548 research outputs found

    Primary study of the electrochemical ammonia compression technology based on the fuel cells

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    氨是目前广泛使用的良好的制冷剂,具有价格低廉、压力适中、单位制冷量大、放热系数高以及流动阻力小等优点。几乎所有的食品加工的冷却设备都有用到氨,比如冷库、冰箱和空调等。氨气压缩机是空调制冷循环系统的核心部件,作为关键核心技术的压缩机技术,它的研发和创新具有举足轻重的作用。 本研究提出了一种电化学式氨气压缩技术并进行了初步探究,将常压的氢气与氨气的混合气体用电化学的方法进行压缩,得到高压的氢气与氨气的混合气体,该压缩装置类似于质子交换膜燃料电池,核心结构为膜电极。 选用Nafion117(N117)膜为阳离子交换膜,并将N117膜进行铵化处理。通过交流阻抗法测试铵化处理后的N1...Ammonia is an excellent refrigerant which has many advantages, such as low cost, moderate pressure, large unite refrigerating capacity, high coefficient of heat release and small flow resistance. Ammonia is almost used in the food processing cooling equipment, such as cold storage, refrigerator, air-conditioning and so on. The ammonia compressor is the core component of air conditioning refrigerat...学位:工学硕士院系专业:化学化工学院_化学工程学号:2062013115151

    The Study of Effects of Surface Charge on the Adhesion Behavior of Escherichia coli

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    相比于浮游生存方式,细菌更倾向于粘附在材料表面生存。细菌粘附在材料表面最终会导致生物膜的形成,对生物医疗设备、水存储及处理系统、海洋船舶和食品等研究和应用领域造成严重危害。细菌在固体表面的粘附过程十分复杂,主要受细菌自身特性、材料表面性质及环境特性等因素的影响。细菌在水溶液中通常呈电负性,因此,深入了解细菌与不同带电表面的相互作用对开发抗菌材料具有重大意义。 由于氧化铟锡(Indium-Tin-Oxide,ITO)玻璃具有良好的物理性质,如在生理条件下的稳定性,良好的透明性和导电性等特点,因此ITO非常适用于研究材料表面改性对细菌粘附的影响。在本文中,我们以ITO导电玻璃为基底,制备了磺酸基...Bacteria prefer attaching to solid substrates rather than dwelling in a planktonic state, eventually leading to the formation of biofilms and surface-bound communities of microbes may cause adverse consequences in the research and application fields, e.g., biomedical devices, water storage and treatment systems, marine vessels and the food industry. The adhesion of bacteria onto solid surfaces is ...学位:工程硕士院系专业:化学化工学院_工程硕士(化学工程)学号:2062014115148

    The illness writing of the “Scar-Introspection Literature”

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    “伤痕、反思文学”作为文革结束后,新时期文学的起点,是文学界对国家苦难记忆和自身悲惨经历的书写。纵观历史,从春秋诸子百家的“国病”修辞到晚清至五四知识分子“救国强体”“疗救国民”的论说,疾病隐喻爆发的时代,往往是时代矛盾尖锐,意识形态统治开始松动的时期。刚刚从“文革”中走出的“伤痕、反思文学”正是在这样的背景下,形成了中国文化史上又一个疾病书写的“高潮”。从“伤痕文学”的总体命名以及《伤痕》、《阵痛》等小说的题目中可以看出这一时期文学中疾病书写的隐喻性、象征性。本论文以“伤痕、反思文学”中的疾病书写为研究对象,结合此前中国现代、当代文学中疾病书写的传统,运用疾病隐喻、性别研究理论,将研究视野聚...As the starting point in the new era literature after the Cultural Revolution, “Scar-Introspection Literature” was written down by the literary circles for suffering memory of the nation and their own miserable experiences. Throughout the history, which from the “disease of society” rhetoric raised by the “Hundred Schools of Thought” in the Spring and Autumn period to the “National Salvation” and...学位:文学硕士院系专业:人文学院_中国现当代文学学号:1022014115237

    『褄重思乱菊』翻刻と解題

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    Microstructures and formation mechanisms of Au on Si(111)-7×7 surfaces

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    Si作为最重要的半导体材料,其表面结构及外延生长一直是人们关注的研究课题。鉴于Au/Si界面在电子器件和表面催化等方面的广泛应用,深入了解其微观结构和特性具有重要的意义。本论文结合超高真空扫描隧道显微镜、第一性原理计算以及动力学蒙特卡罗模拟方法,对Au在Si(111)-7×7表面上的结构性质及其形成机制进行了系统的研究。 首先,针对Au原子在Si(111)-7×7表面的吸附形态,我们采用扫描隧道显微镜进行观测,结果显示室温下快速扩散的Au原子在78K低温下表现为7×7半单胞内的单个亮点。我们采用第一性原理计算方法,比较分析了不同吸附模型的能量稳定性和电子结构,并进行STM图像模拟,确定了Au...As one of the most important semiconductor materials, the surface structures and epitaxial growth of Si have been attracting attention. It is significant to characterize and understand the microstructures of Au/Si interface due to its wide application in the electronic devices and surface catalytic engineering. By combining the ultrahigh vacuum scanning tunneling microscopy, first-principles calcu...学位:理学博士院系专业:物理与机电工程学院物理学系_凝聚态物理学号:B20042401

    A Research on W Company's Resource Allocation by Goal Programming

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    近年来电子商务在生活消费、金融服务、跨境贸易等各个领域强势崛起,越来越多电商团队的成立使得市场竞争趋近白热化。有些企业想通过超低价策略占领市场,然而这种做法不仅使企业自身陷入现金流危机,也大幅降低了行业利润。如何确立经营重点,如何合理有效的分配资源,是经营者需要认真探讨的重要问题。本论文研究的W网店资源配置问题,旨在使用目标规划、因子分析等定量分析工具,为W网店提供一个客观的、可操作性强的资源配置分析模型,给经营决策提供科学有效的参考方案。文中首先介绍了W网店所处的行业背景与发展现状;其次从资金、商品、人力等方面分析了W网店在资源配置上存在的问题;再次采用因子分析法对日常关注的经营指标进行降维...During the past few years, Electronic Commerce has experienced a sharp rising in the fields of living consumption, financial services and cross-border trade. More and more e-commerce teams have been establishing, make domestic e-commerce markets more competitive. Some companies adopt low-price strategy to survive in the market. However, the price wars bring serious negative effects. On the one han...学位:工程管理硕士院系专业:管理学院_工商管理硕士(工商管理硕士)学号:1792013115105

    Research on Linkage of Enterprises’ Achievement Evaluation and Salary for Operators Based on BSC ——Taking M Company as an example

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    企业业绩评价是企业管理的基本前提,同时,企业业绩评价必须与激励机制相结合,才能有效地实现企业发展的战略目标。经营者是企业中最稀缺的资源,对经营者的激励是企业中最重要的激励。因此,如何全面、公允地评价企业业绩,并将经营者的薪酬与企业业绩科学有效地挂钩,已成为促进企业改革发展的一个重要问题。 首先,本文以高新技术企业M公司为案例背景,从分析该公司业绩评价和经营者薪酬制度中存在的问题为研究出发点,介绍了本文的研究背景,回顾了中外关于企业业绩评价理论与方法的变革过程,并指出了平衡计分卡为企业业绩评价指标体系的创新作出的重要贡献。其次,分析和探讨了BSC的理论基础和对于高新技术企业的实践意义。然后,本...Achievement evaluation is the basic premise of enterprise management; meanwhile, strategic objectives of the development of enterprises can only be effectively realized by combining the achievements evaluation and encouragement mechanisms. Operators are the scarcest resources of enterprises, so encouragement for the operators are the most important one in enterprises. How to roundly and fairly eva...学位:会计硕士院系专业:管理学院会计系_会计硕士(MPACC)学号:X200515701

    A Study of Xiamen Library in Modern Times In the View of Reading History

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    图书馆是中国近代化的产物,如何理解图书馆在中国近代社会的产生、发展与演变是中国近代历史研究的重要课题。特别是图书馆作为联系读者和书籍之阅读行为发生的场地,在构建地域社会的国家认同和促进大众文化的发展中起到了重要作用。本文选取厦门图书馆为研究对象,将其置于传统处在文化边缘、近代又得风气之先的厦门地方社会史脉络中,对相关问题作初步考察。全文除绪论和结论外,共分三章: 第一章讨论清代厦门的公共藏书与社会阅读。通过分析分别处于新旧之际的传统书院和博闻书院的藏书类型与功能,理清从清代到近代前期,厦门书院藏书形态的变化,以期展示厦门图书馆与早期书院的传承与裂变。 第二章讨论民初图书馆与厦门士人的关系。...The library was a product of modernization in China, so how to understand the emergence, development and evolution of the library is an important research subject in modern history of China. Particularly, as a site of linking the readers and books, the library played an important role in building national identity and promoting the development of popular culture in modern China. By making it in th...学位:历史学硕士院系专业:人文学院历史学系_中国近现代史学号:1032007115162
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