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Composite Quantile Estimation in Partial Functional Linear Regression Model Based on Polynomial Spline

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Acta Mathematica Sinica,English Series 2021年第10期37卷 1627-1644页

作者： Ping YU Ting LI Zhong Yi ZHU Jian hong SHI School of Mathematics and Computer Science Shanxi Normal UniversityLinfen 041000P.R.China School of Statistics and Management Shanghai University of Finance and EconomicsShanghai 200433P.R.China Department of Statistics Fudan UniversityShanghai 200433P.R.China

In this paper,we consider composite quantile regression for partial functional linear regression model with polynomial spline *** some mild conditions,the convergence rates of the estimators and mean squared prediction error,and asymptotic normality of parameter vector are *** studies demonstrate that the proposed new estimation method is robust and works much better than the least-squares based method when there are outliers in the dataset or the random error follows heavy-tailed ***,we apply the proposed methodology to a spectroscopic data sets to illustrate its usefulness in practice.

关键词： Asymptotic normality composite quantile regression functional data analysis polynomial spline rates of convergence

Difluoroalkylation/lactonization of Alkenes with BrCF_(2)CO_(2)K via Photoredox Catalysis:Access toα,α-Difluoro-γ-lactones

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Chinese Journal of Chemistry 2023年第21期41卷 2819-2824页

作者： Min Zhang Qiang Li Jin-hong Lin Ji-Chang Xiao Key laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai200032 China Department of Chemistry Innovative Drug Research CenterShanghai UniversityShanghai200444 China

Due to its unique electronic properties,the difluoromethylene group(CF2)has served as a valuable unity in the design of biologically active ***γ-lactones display a broad range of biological properties,α,α-difluoro-γ-lactones may exhibit unexpected biological activities,and thus their synthesis has received increasing *** synthetic methods suffer from tedious multi-step processes,and very few effective methods have been reported ***,we describe the difunctionalization of alkenes with BrCF_(2)CO_(2)K under photoredox catalysis with the use of a boron-Lewis acid for the access toα,α-difluoro-γ-*** this transformation,the alkene substrates and the used reagents,including BrCF_(2)CO_(2)K and the boron-Lewis acid,PhB(OH)2 or BF3·THF,are cheap and widely *** efficiency and atom economy may make this protocol attractive.

关键词： Photoredox Catalysis Fluorine lactones Alkenes

Skeleton Marching-based Parallel Vascular Geometry Reconstruction Using Implicit Functions

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International Journal of Automation and computing 2020年第1期17卷 30-43页

作者： Quan Qi Qing-De Li Yongqiang Cheng Qing-Qi hong College of Information Science and Technology Shihezi UniversityShihezi 832003China Department of Computer Science and Technology University of HullHull HU67RXUK Software School Xiamen UniversityXiamen 361005China

Fast high-precision patient-specific vascular tissue and geometric structure reconstruction is an essential task for vascular tissue engineering and computer-aided minimally invasive vascular disease diagnosis and *** this paper,we present an effective vascular geometry reconstruction technique by representing a highly complicated geometric structure of a vascular system as an implicit *** implicit geometric modelling,we are able to reduce the complexity and level of difficulty of this geometric reconstruction task and turn it into a parallel process of reconstructing a set of simple short tubular-like vascular sections,thanks to the easy-blending nature of implicit geometries on combining implicitly modelled geometric *** basic idea behind our technique is to consider this extremely difficult task as a process of team exploration of an unknown environment like a *** on this idea,we developed a parallel vascular modelling technique,called Skeleton Marching,for fast vascular geometric *** the proposed technique,we first extract the vascular skeleton system from a given volumetric medical image.A set of sub-regions of a volumetric image containing a vascular segment is then identified by marching along the extracted skeleton tree.A localised segmentation method is then applied to each of these sub-image blocks to extract a point cloud from the surface of the short simple blood vessel segment contained in the image *** small point clouds are then fitted with a set of implicit surfaces in a parallel manner.A high-precision geometric vascular tree is then reconstructed by blending together these simple tubular-shaped implicit surfaces using the shape-preserving blending *** results show the time required for reconstructing a vascular system can be greatly reduced by the proposed parallel technique.

关键词： Vascular geometric reconstruction implicit modelling parallel computing high-performance high-accuracy

Fertile island effect in the sedimentary process of Tetraena mongolica Maxim nebkhas in steppe–desert ecotones on the Inner Mongolia Plateau,China

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Journal of Mountain Science 2022年第10期19卷 2791-2805页

作者： ZHAI Bo DANG Xiao-hong LIU Xiang-jie WANG Ji College of Desert Science and Engineering Inner Mongolia Agricultural UniversityHohhot 010018China Desert Forestry Experimental Center Chinese Academy of ForestryDeng kou 015200China National Positioning Observation Research Station of Hangjin Desert Ecosystem Ordos 017400China

Phytogenic mounds(nebkhas)formed by shrubs are a common phenomenon in arid and semiarid *** formation of nebkhas is accompanied by the appearance of the fertile island *** evaluation of the shrub sand compost island effect is a key link in preventing soil erosion and nutrient *** study took the typical shrub Tetraena mongolica in desert areas as the research object and quantified the sand-trapping capacity of the *** revealed the influence of sediment texture and volumetric soil water content on fertile islands during the development of *** *** results showed that(1)the single shrub intercepted large amounts of sediments due to the high density of branches of ***,forming nebkhas that were positively correlated with the shrub size.(2)The overall soil nutrient content below the shrub was greater than the soil nutrient content outside the shrub,forming a typical fertile island *** soil organic carbon(SOC),alkaline hydrolytic nitrogen(AHN),available phosphorus(AP),and available K(AK)content all increased gradually with increasing nebkha *** with the deep soil of nebkhas,the nutrient content of the surface soil was generally higher.(3)There was a positive correlation between the volumetric water content and nutrient content in nebkhas.(4)The semi-ellipsoid shape of *** enabled it to intercept large amounts of coarse-grained *** sand(100–250μm)was the main particle size in the sediment aggregates inside the *** fine sand content generally increased with increasing shrub *** analysis(RDA)revealed that the fine sand content of the nebkha sediments had a strong positive correlation with the soil nutrient *** paper provides an example for evaluating the fertile island effect during the deposition process of nebkhas in the desert transition zone.

关键词： Nebkhas Sediments Particle-size distribution Fertile island Tetraena mongolica Ordos Plateau

Metal-organic frameworks and their derivatives for Li-air batteries

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Chinese Chemical Letters 2020年第3期31卷 635-642页

作者： Yu Dong Siwu Li Shanshan hong Lu Wang Bo Wang Beijing Key laboratory of Photoelectronic/Electrophotonic Conversion Materials Key Laboratory of Cluster ScienceMinistry of EducationSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

Metal-organic frameworks(MOFs)are a class of outstanding materials in Li-air batteries because of their high surface areas,tailorable pore sizes and diverse catalytic ***,MOF-based batteries are facing challenges such as poor electronic conductivity and inferior long-cycle stability that limit their further *** review first summarizes the progress of pristine MOFs and MOF-derived materials in Li-air batteries in the past 5 years,then provides a perspective for subsequent development of MOFs and their derivatives in this emerging field.

关键词： Metal-organic frameworks MOF-derived materials Li-air batteries Li-O2 batteries Li-CO2 batteries

Protocol Format Extraction Based on an Improved CFSM Algorithm

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China Communications 2020年第11期17卷 156-180页

作者： Peihong Lin Zheng hong Lifa Wu Yihao Li Zhenji Zhou Army Engineering University Nanjing 210000China Nanjing University of Posts and Telecommunications Nanjing 210000China

As the information technology rapidly develops,many network applications appear and their communication protocols are *** many protocol keyword recognition based protocol reverse engineering methods have been proposed,most of the keyword recognition algorithms are time *** paper firstly uses the traffic clustering method F-DBSCAN to cluster the unknown protocol *** an improved CFSM(Closed Frequent Sequence Mining)algorithm is used to mine closed frequent sequences from the messages and identify protocol ***,CFGM(Closed Frequent Group Mining)algorithm is proposed to explore the parallel,sequential and hierarchical relations between the protocol keywords and obtain accurate protocol message *** results show that the proposed protocol formats extraction method is better than Apriori algorithm and Sequence alignment algorithm in terms of time complexity and it can achieve high keyword recognition ***,based on the relations between the keywords,the method can obtain accurate protocol *** with the protocol formats obtained from the existing methods,our protocol format can better grasp the overall structure of target protocols and the results perform better in the application of protocol reverse engineering such as fuzzing test.

关键词： flow clustering CFSM algorithm closed frequent sequences keyword recognition CFGM algorithm keyword relations format categorization

Robust and high-speed rotation control in optical tweezers by using polarization synthesis based on heterodyne interference

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Opto-Electronic Advances 2020年第8期3卷 23-29页

作者： Wei Liu Dashan Dong hong Yang Qihuang Gong Kebin Shi State Key laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Peking University Yangtze Delta Institute of Optoelectronics Nantong 226010China

The rotation control of particles in optical tweezers is often subject to the spin or orbit angular momentum induced optical torque,which is susceptible to the mechanical and morphological properties of individual *** we report on a robust and high-speed rotation control in optical tweezers by using a novel linear polarization synthesis based on optical heterodyne interference between two circularly polarized lights with opposite *** synthesized linear polarization can be rotated in a hopping-free scheme at arbitrary speed determined electronically by the heterodyne frequency between two laser *** experimental demonstration of a trapped vaterite particle in water shows that the precisely controlled rotation frequency of 300 Hz can be *** proposed method will find promising applications in optically driven micro-gears,fluidic pumps and rotational micro-rheology.

关键词： polarization modulation optical heterodyne optical tweezers optical rotation

Synthesis and characterization of star-comb polybutadiene and poly(ethylene-co-butene)

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Chinese Chemical Letters 2010年第3期21卷 361-364页

作者： Zhang, hong Xia Li, Yang Zhang, Chun Qing Hu, Yan Ming Wang, Yu Rong Ma, hong Wei Li, Wei Dalian Univ Technol Sch Chem Engn Dept Polymer Sci & Engn State Key Lab Fine Chem Dalian 116012 Peoples R China

A novel star-comb polybutadiene(SC-PB) was synthesized with n-butyllithium(n-BuLi) as initiator,epoxidized star liquid polybutadiene(ESPB) as coupling agent,cyclohexane as solvent by living anionic polymerization and grafting-onto technology. The SC-PB was subsequently hydrogenated by homogeneous catalysis(catalytic hydrogenation using nickel naphthenate/ triisobutyl aluminum),to transform the SC-PB into the corresponding star-comb poly(ethylene-co-butene)(SC-PEB).The SC-PB was characterized by SEC-TALLS,~1...

关键词： Anionic polymerization Grafting reaction Epoxy group Star-comb polymer Hydrogenation

Insight into SO_(2) poisoning and regeneration of one-pot synthesized Cu-SSZ-13 catalyst for selective reduction of NO_(x) by NH_(3)

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Chinese Journal of Chemical Engineering 2022年第6期35卷 184-193页

作者： Xin Yong hong Chen Huawang Zhao Miao Wei Yingnan Zhao Yongdan Li School of Environmental Engineering Tianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin Key Laboratory of Applied Catalysis Science and TechnologyState Key Laboratory of Chemical Engineering(Tianjin University)School of Chemical EngineeringTianjin UniversityTianjin 300072China Department of Chemical and Metallurgical Engineering School of Chemical EngineeringAalto UniversityEspoo 02150Finland

The effects of SO_(2) on an one-pot synthesized Cu-SSZ-13 catalyst for selective reduction of NO_(x) by NH_(3) were *** addition of SO_(2) inhibited NO_(x) conversion significantly below 300℃,while no effect on NO_(x) conversion was observed above 300℃.TGA,TPD,and XPS results showed that the deactivation was caused by the formation of(NH4)2SO_(4),SO_(2) chemisorption on the isolated Cu^(2+)ion sites,as well as the formation of CuSO_(4)-like *** them,the site-blocking effect of(NH_(4))_(2)SO_(4) on Cu^(2+)was the primary reason for ***,89%of deNO_(x) activity of the poisoned catalyst was recovered after thermal treatment at 500℃ in air,where(NH_(4))_(2)SO_(4) was completely *** activity was further recovered with regeneration temperature increasing to 600℃,removing the adsorbed SO_(2) on the Cu^(2+)*** regeneration at 600℃ could not recover the activity completely,because of the high stability of CuSO_(4)-like species.

关键词： Emission control SCR One-pot synthesis of Cu-SSZ-13 SO_(2)poisoning Activity regeneration