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The Berry-Esseen bound for identically distributed random variables by Stein method

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Applied Mathematics(A Journal of Chinese Universities) 2012年第4期27卷 455-461页

作者： cai Guang-hui Department of Mathematics Zhejiang Gongshang UniversityHangzhou 310018China

In this paper, we obtain the Berry-Esseen bound for identically distributed random variables by Stein method. The results obtained generalize the results of Shao and Su （2006） and Stein （1986）.

关键词： Berry-Esseen bound Stein method exchangeable pair.

A new method in highway route design:joining circular arcs by a single C-Bézier curve with shape parameter

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 562-569页

作者： Hua-hui cai Guo-jin WANG Institute of Computer Graphics and Image Processing State Key Lab of CAD & CG Zhejiang University Hangzhou 310027 China

We constructed a single C-Bezier curve with a shape parameter for G^2 joining two circular arcs. It was shown that an S-shaped transition curve, which is able to manage a broader scope about two circle radii than the Bezier curves, has no curvature extrema, while a C-shaped transition curve has a single curvature extremum. Regarding the two kinds of curves, specific algorithms were presented in detail, strict mathematical proofs were given, and the effectiveness of the method was shown by examples This method has the following three advantages：（1） the pattern is unified; （2） the parameter able to adjust the shape of the transition curve is available; （3） the transition curve is only a single segment, and the algorithm can be formulated as a low order equation to be solved for its positive root. These advantages make the method simple and easy to implement.

关键词： Transition curve C-Bezier curve Monotone curvature Shape parameter

Paradox of voting and the trivial preference set of groupdecision making

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Chinese Science Bulletin 1998年第7期43卷 550-553页

作者： Yuda Hu hui cai Shanghai Jiao Tong Univ Dept Math Shanghai 200030 Peoples R China

The structure of the trivial preference set of group decision making is studied, and the essential characters and generating reasons of the paradox of voting are revealed.

关键词： group decision making paradox of voting one-to-one mapping trivial preference set.

Synthesis and neuroprotective properties of novel cinnamide derivatives

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Chinese Chemical Letters 2008年第10期19卷 1163-1166页

作者： Bin Wu Li Zhou hui hui cai School of Pharmacy Nanjing Medical University Nanjing 210029 China

A new series of compounds （E）-1-（4-（bis-arylmethyl）piperazin-l-yl）-3-arylprop-2-en-1-one （1a-r）, have been synthesized and their structures were confirmed by ESI-MS and 1H NMR. The preliminary pharmacological ... 详细信息

关键词： Cinnamide derivatives Synthesis Neuroprotective Edaravone

Cluster model for wave patterns of a 3D vertically vibrated granular system

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Chinese Science Bulletin 2011年第13期56卷 1340-1347页

作者： cai hui MIAO GuoQing Institute of Acoustics and Key Laboratory of Modern Acoustics of Ministry of Education Nanjing University Nanjing 210093 China

Based on the cluster model for wave-like motions of a 2D vertically vibrated granular system we established previously (Chin Phys Lett,2010,27:124501),a generalization of the cluster model for a 3D granular system is presented in this *** 3D cluster model proposes frustums of pyramids as clusters of the 3D granular system,and explains wave patterns as the result of the cluster-boundary and cluster-plate *** analyzing the movement of one cluster in a collision period,we derive a basic equation,which relates the internal characteristic parameter to the external driving *** theoretical results reproduce the behaviors of wave patterns as changes in the driving parameters,and the 3D dispersion relation,which agree with the experimental results.

关键词：三维模型颗粒系统垂直振动集群波模板块碰撞驱动参数特征参数

N-Heterocyclic carbene-catalyzed enantioselective(dynamic) kinetic resolutions and desymmetrizations

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Science China Chemistry 2024年第2期67卷 482-511页

作者： Yi Zhang hui cai Xiuhai Gan Zhichao Jin National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityHuaxi DistrictGuiyang550025China

N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically *** content is organized according to the activation modes involved i... 详细信息

关键词： N-heterocyclic carbene kinetic resolution dynamic kinetic resolution desymmetrization organocatalysis

Interactions between Bioactive Diperoxovanadate Complexes and Imidazole: Insights into Their Solution Structures by NMR and ESI-MS

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Chinese Journal of Structural Chemistry 2004年第6期23卷 511-518页

作者： YU Xian-Yong cai Shu-hui CHEN Zhong Departments of Physics and Chemistry State Key Laboratory for Physical Chemistry of Solid SurfaceXiamen UniversityXiamen 361005China State Key Laboratory of Structural Chemistry Fuzhou 350002China

The interactions between four high bioactive diperoxovanadate complexes Kn[OV(O2)2L]mH2O (n = 1~3, m = 1~5, L = oxalate (abbr. oxa), picolinate (abbr. pic), bipyridine (abbr. bipy) and 1,10-phenanthroline (abbr. phen); their corresponding complexes abbreviated as bpV(oxa), bpV(pic), bpV(bipy) and bpV(phen), respectively) and imidazole (abbr. imi) in solution were studied by several NMR techniques: multinuclear (1H, 13C and 51V) and variable temperature 51V NMR. Competitive coordination interactions were observed and the order of the interaction strength of the four complexes with imidazole is as follows: bpV(oxa) > bpV(pic) > bpV(bipy) > bpV(phen), which is deeply affected by the identity of the ligands and has the same order as their inhibition effect toward bovine heart phosphotyrosyl protein phosphatase. The species [OV- (O2)2(imi)]- was formed in all cases. Both of the NMR data and equilibrium constants of the interaction systems were reported. The experimental results indicate that the species of bpV(oxa) and [OV(O2)2(imi)]- are six-coordinated, while bpV(pic), bpV(bipy) and bpV(phen) are seven- coordinated in solution. ESI-MS results support the conclusions obtained by NMR.

关键词： diperoxovanadate imidazole interaction NMR ESI-MS

Precipitation and stability of reversed austenite in 9Ni steel

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 587-595页

作者： Yue-hui Yang Qing-wu cai Di Tang hui-bin Wu Research Institute of Metallurgical Engineering University of Science and Technology Beijing Beijing 100083 China

A new method was used to analyze the factors affecting the precipitation of reversed austenite during tempering. The samples were kept at various tempering temperatures for 10 min and their length changes were recorded. Then, the precipitation of reversed austenite which led to the length reduction was shown by thermal expansion curves. The results show that the effects of process parameters on the precipitation of reversed austenite can be determined more accurately by this method than by X-ray diffraction. When the quenching and tempering process is adopted, both the lower quenching temperature and higher tempering temperature can promote the precipitation of reversed austenite during tempering; and when the quenching, lamellarizing, and tempering process is used, intercritical quenching is considered beneficial to the precipitation of reversed austenite in the subsequent tempering because of Ni segregation during holding at the intercritical temperature.

关键词： cryogenic equipment low carbon steel reversed austenite precipitation stability thermal expansion measurement

Influence of mechanical damage generated by small space debris on electrostatic discharge

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Science China Earth Sciences 2016年第3期59卷 533-539页

作者： cai Ming hui LI Hong Wei HAN Jian Wei National Space Science Center Chinese Academy of Sciences

Recent studies have indicated that hypervelocity impacts by meteoroids and space debris can induce spacecraft anomalies. However, the basic physical process through which space debris impacts cause anomalies is not entirely clear. Currently, impact-generated plasma is thought to be the primary cause of electrical spacecraft anomalies, while the effects of impact-generated mechanical damage have rarely been researched. This paper presents new evidence showing that impact-generated mechanical damage strongly influences electrostatic discharge. Hypervelocity impact experiments were conducted in a plasma drag particle accelerator, using particles with diameters of 200–500 ?m and velocities of 2–7 km/s. The impact-generated mechanical damage on a specimen surface was measured by a stereoscopic microscope and 3D Profilometer and it indicated that microscopic irregularities around the impact crater could be responsible for local electric field enhancement. Furthermore, the influence of impact-generated mechanical damage on electrostatic discharge was simulated in an inverted potential gradient situation. The experimental results show that the electrostatic discharge voltage threshold was significantly reduced after the specimen was impacted by particles.

关键词： Electrostatic discharge Small space debris Inverted potential gradient Spacecraft charging