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Experimental investigation of radiative heat propagation in a simplified generic packed bed

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particuology 2024年第5期88卷 149-160页

作者： Matthias Tyslik Lukas pörtner Siegmar Wirtz martin Schiemann Institute of Energy plant Technology Ruhr-University Bochum44780 BochumGermany

A novel test rig for the investigation of radiative heat transfer in packed beds has been developed and is introduced with representative experimental *** individual components and the calibration are *** generic packed bed is realized in a simplified way by an arrangement of parallel rods,which represent particles in *** this arrangement,electrically heated rods provide the radiation propagating through the rod array to heat the passive counterparts.A sophisticated temperature-control scheme with a large number of thermocouples and infrared-imaging provides in-depth information about heat transfer in the *** radiation intensities are determined with a Fourier-transform infrared spectroscopy,which has been modified and validated for this specific *** order to compare the influence of different surface properties of particles on the heat propagation and surface reflections,rod samples made of stainless steel and magnesium oxide are *** influence of material properties becomes clearly visible by comparing the high radiation intensities resulting from a stainless steel rod array to the same geometry built from magnesium oxide *** addition,the influence of the surface properties is particularly evident in the infrared images since the reflections are significantly higher for the stainless steel samples than for the magnesium oxide *** experimental results in the current work demonstrate the ability of the test rig to provide data with a well-defined accuracy as a validation base for numerical radiation simulations in packed beds.

关键词： Thermal radiation Spectral reflections Fourier-transform infrared spectroscopy

Immune consequences of exercise in hypoxia:A narrative review

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Journal of Sport and Health Science 2024年第3期13卷 297-310,I0002页

作者： Johannes Burtscher Qadar pasha Neha Chanana Gregoire p.Millet martin Burtscher Barbara Strasser Institute of Sport Sciences University of LausanneLausanne 1015Switzerland Institute of Hypoxia Research New Delhi 110067India Department of Biochemistry Jamia HamdardNew Delhi 110062India Department of Sport Science University of InnsbruckInnsbruck 6020Austria Faculty of Medicine Sigmund Freud Private UniversityVienna 1020Austria Ludwig Boltzmann Institute for Rehabilitation Research Vienna 1100Austria

Immune outcomes are key mediators of many health benefits of exercise and are determined by exercise type,dose(frequency/duration,intensity),and individual ***,reduced availability of ambient oxygen(hypoxia)modulates immune functions depending on the hypoxic dose and the individual capacity to respond to *** combined exercise and hypoxia(e.g.,high-altitude training)sculpts immune responses is not well understood,although such combinations are becoming increasingly ***,in this paper,we summarize the impact on immune responses of exercise and of hypoxia,both independently and together,with a focus on specialized cells in the innate and adaptive immune *** review the regulation of the immune system by tissue oxygen levels and the overlapping and distinct immune responses related to exercise and hypoxia,then we discuss how they may be modulated by nutritional ***,antioxidant,and anti-inflammatory mechanisms underlie many of the adaptations that can lead to improved cellular metabolism,resilience,and overall immune functions by regulating the survival,differentiation,activation,and migration of immune *** review shows that exercise and hypoxia can impair or complement/synergize with each other while regulating immune system *** acclimatization,training,and nutritional strategies can be used to avoid risks and tap into the synergistic potentials of the poorly studied immune consequences of exercising in a hypoxic state.

关键词： Altitude Exercise Hypoxia Immune response Training

Carbon dioxide enrichment affected flower numbers transiently and increased successful post-pollination development stably but without altering final acorn production in mature pedunculate oak (Quercus robur L.)

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Journal of Forestry Research 2024年第4期35卷 1-12页

作者： Ryan McClory richard H.Ellis martin Lukac Jo Clark Carolina Mayoral Kris M.Hart Andrew R.G.plackett A.Rob MacKenzie School of Agriculture Policy and DevelopmentUniversity of ReadingAgricultureEarley GateWhiteknights RoadPO Box 237Reading RG66EUUK Faculty of Forestry and Wood Sciences Czech University of Life Sciences PraguePrague 165000Czechia Future Trees Trust Harwell Innovation CentreBuilding 173Curie AvenueHarwellOxford OX110QGUK Birmingham Institute of Forest Research University of BirminghamEdgbastonBirmingham B152TTUK School of Biosciences University of BirminghamEdgbastonBirmingham B152TTUK School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirmingham B152TTUK

Acorn production in oak(Quercus spp.)shows considerable inter-annual variation,known as masting,which provides a natural defence against seed predators but a highly-variable supply of acorns for uses such as in commercial tree planting each *** emissions of greenhouse gases have been very widely reported to influence plant growth and seed or fruit size and quantity via the‘fertilisation effect’that leads to enhanced *** examine if acorn production in mature woodland communities will be affected by further increase in CO_(2),the contents of litter traps from a Free Air Carbon Enrichment(FACE)experiment in deciduous woodland in central England were analysed for numbers of flowers and acorns of pedunculate oak(Quercus robur L.)at different stages of development and their predation levels under ambient and elevated CO_(2) ***-annual variation in acorn numbers was considerable and cyclical between 2015 and 2021,with the greatest numbers of mature acorns in 2015,2017 and 2020 but almost none in *** numbers of flowers,enlarged cups,immature acorns,empty acorn cups,and galls in the litter traps also varied amongst years;comparatively high numbers of enlarged cups were recorded in 2018,suggesting *** at this site is a fruit maturation masting species(i.e.,the extent of abortion of pollinated flowers during acorn development affects mature acorn numbers greatly).Raising the atmospheric CO_(2) concentration by 150μL L^(−1),from early 2017,increased the numbers of immature acorns,and all acorn evidence(empty cups+immature acorns+mature acorns)detected in the litter traps compared to ambient controls by 2021,but did not consistently affect the numbers of flowers,enlarged cups,empty cups,or mature *** number of flowers in the elevated CO_(2) plots’litter traps was greater in 2018 than 2017,one year after CO_(2) enrichment began,whereas numbers declined in ambient *** with CO_(2) also increased the number o

关键词： Quercus robur L. Acorns Masting pedunculate oak Carbon dioxide

Kentish plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) prefer shells for nesting:A field experiment

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Avian Research 2024年第1期15卷 55-59页

作者： Macarena Castro Andrés De la Cruz Nuria martin-Sanjuan Alejandro pérez-Hurtado Instituto Universitario de Investigacion Marina(INMAR) Campus de Excelencia Internacional del Mar(CEIMAR)Departamento de BiologíaUniversidad de CadizPuerto RealSpain Servicios centrales de Investigacion Salinas de la Esperanza Universidad de CadizPuerto RealSpain

Shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal ***,supratidal habitats as saltpans could play a role in buffering human *** have shown to be important as feeding or breeding sites of some shorebird species.A potential conservation strategy to increase shorebird populations in saltpans is to manipulate the cues that birds use to select optimal breeding *** it is hypothesized that shorebirds are attracted to bivalve shells due to the advantages they *** this hypothesis,we supplemented a restored saltpan in 2019 and 2021 with bivalve shells,expecting an increase in the number of breeding birds’ *** than 75% of Kentish plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) nests were found in patches with shells in both *** best model for both species indicates that the presence of shells is the factor that most correlates with the location of *** probability of choosing one place over another to settle their nest increases in areas with an abundance of shells,double in the case of the Kentish plover and triple in the case of the Little *** result of this study may constitute a valuable tool for attracting birds to restored saltpans and could contribute to the success of expensive restoration projects where time is usually a constraint.

关键词： Habitat management Nest site selection Saltpan restoration Shell supplementation Shorebirds

Comprehensive Euler/Lagrange modelling including particle erosion for confined gas-solid flows

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particuology 2024年第1期84卷 209-235页

作者： Guiherme A.Novelletto Ricardo martin Sommerfeld Multiphase Flow Systems Institute of Process EngineeringOtto-von-Guericke-University MagdeburgHoher Weg 7b06120Halle(Saale)Germany

The present research aims to assess the capability of a comprehensive Euler/Lagrange approach for predicting gas-solid flows and the associated solid particle *** open-source code OpenFOAM®4.1 was used to carry out the numerical simulations,where the standard Lagrangian libraries were substantially extended to account for all necessary *** are tracked considering both translational and rotational motion as well as all relevant forces,such as gravity/buoyancy,drag and transverse lift due to shear and particle *** tracking time step was dynamically adapted ac-cording to the locally relevant time scales,which drastically reduces computational *** approaches are adopted to model particle turbulent dispersion,particle collisions with rough walls and particle-particle *** solid particle erosion models,available in the literature,were considered to estimate pipe bend *** study cases are provided to validate the adopted nu-merical approach and erosion models *** first case intends to evaluate the ability of the extended CFD code to predict the behaviour of gas-solid flows in pneumatic conveying *** goal is achieved by comparing the numerical results with the experimental data obtained by Huber(1997)and Huber and Sommerfeld(1994,1998)in a pneumatic conveying ***,the importance of considering inter-particle collisions and surface roughness for predicting particle velocity,mass flux and mean diameter distributions in gas-solid flows is *** second and third case intend to evaluate the ability of the erosion models in estimating bend erosion in diluted gas-solid *** erosion data obtained experimentally by Mazumder et al.(2008)and Solnordal et al.(2015)in very dilut pneumatic conveying systems is used for validating the numerical results,neglecting now inter-particle collisions and two-way *** a comprehensive analysis of the different influential properti

关键词： pneumatic conveying pipe bend Numerical calculation(CFD) Euler/Lagrange approach Erosion models Wall roughness

Differential roles of seed and sprout regeneration in forest diversity and productivity after disturbance

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Forest Ecosystems 2024年第3期11卷 371-380页

作者： Marek Mejstrík martin Svatek martina pollastrini martin Sramek Radim Matula Department of Forest Ecology Faculty of Forestry and Wood SciencesCzech University of Life Sciences PragueKamýcka 12916500PragueCzech Republic Department of Forest Botany Dendrology and GeobiocoenologyFaculty of Forestry and Wood TechnologyMendel University in BrnoZemedelska 361300BrnoCzech Republic Department of Agriculture FoodEnvironment and ForestryUniversity of FirenzePiazzale Delle Cascine 2850144FirenzeItaly

Natural regeneration after disturbances is a key phase of forest development,which determines the trajectory of successional changes in tree species composition and *** trees can originate from either seeds or sprouts produced by disturbed trees with sprouting *** both regeneration strategies often develop and co-occur after a disturbance,they tend to affect forest development differently due to significant functional ***,the origin of tree regeneration is rarely distinguished in post-disturbance forest surveys and ecological studies,and the differential roles of seed and sprout regeneration in forest productivity and diversity remain poorly *** address these research gaps,we explored the role of sprout and seed regeneration in the formation of woody species diversity and above-ground biomass(AGB)productivity in early-stage forest *** were collected in two experimental forest stands in the Czech Republic,where trees were cut with varying intensities with the density of residual(uncut)trees ranging from 0 to 275 trees per *** trees were mapped and their sizes were measured before cutting and then,either as a stump with sprouts or a residual tree,remeasured 11 years *** addition,all tree saplings were mapped and measured 11 years after logging,and their origin(sprout or seed)was *** assess abundances and productivity,we estimated AGB of all2,685 sprouting stumps of 19 woody species and 504 generative(i.e.,seed origin)individuals of 16 woody species,using allometric ***-effects models were used to analyze the effects of each regeneration strategy on woody species diversity and the total AGB under varying densities of residual *** multidimensional scaling was used to evaluate the effect of regeneration strategies on species *** and diversity of sprouts were significantly higher than those of seed *** formed on average97.1%of

关键词： Resprouting Seeding Residual trees Tree diversity Above-ground biomass

Applicability limits of the DAX test in plastic bonded explosives

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Defence Technology（防务技术） 2024年第6期36卷 64-70页

作者： martin Künzel Jindrich Kucera Jiri pachman OZM Research Bliznovice 32Hrochuv Tynec 53862Czech Republic Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceStudentska 95Pardubice 53210Czech Republic

The Disc Acceleration e Xperiment(DAX)is one of the most recent experimental methods of performance characterization of new energetic materials.A cylindrical explosive charge accelerates a thin metallic disc and its velocity is measured continuously using photonic Doppler *** detonation velocity is measured *** DAX test can be used to obtain the Chapman-Jouguet(CJ)detonation pressure and to describe detonation products expansion using reduced amount of explosive.A series of DAX tests was performed at various charge diameters and disc thicknesses with Semtex 1 A plastic bonded explosive and sensitized *** DAX-like evaluation was also applied to previously measured data of Semtex 1A and A-IX-1 *** optimum disc thickness is determined by the disc to explosive mass ratio of *** repeatability of the Semtex 1 A detonation pressure results is about four times lower compared to the pressed and liquid explosives.

关键词： Flyer plate Detonation pressure photonic Doppler velocimetry Semtex

Are TrkB receptor agonists the right tool to fulfill the promises for a therapeutic value of the brain-derived neurotrophic factor?

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Neural Regeneration Research 2024年第1期19卷 29-34页

作者： Marta Zagrebelsky martin Korte Division of Cellular Neurobiology Zoological InstituteTU BraunschweigBraunschweigGermany Helmholtz Centre for Infection Research AG NINDBraunschweigGermany

Brain-derived neurotrophic factor signaling via its receptor tro pomyosin receptor kinase B regulates several crucial physiological *** has been shown to act in the brain,promoting neuronal survival,growth,and plasticity as well as in the rest of the body where it is involved in regulating for instance aspects of the *** to its crucial and very pleiotro pic activity,reduction of brain-derived neurotrophic factor levels and alterations in the brain-derived neurotrophic factor/tropomyosin receptor kinase B signaling have been found to be associated with a wide spectrum of neurological *** r,because of its poor bioavailability and pharmacological properties,brain-derived neurotrophic factor itself has a very low therapeutic ***,the concomitant binding of exogenous brain-derived neurotrophic factor to the p75 neurotrophin receptor has the potential to elicit several unwanted and deleterious side *** re,developing tools and approaches to specifically promote tropomyosin receptor kinase B signaling has become an important goal of translational *** the newly developed tools are different categories of tropomyosin receptor kinase B receptor agonist *** this review,we give a comprehensive description of the diffe rent tro pomyosin receptor kinase B receptor agonist drugs developed so far and of the res ults of their application in animal models of several neurological ***,we discuss the main benefits of tropomyosin receptor kinase B receptor agonists,concentrating especially on the new tropomyosin receptor kinase B agonist *** benefits observed both in vitro and in vivo upon application of tropomyosin receptor kinase B receptor agonist drugs seem to predominantly depend on their general neuroprotective activity and their ability to promote neuronal ***,tro pomyosin receptor kinase B agonist antibodies have been shown to specifically bind the tropomyosin recepto

关键词： Alzheimer's disease brain-derived neurotrophic factor depression parkinson's disease tropomyosin receptor kinase B receptor

Optimization of product characteristics of porous carbon agglomerates using a design of experiments in fluidized bed agglomeration

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particuology 2024年第6期89卷 258-269页

作者： martin Oelofse Robert Rack Marcelle Hilden peter Langguth Department of pharmaceutical Technology and Biopharmaceutics Johannes Gutenberg UniversityMainzGermany Carbon Advanced Solutions GmbH HeuchelheimGermany

Spraying parameters during particle agglomeration processes can affect the agglomeration kinetics and particle *** study was conducted to better understand the influence of the spraying parameters in a fluidized bed wet agglomeration process,and the influence on the stability characteristics of carbon tablets.A formulation based on fine carbon and peroxide powder,as well as carboxymethyl cellulose as a binder,was used to produce agglomerates in a first production *** in a second production step carbon tablets with a high porosity were molded for the customer goods *** optimization of the compressive strength of these carbon tablets was the goal of the *** agglomerates were produced with a laboratory scale granulator called“proCell”and were compressed with a five-cavity mechanical *** screening of the agglomeration process parameters and their influence on the agglomerates quality,as well as the performance characteristics of the carbon tablets,were investigated using a multilevel factorial *** experimental runs were done by varying atomized air pressure and feed rate of the *** was determined by the design *** findings of the statistical trials showed that low atomized air pressure and a low feed rate lead to a higher tablet compressive strength.

关键词： Wet agglomeration Fluidized bed Design of experiments Carbon agglomerates and tablets