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基于图像传感器的推进剂发烟量测试方法

火炸药学报 2017年第1期40卷 98-101页

作者：王长健张克旺孙美杨燕京许毅西安交通大学电子与信息学院陕西西安710049 西安近代化学研究所燃烧与爆炸技术重点实验室陕西西安710065

提出了一种基于图像传感器的推进剂发烟量测试方法。用平行光管代替传统测试装置中的卤素钨灯,用图像传感器代替传统测试装置中的光电二极管或光敏电阻,设计了一种表面有镂空条纹的遮光罩对光源信号进行调制,采取图像数据处理方法消除... 详细信息

提出了一种基于图像传感器的推进剂发烟量测试方法。用平行光管代替传统测试装置中的卤素钨灯,用图像传感器代替传统测试装置中的光电二极管或光敏电阻,设计了一种表面有镂空条纹的遮光罩对光源信号进行调制,采取图像数据处理方法消除环境噪声对测试结果的影响。测量了SQ2推进剂、Al-CMDB推进剂和NEPE推进剂燃烧烟雾的发烟量。结果表明,SQ2推进剂和Al-CMDB推进剂的烟雾透过率曲线在点火后50s左右基本稳定;NEPE推进剂燃烧的烟雾光透过率曲线在点火50s后稳定,但有缓慢上升趋势;3种推进剂烟雾光透过率分别为84.1%、65.9%、22.3%,与传统测试方法一致。

关键词：推进剂发烟量羽流烟雾图像传感器平行光管烟雾光透过率

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高效液相色谱法测定柑橘汁中类胡萝卜素

食品科学 2006年第12期27卷 634-636页

作者：胡建中王可兴潘思轶华中农业大学食品科学技术学院湖北武汉430070

用正己烷、丙酮、乙醇混合溶剂提取宽皮柑橘大叶尾张中类胡萝卜素,10%KOH的甲醇溶液皂化12h,比较了hypersilODS2和YMCC30两种不同的色谱柱的分离效果。结果表明C30色谱柱分离效果优于hypersilODS2色谱柱。通过类胡萝卜素典型的特征吸收... 详细信息

用正己烷、丙酮、乙醇混合溶剂提取宽皮柑橘大叶尾张中类胡萝卜素,10%KOH的甲醇溶液皂化12h,比较了hypersilODS2和YMCC30两种不同的色谱柱的分离效果。结果表明C30色谱柱分离效果优于hypersilODS2色谱柱。通过类胡萝卜素典型的特征吸收峰,结合在线的PAD检测器,初步判断在C30色谱柱分离的类胡萝卜素有18种。

关键词：柑橘类胡萝卜素色素 HPLC

基于碳储量测定的低碳高效城市园林绿化建设思路探讨——以杭州西湖风景名胜区为例

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西北林学院学报 2013年第1期28卷 221-226页

作者：章银柯马婕婷王恩包志毅杭州植物园浙江杭州310013 北京林业大学北京100083 上海泛亚易道景观规划设计有限公司上海200031 浙江农林大学浙江临安311300

参考林业碳汇的方法,采用样地法、文献研究以及专家访谈等方式,对杭州西湖风景名胜区15个典型绿地的长期固碳量进行了测定分析,从而得出了一些可用于指导杭州乃至华东地区城市建设低碳高效绿地的建议,以期为今后开展低碳高效的城市园林... 详细信息

参考林业碳汇的方法,采用样地法、文献研究以及专家访谈等方式,对杭州西湖风景名胜区15个典型绿地的长期固碳量进行了测定分析,从而得出了一些可用于指导杭州乃至华东地区城市建设低碳高效绿地的建议,以期为今后开展低碳高效的城市园林绿化建设提供参考。

关键词：碳储量低碳园林绿化建设思路

Separation of nanocolloids driven by dielectrophoresis:A molecular dynamics simulation

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Science China(Technological Sciences) 2009年第7期52卷 1874-1881页

作者： NI ZhongHua ZHANG XinJie yi Hong Jiangsu key Laboratory for Design and Manufacture of Micro/Nano Biomedical Instruments School of Mechanical EngineeringSoutheast UniversityNanjing 210096China

The nonequilibrium molecular dynamics (MD) method was used to model the nanocolloids and the solvent particles. By introducing a non-uniform electric field, colloids were polarized to have opposite polarities. Separation of colloids driven by dielectrophoresis (DEP) could be seen clearly under a strong electric field at low temperatures. Analyzing the ratio of DEP velocities of colloids to thermal velocities of neutral solvent particles showed that when the ratio was correspondingly big, collision between colloids and solvent particles would be intense, making the DEP velocity of colloids fluctuate frequently. By changing the electric field strength, it was found that the enhancement of electric field strength would quicken the separation of colloids. But when the electric field strength increased to a certain degree, the separation motion would be slow because of the strong friction resistance of the solvent particles to the colloids. Moreover, studying the separation reason of colloids based on the potential energy showed that after colloids were polarized, the attractive potential energy among the colloids would be weaker than before, while the increase of temperature would reduce the attractive potential energy and increase the repulsive potential energy, which accorded with the DLVO theory.

关键词： molecular dynamics dielectrophoresis DLVO theory

Switching on/off phosphorescent or non-radiative channels by aggregation-induced quantum interference

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Aggregate

Aggregate 2024年第1期5卷 175-184页

作者： yi Kong Yu-Chen Wang Xunkun Huang WanZhen Liang yi Zhao Department of Chemistry State Key Laboratory of Physical Chemistry of Solid SurfacesiChEMFujian Provincial Key Laboratory of Theoretical and Computational Chemistryand College of Chemistry and Chemical EngineeringXiamen UniversityXiamenPeople’s Republic of China

Pure organic materials with persistent and efficient room-temperature phosphorescence have recently aroused great research interest due to their vast potential in *** crucial design principle for such materials is to suppress as much as possible the non-radiative decay of the triplet exciton while maintaining a moderate phosphorescent radiative ***,molecular engineering often exhibits similar regulation trends for the two ***,we propose that the quantum interference caused by aggregation can be utilized to control the phosphorescent and non-radiative decay *** systematically analyze various constructive and destructive transition pathways in aggregates with different molecular packing types and establish clear relationships between the luminescence characters and the signs of the singlet and triplet excitonic *** is shown that the decay channels can be flexibly switched on or off by regulating the packing type and excitonic *** importantly,an enhanced phosphorescent decay and a completely suppressed non-radiative decay can be simultaneously realized in the aggregate packed with inversion *** work lays the theoretical foundation for future experimental realization of quantum interference effects in phosphorescence.

关键词： excitonic coupling intersystem crossing organic aggregates organic room temperature phosphorescence quantum interference

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基于胜任力的公安人力资源管理模式研究

山东行政学院山东省经济管理干部学院学报 2010年第5期 34-36页

作者：张珂珂李逸群中国人民公安大学北京100038

随着所处内外环境的变化,目前公安机关所采用的基于工作分析、职位分类的公安人力资源管理固有的缺陷逐渐显现出来,需要构建新的人力资源管理模式。美国的著名心理学家麦克利兰提出的胜任力理论,为构建基于胜任力的人力资源管理模式提... 详细信息

随着所处内外环境的变化,目前公安机关所采用的基于工作分析、职位分类的公安人力资源管理固有的缺陷逐渐显现出来,需要构建新的人力资源管理模式。美国的著名心理学家麦克利兰提出的胜任力理论,为构建基于胜任力的人力资源管理模式提供了新的视角。在对胜任力理论进行简要综述的基础上,对基于胜任力的公安人力资源规划、基于胜任力的绩效管理、基于胜任力的公安人力资源培训与开发等进行了较为详细的阐述,指出了应用范围和基础,构建了一个基于胜任力的公安人力资源管理新模式。

关键词：胜任力公安人力资源绩效管理

Use of near-infrared spectroscopy and least-squares support vector machine to determine quality change of tomato juice

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第6期10卷 465-471页

作者： Li-juan XIE yi-bin yiNG College of Biosystems Engineering and Food Science Zhejiang University Hangzhou 310029 China

Near-infrared (NIR) transmittance spectroscopy combined with least-squares support vector machine (LS-SVM) was investigated to study the quality change of tomato juice during the storage. A total of 100 tomato juice samples were used. The spectrum of each tomato juice was collected twice: the first measurement was taken when the tomato juice was fresh and had not undergone any changes, and the second measurement was taken after a month. Principal component analysis (PCA) was used to examine a potential capability of separating juice before and after the storage. The soluble solid content (SSC) and pH of the juice samples were determined. The results show that changes in certain compounds between tomato juice before and after the storage period were obvious. An excellent precision was achieved by LS-SVM model compared with discriminant partial least-squares (DPLS), soft independent modeling of class analogy (SIMCA), and discriminant analysis (DA) models, with 100% of a total accuracy. It can be found that NIR spectroscopy coupled with LS-SVM, DPLS, SIMCA, and DA can be used to control the quality change of tomato juice during the storage.

关键词： Near-infrared (NIR) spectroscopy Least squares-support vector machine (LS-SVM) Quality change Tomato juice

脑皮层创伤灶注射法移植神经干细胞的实验研究

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中华创伤杂志 2007年第12期23卷 889-893页

作者：李钢徐如祥柯以铨姜晓丹南方医科大学附属珠江医院神经外科广州510282

目的观察食蟹猴自体骨髓源神经干细胞（NSCs）移植到皮层创伤灶内的存活、生长情况。方法取骨髓分离、纯化骨髓基质细胞，培养诱导成NSCs，Nestin染色阳性说明具备NSCs特征。再加入细胞标记物BrdU进行共培养7d待移植之用。移植前将BrdU... 详细信息

目的观察食蟹猴自体骨髓源神经干细胞（NSCs）移植到皮层创伤灶内的存活、生长情况。方法取骨髓分离、纯化骨髓基质细胞，培养诱导成NSCs，Nestin染色阳性说明具备NSCs特征。再加入细胞标记物BrdU进行共培养7d待移植之用。移植前将BrdU标记的NSCs收集、离心，制成干细胞悬液。食蟹猴分即时移植和延迟移植组，用微量注射针将NSCs悬液注入到猴脑皮质损伤灶及创面周边脑皮层，移植后1，3，6个月各灌杀2只食蟹猴，做移植区组织切片染色检查。结果即时移植组和延迟移植组都可观察到脑皮层创伤灶内有BrdU标记阳性细胞，而假移植组织切片中则未见BrdU阳性细胞。移植后1，3，6个月染色可见移植细胞早期呈簇状分布，移植后6个月在移植区邻近的脑白质内也可观察到有BrdU阳性细胞，正电子发射电子计算机断层扫描（PET）检查显示移植NSCs后创伤区域脑组织葡萄糖代谢有所恢复。结论移植的骨髓源性NSCs在脑内有存活，并向邻近区域迁移，有助于创伤脑组织修复。

关键词：脑损伤干细胞骨髓基质细胞细胞移植

QSPR Analysis of the Patterns Scheme Parameters for the Prediction of Monomer Reactivity Ratios

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Chinese Journal of Chemistry 2011年第1期29卷 41-47页

作者： yi, Bing Tan, Zhengde Yu, Xinliang College of Chemistry and Chemical Engineering Hunan Institute of Engineering Xiangtan Hunan 411104 China key Laboratory of Environmentally Friendly Chemistry andApplications of Ministry of Education College of Chemistry Xiangtan University Xiangtan Hunan 411105 China

Two quantitative structure-property relationship （QSPR） models were developed to correlate radical chemical structure and the reactivity parameters u and v, respectively, of the revised patterns scheme for the prediction of monomers reactivity ratios. The radicals with structure C1H3--C2HR3· （formed from C1H2=C2HR3 and Ho） were calculated using the UB3LYP density functional theory （DFF） methods with a 6-31G（d） basis set. The calculated quantum chemical descriptors were used to construct QSPR models for the reactivity parameters （u, v） by applying the genetic algorithm （GA） method, together with multiple linear regression （MLR） analysis. Correlation coeffi- cients for the training sets are 0.941 for the parameter u and 0.947 for the parameter v; correlation coefficients for the test sets are 0.947 for u and 0.934 for v. The results suggest that calculating quantum chemical descriptors from radicals to develop models for parameters u and v is feasible.

关键词： density functional calculations genetic algorithm multiple linear regression quantum chemistry,radicals structure-property relations