检索结果-南通市图书馆

Iron-catalyzed benzylation of 1,3-dicarbonyl compounds by simple toluene derivatives

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2012年第19期57卷 2382-2386页

作者： PAN ShiGuang liU JinHua li yuanming li ZhiPing Department of Chemistry Renmin University of ChinaBeijing 100872China

An iron-catalyzed oxidative C-C bond formation by the reactions of simple toluene derivatives with 1,3-dicarbonyl compounds is developed.A benzylic radical addition to a benzoylmethanato iron species is proposed for t... 详细信息

关键词：二羰基化合物苯衍生物催化氧化苄基铁自由基

Photoactive donor-acceptor conjugated macrocycles:New opportunities for supramolecular chemistry

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2023年第8期34卷 28-48页

作者： Shanyuan Zhong lingyun Zhu Shuai Wu yuanming li Meijin lin Key Laboratory of Molecule Synthesis and Function Discovery and Fujian Provincial Key Laboratory of Electrochemical Energy Storage MaterialsCollege of ChemistryFuzhou UniversityFuzhou 350116China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350116China

The design and synthesis of photoactive macrocyclic molecules continue to attract attention because such species play important roles in supramolecular chemistry as well as photoelectronic ***(D-A)conjugated macrocycles are an emerging class of photoactive molecules due to their D-A conjugated structural characteristics and tunable optical *** addition,the well-defined cavities in such D-A macrocycles endow them with versatile host-guest *** this review,we provide a comprehensive summary of D-A conjugated macrocycle chemistry,detailing recent progress in the area of synthetic methods,optical properties,host-guest chemistry and applications of the underlying chemistry to chemical sensors,bioimaging and photoelectronic *** objective is to provide not only a review of the fundamental findings,but also to outline future research directions where D-A conjugated macrocycles and their constructs may have a role to play.

关键词： Conjugated macrocycles Donor-acceptor Photoactive Supramolecular chemistry Photoelectronic materials

In-situ TEM study of the effect of hydrogen-helium ratio on defect characteristics in Fe9Cr1.5W0.4Si F/M steel during H_(2)^(+)&He^(+)simultaneous irradiation

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第6期173卷 192-201页

作者： Dewang Cui Ziqi Cao Kun He yuanming li Xi Qiu Guang Ran College of Energy Xiamen UniversityXiamen 361102China Fujian Provincial Nuclear Energy Engineering Technology Research Center Xiamen 361102China Science and Technology on Reactor Fuel and Materials Laboratory Chengdu 610041China Nuclear Power Institute of China Chengdu 610041China Science and Technology on Reactor System Design Technology Laboratory Chengdu 610041China

The effect of hydrogen and helium interaction,especially H-He ratio,on the irradiation behavior of nuclear materials has not yet been ***,this is an important basis for evaluating the irradiation properties of nuclear materials and developing high irradiation resistant ***,30 keV H_(2)^(+)and He^(+)dual beams with four H-He ratios of 0:10,3:10,15:10,and 30:10 were used to irradiate the newly developed Fe9Cr1.5W0.4Si F/M steel in TEM to in-situ study the interaction and ratio effect of hydrogen and *** addition of H atoms significantly promoted the nucleation of dislocation loops and *** the early stage of irradiation,the average size and density of dislocation loops increased with the increase of H-He ***,the larger the H-He ratio,the easier it was to form a complex dislocation ***,the final saturation size of bubbles increased with the increase of H-He *** was first found that the swelling was affected by H concentrations,with high H concentrations slowing down the increase in *** a certain irradiation dose,a specific H-He ratio would lead to a swelling peak of Fe9Cr1.5W0.4Si F/M *** super-sized bubbles at grain boundaries(GBs)were found after H addition,resulting in a bigger swelling of GBs than the *** the swelling of the GBs and the matrix show a dependence on the H-He *** current work is of great significance for understanding the interaction between hydrogen and helium in nuclear materials.

关键词： Dose ratio effect Ferritic-martensitic steel Hydrogen&helium synergetic irradiation In-situ TEM

When nanocarbon science meets with molecular machine:A new type of mechanically interlocked molecules(MIMs)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2023年第4期42卷 4-6页

作者： Bin Lan Ruiying Zhang Jianfeng Yan Yaofeng Yuan yuanming li Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou350108China

The discovery of new carbon nanomaterials such as fullerenes,carbon nanotubes,graphene,and graphyne has always driven the development of various fields of science[1].The arrangement of carbon atoms largely influences their *** the past decade,the atomic-precision synthesis and study of molecular nanocarbons,which is the sub-structures of larger carbon nanostructures,have attracted huge attention[2].Among them,the synthesis of cycloparaphenylene(CPP)(the substructure of carbon nanotubes)has been developed considerably since 2008[3].Recently,topologically complex nanocarbon[4]starting from CPP or oligoparaphenylene-derived carbon nanohoop has been explored as a new type of MIM,which undoubtedly revolutionizes a wide range of sciences,especially in the field of molecular machine(Fig.1)[5].

关键词： properties. carbon synthesis

Modeling of Mesoscale Creep Behaviors and Macroscale Creep Responses of Composite Fuels Under Irradiation Conditions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2022年第6期35卷 1040-1054页

作者： Jing Zhang Jingyu Zhang Haoyu Wang Changbing Tang Pan Yuan Chunyu Yin Shurong Ding yuanming li Institute of Mechanics and Computational Engineering Department of Aeronautics and AstronauticsFudan UniversityShanghai200433China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu610213China

A finite-strain homogenization creep model for composite fuels under irradiation conditions is developed and verified,with the irradiation creep strains of the fuel particles and matrix correlated to the macroscale creep responses,excluding the contributions of volumetric strain induced by the irradiation swelling deformations of fuel particles.A finite element(FE)modeling method for uniaxial tensile creep tests is established with the irradiation effects of nuclear materials taken into *** proposed models and simulation strategy are numerically implemented to a kind of composite nuclear fuel,and the predicted mesoscale creep behaviors and the macroscale creep responses are *** research results indicate that:(1)the macroscale creep responses and the mesoscale stress and strain fields are all greatly affected by the irradiation swelling of fuel particles,owing to the strengthened mechanical interactions between the fuel particles and the matrix.(2)The effective creep rates for a certain case are approximately two constants before and after the critical fission density,which results from the accelerated fission gas swelling after fuel grain recrystallization,and the effects of macroscale tensile stress will be more enhanced at higher temperatures.(3)The macroscale creep contributions from the fuel particles and matrix depend mainly on the current volume fractions varying with fission density.(4)As a function of the macroscale stress,temperature,initial particle volume fraction and particle fission rate,a multi-variable mathematical model for effective creep rates is fitted out for the considered composite fuels,which matches well with the FE *** study supplies important theoretical models and research methods for the multi-scale creep behaviors of various composite fuels and provides a basis for simulation of the thermal–mechanical behavior in related composite fuel elements and assemblies.

关键词： Composite fuels Effective irradiation creep rate model Homogenization creep theory Irradiation swelling Large deformation

Synthesis and Properties of Ferrocene Conjugated Macrocycles with Illusory Topology of the Penrose Stairs

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2024年第5期40卷 881-886页

作者： XU Jindong LAN Bin ZHU lingyun XU Hui CHEN Xinyu li Wenjuan YUAN Yaofeng YAN Jianfeng li yuanming Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou350108P.R.China Henan Key Laboratory of Biomolecular Recognition and Sensing College of Chemistry and Chemical EngineeringShangqiu Normal UniversityShangqiu476000P.R.China

Polyferrocene macrocycles hold immense potential in the fields of molecular electronics and electrochemistry,primarily due to their multiple metal ***,developing highly efficient synthetic strategies for constructing these rings remains a significant *** this study,we successfully synthesized triferrocenyl macrocycles using Pt-mediated coupling strategy and determined their configuration using single-crystal X-ray diffraction analysis,revealing a structure reminiscent of the Penrose *** comprehensively investigated the macrocycle’s structure,photophysical properties,and employed density functional theory(DFT)calculations to gain further ***,this macrocycle exhibits several advantageous features,including a flexible structure,good solubility,and a highly efficient synthetic pathway.

关键词： Conjugated macrocycle Organometallic macrocycle Pt-template method

Magnetism in Mn and Co doped ZnO bulk samples

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2007年第8期52卷 1019-1023页

作者： WANG YongQiang YUAN Songliu SONG YunXing liU li TIAN ZhaoMing li Pai ZHOU yuanming li YunLong YIN ShiYan Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

Bulk samples with nominal composition Zn0.95Co0.05O and Zn0.92Co0.05Mn0.03O were fabricated by a solid-state reaction method at 600℃.X-ray diffraction experiment showed that the peaks of secondary phase Co3O4 with a cubic structure were visible in both samples,besides the main peaks of wurtzite structure as *** measurement indicated that doping Co alone can induce ferromag- netism in ZnO itself,while the introduction of Mn significantly enhances ***, both samples showed different magnetic behavior at temperatures below 50 *** was also noted that ferromagnetic coupling interaction was weakened due to the presence of antiferromagnetic Co3O4.

关键词：锰钴掺杂氧化锌块磁性铁磁现象

Multiple Resonance Thermally Activated Delayed Fluorescence Sensitizers Enable Green-toUltraviolet Photon Upconversion:Application in Photochemical Transformations

在线全文

学校读者我要写书评

暂无评论

CCS Chemistry 2022年第12期4卷 3852-3863页

作者： Yaxiong Wei Ke Pan Xiaosong Cao yuanming li Xiaoguo Zhou Chuluo Yang Shenzhen Key Laboratory of Polymer Science and Technology College of Materials Science and EngineeringShenzhen UniversityShenzhen 518060 School of Physics and Electronic Information Anhui Normal UniversityWuhuAnhui 241000 Department of Chemical Physics University of Science and Technology of ChinaHefeiAnhui 230026

Efficient visible-to-ultraviolet(UV)triplet-triplet annihilation upconversion(TTA-UC)with large anti-Stokes shift is highly promising for solar-powered and indoor ***,the excitationwavelengthis confined to the blue region(lization efficiency in practical ***,a series of multiple resonance thermally activated delayed fluorescence(MR-TADF)compounds are developed as purely organic sensitizers for the purpose of energy-loss reduction,which also feature intense absorbance in the visible region,high intersystem crossing efficiencies,and long triplet *** pairing the MR-TADF sensitizers with appropriate acceptors,green-to-UV TTA-UC systems were realized with an anti-Stokes shift up to 1.05 eV,upconversion quantum yield up to 8.6%,and threshold excitation intensity as low as 9.2 mW cm^(−2) in *** TTA-UC pairs were applied as internal or external sources of UV photons to trigger energy-demanding photopolymerization and photoligation reactions even under excitation of low-power-density green light-emitting diode light,revealing the broad utility of thesemolecular *** work unlocks the huge potential of MR-TADF-type sensitizers in upconversion applications.

关键词： triplet-triplet annihilation upconversion visible-to-ultraviolet upconversion multiple resonance photochemical reactions

Chemical Synthesis of Carbon Nanorings and Nanobelts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Accounts of Materials Research 2021年第8期2卷 681-691页

作者： yuanming li Hideya Kono Takehisa Maekawa Yasutomo Segawa Akiko Yagi Kenichiro Itami Institute of Transformative Bio-Molecules(WPI-ITbM)and Department of Chemistry Graduate School of ScienceNagoya UniversityNagoya 464-8602Japan Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou 350108 FujianChina Department of Chemistry Graduate School of ScienceNagoya UniversityNagoya 464-8602Japan Institute of Chemistry Academia SinicaTaipei 115 TaiwanR.O.C Institute for Molecular Science MyodaijiOkazaki 444-8787Japan Department of Structural Molecular Science SOKENDAI(The Graduate University for Advanced Studies)MyodaijiOkazaki 444-8787Japan Institute of Chemistry Academia SinicaTaipei 115 TaiwanR.O.C***/0000-0001-5227-7894

CONSPECTUS:The discovery and creation of new forms of carbon have always transformed the scientific *** example,the discoveries of fullerenes,carbon nanotubes(CNTs),and graphenes have opened doors to the science of nanometersized carbon allotropes,otherwise known as *** then,researchers worldwide have unveiled their outstanding physical and chemical properties,and a number of applications and technologies have arisen in not only materials science but also biological research *** synthesis and study of this privileged class of“single-molecule”compounds has become one of the most engaging subjects in chemistry and holds huge promise to establish new fields in molecular ***,there have been huge gaps between established small-molecule chemistry and nanocarbon *** the particular case of CNTs,it is still not possible to access structurally uniform *** a wide range of synthetic methods have been reported,CNTs are generally accessed as a mixture of various *** logical strategy to achieve full synthetic control over CNTs is to build up from a template molecule with structural precision(the so-called“growth-from-template”strategy),where a short CNT segment molecule represents an initial synthetic *** this end,organic synthesis techniques are our most powerful tools to synthesize short CNT segments such as carbon nanorings and carbon *** Account highlights our 16-year campaign in the synthesis and application of carbon nanorings and carbon *** first topic is the synthesis of carbon nanorings(cycloparaphenylenes)as substructures of *** second topic is the synthesis of armchair and zigzag carbon nanobelts,which consist solely of fully fused hexagonal rings and provide a continuous double-stranded cylindrical *** third topic is the synthesis of methylene-bridged cycloparaphenylene,an aromatic belt containing nonhexagonal rings,in which the cyclic paraphenylene chain i

关键词： rings synthesis hexagonal