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Journal of Geographical Sciences 2023年第2期33卷 392-412页

作者： WANG Chao WANG xuan WANG Yifan ZHAN Jinyan chu Xi TENG Yanmin LIU Wei WANG Huihui State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Research Center for Eco-environmental Engineering Dongguan University of TechnologySongshan LakeDongguan 523808GuangdongChina College of Geography and Environment Shandong Normal UniversityJinan 250014China

Rapid economic and social change promotes to improve human wellbeing(HW),but poses threats to ecosystems and the *** the coupling relationship between HW and ecosystem services(ES)is crucial for informing high-quality ***,we built a comprehensive index system for HW assessment,and evaluated HW for 17 prefecture-level cities in Shandong province,China,from 2000 to ***,we quantified ES based on land use ***,we assessed the coupling coordination degree and analyzed the relationships between HW and each type of ES *** results were as follows:(1)HW values increased overall in Shandong,with the highest value in Jinan(0.8034)and the lowest value in Heze(0.4965)in 2018.(2)The total ES values for the 17 cities increased *** ranking of 17 cities according to the ES value per unit area was different from the ranking according to the total ES value.(3)All 17 cities in Shandong were in the coordinated development phase after 2015,with increasing coupling coordination *** were clear positive relationships between HW and *** and specific policy recommendations were proposed,providing scientific evidence and a reference for Shandong’s urban management and policy formulation.

关键词： land use coupling human wellbeing ecosystem services Shandong

Modified scaling angular spectrum method for numerical simulation in long-distance propagation

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Chinese Physics B 2021年第3期30卷 266-274页

作者： Xiao-Yi Chen Ya-xuan duan Bin-Bin Xiang Ming Li Zheng-Shang Da The Advanced Optical Instrument Research Department Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

The angular method(AS)cannot be used in long-distance propagation because it produces severe numerical errors due to the sampling problem in the transfer *** ways can solve this problem in AS for long-distance *** is zero-padding to make sure that the calculation window is wide enough,but it leads to a huge calculation *** other is a method called band-limited angular spectrum(BLAS),in which the transfer function is truncated and results in that the calculation accuracy decreases as the propagation distance *** this paper,a new method called modified scaling angular spectrum(MSAS)to solve the problem for long-distance propagation is proposed.A scaling factor is introduced in MSAS so that the sampling interval of the input plane can be adjusted arbitrarily unlike AS whose sampling interval is restricted by the detector’s pixel *** sampling interval of the input plane is larger than the detector’s pixel size so the size of calculation window suitable for long-distance field propagation in the input plane is smaller than the size of the calculation window required by the ***,the method reduces the calculation redundancy and improves the calculation *** results from simulations and experiments show that MSAS has a good signal-to-noise ratio(SNR),and the calculation accuracy of MSAS is better than BLAS.

关键词： angular spectrum diffraction Fourier optics and signal process

Facile Syntheses of 3-Isopentenyl Flavone and 3-Geranyl Flavone

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Chemical Research in Chinese Universities 2012年第6期28卷 994-998页

作者： HUANG chu-sheng SHI Jian-cheng LIU Hong-xing CHEN Qian duan Hong-xia College of Chemistry and Life Sciences Guangxi Teachers Education University Nanning 530001 1~ R. China" Department of Applied Chemistry College of Science China Agricultural University Beijing 100193 P. R. China

Although there was a strong steric effect,isopentenyl and geranyl moieties were successfully introduced into C3 position in flavone skeleton so as to synthesize the 3-isopentenyl flavone and 3-geranyl flavone under two cyclization conditions（AcOH/HCl and concentrated H 2 SO 4 /MeOH） in this *** was found that the optimum cyclization conditions for 3-isopentenyl flavone and 3-geranyl flavone were,respectively,AcOH/HCl and H 2 SO 4 /***,the donating electron ability is in the sequence 3-geranyl flavone3-isopentenyl flavone according to the density functional theory（DFT） calculations,suggesting the longer alkyl chain at 3-position would be more favorable for enhancing the donating electron *** present synthetic routes might reveal potential applicability in our continued studies on the total syntheses of other natural 3-alkyl flavonoids.

关键词： 3-Isopentenyl flavone 3-Geranyl flavone 3-Alkyl flavonoid

In vitro bio-corrosion behaviors of biodegradable AZ31B magnesium alloy under static stresses of different forms and magnitudes

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Journal of Magnesium and Alloys 2023年第3期11卷 1043-1056页

作者： Linyuan Han Zhenwei Zhang Jianwei Dai xuan Li Jing Bai Zhihai Huang Chao Guo Feng Xue Chenglin chu School of Materials Science and Engineering Southeast UniversityNanjing 211189China Jiangsu Key Laboratory for Advanced Metallic Materials Southeast UniversityNanjing 211189China School of Materials Engineering Nanjing Institute of TechnologyNanjing 211189China Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing 211189China

Biomedical degradable materials would be subjected to different degrees and forms of static stress after being implanted in the human *** this work,the biocorrosion behaviors of AZ31B magnesium alloy under different stress forms with different magnitudes(20~150MPa)were *** was found that the corrosion behaviors at stressed conditions were severer than those at unstressed conditions and corrosion rates were obviously *** biocorrosion behaviors are more sensitive to the effects of tensile loads than to compressive loads.A biocorrosion numerical model on the degradation process of Mg alloy under static loads was *** corrosion current density(i_(corr))of Mg alloy and the applied static stress(σ)matches a linear relationship of ln i_(corr)~σwell during the early stage(within 24 hrs)while deviated gradually in the latter period of *** work could provide a guidance and theoretical reference for further researches on the biocorrosion behaviors and practical clinical applications of the biomedical materials subjected to physiological loads.

关键词： Magnesium alloy Biodegradable alloy Biocorrosion behavior Tensile loading Compressive loading

Degradation behaviors of surface modified magnesium alloy wires in different simulated physiological environments

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Frontiers of Materials Science 2014年第3期8卷 281-294页

作者： xuan LI Chao SHI Jing BAI Chao GUO Feng XUE Ping-Hua LIN Cheng-Lin chu School of Materials Science and Engineering and Jiangsu Key Laboratory for Advanced Metallic Materials Southeast University Nanjing 211189 China

The degradation behaviors of the novel high-strength AZ31B magnesium alloy wires after surface modification using micro-arc-oxidization （MAO） and subse- quently sealing with poly-L-lactic acid （PLLA） in different simulated physiological environments were investigated. The results show the surface MAO micropores could be physically sealed by PLLA, thus forming an effective protection to corrosion resistance for the wires. In simulated gastric fluid （SGF） at a low pH value （1.5 or 2.5）, the treated wires have a high degradation rate with a rapid decrease of mass, diameter, mechanical properties and a significant increase of pH value of the immersion fluid. However, surface modification could effectively reduce the degradation rate of the treated wires in SGF with a pH value above 4.0. For the treated wires in simulated intestinal fluid at pH =8.5, their strength retention ability is higher than that in strong acidic SGF. And the loss rate of mass is faster than that of diameter, while the pH value of the immersion fluid decreases. It should be noted that the modified wires in simulated body environment have the best strength retention ability. The wires show the different degradation behaviors indicating their different degradation mechanisms, which are also proposed in this work.

关键词： magnesium alloy wire degradation behavior surface modification simulated physiological environment

Impact behaviors of poly-lactic acid based biocomposite reinforced with unidirectional high-strength magnesium alloy wires

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Progress in Natural Science:Materials International 2014年第5期24卷 472-478页

作者： xuan Li Chao Guo Xiaokai Liu Lei Liu Jing Bai Feng Xue Pinghua Lin Chenglin chu School of Materials Science and Engineering and Jiangsu Key Laboratory for Advanced Metallic Materials Southeast University

A novel poly-lactic acid(PLA) based biocomposite reinforced with unidirectional high-strength magnesium alloy(Mg-alloy) wires for bone fracture fixation was fabricated by hot-compressing process. The macroscopical and microscopical impact behaviors of the biocomposite were investigated using impact experiments and finite element method(FEM), respectively. The results indicated that the biocomposite had favorable impact properties due to the plastic deformation behavior of Mg-alloy wires during impact process. While the content of Mg-alloy wires reached20 vol%, the impact strength of the composite could achieve 93.4 k J/m2, which is approximate 16 times larger than that of pure PLA fabricated by the same process. According to FEM simulation results, the complete destruction life of the composites during impact process increased with increasing volume fraction of Mg-alloy wires, indicating a high impact-bearing ability of the composite for bone fracture ***, the energy absorbed by Mg-alloy wires in the composites had a corresponding increase. In addition, it denoted that the impact properties of the composites are sensitive to the initial properties of the matrix material.

关键词： Impact property Magnesium alloy wire Poly-lactic acid Composite FEM

Ring-Opening Polymerization of Lactide Catalyzed by Bimetallic Salen-Type Titanium Complexes

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Chinese Journal of Chemistry 2017年第5期35卷 640-644页

作者： Ranlong duan Zhi Qu xuan Pang Yu Zhang Zhiqiang Sun Han Zhang Xinchao Bian Xuesi Chen Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130012 China Changchun Institute of Urban Planning & Design Changchun Jilin 130033 China

Three kinds of bimetallic Schiff base titanium complexes with different substituent moieties on organic ligands were ***-opening polymerizations （ROP） of lactides were carried out by using these titanium complexes as *** polymerization data and kinetic studies showed that complex 1a had the highest activity and complex 2a had the lowest activity for ROP of ***,all these three newly synthesized bimetallic titanium complexes showed higher polymerization activity and better molecular weight control than their monometallic counterparts reported in our previous work.

关键词： salen-type titanium complex catalysis ring-opening polymerization

Layered double hydroxide monolayers for controlled loading and targeted delivery of anticancer drugs

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Nano Research 2018年第1期11卷 195-205页

作者： xuan Mei Simin Xu Tongyang Hu Liuqi Peng Rui Gao Ruizheng Liang Min Wei David G. Evans Xue duan State Key Laboratory of Chemical Resource Engineering Beiing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical Technology Beijing 100029 China

Two-dimensional （2D） nanomaterials have gained tremendous attention in the field of biomedicine because of their high specific surface areas and fascinating physicochemical properties. Herein, 2D monolayered double hydroxide （MLDH） nanosheets were employed to localize doxorubicin （DOX）, an anticancer drug, with a loading capacity of as high as 3.6 ***-1 （w/w）. Structural characterizations and theoretical calculations indicate that the DOX molecule is uniformly arranged and oriented at the surface of the MLDHs with a binding energy of 15.90 eV, showing significant electrostatic interaction. With the assistance of the targeting agent folic acid （FA）, DOX-FA/MLDHs demonstrate targeted cellular uptake and superior anticancer behavior based on in vitro tests performed with cancer cells. In addition, this composite material exhibits a selective release toward cancer cells and good biocompatibility with normal cells, which would guarantee its practical applications in cancer therapy.

关键词： two-dimensional nanomaterials monolayer layered double hydroxide(LDH) drug loading controllable release

Broad-band phase retrieval method for transient radial shearing interference using chirp Z transform technique

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Chinese Physics B 2021年第8期30卷 398-406页

作者： Fang Xue Ya-xuan duan Xiao-Yi Chen Ming Li Suo-Chao Yuan Zheng-Shang Da The Advanced Optical Instrument Research Department Xi'an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi'an 710119China University of Chinese Academy of Sciences Beijing 100049China

The transient radial shearing interferometry technique based on fast Fourier transform(FFT)provides a means for the measurement of the wavefront phase of transient light ***,which factors affect the spatial bandwidth of the wavefront phase measurement of this technology and how to achieve high-precision measurement of the broad-band transient wavefront phase are problems that need to be studied *** this end,a theoretical model of phase-retrieved bandwidth of radial shearing interferometry is established in this *** influence of the spatial carrier frequency and the calculation window on phase-retrieved bandwidth is analyzed,and the optimal carrier frequency and calculation window are *** this basis,a broad-band transient radial shearing interference phase-retrieval method based on chirp Z transform(CZT)is proposed,and the corresponding algorithm is *** theoretical simulation,a known phase is used to generate the interferogram and it is retrieved by the traditional method and the proposed method *** residual wavefront RMS of the traditional method is 0.146λ,and it is 0.037λfor the proposed method,which manifests an improvement of accuracy by an order of *** the same time,different levels of signal-to-noise ratios(SNRs)from 50 dB to 10 dB of the interferogram are simulated,and the RMS of the residual wavefront is from 0.040λto 0.066λ.In terms of experiments,an experimental verification device based on a phase-only spatial light modulator is built,and the known phase on the modulator is retrieved from the actual *** RMS of the residual wavefront retrieved through FFT is 0.112λ,and it decreases to 0.035λthrough *** experimental results verify the effectiveness of the method proposed in this ***,the method can be used in other types of spatial carrier frequency interference,such as lateral shearing interference,rotational shearing interference,flipping shearing interference,and

关键词： radial shearing interference chirp Z transform(CZT) phase retrieval

Salen-iron Complexes: Synthesis, Characterization and Their Reactivity with Lactide

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Chinese Journal of Polymer Science 2018年第2期36卷 185-189页

作者： Yuan Liang Ran-Long duan Chen-Yang Hu Li-Li Li xuan Pang Wan-Xi Zhang Xue-Si Chen Department of Materials Science and Engineering Jilin University Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Schiff-base metal complexes as efficient catalysts are widely used in ring-opening polymerization of cycle esters. The salen Fe complexes were formed with their excellent biocompatibility and less toxicity. A series of salen Fe complexes were designed in this work in order to study the activity and control of polymerization of lactide. The salen Fe complexes＇ activities changed with the ligands configuration and substituent groups.

关键词： Salen Fe Ring-opening polymerization Lactide