping device. In the first case, boundary layer is laminar up to the shock wave, while in the second case the boundary layer is tripped by the step. Numerical results carried out by means of Fine/Turbo Numeca with Explicit Algebraic Reynolds Stress Model including transition modeling are compared with schlieren, Temperature Sensitive Paint and wake measurements. Boundary layer transition location is detected by Temperature Sensitive Paint.

关键词：压缩机侧面音速相互作用流动条件温度敏感边界层冲击波

Shock Wave Boundary Layer Interaction on Suction Side of Compressor Profile in Single Passage Test Section

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Journal of Thermal Science 2015年第6期24卷 510-515页

作者： Pawel Flaszynski piotr Doerffer Ryszard Szwaba piotr kaczynski Michal piotrowicz The Szewalski Institute of Fluid-Flow Machinery Polish Academy of Sciences (IMP PAN)

The shock wave boundary layer interaction on the suction side of transonic compressor blade is one of the main objectives of TFAST project(Transition Location Effect on Shock Wave Boundary Layer Interaction).In order to investigate the flow structure on the suction side of a profile,a design of a generic test section in linear transonic wind tunnel was *** experimental and numerical results for the flow structure investigations are shown for the flow conditions as the existing ones on the suction side of the compressor *** the sidewalls the suction slots are applied for the corner flow structure *** allows to control the Axial Velocity Density Ratio(AVDR),important parameter for compressor cascade *** results for Explicit Algebraic Reynolds Stress Model with transition modeling are compared with oil flow visualization,schlieren and Pressure Sensitive *** layer transition location is detected by Temperature Sensitive Paint.

关键词：边界层转捩压气机叶片相互作用激波试验段单通道跨音速风洞外形

Anthropogenic noise interacts with the predation risk assessment in a free-ranging bird

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Current Zoology 2024年第3期70卷 277-283页

作者： piotr Matyjasiak Patrycja Chacińska and piotr Książka Institute of Biological Sciences Cardinal Stefan Wyszyński University in WarsawWóycickiego 1/3PL-01-815 WarsawPoland Department of Environmental Acoustics Institute of Environmental Protection—National Research InstituteKolektorska 4PL-01-692 WarsawPoland

Anthropogenic noise can affect a number of behavioral,physiological,and ecological aspects of animals from major taxonomic groups,raising serious conservation *** example,noise pollution impacts communicative behavior and perception of signals,movements and distribution,as well as predator–prey interactions,such as hunting success or predator detection and predation risk *** have carried out an experimental playback study,in which we investigated whether exposure to anthropogenic noise(sound of a tractor)distracts free-ranging barn swallows Hirundo rustica from paying attention to an approaching human“predator”(the“cognitive distraction”hypothesis),or whether noise leads to increased responsiveness to this“predator”(the“increased threat”hypothesis).The subjects were male barn swallows attending their breeding territories during the time when the females were *** found that barn swallow males initiated fight at signifcantly greater distances to the approaching human“predator”in the noise treatment than during the quiet control *** results suggest that anthropogenic noise causes increased vigilance and reactivity rather than a distraction,enabling birds to avoid the“predator”more *** further discuss the mechanism behind the increased alertness in response to noise and contrast the“increased threat”mechanism,usually tested in previous studies,with an alternative“cognitive sensitization”mechanism.

关键词： anthropogenic noise barn Swallow cognitive distraction flight initiation distance Hirundo rustica predation risk assessment

Effects of small molecules on neurogenesis:Neuronal proliferation and differentiation

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Acta Pharmaceutica Sinica B 2024年第1期14卷 20-37页

作者： MichałK Jastrze˛bski piotr Wo´jcik piotr Ste˛pnicki Agnieszka A.Kaczor Department of Synthesis and Chemical Technology of Pharmaceutical Substances with Computer Modeling Laboratory Medical University of LublinFaculty of PharmacyLublin PL-20093Poland School of Pharmacy University of Eastern FinlandKuopio FI-70211Finland

Neurons are believed to be non-proliferating ***,neuronal stem cells are still present in certain areas of the adult brain,although their proliferation diminishes with *** as with other cells,their proliferation and differentiation are modulated by various *** mechanisms are foundational to the strategies developed to induce neuronal proliferation and differentiation,with potential therapeutic applications for neurodegenerative *** most common among these diseases are Parkinson's disease and Alzheimer's disease,associated with the formation ofβ-amyloid(Aβ)aggregates which cause a reduction in the number of *** such as LiCl,4-aminothiazoles,Pregnenolone,ACEA,harmine,D2AAK1,methyl 3,4-dihydroxybenzoate,and shikonin may induce neuronal proliferation/differentiation through the activation of pathways:MAPK ERK,PI3K/AKT,NFκB,Wnt,BDNF,and ***,combinations of these compounds can potentially transform somatic cells into *** transformation process involves the activation of neuron-specific transcription factors such as NEUROD1,NGN2,ASCL1,and SOX2,which subsequently leads to the transcription of downstream genes,culminating in the transformation of somatic cells into *** diseases are not the only conditions where inducing neuronal proliferation could be ***,the impact of pro-proliferative compounds on neurons has also been researched in mouse models of Alzheimer's disease.

关键词： Neurogenesis Proliferation Differentiation Maturation Small-molecules Drug coctail Alzheimer’s disease Parkinson’s disease

Odd-even effects in the structure and properties of aryl-substituted aliphatic self-assembled monolayers

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Nano Research 2024年第5期17卷 4231-4243页

作者： piotr Cyganik Andreas Terfort Michael Zharnikov Jagiellonian University Faculty of PhysicsAstronomy and Applied Computer ScienceSmoluchowski Institute of PhysicsŁojasiewicza 1130-348 KrakówPoland Institut für Anorganische und Analytische Chemie Universität FrankfurtMax-von-Laue-Straße 760438 FrankfurtGermany Applied Physical Chemistry Heidelberg UniversityIm Neuenheimer Feld 25369120 HeidelbergGermany

Self-assembled monolayers(SAMs)represent an important tool in context of nanofabrication and molecular engineering of surfaces and *** properties of functional SAMs depend not only on the character of the tail groups at the SAM-ambient interface,but are also largely defined by their *** its turn,the latter parameter results from a complex interplay of the structural forces and a variety of other factors,including so called odd-even effects,*** of the SAM structure and properties on the parity of the number(odd or even)of individual building blocks in the backbone of the SAM *** most impressive manifestation of the odd-even effects is the structure of aryl-substituted alkanethiolate SAMs on Au(111)and Ag(111),in which,in spite of the fact that the intermolecular interaction is mostly determined by the aryl part of the monolayers,one observes a pronounced dependence of molecular inclination and,consequently,the packing density of the SAM-forming molecules on the parity of number of methylene units in the alkyl *** we review the properties of the above systems as well as address fundamental reasons behind the odd-even effects,including the existence of a so-called bending potential,which is frequently disregarded in analysis of the structure-building *** generality of the odd-even effects in SAMs is additionally supported by the recent data for SAMs on GaAs,scanning tunneling microscopy data for SAMs on Ag(111),and the data for the monolayers with selenolate and carboxyl anchoring groups on Au(111)and Ag(111).The implications of these effects in terms of the control over the packing density and orientation of the tail groups at the SAM-ambient interface,structural perfection,polymorphism,temperature-driven phase transitions,and SAM stability toward such factors as ionizing radiation,exchange reaction,and electrochemical desorption are *** implications place the odd-even effects as an important tool

关键词： self-assembled monolayers molecular films surface and interface engineering odd-even-effects

Low heritability of social phenotypes in a nonpasserine waterbird

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Current Zoology 2024年第4期70卷 465-471页

作者： piotr Minias Joanna Drzewińnska-Chanko Radostaw Wtodarczyk Departmentof Biodiversity Studies and Bioeducation Faculty of Biology and Environmental ProtectionUniversity oftodzBanacha 1/390-237 todzPoland

Most behavioral traits are known to be weakly heritable,possibly due to their extreme complexity and *** this general pattern,within-species variation in avian colony size choice has been reported to have a strong additive genetic component,but we are aware of no attempts to assess the heritability of avian sociality at the finer spatial ***,we used an animal model and parent-offspring regression to quantify additive genetic variance in social phenotype(local nesting density)in a nonpasserine waterbird,the common tern Sterna *** this purpose,we used a novel experimental framework,where variation in the social environment was generated by providing birds with artificial patches of attractive nesting substrate that markedly varied in *** 2011-2019,we collected data on social preferences for either low or high nesting density in over 250 individuals,either kin(mostly parent-offspring relationships)or non-kin recorded breeding multiple times across *** heritability estimates of local nesting density were low(<0.10),irrespectively of fixed effects(sex and year)included in the models,data used in the modeling(all individuals *** recruits),or methodological approach(animal model ***-offspring regression).We conclude that avian sociality,as measured at the local scale,may be much less heritable than colony size choice,as measured at the landscape *** study adds to the understanding of additive genetic variance in avian behavior,and it underlines a scale dependency in the heritability of behavioral traits.

关键词： animal model birds common tern heritability parent-offspring regression sociality.

Early response of understory vegetation to the mass dieback of Norway spruce in the European lowland temperate forest

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Forest Ecosystems 2024年第2期11卷 214-225页

作者： Jan Marek Matuszkiewicz Andrzej N.Affek piotr Zaniewski Ewa Kołaczkowska Faculty of Geography and Regional Studies University of WarsawPoland Institute of Geography and Spatial Organization Polish Academy of SciencesPoland Institute of Forest Sciences Warsaw University of Life SciencesPoland

Spruce-dominated forests are commonly exposed to disturbances associated with mass occurrences of bark *** dieback of trees triggers many physical and chemical processes in the ecosystem resulting in rapid changes in the vegetation of the lower forest *** aimed to determine the response of non-tree understory vegetation to the mass dieback of Norway spruce(Picea abies)in the first years after the disturbance caused by the European spruce bark beetle(Ips typographus)*** study area was the Białowieża Biosphere Reserve covering the Polish part of the emblematic Białowieża Forest,in total 597km^(2).The main data source comprised 3,900 phytosociological relevés(combined spring and summer campaigns)collected from 1,300 systematically distributed forest sites in 2016–2018–the peak years of the bark beetle *** found that the understory responded immediately to mass spruce dieback,with the most pronounced changes observed in the year of the disturbance and the subsequent ***-tolerant forest species declined in the initial years following the mass spruce dieback,while hemicryptophytes,therophytes,light-demanding species associated with non-forest seminatural communities,as well as water-demanding forest species,*** acetosella,the most common understory species in the Białowieża Forest,showed a distinct fluctuation pattern,with strong short-term expansion right after spruce dieback,followed by a gradual decline over the next 3–4 years to a cover level 5 percentage points lower than before the ***,our study revealed that mass spruce dieback selectively affects individual herb species,and their responses can be directional and non-directional(fluctuation).Furthermore,we demonstrated that the mass dieback of spruce temporarily increases plant species diversity(α-diversity).

关键词： Forest disturbance Bark beetle outbreak Picea abies Ips typographus Response of understory vegetation Herbaceous species Biaowieza Forest