243 research outputs found

    Electrochemical Sensing Based on Modified Conical Micropore Electrodes

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    超微电极由于其优良的电化学特性和超小的尺寸,可实现高时间分辨及高空间分辨实时监测单细胞、单囊泡释放及突触间隙化学信号分子传导,自引入到电化学和电分析化学领域后引起了电分析化学前所未有的发展。另一方面,纳米孔由于其纳米级别的几何尺寸与生物膜的结构相近,被广泛用于构建仿生离子通道,在分子水平上对组成和调控生命体系结构和运行的离子,生物分子和小分子进行检测和分离。本论文致力于制备锥状微孔电极,与柱状孔电极相比,锥形孔道具有更小的传质阻力,在给定电压下对被检测物质具备更高的响应灵敏度。对锥形微孔电极进行相应的修饰可实现对不同物质的灵敏和选择性响应,并且微孔道空间的存在可使电极的修饰更牢固,修饰量更大,...Electrochemical detection based on ultramicroelectrodes has evoked widespread research interest and has been studied in many fields comprehensively and intensively owing to its intrinsic advantages such as fast response, excellent sensitivity, high spatiotemporal resolution and small size. On the other hand, because of its nanoscale size and geometry which are similar to the membrane, significant ...学位:理学博士院系专业:化学化工学院化学系_分析化学学号:2052006015321

    the research of Chinese Advertising Industrial Organisation

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    广告业是第三产业中很重要的一个部门。广告对拉动消费、扩大内需都有着积极的作用。随着市场经济体制的逐步确立,我国的广告产业从无到有,发展迅速,具有极大的发展前景。但自从我国对外开放广告业以来,我国广告产业正在经历着巨大变化,外资企业的进入和对国内企业的并购,虽一定程度地改变着我国广告产业市场集中度低的局面,但外资的加入竞争也使我国广告产业组织原本就存的问题更加凸显。因此,有必要从产业组织角度对中国广告产业进行比较系统的研究。 本文从我国广告产业的发展历程和现状出发,运用产业组织理论中SCP框架对广告产业的市场结构、市场行为和市场绩效等进行了分析,并指出了我国广告产业组织存在的主要问题。 我国...The Advertising Industry has played an important role in chinese economy. Domestic consumption can be actively increased by advertising. Starting from stratch, Chinese Advertising Industry has great developing prospects.With the establishment of marketing ecnomic system, Chinese Advertising Industry has undergone change .Athough the entering of foreign corporation and its merge of domestic corpora...学位:经济学硕士院系专业:经济学院经济研究所_产业经济学学号:2902007115039

    公共部门引进ISO9000管理体系的探讨

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    如何加强对公共部门的质量管理是真正推进以“行政三分”法改革的关键环节。因此,作为企业质量管理的权威认证的ISO9000质量认证、管理方法和体系为我们新一轮行政改革中加强公共部门质量管理提供了可供借鉴的模式

    Theory about the Accountability of Government Regulation and its Performance——Analysis from an Economic Scope

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    从经济与公共管理理论相结合的视角来看,政府规制是一种委托——代理的受托责任的承担和履行。本文正是以委托——代理的理论为基础,以政府受托责任为切入点,深入、细致的分析政府规制受托责任的承担及其履行对企业、市场的影响,全文分为以下四个部分:第一部分:政府规制受托责任。主要是对政府规制的理解和界定的比较分析。论述政府规制与政府受托责任之间的相互关系,从而引出规制受托责任的框架和内容。第二部分:政府规制受托责任的履行。介绍了政府规制的工具,并以实际的统计资料和政府微观规制行为为基础,运用数理统计与经济分析对规制影响企业和市场的表现进行了分析和评价,归纳了政府与企业围绕规制所形成的合作的和非合作博弈规制...View from a combined scope of Economic and Public Administration, Government Regulation is a kind of Accountability’s undertaken and performed which is come from Principal---Agent relationship. The paper is just based on this Principal—Agent theory and use Government Accountability as a cut point to make a deeply analysis about the undertaken of this Accountability and the impaction on enterprise ...学位:管理学硕士院系专业:法学院政治学与行政学系_行政管理学号:20020600

    Preparation, storage and experimental conditions of biofluid samples for NMR based metabolomics

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    自1999年Nicholson及其同事在核磁共振(NMR)研究的基础上提出代谢组学概念以来,基于NMR代谢组学得到了迅速地发展。目前基于NMR代谢组学的主要研究对象是体液样品的NMR谱。由于生物体液的储存、样品制备和实验条件都会对实验结果产生影响,因此研究样品制备、储存及实验条件可以了解外界条件对样品的具体作用效果,从而通过控制外界环境及人为操作,以保证试验数据的稳定性和可比较性。 本文以基于NMR代谢组学试验中的人体的尿液、血液和全唾液为主要研究对象,研究各类样品的储存、制备和制取NMR谱图实验参数对NMR实验的影响,结合模式识别分析方法,得到适宜用于高通量试验的较合理参数。主要内容及结论...The NMR-based metabonomics approach evolved from the pioneering work of Nicholson and co-workers in 1999 has become a novel analytical technique. At present, main targets of NMR-based metabonomics experiments are biofluids, and the experiment results are sensitive to the experimental conditions, sample storage and preparation. Study of these external conditions is important to keep the stability a...学位:理学硕士院系专业:物理与机电工程学院物理学系_无线电物理学号:1982006115180

    The Review of the Scope of the Illegal Evidence Elimination Rule in China

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    在非法证据排除规则的制度中,非法证据排除规则的适用范围是居于提纲挈领的地位。我们在司法实践中要准确适用非法证据排除规则,明确非法证据排除规则的适用范围是首要问题。科学界定非法证据排除规则适用范围,我们既要借鉴国外的成熟经验,也要结合中国国情,要从中国实际出发,切实处理好坚持发现、惩罚犯罪与保障人权的相互关系。 因而,本文从我国非法证据排除规则适用范围的规范分析入手,指出其中的不足,再通过对美、英、德、日四国非法证据进行考察,从中汲取先进经验并提出进一步的完善建议。 本文除引言和结语外,正文内容共分为以下三部分: 第一部分,主要是对我国目前非法证据排除规则的适用范围的规范分析。首先对我国非...The scope of application of the illegal evidence exclusionary rule plays a significant role in the system of the illegal evidence exclusionary rule. We should determine the scope of application of the illegal evidence exclusionary rule preferentially, so that we could apply the illegal evidence exclusionary rule accurately in judicial practice. In order to determine the scope of application of the...学位:法学硕士院系专业:法学院_法律硕士学号:X201012009

    从资源管理到资产经营——论我国城市土地管理模式的转变

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    “经营土地”是城市治理市场化条件下政府加强土地资产管理的新理念,其实质就是要运用市场经济手段,对土地资产实行市场化运作,实现土地资源的优化配置,从而实现土地资产的价值。从资源管理型转变为资产经营型,这是我国城市土地管理改革的必然选择与现实取向

    基于浮动车数据的新能源汽车充电站选址布局研究——以广州中心城区为例

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    新能源汽车推广是未来减少温室气体排放、替代传统能源的手段,而充电基础设施能否满足充电时空需求对成功推广至关重要。本文以广州市中心城区为案例对充电需求进行时空特征分析,并在此基础上提出充电时空需求的最大覆盖模型,探求在一定充电站数量下的充电站最佳选址布局区域。结果表明,广州市中心城区出租车出行距离较短,行程间时长多集中在0~20min内;充电需求高度集聚,其分布呈现\"80/20\"定律,工作日与非工作日间差异不明显。分析预选充电站5、10和15min内的服务覆盖区,广州市中心城区应选择紧凑型的充电站布局(w1=0.5)。国家自然科学基金(41171139

    Unusual Boron-Carbon Compounds Containing Planar Tetracoordinate and Pentacoordinate Carbons

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    采用密度泛函理论(dfT),在b3lyP/6-311+g**水平上,研究了三类包含平面四配位碳原子(PTC)和平面五配位碳原子(PPC)的硼碳化合物.这三类新型化合物是由C3b2H4(包含PTC)、Cb4H2(包含PTC)和Cb5H2(包含PPC)三种稳定结构和—CHCH—单元连接起来而得到的.在理论上探讨了这些新型的硼碳化合物的成键特征,光谱性质以及芳香性.研究结果表明:包含PTC和PPC原子的能量最低的结构,在不受对称面限制的条件下,具有C2V对称性的顺式立体构型比具有反式平面构型的化合物稳定.计算的核独立化学位移(nICS)显示,这些新型化合物的三元环中心有强的芳香性.计算最稳定硼碳化合物的PTC和PPC原子的WIbErg键指数(WbIS)表明PTC和PPC的成键遵循八隅规则.Unusual boron-carbon compounds containing planar tetracoordinate carbon (ptC) and planar pentacoordinate carbon (ppC) were investigated using density functional theory (DFT) at B3LYP/6-311+G** level.These novel compounds are generally assembled with three types of stable structural units C3B2H4 with ptC, CB4H2 with ptC, and CB5H2 with ppC as well as linking elements—CHCH—.On the basis of calculation results the bonding features, spectroscopic properties, and the aromaticities of these novel boron-carbon compounds were discussed.Results show that as for the lowest-energy compounds contained ptC and ppC without being limited by symmetrical planes, stereo cis-structures of C2v symmetry are more stable than the corresponding planar trans-structures.Calculated nucleus-independent chemical shift (NICS) values show that the aromaticity of the center of the three-membered rings is the strongest.The total Wiberg bond indices (WBIs) of the ptC and ppC atoms of the most stable structures of the boron-carbon compounds indicate that the ptC and ppC obey the octal rule.supportedbytheExcellentSciencePre-researchProjectofShaanxiNormalUniversity(China)in2008---
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