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Three new ent-kaurane diterpenoids isolated from Rubus corchorifolius L.f.

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Three new ent-kaurane diterpenoids isolated from Rubus corch...

Uniform small metal nanoparticles anchored on CeO2 nanorods driven by electroless chemical deposition

第十四届全国中药和天然药物学术研讨会

作者： Yang-Wen Ou Xue-xiang Chen Min Zhang Yong cao School of Pharmacy Hunan University of Traditional Chinese Medicine College of Food Science South China Agricultural University

Chemical investigation of the plant Rubus corchorifolius L.f.,collected in Hunan province,afforded three new ent-kaurane *** structure of these new compounds were determined to be（16R）-16,17-dihydroxy-ent-kaur-2-one（1）,（16R）-16,17-dihydroxy-ent-kaur-2-one-17-O-β-D-glucoside（2）,（16R）-9β,16,17-trihydroxy-ent-kaur-2-one（3） by various spectroscopic methods.

关键词： Rubus corchorifolius L.f. ent-kaurane diterpenoids isolation and identification

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Rare Metals 2020年第7期39卷 806-814页

作者： Zheng Chen Fang-Xian cao Wei Gao Qing-Chen Dong Yong-Quan Qu MOE Key Laboratory of Interface Science and Engineering in Advanced Materials and Research Center of Advanced Materials Science and Technology Taiyuan University of TechnologyTaiyuan 030024China Center for Applied Chemical Research Frontier Institute of Science and TechnologyXi’an Jiaotong UniversityXi’an 710049China

We report a facile electroless chemical deposition(ECD)method to deposit uniform Pd nanoparticles((2.5±0.6)nm)on CeO2 nanorods(PdNPs/CeO2-ECD)through the interface redox reaction between the reduced CeO2 and *** NPs/CeO2-ECD exhibits a stronger electronic metal-support interaction(EMSI)evidenced by higher reducibility and stronger anti-sintering capability at high temperatures,compared to that prepared by the conventional impregnation *** an EMSI effect of PdNPs/CeO2-ECD significantly improves its catalytic activity in CO ***,the chlorine residue-free catalysts through ECD process avoid the deleterious effect of chlorine on CO *** ECD process can further be extended to deposit various uniform nanoscaled noble metals(Au,Ag,Pt,Ru,Rh,etc.)on CeO2,which may deliver their potentials in advanced catalysis.

关键词： Electroless chemical deposition Electronic metal-support interaction Pd/CeO2 CO oxidation

Simulation and Field Testing of Multiple Vehicles Collision Avoidance Algorithms

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IEEE/CAA Journal of Automatica Sinica 2020年第4期7卷 1045-1063页

作者： Chaoyue Zu Chao Yang Jian Wang Wenbin Gao Dongpu cao Fei-Yue Wang the College of Computer Science and Technology Jilin UniversityChangchun 130012China Jiangsu XCMG Construction Machinery Research Institute Ltd. Xuzhou 221004China the College of Computer Science and Technology Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of EducationJilin UniversityChangchun 130012 Chongqing Xibu Automobile Proving Ground Management Co.Ltd. Chongqing 404100China the State Grid JIBEI Electric Power Company Limited Management Training Center China the Advanced Vehicle Engineering Center Cranfield UniversityCranfield MK430ALUK the State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China

A global planning algorithm for intelligent vehicles is designed based on the A* algorithm, which provides intelligent vehicles with a global path towards their destinations. A distributed real-time multiple vehicle collision avoidance(MVCA)algorithm is proposed by extending the reciprocal n-body collision avoidance method. MVCA enables the intelligent vehicles to choose their destinations and control inputs independently,without needing to negotiate with each other or with the coordinator. Compared to the centralized trajectory-planning algorithm, MVCA reduces computation costs and greatly improves the robustness of the system. Because the destination of each intelligent vehicle can be regarded as private, which can be protected by MVCA, at the same time MVCA can provide a real-time trajectory planning for intelligent vehicles. Therefore,MVCA can better improve the safety of intelligent vehicles. The simulation was conducted in MATLAB, including crossroads scene simulation and circular exchange position simulation. The results show that MVCA behaves safely and reliably. The effects of latency and packet loss on MVCA are also statistically investigated through theoretically formulating broadcasting process based on one-dimensional Markov chain. The results uncover that the tolerant delay should not exceed the half of deciding cycle of trajectory planning, and shortening the sending interval could alleviate the negative effects caused by the packet loss to an extent. The cases of short delay(< 100100 ms) and low packet loss(< 5%) can bring little influence to those trajectory planning algorithms that only depend on V2 V to sense the context, but the unpredictable collision may occur if the delay and packet loss are further worsened. The MVCA was also tested by a real intelligent vehicle, the test results prove the operability of MVCA.

关键词： Collision avoidance intelligent vehicles intervehicle communication simulation testing trajectory planning

硅烷偶联剂改性玄武岩纤维的机理及其路用性能

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建筑材料学报 2017年第4期20卷 623-629页

作者：柳力刘朝晖向宇曹前长沙理工大学交通运输工程学院湖南长沙410004

针对玄武岩纤维(BF)在中国的研究现状,为提升其在沥青混合料中的加筋和增强效果,采用硅烷偶联剂(KH550)对BF进行表面处治,并研发了一套适用于KH550表面处治BF的装置;通过红外光谱、电镜扫描和X射线能谱等试验,研究了KH550表面改性BF的机... 详细信息

针对玄武岩纤维(BF)在中国的研究现状,为提升其在沥青混合料中的加筋和增强效果,采用硅烷偶联剂(KH550)对BF进行表面处治,并研发了一套适用于KH550表面处治BF的装置;通过红外光谱、电镜扫描和X射线能谱等试验,研究了KH550表面改性BF的机理,并通过耐热性、吸持沥青能力和离析分散性等试验,对改性BF的路用性能进行了研究.研究表明:KH550溶液可显著改善BF表面特性,形成具有稳定化学键的凸起,显著提升其与沥青的黏聚力;改性BF的路用性能得到了提升,有利于其在沥青混合料中性能的发挥.

关键词：道路工程硅烷偶联剂表面处治玄武岩纤维增强机理路用性能

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危机状态下管理者应急决策的一个分析框架

上海行政学院学报 2014年第2期15卷 79-84页

作者：曹蓉王淑珍西北大学西安710127

近年来,各类危机事件频发,危机状态下管理者的应急决策已成为影响应急管理成败的重要因素。本文通过梳理个体决策维度的研究文献,构建应急决策的认知-情感、受控-自动的二维分析框架,该框架包括显性知识与隐性知识、情绪能量唤醒与情绪... 详细信息

近年来,各类危机事件频发,危机状态下管理者的应急决策已成为影响应急管理成败的重要因素。本文通过梳理个体决策维度的研究文献,构建应急决策的认知-情感、受控-自动的二维分析框架,该框架包括显性知识与隐性知识、情绪能量唤醒与情绪紧张唤醒四个构成要素,显性知识和情绪紧张唤醒与理性决策相联系,隐性知识和情绪能量唤醒与直觉决策相联系,应急决策二维度的交互作用体现为认知-受控、情感-受控、认知-自动与情感-自动四种应急决策模式,其中,后两种模式是危机状态下管理者应急决策最有效的模式,应急决策的二维分析框架对管理者应急决策能力的提升具有指导意义。

关键词：危机状态应急决策显性知识隐性知识情绪能量唤醒情绪紧张唤醒

府际科技合作何以可能——基于长三角科技创新共同体的扎根理论研究

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科技进步与对策 2024年第19期41卷 24-33页

作者：张翼曹蓉孙哲西北大学公共管理学院西北大学陕西省民生保障与社会治理研究中心陕西西安710127

以长三角科技创新共同体为例,采用扎根理论构建多层级、跨区域科技创新共同体实现机制,为厘清现实语境下府际科技创新合作规律提供新阐释。研究发现:地理、组织、制度邻近性等静态要素与中央介入程度、政策协同程度等动态要素间的策略... 详细信息

以长三角科技创新共同体为例,采用扎根理论构建多层级、跨区域科技创新共同体实现机制,为厘清现实语境下府际科技创新合作规律提供新阐释。研究发现:地理、组织、制度邻近性等静态要素与中央介入程度、政策协同程度等动态要素间的策略性互动构成府际科技合作的驱动总成。任务压力、收益预期与交易成本、风险感知作为正反向驱动因素,影响各级政府参与科创共同体的现实选择。府际压力与共同体合作行动间多源流互动是政府科创合作的重要推手。根据横向协调和纵向压力强弱匹配程度,将府际科技合作生成模式划分为任务帮扶型、转移合作型、互动发展型和响应跟随型。在科技创新等高净值领域府际合作中,高层级政府在适当施加任务压力的同时也要根据横向协调强度及共同体行动的积极性,确保纵向权力介入适度、可控。

关键词：科技创新共同体地方政府合作扎根理论

Analytical Solution of Fick's Law of the TRISO-Coated Fuel Particles and Fuel Elements in Pebble-Bed High Temperature Gas-Cooled Reactors

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Chinese Physics Letters 2011年第5期28卷 8-11页

作者： cao Jian-Zhu FANG Chao SUN Li-Feng Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084

Two kinds of approaches are built to solve the fission products diffusion models(Fick's equation)based on sphere fuel particles and sphere fuel elements *** models for homogenous TRISO-coated fuel particles and fuel elements used in pebble-bed high temperature gas-cooled reactors are presented,*** analytical solution of Fick's equation for fission products diffusion in fuel particles is derived by variables *** the fuel element system,a modification of the diffusion coefficient from D to D/Гis made to characterize the difference of diffusion rates in distinct areas and it is shown that the Laplace and Hankel transformations are effective as the diffusion coefficient in Fick's equation is dependant on the radius of the fuel *** the solutions are useful for the prediction of the fission product behaviors and could be programmed in the corresponding engineering calculations.

关键词： element diffusion equation

可见光催化和电化学合成在咪唑并[1,2-a]吡啶3位碳-杂键构建中的应用

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有机化学 2021年第5期41卷 1759-1773页

作者：刘想李文刘环宇曹华广东药科大学医药化工学院广东省化妆品工程技术研究中心广东中山528458

咪唑并[1,2-a]吡啶是一类独特的含氮化合物,该类衍生物在农药、生物医药和光电材料等领域具有重要作用.近年来,合成功能性的咪唑并[1,2-a]吡啶已经成为有机化学家和药物化学家研究的热点,并且取得了巨大进展.其中,基于绿色化学导向的可... 详细信息

咪唑并[1,2-a]吡啶是一类独特的含氮化合物,该类衍生物在农药、生物医药和光电材料等领域具有重要作用.近年来,合成功能性的咪唑并[1,2-a]吡啶已经成为有机化学家和药物化学家研究的热点,并且取得了巨大进展.其中,基于绿色化学导向的可见光催化和电催化合成官能化的咪唑并[1,2-a]吡啶,已经成为合成该类化合物的强有力的工具.根据构建咪唑并[1,2-a]吡啶3位碳-杂键类型的不同,概述了近5年来可见光催化和电化学合成构建咪唑并[1,2-a]吡啶3位碳-杂键的相关研究.

关键词：咪唑并[1,2-a]吡啶可见光催化电化学碳-杂键

Dimensional Results for the Moran-Sierpinski Gasket

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Wuhan University Journal of Natural Sciences 2012年第2期17卷 93-96页

作者： cao Li HE Xinggang School of Mathematics and Statistics Wuhan UniversityWuhan 430072 Hubei China College of Mathematics and Statistics Central ChinaNormal University Wuhan 430079 Hubei China

In this paper, the dimensional results of Moran-Sierpinski gasket are considered. Moran-Sierpinski gasket has the Moran structure, which is an extension of the Sierpinski gasket by the method of Moran set. By the technique of Moran set, the Hausdorff, packing, and upper box dimensions of the Moran-Sierpinski gasket are given. The dimensional results of the Sierpinski gasket can be seen as a special case of this paper.

关键词： Sierpinski gasket Moran-Sierpinski gasket Moran set Hausdorff dimension packing dimension