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International Journal of Minerals,Metallurgy and Materials 2019年第2期26卷 186-193页

作者： Peng Fei yi Min Cheng-jun Liu mao-fa Jiang Key Laboratory for Ecological Metallurgy of Multimetallic Mineral ((Ministry of Education)) School of Metallurgy Northeastern University Key Laboratory for Ecological Metallurgy of Multimetallic Mineral (Ministry of Education)

For the control of surface defects in interstitial-free(IF) steel, quantitative metallographic analyses of near-surface inclusions and surface liquid flow detection via the nail-board tipping method were conducted. The results show that, at casting speeds of 0.8 and 1.0 m/min, a thin liquid mold flux layer forms and non-uniform floating of argon bubbles occurs, inducing the entrainment and subsequent entrapment of the liquid flux; fine inclusion particles of Al_2O_3 can also aggregate at the solidification front. At higher casting speeds of 1.4 and 1.6 m/min, the liquid mold flux can be entrained and carried deeper into the liquid steel pool because of strong level fluctuations of the liquid steel and the flux. The optimal casting speed is approximately 1.2 m/min, with the most favorable surface flow status and, correspondingly, the lowest number of inclusions near the slab surface.

关键词： non-metallic inclusions distribution casting speed surface flow

Structural behavior of F-in mould flux melt of CaO-SiO2-Al2 O3-Na2O-CaF2 system

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Journal of Iron and Steel Research International 2017年第11期24卷 1152-1158页

作者： Qiang Gao yi Min Cheng-jun Liu mao-fa Jiang Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

The influence of fluorine on the structure of CaO Si（）e-Al2Oa Na2O-CaF2 continuous-casting-type slag was measured by Raman spectroscopy, and the degree of polymerization of mould flux and the structural behavior of F- in the melt were investigated by classifying and quantifying the structural species of F ions. The results exhibit that the main structural units of Si O tetrahedra are Q1, Q1 and Q2, and the actual measured number of non bridging oxygen ions in the [SiO4 ]-tetrahedra （denoted by NBO/T） in creases from 2. 73 to 3.44 with increasing the molar ratio of F to （F＋O）（denoted by XF/X（F-O ） from 0.06 to 0. 19. It means that the degree of polymerization o1 meh structure decreases with an increase in XE/X（F＋O）. In addition, most of F- ions were distributed in Si-O tetrahedra and Al-O tetrahedra. With increasing XF/X（F＋O）, the complex structural units Al-Otetrahedra are gradually replaced hy discrete structural units A1F4 because of the breakage of Al-O bonds in Al-Otetrahedra by F ions, and the SiO （bridging oxygen） bonds of SiO tetrahedra are broken to form [SiOnF1-n]-tetrahedra by F ions coordinating with Si4 ＋ .

关键词： Mould flux F- ion Melt structure Polymerization degree

In situ deformation behavior of TC21 titanium alloy with different α morphologies(equiaxed/lamellar)

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Rare Metals 2021年第5期40卷 1173-1181页

作者： Wei Long Mei-Gui Ou Xi-Qin mao yi-Long Liang College of Materials and Metallurgy Guizhou UniversityGuiyang 550025China Key Laboratory for Materials Structure and Strength of Guizhou Province Guizhou UniversityGuiyang 550025China National Local Joint Engineering Laboratory for High Performance Metal Structure Materials and Manufacturing Technology Guizhou UniversityGuiyang 550025China

To study the effect ofαphase morphology(equiaxedα(αE)/lamellarα(αL))on the in situ tensile behavior of TC21 alloy,the slip band,dislocation,crack initiation,and propagation were analyzed by scanning electron microscopy(SEM)with in situ tensile stage and transmission electron microscopy(TEM).The results show that the slip bands first concentrate in theαE phases and easily truncate at theα/βphase boundaries,whereas the slip bands move across theαlamellae in theαL *** are easily generated inαE orα/βphase boundaries with large plastic *** the quantity ofαL is more thanαE,the crack tip is more easily deflected atαphases orαclusters with different orientations,making the main crack propagation path more *** the volume fraction ratio ofαE toαL is~3:4,i.e.,the volume fraction ofαE is close to that ofαL,TC21 alloy exhibits better strength and slower crack propagation rate.

关键词： In situ tensile TC21 alloy Equiaxed Lamellar αPhase

Cable coupling response in metal cavity under X-ray irradiation

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Nuclear Science and Techniques 2024年第10期35卷 110-120页

作者： mao-Xing Zhang Lan-Feng Yuan Cui Meng yi-Nong Liu Department of Engineering Physics Tsinghua UniversityBeijing 100084China College of Electrical Engineering Zhejiang UniversityHangzhou 310007China Laboratory of Particle and Radiation Imaging Ministry of EducationBeijing 100084China

This study investigates the coupling response of cables inside a metal cavity under X-ray irradiation using the finite-difference time-domain method,particle simulation method,and transmission-line equation to solve the electromagnetic field inside the cavity and load voltage at the cable terminal under X-ray *** results show that under a strong ionizing radiation environment of 1 J/cm^(2),a strong electromagnetic environment is generated inside the *** cable shielding layer terminal couples a voltage of 15.32 V,whereas the core wire terminal couples a voltage of 0.31 *** strong X-ray irradiation,the metal cavity not only fails to provide electromagnetic shielding,but also introduces new electromagnetic *** study also provides a method for reducing the number of emitted electrons by adding low-Z materials,which can effectively reduce the coupled electric field and voltage.

关键词： Ionizing radiation Metal cavity System-generated electromagnetic pulse Transmission-line model

Geotechnical centrifuge model tests for explosion cratering and propagation laws of blast wave in sand

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第5期13卷 335-343页

作者： yi-kai FAN zu-yu CHEN Xiang-qian LIANG Xue-dong ZHANG Xin HUANG State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research Beijing 100044 China School of Transportation Science and Engineering Beihang University Beijing 100191 China

This paper presents the explosion cratering effects and their propagation laws of blast waves in dry standard sands using a 450 g-t geotechnical centrifuge *** centrifuge model tests were completed with various ranges of explosive mass,burial depth and centrifuge *** accelerometers were installed to record the acceleration response in *** dimensions of the explosion craters were measured after the *** results demonstrated that the relationship between the dimensionless parameters of cratering efficiency and gravity scaled yield is a power regression *** specific function equations were *** results are in general agreement with those obtained by other studies.A scaling law based on the combination of the π terms was used to fit the results of the ten model tests with a correlation coefficient of *** relationship can be conveniently used to predict the cratering effects in *** results also showed that the peak acceleration is a power increasing function of the acceleration *** empirical exponent relation between the proportional peak acceleration and distance is *** propagation velocity of blast waves is found to be ranged between 200 and 714 m/s.

关键词： Centrifuge model tests Explosion Craters Blast waves Sand

Two New Compounds from Melanosciadum pimpinelloideum H. Boiss

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Chinese Chemical Letters 2001年第4期12卷 333-334页

作者： yi ZHOU Guo Lin ZHANG Bo Gang LI Yao zu CHEN Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041 Chemistry Department Zhejiang UniversityHangzhou 310027 National Key Laboratory of Applied Organic Chemistry Lanzhou 730000

Two new compounds, melanochromone and 2-ethoxyl-2-(4-hydroxyphenyl)ethanol. were isolated from the whole plants of Melanosoiadum pimpinelloideum II. Boiss. The known compounds isolated were 1-(4-hydroxyphenyl)-1.2ethanediol. tymine. cimifugin, umtatin. bergenin. daucosterol and stigmasterol. Their structures were determined on the basis of spectral data.

关键词： Melanosciadum pimpinelloidum melanochromone 2-ethoxyl-2-(4-hydroxyphenyl) ethanol

Ag Nanowire-Ag Nanoparticle Hybrids for the Highly Enhanced Fluorescene Detection of Protoporphyrin IX Based on Surface Plasmon-Enhanced Fluorescence

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Chinese Journal of Chemistry 2016年第12期34卷 1321-1328页

作者： Yunjia Wang Xihong zu Guobin yi Hongsheng Luo Hailiang Huang Xuliang Song School of Chemical Engineering and Light Industry Guangdong University of Technology Guangzhou Guangdong 510006 China

In this study, we developed an approach to fabricate novel 1D Ag NWs-Ag NPs hybrid substrate for enhanced fluorescene detection of protoporphyrin 1X （PplX） based on surface plasmon-enhanced fluorescence. The Ag NWs-Ag NPs hybrid was synthesized by combining the hydrothermal method and self-assembly method with the asisstance of polyvinylpyrrolidone （PVP）. When the Ag NWs-Ag NPs hybrid was deposited on the glass substrate and employed as active substrate to detect PplX, the fluorescence intensity of PplX was enhanced greatly due to the coupling effect of localized surface plasmon-localized surface plasmon （LSP-LSP） and localized surface plasmon- surface plasmon propagation （LSP-SPP） which induced great enhancement of the electromagnetic field. Furthermore, the enhancement effect was approximately linear when the concentration of PpIX was ranged from 1×10^-7 mol/L to 2×10^-5 mol/L, and the photobleaching phenomenon of PplX was reduced greatly, indicating that the fab- ricated Ag NWs-Ag NPs hybrid substrate had well performance for PplX imaging. This work provides an effective approach to prepare highly sensitive and stable fluorescence enhancement substrate, and has great potential application in fluorescence imaging.

关键词： hybrid localized surface plasmon coupling surface plasmon resonance fluorescence enhancement

Effects of Mg2+ on the binding of the CREB/CRE complex:Full-atom molecular dynamics simulations

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Chinese Physics B 2019年第7期28卷 542-548页

作者： Song mao Shuai Wang Haiyou Deng Ming yi Department of Physics Huazhong Agriculture University

Metal ions play critical roles in the interaction between deoxyribonucleic acid(DNA) and *** experimental research has demonstrated that the Mg^2+ ion can affect the binding between transcription factor and *** our work,by full-atom molecular dynamic simulation, the effects of the Mg^2+ ion on the cyclic adenosine monophosphate(cAMP)response element binding protein(CREB)/cAMP response elements(CRE) complex are *** is illustrated that the number of hydrogen bonds formed at the interface between protein and DNA is significantly increased when the Mg^2+ ion is ***, an obvious change in the structure of the DNA is *** the DNA base groove and base pair parameters are *** find that, due to the introduction of the Mg2+ ion, the DNA base major groove becomes narrower.A potential mechanism for this observation is *** is confirmed that the Mg^2+ ion can enhance the stability of the DNA–protein complex.

关键词： cAMP response element binding protein(CREB) molecular dynamics(MD) simulation hydrogen bond Mg2+ ion

Acylfluorination of enynes via phosphine and silver catalysis

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Chinese Chemical Letters 2024年第8期35卷 260-264页

作者： Yu mao yilin Liu Xiaochen Wang Shengyang Ni yi Pan yi Wang State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

This work describes intermolecular acylfluorination of gem-difluoroenynes using acyl fluorides as both acyl source and fluorine ***-substituted allenones or furans could be selectively achieved via phosphine and silve... 详细信息

关键词： Phosphine catalysis Silver catalysis Difunctionalization Allenone Furan Trifluoromethyl

DMRG Studies on Properties of Undoped and Doped Molecule-Based Ferromagnetic Chain

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Communications in Theoretical Physics 2005年第6X期44卷 1099-1102页

作者： YAO Kai-Lun QIN yi LIU Qing-Mei LIU zu-Li Department of Physics and State Key Laboratory of Laser Technology Huazhong University of Science and Technology Wuhan 430074 China International Center of Materials Physics the Chinese Academy of Sciences Shengyang 110015 China

By using density matrix renormalization group （DMRG） method a model for organic molecule-based ferromagnetic chain is proposed. It is found that the ground states of Undoped and doped systems both exhibit ferrimagnetic ordering. The e-e repulsion plays an important role in the stability of the ferromagnetic state either in doped system or undoped system. For the undoped system, each unit cell coatains half of the total spins, which is consistent with Lieb＇s theorem. It is convinced that when the system is doped with one electron, a charge density wave is excited, which decreases the amplitude of spin density wave,therefore acting against the stability of ferromagnetic state.

关键词： DMRG antiferromagnetic exchange SDW spin density undoped doped