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Preparation of polymer-supported phosphine from ferrocene for palladium-catalyzed Suzuki-Miyaura cross-coupling reactions

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Chinese Chemical Letters 2007年第1期18卷 37-40页

作者： Hong Wei yu Qing Song Tong Yi Ru peng Li Jia Ji Cheng Shi Zi Lin Jin State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012 China Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China College of Chemistry and Materials Science Fujian Provincial Key Laboratory of Polymer Materials Fujian Normal University Fuzhou 350007 China

Polymer-supported phosphine ligand 3b derived from ferrocene was prepared, and applied in palladium-catalyzed Suzuki- Miyaura reactions. A range of aryl bromides can couple with phenylboronic acid to obtain correspond... 详细信息

关键词： Immobilization Palladium Suzulki-Miyaura reaction Biaryl Catalysis

The Promoting Effect on the Activities ofFe Doped TiO_2 Photocatalysts

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Chemical Research in Chinese Universities 2001年第2期17卷 187-192页

作者： yu Xi-bin, WANG Gui-hua and LI He-xing (Department of Chemistry, Shanghai Normal University, Shanghai 200234, P. R. China) Shanghai Normal Univ Dept Chem Shanghai 200234 Peoples R China

The particles of titanium-iron (Ti/Fe) complex with different Fe contents were prepared by means of the sol-gel method and used as a photocatalyst. The activity of the catalyst was investi- gated as a function of the Fe content during the liquid-phase oxidation of tetracycline, which showed an enhancement at the low Fe content. The XRD, Raman, XPS, and UV-Vis absorp- tion spectra indicated that the crystalline structure of the Ti/Fe complex particles changed from anatase phase to rutile phase when the Fe content increased. The isolated Fe203, Fe304, FeO species were observed and Fe3+ ions were highly dispersed in the TiO2 matrixes, then Ti-O-Fe species were formed. These species increased the surface defects of the Ti/Fe particles. Also, ac- tive hydroxyl radicals could be generated in the catalytic transformation, which led to the higher activity of the catalyst than bare Ti02 for the degradation of tetracycline.

关键词： Titanium Fe doped photocatalyst Photocatalytic activity Tetracycline

NUMERICAL STUDY OF CAVITATION ON THE SURFACE OF THE GUIDE VANE IN THREE GORGES HYDROPOWER UNIT

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Journal of Hydrodynamics 2010年第5期22卷 703-708页

作者： peng yu-cheng CHEN Xi-yang CAO Yan HOU Guo-xiang School of energy and Power Engineering Huazhong University of Science and Technology Wuhan 430074 China College of Electronic Information Engineering Wuhan Polytechnic Wuhan 430074 China School of Traffic Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

Large-area erosions such as rust and obvious cavitation were found on the surface of the guide vane in Three Gorges hydropower units. A numerical explanation of the cavitation is given in this article. At first, based on the characteristic performance curves of the prototype hydro-turbine supplied by ALSTOM together with the actual operating conditions, an operating point is chosen for numerical analysis using the Reynolds-Averaged Navier-Stokes （RANS） equations. The flow passages from the inlet of the spiral case to the outlet of the draft tube are included in the computational domain. The results show that the static pressure on the guide vane surface is much higher than the critical pressure of cavitation. Secondly, a tiny protrusion on the guide vane surface is considered and the problem is simplified to a 2-D problem to study the local detailed flow near the guide vane surface. The protrusion is 0.5 mm in height and is 5.0 mm in width. On the basis of the results of RANS simulations, the 2-D problem is studied using the Large Eddy Simulation （LES）. It is shown that there exists a region in which the static pressure reaches a level below the vapor pressure of the water. Thirdly, a cavitation model is included for the 0.5 mm protrusion case and another tiny pit case, with a tiny pit 0.3 mm in depth and 1.0 mm in width. The results show that vapor bubble exists at the protrusion entrance and the pit exit as the low pressure regions.

关键词： cavitation guide vane numerical analysis

“屈原赋二十五篇”到刘向《楚辞》成书的“聚合之势”考论——兼说今本《楚辞》篇次的来源之二

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三峡大学学报(人文社会科学版) 2025年第1期47卷 18-23+116页

作者：谢天鹏湖南理工学院中国语言文学学院

从屈原《离骚》化用自己《抽思》《涉江》《天问》《远游》《思美人》《惜往日》诸篇，以及宋玉、贾谊、司马迁、东方朔或化用或论及屈作分别达今存七卷中之五卷、六卷、四卷、五卷等情况看，一个共25篇的“屈原集”很可能早已存在，甚... 详细信息

从屈原《离骚》化用自己《抽思》《涉江》《天问》《远游》《思美人》《惜往日》诸篇，以及宋玉、贾谊、司马迁、东方朔或化用或论及屈作分别达今存七卷中之五卷、六卷、四卷、五卷等情况看，一个共25篇的“屈原集”很可能早已存在，甚至就是屈原自己所编。再从司马迁《屈原列传》、东方朔《七谏》看，今存《楚辞》中宋玉等人的拟屈之作也已围绕着屈原及其作品形成了一个“关系网”。因此，刘向编《楚辞》应是基于这样一个“屈原集”加“关系网”,合并、落实、调适而成的。就其“调适”而言，他主要受了司马迁影响，一是依循“时间”标准排列篇次，二是依据“悲其志”主旨进行再选拔；此外，他还引入了“代屈原设言”的写作标准。

关键词：屈原《楚辞》司马迁刘向

Enhanced energy storage properties and good stability of novel(1-x)Na_(0.5)Bi_(0.5)TiO_(3)-xCa(Mg_(1/3)Nb_(2/3))O_(3) relaxor ferroelectric ceramics prepared by chemical modification

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Journal of Materiomics 2024年第4期10卷 770-782页

作者： Ying Zhang Meng-Han Yan Zhi-Fei Zhang Hai-Rui Bai peng Li Wei-Fang Han Ji-Gong Hao Wei Li yu-Chao Li Chun-Ming Wang peng Fu School of Materials Science and Engineering Liaocheng UniversityLiaocheng252059China Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing 300 Changjiang RoadYantai264006China School of Physics Shandong UniversityJinan250100China

The increase in energy consumption and its collateral damage on the environment has encouraged the development of environment-friendly ceramic materials with good energy storage *** this work,(1-x)Na_(0.5)Bi_(0.5)TiO_(3)-xCa(Mg_(1/3)Nb_(2/3))O_(3) ceramics were synthesized by the solid-state reaction *** 0.88Na_(0.5)Bi_(0.5)TiO_(3)-0.12Ca(Mg_(1/3)Nb_(2/3))O_(3) ceramic exhibited a high recoverable energy storage density of 8.1 J/cm3 and energy storage efficiency of 82.4% at 550 kV/*** introduction of Ca(Mg_(1/3)Nb_(2/3))O_(3) reduced the grain size and increased the band gap,thereby enhancing the breakdown field strength of the ceramic *** method also resulted in good temperature stability(20–140℃),frequency stability(1–200 Hz),and fatigue stability over 10^(6) *** addition,an ultrahigh power density of 187 MW/cm^(3) and a fast charge-discharge rate(t_(0.9)=57.2 ns)can be obtained *** element method analysis revealed that the decrease of grain size was beneficial to the increase of breakdown field ***,the 0.88Na_(0.5)Bi_(0.5)TiO_(3)-0.12Ca(Mg_(1/3)Nb_(2/3))O_(3) ceramics resulted in high energy storage properties with good stability and were promising environment-friendly materials for advanced pulsed power systems applications.

关键词： (1-x)Na_(0.5)Bi_(0.5)TiO_(3)-xCa(Mg_(1/3)Nb_(2/3))O_(3)ceramics Relaxor ferroelectrics Breakdown field strength Energy storage properties Stability

FAST:The Five-Hundred-Meter Aperture Spherical Radio Telescope

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Engineering 2023年第9期28卷 21-25页

作者： peng Jiang Hengqian Gan Rui Yao Jinghai Sun Jiguang Lu Dongjun yu Hui Li Jinglong yu Bin Dong Xiaoming Chai Jianing Yin Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550025China FAST Operation and Development Center National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

In the 90 years since its inception,radio astronomy has become the setting of almost all major astronomical discoveries and a hothouse for Nobel Prizes in *** a result,countries all over the world have actively explored new engineering concepts to build large-aperture radio *** by their self-weight and wind load,100 m radio telescopes are regarded as the maximum limit of traditional radio *** perspective allowed the Arecibo 305 m telescope—built by Cornell University in the United States in 1963—to dominate the field for more than half a *** this period,scholars have been exploring how to further expand their horizons in order to make a breakthrough in the problem of the universe.

关键词： breakthrough telescope horizon

PGD: Pineapple Genomics Database

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Horticulture Research 2018年第1期5卷 276-284页

作者： Huimin Xu Qingyi yu Yan Shi Xiuting hua Haibao Tang Long Yang Ray Ming Jisen Zhang Center for Genomics and Biotechnology Haixia Institute of Science and TechnologyFujian Provincial Key Laboratory of Haixia Applied Plant Systems BiologyFujian Agriculture and Forestry University350002FuzhouChina College of Resource and Environment Fujian Agriculture and Forestry University350002FuzhouChina Department of Plant Pathology and Microbiology Texas A&M AgriLife ResearchTexas A&M University SystemDallasTX75252USA Agricultural Big-Data Research Center and College of Plant Protection Shandong Agricultural University271018TaianChina Department of Plant Biology University of Illinois at Urbana-ChampaignUrbanaIL61801USA

Pineapple occupies an important phylogenetic position as its reference genome is a model for studying the evolution the Bromeliaceae family and the crassulacean acid metabolism(CAM)***,we developed a pineapple genomics database(PGD,http://***/pineapple/html/***)as a central online platform for storing and integrating genomic,transcriptomic,function annotation and genetic marker data for pineapple(Ananas comosus(L.)Merr.).The PGD currently hosts significant search tools and available datasets for researchers to study comparative genomics,gene expression,gene co-expression molecular marker,and gene annotation of ***(L).PGD also performed a series of additional pages for a genomic browser that visualizes genomic data interactively,bulk data download,a detailed user manual,and data integration *** was developed with the capacity to integrate future data resources,and will be used as a long-term and open access database to facilitate the study of the biology,distribution,and the evolution of pineapple and the relative plant *** email-based helpdesk is also available to offer support with the website and requests of specific datasets from the research community.

关键词： database browser email

Analysis of the autophagy gene expression profile of pancreatic cancer based on autophagy-related protein microtubule-associated protein 1A/1B-light chain 3

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World Journal of Gastroenterology 2019年第17期25卷 2086-2098页

作者： Yan-Hui Yang yu-Xiang Zhang Yang Gui Jiang-Bo Liu Jun-Jun Sun hua Fan Department of Hepatobiliary Surgery First Affiliated HospitalCollege of Clinical MedicineHenan University of Science and Technology Department of Urology Surgery First Affiliated HospitalCollege of Clinical MedicineHenan University of Science and Technology Department of General Surgery First Affiliated HospitalCollege of Clinical MedicineHenan University of Science and Technology First Affiliated Hospital College of Clinical MedicineHenan University of Science and Technology

BACKGROUND Pancreatic cancer is a highly invasive malignant tumor. Expression levels of the autophagy-related protein microtubule-associated protein 1 A/1 B-light chain 3(LC3) and perineural invasion(PNI) are closely related to its occurrence and development. Our previous results showed that the high expression of LC3 was positively correlated with PNI in the patients with pancreatic cancer. In this study, we further searched for differential genes involved in autophagy of pancreatic cancer by gene expression profiling and analyzed their biological functions in pancreatic cancer, which provides a theoretical basis for elucidating the pathophysiological mechanism of autophagy in pancreatic cancer and *** To identify differentially expressed genes involved in pancreatic cancer autophagy and explore the pathogenesis at the molecular *** Two sets of gene expression profiles of pancreatic cancer/normal tissue(GSE16515 and GSE15471) were collected from the Gene Expression *** analysis of microarrays algorithm was used to screen differentially expressed genes related to pancreatic cancer. Gene Ontology(GO) analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway analysis were used to analyze the functional enrichment of the differentially expressed genes. Protein interaction data containing only differentially expressed genes was downloaded from String database and screened. Module mining was carried out by Cytoscape software and ClusterOne plug-in. The interaction relationship between the modules was analyzed and the pivot nodes between the functional modules were determined according to the information of the functional modules and the data of reliable protein interaction *** Based on the above two data sets of pancreatic tissue total gene expression, 6098 and 12928 differentially expressed genes were obtained by analysis of genes with higher phenotypic correlation. After extracting the intersection of the two differen

关键词： Pancreatic cancer Autophagy-related protein microtubule-associated protein 1A/1B-light chain 3 Perineural invasion Gene Ontology analysis Kyoto Encyclopedia of Genes and Genomes pathway analysis Ubiquitin C

Rational fabrication of ordered porous solid strong bases by utilizing the inherent reducibility of metal-organic frameworks

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Nano Research 2022年第4期15卷 2905-2912页

作者： Song-Song peng Xiang-Bin Shao yu-Xia Li Yao Jiang Chen Gu Manish Kumar Dinker Xiao-Qin Liu(✉) Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech University30 South Puzhu RoadNanjing 211816China

Ordered porous solid strong bases(OPSSBs)have attracted great research interest due to the excellent performance as heterogeneous catalysts in various *** main obstacle for fabricating OPSSBs is the requirement of high temperature to produce strong basicity on ordered porous *** example,the temperatures of 600-650℃ are required for the decomposition of base precursor NaNO_(3)to basic sites on mesoporous silica SBA-15 and zeolite *** high decomposition temperatures are energy-intensive and harmful to the structure of ***,we report the fabrication of OPSSBs by utilizing the redox interaction between base precursor and low-valence metal centers(e.g.,Cr^(3+))in metal-organic frameworks(MOFs).The base precursor NaNO_(3)on MIL-101(Cr)can be converted to basic sites entirely at 300℃,which is quite lower than those of the conventional thermal conversion on SBA-15 and zeolite Y(600-650℃).The exploration on decomposition mechanism reveals that the valence change of Cr^(3+)to Cr^(6+)takes place during the conversion of NaNO_(3)to basic *** this way,MOFs-derived base catalysts have been synthesized successfully by the host-guest redox strategy and exhibit high catalytic activity in typical base-catalyzed reactions.

关键词： metal-organic frameworks ordered porous solid strong bases host–guest redox interaction transesterification reaction Cr centers