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Acta Metallurgica Sinica(English Letters) 2014年第4期27卷 714-722页

作者： Hiroki Kurita Emilien Feuillet Thomas Guillemet jean-Marc Heintz Akira Kawasaki jean-Francois Silvain DEN/DANS/DMN/SRMA/LTMEx CEA SaclayGif-sur-YvetteFrance Institute of Condensed Matter Chemistry of Bordeaux BordeauxFrance Department of Materials Processing Graduate School of EngineeringTohoku University

The constant increase in power and heat flux densities encountered in electronic devices fuels a rising demand for lightweight heat sink materials with suitable thermal *** this study,discontinuous pitch-based carbon fiber reinforced aluminum matrix（Al-CF） composites with aluminum–silicon alloy（Al–Si） were fabricated through hot *** small amount of Al–Si contributed to enhance the sintering process in order to achieve fully dense Al–CF composites.A thermal conductivity and CTE of 258 W/（m K） and 7.0 9 10-6/K in the in-plane direction of the carbon fibers were obtained for a（Al95 vol%＋ Al–Si5 vol%）-CF50 vol%*** fiber provides the reducing of CTE while the conservation of thermal conductivity and weight of *** achieved CTEs satisfy the standard requirements for a heat sink material,which furthermore possess a specific thermal conductivity of 109 W cm3/（m K g）.This simple process allows the low-cost fabrication of Al–CF composite,which is applicable for a lightweight heat sink material.

关键词： Carbon fiber Metal-matrix composites(MMCs) Thermal properties Powder processing

Nonlinear dynamic behavior of inhomogeneous functional plates composed of sigmoid graded metal-ceramic materials

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Science China(Technological Sciences) 2018年第11期61卷 1654-1665页

作者： WANG YanQing ZU jean W. Department of Mechanics Northeastern University Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern University Department of Mechanical and Industrial Engineering University of Toronto

This paper presents a study on nonlinear vibration of inhomogeneous functional plates composed of sigmoid graded metalceramic materials. The material properties vary continuously along the thickness direction according to a sigmoid distribution rule, which is defined by piecewise functions to ensure smooth distribution of stress among all the interfaces. The geometric nonlinearity is considered by adopting the von Kármán geometrical relations. Based on the d'Alembert's principle, the nonlinear out-of-plane equation of motion of the plates is developed. The Galerkin method is employed to discretize the motion equation to a series of ordinary differential ones, which are subsequently analyzed via the use of the method of harmonic balance. Then, the analytical results are validated by the comparison to numerical solutions, which are obtained by using the adaptive step-size fourth-order Runge-Kutta method. The stability of the steady-state response is examined by the perturbation technique. Results show the first and third modes are both activated while the second mode is not activated for the plates under harmonic point excitation. The frequency response relationships of activated modes exhibit very complicated curves due to the nonlinear modal interaction. In addition, influences of key system parameters on nonlinear vibrational characteristics of the present inhomogeneous plates are illustrated.

关键词： inhomogeneous functional plates sigmoid graded metal-ceramic material nonlinear vibration response harmonic balance method

Modeling of 3-D Losses and Deviations in a Throughflow Analysis Tool

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Journal of Thermal Science 2007年第3期16卷 208-214页

作者： jean-Fran■ois Simon OlivierLéonard Techspace Aero-Aerodynamic Group University

This contribution is dedicated to the modeling of the end-wall flows in a throughflow model for turbomachinery applications. The throughflow model is based on the Euler or Navier-Stokes equations solved by a Finite-Volume technique. Two approaches are presented for the end-wall modeling. The first one is based on an inviscid formulation with dedicated 3-D distributions of loss coefficient and deviation in the end-wall regions. The second approach is directly based on a viscous formulation with no-slip boundary condition along the annular end-walls and blade force modification in the region close to the end-walls. The throughflow results are compared to a series of 3-D Navier-Stokes calculations averaged in the circumferential direction. These 3-D calculations were performed on the three rotors of a low pressure axial compressor, for a series of tip clearance values.

关键词： throughflow losses deviations axial compressors

G~n filling orbicular N-sided holes using periodic B-spline surfaces

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Science China(Information Sciences) 2011年第7期54卷 1383-1394页

作者： PAUL jean-Claude School of Software Tsinghua University Key Laboratory for Information System Security Ministry of Education of China Tsinghua National Laboratory for Information Science and Technology Institute National de Recherche en Informatique et en Automatique

The orbicular N -sided hole filling problem is usually introduced by filleting an end-point of a part with large *** existing methods based on quadrilateral partition or constrained-optimization can rarely generate high-order continuous blending surfaces under these *** paper first reparameterizes the boundary of the specified orbicular N -sided hole to ensure the compatibility of neighboring cross-boundary derivatives on the connecting points,preserving their G n *** we compute the control points of the periodic B-spline surface using the sufficient G n continuity condition on the pole and the algorithm of extending parametric *** method generates single blending surface,which can be converted into standard Bspline surface by adding knots without introducing *** only elevates the degree of the boundary by *** construction method is simple and efficient,without iteration nor large-scale matrix *** achieves G n continuity under compatible *** blending examples underline its feasibility and practicability.

关键词： CAD periodic B-spline surface polar coordinates N -sided hole filling G n continuity

Multiplexing technology for in vitro diagnosis of pathogens： the key contribution of phosphorus dendrimers

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Science China Materials 2018年第11期61卷 1454-1461页

作者： jean Pierre Majoral jean Marie Francois Richard Fabre Alice Senescau Serge Mignani Anne-Marie Caminade Laboratoire de Chimie de Coordination du CNRS 31077 Toulouse Cedex 4France LCC-CNRS Universit6 de Toulouse CNRSToulouseFrance Dendris 31670 LabegeFrance LISBP UMR CNRS 5504 INRA 79231077 Toulouse Cedex 04France Universite Paris Descartes PRES Sorbonne Paris Cite CNRS-UMR 860Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicolgique75006 ParisFrance

After the microbiology based on Pasteur's method and polymerase chain reaction(PCR), the diagnosis company named Dendris has proposed a third-generation of diagnosis enabling the search of a broad range of pathogens with strong sensitivity and specificity. This extraordinary profile was possible thanks to the use of phosphorus dendrimers for which various techniques of deposition on a given support were investigated and described and analyzed in this report.

关键词： phosphorus dendrimers diagnosis DNA arrays multiplexing technology

Experimental and Statistical Analysis of Fatigue Behavior in Zr-based Bulk Metallic Glass

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稀有金属材料与工程 2024年第11期53卷 3010-3016页

作者： Yao Zhifeng Qiao Jichao Pelletier jean-Marc Yao Yao School of Civil Engineering Xi'an University of Architecture&TechnologyXi'an 710055China Dongguan Sanhang Innovation Institute Dongguan 523808China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China Institut National des Sciences Appliquées de Lyon Universitéde LyonLyon F-69621France School of Materials and Chemical Engineering Xi'an Technological UniversityXi'an710021China

Three-point bending fatigue experiments were conducted on a typical Zr-based bulk metallic glass(BMG)at ambient temperature to investigate the fatigue behavior under cyclic loading *** show that the stress amplitude-cycles to failure(S-N)curve of the Zr-based BMG is determined,and the fatigue endurance limit is 442 MPa(stress amplitude).To evaluate the probability-stress amplitude-cycles to failure(P-S-N)curve,an estimation method based on maximum likelihood was proposed,which relies on statistical principles to estimate the fatigue life of the material and allows for a reduction in the number of samples required,offering a cost-effective and efficient alternative to traditional testing *** experimental results align with the American Society for Testing and Materials(ASTM)standard,indicating the reliability and accuracy of this estimation method in evaluating the fatigue behavior of Zr-based BMG.

关键词： bulk metallic glass P-S-N curve fatigue test statistical analysis

A new non-specificity measure in evidence theory based on belief intervals

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Chinese Journal of Aeronautics 2016年第3期29卷 704-713页

作者： Yang Yi Han Deqian jean Dezert SKLSVMS School of AerospaceXi'an Jiaotong UniversityXi'an 710049China Center for Information Engineering Science Research Xi'an Jiaotong UniversityXi'an 710049China ONERA The Freneh Aerospace LabChemin de la HunireF-91761 PalaiseauFrance

In the theory of belief functions, the measure of uncertainty is an important concept, which is used for representing some types of uncertainty incorporated in bodies of evidence such as the discord and the non-specificity. For the non-specificity part, some traditional measures use for reference the Hartley measure in classical set theory; other traditional measures use the simple and heuristic function for joint use of mass assignments and the cardinality of focal elements. In this paper, a new non-specificity measure is proposed using lengths of belief intervals, which represent the degree of imprecision. Therefore, it has more intuitive physical meaning. It can be proved that our new measure can be rewritten in a general form for the non-specificity. Our new measure is also proved to be a strict non-specificity measure with some desired properties. Numerical examples, simulations, the related analyses and proofs are provided to show the characteristics and good properties of the new non-specificity definition. An example of an application of the new non- specificity measure is also presented.

关键词： Belief interval Evidence theoryImprecision Non-specificity Uncertainty

Basic belief assignment approximations using degree of non-redundancy for focal element

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Chinese Journal of Aeronautics 2019年第11期32卷 2503-2515页

作者： Yi YANG Deqiang HAN jean DEZERT SKLSVMS School of AerospaceXi'an Jiaotong UniversityXi'an 710049China Center for Information Engineering Science Research XVan Jiaotong UniversityXi'an 710049China ONERA The French Aerospace LabChemin de la HunierePalaiseau F-91761France

Dempster-Shafer evidence theory, also called the theory of belief function, is widely used for uncertainty modeling and reasoning. However, when the size and number of focal elements are large, the evidence combination will bring a high computational complexity. To address this issue,various methods have been proposed including the implementation of more efficient combination rules and the simplifications or approximations of Basic Belief Assignments(BBAs). In this paper,a novel principle for approximating a BBA into a simpler one is proposed, which is based on the degree of non-redundancy for focal elements. More non-redundant focal elements are kept in the approximation while more redundant focal elements in the original BBA are removed first. Three types of degree of non-redundancy are defined based on three different definitions of focal element distance, respectively. Two different implementations of this principle for BBA approximations are proposed including a batch and an iterative type. Examples, experiments, comparisons and related analyses are provided to validate proposed approximation approaches.

关键词： BBA approximation Belief functions Evidence theory Focal element Non-redundancy

Effects of indole-3-butyric acid and age of stem cuttings on root morphology,growth,and survival of Cornus sericea

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Journal of Forestry Research 2023年第2期34卷 433-440页

作者： Sahari Inoue Chibuzo Ilogu jean-Marie Sobze Northern Alberta Institute of Technology Centre for Boreal ResearchPeace RiverAB T8S 1R2Canada Fine Phenotyping Lab Crop Health and ProtectionHarpenden AL52JQUK

Red osier dogwood(Cornus sericea L.),widely distributed throughout North America,is essential for wildlife,thus *** is recommended for reclamation or revegetation of sites disturbed by oil and gas extraction because it tolerates a wide range of soil types and high pH *** germination of this species is extremely difficult with long stratification requirements and poor germination,cuttings facilitate *** this study,to develop techniques to propagate the species from stem cuttings,four concentrations of indole-3-butyric acid(IBA)and two cutting ages previous year’s growth(PYG)and current year’s growth(CYG)were investigated for survival and *** 4 months,survival rate,height growth,and shoot biomass from PYG cuttings were enhanced with IB *** contrast,IB A did not affect these parameters in CYG *** morphology was significantly affected by IB A concentration and cutting ***,at higher concentrations,increased root surface and *** root surface area and length of PYG cuttings were increased,which may facilitate the absorption of essential resources and consequently increase *** results indicate that increasing the concentration of IB A may be an effective way to have better plant survival and growth of previous year’s cuttings in red osier dogwood.

关键词： Vegetative propagation IBA Chronological age Cornus sericea L. Survival rate

Accumulation of Flavonoids in an ntra ntrb Mutant Leads to Tolerance to UV-C

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Molecular Plant 2009年第2期2卷 249-258页

作者： Talaat Bashandy Ludivine Taconnat jean-Pierre Renou Yves Meyer jean-Philippe Reichheld Laboratoire Genome et Developpement des Plantes Universite de Perpignan UMR CNRS 5096 52 avenue Paul Alduy 66860 Perpignan France Unite de Recherche en Genomique Vegetale 91057 Evry cedex France

NADPH-dependent thioredoxin reductases （NTRs） are key regulatory enzymes determining the redox state of thioredoxins. There are two genes encoding NTRs （NTRA and NTRB） in the Arabidopsis genome, each encoding a cytosolic and a mitochondrial isoform. A double ntra ntrb mutant has recently been characterized and shows slower plant growth, slightly wrinkled seeds and a remarkable hypersensitivity to buthionine sulfoximine （BSO）, a specific inhibitor of gluta- thione biosynthesis. In this paper, we demonstrate that this mutant also accumulates higher level of flavonoids. Analysis of transcriptome data showed that several genes of the flavonoid pathway are overexpressed in the ntra ntrb mutant. Accumulation of flavonoids is generally considered a hallmark of plant stress. Nevertheless, no elevation of the expression of genes encoding ROS-detoxification enzymes was observed, suggesting that the ntra ntrb plants do not suffer from oxidative disease. Another hypothesis suggests that flavonoids are specifically synthesized in the ntra ntrb mutant in order to rescue the inactivation of NTR. To test this, the ntra ntrb mutant was crossed with transparent testa 4 （tt4） plants with a mutation in the gene encoding the first enzyme in flavonoid biosynthesis. As ntra ntrb plants are more resistant to UV-C treatment than wild-type plants, this higher resistance was abolished in the ntra ntrb tt4 mutant, suggesting that accumulation of flavonoids in the ntra ntrb mutant protects plants against UV-light.

关键词： abiotic/environmental stress oxidative and photo-oxidative stress secondary metabolism - phenylpropanoidsand phenolics gene expression Arabidopsis.