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Effect of temperature in the conversion of methanol to olefins （mTO） using an extruded SAPO-34 catalyst

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Frontiers of Chemical Science and Engineering 2018年第2期12卷 226-238页

作者： Ignacio Jorge Castellanos-Beltran Gnouyaro Palla Assima jean-michel Lavoie Universit6 de Sherbrooke Chaire de Recherche Industrielle sur l'Ethanol Cellulosique et les Biocommodities (CRIEC-B) Sherbrooke QC Canada J1L 2Y4

The methanol-to-olefin （mTO） reaction was investigated in a bench-scale, fixed-bed reactor using an extruded catalyst composed of a commercial SAPO-34 （65 weight percentage, wt-%） embedded in an amorphous SiO2 matrix （35 wt-%）. The texture properties, acidity and crystal structure of the pure SAPO-34 and its extruded form （E-SAPO-34） were analyzed and the results indicated that the extrusion step did not affect the properties of the catalyst. Subsequently, E-SAPO-34 was tested in a temperature range between 300 and 500 ~C, using an aqueous methanol mixture （80 wt-% water content） fed at a weight hour space velocity （WHSV） of 1.21 h-1. At 300 ~C, a low conversion was observed combined with the catalyst deactivation, which was ascribed to oligomeriza-tion and condensation reactions. The coke analysis showed the presence of diamandoid hydrocarbons, which are known to be inactive molecules in the mTO process. At higher temperatures, a quasi-steady state was reached during a 6 h reaction where the optimal temperature was identified at 450℃, which incidentally led to the lowest coke deposition combined with the highest H/C ratio. Above 450℃, surges of ethylene and methane were associated to a combination of H-transfer and protolytic cracking reactions. Finally, the present work underscored the convenience of the extrusion technique for testing catalysts at simulated scale-up conditions.

关键词： mTO SAPO-34 temperature extrusion coke light alkanes

On the Liquid-Vapor Phase-Change Interface Conditions for Numerical Simulation of Violent Separated Flows

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Fluid Dynamics & materials Processing 2020年第2期16卷 359-381页

作者： matthieu Ancellin Laurent Brosset jean-michel Ghidaglia UniversitéParis-Saclay ENS Paris-SaclayCNRSCentre BorelliGif-sur-YvetteFrance GTT(Gaztransport&Technigaz) Saint-Rémy-lès-ChevreuseFrance

Numerous models have been proposed in the literature to include phase change into numerical simulations of two-phase *** review paper presents the modeling options that have been taken in order to obtain a model for violent separated flows with application to sloshing wave impacts.A relaxation model based on linear non-equilibrium thermodynamics has been chosen to compute the rate of phase *** integration in the system of partial differential equations is done through a non-conservative advection *** each of these modelling choices,some alternative models from the literature are presented and *** theoretical framework for all phase change model(conservation equations and entropy growth)is also summarized.

关键词： Phase change modeling two-phase flow non-equilibrium thermodynamics compressible flow hyperbolic system of conservation laws

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

Gevrey Class Regularity of a Semigroup Associated with a Nonlinear Korteweg-de Vries Equation

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Chinese Annals of mathematics,Series B 2018年第2期39卷 201-212页

作者： Jixun CHU jean-michel CORON Peipei SHANG Shu-Xia TANG Dedicated to Philippe G. Ciarlet with admiration and friendship on the occasion of his 80th birthda

In this paper, the authors consider the Gevrey class regularity of a semigroup associated with a nonlinear Korteweg-de Vries （KdV for short） equation. By estimating the resolvent of the corresponding linear operator, the authors conclude that the semigroup 3 generated by the linear operator is not analytic but of Gevrey class δ ε （5, ） for t 〉 0,

关键词： Korteweg-de Vries equation Resolvent estimation, Analytic semigroup,Gevrey class

Flocculation and magnetically-assisted sedimentation of size-sorted beidellite platelets mixed with maghemite nanoparticles

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Nano Research 2020年第11期13卷 3001-3011页

作者： Sofia Housni Sébastien Abramson jean-michel Guigner Pierre Levitz Laurent michot Laboratoire de PHysico-chimie des Electrolytes et Nanosystèmes InterfaciauX(PHENIX UmR 8234 Sorbonne Université-CNRS)Sorbonne UniversitéParis75252France Institut de minéralogie de Physique des Matériaux et de Cosmochimie(IMPMC UMR 7590Sorbonne Université-IRD-CNRS-MNHN)Sorbonne UniversitéParis75252France

In this study,the flocculation and the subsequent decantation step of mixed suspensions of 10 nm-sizedγ-Fe_(2)O_(3) magnetic nanoparticles and 500 nm-sized beidellite clay platelets was *** work may find application in the field of water treatment,specifically the flocculation processes with magnetically assisted *** a short description of the preparation and characterization of the raw materials(nanoparticles and clays),the influence of several parameters(pH,concentrations of nanoparticles and clays etc.)on the amount of flocculated materials was examined,which gave information on the concentration ranges allowing a complete flocculation,together with a better understanding on the interactions between nanoparticles and clays responsible for *** optimal conditions for magnetically assisted settling were then determined by comparing for each sample sedimentation velocities under gravity and in the presence of a Nd-Fe-B ***,the complex multiscale structure of the flocs in water was explored,through the measurement of several bulk properties(zeta-potential and volume measurements,laser granulometry),while the organization of the materials at a microscopic scale was investigated by cryo-transmission electron microscopy(cryo-TEm)and small-angle X-ray scattering(SAXS).

关键词： magnetic separation nanoparticles clay flocculation decantation characterization

Induced structural modifications in ZnS nanowires via physical state of catalyst:Highlights of 15R crystal phase

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Nano Research 2022年第1期15卷 377-385页

作者： Sumit Kumar Frederic Fossard Gaelle Amiri jean-michel Chauveau Vincent Sallet Groupe d'Etude de la matiere Condensee(GEmAC) Universite Paris-SaclayCNRS-Universite de Versailles St Quentin en Yvelines45 avenue des Etats-UnisVersailles 78035France Laboratoire d'Etude des microstructures(LEm) CNRS-ONERAUniversite Paris-Saclay29 avenue Division LeclercChatillon 92322France

Peculiar and unique growth mechanisms involved in semiconductor nanowires(NWs)pave the way to the achievement of new crystallographic phases and remarkable material properties,and hence,studying polytypism in semiconductor NWs arouses a strong interest for the next generation of electronic and photonic *** this context,the growth of ZnS nanowires has been investigated,as bulk ZnS compound exhibits numerous unstable polytypes at high temperatures,but their stable occurrence is highly anticipated in a nanowire due to its special quasi-dimensional shape and growth *** this work,the idea is to provide a change in the growth mechanism via the physical state of catalyst droplet(liquid or solid)and hence,study the induced structural modifications in ZnS *** HRTEm images of VLS(via liquid alloyed catalyst)grown ZnS NWs show periodic stacking faults,which is precisely identified as a stacking sequence of cubic or hexagonal individual planes leading to an astonishing 15R crystal *** crystallographic phase is observed for the first time in ***,NWs grown with VSS(via solid catalyst)show crystal polytypes of zinc blende and *** calculate and discuss the role of cohesive energies in the formation of such ZnS ***,we present the selection rules for the crystallization of such 15R structure in NWs and discuss the involved VLS and VSS growth mechanisms leading to the formation of different crystal phases.

关键词： ll-VI semiconductors mOCVD vapor-liquid-solid(VLS) vapor-solid-solid(VSS) TEm analysis polytypism

Human Eosinophil Cell manipulation by Optical Tweezers

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Conducting polymer tattoo electrodes in clinical electro-and magneto-encephalography

Open Journal of Biophysics（生物物理学期刊） 2024年第3期 330页

作者： Pavel Yale jean michel Edoukoua Konin Abadê Ange-Boris N’guessan michel Abaka Kouacou JérémieT.Zoueu

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npj Flexible Electronics 2020年第1期4卷 36-44页

作者： Laura m.Ferrari Usein Ismailov jean-michel Badier Francesco Greco Esma Ismailova Center for microBiorobotics Istituto Italiano di Tecnologia56025 PontederaItaly The BioRobotics Institute Scuola Superiore Sant’Anna56025 PontederaItaly Department of Bioelectronics Ecole Nationale Supérieure des Mines de Saint EtienneCMP-EMSEMOC1354 GardanneFrance Aix marseille Univ INSERMINSInst Neurosci SystMarseilleFrance Institute of Solid State Physics NAWI GrazGraz University of Technology8010 GrazAustria Department of Life Science and medical Bioscience Waseda University169-8480 TokyoJapan

Temporary tattoo electrodes are the most recent development in the field of cutaneous *** have successfully demonstrated their performances in the monitoring of various electrophysiological signals on the *** epidermal electronic devices offer a conformal and imperceptible contact with the wearer while enabling good quality recordings over *** of brain activity in clinical practice face multiple limitations,where such electrodes can provide realistic technological solutions and increase diagnostics *** we present the performance of inkjet-printed conducting polymer tattoo electrodes in clinical electroencephalography and their compatibility with *** working mechanism of these dry sensors is investigated through the modeling of the skin/electrode impedance for better understanding of the biosignals transduction at this ***,a custom-made skin phantom platform demonstrates the feasibility of high-density recordings,which are essential in localizing neuropathological *** evaluations provide valuable input for the successful application of these ultrathin electronic tattoos sensors in multimodal brain monitoring and diagnosis.

关键词： polymer recording conformal

matrix metalloproteinase 13,a new target for therapy in Alzheimer’s disease

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Genes & Diseases 2019年第1期6卷 1-2页

作者： jean-michel Paumier Gopal Thinakaran Departments of Neurobiology Neurologyand PathologyThe University of ChicagoChicagoIL60637USA

Alzheimer’s disease(AD),the most common neurodegenerative disorder,affects millions of people *** a recent publication,Guo-Jun Chen and colleagues highlight the role of matrix metalloproteinase(mmP)13(also called Collagenase 3)in AD pathogenesis through regulating BACE1,1 a rate-limiting enzyme for b-amyloid(Ab)peptide production.2 Proteolytic processing of amyloid precursor protein(APP)by BACE1 and g-secretase generates Ab,which accumulate in brain senile plaques in AD.3 mmPs are a group of enzymes that degrade extracellular matrix and cleave proteins involved in signal transduction.

关键词： Alzheimer’s disease BACE1 eIF4B mmP mmP13 PI3K signaling