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EIGENVALUES OF THE NEUMANN-POINCARE OPERATOR FOR TWO INCLUSIONS WITH CONTACT OF ORDER m： A NUMERICAL STUDY

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Journal of Computational mathematics 2018年第1期36卷 17-28页

作者： Eric Bonnetier Faouzi Triki Chun-Hsiang Tsou Universitd Grenoble-Alpes//cnrS Laboratoire Jean Kuntzraann UMR 5224 Grenoble F-38041 France

In a composite medium that contains close-to-touching inclusions, the pointwise values of the gradient of the voltage potential may blow up as the distance S between some inclusions tends to 0 and as the conductivity contrast degenerates. In a recent paper [9], we showed that the blow-up rate of the gradient is related to how the eigenvalues of the associated Neumann-Poincare operator converge to ±1/2 as δ→ 0, and on the regularity of the contact. Here, we consider two connected 2-D inclusions, at a distance 5 〉 0 from each other. When δ=0, the contact between the inclusions is of order m 〉 2. We numerically determine the asymptotic behavior of the first eigenvalue of the Neumann- Poincare operator, in terms of 5 and rn, and we check that we recover the estimates obtained in [10].

关键词： Elliptic equations Eigenvalues Numerical approximation.

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

Inf-convolution of G-expectations

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Science China mathematics 2010年第8期53卷 1957-1970页

作者： BUCKDAHN Rainer laboratoire de math'ematiques CNRS-UMR 6205Universite' de Bretagne Occidentale

In this paper we will discuss the optimal risk transfer problems when risk measures are generated by G-expectations,and we present the relationship between inf-convolution of G-expectations and the infconvolution of d... 详细信息

关键词： inf-convolution G-expectation G-normal distribution G-Brownian motion

The Apollon 10 PW laser: experimental and theoretical investigation of the temporal characteristics

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High Power Laser Science and Engineering 2016年第3期4卷 127-133页

作者： D.N.Papadopoulos J.P.Zou C.Le Blanc G.Chriaux P.Georges F.Druon G.Mennerat P.Ramirez L.Martin A.Frneaux A.Beluze N.Lebas P.Monot F.mathieu P.Audebert laboratoire pour l'Utilisation des Lasers Intenses CNRSEcole Polytechnique laboratoire Charles Fabry UMR 8501 Institut d'OptiqueCNRS Univ Paris Sud CEA Iramis SPAM

The objective of the Apollon 10 PW project is the generation of 10 PW peak power pulses of 15 fs at 1 shot min^(-1). In this paper a brief update on the current status of the Apollon project is presented, followed by a more detailed presentation of our experimental and theoretical investigations of the temporal characteristics of the laser. More specifically the design considerations as well as the technological and physical limitations to achieve the intended pulse duration and contrast are discussed.

关键词： high intensity lasers spatiotemporal effects ultrafast lasers

Performance Evaluation of Solar Chimney Draft: Application to Ventilation

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Smart Grid and Renewable Energy 2024年第4期15卷 107-122页

作者： Boukaré Ouedraogo Adama Ouedraogo Arouna Kabore Kalifa Palm Dieudonné Joseph Bahiebo laboratoire dEnergies Thermiques Renouvelables (LETRE) Universit Joseph KI-ZERBO: UFR/SEA Ouagadougou Burkina Faso laboratoire de Chimie Analytique Physique Spatiale et Energtique (LACAPSE) Universit Norbert ZONGO Koudougou Burkina Faso Centre Universitaire Polytechnique de Kaya (CUP-Kaya) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso laboratoire des Systmes dEnergie Renouvelable et Environnement Institut de Recherche en Sciences Appliques et Technologies (IRSAT) Centre National de la Recherche Scientifique et Technologique (CNRST) Ouagadougou Burkina Faso

Ventilation is one of the factors contributing to energy consumption in buildings and food preservation. The solar chimney proves to be an alternative for reducing conventional energy consumption. Thus, in this study, the performance of a solar chimney with two active faces for thermally drawing air from a chamber for preserving agri-food products was evaluated. These performances were experimentally assessed through data measurements: temperatures and velocities within the chimney, and their analysis using Excel and matLAB. The obtained results were compared with those from literature to verify their validity. From this study, it is found that the maximum temperature at the chimney outlet reaches 49.4˚C with an average value of 43.7˚C. Additionally, the heating evolution of the chimney air presents four (04) identical phases in pairs, reflecting the chimney’s operation throughout day. The temperature difference between the outlet and inlet of the chimney reaches a maximum of 17˚C with an average of 12.6˚C. Regarding airflow, the maximum air velocity at the chimney outlet is 0.8 m/s, and the average velocities have consistently been greater than or equal to 0.46 m/s. Thus, it can be concluded that the solar chimney is capable of providing ventilation for the preservation chamber through thermal draft.

关键词： Solar Chimney Natural Ventilation Thermal Draft Airflow Chimney Effect

Influences of graphene nanoplatelet aspect ratio and thermal treatment on dielectric performances of poly(methyl methacrylate)composites

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High Voltage 2016年第4期1卷 146-150页

作者： Benhui Fan Yu Liu Delong He Jinbo Bai laboratoire Mécanique des Sols Structures et Matériaux(MSSMat)CNRS UMR 8579Ecole CentraleSupelecUniversitéParis SaclayGrande Voie des Vignes92290 Chatenay-MalabryFrance

The dielectric property and percolated behaviour of polymer matrix composites largely depend on the morphology of conductive fillers and external stimulations especially when the composites are processed by melting blending and extrusion-injection *** this study,the poly(methyl methacrylate)(PMMA)matrix composites incorporated by two kinds of graphene nanoplatelets(GNP),G5 and G150 with different aspect ratios(the ratio of diameter and thickness)are prepared to study the influence of GNP morphology on the dielectric performances close to percolation threshold(f_(c)).After annealing at glass transition temperature(T_(g))for 1 h,the dielectric permittivities of PMMA/G5 and PMMA/G150 near fc increase 43 and 38%,respectively,while the dielectric loss change *** improvement on the dielectric property is possibly attributed to the slight change of the distance between adjacent GNPs after annealing at T_(g)which enables to arouse stronger polarisation by tunnelling effect.

关键词： composites dielectric property

Ar^+/Ar, O_2^+/O_2 and N_2^+/N_2 Elastic Momentum Collision Cross Sections: Calculation and Validation Using the Semi-Classical Model

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Plasma Science and Technology 2014年第6期16卷 588-592页

作者： Djilali BENYOUCEF Mohammed YOUSFI laboratoire Génie Electrique et Energies Renouvelables Chlef University Universitéde Toulouse LAPLACE UMR CNRS

The aim of this paper is to obtain relevant sets of collision cross sections of the parent ions in low pressure discharges in argon, oxygen, and nitrogen, i.e., Ar＋ in Ar, O2＋ in O2 and N2＋ in N2. These ion data are first discussed and then validated from comparisons between the calculated transport coefficients and those measured in the literature. The elastic momentum transfer collision cross sections are determined from a semi-classical approximation for the phase shift calculation based on a 12-6-4 inter-particle potential while ion transport coefficients are determined versus the reduced electric field from Monte Carlo simulations.

关键词： inter-particle interaction potentials phase shift JWKB (Jeffreys WentzelKramers Brillouin) momentum collision cross sections Monte Carlo simulation ion trans-port coefficient

East African Cassava Mosaic Virus and East African Cassava Mosaic Cameroon Virus: Two Species Emerging in Togo

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Agricultural Sciences 2024年第8期15卷 864-876页

作者： Senya Sakina Allado Kossikouma Djodji Adjata Justin Simon Pita Kodjovi Atassé Dansou-Kodjo Assion Sétu Mivedor Koffi Tozo laboratoire de Virologie et de Biotechnologies Vgtales Ecole Suprieure dAgronomie (ESA) Universit de Lom Lom Togo Laboratory of Plant Virology Universit Flix Houphout-Boigny Ple Scientifique et dInnovation Bingerville Cte dIvoire laboratoire de Physiologie et Biotechnologies Vgtales Facult des Sciences Universit de Lom Lom Togo

Cassava mosaic disease (CMD) caused by the whitefly-transmitted Begomoviruses (family Geminiviridae) is a major threat to production of cassava (Manihot esculenta Crantz) in Togo. Survey was conducted in 2020 in the 5 agroecological zones of Togo to assess the status of East African cassava mosaic virus (EACMV), East African cassava mosaic Cameroon virus (EACMCMV) and its distribution. Polymerase chain reaction (PCR) and Sanger sequencing were used for the detection of cassava mosaic Begomoviruses (CMBs) in the sampled leaves. The incidence of EACMV was 47.93% (278/580) and varied between 41.30% (Zone V) and 62.29% (Zone IV) across the agroecological zone but no significant difference was observed. The EACMCMV incidence was 13.67% (38/278) and varied significantly (p ≤ 0.001) through the agroecological zone. Phylogenetic analysis of the viral isolates showed that they are closely related to those from Nigeria, Ghana, and Ivory coast. Nucleotide sequence analysis of CP revealed an overall genetic diversity (π) of around 3.4%. These results showed that EACMV was the predominant virus and that EACMCMV incidence could be more widespread in Togo.

关键词： Begomovirus PCR EACMV EACMCMV Togo Genetic Diversity

Perspective:Chemical Information Encoded in Electron Density

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物理化学学报 2018年第6期34卷 567-580页

作者： CONTRERAS-GARCíA Julia YANG Weitao UPMC Univ Paris 06 CNRSUMR 7616Laboratoire de Chimie Théorique Department of Chemistry Duke University

In this perspective,we review the chemical information encoded in electron density and other ingredients used in semilocal *** information is usually looked at from the functional point of view:the exchange density or the enhancement factor are discussed in terms of the reduced density ***,what parts of a molecule do these 3D functions represent? We look atthese quantities in real space,aiming to understand the electronic structure information they encode and provide an insight from the quantum chemical topology(QCT).Generalized gradient approximations(GGAs) provide information about the presence of chemical interactions,whereas meta-GGAs can differentiate between the different bonding *** merging these two techniques,we show new insight into the failures of semilocal functionals owing to three main errors:fractional charges,fractional spins,and non-covalent *** build on simple *** also analyze the delocalization error in hydrogen chains,showing the ability of QCT to reveal the delocalization error introduced by semilocal ***,we show how the analysis of localization can help understand the fractional spin error in alkali atoms,and how it can be used to correct ***,we show that the poor description of GGAs of isodesmic reactions in alkanes is due to 1,3-interactions.

关键词： DFT Semi-local functional Electron density Quantum chemical topology