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Electrochemical reactivity of In-Pb solid solution as a negative electrode for rechargeable Mg-ion batteries

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Journal of Energy Chemistry 2021年第4期30卷 124-128页

作者： Lucie Blondeau suzy surble eddy Foy Hicham Khodja Magali Gauthier UniversitéParis-saclay CEACNRSNIMBELEEL91191Gif-sur-YvetteFrance UniversitéParis-saclay CEACNRSNIMBELAPA-IRAMAT91191Gif-sur-YvetteFrance

A composite In-Pb:carbon was successfully synthetized by a two-step mechanochemical synthesis in order to obtain an adequate particles size and structure to investigate the electrochemical reactivity of the In-Pb solid solution towards Mg.A potential synergetic coupling of electroactive elements In and Pb was examined using electrochemical and ex situ X-ray diffraction analyses.The potential profile of the solid solution indicates the formation of Mg_(2)Pb and Mg In.However,the diffraction study suggests a peculiar electrochemically-driven amorphization of Mg In during the magnesiation,in strong contrast to Mg In crystallization in In-based and In Bi-based electrodes reported in the literature.Combining In and Pb favors the amorphization of Mg In and a high first magnesiation capacity of about 550 m Ah g^(-1),but is thereafter detrimental to the material’s reversibility.These results emphasize the possible influence of electrochemically-driven amorphization and crystallization processes on electrochemical performance of battery materials.

关键词： Magnesium battery Negative electrode Alloy Amorphization

satellite observed shape-based overall rotation—A new aspect in eddy kinematics

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Acta Oceanologica sinica 2022年第5期41卷 183-194页

作者： Xueqing yang Guiyan Han Chunyong Ma Chuanchuan Cao Jie yang Ge Chen school of Marine Technology Ocean University of ChinaQingdao266100China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao266237China Frontiers science Center for Deep Ocean Multispheres and Earth system Ocean University of ChinaQingdao266100China

With the development of satellite altimetry technology,the resolution of sea-level anomaly(sLA)datasets is constantly improving.Current spatial resolution levels can reach a grid size of(1/4)°×(1/4)°,with daily measurements that span from 1993 to 2018,allowing for the precise identification and tracking of individual eddies.In the current study,in addition to the internal circulation and migration of eddies,a new aspect in eddy kinematics is revealed and investigated for the first time:shape-based overall eddy rotation(sOER),based on the intrinsic elliptical shape of eddies identified from a high-resolution sLA dataset.We found that eddies can maintain an elliptical shape and a slow and stable sOER during their migration process.The sOER speed was observed to be negatively correlated to eddy lifetime,and exhibited a dependence on latitude,decreasing from low-and high-to mid-latitudes.The sOER direction tended to be consistent with the direction of internal circulation,particularly for long-lived eddies.In addition,we identified a negative relationship between internal circulation speed and sOER speed while the migration speed was positively related to sOER speed.These findings further expand and improve eddy kinematics,which is of great significance for the future study of eddy dynamics.

关键词： mesoscale eddies shape-based overall eddy rotation(sOER) internal circulation eddy migration

subthermocline eddies carrying the Indonesian Throughflow water observed in the southeastern tropical Indian Ocean

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Acta Oceanologica sinica 2023年第5期42卷 1-13页

作者： Guangbing yang Quanan Zheng Xuejun Xiong First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China shandong Key Laboratory of Marine science and Numerical Modeling Qingdao 266061China Department of Atmospheric and Oceanic science University of MarylandCollege Park 20742USA

We observed a subthermocline eddy(sTE)with a cold and fresh core during an observation cruise along a transect of 10°s in the southeastern tropical Indian Ocean(sETIO)in December 2017.The vertical scale,speed radius,and maximum swirl velocity of the sTE were about 200 m,55 km,and 0.5 m/s,respectively.The mean Rossby number and Burger number of the sTE were then estimated to be about−0.7 and 2.4,indicating the sTE was a submesoscale coherent vortex.The sTE core water had characteristics of the Indonesian Throughflow(ITF)water and was distinct from that of surrounding areas.By examining Argo float data,another sTE was well captured by five successive profiles of the same Argo float.Both sTEs showed significant temperature and salinity anomalies at theσ0=26.0-26.5 kg/m3 surfaces.With the assumption that the low-salinity ITF water parcels could be carried only by surface eddies and the sTEs,the Argo profiles,which detected low-salinity ITF water and were located outside a surface eddy,were believed to be inside an sTE and were used to analyze the distribution,origin,and generation mechanism of the sTE.The results suggested that the sTEs carrying ITF water may be generated under topography-current interaction at the eastern coastal waters or under front-induced subduction in the area away from coastal waters.Those sTEs may be widely distributed in the sETIO and may play a role in ITF water parcel transport.

关键词： subthermocline eddy southeastern tropical Indian Ocean Indonesian Throughflow submesoscale coherent vortex

Improvement of carbon fiber surface properties using electron beam irradiation

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Nuclear science and Techniques 2007年第1期18卷 39-41页

作者： eddy segura PINO Luci Diva Brocardo MACHADO Claudia GIOVEDI Instituto de Pesquisas Energéticas e Nucleares-IPEN/CNEN-sP Av.Prof.Lineu Prestes2242Cidade Universitária05508-000Sāo PauloSP-Brazil Centro Tecnológico da Marinha em sāo Paulo Av.Prof.Lineu Prestes2468Cidade Universitária05508-000Sāo PauloSP-Brazil

Carbon fiber-reinforced advance composites have been used for structural applications,mainly on account of their mechanical properties.The main factor for a good mechanical performance of carbon fiber-reinforced com- posite is the interfacial interaction between its components,which are carbon fiber and polymeric matrix.The aim of this study is to improve the surface properties of the carbon fiber using ionizing radiation from an electron beam to obtain better adhesion properties in the resultant composite.EB radiation was applied on the carbon fiber itself before preparing test specimens for the mechanical tests.Experimental results showed that EB irradiation improved the ten- sile strength of carbon fiber samples.The maximum value in tensile strength was reached using doses of about 250 kGy.After breakage,the morphology aspect of the tensile specimens prepared with irradiated and non-irradiated car- bon fibers were evaluated.sEM micrographs showed modifications on the carbon fiber surface.

关键词：碳纤维表面性质电子束辐射改性

Numerical study of the influence of dome shape on the unsteady aerodynamic performance of a high-speed train's pantograph subjected to crosswind

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第1期10卷 13-30页

作者： Xiaofang Li Dan Zhou Lirong Jia Mingzhi yang Key Laboratory of Traffic safety on Track of Ministry of Education School of Traffic and Transportation EngineeringCentral South UniversityChangsha 410075China Joint International Research Laboratory of Key Technology for Rail Traffic safety Central South UniversityChangsha 410075China National&Local Joint Engineering Research Center of safety Technology for Rail Vehicle Central South UniversityChangsha 410075China CsR Qingdao sifang Co.Ltd. Qingdao 266111China

This study aims to investigate the unsteady aerodynamic performance of a high-speed train’s pantograph with respect to two different dome shapes and without dome under a20°yaw angle using a delayed detached eddy simulation method.Further,the influence of the dome shape on the simulation results is determined.The accuracy of the numerical method was validated by comparing a few of the numerical results with the wind tunnel test results,and high consistency was observed.An analysis of aerodynamic forces and flow structures around the pantograph was performed.The dome had significant influence on velocity field distribution surrounding the pantograph,particularly in the wake of flow region.Compared with the case where the dome was absent,vortex intensity around the pantograph increased after installing the dome.The existence of the bathtub-type dome resulted in greater flow field disturbance and vortex strength than the baffle-type dome.Moreover,the dome considerably affected time-averaged aerodynamic coefficients and their fluctuations,especially the bathtub-type dome.Additionally,the power spectral density of the unsteady aerodynamic coefficient of each pantograph component exhibited significant peaks and typical broadband distribution characteristics.

关键词： High-speed train Crosswind Pantograph Dome Unsteady aerodynamic performance

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中低速磁浮列车多传感器融合测速方法

电力机车与城轨车辆 2024年第2期47卷 36-42页

作者：崔俊锋董帅强王琦周艳丽杨明春杨辉北京全路通信信号研究设计院集团有限公司北京100070 华东交通大学电气与自动化工程学院江西南昌330013

针对中低速磁浮列车测速问题,文章以凤凰中低速磁浮快线为研究对象进行分析,提出一种多传感器融合的测速方法。首先,分析涡流传感器的测速原理及其测速不准的主要原因;其次,针对中低速磁浮线路测速不准问题,从算法层面和运动学原理角度... 详细信息

针对中低速磁浮列车测速问题,文章以凤凰中低速磁浮快线为研究对象进行分析,提出一种多传感器融合的测速方法。首先,分析涡流传感器的测速原理及其测速不准的主要原因;其次,针对中低速磁浮线路测速不准问题,从算法层面和运动学原理角度提出处理方法;最后,采用卡尔曼滤波算法对涡流传感器、雷达和加速度计的信息进行融合测速。试验结果表明,当列车速度大于1 m/s时,该方法的测速相对误差在±2%之内,满足磁浮列车的测速精度要求。

关键词：中低速磁浮列车涡流传感器列车测速系统融合测速

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强氢氟酸介质中结晶的沸石的独特性质

复旦学报（自然科学版） 2022年第6期61卷 757-767页

作者：赵浩暖 DIB eddy 石点点傅广赢丁瑞琴王宋霞杨洋郎巧霖杨晓波方千荣 VALTCHEV Valentin 中国科学院青岛生物能源与过程研究所分子筛材料研究组山东青岛266101 法国国家研究中心催化与光谱实验室法国卡昂14050 吉林大学无机合成与制备化学实验室吉林长春130012

将分子筛水热结晶合成的化学体系由传统的碱性和中性介质拓展至强酸性范围,为所形成的分子筛带来一系列独特的性质,包括显著的完美晶格结构、憎水性表面、增强的热稳定性以及稳定可靠的微孔扩散性能等。本文结合前期发表的数据和新研究... 详细信息

将分子筛水热结晶合成的化学体系由传统的碱性和中性介质拓展至强酸性范围,为所形成的分子筛带来一系列独特的性质,包括显著的完美晶格结构、憎水性表面、增强的热稳定性以及稳定可靠的微孔扩散性能等。本文结合前期发表的数据和新研究获得的结果详细演示,酸性体系结晶是普适性的分子筛合成方法,所获得的分子筛产品可具有前所未有的完美晶格结构。

关键词：酸性介质中合成沸石完美晶格分子筛骨架局域均匀结构分子筛固体核磁共振

Towards a New Model for the Production of Civil status Records Using Blockchain

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Journal of Information security 2023年第1期14卷 52-75页

作者： Tankou Tsomo Maurice eddy Bell Bitjoka Georges Ngohe Ekam Paul salomon Laboratory of Electrical Engineering Mechatronics and signal Processing ENsPY1 University of Yaoundé 1 Yaoundé Cameroon

The work presented in this article focuses on document forgery. Document fraud is a generic term used to designate a fraud, a falsification of a document. The said falsification can be observed in several sectors of everyday life. For a better illustration, let’s consider a system for producing civil status forms. The birth certificate is generally the basis of any individual’s life, and if this document is falsified, it can have repercussions at several levels, particularly in the academic field, where false diplomas, false national identity cards, false passports, false marriage certificates, etc. are obtained. It is therefore demonstrated that a secure production unit for civil status forms can be beneficial to both developed and developing countries. In addition, smart contract is proposed using a private Hyperledger fabric blockchain for validation of civil status documents, and a non-state public key management infrastructure is also proposed to authenticate the nodes that will validate the transactions. This improved blockchain solves the problem of falsification of civil status documents, as false nodes can contribute to the validation of a transaction. The contribution of such a hybrid system is of paramount importance for the identity of civil status documents on the one hand and for the identity of documents in general, and the blockchain to guarantee the distributed, unforgeable, non-repudiation, transparency and disintermediation character.

关键词： Blockchain Forgery PKI Civil status Documentary Identity

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倾转机翼旋翼无人机倾转过渡状态数值模拟

现代防御技术 2024年第3期52卷 9-19页

作者：王宗辉杨云军赵弘睿赵佳祥中国航天空气动力技术研究院北京100074 彩虹无人机科技有限公司北京100074

倾转机翼旋翼无人机相较于传统构型倾转旋翼机能够显著改善悬停状态旋翼尾迹对机翼的气动干扰影响,提高飞行效率。针对该构型无人机具有复杂非定常气动特性的连续倾转过渡过程,采用由经典的分离涡模拟方法(DEs)改进得到的延迟分离涡模... 详细信息

倾转机翼旋翼无人机相较于传统构型倾转旋翼机能够显著改善悬停状态旋翼尾迹对机翼的气动干扰影响,提高飞行效率。针对该构型无人机具有复杂非定常气动特性的连续倾转过渡过程,采用由经典的分离涡模拟方法(DEs)改进得到的延迟分离涡模拟方法(DDEs)对其进行流场气动干扰计算,倾转过渡过程中无人机前飞速度、旋翼桨距角、机身与固定翼迎角以及短舱倾转角都随时间动态变化。通过与无倾转机翼传统构型对比,分析了倾转过渡过程气动性能变化以及流场机理。仿真计算结果表明,倾转初始状态无人机受到旋翼下洗流影响较小,在30°短舱倾转角以前的倾转过程,由于倾转机翼段阻力增大,导致旋翼需用拉力增大。倾转机翼段在倾转过程中产生的分离涡与旋翼下洗流尾迹产生碰撞干扰,导致在机翼翼梢位置产生更大的尾迹干扰区域,并且对内侧固定翼翼梢产生下洗效果,降低了整机升力。

关键词：倾转机翼无人机延迟分离涡模拟倾转过渡气动干扰非定常气动特性