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Taxayuntin I from Thous Yunnanensis

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Chinese Chemical Letters 1999年第1期10卷 43-44页

作者： Jin Yun ZHOU Pei Ling ZHANG wei ming chen and qi cheng fang(Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking UnionMedical College, Beijing 100050)

Taxayuntin I, a new 11I (15→1)abeotaxane. was isolated from the leaves and stems ofTaxes yunnanensis. Its structure was elucidated on the basis of spectroscopic data.

关键词： TaxusyUnnanensis taxoids abeotaxane taxayuntin I

Selective hydrogenation of 4-nitrostyrene to 4-nitroethylbenzene catalyzed by Pd@Ru core–shell nanocubes

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Rare Metals 2022年第4期41卷 1189-1194页

作者： Jing-Jing fang qi-ming Liu Xiong-Wu Kang Shao-wei chen New Energy Technology Institute School of Environment and EnergySouth China University of TechnologyGuangzhou 510006China Department of Chemistry and Biochemistry University of CaliforniaCA 95064USA

It is a challenge to selectively hydrogenate 4-nitrostyrene to 4-nitroethylbenzene,due to the similar energy barrier of hydrogenation of the nitro and vinyl ***,we demonstrate that such selective hydrogenation can be achieved by Pd@Ru core–shell nanocubes that are pre-pared by epitaxial growth of a face-centered cubic Ru shell on Pd *** core–shell structure of Pd@Ru nanocubes is conflrmed by transmission electron microscopy,X-ray diffraction spectroscopy,and elemental mapping *** is found that the electronic structure and hence the catalytic activity of the Pd@Ru nanocubes can be readily modulated by the Ru shell *** is manifested in electrochemical CO stripping measurements where a decrease of CO adsorption energy is observed on Pd@Ru nanocubes with the increase of the Ru shell *** from this study suggest that deliberate structural engineering can be exploited to prepare bimetallic core–shell nanostructures for highly active and selective hydrogenation of organic molecules with multi-functional moieties.

关键词： hydrogenation styrene benzene

Stress release in high-capacity flexible lithium-ion batteries through nested wrinkle texturing of graphene

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Journal of Energy Chemistry 2021年第10期30卷 243-249,I0008页

作者： Jing chen Lei Wen Ruopian fang Da-wei Wang Hui-ming cheng Feng Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026.AnhuiChina School of Chemical Engineering The University of New South WalesSydney 2052Australia Tsinghua-Berkeley Shenzhen Institute Tsinghua UniversityShenzhen 518055GuangdongChina

Flexible lithium-ion batteries(LIBs)are critical for the development of next-generation smart *** reaction-based electrodes have been considered promising to construct high energy-density flexible LIBs,which satisfy the ever-increasing demand for practical ***,these electrodes suffer from inferior lithium-storage performance and structural instability during deformation and long-term lithiation/*** are caused by the sluggish reaction kinetics of active-materials and the superposition of responsive strains originating from the large lithiation-induced stress and applied ***,we propose a stress-release strategy through elastic responses of nested wrinkle texturing of graphene,to achieve high deformability while maintaining structural integrity upon prolonged cycles within high-capacity *** wrinkles endow the electrode with a robust and flexible network for effective stress *** resulting electrode shows large reversible stretchability,along with excellent electrochemical performance including high specific capacity,high-rate capability and long-term cycling *** strategy offers a new way to obtain high-performance flexible electrodes and can be extended to other energy-storage devices.

关键词： Wrinkling graphene Structural design Stress release High-capacity active material Flexible electrodes

Explosion temperature mapping of emulsion explosives containing TiH_(2)powders with the two-color pyrometer technique

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Defence Technology（防务技术） 2022年第10期18卷 1834-1841页

作者： Yu-Le Yao Yang-Fan cheng qi-wei Zhang Yu Xia fang-fang Hu Quan Wang Yuan chen State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan232001PR China School of Chemical Engineering Anhui University of Science and TechnologyHuainan232001PR China Anhui Engineering Laboratory of Explosive Materials and Technology Anhui University of Science and TechnologyHuainan232001PR China Quality Department The 38th Research Institute of China Electronics Technology Group CorporationHefei230088PR China

In the study,the two-color pyrometer technique was used to measure the transient temperature field of emulsion explosives with different contents of TiH_(2)*** experimental results showed that the introduction of TiH_(2)powders could significantly increase the explosion temperature and fireball duration of emulsion *** emulsion explosives were ignited,the average explosion temperature of pure emulsion explosive continuously decreased while emulsion explosives added with TiH_(2)powders increased at first and then *** the content of TiH_(2)powders was 6 mass%,the explosion average temperature reached its maximum value of 3095 K,increasing by 43.7%as compared with that of pure emulsion *** addition,the results of air blast experiment and explosion heat test showed that the variation trends of shock wave parameters,explosion heat and theoretical explosion temperature of emulsion explosives with different contents of TiH_(2)powders were basically consistent with that of explosion temperature measured by the two-color pyrometer *** conclusion,the two-color pyrometer technique would be conducive to the formula design of emulsion explosive by understanding the explosion temperature characteristics.

关键词： Two-color pyrometer Emulsion explosive Explosion temperature field Explosion heat

Mitochondrial phylogenomics provides insights into the phylogeny and evolution of spiders(Arthropoda:Araneae)

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Zoological Research 2022年第4期43卷 566-584页

作者： Min Li Wen-Ting chen qi-Lin Zhang Min Liu cheng-wei Xing Ya Cao fang-Zhen Luo ming-Long Yuan State Key Laboratory of Grassland Agro-Ecosystems Lanzhou UniversityLanzhouGansu 730020China College of Pastoral Agriculture Science and Technology Lanzhou UniversityLanzhouGansu 730020China National Demonstration Center for Experimental Grassland Science Education Lanzhou UniversityLanzhouGansu 730020China Faculty of Life Science and Technology Kunming University of Science and TechnologyKunmingYunnan 650500China Lanzhou University Second Hospital Lanzhou UniversityLanzhouGansu 730030China

Spiders are among the most varied terrestrial predators,with highly diverse morphology,ecology,and *** and molecular data have greatly contributed to advances in the phylogeny and evolutionary dynamics of ***,we performed comprehensive mitochondrial phylogenomics analysis on 78 mitochondrial genomes(mitogenomes)representing 29 families;of these,23 species from eight families were newly *** retained the same gene arrangement as the arthropod ancestor(Limulus polyphemus),while Opisthothelae showed extensive rearrangement,with 12 rearrangement types in transfer RNAs(tRNAs)and control *** spider tRNAs were extremely truncated and lacked typical dihydrouridine or TΨC arms,showing high tRNA structural diversity;in particular,trnS1 exhibited anticodon diversity across the *** evolutionary rates of mitochondrial genes were potentially associated with gene rearrangement or truncated *** mitogenomic sequences and rearrangements possessed phylogenetic characteristics,providing a robust backbone for spider phylogeny,as previously *** monophyly of suborder,infraorder,retrolateral tibial apophysis clade,and families(except for Pisauridae)was separately supported,and high-level relationships were resolved as(Mesothelae,(Mygalomorphae,(Entelegynae,(Synspermiata,Hypochilidae)))).The phylogenetic positions of several families were also resolved(e.g.,Eresidae,Oecobiidae and Titanoecidae).Two reconstructions of ancestral web type obtained almost identical results,indicating that the common ancestor of spiders likely foraged using a silk-lined *** study,the largest mitochondrial phylogenomics analysis of spiders to date,highlights the usefulness of mitogenomic data not only for providing efficient phylogenetic signals for spider phylogeny,but also for characterizing trait diversification in spider evolution.

关键词： Spiders Mitochondrial genome Gene rearrangement Truncated tRNAs Trait evolution Phylogenomics

Synthesis of Poly(styrene-b-isoprene-b-styrene)viaNitroxide-mediated Radical Polymerization by a Novel Alkoxyamine

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Chemical Research in Chinese Universities 2005年第5期21卷 615-618页

作者： GAO Long-cheng PAN qi-wei FAN Xing-he chen Xiao-fang WAN Xin-hua ZHOU qi-feng College of Chemistry and Molecular Engineering Peking University Beijing 100871 P. R. China Key Laboratory of Polymer Chemistry and Physics of Ministry of Education Bering 100871 P. R. China

Bifunctional alkoxyamine bis-TIPNO derived from 2,2,5-trimethyl-4-phenyl-3-azahexane-3-oxyl （TIPNO） and α, ω-alkyl bromide by atom transfer radical addition（ATRA） was employed as “biradical initiator” for nitroxide-mediated radical polymerization（NMRP） of isoprene and styrene. The kinetics study for the polymerization of styrene at different time showed living features. The poly（styrene-b-isoprene-b-styrene）（SIS） copolymers have two glass transition temperatures, indicating the immiscibility of the corresponding blocks.

关键词： Radical polymerization Block copolymer Nitroxide Isoprene

Host-Guest Chemistry and Nonlinear Optical Behaviors of Aluminum Molecular Rings

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Chinese Journal of Chemistry 2024年第21期42卷 2581-2588页

作者： Yi-Bo chen cheng-Yang Zhang Dan Luo Ran-qi chen Jian Zhang Shu-Mei chen wei-Hui fang College of Chemistry Fuzhou UniversityFuzhouFujian350108 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian350002 China Fujian College University of Chinese Academy of SciencesNo.155 Yangqiao West RoadFuzhouFujian350002 China

Macrocyclic compounds are of great interest for their ability to capture guest molecules into their *** particular,host-guest interaction plays a crucial role in the formation of supramolecular ***,two host-guest supramolecular compounds,[Al_(8)(OH)_(8)(L)_(16)]·2HL(HL@AlOC-166,HL=4-Iodobenzoic acid)and[Al_(8)(OH)_(8)(L)_(8)(L1)_(8)]·2DMF(DMF@AlOC-166,HL1=isoamyl alcohol),are acquired by introducing different types of guest components based on the internal pore cavities of the aluminum molecular ring[Al_(8)(OH)_(8)(L)_(16)](AlOC-166).The inclusion of these guests is attributed to the presence of abundant hydrophilic OH serving as the hydrogen bond donors inward the ring ***-guest compounds usually exhibit superior nonlinear optical(NLO)response due to the existence of guest molecules that could change symmetry,dipole moments,charge distributions,***,the AlOC-166 achieved the best NLO results,although it had no guest molecules inside its molecular ring,which breaks the traditional *** reason for this trend can be explained by the difference in intermolecular force rather than intramolecular interaction,mainly related to the amount and strength ofπ···πand C—I···πinteractions in different *** work investigates the effect of host-guest interaction on NLO,representing a new perspective for designing optical limiting materials.

关键词： Host-guest chemistry Noncovalent interaction Nonlinear optical Aluminum molecular ring

Facile Synthesis of High Molecular weight Polypeptides via Fast and Moisture Insensitive Polymerization of a-Amino Acid N-Carboxyanhydrides

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Chinese Journal of Polymer Science 2020年第10期38卷 1131-1140,I0007页

作者： Yue ming Wu wei-wei Zhang Rui-Yi Zhou qi chen chen-Yu Xie Heng-Xue Xiang Bin Sun Mei-fang Zhu Run-Hui Liu State KeyLaboratory of Bioreactor Enginering East China Uniersity of Science and TechnologyShanghai 200237China State Key Laboratory for Modification of Chemical Fibers and Polymer Materals College of Materias Science and EngineringDonghua UniversityShanghai 201620China Key Laboratory of Specally Functional Polymeric Materials and Related Technology(ECUST)Ministry of Education Key Laboratory for Ultrafine Materials of Ministry of EducationResearch Center for Biomedical Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

Polypeptides have been widely utilized in the fields of biomaterials and *** since N-carboxyanhydride(NCA)was reported by Hermann Leuchs in 1906,ring-opening polymerization of NCAS has been extensively used to prepare *** continuous innovations,it is still challenging to synthesize polypeptides in high molecular weight *** address this challenge,we developed KHMDS/NaHMDS initiated fast NCA polymerization that is also moisture tolerant,open-flask amenable and terminal *** NCA polymerization was able to proceed in most common solvents and meet the solubility requirement of variable NCA monomers and corresponding *** can initiate r benzy-L glutamate-N carboxyanhydride(BLG NCA)polymerization in a reaction rate 92 times faster than does hexylamine and 80 times faster than does *** NCA polymerization also demonstrated easy and fast synthesis of gram-scale long chain polypeptides in an open flask.

关键词： NCA polymerization Polypeptide Open vessel Fast polymerization High Mw

Antimicrobial Properties and Application of Polysaccharides and Their Derivatives

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Chinese Journal of Polymer Science 2021年第2期39卷 133-146,I0004页

作者： Gui-Xue Xia Yue-ming Wu Yu-fang Bi Kang chen wei-wei Zhang Shi-qi Liu Wen-Jing Zhang Run-Hui Liu State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai 200237China Frontiers Science Center for Materiobiology and Dynamic Chemistry Key Laboratory of Specially Functional Polymeric Materials and Related Technology(ECUST)Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

With the quick emergence of antibiotic resistance and multi-drug resistant microbes,more and more attention has been paid to the development of new antimicrobial agents that have potential to take the ***,as one of the major classes of biopolymers,were explored for their antimicrobial properties and applications,owing to their easy accessibility,biocompatibility and easy *** and their derivatives have variable demonstrations and applications as antimicrobial agents and antimicrobial biomaterials.A variety of polysaccharides,such as chitosan,dextran,hyaluronic acid,cellulose,other plant/animal-derived polysaccharides and their derivatives have been explored for antimicrobial *** expect that this review can summarize the important progress of this field and inspire new concepts,which will contribute to the development of novel antimicrobial agents in combating antibiotic resistance and drug-resistant antimicrobial infections.

关键词： Antimicrobial Drug resistance Polysaccharides Polysaccharide derivatives Chitosan