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Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

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Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： Shi-liang Xu Ying-Nan Zhao Yao Yu Qi Yang li-Hua Na Heng liu chun-Yu Zhang Xue-Quan Zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in *** catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of ***,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene *** characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer *** resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

Microstructure, texture and tensile properties of Mg-1 OSn alloys extruded in different conditions

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Journal of Central South University 2013年第7期20卷 1786-1791页

作者： CHENG Wei-li li Jia-wei QUE Zhong-ping ZHANG Jin-shan XU chun-xiang liANG Wei YOU Bong-Sun PARK Sung Soo Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education Taiyuan University of Technology Taiyuan 030024 China School of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 China Korea Institute of Materials Science Changwon 641-831 Korea Ulsan National Institute of Science and Technology Ulsan 689-798 Korea

Indirect extrusion of Mg-10%Sn (mass fraction) alloys was performed at three different working temperatures. The effect of working temperature on the microstructure, texture and tensile properties of the extruded alloys was investigated by optical microscope (OM), scanning electronic microscope (SEM), X-ray diffraction (XRD) and a standard universal testing machine. Grain size, area fraction of second phase particles and texture of the alloys are found to be significantly influenced by working temperature. The grain size refinement is greatly dependent on processing conditions with the low working temperature being the most effective. While the high working temperature results in a coarser grain size and a stronger fiber texture and the reason for this phenomenon was examined in terms of second phase particle, grain type and dynamic recrystallization mechanism. Tested in the different conditions, the tensile strengths of the Mg-10Sn alloys extruded at the high working temperature are remarkably better than those of the other studied alloys. This significant improvement in tensile properties is mainly due to the particle strengthening and texture strengthening resulted from the more and finer primary dispersed particles and stronger texture, respectively.

关键词： magnesium alloy extrusion microstructure texture tensile properties

Response functions of a 4π summing gamma detector in β-Oslo method

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Nuclear Science and Techniques 2022年第6期33卷 9-17页

作者： Guo-chun Yang Lei-Ming Hua Fei Lu Jun Su Zhi-Hong li Shi-Lun Jin Yang-Ping Shen Bing Guo Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China China Institute of Atomic Energy P.O.Box 275(10)Beijing 102413China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China

The response functions of a 4π summing BGO detector were established using extensive experimental measurements and GEANT4 simulation. The partial and total efficiencies for all components of the γ-ray interaction with the BGO detector were also measured. These response functions and efficiencies will be used in the β-Oslo method experiments to study the neutron capture cross sections of radioactive heavy ions. The application of the response functions of the BGO detector under simulated continuum γ-rays and source measurement γ-rays proves that the method and response functions are reliable.

关键词： 4πSumming BGO detector γ-Ray spectrum Energy resolutions GEANT4 simulation

Microstructure and properties of Al–7Si–0.6Mg alloys with different Ti contents deposited by wire arc additive manufacturing

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Rare Metals 2021年第9期40卷 2530-2537页

作者： Cheng-De li Hui-Min Gu Wei Wang Shuai Wang ling-ling Ren Yu-chun Zhai Zhen-Biao Wang Zhu Ming School of Metallurgy Northeastern UniversityShenyang 110006China Research Laboratory of WAAM Process Inner Mongolia Metal Material Research InstituteNingbo 315100China Technology Department North East Industrial Materials and Metallurgy Co.Ltd.Fushun 113200China

Numerous studies have addressed the advantages of wire arc additive manufacturing for manufacturing aluminum alloys. However, the role of Ti content in aluminum alloys has rarely been discussed. Herein, the effect of Ti content on the microstructure and properties of Al–7 Si–0.6 Mg alloys was studied. The alloys were deposited via wire arc additive manufacturing and were examined through optical microscopy(OM), scanning electron microscopy(SEM), and electronic universal testing. The results show that the increase of Ti content gradually promotes the increase of the secondary dendrite arm spacing and also has an increasing tendency to form pores defect in the as-deposited alloys. The change of titanium content also affects the difference between horizontal and vertical direction properties of the alloy. The alloy with a Ti content of 0.112 wt% exhibits the best comprehensive properties. There is no difference in its horizontal and vertical direction properties. The tensile strengths, yield strengths, and elongation of this alloy(T6) along the vertical and horizontal axis are 356 and 355 MPa, 307 and308 MPa, and 8.5% and 8.0%, respectively.

关键词： Wire arc additive manufacturing Al–7Si–0.6Mg alloy Microstructure and properties Titanium

Ultrahard X-ray multifunctional application beamline at the SSRF

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Nuclear Science and Techniques 2024年第6期35卷 14-25页

作者： Ke Yang Zhao-Hui Dong chun-Yin Zhou Zi-Long Zhao Dong-Xu liang Sai-Chao Cao Ai-Guo li Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

The ultrahard X-ray multifunctional application beamline(BL12SW)is a phase-II beamline project at the Shanghai Syn-chrotron Radiation *** primary X-ray techniques used at the beamline are high-energy X-ray diffraction and imaging using white and monochromatic *** main scientific objectives of ultrahard X-ray beamlines are focused on two research *** is the study of the structural properties of Earth’s interior and new materials under extreme high-temperature and high-pressure conditions,and the other is the characterization of materials and processes in near-real service *** beamline utilizes a superconducting wiggler as the light source,with two diamond windows and SiC discs to filter out low-energy light(primarily below 30 keV)and a Cu filter assembly to control the thermal load entering the subsequent optical *** beamline is equipped with dual *** first was a meridional bending Laue monochromator cooled by liquid nitrogen,achieving a full-energy coverage of 30-162 *** second was a sagittal bending Laue monochromator installed in an external building,providing a focused beam in the horizontal direction with an energy range of 60-120 *** were four experimental hutches:two large-volume press experimental hutches(LVP1 and LVP2)and two engineering material experimental hutches(ENG1 and ENG2).Each hutch was equipped with various near-real service conditions to satisfy different *** example,LVP1 and LVP2 were equipped with a 200-ton DDIA press and a 2000-ton dual-mode(DDIA and Kawai)press,***1 and ENG2 provide in situ tensile,creep,and fatigue tests as well as high-temperature *** June 2023,the BL12SW has been in trial *** is expected to officially open to users by early 2024.

关键词： Shanghai Synchrotron Radiation Facility Ultrahard X-ray High energy diffraction High energy imaging Engineering materials Earth science

Comparison between Ophthalmologists and Community Health Workers in Screening of Shallow Anterior Chamber with Oblique Flashlight Test

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Chinese Medical Sciences Journal 2010年第1期25卷 50-52页

作者： Yusoh Nuriyah Xue-tao Ren li Jiang xi-pu liu Yan-hong Zou Department of Ophthalmology Sekwa Eye Hospital Beijing 100088 China Department of Ophthalmology First Hospital of Tsinghua University Beijing 100016 China

Objective To study the agreement between ophthalmologists and community health workers in detecting shallow anterior chamber with oblique flashlight test. Methods Totally 425 subjects were given an eye examination in a community health center. The anterior chamber depth of each subject was examined by one ophthalmologist and two trained community health workers (one nurse and one non-professional health worker) using oblique flashlight test. Inter-observer agreement was determined using the weighted kappa statistic. Results Among the enrolled subjects,148 (35%) were male and 277 (65%) were female. Good agreement was noted in all the three observers. The comparison between the ophthalmologist and the nurse showed a kappa statistic of 0.42 for both eyes (Plique flashlight test may be used as an applicable tool by trained community health workers for screening of shallow anterior chamber and play a role in blindness prevention in community.

关键词： glaucoma shallow anterior chamber oblique flashlight test

The interaction between the membrane-proximal external region and the N-trimer region of HIV-1 gp41: Involvement in viral fusion

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Chinese Science Bulletin 2009年第10期54卷 1707-1712页

作者： li Jing LU Lu WU Fan CHEN xi NIU Ben JIANG ShiBo CHEN YingHua Laboratory of Immunology Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China Beijing Key Laboratory for Protein Therapeutics Beijing 100084 China Laboratory of Viral Immunology Lindsley F. Kimball Research Institute New York Blood Center NY 10065 USA

The membrane proximal external region (MPER) of gp41 is extremely conserved among diverse HIV-1 variants, implying its important role in viral infection. Interestingly, two of the most broadly neutralizing antibodies, 2F5 and 4E10, specifically recognize this region. Our previous study demonstrated that the antigenicity and immunogenicity of 4E10 epitope are affected by remodeling gp41 fusion core, suggesting that the MPER may be associated with gp41 core and involved in gp41-mediated membrane fusion. Here we measured the binding activity of 4E10 epitope peptide (D4E10P) with various gp41 core-derived peptides and found that the N-trimer region in a construct designated N-trimer-6HB interacted significantly with D4E10P. Using N-trimer-6HB to screen a phage library, we identified a motif (WF) located in 4E10 epitope that may play a certain role in the interaction of gp41 MPER with the N-trimer in gp41 fusion core and, we thus speculated upon the potential involvement of MPER in the fusion process between viral envelope and target cell membrane.

关键词： gp41 病毒感染外部区域相互作用三聚体膜融合 HIV 抗原表位

Influence of Sb on the Scintillation Properties of Lead Tungstate Crystal

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Chinese Physics Letters 1999年第10期16卷 761-763页

作者： liU xian-cai HU Guan-qin FENG xi-qi li Pei-jun ZHANG Ming-rong XU li YIN Zhi-wen Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050

Sb-doped lead tungstate(PWO)crystals were grown and *** measurements of Sb content in crystals indicated that the segregation coefficient of Sb in PWO is about *** with a little Sb^(3+)introduced into PWO crystal,the transmission,especially the light yield was enhanced ***,after the Sb-doped PWO crystals were annealed,not only the fast component still remained a high percentage but also the radiation hardness was improved *** main reason may be that Sb-doping can compensate the composition deficiency and then reduce the density of hole centers such as Pb^(3+)and O^(-).

关键词： centers doping annealed

A stable and efficient La-doped MIL-53(Al)/ZnO photocatalyst for sulfamethazine degradation

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Journal of Rare Earths 2022年第4期40卷 595-604,I0004页

作者： Qiuming Wei Wei li chun Jin Yasi Chen linlin Hou Zhiliang Wu Zhongliang Pan Qinyu He Yinzhen Wang Dingyuan Tang Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication EngineeringSouth China Normal UniversityGuangzhou 510006China Guangdong Engineering Technology Research Center of Efficient Green Energy and Environmental Protection Materials Guangzhou 510006China School of Electrical and Electronic Engineering Nanyang Technological University639798Singapore

Photocatalytic technology can solve various environmental pollution problems,especially antibiotic pollution.A novel La-doped MIL-53(Al)/ZnO composite material was successfully synthesized by a combination of hydrothermal method and calcination,showing high photocatalytic degradation percent of sulfamethazine(SMT).The 2 mol%La MIL-53(Al)/ZnO photocatalyst shows the highest degradation efficiency toward SMT(92%)within 120 min,which is 4.1 times higher than pure ZnO(increased from 18%to 92%).In addition,the degradation analysis of SMT by high performance liquid chromatography proves that the products are CO_(2) and H_(2)*** improved photocatalytic activity is mostly caused by the following factors.(1)Doping La ions can decrease the band gap of ZnO,enhance light response,and effectively enhance the separation rate of photo-generated holes and electrons.(2)MIL-53(Al)can adsorb SMT and promote the separation of *** work shows that the synthesized La-doped MIL-53(Al)/ZnO photocatalyst is expected to be used as a green and effective method for treatment of environment water pollution.

关键词： Sulfamethazine Photocatalytic degradation Zinc oxide Lanthanum doping Rare earths