160 research outputs found

    Analysis on China’s Rural Finance based on the Perspective of Mechanism Design Theory

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    农业是国民经济的基础,充足的农村金融的资金供给是世界各国实现农业和农村现代化的必然路径。当前制约我国农村地区的经济发展的一个重要因素是资金不足,农村资金不足并不意味着我国农村地区缺乏资金,而是我国的农村金融制度安排不够合理引起的,主要表现在:一、农村金融体系不健全,公有制农村金融机构居多数;二、合作金融机制不健全,没有建立起真正经济学意义和国际标准的信用金融机构;三、农业发展银行政策性作用有限;四、民间金融组织缺乏规范,容易引发局部金融风险;五、农村金融主要需求主体农户和农村企业“贷款难”问题一直存在。 机制设计理论主要研究在自由选择、自愿交换、信息不完全及决策分散化的条件下,能否设计一套机...Agriculture is the foundation of a national economy, while adequate supply of rural financial capital is the necessary path for the world’s countries to achieve agricultural and rural modernization. Currently, an important factor which is restricting the economic development of China's rural areas is the scarcity of funds. The scarcity of funds in China’s rural areas does not necessarily mean that...学位:经济学硕士院系专业:经济学院经济系_西方经济学学号:1532007115151

    YAG荧光粉-无铅低软化温度玻璃复合浆料的制备与应用

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    为优化大功率白光LED的封装过程,提出将YAG荧光粉-无铅低软化温度玻璃复合浆料印刷在玻璃基片上,经热处理制备荧光玻璃片的技术方案。采用热膨胀仪、粉末衍射仪、热重分析仪、荧光光谱仪等研究无铅低软化温度玻璃成分与热学性能的关系,无铅低软化温度玻璃粉与YAG荧光粉的配比、固含量、热处理制度等因素对复合浆料及荧光玻璃片晶型、粘度及发光等性能的影响。结果表明,复合浆料固含量为70%时,粘度适用于丝网印刷;印刷后的玻璃基片在550~650℃温度下进行热处理,可制得荧光玻璃片;无铅低软化温度玻璃与YAG荧光粉质量比在1. 2~4. 0范围调整,可得到封装后色温在3500~7000 K的荧光玻璃片。该荧光玻璃片可适用于大功率白光LED的封装。华侨大学2016年实验教学改革与建设课题(66661601

    镰形棘豆黄酮类化合物对紫外线辐射引起的角质形成细胞损伤的保护作用

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    目的探讨镰形棘豆黄酮类化合物对中波紫外线照射所致人角质形成细胞损伤的保护作用。方法体外培养人角质形成细胞系,以60、90、120 mJ/cm2中波紫外线照射,加入镰形棘豆黄酮类化合物进行干预处理,倒置相差显微镜观察细胞受损程度,以MTT法检测细胞增殖活性,ELISA检测上清液TNF-α、IL-10分泌量,实时荧光定量PCR检测TNF-αmRNA、IL-10 mRNA表达。结果中波紫外线照射后,细胞形态受损,随着照射剂量增加,细胞增殖活性下降,损伤程度加重,TNF-α、IL-10分泌量增加,TNF-αmRNA、IL-10 mRNA表达水平增加。加入镰形棘豆黄酮类化合物干预后,细胞活性有所恢复,TNF-α、IL-10分泌量降低,TNF-αmRNA、IL-10 mRNA表达水平下调,具有显著性差异。结论镰形棘豆黄酮类化合物具有一定的光保护作用,抑制炎症细胞因子分泌可能是其减轻紫外线辐射损伤的机制之一

    HPLC-MS/MS间接测定类风湿关节炎患者红细胞中多聚谷氨酸化甲氨蝶呤的浓度

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    目的建立检测类风湿关节炎患者红细胞中多聚谷氨酸化甲氨蝶呤(methotrexate polyglutamates,MTXPGs)浓度的HPLC-MS/MS法。方法采用间接测定法,以同位素甲氨蝶呤-d3为内标,分别测定游离甲氨蝶呤(methotrexate,MTX)和总MTX(MTX+MTXPGs),从而计算出红细胞中MTXPGs浓度。为测定游离MTX,全血样品经反复冻融、甲醇沉淀蛋白后,经LC-MS/MS进样分析,采用电喷雾离子源(ESI)正离子模式,多反应监测(MRM)。为测定总MTX,样品(反复冻融后)与200mmol·L-1抗坏血酸37℃孵育2. 5 h,酶促MTXPGs转化为MTX,蛋白沉淀后进样分析。结果全血MTX质量浓度在1~300ng·m L-1内线性关系良好(r=0. 999 4),检测限(LOD)为0. 5 ng·m L-1,准确度(RE)在±5%内,日内和日间精密度(RSD)分别低于7. 96%和10. 88%。结论本方法快速、灵敏,具有高专属性和重现性,成功应用于临床上类风湿关节炎患者红细胞中MTXPGs浓度的监测

    Local Sensitivity and Its Stationarity Analysis for Urban Rainfall Runoff Modelling

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    基于MOrrIS筛选法,在厦门城市小流域采用8场实测降雨数据对城市降雨径流模型SWMM的水文水力模块进行局部灵敏度及其稳定性分析.结果表明,ArEA、%IMPErV和dSTOrE-IMPErV是影响降雨总径流量和流量峰值最灵敏的参数.对于总径流量,ArEA、%IMPErV和dSTOrE-IMPErV的灵敏度分别为0.46~1.0、0.61~1.0和-0.050~-5.9;而对于流量峰值,它们的灵敏度分别为0.48~0.89、0.59~0.83和0~-9.6.其中降雨强度最小的场次降雨的各个参数降雨总径流量和流量峰值的灵敏度都最大,而降雨强度较大的场次降雨的总径流量和流量峰值的灵敏度都较小.不同场次降雨模型参数的灵敏度分析具有很大的差异性,但%zErO-IMPErV对总径流量和流量峰值模拟输出影响的稳定性最小,表现在变异度最大,高达221.24%和228.10%,而COnduCTIVITy参数稳定性最大,变异系数都为0.Sensitivity analysis of urban-runoff simulation is a crucial procedure for parameter identification and uncertainty analysis.Local sensitivity analysis using Morris screening method was carried out for urban rainfall runoff modelling based on Storm Water Management Model(SWMM).The results showed that Area,% Imperv and Dstore-Imperv are the most sensitive parameters for both total runoff volume and peak flow.Concerning total runoff volume,the sensitive indices of Area,% Imperv and Dstore-Imperv were 0.46-1.0,0.61-1.0,-0.050--5.9,respectively;while with respect to peak runoff,they were 0.48-0.89,0.59-0.83,0--9.6,respectively.In comparison,the most sensitive indices(Morris) for all parameters with regard to total runoff volume and peak flow appeared in the rainfall event with least rainfall;and less sensitive indices happened in the rainfall events with heavier rainfall.Furthermore,there is considerable variability in sensitive indices for each rainfall event.% Zero-Imperv’s coefficient variations have the largest values among all parameters for total runoff volume and peak flow,namely 221.24% and 228.10%.On the contrary,the coefficient variations of conductivity among all parameters for both total runoff volume and peak flow are the smallest,namely 0.国家自然科学基金项目(50778098);福建省青年人才项目(2007F3093

    周期入力制御によるパラメータ励振系のエネルギー制御と強制引き込み現象-実機による検証-

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    In our previous work, we showed that an energy of a swing system which is a parametric excitation system can controllable by the periodic input control method. Furthermore, we demonstrated that the energy controlled swing system is a self-excited oscillation system and forced entrainment arises in that system by numerical simulation. In this paper, we describe the result verified the above results with an actual machine

    Comparative Study on Characteristics of Urban Rainfall Runoff from Two Urban Lawn Catchments in Macau and Xiamen

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    在澳门与厦门分别选一分流制管道类型的绿地小流域开展降雨径流监测,以研究城市绿地降雨径流污染特征.结果表明,两城市绿地小流域降雨径流的主要污染物为COd、TP、nO3--n,其EMC平均值分别为165.77--60.48 Mg/l、0.96--0.44 Mg/l和7.16--1.18 Mg/l;两城市绿地的COd、TP、nO3--n污染负荷平均值分别为6.53--0.63 kg/HM2、0.037 5--0.004 7 kg/HM2和0.012 2--0.012 8 kg/HM2;绿地降雨径流污染物浓度峰值出现时间早于径流量峰值;城市绿地降雨径流初始冲刷效应不明显,厦门绿地小流域降雨径流COd、TSS、TP及nO3--n的ff30分别为36.26%、26.13%、28.13%和39.03%.基于多元回归分析结果表明,总降雨量和总径流量是影响绿地降雨径流污染初始冲刷效应的主要因素.A comparative study on characteristics of stormwater runoff from two urban lawn catchments in Macau(ELH) and Xiamen(PGH) with separated sewer system were conducted.The result obtained shows that COD,TP and(NO---_3-N) are the major pollutants with mean EMC of 165.77-60.48(mg/L),0.96-0.44(mg/L) and 7.16-1.18(mg/L),respectively,and the mean values of pollutants loads of COD,TP and(NO---_3-N) from study lawn catchments are 6.53-0.63(kg/hm--2),(0.037?5)-(0.004?7)(kg/hm--2) and(0.012?2)-(0.012?8)(kg/hm--2),respectively.Peak values of major pollutant concentrations usually precede the flow peak.First flush effect of rainfall runoff from two study catchments is no obvious,which can be reflected by the low mean value of FF_(30) of TSS,COD,TP and(NO---_3-N),with 36.26%,26.13%,28.13% and 39.03%,respectively.Based on multivariate statistical analysis,first flush effect from urban lawn rainfall runoff is greatly influenced by total rainfall amount(T_r) and total runoff volume(V).国家自然科学基金项目(50778098);福建省青年人才项目(2007F3093

    HPLC法测定藏药镰形棘豆中鼠李柠檬素-3-O-β-新橙皮糖苷的含量

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    目的:建立镰形棘豆中鼠李柠檬素-3-O-β-新橙皮糖苷的含量测定方法,同时比较药材的不同部位经不同溶剂提取后所得含量。方法:采用HPLC法,色谱柱:Symmetry C18柱(4.6mm×250mm,5μm);流动相:1%乙酸水溶液-乙腈(79:21);流速:1.0mL/min;检测波长:350nm。结果:鼠李柠檬素-3-O-β-新橙皮糖苷在20-100μg/mL范围内线性关系良好(r=0.9995),平均回收率为99.49%,RSD=1.30%。溶剂对该化合物的提取率由高至低依次为甲醇,95%乙醇、水;药材叶中含量比根高。结论:本法简便、准确、重现性好,可用于该药材或相关制剂的质量控制;药材不同部位经不同溶剂提取所得含量差别较大

    Exciton-Phonon Coupling of NN_3 Center in Heavily Nitrogen Doped GaP

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    通过光致发光谱研究了在 1 9~ 4 8K范围内掺氮浓度为 0 .1 2 %时的 Ga PN的 NN3束缚激子与声子的耦合 .直接计算了 NN3束缚激子的 L O,TO和 TA声子伴线的黄昆因子 S,除了 L O声子外 ,得到了 TO和 TA声子伴线的S因子在该温度范围内对温度的依赖关系 .计算表明 ,NN3的 L O,TO和 TA声子的 S因子均与温度无关 ,说明NN3的 L O,TO和 TA声子伴线与它们的零声子线具有相同的温度依赖关系 ,符合黄昆的多声子光跃迁理论Under heavy nitrogen doping,due to the “concentration quenching” effect,the full spectrum of the NN 3 center is revealed without the interference from the spectra of other higher energy centers.This investigation offers a direct proof for that all the phonon replicas are the phonon sidebands governed by the Huang Rhys’ multiphonon optical transition theory.国家自然科学基金 (批准号 :60 2 760 0 2 );; 厦门大学预研基金 (批准号 :Y0 70 0 5 )资助项目~
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