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Synthesis and Crystal Structure of N-[4-(4-Methyl-phenylsulfamoyl)-phenyl]- 4-methyl-1,2,3-thiadiazole-5-carboxamide

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Chinese Journal of Structural Chemistry 2007年第5期26卷 501-504页

作者： WANG Jian-Guo XIAO yong-jun li Zheng-Ming SONG Hai-Bin （Elemento-organic Chemistry hlstitute State Key Laboratory ofElemento-organic Chemistry Nankai University Tianjin 300071 China

The crystal structure of the title compound （C17H16N4O3S2, Mr = 388.46） has been determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 13.688（2）, b = 16.704（3）, c = 8.3308（12）A, β = 99.474（6）°, V = 1878.8（5） A^3, Mr = 388.46, Z = 4, Dc = 1.373 g/cm3, μ = 0.308 mm^–1, F（000） = 808, R = 0.0389 and wR = 0.0917. X-ray analysis reveals that the crystal structure involves intermolecular N–H…O and N–H…N hydrogen bonds, which link the molecules into a layer parallel to the ac plane.

关键词： X-ray diffraction crystal structure synthesis

Entropy of Field Interacting With Two Atoms in Bell State

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Communications in Theoretical Physics 2009年第1期51卷 53-56页

作者： JIAO Zhi-yong MA jun-Mao li Ning FU Xia College of Physics Science and Technology China University of Petroleum （East China） Dongying 257061 China

In this paper, we investigate entropy properties of the single-mode coherent optical field interacting with the two two-level atoms initially in one of the four Bell states. It is found that the different initial states of the two atoms lead to different evolutions of field entropy and the intensity of the field plays an important role for the evolution properties of field entropy.

关键词： entropy optical field two-level atom Bell state entanglement

Preparation of Spherical Microfine Silicon Powder

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Journal of Wuhan University of Technology(Materials Science) 2008年第4期23卷 440-442页

作者： SHENG yong ZOU jun li Bing TU Mingjing College of Material Science and Engineering Sichuan University Chengdu 610065 China

Under certain conditions of proper temperature and pH value, sodium silicate was hydrolyzed in liquid ammonia chloride, and spherical microfine SiO2 powder in micrometer-size was prepared. In this experiment, the relationship between needed time and proper pH value, temperature, density of the solution, and its current capacity were found .The optimum conditions are pH 8.5, 70 ~C, and the concentration of sodium silicate is 0.6 mol/L for the density of the solution. The structure of spherical microfine silicon was characterized by SEM and XRD.

关键词： SiO2 powder spherical-structure

Homogenization heat treatment of Mg-7.0 wt%Y-1.0 wt%Nd-0.5 wt%Zr alloy

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Rare Metals 2020年第10期39卷 1196-1201页

作者： Jing-Bao liu Kui Zhang Jing-Tao Han Xing-Gang li yong-jun li Ming-Long Ma Jia-Wei Yuan Meng li State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous MetalsBeijing 100088 China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

The microstructures and mechanical properties of Mg-7.0 wt%Y-1.0 wt%Nd-0.5 wt%Zr magnesium alloy were investigated both in as-cast condition and after homogenization heat treatment by differential scanning calorimetry(DSC),optical microscopy(OM),X-ray diffraction(XRD),scanning electron microscopy(SEM)and hardness *** results indicate that the ascast alloy consists ofα-Mg matrix,Mg24 Y5 and Mg41 Nd5 phases,which are eutectic phases(cubic Y-rich phase).With the increase in homogenization temperature and time,the Mg24 Y5 and Mg41 Nd5 phases are completely dissolved into matrix,and only yttrium of intermetallic compounds leaves around *** homogenization heat treatment,the elements distributed uniformly and the grains grow up not obviously,only yttrium element of intermetallic compounds left around *** optimum homogenization condition is at 537℃for 16 *** mechanical properties are improved after homogenization,with tensile strength ofσb=181 MPa,yielding strength ofσ(0.2)=144 MPa and elongation ofδ=5.5%,which are better than those of as-cast alloy.

关键词： Rare earth magnesium alloy Homogenization Microstructure Hardness

Flow Uniformity of Roller-Type Quenching Machine

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Journal of Iron and Steel Research International 2010年第7期17卷 24-27页

作者： ZHU Dong-mei liU Guo-yong ZHANG Shao-jun li Mou-wei School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China

Three-dimensional finite element flow field model of spraying pipe of roller-type quenching machine is *** flow field with different structural parameters is *** grouping the nozzles,the spraying uniformity is analyzed under the conditions of different water inlet pipe diameter,different water inlet pipe distance,nozzle diameter and nozzle *** the spraying intensity absolute deviation and relative deviation are computed under different *** effect of different structural parameters on cooling uniformity is *** results provide theoretical basis for improving production quality and optimizing cooling device design.

关键词： roller-type quenching machine uniform cooling structural parameter

Recovery and in-situ reduction of precious metals by graphdiyne and graphdiyne oxide for antibacterial use

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Rare Metals 2024年第4期43卷 1747-1757页

作者： Ming-Ji Jiang Ya-Na Zhang ling-Shen Meng Jing Kang yong-jun li Alideertu Dong College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot010021China Engineering Research Center of Dairy Quality and Safety Control Technology Ministry of EducationInner Mongolia UniversityHohhot010021China Department of Chemistry University of ZurichCH-8057ZurichSwitzerland Laboratory of Organic Solids and Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing100190China

Based on the in-situ self-reduction and chemical stability,graphdiyne(GDY)and graphdiyne oxide(GDYO)are used as trapping agents to investigate the ability for recovering Au^(3+),Ag^+,and Pd^(2+)under different pH values and interfering *** strong acidity at pH=1,these two agents demonstrate high select recovery towards the three precious metal ions,which could be insitu reduced to nanoparticles(NPs).In addition,superparamagnetic Fe_(3)O_(4)NPs are deposited on the surfaces of GDY and *** magnetic responses enable GDYFe_(3)O_(4)to recover precious metals conveniently and efficiently by the aid of an external magnetic *** study also confirms the antibacterial activity of the as-recovered NPs deposited on GDY and GDYO against Escherichia coli and Staphylococcus aureus(1×10^(5)colony-forming unit(CFU)·mL^(-1)),and the antibacterial rates are 100%.This strategy of recovering precious metals and subsequently reusing to combat pathogens will be of great significance for environmental remediation and biomedical applications.

关键词： Graphdiyne In-situ reduction Recovery Precious metals Antibacterial

Microstructure and phase transformation of as-cast and annealed Mg–4Zn–1Y alloy containing quasi-crystal phase

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Rare Metals 2015年第4期34卷 239-244页

作者： Yang Yang Kui Zhang Xing-Gang li yong-jun li Ming-Long Ma Guo-liang Shi Jia-Wei Yuan State Key Laboratory for Fabrication and Processing of Nonferrous Metals General Research Institute for Nonferrous Metals

By means of optical microscope （OM）, X-ray diffraction （XRD）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM） analyses, the microstructures of as-cast and heat-treated Mg--4Zn-IY （wt%） alloy containing quasi-crystal phase were studied. The microstructure of the as-cast alloy consists of a-Mg solid solution grains, intermetallic particles and eutectic phases （W-phase and 1-phase）, and huge grains with seri- ous dendritic segregation are clearly observed. After heat treatment, phase transformation and dissolution occur in the alloy and many phases remain. When the alloy was treated above 410 ~C, the eutectic phases transform into spherical shape as the I-phase turns to W-phase. After heat treatment for long time, the alloy is over burnt and the W-phase decomposes to Mg-Y binary phase.

关键词： Mg-Zn-Y alloy Heat treatment Microstructure Phase transformation Icosahedral quasi-crystal

Vacuum joints of dispersion-strengthened copper and its applications in synchrotron radiation front end

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Nuclear Science and Techniques 2016年第6期27卷 74-78页

作者： yong-jun li Song Xue Min Zhang Dan-Dan Jia Dong-Bai Dou Yu Gao Shanghai Institute of Applied Physics Chinese Academy ofSciencesZhangJiangShanghai 201204China University of Chinese Academy of Sciences Beijing 100049China SKY Technology Development Co. LtdChinese Academyof SciencesShenyang 110179China

Masks are critical elements of synchrotron radiation front end that are exposed to high temperature and *** absorber material is typically comprised of dispersion-strengthened copper,which can retain high performance at elevated *** processes under vacuum,including brazing and electron beam welding,are novel approaches for prolonging the absorber and for reducing power *** mechanical properties of brazed joints and electron beam welded joints of dispersion-strengthened copper workpieces are evaluated by tensile testing at 20,100,and 200 *** testing results indicate that the tensile strength and elongation of both vacuum joints decrease with increasing *** to brazed joints,electron beam welded joints have higher tensile strength,better ductility,and more stable performance.A novel welded mask with a total length of 600 mm is presented and shown to be practical for use in the highest heat load front end in the Shanghai synchrotron radiation facility phase-Ⅱ beamline project.

关键词：上海同步辐射装置弥散强化铜焊接接头前端真空电子束焊接应用钎焊接头

Dislocation configuration evolution during extension twinning and its influence on precipitation behavior in AZ80 wrought magnesium alloy

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Journal of Magnesium and Alloys 2023年第7期11卷 2442-2457页

作者： Guo-liang Shi Kui Zhang Xing-Gang li yong-jun li Ming-Long Ma Jia-Wei Yuan Hong-Ju Zhang State Key Laboratory of Nonferrous Metals and Process Grinm Group Corporation Limited(GRINM)Beijing 100088China GRIMAT Engineering Institute Co. Ltd.Beijing 101407China Guobiao(Beijing)Testing and Certification.Co. Ltd.Beijing 101407China

Thermomechanical treatment T10(extension twinning+aging treatment)can largely enhance the precipitation strengthening effect of magnesium *** this study,dislocation structure evolution and precipitation behavior during T10 treatment of an AZ80 extruded bar were analyzed mainly by two-beam diffraction in *** a compressive strain of 1%in the extrusion direction(ED),a typical dislocation configuration,including basal I1 stacking faults(SFs)anddislocations,has been established in extension *** the strain reaches 7%,the volume fraction of extension twins increases to more than 90%at which point high dense I1 SFs anddislocations *** aging for 2 h at 150℃for the 7%strained sample,masses of basal I1 SFs anddislocations remain in the extension twins and can act as effective nucleation sites and solute fast-diffusion channels for continuous ***,the precipitates in extension twins become highly dense.

关键词： Magnesium alloy Extension twin Dislocation Stacking fault Precipitation