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Nano Research 2022年第6期15卷 4873-4879页

作者： Changjun Cheng Xiaofu Zhang michel J.R.Haché Yu Zou Department of Materials Science and Engineering University of TorontoTorontoOntario M5S 3E4Canada State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology and Center for Excellence in Superconducting ElectronicsChinese Academy of Sciences(CAS)Shanghai 200050China

Refractory high-entropy alloys(HEAs)possess many useful properties such as high strength and high-temperature *** far,most studies on refractory HEAs have been limited to a few well-known compositions and on their coarse-grain bulk *** we fabricate nanocrystalline(TiZrHf)_(x)(NbTa)_(1−x)HEA thin films with a large range of compositions(x=0.07–0.90)by the direct current(DC)magnetron co-sputtering technique and measure their mechanical properties using the nanoindentation *** the as-deposited HEA thin films show a solid-solution body-centered cubic(bcc)*** the compositional ratio(x)increases,the elastic modulus decreases from 153 to 123 GPa,following the trend of the rule of *** x increases,the hardness first decreases from 6.5 GPa(x=0.07)to the lowest value(4.6 GPa,x=0.48)and then increases to the highest value(7.1 GPa,x=0.90),showing a concave *** change in hardness might be attributed to the combinational influence caused by the atomic size and modulus effects,as well as the texture *** authors also propose a few open questions for future studies on this and related HEA systems.

关键词： high-entropy alloys nanocrystalline alloys refractory metals thin films magnetron co-sputtering nanoindentation

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

ALGEBRAIC INDEPENDENCE OF CERTAIN NUMBERS RELATED TO LIOUVILLE NUMBERS

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Science China Mathematics 1990年第3期33卷 257-268页

作者： michel WALDSCHMIDT 朱尧辰 Institut Institute of Applied Mathematics Academia Sinica Beijing 100080 PRC

In this paper, we develop an algebraic independence method originated from a work of Mordoukhay-Boltovskoy, which allows us to establish the algebraic independence of certain numbers connected with Liouville numbers. This method depends either on elementary results of the Kummer theory or on transcendence measures for certain classes of numbers.

关键词： Liouville number Kummer theory transcendence measure algebraic independence.

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

Statistical analysis of the ion density measured by the satellite DEMETER in relation with the seismic activity

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Earthquake Science 2011年第6期24卷 513-521页

作者： michel Parrot Laboratoire de Physique et Chimie de l'Environnement et de l'Espace Universite d'OrléansCNRS3A Avenue de la Recherche Scientifique45071 Orleans cedex 2France

This paper is related to study of the ion density recorded by the low altitude satellite DEMETER. It will present ionospheric perturbations observed during large seismic events. As the ionosphere is highly variable, the paper will show a statistical analysis performed on the plasma parameters during night time. An algorithm has been implemented to detect crests and troughs in the data before world-wide earthquakes. The earthquakes have been classified depending on their magnitude, depth, and location （land, below the sea, close to a coast）. Due to the orbit, DEMETER returns above the same area every day （once during day time, once during night time） but not at the same distance of a given epicenter. Then, for each earthquake, data have been checked until 15 days before the shock when the distance between the trace of the orbit and the epicenter is less than 1 500 km. The results of the statistical analysis are presented as functions of various parameters. A comparison is done with two other databases where, on one hand, the location of the epicenters has been randomly modified, and on the other hand, the longitude of the epicenters has been shifted. Results show that the number and the intensity of the ionospheric perturbations are larger prior to earthquakes than prior to random events, and that the perturbations increase with the magnitude.

关键词： ionosphere earthquake satellite statistic

Numerical simulations of water flow and contaminants transport near mining wastes disposed in a fractured rock mass

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International Journal of Mining Science and Technology 2015年第1期25卷 37-45页

作者： Ben Abdelghani Farouk Aubertin michel Simon Richard Therrien René Department of Civil Engineering Institut Supérieur de la Construction et de l’Urbanisme Research Institute on Mines and the Environment (RIME) Polytechnique Montreal Department of Geology and Geological Engineering University Laval

A numerical tool, called Hydro-Geosphere, was used to simulate unsaturated water flow and contaminants migration around an open pit filled with mining wastes. Numerical simulations had been carried out to assess the influence of various factors on water flow and solute transport in and around the surface openings including recharge, properties of the waste material and presence of fractures in the surrounding rock mass. The effect of the regional hydraulic gradient was also investigated. The analyses were conducted by simulating various 2D cases using experimentally obtained material properties and controlled boundary conditions. The effects of the hydrogeological properties of the filling material(i.e., water retention curve and hydraulic conductivity function), fracture network characteristics and conductivity of the joints were assessed. The results illustrate that fractures control water flow and contaminants transport around the waste disposal area. A fracture network can desaturate the system and improve the regional gradient effect.

关键词： Hydro-GeosphereNumerical modellingUnsaturated water flowContaminants transportTailingsWaste rocks

Endoscopic palliation of malignant biliary stricture

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World Journal of Gastrointestinal Oncology 2016年第3期8卷 240-247页

作者： Sanjay M Salgado Monica Gaidhane michel Kahaleh Division of Gastroenterology and Hepatology Weill Cornell Medical College

Malignant biliary strictures often present late after the window for curative resection has elapsed. In such patients, the goal of therapy is typically focused on palliation. While historically, palliative measures were performed surgically, the advent of endoscopic intervention offers minimally invasive options to provide relief of symptoms, improve quality of life, and in some cases, increase survival of these patients. Some of these therapies, such as endoscopic biliary decompression, have become mainstays of treatment for decades, whereas newer modalities, including radiofrequency ablation, and photodynamic therapy offer additional options for patients with incurable biliary malignancies.

关键词： Biliary strictures Malignant Endoscopic retrograde cholangiopancreatography Photodynamic therapy Endoscopy Palliation Endoscopic ultrasound Radiofrequency ablation

Prevalence of iron deficiency in patients aged 75 years or older with heart failure

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Journal of Geriatric Cardiology 2018年第11期15卷 682-686页

作者： Paul Mini Bonnefoy Marc Subtil Fabien michel Chuzeville Geriatric Cardiology Department Edouard Herriot Hospital Hospices Civils de Lyon Lyon France Geriatric Department Lyon South Hospital Hospices Civils de Lyon Lyon France Biostatistics Health Department University Claude Bernard Lyon 1 Hospices Civils de Lyon Lyon France

Background The latest studies presented at the American Heart Association (AHA) meeting on heart failure and the update of the European Cardiology Society’s (ECS) recommendations on heart failure in 2016 recommend intravenous iron supplementation in patients with heart failure, reduced ejection fraction and iron deficiency for improves walking performance and quality of life, and reduces morbidity. In the present study, we investigated the prevalence of iron deficiency in heart failure patients aged 75 years or older, as there is currently no data on these patients. Methods We performed an observational study on hospitalized patients in Geriatric Cardiology Department. Among the 462 patients hospitalized during eight months, 176 were eligible for inclusion;22 patients was significant interference with an inflammatory syndrome (high ferritin with high C-reactive protein), and for 13 patients iron-related data were not available. For each patient included, a complete iron assessment and type of heart failure was available. Results A total of 141 patients were included, the mean age was 88 years (range: 75–101), and there were 52 (36.9%) of patients with reduced ejection fraction (EF), 37 (26.2%) with mid-range EF, and 52 (36.9%) with preserved EF. Irrespective of heart failure type, 73.8% had iron deficiency (95% CI: 65.7%–80.8%);this was found in 57.7%(95% CI: 43.2%–71.3%) of those with reduced EF, 78.4%(95% CI: 61.8%–90.2%) of those with mid-range EF, and 86.5%(95% CI: 74.2%–94.4%) of those with preserved EF (P = 0.003). Conclusion The prevalence of iron deficiency was very high in very elderly patients with heart failure, especially those with HF with mid-range EF or HF with preserved EF.

关键词： Heart failure Iron deficiency Very elderly patient

Influence of working gas pressure on the performance of W/Si multilayers

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Chinese Physics C 2012年第9期36卷 909-914页

作者：王芳芳朱京涛钟奇王占山 Philippe Jonnard Karine Le Guen Jean-michel André michel Fialin Institute of Precision Optical Engineering Department of PhysicsTongji University Laboratoire Chimie Physique-Matière Rayonnement UPMC Univ Paris 06CNRS UMR 761411 rue Pierre et Marie CurieF-75231 Paris Cedex 05France Centre CAMPARIS CNRS UMR 7154campus Jussieu4 place JussieuF-75254 Paris Cedex 05France

The effect of Ar pressure on the performance of W/Si multilayers is investigated. W/Si multilayers were deposited by a high vacuum DC magnetron sputtering system. The Ar pressure was changed from 1.0 to 5.0 mTorr with an interval of 1.0 mTorr during the deposition process. Electron probe microanalysis and Rutherford backscattering are performed to determine the Ar content incorporated within these multilayers. The results demonstrate that less Ar is incorporated within the sample when more Ar is used in the plasma, which could be explained by the increase of the collision probability and the decrease in the kinetic energy of Ar ions arriving at the substrate when more Ar exists. The grazing incident X-ray reflectivity （GIXR） at 0.154 nm is used to determine the structural parameters of the layers. The results show that the structures of these multilayers prepared at different Ar pressure are very similar and that the interface roughness increases quickly when the Ar pressure is higher than 3.0 mTorr. The measurements of the extreme ultraviolet （EUV） reflectivity indicate that the reflectivity decreases when Ar pressure increases. The fitting results of GIXR and EUV refiectivity curves indicate that with an increase of Ar pressure, the density and decrement of the refractive index are increased for W and decreased for Si, which is mainly due to （1） the decrease in Ar content incorporated within these multilayers which affects their performance and （2） the increase of collision probability for sputtered W and Si, the decrease of their average kinetic energy arriving at the substrate, and thus the loosing of their layers.

关键词： multilayer deposition working pressure EPMA RBS reflectivity

Attractors for a Three-Dimensional Thermo-Mechanical Model of Shape Memory Alloys

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Chinese Annals of Mathematics,Series B 2006年第6期27卷 683-700页

作者： Pierluigi COLLI michel FRMOND Elisabetta ROCCA Ken SHIRAKAWA Dipartimento di Matematica "F. Casorati" Università degli Studi di Paviavia Ferrata 127100 PaviaItaly. Laboratoire Central des Ponts et Chaussées 58 Boulevard Lefebvre75732 Paris Cedex 15France. Dipartimento di Matematica "F. Enriques" Università degli Studi di Milanovia Saldini 5020133 MilanoItaly. Department of Applied Mathematics Faculty of Engineering Kobe University 1-1 RokkodaiNadaKobe 657-8501Japan.

In this note, we consider a Fremond model of shape memory alloys. Let us imagine a piece of a shape memory alloy which is fixed on one part of its boundary, and assume that forcing terms, e.g., heat sources and external stress on the remaining part of its boundary, converge to some time-independent functions, in appropriate senses, as time goes to infinity. Under the above assumption, we shall discuss the asymptotic stability for the dynamical system from the viewpoint of the global attractor. More precisely, we generalize the paper dealing with the one-dimensional case. First, we show the existence of the global attractor for the limiting autonomous dynamical system; then we characterize the asymptotic stability for the non-autonomous case by the limiting global attractor.

关键词： Shape memory Thermomechanical model Parabolic system of partial differential equations Global attractor