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Underground Space 2024年第6期19卷 279-300页

作者： Weiping Luo Dajun Yuan yannick Choy Hing Ng Dalong Jin Ping Lu Teng Wang Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of the Ministry of Education for Urban Underground Engineering Beijing Jiaotong UniversityBeijing 100044China Department of Civil and Environmental Engineering National University of SingaporeSingapore 119077Singapore

Many empirical and analytical methods have been proposed to predict fracturing pressure in cohesive *** of them take into account three to four specific influencing factors and rely on the assumption of a failure *** this study,a novel data-mining approach based on the XGBoost algorithm is investigated for predicting fracture initiation in cohesive *** has the advantage of handling multiple influencing factors simultaneously,without pre-determining a failure mode.A dataset of 416 samples consisting of 14 distinct features was herein collected from past studies,and used for developing a regressor and a classifier model for fracturing pressure prediction and failure mode classification *** results show that the intrinsic characteristics of the soil govern the failure mode while the fracturing pressure is more sensitive to the stress *** XGBoost-based model was also tested against conventional approaches,as well as a similar machine learning algorithm namely random forest ***,several large-scale triaxial fracturing tests and an in-situ case study were carried out to further verify the generalization ability and applicability of the proposed data mining approach,and the results indicate a superior performance of the XGBoost model.

关键词： Fracturing pressure Failure mode Cohesive soil Data-mining Large-scale tests

Structure of nanocrystalline WC-10%Co powder

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中国有色金属学会会刊：英文版 2001年第4期11卷 529-534页

作者：杨志民毛昌辉杜军 Michel Daniel Champion yannick Hagège Serge Htch Martin General Research Institute for Nonferrous Metals Centre d'Etudes de Chimie Métallurgique/CNRS 94407 Vitry-sur-Seine France

Nanostructured WC Co powders obtained by mechanical milling were investigated by combination of X ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) techniques. Rietveld analysis indicates that the experimental XRD patterns cannot be satisfactorily explained with the hexagonal WC structure. HRTEM image analysis shows that in the as milled nanostructured powder, many WC grains contain stacking faults lying on the plane {10·0}. Analysis of phase images show that these defects are nearly periodically ordered along the direction. Based on these observations, a structural model was proposed for the WC grains with ordered stacking faults, which is in fact equivalent to a superstructure of WC with space group Amm2. When this model describing the faulted fraction of WC is introduced together with the normal WC structure (space group P6-m2) into the Rietveld refinement, a much better agreement between the calculated and experimental XRD profiles was obtained. This study allows to obtain the lattice parameters, grain size, microstrain and other structural information on the as milled powders.

关键词： structural properties mechanical milling WC Co

Comparative Study of Two Materials Combining a Standard Building Material with a PCM

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Fluid Dynamics & Materials Processing 2023年第5期19卷 1283-1290页

作者： Marwa El Yassi Ikram El Abbassi Alexandre Pierre yannick Melinge Research Laboratory in Industrial Eco-innovation and Energetics(LR2E) ECAM-EPMICergy-Pontoise95000France Laboratory of Mechanic and Materials of Civil Engineering(L2MGC) University of Cergy-PontoiseCergy-Pontoise95000France Historical Monuments Research Laboratory(LRMH) Champs-sur-Marne77420France

Phase change materials(PCMs)have the ability to store thermal energy and make it available at a later stage to keep indoor temperature within a specific range and achieve better thermal comfort in *** study focuses on the performances of materials obtained by combining a standard building material with a *** particular,two different materials mixed with the same PCM are considered under the same climatic *** related thermal behavior is assessed in the framework of numerical simulations conducted with ANSYS Fluent assuming parameters representative of a city located in *** results show that the addition of PCM to concrete and bricks can improve the thermal inertia of the resulting material.

关键词： Phase change materials building material thermal comfort passive cooling

Microstructural evolution of a recycled aluminum alloy deformed by equal channel angular pressing process

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International Journal of Minerals,Metallurgy and Materials 2012年第11期19卷 1016-1022页

作者： Thabet Makhlouf Atef Rebhi Jean-Philippe Couzinié yannick Champion Nabil Njah Applied Metallurgy Laboratory Faculty of SciencesUniversity of SfaxBP.1171 (3000) Sfax Institut de Chimie et des Matériaux Paris-Est (ICMPE) CNRS 2-8 rue Henri Dunant 94320 Thiais

The microstructural evolution of a recycled aluminum alloy after equal channel angular pressing （ECAP） up to four passes was investigated using X-ray diffxaction （XRD） analysis and transmission electron microscopy （TEM）. Microhardness tests were performed to determine the associated changes in mechanical properties. An ultrafine-grained material has been obtained with a microstructure showing a mixture of highly strained crystallites. A high density of dislocations was achieved as a result of severe plastic deformation （SPD） through the die. Changes in mechanical behavior are also revealed after ECAP due to strain hardening. Thermal analysis and TEM micrographs ob- tained after annealing indicate the succession of the recovery, recrystallization, and grain growth phenomena. Moreover, the energy stored during ECAP may be related to the dislocation density introduced by SPD. We finally emphasize the role played by the precipitates in this alloy.

关键词： aluminum alloys equal channel angular pressing (ECAP) microstructural evolution precipitates

High-density single antibody electrochemical nanoarrays

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Nano Research 2023年第4期16卷 5412-5418页

作者： Khalil Chennit yannick Coffinier Shuo Li Nicolas Clément Agnès Anne Arnaud Chovin Christophe Demaille UniversitéParis Cité CNRSLaboratoire d’Electrochimie MoléculaireParis F-75013France Institute of Electronics Microelectronics and NanotechnologyCNRSUniversity of LilleAvenue PoincaréBP60069Villeneuve d’Ascq 59652France IIS LIMMS/CNRS-IIS UMI2820The University of Tokyo4-6-1 KomabaMeguro-kuTokyo 153-8505Japan

The fabrication and electrochemical interrogation of very high density single-antibody nanoarrays is *** nanodots,15 nm in diameter,arranged in large(cm2)square arrays with a pitch of 200 nm,are used as carriers for primary antibodies(immunoglobulin G(IgG)),further recognized by secondary redox-labeled detection *** scale interrogation of the antibody array by cyclic voltammetry,and nanoscale interrogation of individual nanodots by mediator tethered atomic forcescanning electrochemical microscopy(Mt/AFM-SECM),enable the occupancy of nanodots by single antibody molecules to be *** involving the competitive adsorption of antibodies of different species onto the nanodots evidence the possibility of using single-antibody nanoarrays for digital electrochemical immunoassays.

关键词： single entity electrochemistry electrochemical digital immunoassays atomic force-scanning electrochemical microscopy(AFM-SECM)

Design of New Optogenetic Sinusoidal Probe:Optical and Mechanical Simulation

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Design of New Optogenetic Sinusoidal Probe:Optical and Mecha...

作者： Bouget Maxime yannick Joseph 上海交通大学

学位级别：硕士

经过数年对神经电极微尺寸技术的研究,研究人员期望获得对神经组织更小的侵入性伤害,但是现在微尺寸技术对降低植入‘损伤的性能改善已经触及了机械损伤的极限。最近一些新的电极形状设计（正弦型形状）为减小电极植入的侵入性伤害、提... 详细信息

经过数年对神经电极微尺寸技术的研究,研究人员期望获得对神经组织更小的侵入性伤害,但是现在微尺寸技术对降低植入‘损伤的性能改善已经触及了机械损伤的极限。最近一些新的电极形状设计（正弦型形状）为减小电极植入的侵入性伤害、提高电极记录性能开辟了新的可能性。本文旨在继续探索这种新的电极设计方法,并使其适应最新的神经组织刺激技术:光遗传学技术。本文的目标是找到导光性能良好的柔性形状。首先开展设计可行性研究:形状、材料和制作工艺。在形状和制作工艺层面主要遵循已经发表的有关正弦型电极的结论。这部分还要求必须为光学导向器找到具有良好柔韧性、生物相容性和适宜折射率的芯/包层材料。出于以上考虑,研究中放弃了将Parylene-C/Parylene-N组合作为芯/包层材料的选择。其次,使用两种不同的方法进行光学仿真:光束和光线追踪方法。结果显示了不同的形状参数对光传导的影响。由此,选择了若干组光传导性能较好的形状设计。最后,将在光学仿真软件中找到的各种形状进行力学仿真,得到表征其柔韧性的数据,将其与正弦型电极的侵入性数据进行比较。由于研究中保持了与正弦型电极相同的全局性设计,可以得出新设计电极的侵入性伤害的结论。本文最后得出了一组光学正弦型电极的形状参数、机械和光学特征,理论上可以在改善长期植入电极的植入损伤与记录性能。

关键词：神经探针正弦形光遗传学光学模拟机械模拟

Nonlinear increase,invisibility,and sign inversion of a localized fs-laser-induced refractive index change in crystals and glasses

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Light(Science & Applications) 2020年第1期9卷 1398-1409页

作者： Jerome Lapointe Jean-Philippe Berube yannick ledemi Albert Dupont Vincent Fortin Younes Messaddeq Real Vallee Centre d’Optique Photonique et Laser2375 Rue de la TerrasseUniversite LavalG1V 0A6 QuebecQCCanada

Multiphoton absorption via ultrafast laser focusing is the only technology that allows a three-dimensional structural modification of transparent ***,the magnitude of the refractive index change is rather limited,preventing the technology from being a tool of choice for the manufacture of compact photonic integrated *** propose to address this issue by employing a femtosecond-laser-induced electronic band-gap shift(FLIBGS),which has an exponential impact on the refractive index change for propagating wavelengths approaching the material electronic resonance,as predicted by the Kramers–Kronig *** by theoretical calculations,based on a modified Sellmeier equation,the Tauc law,and waveguide bend loss calculations,we experimentally show that several applications could take advantage of this ***,we demonstrate waveguide bends down to a submillimeter radius,which is of great interest for higher-density integration of fs-laser-written quantum and photonic *** also demonstrate that the refractive index contrast can be switched from negative to positive,allowing direct waveguide inscription in ***,the effect of the FLIBGS can compensate for the fs-laser-induced negative refractive index change,resulting in a zero refractive index change at specific wavelengths,paving the way for new invisibility applications.

关键词： waveguide millimeter refractive

N-alkylamide profiling of Achillea ptarmica and Achillea millefolium extracts by liquid and gas chromatography–mass spectrometry

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Journal of Pharmaceutical Analysis 2017年第1期7卷 34-47页

作者： Lieselotte Veryser Lien Taevernier Evelien Wynendaele yannick Verheust Ann Dumoulin Bart De Spiegeleer Drug Quality and Registration (DruQuaR) group Faculty of Pharmaceutical Sciences Ghent University Ottergemsesteenweg 460 B-9000 Ghent Belgium LIWET Department of Industrial Biological Sciences Ghent University Campus Kortrijk Graaf Karel de Goedelaan 5 B-8500 Kortrijk Belgium

Achillea millefolium and Achillea ptarmica are both plants belonging to the Asteracea family and are traditionally used for their medicinal properties. It has already been shown that some N-alkylamides(NAAs)are responsible for these pharmacological actions. Therefore, in the present study, the NAA content of the two plants was analytically characterised. Different extracts were prepared from the roots, the leaves, the stems and the flowers. The structures of NAAs have been assigned in ethanolic extracts of Achillea millefolium and Achillea ptarmica using high performance liquid chromatography – electrospray ionisation – mass spectrometry(HPLC–ESI–MS) and gas chromatography – electron impact – mass spectrometry(GC–EI–MS). Using both analytical techniques, the structures of 14 and 15 NAAs have been assigned in Achillea ptarmica and Achillea millefolium, respectively. Structures of two new NAAs, previously never observed in Achillea ptarmica,were assigned: deca-2E,6Z,8E-trienoic acid 2-methylbutylamide(homospilanthol) or a related isomeric compound and deca-2E,4E-dienoic acid N-methyl isobutylamide. The structure of homospilanthol or a related isomeric compound was also assigned in Achillea millefolium for the first time.

关键词： N-alkylamides Achillea millefolium Achillea ptarmica HPLC–ESI–MS GC–EI–MS

A Virtual Prototyping Approach for Development of PMSM on Real‑Time Platforms: A Case Study on Temperature Sensitivity

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Automotive Innovation 2022年第3期5卷 285-298页

作者： René Scheer yannick Bergheim Simon Aleff Daniel Heintges Niclas Rahner Rafael Gries Jakob Andert Teaching and Research Area Mechatronics in Mobile Propulsion RWTH Aachen UniversityForckenbeckstr.4Aachen 52074Germany DENSO Automotive Deutschland GmbH Friedrich‑List‑Allee 42Wegberg 41844Germany

This paper presents a comprehensive evaluation of system interactions in a battery electric vehicle caused by temperature sensitivity of permanent magnet synchronous machines(PMSM).An analytical model of a PMSM considering iron losses and thermal impact is implemented on a field programmable gate array suitable for hardware-in-the-loop *** the presented virtual prototyping approach,different machine characteristics defined by the design are used to parameterize the analytical *** investigated temperature effect is understood as an interacting influence between machine character-istics and control,which are investigated in terms of torque generation,voltage utilization and efficiency under closed-loop condition in a vehicle *** particular,using a surface permanent magnet rotor and an interior permanent magnet rotor,the performance of both machine designs is analyzed by varying temperature-adjusted feedforward control strategies on the basis of a driving cycle from a *** comparison shows that the machine design with surface-mounted mag-nets is associated with higher temperature *** this case,the temperature consideration in the feedforward control provides a14%loss reduction in closed-loop vehicle test *** can be summarized that the electromagnetic torque is less sensitive to a temperature variation with increasing *** presented development approach demonstrates the impact of interactions in electric powertrains without the need of real prototypes.

关键词： FPGA PMSM Iron loss FEM Spatial harmonics RT-MIL Virtual prototyping Frontloading Closed-

Isolation and Characterization of Enterococci Bacteriocinic Strains from Tunisian Fish Viscera

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Food and Nutrition Sciences 2013年第6期4卷 701-708页

作者： Migaw Sarra Ghrairi Taoufik le Chevalier Patrick Brillet Benjamin Fleury yannick Hani Khaled Laboratoire Universitaire de Biodiversité et d’Ecologie Microbienne (EA3882) IFR148 ScInBioS Université de Brest Université Européenne de Bretagne IUT de Quimper 6 Rue de l’Université Quimper Cedex France. U12-ES03 Department of Biochemistry Faculty of Medicine Ibn El Jazzar University of Sousse Sousse Tunisia

A collection of lactic acid bacteria isolates from fish viscera was studied and investigated regarding to their functional properties and safety aspects. From these, three isolates GM1, GM2 and GM3 were identified as Enterococcus feacium species using molecular methods. Partial Amplified rDNA Restriction Analysis (partial ARDRA) with restriction enzyme HaeIII separated these isolates into distinctive group which suggest genotypic variability within enterococci strains isolated from fish viscera. The three strains GM1, GM2 and GM3 exhibited antimicrobial activity. Indeed strains have been shown to produce bacteriocins with inhibitory effect against food spoilage bacteria and pathogenic fish including Carnobacterium maltaromaticum. The molecular mass of bacteriocin, as calculated by tricine-SDS-PAGE, was found to be 4.5 kDa. All isolates were tested positive upon PCR amplification of enterocin A structural gene. Investigations of antibiotic resistance show that the isolates were mostly sensitive to several antibiotics (ampicillin, penicillin, tetracycline, gentamycine) and resistance to rifampicin. All isolates grow in esculin azide agar as a selective medium for enumeration of probiotic enterococci. This study suggests that our strains can be employed as probiotic or to improve the safety of food products.

关键词： Bacteriocins Fish Viscera Enterococcus Listeria Carnobacterium Probiotic