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A Novel Error Analysis of Spectral Method for the Anomalous Subdiffusion Problems with Multi-term Time-fractional Derivative

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Acta Mathematicae Applicatae Sinica 2023年第4期39卷 943-961页

作者： Bo TANG Yan-ping CHEN Bin XIE xiu-xiu LIN School of Mathematical Sciences South China Normal UniversityGuangzhou520631China

This paper aims to extend a space-time spectral method to address the multi-term time-fractional subdiffusion equations with Caputo derivative. In this method, the Jacobi polynomials are adopted as the basis functions for temporal discretization and the Lagrangian polynomials are used for spatial discretization. An efficient spectral approximation of the weak solution is established. The main work is the demonstration of the well-posedness for the weak problem and the derivation of a posteriori error estimates for the spectral Galerkin approximation. Extensive numerical experiments are presented to perform the validity of a posteriori error estimators, which support our theoretical results.

关键词： space-time spectral methods multi-term time-fractional well-posedness a posteriori error estimates

Focal surface attitude detection for LAMOST

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Research in Astronomy and Astrophysics 2020年第11期20卷 263-272页

作者： Tian-zhu Hu Yong Zhang Xiang-Qun Cui Ye-ping Li xiu-Shan Pan Ying Fu National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of ScienceNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China University of Chinese Academy of Sciences Beijing 100049China

With telescope apertures becoming larger and larger,the deployment of large-field telescopes is becoming increasingly ***,optical path calibration is necessary to ensure the image quality of large-field and large-diameter *** particular,focal plane attitude calibration is an essential optical path calibration technique that has a direct impact on image *** this paper,a focal plane attitude detection method using eight acquisition cameras is proposed based on the calibration requirements of the wide-field telescope,LAMOST(Large Sky Area Multi-Object Fiber Spectroscopic Telescope).Comparison of simulation and experimental results shows that the detection accuracy of the proposed method can reach 30 *** additional testing and verification,this method could be used to facilitate regular focal plane attitude calibration for LAMOST as well as other large-field telescopes.

关键词： methods data analysis techniques high angular resolution techniques image processing

Crystal Structures and DNA Binding Properties of 2-Naphthoxyacetic Acid Cu(Ⅱ) Complexes

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Chinese Journal of Structural Chemistry 2019年第8期38卷 1362-1369页

作者： LIU Yan-zhu GAO Hong-Yan YI xiu-Guang LI Dong-ping LI Yong-xiu School of Science Research Center for Rare Earths&Nano/micro Functional MaterialsNanchang UniversityNanchang 330031China

Two new copper complexes based on 2-naphthoxyacetic acid ligand, namely [Cu(L)2(CH3CN)]2(1) and [Cu(L)(1,10-phen)2](2), where L = 2-naphthoxyacetic acid and 1,10-phen = 1,10-phenanthroline, were obtained by hydrothermal reaction and characterized by single-crystal X-ray diffraction. The binuclear complex 1 and mononuclear complex 2 belong to space group C2/c and P■, respectively. The binding properties of the two compounds with ct-DNA were investigated by UV-Vis and fluorescence spectra. The two compounds could bind with ct-DNA through interactions. Compound 2 displays stronger binding ability in the reaction with ct-DNA.

关键词： 2-naphthoxyacetic acid 1,10-phenanthroline DNA binding spectrum

On growth of meromorphic solutions of some kind of non-homogeneous linear difference equations

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Applied Mathematics(A Journal of Chinese Universities) 2019年第4期34卷 436-445页

作者： ZHENG xiu-Min ZHOU Yan-ping Institute of Mathematics and Information Science Jiangxi Normal University

In this paper,we investigate the growth of meromorphic solutions of some kind of non-homogeneous linear difference equations with special meromorphic *** there are more than one coefficient having the same maximal order and the same maximal type,the estimates on the lower bound of the order of meromorphic solutions of the involved equations are ***,the above estimates are sharpened by combining the relative results of the corresponding homogeneous linear difference equations.

关键词： Complex linear difference equation meromorphic solution order

Kinetics of stripping of gold loaded in DBC organic phase by sodium sulfite

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Rare Metals 2006年第1期25卷 1-6页

作者： zhu ping GU Guobang College of Envirotunent Science and Engineering Shanghai University Shanghai 200072 China Department of Applied Chemistry South China University of Technology Guangzhou 510640 China

The kinetics of stripping of gold loaded in dibutyl carbito （DBC） organic phase by sodittm sulfite was investigated in a Lewis cell. After the stirring speed reached 400 r·min^-1, the reaction of gold stripping conformed with the pseudo-first-order reaction. The stripping rate of gold was in direct proportion to interracial area, concentration of sodittm sulfite and reaction temperature. The experimental results showed that the process of stripping gold was controlled by interfacial chemical reaction, and its activation energy was 36.06 kJ·mol^-1. The kinetics equation was put forward for gold stripping by sodium sulfite.

关键词： kinetics stripping gold Lewis cell

Optimal crater landmark selection based on optical navigation performance factors for planetary landing

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Chinese Journal of Aeronautics 2023年第3期36卷 254-270页

作者： Yi xiu Shengying zhu Rui XU Maodeng LI School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Autonomous Navigation and Control for Deep Space Exploration Ministry of Industry and Information TechnologyBeijing 100081China Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of EducationBeijing 100081China Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control EngineeringBeijing 100091China

Planetary craters are natural navigation landmarks that widely exist and are easily *** navigation based on crater landmarks has become an important autonomous navigation method for planetary *** to the increase in observed crater landmarks and the limitation of onboard computation,the selection of good crater landmarks has gradually become a research hotspot in the field of landmark-based optical *** paper designs a fast crater landmark selection method,which not only considers the configuration observability of crater subsets but also focuses on the influence on navigation performance arising from the measurement uncertainty and the matching confidence of craters,which is different from other landmark selection *** factor of measurement uncertainty,which is anisotropic,correlated and nonidentically distributed,is quantified and integrated into selection based on crater pairing detection and localization error *** addition,the concept of the crater matching confidence factor is introduced,which reflects the possibility of 2D projection measurements corresponding to 3D *** with the configuration observability factor,the crater landmark selection indicator is ***,the effectiveness of the proposed method is verified by Monte Carlo simulations.

关键词： Crater-based optical navigation Crater landmark selection Crater matching Measurement uncertainty Planetary landing

Theoretical Study on the Dark Oxidation Reaction Mechanism of Ethers

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1402-1408页

作者： WANG Gui-xiu zhu Rong-xiu ZHANG Dong-Ju LIU Cheng-Bu School of Chemistry and Chemical Engineering Shandong University Jinan 250100 China

The dark oxidation reactions of ethers including aether, isopropyl ether, phenyl isopropyl ether, and benzyl isopropyl ether have been studied by using density functional theory calculations. The structures of initial Contact charge transfer complexes （CCTCs）, transition states and caged radical intermediates have been located at the B3LYP/6-31G （d） level, The bonding nature of ethers with triplet 02 in CCTCs has been analyzed, and the detailed mechanism of dark oxidation reactions of ether is presented clearly.

关键词： ethers dark oxidation contact charge transfer complex reaction mechanism DFT

No longer ‘blob-ology': Cryo-EM is getting into molecular details

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Science China(Life Sciences) 2015年第11期58卷 1154-1156页

作者： zhu HongTao zhu ping National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences

The structural information of functionally important mac- romolecular assemblies is a key to molecular biology and is of great interest to structural biologists. Cryo-electron mi- croscopy （cryo-EM）, particularly the single particle analysis （SPA）, has been regarded as one of the three primary tech- niques for structure determination, together with X-ray crystallography and nuclear magnetic resonance （NMR）. For single particle cryo-EM, a tiny amount （~3 μL） of puri- fied biological samples at a concentration around 0.1-2 mg mL-1 are placed onto an EM grid, blotted with a filter paper and rapidly frozen into a thin layer of vitreous ice. The EM grid with frozen samples is then transferred to a transmis- sion electron microscope for imaging.

关键词：分子生物学冷冻电镜透射电子显微镜单颗粒分析斑点结构信息 X射线晶体学生物学家

Asymptotic Approximations of Jacobi Functions and Their Zeros with Error Bounds

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Acta Mathematica Sinica,English Series 2006年第3期22卷 729-740页

作者： Xiao Feng zhu xiu Chun LI Department of Basic Science Beijing Institute of Graphic Communication

The study of zeros of orthogonal functions is an important topic. In this paper, by improving the middle variable x（t）, we＇ve got a new form of asymptotic approximation, completed with error bounds, it is constructed for the Jacobi functions φu^（α,β）（t）（α 〉 -1） as μ→∞. Besides, an accurate approximation with error bounds is also constructed correspondingly for the zeros tμ,s of φu^（α,β）（t）（α≥ 0） as μ→∞, uniformly with respect to s = 1, 2,....

关键词： Asymptotic approximation Jacobi function Zero Error bounds