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An Electrochemical Cinnamyl C—H Amination Reaction Using Carbonyl Sulfamate

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Chinese Journal of Chemistry 2019年第6期37卷 570-574页

作者： Shuai Liu jin Li Dalin Wang Feng Liu Xu Liu Yongyuan Gao dai jie Xu Cheng Institute of Chemistry and Biomedical Sciences Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNational Demonstration Center for Experimental Chemistry EducationNanjing UniversityNanjingJiangsu 210023China

An electrochemical cinnamyl C—H amination reaction in the absence of transition metal catalyst and oxidant was reported. The choice of carbonyl sulfamate as nitrogen source is the key to achieve desired chemoselectivity. A series of terminal amine derivatives are prepared using this protocol and the sulfonyl group can be removed with basic hydrolysis. The reaction is suggested to proceed via a continuous anodic oxidation, deprotonation, anodic oxidation, and intermolecular nucleophilic addition pathway, demonstrating the first example of electrochemical cinnamyl C—H amination.

关键词： electrochemistry C-H amination sulfamate catalyst free

MapReduce-based entity matching with multiple blocking functions

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Frontiers of Computer Science 2017年第5期11卷 895-911页

作者： Cheqing jin jie CHEN Huiping LIU Institute for Data Science and Engineering School of Computer Science and Software Engineering East China Normal University Shanghai 200062 China

Entity matching that aims at finding some records belonging to the same real-world objects has been studied for decades. In order to avoid verifying every pair of records in a massive data set, a common method, known as the blocking- based method, tends to select a small proportion of record pairs for verification with a far lower cost than O（n2）, where n is the size of the data set. Furthermore, executing multiple blocking functions independently is critical since much more matching records can be found in this way, so that the quality of the query result can be improved significantly. It is popular to use the MapReduce （MR） framework to improve the performance and the scalability of some compli- cated queries by running a lot of map （/reduce） tasks in parallel. However, entity matching upon the MapReduce frame- work is non-trivial due to two inevitable challenges： load balancing and pair deduplication. In this paper, we propose a novel solution, called M rEin, to handle these challenges with the support of multiple blocking functions. Although the existing work can deal with load balancing and pair deduplication respectively, it still cannot deal with both challenges at the same time. Theoretical analysis and experimental results upon real and synthetic data sets illustrate the high effectiveness and efficiency of our proposed solutions.

关键词： entity matching MapReduce load balancing,pair deduplication

Carbon Reduction Policies: A Regional Comparison of Their Contributions to CO_2 Abatement in Six Carbon Trading Pilot Schemes in China

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Atmospheric and Oceanic Science Letters 2015年第4期8卷 233-237页

作者： XIU jin-Feng CHOU jie-Ming DONG Wen-jie YANG Zhi-Yong dai Ru-Feng State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Future Earth Research Institute Beijing Normal University Zhuhai

The contributions of carbon reduction policies were evaluated and compared for six carbon trading pilot schemes in China, in four municipalities(Beijing, Shanghai, Tianjin, and Chongqing) and two provinces(Guangdong and Hubei). The carbon emissions accounting method of the Intergovernmental Panel on Climate Change was used to calculate the actual CO2 and the support vector machine model was used to predict CO2. Chinese carbon reduction policies abated CO2 in the six carbon trading pilot schemes after the comprehensive policies came into force. However, the contribution of policies to CO2 abatement varied among regions, and the effect of carbon reduction policy on municipality pilot schemes was greater than on provincial pilot schemes. The largest contribution of carbon reduction policy to CO2 abatement was 28.3%, for the pilot carbon trading scheme in Beijing, and the smallest contribution was 3.7%, for that in Hubei. It is crucial to consider "carbon leakage" and a carbon trading linking program in order to evaluate the effects of carbon reduction policies.

关键词： CO2 abatement carbon trading pilot scheme support vector machine reduction contribution

Pulsar/CNS integrated navigation based on federated UKF

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Journal of Systems Engineering and Electronics 2010年第4期21卷 675-681页

作者： jin Liu jie Ma jinwen Tian State Key Laboratory for Multi-spectral Information Processing Technologies Institue for Pattern Recognition and artifical Intelligence Huazhong University of Science and Technology Wuhan 430074 P. R. China

In order to improve the autonomous navigation capability of satellite,a pulsar/CNS（celestial navigation system） integrated navigation method based on federated unscented Kalman filter（UKF） is *** celestial navigation is a mature and stable navigation ***,its position determination performance is not satisfied due to the low accuracy of horizon *** pulsar navigation is a new navigation method,which can provide highly accurate range *** major drawback of single pulsar navigation is that the system is completely *** two methods are complementary to each other,the federated UKF is used here for fusing the navigation data from single pulsar navigation and *** to the traditional celestial navigation method and single pulsar navigation,the integrated navigation method can provide better navigation *** simulation results demonstrate the feasibility and effectiveness of the navigation method.

关键词： autonomous navigation celestial navigation system(CNS) pulsar federated unscented Kalman filter(UKF).

Constrained multi-degree reduction of rational Bézier curves using reparameterization

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1650-1656页

作者： CAI Hong-jie WANG Guo-jin Institute of Computer Images and Graphics State Key Laboratory of CAD ＆ CG Zhejiang University Hangzhou 310027 China

Applying homogeneous coordinates, we extend a newly appeared algorithm of best constrained multi-degree reduction for polynomial Bezier curves to the algorithms of constrained multi-degree reduction for rational Bezier curves. The idea is introducing two criteria, variance criterion and ratio criterion, for reparameterization of rational Bezier curves, which are used to make uniform the weights of the rational Bezier curves as accordant as possible, and then do multi-degree reduction for each component in homogeneous coordinates. Compared with the two traditional algorithms of ＂cancelling the best linear common divisor＂ and ＂shifted Chebyshev polynomial＂, the two new algorithms presented here using reparameterization have advantages of simplicity and fast computing, being able to preserve high degrees continuity at the end points of the curves, do multi-degree reduction at one time, and have good approximating effect.

关键词： Rational Bezier curves Constrained multi-degree reduction Reparameterization

CONVERGENCE RATE OF A GENERALIZED ADDITIVE SCHWARZ ALGORITHM

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Journal of Computational Mathematics 2006年第5期24卷 635-646页

作者： jin-ping Zeng Gao-jie Chen College of Mathematics and Econometrics Hunan University Changsha 410082 China

The convergence rate of a generalized additive Schwarz algorithm for solving boundary value problems of elliptic partial differential equations is studied. A quantitative analysis of the convergence rate is given for the model Dirichlet problem. It will be shown that a greater acceleration of the algorithm can be obtained by choosing the parameter suitably. Some numerical tests are also presented in this paper.

关键词： Schwarz additive algorithm Convergence rate Dirichlet problem.

A new stationary droplet evaporation model and its validation

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Chinese Journal of Aeronautics 2017年第4期30卷 1407-1416页

作者： Fang WANG jie YAO Shaofeng YANG Rui LIU jie jin Aero-engine Numerical Simulation Research Center School of Energy and Power Engineering Beihang University Beijing100083 China Co-Innovation Center for Advanced Aero-Engine Beijing 100083 China

The liquid droplet evaporation character is important for not only combustion chamber design process but also high-accuracy spray combustion simulation. In this paper, the suspended droplets＇ evaporation character was measured in a quiescent high-temperature environment by micro high-speed camera system. The gasoline and kerosene experimental results are consistent with the reference data. Methanol, common kerosene and aviation kerosene droplet evaporation characteristics, as well as their evaporation rate changing with temperature, were obtained. The evaporation rate experimental data were compared with the prediction result of Ranz-Marshall boiling temperature model（RMB）, Ranz-Marshall low-temperature model（RML）, drift flux model（DFM）, mass analogy model（MAM）, and stagnant film model（SFM）. The disparity between the experimental data and the model prediction results was mainly caused by the neglect of the natural convection effect, which was never introduced into the droplet evaporation concept. A new droplet evaporation model with consideration of natural convection buoyancy force effect was proposed in this paper. Under the experimental conditions in this paper, the calculation results of the new droplet evaporation model were agreed with the experimental data for kerosene, methanol and other fuels, with less than 20% relative deviations. The relative deviations between the new evaporation model predictions for kerosene and the experimental data from the references were within 10%.

关键词： Droplet Evaporation model Evaporation rate Kerosene Natural convection Thick exchange layer theory

The journey of nisin development in China,a natural-green food preservative

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Protein & Cell 2015年第10期6卷 709-711页

作者： jie Zhang jin Zhong Institute of Microbiology Chinese Academy of Sciences

In 2005,the project“Research and Development of Nisin”led by *** Huan was awarded the National Science&Technology Progress Prize(Second Class Prize)and China National Food Industry Association(CNFIA)Science&Technology Prize(Special Prize).Nisin is a lantibiotic(bacteriocin containing unusual amino acids)(Fig.1)mainly produced by gram-positive lactic acid

关键词： natural-green development preservative

Biomimetic Design and Optimal Swing of a Hexapod Robot Leg

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Journal of Bionic Engineering 2014年第1期11卷 26-35页

作者： jie Chen Yubin Liu jie Zhao He Zhang Hongzhe jin State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150001 P. R. China

Biological inspiration has spawned a wealth of solutions to both mechanical design and control schemes in the efforts to develop agile legged machines. This paper presents a compliant leg mechanism for a small six-legged robot, HITCR-ll, based on abstracted anatomy from insect legs. Kinematic structure, relative proportion of leg segment lengths and actuation system were analyzed in consideration of anatomical structure as well as muscle system of insect legs and desired mobility. A spring based passive compliance mechanism inspired by musculoskeletal structures of biological systems was integrated into distal segment of the leg to soften foot impact on touchdown. In addition, an efficient locomotion planner capable of generating natural movements for the legs during swing phase was proposed. The problem of leg swing was formulated as an optimal control procedure that satisfies a series of locomotion task terms while minimizing a biologically-based objective function, which was solved by a Gauss Pseudospectral Method （GPM） based numerical technique. We applied this swing generation algorithm to both a simulation platform and a robot prototype. Results show that the proposed leg structure and swing planner are able to successfully perform effective swing movements on rugged terrains.

关键词： biomimetic design legged robot optimal control biological movement principle Gauss pseudospectral method