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Behavior of Fe Powder During High-Energy Ball Milling Cooperated with Dielectric Barrier Discharge Plasma

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Acta Metallurgica Sinica(English Letters) 2013年第1期26卷 63-68页

作者： Leyang dai Marine Engineering Institute Jimei University

In this study, nanostructured Fe powders were synthesized following 10 hours of high-energy ball milling with a superimposed dielectric barrier discharge plasma （DBDP）. The mean size of the milled powder was approximately 100 nm with an average grain size of 16.2 nm. The influence of DBDP on the underlying grain refinement mechanisms during ball milling was investigated by scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, X-ray diffraction （XRD） and BET methods. Our results show that the Fe particles displayed an extraordinary plasticity during the early milling stages under the action of DBDP, and that the plastic deformation experienced by the Fe particles during this stage was more severe than that present in normal milling. A high concentration of spherical Fe particles, approximately 50-100 nm in diameter, was documented via TEM. We propose that these spherical particles were generated via high temperature disintegration as a result of DBDP electron bombardment during ball milling. Our results suggest that it may be possible to significantly refine metallic powders during milling via the superimposition of DBDP.

关键词： Dielectric barrier discharge plasma (DBDP) High-energy ball milling Nano-Fepowder Plastic deformation Elevated temperature disintegration

THERMODYNAMICS OF CERIUM CARBIDE Fe_4Ce_4C_7 IN STEEL

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Acta Metallurgica Sinica(English Letters) 1998年第2期11卷 150-156页

作者： j.z.zhang D.z.Li Guizhou Univ of Technology Guiyang China

The thermodynamics and the properties of the cerium carbide Fe4 Ce4 C7 in steel have been studied by means of metallography, electron microprobe, X-ray diffraction technique and electrolytic separation. The main results obtained can be summarized as follows: The cerium carbide CeC2 can be precipitated in cast steel and distributed along the grain boundaries. Heat treating the steel as austenite, the CeC2 transformed into ternary compound Fe4Ce4 C7, its thermodynamics of formation in steel being expressed as: ac exp(6400/T-6. 28), where 1015Kzed light, opaque in dark field and a little greyer than iron matrix in bright field. Its Vickers hardness is about 420kg/mm2 (annealed) and 750kg/mm2 (quenched). This phase in steel is stable in basic and organic solutions and can be seperated from the matrix by electrolysis. Moreover, the LaC2 in steel can not be transformed into Fe-La-C ternary compound in present investigation.

关键词： cerium carbide electrolytic separation thermodynamics

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水泥碳汇核算及其对中国碳中和的贡献

中国科学：地球科学 2024年第6期54卷 2086-2097页

作者：马铭婧黄子王娇月牛乐张文凤徐晓伟郗凤明刘竹中国科学院沈阳应用生态研究所沈阳110016 中国科学院大学北京100049 清华大学地球系统科学系北京100084 Department of Engineering Science University of OxfordOxfordOX13UK

水泥是全球用量最高、用途最广的建筑材料之一,同时水泥生产也是人为活动碳排放的重要来源之一.水泥材料中的碱性化合物能缓慢吸收周围环境中的CO_(2)发生碳化反应,形成特殊的碳汇效应.中国是水泥生产与消费大国,科学系统核算中国水泥... 详细信息

水泥是全球用量最高、用途最广的建筑材料之一,同时水泥生产也是人为活动碳排放的重要来源之一.水泥材料中的碱性化合物能缓慢吸收周围环境中的CO_(2)发生碳化反应,形成特殊的碳汇效应.中国是水泥生产与消费大国,科学系统核算中国水泥碳汇量并明确其对碳中和的贡献值得深入探讨.通过构建水泥全生命周期碳汇核算综合分析模型,发现1930~2021年中国水泥碳汇量不断增长,到2021年高达426.77Mt CO_(2)(95%置信区间CI:317.67~874.33Mt CO_(2)),相当于中国年陆地碳汇的8.10%~45.40%,全球陆地碳汇的2.51%~4.54%,是全球碳循环中不可忽视的重要因素.在此期间,水泥的累积碳吸收量约为7.06Gt CO_(2)(95%CI:5.22~9.44Gt CO_(2)),抵消了同期水泥工业过程排放(13.91Gt CO_(2), 95%CI:12.44~17.00Gt CO_(2))的50.7%.其中,水泥砂浆对碳吸收贡献最大,占总量的65.64%.从生命周期的角度看,使用阶段的水泥材料碳吸收量占比最高(90.03%).水泥碳汇核算模型不仅提高了水泥行业碳核算的准确性,而且为中国乃至全球碳中和评估提供了科学依据.水泥材料及其废弃物的未来吸收潜力巨大,应进一步加强水泥材料的生态效益,加速水泥及其废弃物的CO_(2)封存技术研发和产业化进程,助力中国早日实现碳中和目标.

关键词：水泥碳汇生命周期评价碳减排碳中和

Effect of Variable Selection on Multidisciplinary Design Optimization:a Flight Vehicle Example

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Chinese journal of Aeronautics 2007年第1期20卷 86-96页

作者： j.Roshanian z.Keshavarz MDO Laboratory Aerospace Engineering Department of K.N. Toosi University of Technology East Vafadar blvd 4th Tehranpars sq. 16579 Tehran Iran.

Different multidisciplinary design optimization （MDO） problems are formulated and compared. Two MDO formulations are applied to a sounding rocket in order to optimize the performance of the rocket. In the MDO of the referred vehicle, three disciplines have been considered, which are trajectory, propulsion and aerodynamics. A special design structure matrix is developed to assist data exchange between disciplines. This design process uses response surface method （RSM） for multidisciplinary optimization of the rocket. The RSM is applied to the design in two categories： the propulsion model and the system level. In the propulsion model, RSM determines an approximate mathematical model of the engine output parameters as a function of design variables. In the system level, RSM fits a surface of objective function versus design variables. In the first MDO problem formulation, two design variables are selected to form propulsion discipline. In the second one, three new design variables from geometry are added and finally, an optimization method is applied to the response surface in the system level in order to find the best result. Application of the first developed multidisciplinary design optimization procedure increased accessible altitude （performance index） of the referred sounding rocket by twenty five percents and the second one twenty nine.

关键词： multidisciplinary design optimization sounding rocket central composite design response surface method equation of motion of a rocket

风化过程中铼和硒的活动性及其对化石有机碳风化的指示

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中国科学：地球科学 2024年第3期54卷 760-770页

作者：张玉红汪进曲远馨朱超金章东中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710061 中国科学院大学北京100049 西安地球环境创新研究院西安710061 西安交通大学全球环境变化研究院西安710049

化石有机碳风化是地质时间尺度上重要的碳源,对全球碳循环和气候变化具有重要影响,但如何量化一直是个挑战.河水铼(Re)含量的变化被认为具有示踪流域化石有机碳风化强度的潜力,然而Re的来源及其与化石有机碳风化之间的关系还知之甚少.... 详细信息

化石有机碳风化是地质时间尺度上重要的碳源,对全球碳循环和气候变化具有重要影响,但如何量化一直是个挑战.河水铼(Re)含量的变化被认为具有示踪流域化石有机碳风化强度的潜力,然而Re的来源及其与化石有机碳风化之间的关系还知之甚少.为了更好地认识这一指标的有效性,本文选择重庆市城口县下寒武统水井沱组页岩风化剖面为研究对象,通过元素含量、逐级提取实验等分析,探讨页岩风化序列中Re和硒(Se)的活动性及其与化石有机碳风化的关系.结果表明,化学蚀变指数(CIA)从基岩到风化层逐步升高,指示增强的风化强度.根据逐级提取实验和质量迁移系数(τ)的变化发现,页岩中的Re和Se主要赋存于有机质相,风化过程中与化石有机碳同步流失,而与页岩中的硫化物矿物氧化无明显相关;风化过程中Re和Se不同的地球化学行为导致其与化石有机碳非等量流失.本研究支持Re作为示踪化石有机碳风化的指标,而Se是示踪化石有机碳风化的潜在指标.未来需要不同类型沉积岩剖面与流域相结合的研究,明确河水Re和Se的来源及其与流域化石有机碳风化之间的关系.

关键词： Re和Se 页岩活动性化石有机碳化学风化

Control of dislocation density maximizing precipitation strengthening effect

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journal of Materials Science & Technology 2022年第32期127卷 133-143页

作者： C.Xu W.j.dai Y.Chen z.X.Qi G.zheng Y.D.Cao j.P.zhang C.C.Bu G.Chen MIIT Key Laboratory of Advanced Metallic and Internetallic Materials Technology Engineering Research Center of Materials Behavior and DesignMinistry of EducationNanjing University of Science and TechnologyNanjing 210094China

The strength-ductility trade-off has been the most challenging problem for structural metals for *** strengthening is an ideal approach to enhance the strength without significantly sacrificing the *** nanoprecipitates have been successfully acquired by nanostructural design,but the number density of nanoprecipitates cannot be further *** attempted to enhance number density by introducing highly potent nucleation sites(e.g.,dislocations).However,there remains controversy over the influence of dislocations on the nucleation and growth of coherent nanoprecipitates with minimized nucleation ***,Cu-rich nanoprecipitates in an HSLA steel,as a typical type of coherent nanoprecipitates,are *** combining analytical calculation and experiments,we show that dislocations are harmful for the formation of large numbered Cu-rich nanoprecipitates in a certain density *** dislocations deprive solute atoms which decrease homogenous precipitation that cannot be compensated by the increase in heterogeneous *** such circumstance,Cu-rich nanoprecipitates have smaller number density but larger size and higher fraction of incoherent structures due to rapid Ostwald *** a result,by controlling dislocation density,the yield strength is increased by 24%without obvious loss in ductility as compared with traditional solution-quench-age *** work would help to optimize composition and processing routes that fully exploit the nanoprecipitation strengthening effect.

关键词： Cu-rich nanoprecipitates Crystallographic defects Nucleation Structural transformation Ostwald ripening

Optimization of performance of the KM2A full array using the Crab Nebula

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Chinese Physics C 2024年第6期48卷 169-178页

作者：曹臻 F.Aharonian 安琪阿西克古白云翔包逸炜 D.Bastieri 毕效军毕玉江蔡金庭曹晴曹文羽曹喆常进常劲帆陈尚明陈恩生陈亮陈林陈龙陈明君陈玛丽陈起辉陈素弘陈天禄陈阳程宁程耀东崔明阳崔树旺崔晓红崔昱东戴本忠代洪亮戴子高单增罗布 D.della Volpe 董绪强段凯凯樊军辉范一中方军方堃冯存峰封莉冯少辉丰晓婷冯有亮 S.Gabici 高博高川东高林青高启高卫高伟康葛茂茂耿利斯 G.Giacinti 龚光华苟全补顾旻皓郭福来郭晓磊郭义庆郭莹莹韩毅昂何会海贺昊宁何佳银何新波何钰 M.Heller 贺远强侯博文侯超侯贤胡红波胡铨胡世聪黄代绘黄天奇黄文俊黄性涛黄晓渊黄勇黄志成季筱璐贾焕玉贾康江琨姜晓巍姜泽军金敏康明铭柯通 D.Kuleshov.K.Kurinov 李兵兵李澄李骢李丹李飞李海波李会财李华阳李军李剑李捷李凯李文龙李文莲李秀荣李昕李一卓李哲黎卓梁恩维梁云峰林苏杰刘冰刘成刘栋刘虎刘海东刘佳刘江来刘金艳刘茂元柳若愚刘四明刘伟刘怡刘以农鲁睿罗晴吕洪魁马伯强马玲玲马欣华毛基荣闵振 W.Mitthumsiri 穆慧君南云程 A.Neronov 区子维庞彬宇 P.Pattarakijwanich 裴致远齐孟尧祁业情乔冰强秦家军 D.Ruffolo A.Sáiz D.Semikoz 邵澄宇邵琅 O.Shchegolev 盛祥东舒富文宋慧超 Yu.V.Stenkin V.Stepanov 苏扬孙秦宁孙晓娜孙志斌谭柏轩唐庆文唐泽波田文武王超王昌贝王广威王洪光王惠惠王建成汪凯王利苹王玲玉王培汉王冉王为王祥高王祥玉王阳王玉东王岩谨王忠海王仲翔王振王铮韦大明魏俊杰魏永健文韬吴超勇吴含荣武莎吴雪峰吴雨生席邵强夏捷夏君集项光漫肖迪泫肖刚辛广广辛玉良邢祎熊峥徐东莲徐仁峰徐仁新徐伟立薛良闫大海颜景志颜田杨朝文杨帆杨冯帆杨何文杨佳盈杨莉莉杨明洁杨睿智杨深邦姚玉华姚志国叶一锰尹丽巧尹娜游晓浩游智勇于艳红袁强岳华曾厚敦曾婷轩曾玮查敏张彬彬张丰张海明张恒英张建立张丽霞张力张鹏飞张佩佩张瑞张少博张少如张寿山张潇张笑鹏张云峰张毅张勇赵兵赵静赵雷赵立志赵世平郑福周斌周浩周佳能周猛周平周荣周勋秀祝成光祝凤荣朱辉朱科军左雄 LHAASO Collaboration Key Laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Tianfu Cosmic Ray Research Center Chengdu 610000China Dublin Institute for Advanced Studies 31 Fitzwilliam Place2 DublinIreland Max-Planck-Institut for Nuclear Physics P.O.Box 10398069029 HeidelbergGermany State Key Laboratory of Particle Detection and Electronics China University of Science and Technology of China Hefei 230026China School of Physical Science and Technology&School of Information Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Hebei Normal University Shijiazhuang 050024China Key Laboratory of Dark Matter and Space Astronomy&Key Laboratory of Radio Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China Tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000TibetChina National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Physics and Astronomy(zhuhai)&School of Physics(Guangzhou)&Sino-French Institute of Nuclear Engineering and Technology(zhuhai) Sun Yat-sen UniversityZhuhai 519000&Guangzhou 510275China School of Physics and Astronomy Yunnan UniversityKunming 650091China Département de Physique Nucléaire et Corpusculaire Facultéde SciencesUniversitéde Genève24 Quai Ernest Ansermet1211 GenevaSwitzerland Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China APC Universit'e Paris Cit'eCNRS/IN2P3CEA/IRFUObservat

The full array of the Large High Altitude Air Shower Observatory(LHAASO)has been in operation since july *** its kilometer-square array(KM2A),we optimized the selection criteria for very high and ultrahigh energyγ-rays using data collected from August 2021 to August 2022,resulting in an improvement in significance of the detection in the Crab Nebula of approximately 15%,compared with that of previous *** the implementation of these new selection criteria,the angular resolution was also significantly improved by approximately 10%at tens of *** aspects of the full KM2A array performance,such as the pointing error,were also calibrated using the Crab *** resulting energy spectrum of the Crab Nebula in the energy range of 10-1000 TeV are well fitted by a log-parabola model,which is consistent with the previous results from LHAASO and other experiments.

关键词： γ-ray Crab Nebula significance

Mathematical modeling and simulations of stress mitigation by coating polycrystalline particles in lithium-ion batteries

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 947-962页

作者： N.IQBAL j.CHOI S.F.SHAH C.LEE S.LEE Department of Mechanical Roboticsand Energy EngineeringDongguk University-SeoulSeoul 04620Republic of Korea

A chemo-mechanical model is developed to investigate the effects on the stress development of the coating of polycrystalline Ni-rich LiNixMnyCo_(z)O_(2)(x≥0.8)(NMC)particles with poly(3,4-ethylenedioxythiophene)(PEDOT).The simulation results show that the coating of primary NMC particles significantly reduces the stress generation by efficiently accommodating the volume change associated with the lithium diffusion,and the coating layer plays roles both as a cushion against the volume change and a channel for the lithium transport,promoting the lithium distribution across the secondary particles more ***,the lower stiffness,higher ionic conductivity,and larger thickness of the coating layer improve the stress *** paper provides a mathematical framework for calculating the chemo-mechanical responses of anisotropic electrode materials and fundamental insights into how the coating of NMC active particles mitigates stress levels.

关键词： lithium-ion battery(LIB) polycrystalline particle coating finite element simulation Ni-rich LiNixMnyCo_(z)O_(2)(x>0.8)(NMC)

THE RESEARCH ON NEW REFLECT ROAD MARK COATING

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 1064-1068页

作者： L.M. Li, z.j. Lin, X.F. Shi and G.L. Yu Fuzhou University, Fuzhou 350002, China

As the developing of the traffic and transport, road signs coating materials become important more and more. This paper introduces the development and current situation of the traffic marking coating and discusses its raw material and application operation. C 5 petroleum resin made in china is used as major material in a hot melt traffic marking coating. To get the best material composition, orthogonal test is used and wear resistant, water resistant, acidity proof, alkaline proof, adhesive strength, fluid characteristic of the coating is researched.

关键词： hot melt coating reflecting coating road sign coating