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Heat Transfer Model with Two Heat Transfer Coefficients Along a M ultiperforated Plate-Application to Combustion Chamber Wall Cooling

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Journal of Thermal Science 2003年第4期12卷 363-366页

作者： Brice Petre Eva dorignac jean jacques Vullierme Laboratoire d'Etudes Thermiques U.M.R C.N.R.S 6608-ENSMA BP 40109 86961 Futuroscope Chasseneuil Cedex FRANCELaboratoire d'Etudes Thermiques U.M.R C.N.R.S 6608-ENSMA BP 40109 86961 Futuroscope Chasseneuil Cedex FRANCELaboratoire d'Etudes Thermiques U.M.R C.N.R.S 6608-ENSMA BP 40109 86961 Futuroscope Chasseneuil Cedex FRANCE

Walls' cooling of aeronautic propeller combustion chamber is performed with the injection, through the combustion chamber wall, of a part of the air coming from compressors placed upstream. Measurements of the wall thermal fields are made by infrared thermography along the injection wall. This injection wall is pierced by 9 rows of 8 holes (α=90°) in staggered configuration (p/d=s/d=6). We propose a model using two heat transfer coefficients to represent the convective exchanges. The results are non-dimensioned and presented in comparison with the case without holes. The use of this model allows us to define 4 zones. Those 4 zones exist for the 5 blowing rates.

关键词： multiperforation cooling heat transfer coefficients infrared thermography.

Soil Macrofaunal Communities are Heterogeneous in Heathlands with different Grazing Intensity

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Pedosphere 2015年第4期25卷 524-533页

作者： jean-Franois PONGE Sandrine SALMON Amélie BENOIST jean-jacques GEOFFROY Muséum National d’Histoire Naturelle CNRS UMR 7179 4 avenue du Petit Chteau 91800 Brunoy (France) Muséum National d’Histoire Naturelle CNRS UMR 7204 4 avenue du Petit Chteau 91800 Brunoy (France)

Moderate grazing by cattle increases the heterogeneity of soil and vegetation. This has been suggested as an ecologically sustainable mean of managing natural environments endangered by tree encroachment, such as heathlands. Our study was performed to test the impact of grazing intensity on soil macroinvertebrate communities in heterogeneous landscapes in a private property eligible to the Natura 2000 European Network of Special Protection Areas within the Brenne Natural Regional Park （Indre, ~rance）. We sampled macroinvertebrates along a broken line crossing 5 different land-use types, from pasture to pine forest, passing through a besom heath （Erica scoparia） heathland at 3 levels of cattle pressure. We hypothesized that： i） litter-dwelling （mostly arthropods and mollusks） and soil-dwelling macroinvertebrates （mostly earthworms） would respond in an opposite manner to various grazing intensities, and ii） intermediate cattle pressure （pastured heath） would increase soil and community heterogeneity. The results supported the first hypothesis, which was explained by land-use impacts mediated by soil properties. However, our results supported only partly the second hypothesis since maximum dissimilarity （whether in the composition of soil macroinvertebrate communities or in soil features） was observed in only one out of the two pastured heaths where cattle pressure was intermediate.

关键词： besom heath cattle grazing heterogeneity land-use types soil macroinvertebrates

Effects of aging on the microstructures and mechanical properties of extruded AM50+xCa magnesium alloys

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Rare Metals 2006年第4期25卷 377-381页

作者： WANG Qudong PENG Jianguo Suéry Michel jean-jacques Blandin National Engineering Research Centre of Light Alloys Net Forming School of Materials Science and Engineering Shanghai Jiaotong UniversityShanghai 200030 China Institute National Polytechnique de Grenoble （INPG） Génie Physique et Mécanique des Matériaux （GPM2） UMR CNRS 5010 ENSPG BP46 38402 Saint-Martin d＇Héres Cedex France

The effects of aging treatment on the microstructures and mechanical properties of extruded AM50 ＋ xCa alloys （x=0, 1, 2 wt.%） were studied. The results indicated the secondary phase Mgl7Al12 precipitated from the saturated α-Mg solid solution while Al2Ca changed slightly when the aging time was increased. The hardness of extruded AM50 ＋ xCa al- loys increased initially to its peak, and then dropped to reach its original hardness with the increase in aging time. With the increase in aging temperature, the hardness of the AM50 ＋ 2Ca ahoy decreased, whereas the hardness of AM50 and AM50 ＋ 1Ca alloys decreased in the initial stages of aging treatment and increased in the later stages of aging treatment. The tensile strengths of AM50 and AM50 ＋ 1Ca alloys increased after aging treatment for the precipitation of Mg17Al12 phase, which increases the resistance against dislocation movement at the grain boundary; with increase in aging temperature, their tensile strengths increased. For AM50 ＋ 2Ca alloy, the tensile strength declined after aging at 150℃ and 175℃, while it increased slightly at 200℃. The ductility of AM50 ＋ xCa alloys （x = 0, 1, 2 wt.%） declined after aging treatment.

关键词： AM50 + xCa alloys aging extrusion mechanical properties

Model-independent constraints on spin observables

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Chinese Physics C 2009年第12期33卷 1153-1158页

作者： jean-Marc Richard Xavier Artru Mokhtar Elchikh jacques Soffer Oleg Teryaev LPSC Université Joseph Fourier CNRS/IN2P3 INPG Grenoble France Université de Lyon IPNL Université Lyon 1 and CNRS/IN2P3 Villeurbanne France Université des Sciences et de Technologie d'Oran El Menauoer Oran Algeria Physics department Temple University Philadelphia PA 19122 -6082 USA Bogoliubov Laboratory of Theoretical Physics JINR 141980 Dubna Russia

We discuss model-independent constraints on spin observables in exclusive and inclusive reactions, with special attention to the case of photoproduction.

关键词： spin observables positivity exclusive reactions inclusive reactions

Mid-infrared Ⅲ-Ⅴ semiconductor lasers epitaxially grown on Si substrates

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Light(Science & Applications) 2022年第7期11卷 1366-1378页

作者： Eric Tournié Laura Monge Bartolome Marta Rio Calvo Zeineb Loghmari daniel A.d.az-Thomas Roland Teissier Alexei N.Baranov Laurent Cerutti jean-Baptiste Rodriguez IES University of MontpellierCNRS34000 MontpellierFrance

There is currently much activity toward the integration of mid-infrared semiconductor lasers on Si substrates for developing a variety of smart,compact,sensors based on Si-photonics integrated *** review this rapidly-evolving research field,focusing on the epitaxial integration of antimonide lasers,the only technology covering the whole mid-to-far-infrared spectral *** explain how a dedicated molecular-beam epitaxy strategy allows for achieving high-performance GaSb-based diode lasers,InAs/AlSb quantum cascade lasers,and InAs/GaInSb interband cascade lasers by direct growth on on-axis(001)Si substrates,whereas GaAs-on-Si or GaSb-on-Si layers grown by metal-organic vapor phase epitaxy in large capability epitaxy tools are suitable templates for antimonide laser *** also show that etching the facets of antimonide lasers grown on Si is a viable approach in view of photonic integrated ***,this review shows that while diode lasers are sensitive to residual crystal defects,the quantum cascade and interband cascade lasers grown on Si exhibit performances comparable to those of similar devices grown on their native substrates,due to their particular band structures and radiative recombination *** device lifetimes have been extrapolated for interband cascade ***,routes to be further explored are also presented.

关键词： epitaxial quantum template

Surface oxidation of Ni-cermet electrodes by CO_(2) and H_(2)O and how to moderate it

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Journal of Energy Chemistry 2022年第4期31卷 300-308页

作者： dingkai Chen Mathias Barreau Thierry dintzer Sylwia Turczyniak-Surdacka Fabrice Bournel jean-jacques Gallet Spyridon Zafeiratos Institut de Chimie et Procédés pour l’Energie l’Environnement et la SantéUMR 7515 CNRS-UdS25 Rue Becquerel67087 StrasbourgFrance Faculty of Chemistry Biological and Chemical Research CentreUniversity of WarsawŻwirki i Wigury 10102-089 WarsawPoland Faculty of Chemistry University of WarsawPasteura 102-093Poland Laboratoire de Chimie Physique-Matière et Rayonnement Sorbonne UniversitéCampus CurieCNRS UMR 76144 place Jussieu75005 ParisFrance Synchrotron SOLEIL L’orme des MerisiersB.P.48Saint AubinGif-sur-Yvette Cedex 91192France

The oxidation of porous Ni-yttria-stabilized zirconia(YSZ)and Ni-gadolinia-doped ceria(GdC)ceramicmetal(cermet)electrodes in H_(2)O and CO_(2)atmospheres was studied by near-ambient pressure X-ray photoelectron spectroscopy(NAP-XPS).We show that the oxidation of nickel by the two gases is not similar,as is commonly believed,but it depends on the ceramic *** is vulnerable to oxidation in H_(2)O but it resists to CO_(2)in Ni-GdC,as compared to the Ni-YSZ *** by this observation we conceptualize and fabricate Ni-YSZ electrodes modified by ceria nanoparticles,which show significantly higher resistance to CO_(2)oxidation as compared with conventional Ni-YSZ *** preparation of tailormade cermet electrodes with identical bulk/mechanical characteristics but very different surface properties offers a promising fabrication strategy for high-performance and durability solid oxide electrolysis cells for CO_(2)conversion.

关键词： NAP-XPS CO_(2)electrolysis Nickel oxidation Solid oxide cells Ceria nanoparticles

Application of in-situ characterization techniques in modern aqueous batteries

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Rare Metals 2024年第8期43卷 3553-3575页

作者： Jia-Hao Wu Hong-Wei Cai Zhao-Hui deng jean-jacques Gaumet Yu Bao Wen Luo department of Physics State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingSchool of Materials Science and EngineeringWuhan University of TechnologyWuhan430070China Laboratoire de Chimie Et Physique:Approche Multi-Echelles Des Milieux Complexes(LCP-A2MC)Institut Jean BarriolUniversitéde Lorraine57070MetzFrance department of Medicinal Chemistry Hubei College of Chinese MedicineJingzhou 434020China

The development of high-performance aqueous batteries calls for an in-depth knowledge of their chargedischarge redox and failure mechanism,as well as a systematic understanding of the dynamic evolution of microstructure,phase composition,chemical composition,and local chemical environment of the materials for ***-situ characterization technology is expected to understand and reveal the problems faced by aqueous rechargeable batteries,such as the dissolution of electrode materials,the growth of metal negative electrode dendrites,passivation,corrosion,side reactions and a series of *** on this,typical in-situ characterization techniques and their basic mechanisms are summarized,including in-situ optical visualization,in-situ microscopy techniques(in-situ scanning electron microscopy(SEM),in-situ transmission electron microscopy(TEM)),in-situ X-ray techniques(in-situ X-ray diffraction(XRd),in-situ X-ray photoelectron spectroscopy(XPS),in-situ near-edge structural X-ray absorption spectroscopy(XANES)),and in-situ spectroscopy techniques(in-situ Raman spectroscopy,in-situ Fourier transform infrared(FTIR)).Moreover,some emerging techniques concerning aqueous battery research,especially gas evolution and materials dissolution issues,such as in-situ electrochemical quartz crystal microbalance(EQCM).in-situ fiber-optic sensing,in-situ gas chromatography(GC) are *** last,the applications of advanced in-situ characterizations in future research of aqueous batteries are emphasized and discussed,along with some of the remaining challenges and possible solutions.

关键词： Aqueous battery In-situ characterization Phase transformation Solid electrolyte interphase Zinc dendrite growth

Encapsulating segment-like antimony nanorod in hollow carbon tube as long-lifespan,high-rate anodes for rechargeable K-ion batteries

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Nano Research 2019年第5期12卷 1025-1031页

作者： Wen Luo Feng Li Weiran Zhang Kang Han jean-jacques Gaumet Hans-Eckhardt Schaefer Liqiang Mai department of Physics School of ScienceWuhan University of TechnologyWuhan 430070China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230000China division of Materials Science and Engineering Boston UniversityMA 02215USA State Key Laboratory of Advanced Technology for Materials Synthesis and Processing International School of Materials Science and Technology Wuhan University of TechnologyWuhan 430070China Laboratoire de Chimie et Physique: Approche Multi-echelles des Milieux Complexes Institut Jean BarriolUniversite de LorraineMetz 57070France Institute for Functional Matter and Quantum Technologies Stuttgart UniversityPfaffenwaldring 57Stuttgart 70569Germany

K-ion battery (KIB) is a new-type energy storage device that possesses potential advantages of low-cost and abundant resource of *** develop advanced electrode materials for accommodating the large size and high activity of potassium ion is of great ***,a segment-like antimony (Sb) nanorod encapsulated in hollow carbon tube electrode material (Sb@HCT) was *** from the virtue of abundant nitrogen doping in carbon tube,one-dimensional and hollow structure advantages,Sb@HCT exhibits excellent potassium storage properties:in the case of potassium bis(fluorosulfonyl)imide (KFSI) electrolyte,Sb@HCT displays a reversible capacity of up to 453.4 mAh·g^-1 at a current density of 0.5 A·g^-1 and good rate performance (a capacity of 211.5 mAh·g^-1 could be achieved at an ultrahigh rate of 5 A·g^-1).Additionally,Sb@HCT demonstrates excellent long-cycle stability at a current density of 2 A·g^-1 over 120 ***,electrolyte optimization is an effective strategy for greatly improving electrochemical *** ex-situ characterizations,we disclosed the potassiation of Sb anode is quite reversible and undergoes multistep processes,combining solid solution reaction and two-phase reaction.

关键词： K-ion battery antimony anode hollow carbon tube encapsulation electrolyte optimizati on potassium storage mechanism

Preparation of a Slow Release Biofertilizer From a Polymeric Urea-Formaldehyde Matrix (PUFM)

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Phyton-International Journal of Experimental Botany 2019年第4期88卷 459-470页

作者： Laura Siverio Martínez Mayra González Hurtado Laura M.Castro González jacques Rieumont Briones Ariel Martínez García María I.Hernández d.az Institute of Materials Science and Technology Polymer LaboratoryUniversity of HavanaZapata and GC.P.10400C.Havana CityCuba National Autonomous University of Mexico Department of Physical and Theoretical Chemistry CoyoacanDistrito FederalMX Faculty of Chemistry University of HavanaDepartment of Physical ChemistryZapata and GC.P.10400Havana CityCuba Institute of Horticultural Research Liliana dimitrova Quivicánkm 33½.Havana CityCuba

Fertilizers industry faces the challenge of improving the efficiency of its products either by optimizing the fertilizers in use or by developing new types of *** the last decade,controlled and slow release technologies have become more *** technologies aim to increase the efficiency of the applied substance by increasing its action over time and avoiding losses of all kinds(leaching,volatilization).The main purpose of the current study was to obtain a slow release biofertilizer by incorporating microalgae into a polymeric urea-formaldehyde matrix(PUFM).The quantitative analysis of macronutrients and micronutrients in the microalgae was determined using different techniques including titration,UV and Atomic Adsorption *** matrix and the formulation obtained(PUFM+CHLO)were also characterized by Infrared Spectroscopy(FTIR)and Scanning Electron Microscopy(SEM).The“in vitro”study showed a typical slow release behavior of nitrogen(N),phosphorus(P)and potassium(K)*** was also shown that(PUFM+CHLO)formulation has the slowest macronutrients release time with a maximum release of 28%,26%y 46%for(N-P-K)macronutrients respectively during a period of 30 ***"in vivo"study exposed the benefits of the biofertilizer formulation(PUFM+CHLO)from conventional commercial fertilizer(CF)(NPK-14-5-12).due to the presence of nutrients of natural origin in microalgae,(PUFM+CHLO)shows ecological effects which could also developing sustainable agriculture systems.

关键词： Slow-release fertilizer microalgae polymeric matrix nutrients