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Determination of triazine herbicide residues in water samples by on-line sweeping concentration in micellar electrokinetic chromatography

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Chinese Chemical Letters 2008年第12期19卷 1487-1490页

作者： Shuai Hua Zhang Yuan Yuan yang dan dan Han Chun Wang Xin Zhou Xiao Huan Zang Zhi Wang Key Laboratory of Bioinorganic Chemistry College of Sciences Agricultural University of Hebei Baoding 071001 China

A new method for the determination of atrazine, simazine and prometryn in water samples by on-line sweeping concentration technique in micellar electrokinetic chromatography （MEKC） was developed. Various parameters affecting sample enrichment and separation efficiency were systematically studied. Compared with the conventional MEKC method, up to 60-200-fold improvement in concentration sensitivity was achieved in terms of peak height by using this sweeping injection technique. The compound strychnine was used as the internal standard for the improvement of the experimental reproducibility. The limits of detection （S/ N = 3：1） for atrazine, simazine and prometryn were 9, 10 and 0.5 ng mL-1, respectively. This method has been successfully applied to the analysis of atrazine, simazine and prometryn in lake, steam and ground water.

关键词： Triazine herbicides On-line concentration MEKC Sweeping Water samples

Effects of Elevated Ozone Concentration on Starch and Starch Synthesis Enzymes of yangmai 16 Under Fully Open-Air Field Conditions

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Journal of Integrative Agriculture 2013年第12期12卷 2157-2163页

作者： ZHANG Ru-biao HU Hai-juan ZHAO Zheng yang dan-dan ZHU Xin-kai GUO Wen-shan ZHU Jian-guo Kazuhiko Kobayashi Key Lab of Crop Genetics and Physiology Jiangsu Province/Wheat Research InstituteYangzhou University State Key Laboratory of Soil and Sustainable Agriculture Ministry of Science and Technology/Institute of Soil SciencesChinese Academy of Sciences Graduate School of Agricultural and Life Sciences The University of Tokyo

O3 is not only greenhouse gas but also a primary gaseous contaminant in the *** has long-lasting effects on crop growth,yield and quality,and brings a series of ecological and environmental problems.A free-air controlled enrichment（FACE） system was applied to study the effect of elevated ozone concentration on activities of key enzymes of starch synthesis of yangmai 16 in *** main-plot treatment had two levels of O 3 ：ambient level（A-O 3） and 50% higher than ambient level（E-O 3）.The main results were that accumulation rate of amylose,amylopectin and starch were represented in a single peak curve,and their content and accumulation amount rose *** O 3 elevation decreased the accumulation rate of amylose,amylopectin and starch amylase,reduced the accumulation amount of amylopectin and starch,and decreased the content of amylopectin and starch,but increased the content of *** the increase of O 3 concentration,the enzyme activity of grain granule-bound starch synthase（GBSS）,soluble starch synthase（SSS） and starch branching enzyme（SBE） decreased after *** activities of GBSS and SSS had highly significant correlations with amylose,amylopectin and starch accumulation rate,and the activity of SBE had significant correlations with these *** the O 3 elevation decreased the activity of key enzymes of starch synthesis,which led to the variation of starch synthesis.

关键词： O3 FACE wheat starch activity of enzymes

基于Fibonacci搜索方法的航空发动机性能寻优

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航空动力学报 2016年第6期31卷 1441-1449页

作者：杨旦旦中国航空工业集团公司中国燃气涡轮研究院成都610500

介绍了Fibonacci搜索方法应用于发动机性能优化中的原理,建立带两个出口面积、气流马赫数可变的引射器的涡喷发动机的总体性能计算模型,应用Fibonacci搜索方法在优化参数区间内对该发动机进行了最大推力、最低油耗、最低涡轮前温度模式... 详细信息

介绍了Fibonacci搜索方法应用于发动机性能优化中的原理,建立带两个出口面积、气流马赫数可变的引射器的涡喷发动机的总体性能计算模型,应用Fibonacci搜索方法在优化参数区间内对该发动机进行了最大推力、最低油耗、最低涡轮前温度模式的寻优.举例说明了Fibonacci搜索方法应用的具体过程.给出了不同高度、马赫数下的寻优结果.结果表明:最优目标性能满足的约束边界与飞行高度、马赫数密切相关.不同的飞行高度、马赫数对应了不同的最优控制策略.但不论飞行任务如何,根据该方法进行的优化控制所获得的目标性能是最佳的.该优化方法不仅适用于该类涡喷发动机,也为其他类型航空发动机的优化控制打下一定的基础.

关键词：航空发动机引射器梯度 Fibonacci搜索方法起作用约束性能寻优

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低重环境下旋转轴对称贮箱内液体晃动研究

宇航学报 2013年第7期34卷 917-925页

作者：杨旦旦岳宝增中航工业燃气涡轮研究院成都610500 北京理工大学宇航学院北京100081

针对低重环境下旋转轴对称贮箱自由晃动和受侧向、纵向激励时的箱内液体晃动,用变分原理推导了基于低重环境下静液面形状的液体晃动的积分形式的动力学控制方程,由拉普拉斯方程得到用高斯超几何级数解析表达的速度势和波高,进而得到液... 详细信息

针对低重环境下旋转轴对称贮箱自由晃动和受侧向、纵向激励时的箱内液体晃动,用变分原理推导了基于低重环境下静液面形状的液体晃动的积分形式的动力学控制方程,由拉普拉斯方程得到用高斯超几何级数解析表达的速度势和波高,进而得到液体晃动的模态运动方程。分析了球形贮箱和Cassini贮箱内液体自由晃动基频,贮箱受侧向激励时液体晃动波高振幅、晃动对贮箱产生的晃动力和力矩、晃动的等效力学模型,以及贮箱受纵向激励时的晃动波高振幅、可能出现的参激共振问题。

关键词：低重环境变分原理高斯超几何级数晃动特性参激共振

Impact of Enterprise Ownership and Size on Registered Hematotoxicity in Benzene-exposed Workers

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Biomedical and Environmental Sciences 2018年第12期31卷 917-921页

作者： WANG Bo Shen HAN Lei yang dan dan ZHANG Juan YIN Li Hong ZHANG Meng Ying XU Kai XING Cai Hong ZHU Bao Li PU Yue Pu Key Laboratory of Environmental Medicine Engineering of Ministry of Education School of Public Health Southeast University Nanjing 210009 Jiangsu China Jiangsu Provincial Center for Disease Prevention and Control Nanjing 210000 Jiangsu China National Institute of Occupational Health and Poison Control Chinese Center for Disease Control and Prevention Beijing 100050 China Center for Global Health School of Public Health Nanjing Medical University Nanjing 210000 Jiangsu China

Benzene is a classified as ahuman carcinogen that can cause myelodysplastic syndrome and acute myelogenousleukemia;.This compound is also a potent toxin suppressing the bone ***,benzene causes serious hematological ad... 详细信息

关键词： SOE Impact of Enterprise Ownership and Size on Registered Hematotoxicity in Benzene-exposed Workers TWA

Increase in the variability of terrestrial carbon uptake in response to enhanced future ENSO modulation

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 32-38页

作者： Younong Li Li dan Jing Peng Qidong yang Fuqiang yang Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Key Laboratory of Atmospheric Environment and Processes in the Boundary Layer over the Low-Latitude Plateau Region Department of Atmospheric ScienceYunnan UniversityKunmingChina

El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air *** the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further *** investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 *** results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the *** higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in *** flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through *** occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures.

关键词： Carbon variability ENSO modulation CMIP6 models

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带单个引射器单轴涡喷发动机性能寻优

控制工程 2016年第9期23卷 1454-1461页

作者：杨旦旦杨帆中国航空工业集团公司燃气涡轮研究院成都610500

利用起作用集法将航空发动机的非线性不等式约束寻优问题转化为非线性等式约束寻优问题,利用一系列的梯度法最终将非线性等式约束寻优问题转化为低维的无约束寻优问题。针对一类带引射器的涡喷发动机,应用该方法对其加力模态和引射模态... 详细信息

利用起作用集法将航空发动机的非线性不等式约束寻优问题转化为非线性等式约束寻优问题,利用一系列的梯度法最终将非线性等式约束寻优问题转化为低维的无约束寻优问题。针对一类带引射器的涡喷发动机,应用该方法对其加力模态和引射模态分别进行了最大推力、最低油耗、最低涡轮前温度三种模式的性能寻优控制。仿真结果表明,该方法对所有工况点都有良好的收敛性,并且计算速度很快。该方法能实现增加发动机推力、降低油耗和涡轮前温度的目的。

关键词：起作用集法序列梯度法航空发动机性能寻优控制

带有非局部积分边值的Hadamard型分数阶微分包含解的终结点型存在性定理

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山东大学学报（理学版） 2018年第2期53卷 46-51页

作者：杨丹丹淮阴师范学院数学科学学院江苏淮安223300

利用多值映射的不动点定理,给出了以下带有非局部积分边值Hadamard型分数阶微分包含解的终结点型存在性定理:{Dαx(t)∈F(t,x(t)),10,1<η 详细信息

利用多值映射的不动点定理,给出了以下带有非局部积分边值Hadamard型分数阶微分包含解的终结点型存在性定理:{Dαx(t)∈F(t,x(t)),10,1<η

关键词： Hadamard型分数阶微分包含边值条件终结点定理多值映射

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“互联网+博物馆教育”的新思考

东南文化 2017年第5期 118-122页

作者：杨丹丹首都博物馆北京100045

随着"互联网+传统行业"倡导的提出,日新月异的互联网新技术开始不断地运用于博物馆的展览和建设中,拓展了博物馆服务的时间和空间,惠及民生。面对博物馆自身发生的巨大变化,博物馆教育工作也应做出相应改变,与之协调发展。博物馆学界除... 详细信息

随着"互联网+传统行业"倡导的提出,日新月异的互联网新技术开始不断地运用于博物馆的展览和建设中,拓展了博物馆服务的时间和空间,惠及民生。面对博物馆自身发生的巨大变化,博物馆教育工作也应做出相应改变,与之协调发展。博物馆学界除了关注互联网技术层面的引入和呈现,更应关注技术改变背后带来的理念和思维方式的创新。对"互联网+"形势下的博物馆教育进行必要的分析研究,意义重大。

关键词：博物馆教育职能互联网+ 融合创新