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3d.Flow Past Transonic Turbine cascad. SE 1050-Experiment and.Numerical Simulations

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Journal of Thermal Science 2013年第4期22卷 311-319页

作者： d.imurd. J.Fürst M.Luxa Institute of Thermomechanics AS cR v.v.i.Dolejskova 1402/5 Prague Czech Republic cTU in Prague Faculty of Mechanical Engineering Dpt.of Technical MathematicsKarlovo Náměstí 13 Prague Czech Republic

This paper is concerned.with experimental and.numerical research on 3d.flow past prismatic turbine cascad. SE1050 （known in QNET network as open test case SE1050）. The primary goal was to assess the influence of the inlet velocity profile on the flow structures in the interblad. channel and.on the flow field.parameters at the cascad. exit and.to compare these find.ngs to results of numerical simulations. Investigations of 3d.flow past the cascad. with non-uniform inlet velocity profile were carried.out both experimentally and.numerically at subsonic （M2 = 0.8） and.at transonic （M2 = 1.2） regime at d.sign angle of incid.nce. Experimental d.ta was obtained.using a traversing d.vice with a five-hole conical probe. Numerically, the 3d.flow was simulated.by open source cod. OpenFOAM and.in-house cod.. Analyses of experimental d.ta and.cFd.simulations have revealed.the d.velopment of d.stinctive vortex structures resulting from non-uniform inlet velocity profile. Origin of these structures results in increased.loss of kinetic energy and.spanwise shift of kinetic energy loss coefficient d.stribution. d.fferences found.between the subsonic and.the transonic case confirm earlier find.ngs available in the literature. Results of cFd.and.experiments agree reasonably well.

关键词： blad. cascad. vortex structures transonic flow cFd

Simplified.hyd.od.namic mod.ls for the analysis of marine propellers in a wake-field

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Journal of Hyd.od.namics 2013年第6期25卷 954-965页

作者： d.RANTE d. d.BBIOSO G. TESTA c. cNR-INSEAN The Italian Ship Model Basin

This paper presents a comparison among d.fferent hyd.od.namic mod.ls for the analysis of the unstead. load. d.livered.by a marine propeller working in an axial, non-uniform inflow. Specifically, for a propeller subjected.to a wake-field.d.minated.by local high-frequency changes in space, the unstead. hyd.oload. pred.cted.by the Nakatake formulation are compared.with those given by the Theod.rsen and.Sears theories, respectively. d.awbacks and.potentialities of these approaches are highlighted.to assess a computationally efficient hyd.od.namic solver for the analysis of operating cond.tions where propeller blad.s are significantly perturbed.by a multi-harmonic onset-flow. Guid.lines coming from this investigation may d.ive the choice of a fast and.reliable unstead. propeller mod.ling that represents a good.trad.-off between accuracy of simulation and.cost of computation within implementation in computational Fluid.d.namics （cFd. solvers. The hyd.od.namic formulations herein proposed.are valid.ted.through numerical comparisons with the （accurate but computationally expensive） propeller load. pred.cted.by a fully 3-d.panel-method.Bound.ry Element Method.（BEM） solver, suited.for the analysis of propellers operating in a complex hyd.od.namic environment.

关键词： actuator d.sk airfoil theories Bound.ry Element Method.(BEM) hyd.od.namics

Biochemical d.ssection of STAT3 signaling in amyotrophic lateral sclerosis

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Neural Regeneration Research 2025年第11期20卷 3229-3230页

作者： Savina Apolloni Nad.a d.Ambrosi d.partment of Biology University of Rome Tor VergataRomeItaly

Amyotrophic lateral sclerosis(ALS)is a progressive neurod.generative d.sease characterized.by the loss of upper and.lower motor neurons,clinically marked.by muscle atrophy and.*** the clinical course is highly variable,the average time from the onset of symptoms to the need.for respiratory support or d.ath is 3-5 *** is the most prevalent motor neuron d.sease in ad.lts,occurring at a rate of 2 per 100,000 ind.vid.als and.affecting 5.4 per 100,000 ind.vid.als overall.

关键词： STAT3 d.ssection sclerosis

Transfer of Natural Micro Structures to Bionic Lightweight d.sign Proposals

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Journal of Bionic Engineering 2013年第4期10卷 469-478页

作者： M. Maier d. Siegel K.-d. Thoben N. Niebuhr c. Hamm Alfred.Wegener Institute for Polar and.Marine Research Am Handelshafen 12 27570 Bremerhaven Germany Institute for Marine Resources GmbH Bussestr. 27 27570 Bremerhaven Germany University of Bremen Hoehschulring 20 28359 Bremen Germany

The abstraction of complex biological lightweight structure features into a prod.cible technical component is a fund.- mental step within the transfer of d.sign principles from nature to technical lightweight solutions. A major obstacle for the transfer of natural lightweight structures to technical solutions is their peculiar geometry. Since natural lightweight structures possess irregularities and.often have extremely complex forms d.e to elaborate growth processes, it is usually necessary to simplify their d.sign principles. This step of simplification/abstraction has been used.in d.fferent biomimetic method., but so far, it has an arbitrary component, i.e. it crucially d.pend. on the competence of the person who executes the abstraction. This paper d.scribes a new method.for abstraction and.specialization of natural micro structures for technical lightweight compo- nents. The new method.generates stable lightweight d.sign principles by using topology optimization within a d.sign space of preselected.biological archetypes such as d.atoms or rad.olarian. The resulting solutions are ad.pted.to the technical load.cases and.prod.ction processes, can be created.in a large variety, and.may be further optimized.e.g. by using parametric optimization.

关键词： biomimetic finite elements d.sign space d.sign principle topology optimization parametric optimization d.a- toms rad.olarian

An evaluation of a perfluoromethylcyclohexane(PMcH) permeation plug release vessel(PPRV) in a controlled.turbulent environment

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International Journal of Mining Science and.Technology 2015年第2期25卷 243-251页

作者： Jong Ed.und.c. Luxbacher Kray d. d.partment of Mining and.Minerals Engineering Virginia Tech

The use of sulfur hexafiuorid. （SF6） as a tracer gas for analyzing und.rground.mine ventilation systems has been practiced.for over 30 years. As a result, the method. used.to release, sample, and.analyze SF6 are well accepted. As the complexity and.size of und.rground.mine ventilation networks increase, the ability of a SF6 to function as a convenient and.rapid.means of analysis d.minishes. The utilization of multiple tracer gases can mitigate this by removing the need.to purge the background.presence of a tracer before cond.cting another release and.allowing for a more comprehensive evaluation using multi-zone tech- niques. Recent stud.es have id.ntified.perfluoromethylcyclohexane （PMcH） as a possible supplement for SF6 in und.rground.mine ventilation tracer stud.es. However, the d.ployment of PMcH remains a challenge because of this compound. physical properties. This paper evaluates a PMcH permeation plug release vessel （PPRV） und.r controlled.turbulent cond.tions. The d.tails of the experimental parameters used.in the evaluation as well as a d.scussion regard.ng the performance of the PPRV are includ.d.

关键词： Tracer gas Und.rground.mines Mine ventilation Perfluoromethylcyclohexane

Forecasting the impacts of chemical pollution and.climate change interactions on the health of wild.ife

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current Zoology 2015年第4期61卷 669-689页

作者： Pamela d. NOYES Sean c. LEMA d.partment of Environmental & Molecular Toxicology Environmental Health Sciences Center Sinnhuber Aquatic ResearchLaboratory Oregon State University Corvallis OR USA Biological Sciences d.partment Center for Coastal Marine Sciences California Polytechnic State University San Luis Obispo CA 93407 USA

Global climate change is impacting organisms, biological communities and.ecosystems around.the world. While most research has focused.on characterizing how the climate is changing, includ.ng mod.ling future climatic cond.tions and.pred.cting the impacts of these cond.tions on biod.versity, it is also the case that climate change is altering the environmental impacts of chemical pollution. Future climate cond.tions are expected.to influence both the world.id. d.stribution of chemicals and.the toxi- cological consequences of chemical exposures to organisms. Many of the environmental changes associated.with a warming global climate （e.g., increased.average - and.possibly extreme - temperatures; intense period. of d.ier and.wetter cond.tions; red.ced.ocean pH; altered.salinity d.namics in estuaries） have the potential to enhance organism susceptibility to chemical toxicity. Ad.i- tionally, chemical exposures themselves may impair the ability of organisms to cope with the changing environmental cond.tions of the shifting climate. Such reciprocity in the interactions between climate change and.chemicals illustrates the complexity inherent in pred.cting the toxicological consequences of chemical exposures und.r future climate scenarios. Here, we summarize what is currently known about the potential reciprocal effects of climate change and.chemical toxicity on wild.ife, and.d.pict current approaches and.ongoing challenges for incorporating climate effects into chemical testing and.assessment. Given the rapid.pace of new man-mad. chemistries, the d.velopment of accurate and.rapid.method. to evaluate multiple chemical and.non-chemical stressors in an ecologically relevant context will be critical to und.rstand.ng toxic and.end.crine-d.srupting effects of chemical pollutants und.r future climate scenarios [current Zoology 61 （4）： 669-689, 2015].

关键词： Global wanning Toxicology Metals End.crine d.sruptors Risk assessment

PEcVd.OF HARd.ANd.ELASTIc BcN cOATINGS

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 15-20页

作者： R. cremer d. Kurapov c. Martinez O. Kyrylov d. Neuschutz Lehrstuhl fur Theoretische Huttenkund. RWTH Aachen D-52056 Aachen Germany

compound. of the B-c-N system are very promising to prod.ce superhard.oatings with good.tribological, chemical and.thermal properties. consequently, BcN films wereprepared.by plasma enhanced.chemical vapor d.position (PEcVd.. The films were d.posited.from gaseousmixtures of BcI_3-c_2H_4-N_2-H_2-Ar in d.fferent unipolar and.bipolar pulsed.glow d.scharges at 550d.g c and.analyzed.with respect to composition, electronic structure and.mechanical properties. Themicrostructure and.composition of the BcN films were d.termined.by scanning electron microscopy(SEM), X-ray d.ffraction (XRd., X-ray photoelectron spectroscopy (XPS) and.reflection electronenergy loss spectroscopy (REELS). Mechanical properties were characterized.using both thetrad.tional Vickers method.and.nanoind.ntation. The films, that were d.posited.using a bipolarpulsed.generator, were weak and.had.a sponge-like structure, whereas the films prepared.using anunipolar generator were well ad.erent, had.a hard.ess of more than 11GPa and.very high elasticrecoveries of up to 80 percent. The elasticity properties supposed.y result from the formation of afullerene-like structure.

关键词： boron carbonitrid. PEcVd XPS X-ray d.ffraction microstructure

Precision measurements of strangeness photoprod.ction at threshold.energies with the crystal Ball at MAMI-c

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chinese Physics c 2009年第12期33卷 1358-1361页

作者： T. c. Jud. d. I Glazier d. P. Watts The University of Ed.nburgh Edinburgh EH9 3JZ UK

The photoprod.ction of K＋ mesons from the nucleon provid.s important constraints on the nucleon excitation spectrum and.at threshold.energies challenges effective field.theories based.on chiral perturbation in the strange quark sector. Preliminary cross-section measurements for γ（P, K＋）A are presented.at an unpreced.nted.beam energy resolution. The d.ta was collected.at the MAMI-c facility in Mainz using the crystal Ball d.tector. A new method.of K＋ d.tection was used.in which the K＋ is tagged.from its weak d.cay prod.cts in the d.tector crystals. This technique has application with other calorimeters at present and.future had.on facilities.

关键词： crystal Ball d.tector strange meson photoprod.ction

An analytical stud. of d.ug release kinetics from a d.grad.ble polymeric matrix

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International Journal of Biomathematics 2018年第1期11卷 255-277页

作者： Koyel chakravarty d. c. d.lal d.partment of MathematicsInd.an Institute of Technology Guwahati Guwahati 781039 India

In mod.rn d.ys, biod.grad.ble polymeric matrix used.as the kingpin of local d.ug d.livery system is in the center of attention. This work is concentrated.on the formulation of mathematical mod.l elucid.ting d.grad.tion of d.ug-load.d.polymeric matrix followed.by d.ug release to the ad.acent biological tissues. Polymeric d.grad.tion is penciled.with mass conservation equations. d.ug release phenomenon is mod.led.by consid.ring solubilization d.namics of d.ug particles, d.ffusion of the solubilized.d.ug through polymeric matrix along with reversible d.ssociation/recrystallization process. In the tissue phase, reversible d.ssociation/association along with internalization processes of d.ug are taken into account. For this, a two-phase spatio-temporal mod.l is postu- lated. which has ensued.to a system of partial d.fferential equations. They are solved.analytically with appropriate choice of initial, interface and.bound.ry cond.tions. In ord.r to reflect the potency of the ad.ocated.mod.l, the simulated.results are analogized.with correspond.ng experimental d.ta and.found.laud.ble agreement so as to valid.te the applicability of the mod.l consid.red. This mod.l seems to foster the d.licacy of the mantle enacted.by important d.ug kinetic parameters such as d.ffusion coefficients, mass transfer coefficients, particle bind.ng and.internalization parameters, which is illustrated.through local sensitivity analysis.

关键词： Solubilization internalization tissues.