61,684 research outputs found

    Using the generalized interpolation material point method for fluid-solid interactions induced by surface tension

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    This thesis is devoted to the development of new, Generalized Interpolation Material Point Method (GIMP)-based algorithms for handling surface tension and contact (wetting) in fluid-solid interaction (FSI) problems at small scales. In these problems, surface tension becomes so dominant that its influence on both fluids and solids must be considered. Since analytical solutions for most engineering problems are usually unavailable, numerical methods are needed to describe and predict complicated time-dependent states in the solid and fluid involved due to surface tension effects. Traditional computational methods for handling fluid-solid interactions may not be effective due to their weakness in solving large-deformation problems and the complicated coupling of two different types of computational frameworks: one for solid, and the other for fluid. On the contrary, GIMP, a mesh-free algorithm for solid mechanics problems, is numerically effective in handling problems involving large deformations and fracture. Here we extend the capability of GIMP to handle fluid dynamics problems with surface tension, and to develop a new contact algorithm to deal with the wetting boundary conditions that include the modeling of contact angle and slip near the triple points where the three phases -- fluid, solid, and vapor -- meet. The error of the new GIMP algorithm for FSI problems at small scales, as verified by various benchmark problems, generally falls within the 5% range. In this thesis, we have successfully extended the capability of GIMP for handling FSI problems under surface tension in a one-solver numerical framework, a unique and innovative approach.Chapter 1. Introduction -- Chapter 2. Using the generalized interpolation material point method for fluid dynamics at low reynolds numbers -- Chapter 3. On the modeling of surface tension and its applications by the generalized interpolation material point method -- Chapter 4. Using the generalized interpolation material point method for fluid-solid interactions induced by surface tension -- Chapter 5. Conclusions

    Methotrexate Nanoparticles: Synthesis, Characterization, and in Vitro and in Vivo Antitumoral Activity

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    癌症纳米疗法的迅速发展,解决了传统药物递送系统的选择性低、毒性大和耐药性等问题。研究高效的纳米靶向制剂是解决这些问题的关键课题,已受到生物医学及材料科学研究者的极大关注和兴趣。而肿瘤生长分子机制的揭示,发现肿瘤细胞与正常细胞的结构差异性,使得肿瘤细胞特有的分子靶点成为抗肿瘤药物研究和开发的热点。 本论文以提高药物的靶向性和延长其在血液中的循环时间为研究目的,制备了以壳聚糖(Chitosan,CS)和甲氧基聚乙二醇(Methoxypolyethyleneglycol,mPEG)为载体的甲氨蝶呤(Methotrexate,MTX))纳米靶向缓释系统,并研究其在体内外抗肿瘤作用。首先,对该MTX纳...Cancer nanotherapeutics are rapidly progressing and being put in place to solve several limitations of conventional drug delivery systems. With the rapid development of materials science, cell biology and molecular biology, targeted agents have grown up to be an important research content on the field of biomedical. Furthermore, as the revealing of the molecular mechanism of tumor growth, which th...学位:工学博士院系专业:材料学院_材料物理与化学学号:2072012015330

    Material Design of Food Culture in A Dream of Red Mansions for Learners in Middle and Advanced Level

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    中国文化博大精深、源远流长,是中华民族立足之根本。对外汉语教学中必须有文化教学已经是对外汉语教学界公认的观点。海内外汉语教学中也已经有诸多文化教学方面的尝试。然而大多数文化教学内容较为单一。目前对外汉语教学中介绍中国文化的形式大致可分为专门编写的中国文化的概述教材或者在语言课本中出现的文化点,很少有将中国经典文学作品作为对外汉语教材的。《红楼梦》作为中国古典四大名著之首,具有高度审美价值和文化价值。《红楼梦》中写到了中国文化的方方面面,其中饮食文化是独具特色的一方面。饮食文化也是中国文化中具有代表性的一方面。因此,笔者尝试针对中高级汉语学习者,将《红楼梦》饮食文化内容作为对外汉语教材来传播优秀...Chinese Culture is profound and has a long history. The eating habits and literatures are the elementary components of Chinese culture. Though not a monograph specialized in food culture, A dream of Red Mansions is an outstanding literature works with a large number of text descriptions on China’s food culture, and which makes it even precious. The works well integrated food culture into the story...学位:汉语国际教育硕士院系专业:海外教育学院_汉语国际教育硕士学号:2652012115123

    The Design and Implementation of Graded Fund Arbitrage Trading Assistant System

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    随着我国资本市场的迅速发展,在沪、深两个交易所上市的分级基金也备受投资者关注。近年来出现的分级基金,是我国资本市场的一种新鲜事物,且由于我国资本市场正处于起步与转型阶段,市场参与者知识水平与投资技能参差不齐,市场总体还远未达到有效市场的水平,因此市场中仍然存在着许多无风险或低风险的套利机会,投资者通过套利交易可以获得一定的超额利润,分级基金的套利交易就是一个例证。现有的套利交易系统由于开发、维护成本较高,只有大型机构投资者才能够负担,个人投资者或小型机构难以获取,往往只能采用人工方式进行套利交易,但人工方式套利具有效率低、失误率高、难以及时把握套利机会等固有缺陷。 本文结合当前资本市场的发展...With the continuous progress of China's capital market, graded fund listed on Shanghai, Shenzhen Stock Exchange has also attracted investors’ attention. graded fund emerging in recent years is a new thing in China's capital market. As China's capital market is in its infancy and transformation stage,the level of knowledge and investment skills of market participants are uneven.Market is far from r...学位:工程硕士院系专业:软件学院_工程硕士(软件工程)学号:X201323209

    Design and Implementation of the Base Station Software Based on Middleware

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    摘要 随着计算机技术的不断发展,目前通信软件的规模和复杂性日益增大,同样面临着应用环境动态多变、业务间耦合性、可靠性和高效性等挑战。而基站软件系统所应用的消息中间件的局限性和所存在的缺陷不能够很好的解决这些挑战。对象中间件技术是面向对象技术和分布式计算所结合的产物,也是基站系统软件向面向对象建模演进需要应用的主流技术。 本文主要阐述如何使用对象中间件技术进行基站软件系统对象建模,实现基站系统业务解耦、代码优化、可扩充性和高可靠性等要求。以基站软件平台应用对象管理框架项目为实例,对分布式对象中间件技术在基站软件系统演进中的应用进行了研究,本文的主要内容: 1、本文首先对对象管理框架进行功能...Abstract With the continuous development of computer technology, the current communications software increasing size and complexity, the same dynamic changing environment facing applications, coupling between business, challenges such as reliability and efficiency. The limitations of the base station system application software and the messaging middleware defects can not be a good solution to th...学位:工程硕士院系专业:软件学院_软件工程学号:X201323156

    Metabolic evolution of Clostridium butyricum for 1,3-propanediol production by anaerobic fermentation from raw glycerol

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    1,3-丙二醇(1,3-PD)是一种重要的化工原料,具有广泛的应用领域,最主要的用途是作为合成高分子材料的单体。发酵法生产1,3-PD以其利用可再生资源和对环境友好等优点日益受到重视,但大部分研究以纯甘油为底物,成本较高。如果以价格低廉的工业粗甘油为底物,可大大降低生产成本。 本论文以工业粗甘油为底物,利用代谢进化方法筛选能快速厌氧转化粗甘油产1,3-PD的Clostridiumbutyricum,提高1,3-PD的产量和生产强度,以降低发酵法生产1,3-PD的成本。研究内容分为三个部分:菌种代谢进化、通过发酵对比选取优势菌株、补料分批发酵过程优化。 一、通过在培养基中添加高浓度的粗甘油和...1,3-Propanediol (1,3-PD) is an important chemical compound with wide range of applications. It is mainly used as a monomer for the synthesis of various polymers. Microbial production of 1,3-PD has attracted wide attentions as it uses renewable resources and dose not generate pollutants. Most studies were done using pure glycerol and its cost is high. The cost could be reduced if raw glycerol is us...学位:工学硕士院系专业:化学化工学院_生物化工学号:2062010115149

    The Study on A Hand Book of the Chinese Language (1863) by James Summers from Morphology Perspective

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    萨默斯的《汉语手册》对汉语的词法进行了细致的研究。作者将汉语词汇按照分布及意义等标准分为名词、代词、动词、数词、形容词、副词、介词、连词等几类,并且从音节结构与构词方式等角度对各词类进行了内部分类。在他之前的汉学家,比如瓦罗(1703)、马若瑟(1728)、马士曼(1814)、马礼逊(1815)、雷慕沙(1822)、肖特(1857)以及艾约瑟(1857)等人的研究都对萨默斯的论述产生过一定的影响。但他的分类方式更为细致而科学,划分标准更为统一而合适,具有较强的逻辑性。而且他的分类与我国较早的语言学家的分类有一定的相似性,包括马建忠、杨树达、黎锦熙、高名凯、陈承泽、王力、朱德熙、吕叔湘等。同样地...“A handbook of the Chinese Language”, written by James Summers, has done a detailed study on Chinese morphology. Summers classified the Chinese words into noun, pronoun, verb, numeral, adjective, adverb, preposition, conjunction, etc., mainly according to their distributions and meanings. And then, he divided the above parts of speech into smaller categories by distinguishing their syllable struct...学位:文学硕士院系专业:人文学院_语言学及应用语言学学号:1022013115239

    Dry and Wet Deposition Characteristics and Anthropogenic Sources of Atmospheric Mercury in Xiamen

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    大气汞是危害人体健康的毒性污染物。大气中不同形态的汞具有不同的理化特性,颗粒态总汞TPM(Totalparticulatemercury)沉降速率高,能在排放源附近沉降,对区域内的生态环境造成较大的危害;大气气态总汞TGM(Totalgaseousmercury)因其具有较低的水溶性和沉降速率,可在大气中停留0.5-2年,能够进行长距离传输,被认为是全球性污染物。目前欧美地区已经广泛地建立起汞监测网络,虽然国内的大气汞监测也陆续开展起来,但是长时间持续监测尚不多见。本研究基于实验室前期的研究成果,于2014年8月至2016年2月在厦门大学思明校区及翔安校区设点监测TGM、TPM,同时利用HYS...Atmospheric mercury is a toxic pollutant concerned by human’s health. Different speciated merucry behave quiet differently, total particulate mercury(TPM) has high deposition velocity, it can deposit around emission sources by wet and dry deposition and cause regional environmental pollution. Total gaseous mercury(TGM) can transport globally and stay in the atmosphere with a residence time of 0.5-...学位:工学硕士院系专业:环境与生态学院_环境工程学号:3332013115174

    Feasibility study of utilizing multi-biomarkers in Sebastiscus marmoratus to monitor marine combined pollution

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    生物标志物检测技术具有效应快、灵敏度高和特异性强的优点,已广泛应用于细菌、寄生虫、病毒等方面的定性检测。但目前对于生物标志物的研究以室内为主,现场应用较少。许多在室内研究中与污染物有较好相关性的生物标志物在现场应用中却不甚理想。因此,将室内研究结果推广到现场检测研究具有十分重要的意义。 在复杂的海洋环境中,单一生物标志物只能从某一层面反应污染物的生物效应,建立一套多生物标志物的生物检测技术就显得尤为重要。综合生物标志物响应指数法(Integratedbiomarkerresponse,IBR)是一种基于多种生物标志物反应的综合评价生态环境健康状况的方法,具有可视化优点,能够很好地区分不同站位...Biomarker detection technology has been widely used in the qualitative detection of bacteria, parasites and virus because of its high sensitivity, specificity, convenience, efficiency. The study on biomarkers is mostly laboratory research rather than field research as far as now. Some biomarkers have a good correlation with pollutants in laboratory research, but the application of field monitoring...学位:理学硕士院系专业:环境与生态学院_环境科学学号:3332013115172

    Research on the Socialization Service System of the Reservoir Immigrants in Zhejiang Province in Terms of Later-stage Support

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    该研究根据中共中央关于建立新型农业社会化服务体系的精神,思考和关注农村水库移民这一特殊群体的社会服务体系建设问题,以浙江省的水库移民的社会服务体系为研究对象,以社会治理、社会整合、公共选择理论等为理论基础,运用了调查分析、定性定量分析、比较分析等研究方法,对浙江省水库移民后期扶持社会服务体系相关问题作了深入研究。 该研究从内容上讲,填补了该领域的空白,是水库移民后扶研究和农村社会化服务研究的结合、细化和补充。根据文献检索,关于水库移民后期扶持工作的研究和关于农村社会化服务方面的研究较为深入,但对农村水库移民这一相对特殊的群体的社会化服务研究却非常少。 浙江省作为沿海经济强省,在新农村建设和...According to the spirit of the communist party of China on establishing a new agricultural socialization service system , making the Reservoir migrants social service system in zhejiang province as the research object, using the Social governance、 social integration and public choice theory as the foundation of theory study, Using the survey analysis, qualitative quantitative analysis, comparativ...学位:公共管理硕士院系专业:公共事务学院_公共管理硕士学号:1392012115027
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