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Study of mg-Al-Ca magnesium alloy ameliorated with designed Al8mr4Gd phase

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Journal of magnesium and Alloys 2020年第4期8卷 1084-1089页

作者： Chaosheng ma Wenbo Yu Xufeng Pi Antoine Guitton School of mechanical and Electronic Control Engineering Beijing JiaoTong UniversityBeijingChina Universite de Lorraine-CNRS-arts et metiers paristech-LEm3 F-57000 MetzFrance Laboratory of Excellence on Design of Alloy metals for low-niAss Structures(DAmAS) Universite de LorraineF-57073 MetzFrance

To investigate the effect of Alsmn4Gd phase on microstructural and mechanical properties of mg-Al-Ca magnesium alloy,two mg-2.5AbCa and mg-2.5Al2Ca-0.1 Al8mn4Gd alloys were designed and compared in this *** results show that a small amount of Gd can significantly refine a-mg grains and change the morphology of AUCa ***,the formed Al8mn4Gd phase could serve as a heterogeneous nucleation site for the a-mg grains and AbCa ***,the introduction of Gd not only optimized the mechanical properties of mg-Al-Ca alloy,but also facilitated the thermal deformation(such as hot rolling).

关键词： mg-Al-Ca alloy AlgNlruGd phase microstructure and mechanical properties Hot rolling.

含缺陷压铸AlSi9Cu3合金疲劳寿命的计算

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稀有金属 2018年第8期42卷 791-798页

作者：陈颖张峥 Franck morel 北京航空航天大学材料科学与工程学院北京100191 arts et metiers paristech Laboratoire LAmPA Angers France 49035

研究压铸铝合金AlSi9Cu3基体中铸造缺陷和疲劳寿命的关系有望实现铝合金疲劳寿命的预测，具有较大的工程实用价值。采用Paris公式可以对含缺陷铝合金的疲劳寿命进行计算。然而在现有报道中，缺陷类型对合金疲劳寿命的影响被忽略，导致... 详细信息

研究压铸铝合金AlSi9Cu3基体中铸造缺陷和疲劳寿命的关系有望实现铝合金疲劳寿命的预测，具有较大的工程实用价值。采用Paris公式可以对含缺陷铝合金的疲劳寿命进行计算。然而在现有报道中，缺陷类型对合金疲劳寿命的影响被忽略，导致计算的准确性降低。本文在对含缺陷压铸AlSi9Cu3铝合金试样的疲劳寿命测试的基础上，通过引入缺陷类型的几何因子对Paris公式进行修正，提高了其计算精度。首先，通过对试样进行疲劳实验和断口分析，明确了合金中主要包括3种裂纹：穿透裂纹、表面裂纹和角裂纹。其次，采用公式计算得到穿透裂纹、表面裂纹和角裂纹的平均几何因子分别为1．421，0．814和0．947，其中穿透裂纹对疲劳寿命的影响最大。在此基础上，采用Paris-Erdogan公式对铝合金的疲劳寿命进行了计算，计算疲劳寿命与实验疲劳寿命结果相吻合，计算误差在一倍以内，证实了假设的合理性和计算的可行性。该计算可以在实际应用中为含缺陷铝合金寿命的预测提供重要的理论基础和实际参考。

关键词：压铸铝合金几何因子 Paris公式疲劳寿命计算

The Role of a Novel Discrete-Time mRAC Based motion Cueing on Loss of Control at a Hexapod Driving Simulator

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Intelligent Control and Automation 2015年第1期6卷 84-102页

作者： B. Aykent D. Paillot F. merienne C. Guillet A. Kemeny CNRS Le2i arts et metiers paristech Chalon sur Saone France Technical Centre for Simulation Renault Guyancourt France

The objective of this paper is to present the advantages of model reference adaptive control (mRAC) motion cueing algorithm against the classical motion cueing algorithm in terms of biomechanical reactions of the participants during the critical maneuvers like chicane in driving simulator real-time. This study proposes a method and an experimental validation to analyze the vestibular and neuromuscular dynamics responses of the drivers with respect to the type of the control used at the hexapod driving simulator. For each situation, the EmG (electromyography) data were registered from arm muscles of the drivers (flexor carpi radialis, brachioradialis). In addition, the roll velocity perception thresholds (RVT) and roll velocities (RV) were computed from the real-time vestibular level measurements from the drivers via a motion-tracking sensor. In order to process the data of the EmG and RVT, Pearson’s correlation and a two-way ANOVA with a significance level of 0.05 were assigned. moreover, the relationships of arm muscle power and roll velocity with vehicle CG (center of gravity) lateral displacement were analyzed in order to assess the agility/alertness level of the drivers as well as the vehicle loss of control characteristics with a confidence interval of 95%. The results showed that the mRAC algorithm avoided the loss of adhesion, loss of control (LOA, LOC) more reasonably compared to the classical motion cueing algorithm. According to our findings, the LOA avoidance decreased the neuromuscular-visual cues level conflict with mRAC algorithm. It also revealed that the neuromuscular-vehicle dynamics conflict has influence on visuo-vestibular conflict;however, the visuo-vestibular cue conflict does not influence the neuromuscular-vehicle dynamics interactions.

关键词： Driving Simulator EmG Analysis model Reference Adaptive Control Discrete-Time Control Loss of Control Head Dynamics

Persistent X-ray-activated phosphors:mechanisms and applications

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Light(Science & Applications) 2022年第6期11卷 1008-1010页

作者： Cyrille Richard Bruno Viana UniversitéParis Cité CNRSINSERMUTCBSUnitéde Technologies Chimiques et Biologiques pour la SantéFacultéde Pharmacie75006 ParisFrance IRCP CNRS UMR8247PSL UniversityChimie ParisTech11 Rue P&M Curie75005 ParisFrance

Trivalent lanthanides in wide bandgap fluoride or phosphate hosts can present persistent luminescence between 200 nm and 1.7 μm after charging by *** are reviewed and applications envisioned.

关键词： lanthanide fluoride luminescence

Tonal Noise Prediction of an Automotive Engine Cooling Fan： Comparison between Analytical models and Acoustic Analogy Results

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Journal of mechanics Engineering and Automation 2012年第7期2卷 455-463页

作者： Elias Tannoury Sofiane Khelladi Bruno Demory manuel Henner Farid Bakir Valeo Thermal Systems La Verriere 78321 France Laboratoire de Dynamique des Fluides Arts et Metiers ParisTech Paris 75013 France

Valeo, involved in engine cooling fan system design for many years, is interested in noise prediction tools for axial fans. Thus, this paper describes a two-part study of tonal noise computation. The first part deals with the prediction of tonal noise using analytical models. As for the second part, it describes a hybrid approach for predicting tonal noise where the sources are extracted from an Unsteady Reynolds-Averaged Naviers-Stocks （URANS） simulation and then propagated into the far, free field using the Ffowcs Williams and Hawkings＇ acoustic analogy. The computational domain is meshed with 46 million polyhedral elements and the simulation takes into account the exact geometry of the rotor blades, the stator blades and the shroud. The results from the first part show that analytical models can be used for comparisons between different fan geometries, but are unable to provide accurate noise predictions compared to experimental results. The simulation shows non-periodic blade loading over a whole fan revolution, and different blade loading between the blades. This introduces some bias in the assessment of the acoustic performance of the fan. Overall, the results from the hybrid method are in accordance with the experimental results.

关键词： Aeroacoustics axial fan tonal noise.

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倾斜叶片垂直轴风力机气动性能的CFD研究

机电一体化 2014年第A3期20卷 20-24页

作者：颜崇浙李万莉 DOBREV IVAN mASSOUH FAWAZ 同济大学机械与能源工程学院上海201804 arts et métiers paristech Labo de Méca Fluparis75013

为了研究叶片倾斜对风力机气动性能的影响,采用三维流体计算软件FLUENT模拟了简化的倾斜叶片和直叶片风力机在自由空间的流场特性。研究表明,叶片倾斜能在不降低风力机风能利用率的情况下大幅度减小叶片上产生的驱动力矩的振动幅度;但... 详细信息

为了研究叶片倾斜对风力机气动性能的影响,采用三维流体计算软件FLUENT模拟了简化的倾斜叶片和直叶片风力机在自由空间的流场特性。研究表明,叶片倾斜能在不降低风力机风能利用率的情况下大幅度减小叶片上产生的驱动力矩的振动幅度;但是由于叶片倾斜产生的旋转半径的变化和对流场的改变,使得叶片在中间区域得到较低的力和力矩,在底端由于降低了翼尖涡流的影响增大力和力矩,而在顶端则相反地减小了力和力矩。

关键词：垂直轴风力机倾斜叶片三维模拟翼尖涡流

Performance assessment of a power-to-gas process based on reversible solid oxide cell

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 697-707页

作者： Hanaa Er-rbib Nouaamane Kezibri Chakib Bouallou Centre for Energy Efficiency of Systems MINES ParisTechPSL Research UniversityParis 75006France

Due to the foreseen growth of sustainable energy utilization in the upcoming years, storage of the excess production is becoming a rather serious matter. In this work, a promising solution to this issue is investigated using one of the most emerging technologies of electricity conversion: reversible solid oxide cells (RSOC). A detailed model was created so as to study the RSOC performance before implementing it in the global co-electrolysis Aspen Plus(Tm) model. The model was compared to experimental results and showed good agreement with the available data under steady state conditions. The system was then scaled up to a 10mWco-electrolysis unit operating at 1073 K and 3 bar. The produced syngas is subsequently directed to a methanation unit to produce a synthetic natural gas (SNG) with an equivalent chemical power of 8.3 mWth. Additionally, as a result of a heat integration analysis, the methanation process provides steam and electricity to operate the rest of the units in the process. A final CO2 capture step is added to ensure the required specifications of the produced SNG for gas network injection. Lastly, the overall performance of the power-to-gas process was evaluated taking into account the energy consumption of each unit.

关键词： renewable electricity storage co-electrolysis methanation carbone capture energy consumption Renewable electricity PROCESS GAS methanation Performance assessment synthetic natural gas Electricity

Effects of lime treatment on the microstructure and hydraulic conductivity of Héricourt clay

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Journal of Rock mechanics and Geotechnical Engineering 2014年第5期6卷 399-404页

作者： Thanh Danh Tran Yu-Jun Cui Anh minh Tang martine Audiguier Roger Cojean mines paristech-Centre de Géosciences FontainebleauFrance Laboratoire Navier/CERmES Ecole des Ponts ParisTech6 et 8 Avenue Blaise Pascal77455 Marne-la-Vallée Cedex 2France mines paristeche-Centre de Géosciences FontainebleauFrance

This study aims at evidencing the effects of lime treatment on the microstructure and hydraulic conductivityof a compacted expansive clay, with emphasis put on the effect of lime hydration and *** this purpose, evolutions of hydraulic conductivity were investigated for both lime-treatedand untreated soil specimens over 7 d after full saturation of the specimens and their microstructureswere observed at the end. Note that for the treated specimen, dry clay powder was mixed with quicklimeprior to compaction in order to study the effect of lime hydration. It is observed that lime hydration andmodification did not affect the intra-aggregate pores but increased the inter-aggregates pores size. Thisincrease gave rise to an increase of hydraulic conductivity. more precisely, the hydraulic conductivity oflime-treated specimen increased progressively during the first 3 d of modification phase and stabilisedduring the next 4 d which correspond to a short period prior to the stabilisation phase. The microstructureobservation showed that stabilisation reactions took place after 7 d. Under the effect of stabilisation,a decreasing hydraulic conductivity can be expected in longer time due to the formation ofcementitious compounds. 2014 Institute of Rock and Soil mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

关键词： Clays Lime hydration Hydraulic conductivity microstructure Temperature effect

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激光焊接中温度测量方法的对比

机电一体化 2015年第10期21卷 22-26,47页

作者：陈怀逸王伟明 morgan DAL Frederic COSTE 上海交通大学机械与动力工程学院上海200240 arts et métiers paristech Labo de Laserparis75013

应用于核能装备的奥氏体不锈钢部件经过TIG焊接后,在生产和维修过程中容易产生裂纹,严重影响相应装备的正常运行和使用寿命。研究表明裂纹的产生和生产焊接过程中的冷却温度有很大的关系。传统的接触式测温如热电偶测温法没法测量焊接... 详细信息

应用于核能装备的奥氏体不锈钢部件经过TIG焊接后,在生产和维修过程中容易产生裂纹,严重影响相应装备的正常运行和使用寿命。研究表明裂纹的产生和生产焊接过程中的冷却温度有很大的关系。传统的接触式测温如热电偶测温法没法测量焊接过程中的冷却温度。基于FLIR-SC7500多通道测温相机成功开发了一套以数字图像技术和红外热辐射测温技术为原理的双色红外测温系统,并将其测量结果和传统的单色法测温结果进行对比,表明开发的双色测温法具有可行性和有效性。

关键词：激光焊接测温双色法单色法发射率