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DFT Study on Two C_4N_(12)O_4 Isomers with Pagodane- and Isopagodane-like Structures

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Chinese Journal of Structural Chemistry 2005年第11期24卷 1264-1270页

作者： LIU Feng-ling WANG jin-Shan PENG ling Department of Chemistry Shandong Normal University Jinan 250014 China

Geometries, energies, and vibrational frequencies for two C4N12O4 isomers with pagodane- and isopagodane-like structures have been calculated at the B3LYP/6-31G＊ *** 1 and 2 are of D2h and D2d symmetry, respectively. Heats of formation for the two C4N12O4 isomers have been estimated in this paper, indicating they would be reasonable candidates for high energy density materials.

关键词： two C4N12O4 isomers with pagodane-like structures high energy density material,B3LYP/6-31G* vibrational frequency heat of formation

Construction of parallel and distributed static simulation system based on augmented reality

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The Journal of China Universities of Posts and Telecommunications 2012年第4期19卷 117-121页

作者： ZHANG jin-ling School of Information Renmin University of China Beijing 100872 China

This article puts forward a kind of parallel and distributed static augmented scene system structure to improve the performance of real time augmented simulation system. Based on static registration technique, several groups of processing nodes do parallel scene pictures taking, 3D registration and virtual-real merging. Process on different nodes is controlled by uniform synchronization mechanism and network transmitting. Wide field of view image can be obtained from image mosaic operation and displayed by wide view display system. Detailed system architecture, registration algorithm, method how to determine camera position and synchronization mechanism between each process node are introduced. The experiment result can validate the good performance of the designed system.

关键词： augmented reality registration parallel and distributed structure synchronization control

A Levenberg–Marquardt Method for Solving the Tensor Split Feasibility Problem

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Journal of the Operations Research Society of China 2021年第4期9卷 797-817页

作者： Yu-Xuan jin jin-ling Zhao School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China

This paper considers the tensor split feasibility *** C and Q be non-empty closed convex set and A be a semi-symmetric *** tensor split feasibility problem is to find x∈C such that Axm−1∈*** we simply take this problem as a special case of the nonlinear split feasibility problem,then we can directly get a projection method to solve ***,applying this kind of projection method to solve the tensor split feasibility problem is not so *** we propose a Levenberg–Marquardt method to achieve higher *** analyses are conducted,and some preliminary numerical results show that the Levenberg–Marquardt method has advantage over the common projection method.

关键词： Tensor Split feasibility problem Semi-symmetric Projection Levenberg-Marquardt method

CoP@SiO2nanoreactors: A core-shell structure for efficient electrocatalytic oxygen evolution reaction

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Chinese Chemical Letters 2020年第9期31卷 2300-2304页

作者： ling jin Huan Pang School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225009China

Metallic phosphides as a crucial class of metal-like compounds show high electric conductivity and electrochemical *** is of significant benefit to understanding the relationship between the electrocatalytic performance and phosphating degree of *** this work,using Co3O4@SiO2 as precursor,core-shell structured CoP@SiO2 nanoreactors with outstanding oxygen evolution reaction performance were synthesized through a facile calcination *** electrocatalytic performance of CoP@SiO2 modified electrode that treated with 500 mg NaH2PO2 was greatly *** obtained product displays a low overpotential of 280 mV at a current density of 10 mA/cm2 and a Tafel value 89 mV/dec in alkaline *** easy available CoP@SiO2 with outstanding catalytic performance and stability possesses huge potential in future electrochemical applications.

关键词： Core-shell structure Phosphating Nanoreactors Oxygen evolution reaction Silicon shell

Photochemical decomposition of 1H,1H,2H,2H-perfluorooctane sulfonate(6:2FTS)induced by ferric ions

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Journal of Environmental Sciences 2017年第1期29卷 120-127页

作者： ling jin Chuanjia Jiang Pengyi Zhang State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniuersityBeijing 100084China.

Perfluorooctane sulfonate（PFOS） had wide applications,such as in the electroplating industry,but its use was restricted in 2009 by the Stockholm Convention,due to its environmental persistence and potential *** the most common PFOS alternative,lH,lH,2H,2H-perfluorooctane sulfonic acid（6：2FTS） and its salts have been increasingly ***,little is known about its photochemical *** paper reports the ferric ion-induced efficient decomposition and defluorination of 6：2FTS under 254 nm ultraviolet（UV） irradiation;the underlying mechanisms were also *** the presence of 100 ｜imol/L ferric ion and at pH 3.0,the first-order decomposition rate constant of 6：2FTS（10 mg/L） was 1.59/hr,which was 6 times higher than for direct UV *** effects of the ferric ion concentration and the solution pH on the 6：2FTS photodecomposition were investigated and the optimal reaction conditions were *** addition to fluoride and sulfate ions,shorter-chain PFCAs（C2-C7） were detected as major *** addition of hydrogen peroxide or oxalic acid accelerated the decomposition of 6：2FTS under UV irradiation,but not its defluorination,indicating that hydroxyl radicals can directly react with 6：2FTS but not with the shorter-chain ***,a mechanism for 6：2FTS photochemical decomposition in the presence of ferric ion was proposed,which comprises two reaction ***,hydroxyl radicals can directly attack 6：2FTS,leading to C- C bond ***,6：2FTS coordinates with ferric ion to form Fe（III）-6：2FTS complexes,which can undergo ligand-to-metal charge transfer under UV irradiation,causing C-S bond cleavage.

关键词： 6:2 Fluorotelomer sulfonate(6:2FTS) Perfluorooctane sulfonate(PFOS) alternative Ferric ion Photodecomposition

A Characterization of *-Automorphism on B(H)

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Acta Mathematica Sinica,English Series 2010年第2期26卷 287-294页

作者： Run ling AN jin Chuan HOU Department of Applied Mathematics Taiyuan University of Technology Taiyuan 030024 P. R. China

Let H be a Hilbert space and A be a standard ＊-subalgebra of B（H）. We show that a bijective map Ф ： A →A preserves the Lie-skew product AB - BA＊ if and only if there is a unitary or conjugate unitary operator U ∈A（H） such that Ф（A） = UAU＊ for all A ∈ A, that is, Фis a linear ＊ -isomorphism or a conjugate linear ＊-isomorphism.

关键词： *-isomorphism standard operator algebras Lie-skew product

Prediction of Velocity and Deformation Fields During Multipass Plate Hot Rolling by Novel Mixed Analytical-Numerical Method

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Journal of Iron and Steel Research International 2011年第7期18卷 20-27页

作者： ZHANG jin-ling CUI Zhen-shan National Die and Mold CAD Engineering Research Center Shanghai Jiao Tong University Shanghai 200030 China

An integrated mathematical model is proposed to predict the velocity field and strain distribution during multi-pass plate hot rolling. This model is a part of the mixed analytical-numerical method （ANM） aiming at predic- tion of deformation variables, temperature and microstructure evolution for plate hot rolling. First a velocity field with undetermined coefficients is developed according to the principle of volume constancy and characteristics of metal flow during rolling, and then it is solved by minimizing the total energy consumption rate. Meanwhile a thermal model coupling with the plastic deformation is exploited through series function solution to determine temperature distribution and calculate the flow stress. After that, strain rate field is calculated through geometric equations and strain field is derived by means of difference method. This model is employed in simulation of an industrial seven pass plate hot rolling process. The velocity field result and strain field result are in good agreement with that from FEM simulation. Furthermore, the rolling force and temperature agree well with the measured ones. The compari- sons verify the validity of the presented method. The calculation of temperature, strain and strain rate are helpful in predicting microstructure. Above all, the greatest advantage of the presented method is the high efficiency, it only takes 12 s to simulate a seven-pass schedule, so it is more efficient than other numerical methods such as FEM.

关键词： multi-pass plate rolling analytical-numerical method (ANM) velocity field strain field strain rate

The CUSUM statistic of change point under NA sequences

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Applied Mathematics(A Journal of Chinese Universities) 2021年第4期36卷 512-520页

作者： ling jin LI Xiao-qin YANG Wen-zhi JIAO Jian-ling School of Management Hefei University of TechnologyHefei 230009China Center for Applied Mathematics School of Mathematical SciencesAnhui UniversityHefei 230061China

In this paper,we investigate the CUSUM statistic of change point under the neg-atively associated(NA)*** establishing the consistency estimators for mean and covariance functions respectively,the limit distribution of the CUSUM statistic is proved to be a standard Brownian bridge,which extends the results obtained under the case of an indepen-dent normal sample and the moving average ***,the finite sample properties of the CUSUM statistic are given to show the efficiency of the method by simulation studies and an application on a real data analysis.

关键词： CUSUM statistic limit distribution NA sequences Brownian bridge

Synergies between the Belt and Road Initiative and the 2030 SDGs: from the perspective of development

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Economic and Political Studies 2018年第3期6卷 278-292页

作者： ling jin China Institute of International Studies BeijingChina

The Belt and Road Initiative(BRI)has its own development logic,which draws mainly from China’s development and cooperation *** addition to aid,the BRI prioritises ownership,infrastructure connectivity and comprehensive approaches to *** 2030 Sustainable Development Goals(SDGs),drawing many lessons from the implementation of the Millennium Development Goals(MDGs),mark a visible shift from the past donor–recipient relationship to an equal development partnership in the international development *** the two initiatives,this paper identifies synergies between the BRI and the SDGs from the perspective of development and concludes that an emphasis on ownership is the basis for docking the two development *** docking process should begin at the stage of strategic dialogue and policy planning between China and its development partners,and infrastructure connectivity is an area of special importance when seeking synergies and developing differentiated approaches to working in different contexts.

关键词： BRI 2030 SDGs development logic synergies