2,740 research outputs found

    Colloquium: Graphene spectroscopy

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    Spectroscopic studies of electronic phenomena in graphene are reviewed. A variety of methods and techniques are surveyed, from quasiparticle spectroscopies (tunneling, photoemission) to methods probing density and current response (infrared optics, Raman) to scanning probe nanoscopy and ultrafast pump-probe experiments. Vast complimentary information derived from these investigations is shown to highlight unusual properties of Dirac quasiparticles and many-body interaction effects in the physics of graphene.Comment: 36 pages, 16 figure

    Effects of Biochar Application on Nitrogen and Phosphorus Availability in Soils: aReview

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    利用生物炭在贫瘠的土壤上培育出肥沃的"黑土"正成为土壤学家研究的热点.氮、磷等大量养分是衡量土壤肥力高低的重要指标,生物炭对其有效性影响表现出极大的复杂性.不同研究得出的结论不尽相同,关键是缺乏对其机制的深入研究.由于氮和磷的不合理利用还可能造成非点源污染而带来环境风险,再加之生物炭施用的不可逆性,必须确保生物炭在任何情况下都不会对土壤和环境带来不利的影响.为此,本文综述了生物炭添加对氮肥和磷肥在土壤-植物系统迁移转化过程中的作用,重点讨论了不同生物炭处理方式对土壤磷素吸附解吸和形态转化的影响,生物炭对土壤氮素转化的关键过程(矿化作用、硝化作用和固持作用)的影响,以及生物炭C/N比值对土壤氮素..

    Effect and mechanism of positively charged material on platelet accumulation

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    背景:在正常生理状态下,血小板和血管内皮细胞表面均带有不等量的负电荷,血管内皮细胞和血小板表面通过负电荷相互排斥可防止血小板与血管内壁的接触,保持血流通畅。在血管壁内外侧之间存在着跨血管壁电势差(Transvascularelectricpotential,TVEP),当血管受损时,血管伤口周围的电势发生改变,形成指向伤口方向的损伤电场(Injury-inducedelectricfield,IIEF)。本课题组的前期研究发现,在生理性止血过程中,该损伤电场可促进血小板聚集。因此我们推断正电荷物质可以促进血小板聚集,从而加速止血过程。 目的:本实验以KM小鼠肠系膜小血管为研究对象,采用电生理...Background: Under normal physiological condition, negative charges on the surface of platelets and vascular endothelial cells prevent the circulating platelets to adhere to the blood vessel. It has been shown that the intimae of blood vessel has negative transvascular electric potential (TVEP) with respect to the adventitia. When a vascular injury happens, the injury short-circuits the TVEP and in...学位:理学硕士院系专业:医学院_微生物学学号:2452014115345

    非离子态氨对转“全鱼”生长激素基因鲤鱼的急性毒性和慢性毒性

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    在自然水体和人工水体中氨氮对鱼类是有毒的.利用静水更新式生物测试研究了非离子态氨对转基因鲤鱼和对照鱼的96h急性毒性实验和21d慢性毒性实验.通过96h非离子态氨急性毒性实验发现,转基因鲤鱼的非离子态氨氮24,48,72和96h半数致死浓度(LC50)(2.64,2.44,2.28和2.16mg/L)分别比对照鲤鱼相应的24,48,72和96h半数致死浓度(LC50)(2.70,2.64,2.52和2.33mg/L)略低,没有显著性差异;但在不同非离子态氨氮(3.86,3.29和2.09mg/L)胁迫下

    1991 study on the state of existence of iron plates and organs1991年关于铁板和器官存在状态的研究报告

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    This is Zhang Bo\u27s proposal. This paper contains information about the project\u27s locations, medium, operator, instructor, and assistant. (Zhuocheng Jiang \u2726)https://digital.kenyon.edu/zhoudocs/1445/thumbnail.jp

    Create Success of Global Oil and Gas Equity M & A

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    随着全球油气资源的日益枯竭,以及世界石油、石化工业日益激烈的竞争,国际原油价格持续逐级攀升,这给作为原本石油资源就极度匮乏又需要保持经济相对高速增长的中国政府及中国石油产业的领军企业:中石油(CNPC/PetroChina),中石化(SINOPEC)和中海油(CNOOC)出了一个非常严峻的课题,三大石油公司需要责无旁贷地承担起解决中国经济对巨大原油需求缺口的重任。上游总体储量对于石油公司而言,是衡量其核心竞争力的重要指标,随着原油价格的上涨,对于半数以上内需的成品油需要依赖进口原油提炼的中国三大石油公司,其利润被进口油油价的逐渐推高完全吞噬殆尽了;雪上加霜的是,国际投资集团的热钱不失时机地轰炒...In recent a decade, as the global resources of oil and gas are depleting; it results in increasingly rise the competition level in the petroleum and petrochemical industry, it provides a sense of urgency that helps the country security successfully overcome the crisis defensively and economically. As the three giants of Chinese oil energy industry, PetroChina, Sinopec and CNOOC, being challenged ...学位:工商管理硕士院系专业:管理学院高级经理教育中心(EMBA项目)_高级管理人员工商管理硕士(EMBA)学号:X200815607

    Mobile Hand Map Service Based on Mobile Agent Technology

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    随着3G时代的到来,手机各项高层业务和应用层出不穷。其中,手机地图业务,是一项非常新兴且有很广阔的市场和重要应用价值的业务。手机地图,是指用户在手机上利用GPS技术实现精确定位,并使用WAP方式或客户端方式,通过移动通信网络与手机地图应用服务器互联通信,查找自己、好友的位置信息,查询周边兴趣点信息、查询行车路线的一种与地理信息相关的位置服务业务。用户在查询过程中,不仅可以得到相关的文字说明信息,同时还可以通过人机界面得到更详细、更直观的地图信息和动画导航。 移动主体(MobileAgent,MA)技术是一种新的软件设计模式,具有自主性、交互性和移动性等特性。移动主体技术为手机地图业务提供了一...Nowadays, mobile phone becomes an indispensable tool for communication and entertainment, and plays a very important part in people’s life. With the coming age of 3G time, more and more service and applications come out, one of which is hand map service. Hand map service is a new service but has a wide market foreground and significant meanings. Using of GPS technology to achieve high quality orie...学位:工程硕士院系专业:软件学院_工程硕士(软件工程)学号:X200623008
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