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The Electronic and Lattice Structures of the Ground and the Polaron States of Polymer Poly (Phenylene Vinylene) (PPV)

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Communications in Theoretical Physics 2001年第7期36卷 109-114页

作者： YAO Kai-Lun han Si-En duan Yong-Fa Physics Department and National Lab of Laser Technology Huazhong University of Science and Technology Wuhan 430074 China International Center of Material Physics The Chinese Academy of Sciences Shenyang 110015 China Physics Department and National Lab of Laser Technology Huazhong University of Science and Technology Wuhan 430074 China Physics Department and National Lab of Laser Technology Huazhong University of Science and Technology Wuhan 430074 China

The electronic and lattice structures of poly (phenylene vinylene) (PPV) are studied theoretically. Both the electron-electron and electron-phonon interactions are taken into account in the Pariser-Parr-Pople model. The electronic band and the lattice structure of the ground state and the polaronic state are calculated by means of the unrestricted Hartree-Fock method. In the ground state, there exist eight bands in PPV including four valence bands and four conduction bands, and the benzenes can be considered to be rigid. The polaron induces the split of energy bands. There are four localized electronic states within the energy gap. The defect of the polaron appears to extend over about 5 units. The benzenes are strongly affected by the electron-phonon interaction. Our calculation for the energy band structure of the ground and polaron states are consistent with experimental absorption spectra. The results of our calculation show that the electron-phonon and inter-site electron-electron interactions play an important role in determining the electronic and lattice structures.

关键词： electronic structure, polaron state, PPV, benzenes

Controlled Radical Photopolymerization of n-Butyl Methacrylate in Bluk Mediated by HTEMPO

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Chinese Chemical Letters 2006年第8期17卷 1109-1112页

作者： Xiao Xuan LIU Mei han Lun Yong duan Guang Guo WU Department of Chemistry College of Science Shantou University Shantou 515063

Controlled radical photopolymerization of n-butyl methacrylate（n-BMA） mediated by 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxy（HTEMPO） was carried out in bulk at ambient temperature. It was found that obtained n-BMA homopolymers exhibited narrow polydispersities of around 1.4, which was characterized by GPC. Plots of number-average molecular weight vs. conversion and Ln（[Mo]/[M]） vs. time were liner respectively, indicating that was a controlled photopolymerization.

关键词： photopolymerization nitroxide n-butyl methacrylate HTEMPO.

Approximated Vector Potential of Intense Laser Pulses in a Pair Plasma

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Communications in Theoretical Physics 2009年第3期51卷 529-532页

作者： TIAN Duo-Xiang HE Guang-Jun han Jiu-Ning duan Wen-Shan College of Physics and Electronic Engineering Northwest Normal University Lanzhou 730070 China

A （3＋1 ）-dimensional Kadomtse-Petviashvili （KP） equation for nonlinearly interacting intense laser pulses with an electron-positron （e-p） plasma is derived. Taking into account the combined action of the relativistic particle mass increase and the relativistic light ponderomotive force, using the perturbation method, and allowing different types solution, we discuss the analytical solution of （3＋1）-dimensional KP-I equation, and give the approximate solutions of vector potential of the intense laser pulse in e-p plasma. Our results may be significantly useful in understanding the nonlinear wave propagation and interaction of intense laser beams in an e-p plasma.

关键词： electron-positron plasma (3+1)-dimensional KP-I equation lump solution

Preparation and applications of calcium ferrite as a functional material:A review

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 292-310页

作者： Xiuli han Bowen duan Lei Liu Shilong Fang Weiwei Wang College of Mining Engineering North China University of Science and TechnologyTangshan 063210China Collaborative Innovation Center of Green Development and Ecological Restoration of Mineral Resources of Hebei Province Tangshan 063210China Key Laboratory of Mining Development and Security Technology of Hebei Province Tangshan 063210China

Calcium ferrite(CF)is recognized as a potential green and efficient functional material because of its advantages of magnetism,electrochemistry,catalysis,and biocompatibility in the fields of materials chemistry,environmental engineering,and ***-fore,the obtained research results need to be systematically summarized,and new perspectives on CF and its composite materials need to be *** on the presented studies of CF and its composite materials,the types and structures of the crystal are *** addition,the current application technologies and theoretical mechanisms with various properties in different fields are ***,the various preparation methods of CF and its composite materials are elaborated in *** importantly,the advantages and disadvantages of the synthesis methods of CF and its composite materials are discussed,and the existing problems and emerging challenges in practical production are ***,the key future research directions of CF and its composite materials have been prospected from the potential application technologies to provide references for its synthesis and efficient utilization.

关键词： calcium ferrite mineral functional materials preparation application perspectives

Efficient One-pot Synthesis of 12-Aryl-8, 9, 10, 12- tetrahydrobenzo [a]anthen-11-ones Under Solvent-free Conditions

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Chemical Research in Chinese Universities 2013年第1期29卷 82-86页

作者： JIA Xu-dong han Song-yang duan Hai-feng LIN Ying-jie CAO Jun-gang LIANG Da-peng WUMao-cheng Department of Organic Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

Multi-component condensation of 2-naphthol, aromatic aldehydes, and cyclic 1,3-dicarbonyl compounds catalyzed by ionic liquid [NSPTEA][HSO4] was accomplished for the synthesis of a series of 12-aryl-8,9,10,12- tetrahydrobenzo[a]xanthen-11-ones under solvent-free conditions. High yields, ease recovery, short reaction time and reusability of catalyst are significant advantages. ZrOC12＂8H20 was also found to act as an effective catalyst towards this transformation.

关键词： Aldehyde Ionic liquid ZrOCI28HzO Multi-component reaction Solvent-free condition

Optimization of Blade Motion of Vertical Axis Turbine

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China Ocean Engineering 2016年第2期30卷 297-308页

作者：马勇张亮张之阳韩端锋 College of Shipbuilding Engineering Harbin Engineering University

In this paper,a method is proposed to improve the energy efficiency of the vertical axis *** of all,a single disk multiple stream-tube model is used to calculate individual *** algorithm is adopted to optimize blade pitch motion of vertical axis turbine with the maximum energy efficiency being selected as the optimization ***,a particular data processing method is proposed,fitting the result data into a cosine-like *** that,a general formula calculating the blade motion is ***,CFD simulation is used to validate the blade pitch motion *** results show that the turbine＇s energy efficiency becomes higher after the optimization of blade pitch motion;compared with the fixed pitch turbine,the efficiency of variable-pitch turbine is significantly improved by the active blade pitch control;the energy efficiency declines gradually with the growth of speed ratio;besides,compactness has lager effect on the blade motion while the number of blades has little effect on it.

关键词： tidal current energy vertical axis turbine optimization of blade motion single disk multiple stream-tube model CFD

Skmer approach improves species discrimination in taxonomically problematic genus Schima(Theaceae)

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Plant Diversity 2024年第6期46卷 713-722页

作者： han-Ning duan Yin-Zi Jiang Jun-Bo Yang Jie Cai Jian-Li Zhao Lu Li Xiang-Qin Yu CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanPR China College of Forestry Southwest Forestry UniversityKunming 650224YunnanPR China Genomics and Genetic Engineering Laboratory of Ornamental Plants College of Agriculture and BiotechnologyZhejiang UniversityHangzhouZhejiangPR China Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanPR China Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology Laboratory of Ecology and Evolutionary BiologySchool of Ecology and Environmental SciencesYunnan UniversityKunming 650500YunnanPR China

Genome skimming has dramatically extended DNA barcoding from short DNA fragments to next generation barcodes in ***,conserved DNA barcoding markers,including complete plastid genome and nuclear ribosomal DNA(nrDNA)sequences,are inadequate for accurate species ***,a recently proposed approach that estimates genetic distances among species based on unassembled genome skims,has been proposed to effectively improve species discrimination *** this study,we used Skmer to identify species based on genomic skims of 47 individuals representing 10 out of 13 species of Schima(Theaceae)from *** unassembled reads identified six species,with a species identification rate of 60%,twice as high as previous efforts that used plastid genomes(27.27%).In addition,Skmer was able to identify Schima species with only 0.5sequencing depth,as six species were well-supported with unassembled data sizes as small as 0.5 *** findings demonstrate the potential for Skmer approach in species identification,where nuclear genomic data plays a crucial *** taxonomically difficult taxa such as Schima,which have diverged recently and have low levels of genetic variation,Skmer is a promising alternative to next generation barcodes.

关键词： Schima Genome skimming Species discrimination Skmer

The effect of estrogen-mediated ubiquitin on cardiovascular diseases:a bioinformatics analysis

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Precision Medicine Research 2023年第1期5卷 3-8页

作者： Nan Li Yu-han duan Kun Zhang Department of Research Center The Second Hospital of Jilin UniversityChangchun 130000China

Objective:Using data mining tools,study the potential pathways of estrogen’s cardiovascular ***:The GeneExpression Omnibus database was used to download the relevant high-throughput microarray dataset GSE72180,which was then analyzed for differential genes using the GEO2R online analysis tool,gene function and pathway enrichment analysis using DAVID 6.8,protein interaction network analysis using the STRING database,and core network extraction using the MCODE ***:A total of 131 differential genes were identified and enriched for gene function and signaling pathway analysis,which indicated that these genes were related with focal adhesion and the HIF-1 signaling *** algorithm analysis extracted 1 core sub-network of these genes to be related to ubiquitin protein transferase activity,protein polyubiquitination,protein ubiquitination involved in ubiquitin-dependent proteolytic metabolic processes,ligase activity,and clustering on ubiquitin-mediated protein hydrolysis signaling ***:By using data mining tools,it is possible to identify how estrogen may influence the cardiovascular system by controlling the ubiquitination *** information may be used as a reference for etiology and preventive studies of cardiovascular illnesses.

关键词： estrogen data mining cardiovascular ubiquitination modification

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锰对高铬铸铁凝固过程和组织的影响

热加工工艺 2001年第3期30卷 23-25页

作者：段汉桥华中科技大学材料学院湖北武汉430074

研究了锰对高铬铸铁凝固过程和组织的影响。结果表明 :锰降低液相线温度和共晶温度 ,缩小凝固温度范围 ;锰降低奥氏体向珠光体转变温度 ,增加碳和铬等元素在奥氏体中的饱和溶解度 ,从而大大增加奥氏体的稳定性 ;随锰量的增加 ,高铬铸铁... 详细信息

研究了锰对高铬铸铁凝固过程和组织的影响。结果表明 :锰降低液相线温度和共晶温度 ,缩小凝固温度范围 ;锰降低奥氏体向珠光体转变温度 ,增加碳和铬等元素在奥氏体中的饱和溶解度 ,从而大大增加奥氏体的稳定性 ;随锰量的增加 ,高铬铸铁铸态组织中残余奥氏体量增加 ,铸态硬度相应下降 ;

关键词：高铬铸铁凝固锰组织性能