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Chemo-, site-selective reduction of nitroarenes under blue-light, catalyst-free conditions

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Chinese Chemical Letters 2022年第5期33卷 2420-2424页

作者： Bin Wang Jiawei Ma hongyuan ren Shuo Lu Jingkai Xu Yong Liang Changsheng Lu Hong Yan State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

The tandem reaction of photoinduced double hydrogen-atom transfer and deoxygenative transborylation for chemo-and site-selective reduction of nitroarenes into aryl amines under catalyst-free, room temperature conditions was disclosed in excellent yields. In this reaction, isopropanol(^(i)PrOH) was used as hydrogen donor and tetrahydroxydiboron [B_(2)(OH)_(4)] as deoxygenative reagent with green, cheap, and commercially available credentials. In particular, a wide range of reducible functional groups such as halogen(-Cl,-Br and even-I), alkenyl, alkynyl, aldehyde, ketone, carboxyl, and cyano are all tolerated. Moreover,the reaction preferentially reduces the nitro group at the electron-deficient site over another nitro group in the same molecule. A detailed mechanistic investigation in combination of experiments and theoretical calculations gave a reasonable explanation for the reaction pathway.

关键词： Nitroarenes Selective Reduction Catalyst-free Photoinduced Transborylation

Boosting genome editing in plants with single transcript unit surrogate reporter systems

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Plant Communications 2024年第6期5卷 32-43页

作者： Xu Tang Qiurong ren Xiaodan Yan Rui Zhang Li Liu Qinqin Han Xuelian Zheng Yiping Qi hongyuan Song Yong Zhang Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation Integrative Science Center of Germplasm Creation in Western China(Chongqing)Science CitySchool of Life SciencesSouthwest UniversityChongqing 400715China Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River Ministry of EducationChongqing 400715China College of Horticulture and Landscape Architecture Southwest UniversityChongqing 400715China Department of Biotechnology School of Life Sciences and TechnologyCenter for Informational BiologyUniversity of Electronic Science and Technology of ChinaChengdu 610054China School of Synbiology School of Life ScienceShanxi UniversityTaiyuan 030006China Department of Plant Science and Landscape Architecture University of MarylandCollege ParkMD 20742USA Institute for Bioscience and Biotechnology Research University of MarylandRockvilleMD 20850USA

CRISPR-Cas-based genome editing holds immense promise for advancing plant genomics and crop ***,the challenge of low editing activity complicates the identification of editing *** this study,we introduce multiple single transcript unit surrogate reporter(STU-SR)systems to enhance the selection of genome-edited *** systems use the same single guide RNAs designed for endogenous genes to edit reporter genes,establishing a direct link between reporter gene editing activity and that of endogenous *** strategies are used to restore functional reporter genes after genome editing,including efficient single-strand annealing(SSA)for homologous recombination in STUSR-SSA ***-SR-base editor systems leverage base editing to reinstate the start codon,enriching C-to-T and A-to-G base editing *** results showcase the effectiveness of these STU-SR systems in enhancing genome editing events in the monocot rice,encompassing Cas9 nuclease-based targeted mutagenesis,cytosine base editing,and adenine base *** systems exhibit compatibility with Cas9 variants,such as the PAM-less SpRY,and are shown to boost genome editing in Brassica oleracea,a dicot vegetable *** summary,we have developed highly efficient and versatile STU-SR systems for enrichment of genome-edited plants.

关键词： CRISPR-Cas9 single transcript unit STU surrogate reporter SR single strand annealing SSA cyto-sine base editing adenine base editing

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滨海新区科技型企业创新驱动发展路径研究

天津师范大学学报（社会科学版） 2014年第4期34卷 47-51页

作者：罗永泰任洪源天津财经大学天津300222

天津滨海新区科技型企业应当关注如何科学确定适合自身特点的创新驱动发展路径。路径选择应与新区产业体系、独特政策优势、转型升级要求和企业创新要素相结合。在不同发展阶段,科技型企业应选择不同要素组合主导型路径。政府部门可以... 详细信息

天津滨海新区科技型企业应当关注如何科学确定适合自身特点的创新驱动发展路径。路径选择应与新区产业体系、独特政策优势、转型升级要求和企业创新要素相结合。在不同发展阶段,科技型企业应选择不同要素组合主导型路径。政府部门可以通过加强培训辅导、强化政策聚焦、跟踪监测评估,帮助科技型企业改善路径管理。

关键词：滨海新区科技型企业创新驱动

A FAS approach for stabilization of generalized chained forms: part 1. Discontinuous control laws

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Science China(Information Sciences) 2024年第2期67卷 118-143页

作者： Guang-ren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology Center for Control Science and Technology Southern University of Science and Technology

In this paper, a type of general nonholonomic systems is proposed, which contains both the Brockett’s two example systems, and their extended n-dimensional chained forms, as special cases. For the stabilization of such systems, a stabilizing controller is proposed based on the fully actuated system(FAS)approach, which is discontinuous at the origin but time-invariant when the open-loop system is time-invariant,and drives the feasible trajectories of the system to the origin exponentially. Furthermore, the proposed FAS approach is also extended to the sub-normal system case and the time-delay system case.

关键词： nonholonomic systems feedback stabilization exponential convergence sub-fully actuated systems time-delay systems

A FAS approach for stabilization of generalized chained forms: part 2. Continuous control laws

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Science China(Information Sciences) 2024年第3期67卷 114-135页

作者： Guang-ren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and Technology

In this paper, continuous time-varying stabilizing controllers for the type of general nonholonomic systems proposed and treated in part 1 are designed using the fully actuated system(FAS) approach. The key step is to differentiate the first scalar equation, and by control of the obtained second-order scalar system, a proportional plus integral feedback form for the first control variable is obtained. With the solution to this designed second-order scalar system, the rest equations in the nonholonomic system form an independent time-varying subsystem which is then handled by the FAS approach. The overall designed controller contains an almost arbitrarily chosen design parameter, and is proven to guarantee the uniformly and globally exponential stability of the closed-loop system. The proposed approach is simple and effective,and is demonstrated with a practical example of ship control.

关键词： nonholonomic systems feedback stabilization fully actuated systems Lyapunov stability continuous controllers

Resilient control of flexible hypersonic vehicles against unmatched distributed faults

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Chinese Journal of Aeronautics 2024年第5期37卷 60-70页

作者： Dong ZHAO Wenjing ren School of Artificial Intelligence Anhui UniversityHefei 230601China Key Laboratory of System Control and Information Processing Ministry of EducationShanghai Jiao Tong UniversityShanghai 200240China School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China

This paper studies a robust fault compensation and vibration suppression problem of flexible hypersonic *** controlled plant is represented by a cascade system composed of a nonlinear Ordinary Differential Equation(ODE)and an Euler-Bernoulli Beam Equation(EBBE),in which the vibration dynamics is coupled with the rigid dynamics and suffers from distributed faults.A state differential transformation is introduced to transfer distributed faults to an EBBE boundary and a longitudinal dynamics is refined by utilizing T-S fuzzy IF-THEN rules.A novel T-S fuzzy based fault-tolerant control algorithm is developed and related stability conditions are *** robust exponential stability and well-posedness are proved by using the modified l_(0)-semigroup based Lyapunov direct approach.A simulation study on the longitudinal dynamics of flexible hypersonic vehicles effectively verifies the validity of the developed theoretical results.

关键词： Flexible hypersonic vehicles ODE-EBBE cascade Robust exponential stability Unmatched distributed fault compensation Vibration suppression

Progress in modeling and control of probe-and-drogue autonomous aerial refueling

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Chinese Journal of Aeronautics 2024年第5期37卷 6-26,I0001页

作者： Jinrui ren Quan QUAN School of Automation Xi’an University of Posts&TelecommunicationsXi'an 710072China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

By refueling aircraft while they are in flight,aerial refueling is an efficient technique to extend their endurance and *** Aerial Refueling(AAR)is anticipated to be used to complete aerial refueling for unmanned *** are three aerial refueling methods:the Probe-and-Drogue Refueling(PDR)refueling method,the flying-boom refueling method,and the boom-drogue-adapter refueling *** paper considers the PDR approach,the most challenging of the three,because the flexible hose-drogue assembly has fast dynamics and is susceptible to various kinds of winds,which makes the probe docking with the drogue *** is divided into four phases,namely the rendezvous phase,joining phase,refueling phase,and reform phase,with the refueling phase being the most *** controller design faces the greatest challenge during the docking control of the refueling phase since it calls for a high level of safety,precision,and *** a result,the modeling and control issues encountered during the refueling phase are typical and *** fundamental idea of AAR is presented in the paper first,after which the characteristics and requirements of AAR are *** progress in modeling and control techniques for the AAR’s refueling phase is then systematically ***,potential future work for high safety,precision,and efficiency requirements is examined and suggested.

关键词： Aerial refueling Probe-and-drogue refueling Docking Flight controlsystems Unmanned Aerial Vehicles

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施工隧道负离子除尘效率的主要影响因素

西南交通大学学报 2020年第1期55卷 210-217页

作者：徐世强王明山李杰胡耀洲任洪远长安大学理学院陕西西安710064 中国公路工程咨询集团有限公司华科分公司北京100195 长安大学公路学院陕西西安710064 山东省沥青路面再生技术研究中心山东济南250000

为研究施工隧道内粉尘颗粒粒径、颗粒浓度、通风风速和负离子系统工作电压、纵向安装位置对负离子系统粉尘降除效率的影响,依据调研和实测选取隧道计算参数,建立隧道及负离子系统三维模型,采用RNG k-ε双方程湍流模型,并通过动量方程附... 详细信息

为研究施工隧道内粉尘颗粒粒径、颗粒浓度、通风风速和负离子系统工作电压、纵向安装位置对负离子系统粉尘降除效率的影响,依据调研和实测选取隧道计算参数,建立隧道及负离子系统三维模型,采用RNG k-ε双方程湍流模型,并通过动量方程附加电场力源项的方法求解电流场,利用拉格朗日法求解粉尘颗粒的运动轨迹,用SIMPLE算法对颗粒运动与电场流场进行离散相和流体相相间耦合的数值模拟计算,并将模拟结果和隧道现场抽样试验结果对比分析.研究结果表明:隧道粉尘粒径越大,浓度越大,风速越低,负离子系统工作电压越高,系统纵向安装位置越偏于上风口,负离子系统除尘效率越高;两组现场抽样试验与对应数值模拟所得的除尘效率分别为41.2%、56.7%和38.2%、51.1%,误差分别为15.5%和12.9%.考虑施工隧道大空间复杂环境的影响,通过数值模拟的方法来研究负离子系统除尘效率及其与主要影响因素的关系是可行的.

关键词：隧道工程粉尘颗粒负离子数值模拟现场试验

知识资源、研发投入与企业跨境创新绩效关系研究——基于面板数据门限回归的实证分析

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管理评论 2017年第1期29卷 105-113页

作者：任洪源刘刚罗永泰天津财经大学商学院天津300222 中国人民大学商学院北京100872

本研究利用资源基础和制度理论,运用面板数据门限回归模型,检验了知识资源、研发投入与企业跨境创新绩效的关系。通过收集2003-2013年科技类跨国上市企业的跨境创新数据进行实证分析,研究发现跨国企业的境外知识资源与研发投入正向影响... 详细信息

本研究利用资源基础和制度理论,运用面板数据门限回归模型,检验了知识资源、研发投入与企业跨境创新绩效的关系。通过收集2003-2013年科技类跨国上市企业的跨境创新数据进行实证分析,研究发现跨国企业的境外知识资源与研发投入正向影响跨境创新绩效,但存在知识资源门限;制度距离对研发投入的跨境创新绩效影响有抑制作用,且显著提高了跨境创新效率的知识资源门限。本研究还分析了跨国企业在不同制度距离条件下创新资源基础间的交互影响作用,丰富了资源基础理论。同时,基于研究结论,针对提升跨国企业跨境创新水平和加强政府部门管理提出对策建议。

关键词：知识资源研发投入跨境创新绩效制度距离