151 research outputs found

    Spatial econometric analysis in the influence of labor flow on regional difference of China

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    改革开放以来,我国经济取得了举世瞩目的成就。然而,一方面伴随着经济的高速发展,地区之间的差距特别是东南沿海地区与其他地区的经济发展差距越来越大,而由于劳动力的流动不平衡,更扩大和加深了这种趋势。经济发展水平上的差距直接造成两大后果:一是东南沿海地区持续增长的市场空间受到明显限制,尽管它可以利用便利的水运条件拓展国际市场;二是经济落后地区收入增长持续落后,必然造成地区之间的利益冲突和其他矛盾。因此地区差距的研究成为一项重要且具有现实意义的课题。 另一方面,伴随着改革开放我国经济的日益增长,劳动力流动数量不断扩大,2004年全国发生流动人口数量达到850多万,且劳动力流动的地区分布极度不平衡,地...In the more than twenty years since the reform and open, China has achieved great development in economy. However, what has been companied with the rapid economical growth is the dramatic increase of regional differences. This difference is especially evident when comparing the economy between the southeastern districts and other parts of China. When this situation continues, two main problems wil...学位:经济学硕士院系专业:经济学院计划统计系_数量经济学学号:20041005

    The application of PCR technology in detection of SPF laboratory animal rats

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    PCR作为一项新兴技术,越来越受到人们的重视。近几年来,PCR技术不断发展,它以准确、快速、便捷等优点广泛应用在科学研究的各个领域。PCR技术应用在实验动物领域中,可提高实验动物临床检测和监测水平。笔者主要介绍PCR技术在SPF级实验动物鼠病原微生物检测中的应用。PCR as a new technology, more and more get people's attention to it in a quick, accurate and convenient advantages are widely used in scientific research fields, in recent years, the PCR technology development, and application in the field of experimental animals, greatly improving the monitoring level of experimental animals, in this paper, the PCR technology in the application of the SPF laboratory animal mouse pathogenic microorganism monitoring.福建省重点项目(2014Y0083)

    股利政策之代理成本说对我国上市公司小股东利益的损害

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    本文通过对我国特殊股权结构的剖析,并利用用友软件分红案例论证了代理成本说下的股利政策对我国小股东利益的损害,最后提出了一些解决问题的建议

    SPF级实验小鼠4种致病菌多重PCR方法的建立及优化

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    目的建立一种可同时检测4种SPF级屏障环境常见致病菌的多重PCR方法。方法本研究针对鼠伤寒沙门氏菌inv A基因、肺炎克雷伯杆菌khe基因、嗜肺巴斯德菌16SrRNA基因、铜绿假单胞菌ecf X基因序列分别设计合成特异性引物,构建可同时鉴别4种菌的多重PCR反应体系,优化后测定其特异性、灵敏性并人工模拟感染样本。结果建立的4重PCR方法能对同一样品中的4种致病菌模板进行特异性扩增,无交叉反应;对4种目的菌的检测灵敏度为10-3ng/μL;也可从混合感染的病料中特异性地检测出4种致病菌。结论本试验建立的多重PCR方法具有快速、简便、灵敏的特点,为4种致病菌的快速诊断和监控提供了有效的技术支持。福建省科技计划重点项目(No.2014Y0083

    Pervaporation Dehydration of Ethyl Acetate–Ethanol–Water Azeotrope

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    乙酸乙酯是重要的工业溶剂,直接酯化法制得的乙酸乙酯粗产品中含有乙醇和水,这三者会形成各种两元或三元共沸物。若采用萃取精馏、共沸精馏等方法进行分离,流程复杂,能耗大,成本较高。渗透汽化作为一种新型的分离技术,在共沸物系、近沸物系的分离中具有突出的优势。由于产品中乙酸乙酯含量较高,且具有良好的溶解性能,本论文采用亲水材料进行乙酸乙酯–乙醇–水三元共沸物脱水,分别以阳离子型聚合物壳聚糖(CS)和非离子型聚合物聚乙烯醇(PVA)为膜材料,通过对其进行改性,制备渗透汽化膜。利用红外光谱(FT–IR),X–射线衍射(XRD),扫描电镜(ESEM),热重分析(TG–DTG),接触角分析,密度检测等手段对膜的...Ethyl acetate is an important industrial solvent and can be produced via direct etherification. The resultant crude product containing ethanol and water will form ternary azeotropes. Azeotropic distillation and extractive distillation have been used for the purification of ethyl acetate; however, both of the two processes are suffering from high capital and operating costs because entrainers are r...学位:工学硕士院系专业:化学化工学院化学工程与生物工程系_化学工程学号:2062006115203

    Permeation and characterization of TiO_2/PVA hybrid membranes

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    通过纳米TiO2粒子填充改性制备了新型TiO2/PVA杂化膜。红外光谱表明纳米TiO2表面的羟基与聚乙烯醇(PVA)链上的羟基存在较强的氢键作用。扫描电镜显示当TiO2的质量分数低于1.5%时,在PVA中分散均匀。X射线衍射显示纳米TiO2的加入降低了膜的结晶度。通过对含水质量分数低于20%的水/乙醇体系的脱水研究了该杂化膜的渗透性能,考察了TiO2粒子填充量、料液质量分数和温度与膜分离性能之间的关系。渗透通量J随着TiO2、水质量分数和温度的升高而增加,分离因子随着温度和水质量分数的升高而下降,在TiO2质量分数为1.5%时分离因子达到最佳值。40℃下分离质量分数85%的乙醇水溶液,分离因子可达1 590,渗透通量为0.049kg/(m2.h)。Novel nanometer-sized TiO2 filled polyvinyl alcohol(PVA) membranes were prepared.Fourier transform infrared(FTIR) indicates that there is a strong hydrogen-bond interaction between PVA and TiO2.Scanning electron microscope(SEM) shows that TiO2 particles are well distributed in the membrane matrix when TiO2 mass fraction is less than 1.5%.X-ray diffraction(XRD) reveals that the crystallinity of the hybrid membrane is lower than that of the PVA membrane.The permeation properties of the membrane was studied through the dehydration of water/ethanol system,of which water mass fraction is less than 20%,and the effects of TiO2 mass fraction,feed water mass fraction and temperature on the permeation properties of the membrane were investigated.The results show that the permeation flux J increases with increasing TiO2 mass fraction,feed water mass fraction and temperature.Meanwhile,the separation factor α decreases with increasing the feed water mass fraction and temperature.Separation factor arrives at an optimal value when TiO2 mass fraction is 1.5%.The separation factor and permeation flux reach 1 590 and 0.049 kg/(m2·h) respectively for the separation of mass fraction 85% ethanol/water solution at 40 ℃.国家自然科学基金资助项目(50573063);; 教育部新世纪优秀人才支持计划资助项

    太子参环肽类化合物Pseudostellarin E对3T3-L1前脂肪细胞分化和葡萄糖吸收的作用

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    目的探讨太子参环肽类化合物Pseudostellarin E是否具有治疗2型糖尿病的潜力。方法在3T3-L1前脂肪细胞中应用了葡萄糖吸收试验和分化模型。结果 Pseudostellarin E不仅加速3T3-L1前脂肪细胞分化进程,而且在高浓度(30m M)葡萄糖条件下增加了分化的脂肪细胞对胰岛素刺激的葡萄糖的吸收。结论上述结果表明,Pseudostellarin E可能具有治疗糖尿病的潜能。国家自然科学基金面上项目(81773601);;福建省教育厅2015年第二批高等学校优秀学科(专业)带头人赴海外访学研修资助项目(闽教人[2015]103号);;福建省自然科学基金计划资助项目(2015J01065);;福建省卫生系统中青年骨干人才培养项目2015年资助计划基础项目(2015-ZQN-JC-45);;福建省厦门市科技局科技计划高校创新项目(3502Z20143026);;厦门医学院科研项目(Z2013-12,Z2013-25

    厦门市思明区老年人对医养结合养老模式的认知和参与意愿现状及其影响因素

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    目的:调查厦门市思明区老年人对医养结合养老模式的认知及参与意愿,分析其影响因素,为推进医养结合养老工作的发展提供参考。方法:采用方便抽样方法,对户籍在厦门市且居住在思明区的60周岁及以上的114名老年人进行问卷调查。结果:目前厦门市思明区老年人对医养结合养老模式的认知处于较低水平,参与意愿偏低。年龄、文化程度、子女、了解程度是影响老年人医养结合养老模式参与意愿的因素,其中文化程度、了解程度是影响参与意愿的主要因素。结论:养老机构应采取形式多样的宣传教育,提高老年人对医养结合养老模式的了解程度及参与意愿,推进医养结合养老产业的发展

    Ecosystem health assessment in decision making process of coastal zone

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    生态系统健康作为重要决策依据,能减少决策失误导致生态破坏和生态风险。但由于存在评价指标筛选难、权重难确定,评价基准操作复杂或不科学,现有综合评价方法不合理等问题,海岸带较高层次决策中系统有效的生态系统健康评价技术路线较少。本文提出基于多维决策(MddM)的生态系统健康评价技术路线能有效解决以上问题,其主要步骤包括应用所有数据评价生态系统生物成分和功能要素,专家参与生态系统健康评价以及生态与决策方案之间[影响、置信度;关系]评分,以支持决策。最后将该技术路线应用于厦门湾海岸带地区主体功能区划案例研究中。研究结果表明:厦门湾海岸带地区生态系统整体健康状况中等,从生态维度来看,更支持旅游作为厦门湾海岸带地区主体功能。The assessment of ecosystem health is important for decision-making process to avoid ecological damage and risk.There are few systematic and effective approaches of applying Ecosystem Health Assessment(EHA) into high-level decision making process because of the difficulties including indicators selecting and weighting,the complexity of establishing the reference,and lacking of integrative assessing methods.To fill this gap,a new approach of EHA based on Multi-Dimensions Decision Making(MDDM) model was developed to support high-level decision making process in coastal zone.The MDDM-based EHA approach is as follows:all collected data of ecosystem were collected to assess biological elements and ecological functions;expert judgment method was applied to assess entire ecosystem health status and to grade [Impact,Confidence;Relationship] which links ecological dimension and the alternatives of decision-making.The approach was applied in the principal function zoning in Xiamen coastal area.The results showed that the current ecosystem health status in Xiamen coastal area is mediate,and tourism should be the principal function rather than harbor transportation from the perspective of ecosystem health.国家海洋公益性科研专项课题(200905005); 2011年度“厦门大学基础创新科研基金”(中央高校基本科研业务费专项资金)项目(2011121008

    真空磁过滤电弧离子镀法制备类金刚石涂层方法及性能研究

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    采用真空磁过滤电弧离子镀方法,在GT35基体上沉积类金刚石膜。通过对清洗工艺及弧电流、工件所加负偏压、沉积温度等参数的研究,制定出了合理的工艺路线,并对这种膜层进行了X-射线光电子谱(XPS)分析,利用干涉仪、纳米硬度计对膜层的粗糙度、纳米硬度作了进一步检测。结果表明,采用此种方法制备的类金刚石膜层,SP^3含量约为40.1%;组织致密,无大的颗粒;镀膜后的粗糙度可以达到0.015μm;纳米硬度约为55GPa。并将膜层与TiN膜层组成摩擦副,进行了耐磨性试验。结果表明膜层的耐磨性较好
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