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Tribological evaluation of thermoplastic polyurethane-based bearing materials under water lubrication:Effect of load,sliding speed,and temperature

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Friction 2024年第8期12卷 1801-1815页

作者： shaoli JIANG Janet ssWONG Debashis PUHAN Tian YUAN Xiuqin BAI Chengqing YUAN state Key Laboratory of Maritime Technology and safety Wuhan University of TechnologyWuhan 430063China Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK Yusuf Hamied Department of Chemistry University of CambridgeLensfield RoadCambridge CB21EWUK

Polymers are widely used in bearing *** the case of water-lubricated stern tube bearings,thermoplastic polyurethane(TPU)-based composites are used due to their excellent wear resistance,corrosion resistance,and tunable mechanical *** tribological performance,however,depends on operating *** this work,TPU was blended with carbon fiber,graphene platelet,and ultra-high molecular weight polyethylene(UHMWPE).Friction tests of TPU based-composites against copper countersurface were carried out in water to mimic the actual operating conditions of the *** of the resulting contacts were in the boundary lubrication regime,in which friction was attributed to both contact mechanics of asperities as well as water *** results show that the viscoelasticity of TPU has a considerable impact on its tribological *** lubrication at 50°C promotes the softening of polymer surface material during sliding,resulting in higher fluctuation in the coefficient of friction and wear *** is attributed to the reduced thermomechanical *** addition,schallamach waviness is observed on worn *** tribological properties of TPU are significantly improved by the inclusion of carbon fiber,graphene platelet,and *** formation of graphene transfer-layers and UHMWPE transfer film reduces friction and wear loss,while the inclusion of carbon fiber enhances wear resistance due to improved mechanical properties and load bearing capacity.

关键词： friction thermoplastic polyurethane(TPU) water-lubricated bearings graphene platelet carbon fibers ultra-high molecular weight polyethylene(UHMWPE)

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Early J_2 basalts in sE China:Incipience of large-scale late Mesozoic magmatism

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science China Earth sciences 2006年第8期49卷 796-815页

作者： XIE Xin1, XU Xisheng1, ZOU Haibo2, JIANG shaoyong1, ZHANG Ming3 & QIU Jiansheng1 1. state Key Laboratory of Mineral Deposit Research, Department of Earth sciences, Nanjing University, Nanjing 210093, China 2. Department of Earth and space sciences, University of California at Los Angeles, Los Angeles, CA90095-1567, UsA. 3. GEMOC ARC National Key Centre, Department of Earth and Planetary sciences, Macquarie University, sydney, N.s.W. 2109, Australia state Key Laboratory of Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing China Department of Earth and space sciences University of California at Los Angeles Los Angeles USA GEMOC ARC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney Australia

Magmatism in sE China was dormant during 204―180 Ma, but was reactivated in 180― 170 Ma (early J2), and then became more and more intensive towards the end of early Cretaceous. The small-scale early J2 magmatism is the incipience to long-term and large-scale magmatism in this region. A near east-west (ew) trend volcanic belt was distributed across south Hunan, south Jiangxi and southwest Fujian was formed during early J2 time. Along this belt from the inland toward the coast, the lithology of basalts changes from alkali into tholeiite, and the amount of erupted volcanic rocks and the proportions of rhyolites coexisting with the basalts increase. On the basis of geochemical char- acteristics of these basalts, we infer that the melting degree of source rocks and the extent of frac- tional crystallization and crustal contamination all increased whereas the depth of mantle source de- creased from the inland to the coast, which led to the variations of geological characteristics of the volcanic belt. In early J2, the western spreading Pacific plate began to subduct underneath sE China continental block, reactivating near ew trend deep fault that was originally formed during the Indos- inian event. The stress of the western spreading Pacific plate and the extent of asthenosphere up- welling increased from the inland to the coast, which is consistent with the generation and evolution of early J2 basalts.

关键词： early J2 basalts, upwelling of asthenosphere, large-scale magmatism, sE China, the Pacific plate.

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Integrating biomechanical and motor control principles in elite high jumpers： A transdisciplinary approach to enhancing sport performance

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Journal of sport and Health science 2015年第4期4卷 341-346页

作者： James Becker Will ew. Wu Department of Kinesiology California State University Long Beach CA 90840 USA

Background： In recent years, there has been a proliferation of technology and sport science utilized within an athlete＇s training, especially at the elite level. However, the sport science is a broad field, encompassing disciplines such as biomechanics, motor control and learning, exercise physiology, sports medicine, sport psychology to name a few. Rarely are these disciplines applied in an integrated manner. The purpose of this study was to document the effectiveness of an integrated biomechanics and motor control protocol for improving athlete＇s performance in the high jump. Methods： Four elite high jumpers performed baseline jumps under no^mal conditions and then jumps using a specific external focus of attention cue designed to improve their running posture. Three-dimensional biomeehanical analysis was used to quantify the upright posture throughout the approach as well as horizontal velocity at plant and vertical velocity at takeoff. Results： The results showed that when using the external focus of attention cue, the jumpers were significantly more upright during the approach, had significantly higher horizontal velocities at plant, and generated significantly greater vertical velocities during the takeoff. Conclusion： The results of this study lay the foundation for future work examining how integrating sport science disciplines can improve performance of elite level athletes.

关键词： Biomechanics High jump Motor control sport performance

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2005年日本爱知世博会波兰馆,爱知县,日本

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世界建筑 2005年第5期 52-55页

作者： Ingarden &ew■ , Architekci 因加尔登和尤维建筑师事务所

波兰馆被设计成了一个隐喻性的空间,从属于2005年日本爱知世博会的主题:'宇宙、生命和信息--生活的艺术--生态社区的发展'以及波兰展览的主旋律:'发现美',集中在弗雷德里克·肖邦和克拉科夫附近的维利奇卡盐矿身上.创造这个空间的主要... 详细信息

波兰馆被设计成了一个隐喻性的空间,从属于2005年日本爱知世博会的主题:'宇宙、生命和信息--生活的艺术--生态社区的发展'以及波兰展览的主旋律:'发现美',集中在弗雷德里克·肖邦和克拉科夫附近的维利奇卡盐矿身上.创造这个空间的主要元素有:一个试验性的柳条立面以及一个象征波兰的横断面--从北部的波罗的海到南部的山脉.展馆的立面是通过一个基于双向弯曲钢架模块化系统的模型技术形成的,周围编织着白色的柳条.这种材料的使用代表着波兰的自然景观和肖邦音乐中的自然环境.立面的高科技外形通过计算机模型生成,而它将由一些来自波兰鲁德尼克-桑河的手工艺术家亲手编织而成.

关键词：世博会波兰日本爱知县生态社区信息

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民国时期江西省城市用地与城市化水平

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地理学报 2018年第3期73卷 550-561页

作者：万智巍贾玉连蒋梅鑫刘影洪祎君卢成芳江西师范大学地理与环境学院鄱阳湖湿地与流域研究教育部重点实验室南昌330022 中国科学院地理科学与资源研究所中国科学院陆地表层格局与模拟重点实验室北京100101

定量重建历史时期城市土地利用规模、结构和城市化水平数据集有助于更好地模拟土地覆被变化的环境效应。根据日本侵华战争军事地形图资料,在Arc GIs平台定量重建民国时期江西省范围内县级以上城市用地规模和结构,取得了一套可用于历史... 详细信息

定量重建历史时期城市土地利用规模、结构和城市化水平数据集有助于更好地模拟土地覆被变化的环境效应。根据日本侵华战争军事地形图资料,在Arc GIs平台定量重建民国时期江西省范围内县级以上城市用地规模和结构,取得了一套可用于历史时期土地利用模型的城垣周长、城市用地面积、城垣内非建设用地、城垣外建设用地情况的综合数据集,并在此基础上分析了县域尺度下的土地城市化水平。与更为详细的大比例尺地图的比较表明,本套数据集误差在±10%之内。有"城内田"现象的城市为20个,有"城外市"现象的城市为28个,分别占江西省全部城市数的25%和35%。城市用地重建结果表明,江西省80个县级及以上城市总建设用地面积为87.99 km2,约占全省总面积的0.053%。民国时期江西的整体城市化率为0.047%,最高的南昌为0.19%,最低的遂川县仅为0.007%,城市化水平与县域人口总量呈正相关(r=0.457,P1)。空间格局分析表明,江西省县域城市化水平具有北高南低的特点。江西省民国时期城市用地和城市化水平数据集可以为相关全球环境变化模型提供直接的用地基础数据。

关键词：民国时期江西省城市用地城市化水平土地利用/土地覆被变化

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产后新发性和持续性高血压的流行病学及其发病机制

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中华高血压杂志 2015年第11期23卷 1084-1086页

作者： Goel A Maski MR Bajracharya s Wenger JB Zhang D salahuddin s shahul ss Thadhani R seely ew Karumanchi sA Rana s 《中华高血压杂志》编辑部

妊娠期高血压疾病是全球范围内孕产妇发病率和死亡率增加的一个常见原因。最近世界卫生组织对全球数据进行了系统回顾,发现妊娠期高血压疾病是发展中国家孕产妇死亡的主要原因,约占全球孕产妇总死亡人数的18%。即便在孕产妇死亡率极低... 详细信息

妊娠期高血压疾病是全球范围内孕产妇发病率和死亡率增加的一个常见原因。最近世界卫生组织对全球数据进行了系统回顾,发现妊娠期高血压疾病是发展中国家孕产妇死亡的主要原因,约占全球孕产妇总死亡人数的18%。即便在孕产妇死亡率极低的西方国家,妊娠期高血压疾病仍与孕产妇未来发生高血压、缺血性心脏病和脑卒中显著相关。

关键词：持续性高血压 postpartum 缺血性心脏病总死亡人数正常血压分位数发病机制先兆子痫初产妇西方国家

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Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau: Implication for geody- namic setting and duration of the Cu mineralization

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science China Earth sciences 2004年第3期47卷 221-231页

作者： HOU Zengqian1, QU Xiaoming1, WANG shuxian2, DU Andao2, GAO Yongfeng3 & HUANG Wei4 1. Institute of Mineral Resources, Chinese Academy of Geological sciences, Beijing 100037, China 2. National Center of Geoanalysis, Chinese Academy of Geological sciences, Beijing 100037, China 3. shijiazhuang College of Economy, shijiazhuang 056000, China 4. Xizang Bureau of Geology and Mineral Resources, Lhasa 850000, China Institute of Mineral Resources Chinese Academy of Geological Sci. Beijing 100037 China National Center of Geoanalysis Chinese Academy of Geological Sci. Beijing 100037 China shijiazhuang College of Economy Shijiazhuang 056000 China Xizang Bureau of Geol./Mineral Rsrc. Lhasa 850000 China

The Gangdese porphyry copper belt consists of one large and five middle-small deposits in addition to dozens of ore-bearing porphyry bodies. The belt trends 350 km long along the ew-striking Gangdese batholith, and locally occurs as a string of beads extending about 50 km within the sN-trending rifting zones (grabens) on the Tibetan plateau. Monzonitic granite- porphyry and quartz monzonitic porphyry, as dominant host rocks, are shoshonitic and potassic calc-alkaline. Available dating data indicate that the ages of the shallow-level emplacement for these porphyries vary from 10 Ma to 18 Ma, which are identical to that of associated potassic calc-alkaline volcanic rocks (10—15 Ma) and mafic dykes (13—18 Ma). The timing and duration of Cu mineralization events are constrained by Re-Os ages for molybdenites from three porphyry copper deposits in the Gangdese porphyry copper belt. Five molybdenite samples from the Nanmu deposit yielded an 187Re-187Os isochron with a highly pre-cise age of (14.76?.22) Ma; six molybdenites from the Chongjiang deposit gave an isochron age of (14.04?.16) Ma. Re-Os model ages for two molybdenite samples from Lakang抏 deposit vary from 13.5 Ma to 13.6 Ma, which are basically identical to isochron ages mentioned above. All the thirteen samples from these three deposits yielded a linear array in the isochron diagram with a higher correlation coefficient of 0.99719 and an isochron age of (14.39?.22) Ma (1s error), suggesting an coeval event of the Cu mineralization and a shared source of ore materials for the Gangdese porphyry copper belt. Compared with the longer-lived felsic magmatic-hydrothermal system, the Cu mineralization is a relatively short event with duration of about 0.5 Ma, and usu-ally occurs in the later-stage of the complicate magmatic system. The emplacement age of the Gangdese porphyries indicates that they intruded after the rapid rising of the Gangdese Mountains at 21—23 Ma, and formed in a post-collision crustal ex-tension env

关键词： porphyry copper deposit, Re-Os age, Gangdese, Tibetan plateau.

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A Positive Analysis for BPR of the Third Party Logistics

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厦门大学学报（自然科学版） 2002年第S1期41卷 231-232页

作者： LI Yan-feng 1, WU Xiao-song 2 (1. Management school, Huazhong University of science and Technology, Wuhan 430074, China 2. Information Management school, Yunnan University of Finance and Trade, Kunming 650221, China)

Facing the opportunities and challenges of China’s en try into WTO, logistics enterprises take BPR as an important way to improve the core *** modern logistics is a systematic engineering and its require ments are the standardization and normalization for enhancing the Chinese enterp rises’ level of logistic *** paper reveal the importance of manageme nt technique,information technique and business model in enterprise’s BPR throug h the positive analysis for business process of the third party logistics as a new system after reengineering businees process. Reorganization of marketing target. The characters of business procedure after N ew sunshine recomposed include: "the last mile " service systems of logistics; s etting up HUB to control many end-points in big and middle cities, setting up s ingle-points in small cities, the small parts acting delivering system which st yle of "assembly and allot" are made of in. Reorganization of business model. The New sunshine reorganized has three aspects of business model which set up: HUB, end-point and single-point. Reorganization of business *** mainly business process of restructure Ne w sunshine include : standard quote declaring prices to all attendants; on line, timely and exactly declaring prices; The net contract of B2C work on line; Tran smit to attendant; Logistice operating; feedback the working information; User t rack goods condition; settling information; paying and so on, the different busi ness can separate into kinds of right corresponding to the business process, suc h as the picture of distributing parcel, ordering, moving, picking, transporting , delivering, information, inquiring and settling. set up standard systems. Aims to execute standard management is to make distribu te and logistics for norm and standard, according to the resources share tog ether with the progresses especially and base on reducing the necessary expenses to reduce the living expenses, while low cost

关键词： third party logistics management technique info rmation technique business model

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锂硫电池用石墨烯基材料的研究进展

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物理化学学报 2018年第4期34卷 377-390页

作者：陈克孙振华方若翩李峰成会明中国科学院金属研究所沈阳材料科学国家联合实验室沈阳110016 上海科技大学物质科学与技术学院上海201210 清华大学、清华-伯克利深圳学院广东深圳518055

锂硫电池因其理论能量密度高、资源丰富和环境友好等优势,被认为是最有发展前景的下一代电化学储能系统之一。然而,硫的绝缘性、充放电中间产物多硫化物的溶解和扩散、硫的体积膨胀以及锂负极安全性等问题,严重制约着锂硫电池的商业应... 详细信息

锂硫电池因其理论能量密度高、资源丰富和环境友好等优势,被认为是最有发展前景的下一代电化学储能系统之一。然而,硫的绝缘性、充放电中间产物多硫化物的溶解和扩散、硫的体积膨胀以及锂负极安全性等问题,严重制约着锂硫电池的商业应用。石墨烯因其具有高导电、高柔性等诸多优异特性而被广泛研究,将其用于锂硫电池的正极载体、隔膜涂层和集流体中,以期实现高比能、高稳定性的锂硫电池。本文综述了石墨烯基材料,包括石墨烯、功能化石墨烯、掺杂石墨烯和石墨烯复合物,在锂硫电池中应用的研究进展,并展望了锂硫电池用石墨烯基材料的未来发展方向。

关键词：锂硫电池石墨烯掺杂功能化复合材料

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阿尔金北缘喀腊达坂火山岩型铅锌矿床研究

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地质学报 2017年第8期91卷 1818-1835页

作者：陈柏林祁万修崔玲玲陈正乐刘兵赵雷蒋荣宝韩凤彬李丽刘荣中国地质科学院地质力学研究所北京100081 新疆地质矿产勘查局第一区域地质调查大队乌鲁木齐830011

火山成因块状硫化物矿床越来越受到重视,喀腊达坂铅锌矿位于北东向阿尔金走滑断裂与东西向阿尔金北缘断裂夹持的喀腊大湾地区,是阿尔金北缘红柳沟—拉配泉金、铜、铁及多金属成矿带中唯一大型铅锌矿床。矿区主要出露奥陶系下统卓阿布拉... 详细信息

火山成因块状硫化物矿床越来越受到重视,喀腊达坂铅锌矿位于北东向阿尔金走滑断裂与东西向阿尔金北缘断裂夹持的喀腊大湾地区,是阿尔金北缘红柳沟—拉配泉金、铜、铁及多金属成矿带中唯一大型铅锌矿床。矿区主要出露奥陶系下统卓阿布拉克组火山沉积岩系,呈近东西走向,以向北中等角度倾斜的单斜层为特点,倾角30°~58°;矿化严格受火山沉积岩特定层位和岩性控制,即矿体均产于卓阿布拉克组第四亚组的中酸性火山岩(流纹岩、英安熔岩、英安质晶屑凝灰岩)中,矿体具有层状、似层状特点,产状稳定延伸大;最大矿体走向延伸超过2400m,倾向延深大于900m。主要有用组分Pb、Zn,伴生有用组分Cu、Au、Ag、s等。主要蚀变类型有黄铁矿化、硅化、绢云母化,地表氧化带形成黄钾铁钒化和褐铁矿化。矿石平均铅同位素组成为^(208)Pb/^(204)Pb=38.1169、^(207)Pb/^(204)Pb=15.6278、^(206)Pb/^(204)Pb=18.4684,显示矿石的铅具有上地壳铅和造山带铅的混合来源;矿石硫同位素组成平均+8.28‰,代表了海相沉积岩来源的硫与岩浆岩来源硫的混合;矿石稀土元素配分曲线与矿区及喀腊大湾地区中酸性火山岩的稀土元素配分曲线具有一致性或者相似,说明矿石与含矿中酸性火山岩具有一致的成因与来源;矿石微量元素特征显示Nb、Ta负异常与Ba的正异常,反映出存在海相沉积岩物质的混入,并具有岛弧成矿构造环境。含矿火山岩锆石sHRIMP U-Pb年龄482~485Ma,代表了矿床的形成时代为早古生代早奥陶世。综合喀腊达坂铅锌矿地质地球化学特征的研究,确认其属于火山成因块状硫化物矿床(VMs型)。所以,喀腊达坂铅锌矿成矿过程可以概括为:在早古生代奥陶纪早期北阿尔金洋发生向南的板块俯冲,板块俯冲作用导致俯冲带下盘的洋壳及其上的海相沉积物和俯冲带上盘的陆壳发生部分熔融,形成了中酸性岛弧型岩浆;在岩浆喷发的晚期,逐渐形成富含铅锌成矿物质的残余岩浆;当这些富含铅锌的残余岩浆发生喷发,最终形成了火山成因岩块状硫化物型铅锌矿床。火山岩型铅锌多金属矿床是阿尔金北缘喀腊大湾地区南带最重要勘查和预测类型,该火山岩型矿化带的西延区段是有利的找矿靶区。

关键词：火山成因块状硫化物矿床形成时代岛弧成矿构造环境喀腊达坂铅锌矿床阿尔金北缘

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