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Polymerization of Methyl Methacrylate by Diisopropylamido bis(methylcyclopentadienyl) ytterbium Complex

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Chinese Chemical Letters 1997年第7期8卷 637-638页

作者： Mao, LS xue, Mq Shen, q SUZHOU UNIV DEPT CHEMSUZHOU 215006PEOPLES R CHINA

It was first found that diisopropylamido bis(methylcyclopentadienyl) ytterbium complex (MeCp)(2)YbN(i-Pr)(2)(THF) exhibits extremely high catalytic activity in the polymerization of methyl methacrylate. The reactions can be carried out over a quite broad range of polymerization temperatures from -78 degrees C to 40 degrees C. The results of gPC (gel permeation chromatography) indicate that the molecular weight distribution (Mw/Mn) becomes broad with the increase of temperature.

关键词： THF Polymerization of Methyl Methacrylate by Diisopropylamido bis methylcyclopentadienyl ytterbium Complex

N=2a=1 supersymmetric KdV equation and its Darboux-B?cklund transformations

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Communications in Theoretical Physics 2024年第11期76卷 12-19页

作者： XiaoXia Yang Lingling xue q P Liu School of Mathematical Sciences Capital Normal UniversityBejing 100048China Department of Applied Mathematics Ningbo UniversityNingbo 315211China Department of Mathematics China University of Mining and TechnologyBeijing 100083China

In this paper,we study the N=2a=1 supersymmetric KdV *** construct its Darboux transformation and the associated B?cklund ***,we derive a nonlinear superposition formula,and as applications we calculate some solutions for this supersymmetric KdV equation and recover the related results for the Kersten-Krasil'shchik coupled KdV-mKdV system.

关键词： B?cklund transformations integrable systems Darboux transformations nonlinear superposition formula supersymmetric integrable systems

Shennan Road and the modernization of Shenzhen architecture

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Frontiers of Architectural Research 2020年第2期9卷 437-449页

作者： Cong Sun Charlie q.L.xue Department of Architecture and Civil Engineering City University of Hong KongHong KongChina

Shenzhen exemplifies the rapid development of urban planning and construction in *** the last 40 years,many representative urban spaces and buildings have been built on Shennan Road,the city’s main eastewest thoroughfare,which has witnessed the formation of a multicenter structural layout and the miraculous expansion of the *** iconic buildings were designed by Hong Kong or foreign *** continuous development along Shennan Road not only symbolizes the fruits of the reform and opening up policies of Shenzhen and even China,but also reflects the modern architectural history in *** study uses historical research methods to review the changes in the urban fabric and the design trends,as seen in representative buildings along Shennan Road in different *** addition to the transition path of the city center,the unique role of streets and buildings in the development of the urban structure is analyzed,and other urban functions and symbolic meanings are *** work contributes to the history and theory of the modernization of contemporary Chinese architecture.

关键词： Shenzhen architecture Shennan road Contemporary Chinese architecture Foreign design Rapid urbanization

The W-11-4A Platform Comprehensive Strength Monitoring System

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China Ocean Engineering 1998年第2期13卷 135-146页

作者： Shen, ZH Li, H xue, YI Chen, JC Zhao, q Chinese Acad Sci Inst Mech Beijing 100080 Peoples R China Louisiana Tech Univ Appl & Computat Anal & Modeling Program Ruston LA 71272 USA Acad Sinica S China Sea Inst Oceanol Guangzhou 510301 Peoples R China

A comprehensive strength monitoring system used on a fixed jacket platform is presented in this paper. The long-term monitoring of W-11-4A platform achieved. Structural responses (strain and acceleration) at selected locations, as well as associated environmental parameters, have been obtained. The emphasis of the paper is placed on the system design, and the instrumentation and operation methodology employed in the monitoring of the structural responses. The performance of the system and the characteristic results obtained during its 13-month operation are also summarized.

关键词： monitoring techniques comprehensive strength monitoring structural responses waterproof strain transducers underwater instrumentation techniques

Template-free Fabrication and Luminescent Characterization of Highly Uniform and Monodisperse Y_2O_2S:Sm^(3+) Hollow Submicrospheres

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Journal of Materials Science & Technology 2012年第7期28卷 666-672页

作者： S.q. Deng Z.P. xue Y.H. Yang q. Yang Y.L. Liu Department of Chemistry Jinan University Guangzhou 510632 China

Well dispersed and homogeneous Y2O2S：Sm3＋ hollow submicrospheres were successfully achieved by a template- free solvothermal method combining with a postcalcining process. The crystalstructure and particle morphology were investigated by the X-ray diffraction （XRD）, Fourier transform infrared （FT-IR） spectra, scanning and transmission electron microscopy （SEM and TEM）, respectively. A possible growth mechanism was proposed to reveal the formation process. Luminescence properties of the Y202S：Sm3＋ long-lasting phosphor were an- alyzed by measuring the excitation spectra, emission spectra, afterglow decay curve and thermoluminescence curve. The excitation spectra indicated that the phosphor could be excited effectively by the ultraviolet-light emitting diode （UV-LED） or blue LED, and the emission spectra showed that the phosphor could emit red light from 600 to 650 nm.

关键词： Yttrium oxysulfide Hollow submicrosphere Luminescence Long-lasting phosphor

Effect of Mo on microstructural characteristics and coarsening kinetics of γ' precipitates in Co–Al–W–Ta–Ti alloys

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Journal of Materials Science & Technology 2018年第5期34卷 799-805页

作者： H.J.Zhou F.xue H.Chang q.Feng State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing National Center for Materials Service Safety University of Science and Technology Beijing

The solvus temperature,volume fraction,coarsening behavior of γ＇ precipitates and the partitioning behavior of alloying elements as well as lattice misfit of γ/γ＇ phases influence the creep behavior of Ni-and Co-base ***,few investigations about the microstructural characteristics and the coarsening behavior of γ＇ precipitates were reported in multicomponent novel Co-base superalloys during thermal *** alloys containing different contents of molybdenum and tungsten have been investigated to explore the effect of molybdenum on γ＇ solvus temperature,γ ＋γ＇ microstructure and γ＇ coarsening in Co–Al–W–Ta–Ti-base *** results showed that the γ＇ solvus temperature decreases with the addition of *** addition reduces the Y＇ volume fractions after aging above 1000℃,but results in negligible influence on the γ＇ volume fractions aging at 900℃.Meanwhile,γ＇ coarsening is controlled by diffusion in experimental alloys after aging at 900℃ and 1000℃,and the kinetics of Y＇growth in experimental alloys are consistent with the predictions of LSW theory.

关键词： Cobalt alloys Molybdenum Coarsening Microstructure

groupⅢmetabotropic glutamate receptors and drug addiction

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Frontiers of Medicine 2013年第4期7卷 445-451页

作者： Limin Mao Minglei guo Daozhong Jin Bing xue John q.Wang Department of Basic Medical Science School of MedicineUniversity of Missouri-Kansas CityKansas CityMO 64108USA

Neuroadaptations of glutamatergic transmission in the limbic reward circuitry are linked to persistent drug *** data have demonstrated roles of ionotropic glutamate receptors and groupⅠandⅡmetabotropic glutamate receptors(mgluRs)in this *** evidence also identifies gαi/o-coupled groupⅢmgluRs(mgluR4/7/8 subtypes enriched in the limbic system)as direct substrates of drugs of abuse and active regulators of drug ***-and heteroreceptors of mgluR4/7/8 reside predominantly on nerve terminals of glutamatergic corticostriatal and gABAergic striatopallidal pathways,*** presynaptic receptors regulate basal and/or phasic release of respective transmitters to maintain basal ganglia *** response to operant administration of common addictive drugs,such as psychostimulants(cocaine and amphetamine),alcohol and opiates,limbic groupⅢmgluRs undergo drastic adaptations to contribute to the enduring remodeling of excitatory synapses and to usually suppress drug seeking *** a result,a loss-of-function mutation(knockout)of individual groupⅢreceptor subtypes often promotes drug *** review summarizes the data from recent studies on three groupⅢreceptor subtypes(mgluR4/7/8)expressed in the basal ganglia and analyzes their roles in the regulation of dopamine and glutamate signaling in the striatum and their participation in the addictive properties of three major classes of drugs(psychostimulants,alcohol,and opiates).

关键词： groupⅢmetabotropic glutamate receptors cocaine amphetamine alcohol opiate

Performing arts buildings in Taiyuan:Cultural history buildings in a second-tier Chinese city

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Frontiers of Architectural Research 2019年第2期8卷 215-228页

作者： Yingbo Xiao Yan Wan Charlie q.L.xue Department of Architecture and Civil Engineering City University of Hong KongHong KongChina

In the twenty-first century,Chinese cities tend to rely on cultural megastructures to define their new districts and reflect their aspirations.A grand theater,which is a complicated building type in terms of technology and has a striking image,is a central attraction and the focus of a new *** paper focuses on Taiyuan City,a second-tier Chinese city with a brilliant history that has been gradually reduced to *** paper aims to reveal the relationship among productivity,urban development,and theater construction in different historic periods;highlights the initiation,design,and implication of the latest grand theater designed by a French firm;and investigates the city and its performing arts spaces,stakeholders,and various forces that make the theater and its urban *** affective forces may be typical in Central China,which is a generally backward area compared with the entire *** paper presents proper descriptors for performing arts buildings in Taiyuan for three generations,and the lessons from Taiyuan can provide references for other cities that face similar problems and challenges.

关键词： The Shanxi grand theatre Performing art space Importation of design International architecture

Evolution of microstructure and phase composition of Ti-3Al-5Mo-4.5V alloy with varied β phase stability

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Journal of Materials Science & Technology 2018年第12期34卷 2325-2330页

作者： q.xue Y.J.Ma J.F.Lei R.Yang C.Wang School of Metallurgy Northeastern University Institute of Metal Research Chinese Academy of Sciences

The microstructure evolution and phase composition of an α+β titanium alloy, Ti-3Al-5Mo-4.5V(wt.%),have been investigated. Electron probe micro analysis(EPMA) quantitative results manifest that the stability of β phase decreases with increasing quenching temperature, which is influenced by the significant variation of β-stabilizing elements concentration. Detailed microstructure analysis shows that the β→ωphase transformation does occur when quenching at 750℃ and 800 ℃. The ω-reflections change from incommensurate ω-spots(750 ℃) to ideal ω-spots(800 ℃) as the β stability of the alloy decreases. Further the decrease of β phase stability encourages the formation of athermal α " martensite, which has the following orientation relationships: [111]β//[110]α",[100]p//[100]α " and [-110]p//[00-1]α" with respect to the β matrix.

关键词： Dual-phase titanium alloy β phase stability ω phase α" martensite Microstructure