检索结果-南通市图书馆

Science china {1. 2009年第11期52卷 1961-1968页

作者： ren jie1.2,wang bingwu1.& chen zhida1.1.beijing national Laboratory for molecular sciences,state key Laboratory of rare earth materials chemistry and applications,college of chemistry and molecular engineering,peking university,beijing 1.0871.china 2 college of Science,Hebei university of Science and Technology,Shijiazhuang 050018,china 1. beijing {1. Laboratory for molecular sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing 100871 China 2. college of Science Hebei University of Science and Technology Shijiazhuang 050018 China

The magnetic coupling interactions of the nitronyl nitroxide radicals bound to diamagnetic(YⅢ) and paramagnetic(GdⅢ) rare {1. ions in two model magnetic systems based on novel rare {1. organic radical complexes Ln(hfac)3(NITPhOCH3)2(Ln=YⅢ 1.GdⅢ 2;hafc = hexafluoroacetylacetonate;NIT-PhOCH3 = 4'-methoxyo-phenyl-4,4,5,5-tetramethylimidazoline-1.oxyl-3-oxide) have been investigated by density functional theory(DFT).The magnetic coupling mechanisms were also explored from the viewpoint of molecular orbital and spin density *** calculations show that the empty 4d-orbitals of YⅢ and 5d-orbitals of GdⅢ play an important role in the antiferromagnetic coupling between the two nitronyl nitroxide radical ligands,and that the ferromagnetic coupling between the GdⅢ ion and the radical magnetic centers can be attributed to the nearly complete localization of the isotropic 4f-shell and singly occupied magnetic orbital(π) of the nitronyl nitroxide.

关键词： magnetic coupling density functional theory rare earth ion gadolinium(Ⅲ) complexes yttrium(Ⅲ) complexes

Significant effect of ordered micro-domain on cell boundary phase distribution and demagnetization curve squareness of Sm_(2)Co_(1.)-type magnet

在线全文

学校读者我要写书评

暂无评论

rare Metals 2024年第4期43卷 1724-1735页

作者： Zhuang Liu Hai-chen Wu Chao-Yue Zhang Chao-Qun Zhu Guo-Xin chen Huan-Ming Lu ren-jie chen Aru Yan CISRI&NIMTE Joint Innovation Center for rare {1. Permanent Magnets Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China university of Chinese Academy of {1. Beijing100049China Analytical Center Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China

Cu-rich cell boundary phase is difficult to precipitate evenly,resulting in a generally poor demagnetization curve squareness for Fe-rich Sm_(2)Co_(1.)-type magnet,which is a {1. factor limiting the further improvement of magnetic energy *** this study,we report that nanoscale strip-like ordered micro-domains distributed in1.7H disordered matrix phase of the solid solution precursor is a new factor significantly affecting the precipitation and distribution of the cell boundary *** strip-like and continuous micro-twin structure with twin boundaries neatly perpendicular to the C-axis is observed after sintering *** solution treatment,sequential and long strip-like micro-twins gradually transform into disordered state along the basal plane,forming narrow disordered 1.7H(TbCu_(7)-type structure)phase between the separated strip-like ordered *** disordering transformation takes place via broken down of the long strip-like ordered micro-domains,which is accomplished by narrowing along the width direction followed by reduction of the ***,a new model revealing the effect of the ordered micro-domains on the formation of the cell boundary phase is *** boundaries enriched in Cu have already existed in the precursor with long strip-like ordered ***,the Cu-rich cell boundary phase acting as strong pinning centers cannot be precipitated homogeneously and distributed continuously after aging,resulting in a poor demagnetization curve squareness of Sm_(2)Co_(1.)-type *** results indicate that significant broken down of the nanoscale ordered micro-domains in solution precursor is the {1. factor improving the distribution of cell boundary phase in Sm_(2)Co_(1.)-type magnets.

关键词： Sm_(2)Co_(1.) magnets Solution precursor Ordered micro-domains Disordering transformation Cellular structure

Theoretical study on potential energy curves and spectroscopy properties of ground and low-lying excited electronic states of BrCl^+

在线全文

学校读者我要写书评

暂无评论

Science china {1. 2008年第6期51卷 521-528页

作者： wang MingWei wang bingwu chen zhida beijing {1. Laboratory for molecular sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

The calculations on the potential energy curves and spectroscopic constants of the ground and low-lying excited states of BrCl^+, one of the important {1. ions in environment science, have been performed by using the multireference configuration interaction method at high level of theory in quantum chemistry. Through analyses of the effects of the spin-orbit coupling interaction on the electronic structures and spectroscopic properties, the multiconflguration characteristic of the X^2Π ground state and low-lying excited states was established. The spin-orbit coupling splitting energy of the X^2 Π ground state was calculated to be 1.14 cm^(-1., close to the experimental value 2070 cm^(-1.. The spin-orbit coupling splitting energy of the ~2Π(II) exited state was predicted to be 766 cm^(-1.. The transition dipole moments and Frank-Condon factors of the 3/2(III)-X3/2 and 1.2(III)-1.2(I) transitions were estimated, and the radiative lifetimes of the two transitions were briefly discussed.

关键词： BrCl+ ab initio MRCI(SD)+Q method spin-orbit coupling low-lying excited state potential energy curves

Design,preparation,microstructure and mechanical property of the lightweight radiation-shielding Mg-Ta-Al composites basing differential temperature hot rolling

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2024年第6期12卷 2433-2446页

作者： Wenbo Luo Songya Feng Xiuzhu Han Li Zhou Qinke Kong Zhiyong Xue Jianzhao wang Mei Zhan Xianhua {1. Fusheng Pan Institute for Advanced materials North China Electric Power UniversityBeijing 102206China beijing Institute of Spacecraft System {1. Beijing 100094China Sinosteel Equipment&engineering Co Ltd.Beijing100080China state {1. Laboratory of Baiyunobo rare earth Resource Researches and Comprehensive Utilization Inner Mongolia 014030China School of materials Science Northwestern Polytechnical UniversityXi’an 710072China college of {1. Science and engineering Chongqing UniversityChongqing 400045China

A novel lightweight,radiation-shielding Mg-Ta-Al layered metal-matrix composite(LMC)was successful designed by doping the extremely refractory metal(Ta)into Mg *** Mg-based LMCs sheets shows excellent radiation-dose shield effect,about 1.5 krad·a^(−1.,which is about 1. times of traditional Mg alloy,while its surface density is only about 0.9 g·cm^(−2),reducing by 60%than that of pure *** quantitate relationship between radiation-dose and the materials’thickness was also confirmed to the logistic function when the surface density is in the range of 0.6-1.5 g·cm^(−2).Meantime,the rolling parameters,interface microstructure and mechanical properties in both as-rolled and annealing treated samples were *** sheets possess a special dissimilar atoms diffusion transitional zone containing an obvious inter-diffusion Mg-Al interface and the unique micro-corrugated Ta-Al interface,as well as a thin Al film with a thickness of about 1.μ*** special zone could reduce the stress concentration and enhance the st{1.gth of Mg-Ta-Al *** interface bonding st{1.gth reaches up to 54-76 *** ultimate tensile st{1.gth(UTS)and yield st{1.gth(TYS)of the Mg-Ta-Al sheet were high to 41. MPa and 263 MPa,respectively,along with an elongation of 5.8%.The molecular dynamics(MD)analysis results show that the two interfaces exhibit diffe{1.t formation mechanism,the Mg-Al interface primarily depended on Mg/Al atoms diffusion basing point defects movement,while the Ta-Al interface with a micro-interlock pining shape formed by close-packed planes slipping during high temperature strain-induced deformation process.

关键词： Dissimilar metals composites Mg based alloys Radiation shielding Hot rolling Lightweight

Strong metal-support interactions between highly dispersed Cu^(+) species and ceria via mix-MOF pyrolysis toward promoted water-gas shift reaction

在线全文

学校读者我要写书评

暂无评论

Journal of Energy chemistry 2024年第4期91卷 475-483页

作者： Xiao-chen Sun Xing-Chi Li Ze-Wei Xie chen-Yue Yuan De-Jiu wang Qian Zhang Xiao-Yu Guo Hao Dong Hai-Chao Liu Ya-Wen Zhang beijing {1. Laboratory for molecular sciences(BNLMS) State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China beijing {1. Laboratory for molecular sciences(BNLMS) College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China beijing {1. Laboratory for molecular sciences(BNLMS) State Key Laboratory for Structural Chemistry of Stable and Unstable SpeciesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The modulation of metal-support interfacial interaction is significant but challenging in the design of high-efficiency and high-stability supported ***,we report a synthetic strategy to upgrade Cu-CeO_(2)interfacial interaction by the pyrolysis of mixed metal-organic framework(MOF)*** obtained highly dispersed Cu/CeO_(2)-MOF catalyst via this strategy was used to catalyze water-gas shift reaction(WGSR),which exhibited high activity of 40.5μmolCOgcat^(-1..s^(-1.at 300℃and high stability of about 1.0 *** on comprehensive studies of electronic structure,pyrolysis strategy has significant effect on enhancing metal-support interaction and then stabilizing interfacial Cu^(+)species under reaction *** Cu^(+)species and generated oxygen vacancies over Cu/CeO_(2)-MOF catalyst played a key role in CO molecule activation and H2O molecule dissociation,*** collaborated closely and then promoted WGSR catalytic performance in comparison with traditio nal supported *** study shall offer a robust approach to harvest highly dispersed catalysts with finely-tuned metal-support interactions for stabilizing the most interfacial active metal species in diverse heterogeneous catalytic reactions.

关键词： Cu-based catalyst MOF derivative Water-gas shift reaction Metal-support interaction

Divalent Ytterbium Iodide Supported by β-Diketiminato Based Tridentate Ligand: Synthesis, Structure and Small Molecule Activation

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of chemistry 2020年第3期38卷 247-253页

作者： Xiaojuan Liu Li Xiang chen {1. bingwu {1. Xuebing Leng Yaofeng chen state {1. Laboratory of Organometllic chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China Beiing national laboratory of {1. Science State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsCollege of Chemistry and Moleculor EngineeringPeking UniversityBeijing 100871Chino

Divalent ytterbium lodide[LYb(μ-I)(THF)]2(1.L=[MeC(NDIPP)CHC(Me)NCH2CH2NMe2]^-,DIPP=2,6-(iPr)2C6H3)was synthesized and its reactivity was *** 1.was synthesized by salt metathesis of Ybl2(THF)2 with the potassium salt of ligand(KL)in high *** the reactions with trimethylsil azide,azobenzene,sulfur and diphenyl disufide,complex 1.acts as a 2e *** the reaction with CO2,the central carbon atom ofβ-diketiminato backbone in 1.nuclephilcally attacks the CO2 molecule to give a divalent ytterbium carboxylate.

关键词： backbone potassium azide

Efficient Spin-Flip between Charge-Transfer states for High-Performance Electroluminescence, without an Intermediate Locally Excited state

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research 2024年第1期2023卷 339-349页

作者： Donghai Zhang Shanshan Jiang Xiaodong Tao Fulin Lin Lingyi Meng Xu-Lin chen Can-Zhong Lu state {1. Laboratory of Structural chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002China Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of china FuzhouFujian 350108China Xiamen key Laboratory of {1. earth Photoelectric Functional materials Xiamen Institute of Rare Earth MaterialsHaixi InstitutesChinese Academy of SciencesXiamenFujian 361021China university of Chinese Academy of {1. Beijing 100049China

Thermally activated delayed fluorescence(TADF)materials with both high photoluminescence quantum yield(PLQY)and fast reverse intersystem crossing(RISC)are strongly desired to realize efficient and stable organic light-emitting diodes(OLEDs).Control of excited-{1. dynamics via molecular design plays a central role in optimizing the PLQY and RISC rate of TADF materials but remains ***,3 TADF emitters possessing similar molecular structures,similar high PLQYs(89.5%to 96.3%),and approximate energy levels of the lowest excited singlet {1.s(S_(1.),but significantly different spin-flipping RISC rates(0.03×1.^(6) s^(−1. vs.2.26×1.^(6) s^(−1.)and exciton lifetime(297.1.to 332.8μs vs.6.0μs)were systematically synthesized to deeply investigate the feasibility of spin-flip between charge-transfer excited {1.s(^(3)CT–^(1.CT)transition.

关键词： transition lifetime desired

Manipulating guest-responsive spin transition to achieve switchable fluorescence in a Hofmann-type framework

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science china {1. 2024年第10期67卷 3339-3346页

作者： Xue-Ru Wu Shu-Qi Wu Zhi-Kun Liu Ming-Xing chen Jun Tao Osamu Sato Hui-Zhong Kou engineering Research Center of Advanced {1. earth materials(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China Institute for materials {1. and engineering&IRCCS Kyushu University744 MotookaNishi-kuFukuoka 819-0395Japan key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical EngineeringLiangxiang CampusBeijing Institute of TechnologyBeijing 102488China Analytical Instrumentation Center College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The change of fluorescence emission manipulated by spin state transition attracts considerable attention owing to its potential {1. in magneto-optical switching ***,we report two two-dimensional(2D)Hofmann-type spin crossover(SCO)metal-organic frameworks(MOFs)[Fe^(Ⅱ)(PNI)_(2){Ag^(Ⅰ)(CN)_(2)}_(2)]·CHCl_(3)(3Ag·CHCl_(3))and[FeⅡ(PNI)_(2){AuⅠ(CN)_(2)}_(2)]·CHCl_(3)(3Au·CHCl_(3))based on the fluorescent ligand N-(4-pyridylmethyl)-1.8-naphthalimide(PNI).Both complexes exhibit interesting SCO behaviors switched by guest solvent molecules,namely three-step transitions for the solvated complexes and complete onestep hysteretic SCO for the desolvated ones,verified by temperature-dependent magnetic susceptibility measurements,Mossbauer spectra,structural analyses,and differential scanning calorimetry ***,temperature-dependent fluorescence spectra exhibit double peaks(monomer and excimer emission)with both emission peaks change consistent with the change in SCO properties during the solvent molecule *** this study,we integrated guest-responsive SCO behavior into MOFs to manipulate the multistability of spin state and fluorescence switching,providing a rational strategy for the development of stimuli-responsive multifunctional materials.

关键词： spin crossover fluorescence multifunctional materials metal-organic frameworks Hofmann-type

在线全文

学校读者我要写书评

暂无评论

Biomarkers of aging

Science china(Life {1.) 2023年第5期66卷 893-1066页

作者： Aging Biomarker Consortium Hainan Bao Jiani Cao Mengting chen Min chen Wei chen Xiao chen Yanhao chen Yu chen Yutian chen Zhiyang chen Jagadish K Chhetri Yingjie Ding Junlin Feng Jun Guo Mengmeng Guo Chuting He Yujuan Jia Haiping Jiang Ying Jing Dingfeng Li Jiaming Li Jingyi Li Qinhao Liang Rui Liang Feng Liu Xiaoqian Liu Zuojun Liu Oscar Junhong Luo Jianwei Lv Jingyi Ma Kehang Mao Jiawei Nie Xinhua Qiao Xinpei Sun Xiaoqiang Tang Jianfang wang Qiaoran wang Siyuan wang Xuan wang Yaning wang Yuhan wang Rimo Wu Kai Xia Fu-Hui Xiao Lingyan Xu Yingying Xu Haoteng Yan Liang Yang Ruici Yang Yuanxin Yang Yilin Ying Le Zhang Weiwei Zhang Wenwan Zhang Xing Zhang Zhuo Zhang Min Zhou Rui Zhou Qingchen Zhu Zhengmao Zhu Feng Cao Zhongwei Cao Piu Chan Chang chen Guobing chen Hou-Zao chen Jun chen Weimin Ci Bi-Sen Ding Qiurong Ding Feng Gao Jing-Dong JHan Kai Huang Zhenyu Ju Qing-Peng Kong Ji Li Jian Li Xin Li Baohua Liu Feng Liu Lin Liu Qiang Liu Qiang Liu Xingguo Liu Yong Liu Xianghang Luo Shuai Ma Xinran Ma Zhiyong Mao Jing Nie Yaojin Peng Jing Qu jie {21. Ruibao {21. Moshi Song Zhou Songyang Yi Eve Sun Yu Sun Mei Tian Shusen wang Si wang Xia wang Xiaoning wang Yan-Jiang wang Yunfang wang Catherine CL Wong Andy Peng Xiang Yichuan Xiao Zhengwei Xie Daichao Xu Jing Ye Rui Yue Cuntai Zhang Hongbo Zhang Liang Zhang Weiqi Zhang Yong Zhang Yun-Wu Zhang Zhuohua Zhang Tongbiao Zhao Yuzheng Zhao Dahai Zhu Weiguo Zou Gang Pei Guang-Hui Liu Aging Biomarker Consortium(ABC) Beijing 100101China CAS key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China state {1. Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Department of Dermatology Xiangya HospitalCentral South UniversityChangsha 410008China Hunan key Laboratory of Aging Biology Xiangya HospitalCentral South UniversityChangsha 410008China national Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha 410008China Clinic Center of Human Gene Research Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Hubei Clinical Research Center of Metabolic and Cardiovascular Disease Huazhong University of Science and TechnologyWuhan 430022China Hubei key Laboratory of Metabolic Abnormalities and Vascular Aging Huazhong University of Science and TechnologyWuhan 430022China Stem Cell Translational Research Center Tongji HospitalTongji University School of MedicineShanghai 200065China Department of Nuclear Medicine Daping HospitalThird Military Medical UniversityChongqing 400042China CAS key Laboratory of Nutrition Metabolism and Food SafetyShanghai Institute of Nutrition and HealthUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200031China Shanghai key Laboratory of Maternal Fetal Medicine Clinical and Translational Research Center of Shanghai First Maternity and Infant HospitalFrontier Science Center for Stem Cell ResearchShanghai Key Laboratory of Signaling and Disease ResearchSchool of Life Sciences and TechnologyTongji UniversityShanghai 200092China The Department of Endovascular Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China key Laboratory of Regenerative Medicine of Ministry of Education Institute of Ageing and Regenerative MedicineJ

Aging biomarkers are a combination of biological parameters to(i)assess age-related changes,(ii)track the physiological aging process,and(iii)predict the transition into a pathological *** a broad spectrum of aging biomarkers has been developed,their potential uses and limitations remain poorly *** immediate goal of biomarkers is to help us answer the following three fundamental questions in aging research:How old are we?Why do we get old?And how can we age slower?This review aims to address this ***,we summarize our current knowledge of biomarkers developed for cellular,organ,and organismal levels of aging,comprising six pillars:physiological characteristics,medical imaging,histological features,cellular alterations,{1. changes,and secretory *** fulfill all these requisites,we propose that aging biomarkers should qualify for being specific,systemic,and clinically relevant.

关键词： aging senescence biomarker clock

Gadolinium-doped mesoporous tungsten oxides:Rational synthesis,gas sensing performance,and mechanism investigation

在线全文

学校读者我要写书评

暂无评论

Nano Research 2023年第5期16卷 7527-7536页

作者： Yanyan Li keyu {1. Yan Liu Junhao Ma Yaozu Liao Haitao Yang Jinsheng {1.g Qin Yue Kaiping Yuan Yuan ren Yidong Zou Yonghui Deng Department of chemistry Department of Gastroenterology and HepatologyZhongshan HospitalZhangjiang Fudan International Innovation CenterState Key Laboratory of Molecular Engineering of PolymersiChEMShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200433China state {1. Laboratory for Modification of Chemical Fibers and Polymer materials Donghua UniversityShanghai 201620China School of materials Science and {1. Nanchang Hangkong UniversityNanchang 330063China Institute of Fundamental and Frontier sciences University of Electronic Science and Technology of ChinaChengdu 610051China Frontier Institute of Chip and System Fudan UniversityShanghai 200433China Henry-Fork School of Food sciences Shaoguan UniversityShaoguan 512005China

As a typical family of volatile toxic compounds,benzene derivatives are massive emission in industrial production and the automobile field,causing serious threat to human and *** reliable and convenient detection of low concentration benzene derivatives based on intelligent gas sensor is urgent and of great significance for environmental ***,through heteroatomic doping engineering,{1.-earth gadolinium(Gd)doped mesoporous WO_(3)with uniform mesopores(1..7–1..1.nm),tunable high specific surface area(52–55 m^(2)·g^(−1.),customized crystalline pore walls,was designed and utilized to fabricate highly sensitive gas sensors toward benzene derivatives,such as *** to the high-density oxygen vacancies(OV)and significantly increased defects(W^(5+))produced by Gd atoms doping into the lattice of WO_(3)octahedron,Gd-doped mesoporous WO_(3)exhibited excellent ethylbenzene sensing performance,including high response(237 vs.50 ppm),rapid response–recovery dynamic(1. s/25 s vs.50 ppm),extremely low theoretical detection limit of 24 *** in-situ diffuse reflectance inf{1.d Fourier transform and gas chromatograph-mass spectrometry results revealed the gas sensing process underwent a catalytic oxidation conversion of ethylbenzene into alcohol species,benzaldehyde,acetophenone,and carboxylate species along with the resistance change of the Gd-doped mesoporous WO_(3)based ***,a portable smart gas sensing module was fabricated and demonstrated for real-time detecting ethylbenzene,which provided new ideas to design heteroatom doped mesoporous materials for intelligent sensors.

关键词： mesoporous materials semiconductor metal oxides gadolinium doping gas sensor benzene derivatives