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Particles in a circulation loop for solar energy capture and storage

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Particuology 2019年第2期17卷 149-156页

作者： Q. kang G. Flamant R. Dewil J. Baeyens H.L. Zhang y.M. Deng KU Leuven Department of Chemical Engineering Process and Environmental Technology Lab. 2860 Sint-Katelijne-Waver Belgium Processes. Materials and Solar Energy Laboratory PROMES-CNRS 66120 Font Romeu France European Powder & Process Technology 3120 Tremelo Belgium Beijing University of Chemical Technology School of Life Science and Technology Beijing 10029 China

This study defines and assesses the selection ciiteria for suitable particulate materials to be used in an upflow bubbling fluidized bed (UBFB) or dense up-flow powder circulation system for solar energy capture and storage. The main criteria identified are based on the thermophysical and thermomechanical properties, attrition behavior, and the considerations of health and environmental hazards of the candidate powders. Finally, a cost comparison and tentative ranking of the different can didate powders is presented in addition to a weighted scoring. Significant scoring differences can be observed between the various materials. Olivine possesses the most favorable characteristics and appears to be the particulate material of choice for solid/gas suspension heat transfer fluids.

关键词： Concentrated solar power Particle-in-tube receiver Particle properties Selection criteria

Support interaction of Pt/CeO2 and Pt/SiC catalysts prepared by nano platinum colloid deposition for CO oxidation

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Journal of Rare Earths 2020年第4期38卷 376-383页

作者： kang Xi yong Wang kang Jiang Jing Xie ying Zhou Hanfeng Lu Innovation Team of Air Pollution Control Institute of Catalytic Reaction EngineeringCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China

The interaction between Pt and its various supports can regulate the intrinsic electronic structure of Pt particles and their catalytic ***,Pt/CeO2 and Pt/SiC catalysts were successfully prepared via a facile Pt colloidal particle deposition method,and their catalytic performance in CO oxidation was ***,TEM,XPS and H2-TPR were used to identify the states of Pt particles on the support surface,as well as their effect on the performance of the *** of the Pt-O-Ce interaction is one of the factors controlling catalyst *** the oxidative treatment at low temperature,the Pt-O-Ce interaction plays an important role in improving the catalytic *** calcining at high temperature,enhanced Pt-O-Ce interaction results in the absence of metallic Pt0 on the support surface,as evidenced by the appearance of Pt2+*** is consistent with the XPS data of Pt/CeO2,and is the main reason behind the deactivation of the *** contrast,either no interaction is formed between Pt and SiC or Pt nanoparticles remain in the metallic Pt0 state on the SiC surface even after aging at 800℃in an oxidizing ***,the Pt/SiC shows better thermal stability than Pt/*** interaction between Pt and the active support may be concluded to be essential for CO oxidation at low temperature,but strong interactions may induce serious deactivation of catalytic activity.

关键词： Nano platinum colloid CO oxidation Pt-O-Ce interaction CeO2 SiC Rare earths

敦煌构造带南部含石墨大理岩成因及其大地构造意义

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地质科学 2024年第4期59卷 925-939页

作者：石梦岩侯泉林程南南亢怡萱河南理工大学资源环境学院河南焦作454003 中国科学院大学地球与行星科学学院北京100049

敦煌构造带位于中亚造山带南缘,关于其构造属性存在“前寒武纪稳定地块”和“显生宙造山带”两种不同观点。这一争议限制了对中亚造山带南缘增生扩展过程以及中亚构造域和特提斯构造域之间相互作用的理解。本文对敦煌构造带南部红柳峡... 详细信息

敦煌构造带位于中亚造山带南缘,关于其构造属性存在“前寒武纪稳定地块”和“显生宙造山带”两种不同观点。这一争议限制了对中亚造山带南缘增生扩展过程以及中亚构造域和特提斯构造域之间相互作用的理解。本文对敦煌构造带南部红柳峡变质杂岩出露的含石墨大理岩进行构造地质学、显微岩相学、地球化学和石墨拉曼光谱学研究。红柳峡河谷含石墨大理岩与角闪岩(具有海山玄武岩地球化学亲缘性)构造叠置或裹杂角闪岩岩块,富含橄榄石、角闪石等镁铁质矿物及其蛇纹石化产物,全岩稀土元素(REE)含量远低于后太古宙澳大利亚平均页岩(PAAS),表明原岩沉积时缺少陆源碎屑供给但有较多基性火成岩碎屑加入,推测其原岩是形成于洋底海山或洋岛之上的碳酸盐岩帽。干洪沟含石墨大理岩以夹层或透镜体形式产于云母石英片岩中,大理岩中含有石英、白云母等陆源碎屑,缺乏基性火山物质,PAAS标准化REE配分模式具有明显的Ce负异常,且全岩y/Ho比值接近PAAS,表明原岩沉积于近岸相对氧化水体环境且受陆源碎屑影响较大,推测其原岩可能是形成于增生楔斜坡盆地相的碳酸盐岩。石墨拉曼温度计揭示两类大理岩分别记录了552℃~577℃和431℃~476℃(T^(1):Rahl温度计)或534℃~539℃和472℃~503℃(T_(2):Beyssac温度计)的变质温度,暗示它们经历了不同级别的变质作用。以上结果表明,红柳峡变质杂岩中大理岩之原岩形成于海山(或洋岛)和增生楔斜坡盆地等不同构造环境,并在俯冲带经历俯冲-变质-折返-混杂等过程,是俯冲带增生杂岩的重要组分,佐证了敦煌构造带的属性为造山带而非前寒武纪地块。

关键词：敦煌构造带含石墨大理岩原岩构造环境

Optimization of a High Speed Spinning Disk Spindle System for Minimum RRO,NRRO,and Lightweight by Using G.A.

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厦门大学学报(自然科学版) 2002年第S1期41卷 89-90页

作者： y H Choi S T Kim K C yoon J M Kim y J kang Dept.of Mechanical Design and Manufacturing Changwon National UniversityKyungnam 641-773Korea Dept.of Mechanical Engineering Changwon National UniversityKyungnam 641-773Korea Senoir Research Engineer R&D Cente FAGHANWHA Bearing Corp.Kyungnam 641-020Korea Graduate Student Dept.of Mechanical Design and ManufacturingChangwon National UniversityKyungnam 6412773Korea

Law level of RRO(Repeatable Run Out),NRRO(Non Repe at able Run Out),and lightweight construction are a major trend in the high-speed HDD(Hard Disk Drive)sytem to reduce track misregestration and to achieve high track density,which lead to succeed in the ***,it is not easy to r educe RRO,NRRO,and the weight of the spinning disk spindle system efficiently because lightweight construction and or bearing stiffness changes often yields a decrease in the static and dynamic stiffness of the system,and consequently hi gh vibrations may be generated as a ***,it is of importance to e valuate in advance the accurate dynamic behavior of the high speed spinning disk spindle system of a HDD *** study introduces an optimum design of the high speed spinning disk spindle system of a HDD for minimum RRO,NRRO,and lightweight construction using a gene tic *** spinning disk,hub,and bearing components of a HDD system ar e modelled as appropriate finite elements respectively and their equations of mo tion are derived to construct the system equations of the whole spinning disk sp indle system of the HDD *** RRO and NRRO responses of the spinning disk,due to exciting forces arised from ball bearing faults and rotating unbalance,are *** the design optimation,the hub thickness,the disk thickness,bearing positio ns(or bearing span)and bearing stiffness were set as design *** uni que objective function is obtained by multiplying an appropriate weighting facto r by multi-objective functions,such as RRO,NRRO,and the total weight of HDD the *** constraints are maximum RRO limit,maximum weight linit,and the critical speed limit of the HDD spindle *** show that the RRO,NRRO,and weight are reduced by 6%,66.7%and 28%r espectively compared with the initial design of the HDD ***,thi s present study can be used for an optimum design of the spinning disk spindle s ystem of a HDD for lightweight construction

关键词： design optimization genetic algorithm multiobjective optimization repeatable run out non repeatable run out

Study on Soap-free P(MMA-EA-AA/MAA) Latex Particles With Narrow Size Distribution

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复旦学报（自然科学版） 2005年第5期44卷 738-739页

作者： K. kang C. y. Kan y. DU D. S. Liu Department of Chemical Engineering School of Materials Science and Engineering Tsinghua University Beijing 100084 China

In the past decades, more and more studies have been focused on the synthesis of monodisperse particles with different diameter by special polymerization technique. In 1980' s, Ugelstad, et al[1] invented two-step swelling method to prepare monodisperse microsphere with large size more than 1 μm. In the following decade, Okubo and his coworkers[2] synthesized monodisperse crosslinked polymer particles above 3 μm using one-step dynamic swelling method. New method has been developed to produce particles more than 50 μm in diameter with a standard deviation of less than 2%[3]. Up to now, most of the monodisperse particles were usually prepared by polymerization of St in the presence of surfactants. In this presentation, sub-micro sized P (MMA-EA-AA/MAA) particles with narrow size distribution were prepared by seeded emulsion polymerization in the absence of any surfactant materials.

关键词：乳胶粒子聚合物膨胀理论杂环化合物异丁烯酸盐

鄂尔多斯盆地吴旗-志丹地区延长组长7段泥岩地球化学特征及其地质意义

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矿物岩石 2024年第2期44卷 161-176页

作者：康李茜邓昆白斌齐荣段富豪成都理工大学四川成都610059 中国石油勘探开发研究院北京100083 中国石油化工股份有限公司华北油气分公司河南郑州450006

应用地球化学特征来识别沉积环境有着重要的地质意义。为了研究鄂尔多斯盆地吴旗一志丹地区延长组长7段泥岩地球化学特征及其地质意义,以W100、W336井钻井岩心为主,选取了18个泥岩样品,开展了主微量元素以及稀土元素的分析测试,探讨其... 详细信息

应用地球化学特征来识别沉积环境有着重要的地质意义。为了研究鄂尔多斯盆地吴旗一志丹地区延长组长7段泥岩地球化学特征及其地质意义,以W100、W336井钻井岩心为主,选取了18个泥岩样品,开展了主微量元素以及稀土元素的分析测试,探讨其古氧化还原性、古盐度、古水深、古气候、母岩来源等地球化学特征。研究结果表明:吴旗一志丹地区延长组长7段泥岩主量元素含量由SiO_(2)与Al_(2)O_(3)占据了主体,SiO_(2)质量分数最高(44.13%~60.88%,平均为53.13%),其次为Al_(2)O_(3)(13.47%~19.62%,平均值为17.64%);泥岩样品的V/(V+Ni)比值(0.50~0.88,平均值为0.73)和Ceanom值(-0.20~0.06之间,平均值为-0.04)反映了吴旗一志丹地区延长组长7段总体上呈还原环境;利用B元素含量(449×10^(-6)~1091×10^(-6),平均含量为796.28×10^(-6))和Sr/Ba比值(0.08~0.41,平均值为0.21)分析其古盐度,可知从长73到长72逐渐下降,从长72到长71又逐渐上升;Fe/Mn比值变化和钴元素质量分数w(Co)结果综合指示了长7段古水深整体呈深水环境;Sr元素含量(60.4×10^(-6)~370.0×10^(-6),平均值为172.24×10^(-6))及Sr/Cu比值结果(平均值为5.15)反映了古气候主要为温湿气候;利用δEu值(0.45~1.25,均值0.94)和泥岩La/Lb-ΣREE图解分析其母岩来源为大洋拉斑玄武岩,并利用δCe值(0.50~1.07,平均值0.73)分析其母岩所处的构造背景为大洋盆地-大陆边缘区之间的区域。

关键词：泥岩地球化学沉积环境延长组吴旗-志丹地区鄂尔多斯盆地

Effects of Weaving Laser on Weld Microstructure and Crack for Al 6k21-T4 Alloy

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Journal of Materials Science & Technology 2011年第1期27卷 93-96页

作者： B.H.Kim N.H.kang W.T.Oh C.H.Kim J.H.Kim y.S.Kim y.H.Park Department of Materials Science and Engineering Pusan National UniversitySan30Jangjeon-dongGeumjeong-guBusan 609-735Korea Department of Materials and Components Engineering Dong-Eui UniversityBusan 614-714Korea Advanced Joining Technology Team KITECH7-47Songdo-dongYeonsu-guIncheon 406-840Korea Division for Dongnam Area Technology Service KITECHJisa-dongGanseo-guBusan 618-230Korea

For Al 6k21-T4 overlap weld joint,the shear-tensile strength by using the weaving laser was improved as compared to the case of linear *** the specimen of low strength,the porosity was distributed continuously along the intersection between the plates and fusion ***,for the optimized welding condition,large oval-shaped porosities were located only in the advancing track of the concave ***,the continuity of cracks and porosities played a key role to determine the ***,the weaving width was also the important parameter to control the ***,the concave part had more significant hot and cold cracking in the weld and heat-affected zone（HAZ）,respectively,than the convex part.

关键词： Weaving laser Weld microstructure Void Al alloy

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新时代高职院校课堂革命的内涵、问题及路径

新疆职业大学学报 2024年第2期32卷 30-33页

作者：康卉侯晓方西安航空职业技术学院教务处陕西西安710089

梳理高职院校开展“课堂革命”的政策背景,明确了高职院校“课堂革命”的现实要义,在文献研究的基础上,提出了新时代我国高职院校“课堂革命”的内涵,分析了当前高职院校开展“课堂革命”的现实问题,并从政策引领、机制保障、全面推进... 详细信息

梳理高职院校开展“课堂革命”的政策背景,明确了高职院校“课堂革命”的现实要义,在文献研究的基础上,提出了新时代我国高职院校“课堂革命”的内涵,分析了当前高职院校开展“课堂革命”的现实问题,并从政策引领、机制保障、全面推进课堂革命有序发展,多措并举、项目推进、促进教师能力全面提升,校企联动、深化改革、确保课堂革命走深落实等三个方面提出高职教育开展“课堂革命”的具体路径。

关键词：高职教育课堂革命内涵路径探索

Al-5Ti-1B与y复合添加对铸造Mg-5Al-5Si合金的影响

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太原理工大学学报 2024年第3期55卷 474-482页

作者：康文旭马润山崔泽云范晋平太原理工大学材料科学与工程学院太原030024

【目的】为细化Mg-Al-Si合金中的粗大Mg_(2)Si相,添加Al-5Ti-1B和稀土y对Mg-5Al-5Si合金进行变质处理。【方法】熔炼制得不同成分的Mg-Al-Si合金,使用多种测试方法对变质前后合金成分、微观组织及力学性能进行分析,并讨论其变质机理。... 详细信息

【目的】为细化Mg-Al-Si合金中的粗大Mg_(2)Si相,添加Al-5Ti-1B和稀土y对Mg-5Al-5Si合金进行变质处理。【方法】熔炼制得不同成分的Mg-Al-Si合金,使用多种测试方法对变质前后合金成分、微观组织及力学性能进行分析,并讨论其变质机理。【结果】结果表明:在Mg-5Al-5Si合金中添加Al-5Ti-1B,初生相形貌由粗大块状转变为细枝晶状或多边形状,共晶相数量随着Al-5Ti-1B添加量的增加而减少,合金硬度显著提高,这是因为TiB_(2)为Mg_(2)Si提供了形核基底。当合金中添加1.0%Al-5Ti-1B时,再添加y会使初生相尺寸进一步减小,形貌规整。当复合添加1.0%Al-5Ti-1B和1.0%y时,初生Mg_(2)Si相平均尺寸降低到10.2μm,形貌为细小多边形状,合金拉伸力学性能最优,稀土y的变质机理主要为吸附毒化。

关键词： Mg-Al-Si合金 Mg_(2)Si 显微组织力学性能

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