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Journal of materials Science & Technology 2021年第5期64卷 1-9页

作者： Rajendra Kurapati Vincent maurice Antoine Seyeux Lorena H.Klein Dimitri mercier Gregory Chauveau Catherine Grees-Besset Loic Berthod Philippe marcus PSL Research University CNRS-Chimie ParisTechInstitut De Recherche De Chimie ParisPhysical Chemistry of Surfaces Group11 Rue Pierre Et Marie Curie75005 ParisFrance CILAS mARSEILLE 600 Avenue De La Roche FourcadePole ALPHA Sud-Saint Mitre13400 AubagneFrance CNES Sous-direction Assurance QualitéService TechnologiesMatériaux Et Procédés18 AvenueÉdouard Belin31401 ToulouseFrance

Protection of silver mirror stacks from environmental degradation before launching is crucial for space ***,we report a comparative study of the advanced protection of silver mirror stacks for space telescopes provided by SiO_(2)and Al_(2)O_(3)coatings in conditions of accelerated aging by *** model silver stack samples were deposited by cathodic magnetron sputtering on a reference silica substrate for optical applications and a surface-pretreated SiC *** aging was per-formed in dry and more severe wet *** micrographic observations,surface and interface analysis by Time-of Flight Secondary Ion mass Spectrometry(ToF-SImS)and reflectivity measurements were combined to comparatively study the effects of *** results show a lower kinetics of degradation by accelerated aging of the stacks protected by the alumina coating in comparable test conditions.

关键词： mirror layers Protection Layers Silver Atmospheric corrosion Accelerated aging Surface analysis Space applications

Impact of train speed on the mechanical behaviours of track-bed materials

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Journal of Rock mechanics and Geotechnical Engineering 2017年第5期9卷 818-829页

作者： Francisco Lamas-Lopez Yu-Jun Cui Nicolas Calon Sofia Costa D’Aguiar Tongwei Zhang Laboratoire Navier/CERmES Ecole des Ponts ParisTech Marne-la-Vallée 77455 France Département Ligne Voie et Environnement SNCF-Engineering La Plaine St. Denis 93574 France Division Auscultation Modélisation & Mesures SNCF-Research & Development Paris 75012 France

For the 30,000 km long French conventional railway lines(94% of the whole network),the train speed is currently limited to 220 km/h,whilst the speed is 320 km/h for the 1800 km long high-speed ***,there is a growing need to improve the services by increasing the speed limit for the conventional *** paper aims at studying the influence of train speed on the mechanical behaviours of track-bed materials based on field monitoring *** is put on the behaviours of interlayer and subgrade *** selected experimental site is located in Vierzon,*** sensors including accelerometers and soil pressure gauges were installed at different *** vertical strains of different layers can be obtained by integrating the records of accelerometers installed at different trackbed *** experimentation was carried out using an intercity test train running at different speeds from 60 km/h to 200 km/*** test train was composed of a locomotive(22.5 mg/axle) and 7 'Corail'coaches(10.5 mg/axle).It was observed that when the train speed was raised,the loadings transmitted to the track-bed ***,the response of the track-bed materials was amplified by the speed rise at different depths:the vertical dynamic stress was increased by about 10% when the train speed was raised from 60 km/h to 200 km/h for the locomotive loading,and the vertical strains doubled their quasistatic values in the shallow ***,the stressestrain paths were estimated using the vertical stress and strain for each train *** loading paths allowed the resilient modulus mrto be *** was found that the resilient modulus(m_r) was decreased by about 10% when the train speed was increased from 100 km/h to 200 km/***,the damping ratio(D_r) kept stable in the range of speeds explored.

关键词： Field experimentation Conventional track-bed materials Train speed upgrade mechanical behaviours Reversible modulus Damping ratio

Fabricating a reactive surface on the fibroin film by a room-temperature plasma jet array for biomolecule immobilization

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Chinese Physics B 2012年第10期21卷 313-320页

作者：陈光良郑旭吕国华张朝霞 Sylvain massey Wilson Smith michael Tatoulian 杨思泽 Key Laboratory of Advanced Textile materials and manufacturing Technology of ministry of Education and Engineering Research Center for Eco-Dyeing&Finishing of TextilesZhejiang Sci-Tech University Key Laboratory of Soft matter Physics Institute of PhysicsChinese Academy of Sciences cole Nationale Suprieure de Chimie de Paris-Chimie paristech Laboratoire de G'enie des Proc'ed'es Plasmas et Traitements de SurfacesUniversit'e Pierre et Marie CurieParis 75005France

A simple dielectric barrier discharge（DBD） jet array was designed with a liquid electrode and helium *** characteristics of the jet array discharge and the preliminary polymerization with acrylic acid（AA） monomer were *** plasma reactor can produce a cold jet array with a gas temperature lower than 315 K,using an applied discharge power between 6 W and 30 W（V dis × I dis）.A silk fibroin film（SFF） was modified using the jet array and AA monomer,and the treated SFF samples were characterized by atomic force microscopy（AFm）,scanning electron microscopy（SEm）,Fourier transform infrared spectroscopy（FTIR）,and contact angle（CA）.The deposition rate of the poly acrylic acid（PAA） was able to reach 300 nm/min,and the surface roughness and energy increased with the AA flow *** FTIR results indicate that the modified SFF had more carboxyl groups（-COOH） than the original *** latter characteristic allowed the modified SFF to immobilize more quantities of antimicrobial peptide（AP,LL-37） which inhibited the Escherichia coli（***） effectively.

关键词： plasma jet array polymerizing modification fibroin film antimicrobial property

Friction and Wear Behavior of Ti-6Al-7Nb Biomaterial Alloy

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Journal of Biomaterials and Nanobiotechnology 2013年第4期4卷 374-384页

作者： mamoun Fellah Omar Assala mohamed Labaiz Leila Dekhil Alain Iost Surface Engineering and Tribology Team Laboratory of Metallurgy and Engineering MaterialsBADJI Mokhtar-Annaba UniversityAnnabaAlgeria Laboratory of Formability and metallic materials BADJI Mokhtar-Annaba UniversityAnnabaAlgeria Laboratory of metallurgy ARTS ET METIERS ParisTechLilleFrance

Titanium has been increasingly applied to biomedical application because of its improved mechanical characteristics, corrosion resistance and biocompatibility. However their application remains limited, due to the low strength and poor wear resistance of unalloyed titanium. The purpose of this study is to evaluate the friction and wear behavior of high-strength titanium alloys: Ti-6Al-7Nb used in femoral stem (total hip prosthesis). The oscillating friction and wear tests have been carried out in ambient air with oscillating tribotester in accord with standards ISO 7148, ASTm G99-95a, ASTm G 133-95 under different conditions of normal applied load (3, 6 and 10 N) and sliding speed (1, 15 and 25 mm.s-1), and as a counter pair we used the ball of 100C 6, 10 mm of diameter. The surface morphology of the titanium alloys has been characterized by SEm, EDAX, micro hardness, roughness analysis measurements. The behavior observed for both samples suggests that the wear and friction mechanism during the test is the same for Ti alloys, and to increase resistance to wear and friction of biomedical titanium alloys used in total hip prosthesis (femoral stems) the surface coating and treatment are required.

关键词： Tribological Behavior Friction and Wear Tests Biomaterial Total Hip Prosthesis Ti-6Al-7Nb

Volume and fat infiltration of spino-pelvic musculature in adults with spinal deformity

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World Journal of Orthopedics 2015年第9期6卷 727-737页

作者： Bertrand moal Nicolas Bronsard José G Raya Jean marc Vital Frank Schwab Wafa Skalli Virginie Lafage Spine Division Hospital for Joint DiseasesNew-York University University Langone Medical Center Nice University Hospital Center Orthopedic and Traumatologic Surgery DepartmentH?pital Saint Roch Center for Biomedical Imaging Department of RadiologyNew York University Langone Medical Center University Hospital of Bordeaux Spinal UnitDepartement of Orthopaedic Surgery Laboratory of Biomechanics Arts et Métiers ParisTech

AIm: To investigate fat infiltration and volume of spino-pelvic muscles in adults spinal deformity(ASD) with magnetic resonance imaging(mRI) and 3D ***: Nineteen female ASD patients(mean age 60 ± 13) were included prospectively and consecutively and had T1-weighted Turbo Spin Echo sequence mRIs with Dixon method from the proximal tibia up to T12 vertebra. The Dixon method permitted to evaluate the proportion of fat inside each muscle(fat-water ratio). In order to investigate the accuracy of the Dixon method for estimating fat vs water, the same mRI acquisition was performed on phantoms of four vials composed of different proportion of fat vs water. With muscl'X software, 3D reconstructions of 17 muscles or group of muscles were obtained identifying the muscle's contour on a limited number of axial images [Deformation of parametric specific objects(DPSO) method]. musclar volume(Vmuscle), infiltrated fat volume(Vfat) and percentage of fat infiltration [Pfat, calculated as follow: Pfat = 100 ×(Vfat/Vmuscle)] were characterized by extensor or flexor function respectively for the spine, hip and knee and theirs relationship with demographic data were investigated. RESULTS: Phantom acquisition demonstrated a non linear relation between Dixon fat-water ratio and the real fat-water ratio. In order to correct the Dixon fatwater ratio, the non linear relation was approximated with a polynomial function of degree three using the phantom acquisition. On average, Pfat was 13.3% ± 5.3%. muscles from the spinal extensor group had a Pfat significantly greater than the other muscles groups, and the largest variability(Pfat = 31.9% ± 13.8%, P muscles from the hip extensor group ranked 2nd in terms of Pfat(14% ± 8%), and were significantly greater than those of the knee extensor(P = 0.030). muscles from the knee extensor group demonstrated the least Pfat(12% ± 8%). They were also the only group with a significant correlation between Vmuscle and Pfat(r =-0.

关键词： Spino-pelvic musculature Adults with spinal deformity muscular degeneration muscular volume Fat infiltration Dixon method

Effect of Replacing Vanadium by Niobium and Iron on the Tribological Behavior of HIPed Titanium Alloys

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Acta metallurgica Sinica(English Letters) 2017年第11期30卷 1089-1099页

作者： mamoun Fellah Linda Aissani mohammed Abdul Samad Alain Iosts Touhami mohamed Zine Alex montagnes Corinne Nouveau mechanical Engineering Department ABBES Laghrour University P.O. 1252 40004 Khenchela Algeria Tribology Materials Surface and Interfaces GroupLaboratory of Foundry BADJI Mokhtar University BO 12CP 23000 Annaba Algeria Physics Department ABBES Laghrour University P.O.1252 40004 Khenchela Algeria mechanical Engineering Department KFUPM Box 1180Dhahran 31261 Kingdom of Saudi Arabia Laboratory of mechanics Surfaces and Processing materials ARTS ET METIERS ParisTech Boulevard Louis XIV 859046 Lille Cedex France La.Bo.ma.P ENSAM Rue Porte de Paris 71250 ClunyFrance

This study aims to examine the effect of replacing vanadium by niobium and iron on the tribological behavior of hot-isostatic-pressed titanium alloy （Ti-6Al-4V） biomaterial, using a ball-on-disk-type oscillating tribometer, under wet conditions using physiological solution in accordance with the ISO7148 standards. The tests were carried out under a normal load of 6 N, with an AISI 52100 grade steel ball as a counter face. The morphological changes and structural evolution of the nanoparticle powders using different milling times （2, 6, 12 and 18 h） were studied. The morphological characterization indicated that the particle and crystallite size continuously decrease with increasing milling time to reach the lowest value of 4 nm at 18-h milling. The friction coefficient and wear rate were lower in the samples milled at 18 h （0.226, 0.297 and 0.423; and 0.66 × 10-2, 0.87 × 10-2 and 1.51 × 10-2 μm3 N-1 i, tm-1） for Ti-6Al-4Fe, Ti-6A1-7Nb and Ti-6Al-4V, respectively. This improvement in friction and wear resistance is attributed to the grain refinement at 18-h milling. The Ti-6Al-4Fe samples showed good tribological performance for all milling times.

关键词： Tribological behavior Titanium alloys Wear testing Nanotribology milling time Hot isostatic pressing(HIPing)

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曲率与褶皱

曲率与褶皱

Passivating buried interface with multifunctional novel ionic liquid containing simultaneously fluorinated anion and cation yielding stable perovskite solar cells over 23% efficiency

2018年全国固体力学学术会议

作者：徐凡杨易凡戴晖辉 m.Potier-Ferry 复旦大学航空航天系力学与工程仿真研究所香港城市大学数学系 University of Lorraine CNRSArts et Métiers ParisTech

轻轻挤压桌上一张A4纸时,整个纸张在桌面上隆起形成波浪状;撸起袖子或眨眼睛时,则会在袖子或眼睑上出现各种复杂褶皱。这类现象都可归纳为软薄膜在硬基底上面内受压产生的非线性失稳变形。然而,撸起的袖子所呈现出的失稳模态远比平面纸... 详细信息

轻轻挤压桌上一张A4纸时,整个纸张在桌面上隆起形成波浪状;撸起袖子或眨眼睛时,则会在袖子或眼睑上出现各种复杂褶皱。这类现象都可归纳为软薄膜在硬基底上面内受压产生的非线性失稳变形。然而,撸起的袖子所呈现出的失稳模态远比平面纸张(零曲率)屈曲时复杂,其本质原因在于曲率的作用。为探索曲率与褶皱的关系,我们通过实验、计算和理论分析轴向受压的柱面软壳在硬基底上的非线性变形演化全景。我们发现一个新颖的后屈曲响应,即光滑(smooth)-褶皱(wrinkle)-凸脊(ridge)-松垂(sagging)的多重分岔失稳行为。柱壳在临界载荷下首先失稳形成正弦形轴对称褶皱。进一步压缩下,周期性的褶皱将产出二次分岔,向局部化的凸脊形模态转变。当载荷达到第三个分岔点时,凸脊的挠度达到极限,随后由于对称性破缺倒向一边而发生松垂偏转。我们发现在褶皱-凸脊和凸脊-松垂转变的阶段分别存在迟滞现象(hysteresis),即存在maxwell应变。另外,这种多重分岔失稳行为具有普适性,主要依赖于几何非线性而非材料非线性。研究结果为软薄膜表面形貌的力学调控与设计提供了新的思路。

关键词：薄膜失稳后屈曲分岔对称性破缺形貌演化大变形

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Journal of Energy Chemistry 2022年第6期31卷 659-666,I0018页

作者： Deyu Gao Liqun Yang Xiaohui ma Xueni Shang Chen Wang mengjia Li Xinmeng Zhuang Boxue Zhang Hongwei Song Jiangzhao Chen Cong Chen School of material Science and Engineering State Key Laboratory of Reliability and Intelligence of Electrical EquipmentHebei University of TechnologyTianjin 300130China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012JilinChina Chimie paristech PSL Research UniversityCNRSInstitut de Recherche de Chimie Paris(IRCP)UMR824711 rue P.et M.CurieF-75005 ParisFrance Key Laboratory of Optoelectronic Technology&Systems(ministry of Education) College of Optoelectronic EngineeringChongqing UniversityChongqing 400044China

Interfacial defects and energy barrier would result in serious interfacial non-radiative recombination *** addition,the quality of perovskite films is highly dependent on deposition ***,there is an urgent desire to develop multifunctional interface modulators to manage the interface between electron transport layer and perovskite ***,we report a multifunctional buried interface modulation strategy that 4-fluoro-phenylammonium tetrafluoroborate (FBABF_(4)) consisting of simultaneously fluorinated anion and cation is inserted between SnO_(2)layer and perovskite *** is uncovered by time-of-flight secondary ion mass spectroscopy that the anion and cation in modifier are mainly located at this interface,which is put down to coordination bond of the fluorine atom on BF_(4)^(-) with SnO_(2),and the hydrogen bond of the fluorine atom on FBA^(+) with *** suggests that simultaneous fluorination of anion and cation in the ionic liquid molecule is of crucial importance to ameliorate interfacial contact through chemical *** interface modification approach enables the realization of interfacial defect passivation,interfacial energy band alignment modulation,and perovskite crystallization manipulation,which are translated into enhanced efficiency and stability as well as significantly suppressed *** multiple functions of FBABF_(4) endow the modified solar cells excellent photovoltaic performance with an efficiency exceeding 23%along with appealing long-term *** work highlights the critical role of fluorination strategy in engineering multifunctional organic salt modulators for improving interfacial contact.

关键词： Perovskite solar cells Interface engineering Buried interface Ionic liquid multifunctional

The deformation and permeability of Yanji mudstone under cyclic loading and unloading

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Journal of mountain Science 2019年第12期16卷 2907-2919页

作者： ZENG Zhi-xiong KONG Ling-wei WANG Jun-tao State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Ecole des Ponts paristech U.R.Navier/CERMES6 et 8 av.Blaise PascalCite DescartesChamps-sur-Mame77455 Mame-la-Vallee cedex 2France

During the constructions of motorways and high-speed railway lines in the Yanji Basin,large amounts of excess mudstones due to the enormous tunnel excavations and slope cuts would be deposited as *** the deformation and permeability of Yanji mudstone became important for the design,construction and operation of the *** paper presents an experimental study on the deformation and permeability of Yanji mudstone by carrying out a series of oedometer tests with loading/unloading *** results show that the sample with a lower initial water content exhibited greater swelling deformation after inundation,a lower yield stress,greater deformation and a higher hydraulic conductivity during the loading/unloading *** the number of loading/unloading cycles increased,the yield stress and accumulated plastic deformation increased,while the compression index,rebound index and hydraulic conductivity *** samples became stiffer and their hydromechanical behaviour tended to be stable after three *** compression curves could be divided into pre-yield and post-yield *** post-yield zones of compression curves and the rebound curves could be normalized into a unique line,and the pre-yield zones of the compression curves could be described as *** equations were developed to predict mudstone deformation under cyclic loading and ***,an empirical relationship between the hydraulic conductivity and void ratio was also *** ability of the proposed methods was verified by the overall good agreement between the experimental results and predicted values.

关键词： mudstone Swelling Cyclic loading and unloading Deformation Permeability