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Chinese Chemical Letters 2011年第7期22卷 847-850页

作者： en Ju wang Guang Ying Chen Hainan Provincial Key Laboratory of Tropical Pharmaceutical Herb Chemistry School of Chemistry & Chemical engineering Hainan Normal University Haikou 571158 China

The inclusion complex of β-cyclodextrin （β-CD） with 4-chlorobenzoic acid was synthesized and its crystal structure was determined by single crystal X-ray diffraction under cryogenic condition. The complex contains two β-CDs, two 4-chlorobenzoic acids and twenty-nine water molecules in the asymmetric unit, and can be formulated as 2（C42H70O35）·2（CTH5O2Cl）·29（H2O）. In the crystal lattice, two β-CDs form a face-to-face dimer jointed together through hydrogen bonding between the secondary hydroxyl groups of β--CDs. Two 4-chlorobenzoic acid molecules which contact by C-Cl…π interactions are included in the β-CD dimer cavity. The β-CD dimers are arranged in brickwork-like pattern along the crystallographic a-axis. The effect of guest molecule length on the inclusion geometry was discussed by comparative study of some fl-CD complexes containing similar guests.

关键词： β-Cyclodextrin 4-Chlorobenzoic acid Inclusion complex Crystal structure C-Cl…π interaction

Cementing properties of steel slag activated by sodium silicates and sodium hydroxide

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Journal of University of Science and Technology Beijing 2005年第5期12卷 464-468页

作者： Wen Ni en wang Jianping Li Han Sun Civil and environmental engineering School University of Science and Technology Beijing Beijing 100083 China

Steel slag which is mainly composed of γ-Ca2SiO4 and other silicates or alumino-silicates is activated by sodium sificates and sodium hydroxide. The powders of such steel slag are usually inert to hydrate and subsequently have very low ability of cementing. But when sodium silicates and sodium hydroxide are used as activators the steel slag shows very good properties of cementing. When activated with NaOH solution the hardened slurry of the steel slag has a compressive strength of 11.13 MPa after being cured for 28 days. When activated with Na2SiO3 solution the samples after being cured for 28 days have an average compres- sive strength of 40.23 MPa. While the steel slag slurry which is only mixed with water has a compressive of 0.88 MPa after being cured for 28 days.

关键词： steel slag sodium silicate sodium hydroxide cement binding material

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受载砂岩变形破坏过程磁场响应规律研究

岩土力学 2024年第6期45卷 1803-1812页

作者：殷山宋大钊王恩元何学秋李忠辉刘晓斐刘玉冰中国矿业大学安全工程学院江苏徐州221116 北京科技大学土木与资源工程学院北京100083 中国矿业大学煤岩动力灾害防控理论与技术国家矿山安全监察局重点实验室江苏徐州221116

探寻岩石破坏过程新的物理响应规律,将会推动岩体监测预警技术的发展。利用磁通门弱磁检测技术,开展了单轴加载和循环加卸载砂岩受载破坏磁场监测试验,测试了砂岩在变形破坏过程中的磁场信号,分析了磁场与载荷、声发射之间的关系。结果... 详细信息

探寻岩石破坏过程新的物理响应规律,将会推动岩体监测预警技术的发展。利用磁通门弱磁检测技术,开展了单轴加载和循环加卸载砂岩受载破坏磁场监测试验,测试了砂岩在变形破坏过程中的磁场信号,分析了磁场与载荷、声发射之间的关系。结果表明:砂岩在变形破坏过程中能够产生磁场信号,在单轴加载过程中,随着载荷增加,压密阶段磁场信号波动上升,波动系数较大;弹性阶段磁场信号稳定增大,波动系数变小;塑性阶段磁场信号显著增加,塑性阶段后期波动系数开始增大;破坏阶段磁场信号快速增加,波动系数变化较大,与试样载荷降和主破坏对应。相对于波动系数,磁场信号方差在前3个受载阶段较为稳定,破坏阶段的方差逐渐增大,并出现显著突变。在循环加卸载过程中,当载荷增加时磁场信号逐渐增大,载荷减小时磁场信号逐渐减小,试样临近失稳破坏时,磁场信号快速增加,显著高于前期循环加卸载过程。磁场信号与声发射计数具有较好的对应关系,表明磁场的产生与试样变形破坏密切相关。在岩体变形破坏过程中,矿物颗粒发生非均匀变形,界面处的电平衡被打破,自由电荷产生、迁移,引起电流变化,运动电荷或电流变化产生了磁场信号。利用磁场信号评估岩体的稳定性,有望成为一种无损、非接触、可连续监测的新方法。

关键词：砂岩变形破坏磁场信号循环加卸载监测预警

Effects of vertical electromagnetic stirring on grain refinement and macrosegregation control of bearing steel billet in continuous casting

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Journal of Iron and Steel Research International 2017年第5期24卷 483-489页

作者： Yu Xu en-gang wang Zhuang Li An-yuan Deng Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education) Northeastern University Shenyang 110819 Liaoning China School of Metallurgy Northeastern University Shenyang 110819 Liaoning China School of Materials Science and engineering Northeastern University Shenyang 110819 Liaoning China

The grain refinement and macrosegregation control of GCrl5 bearing steel were investigated under a type of rarely-used electromagnetic stirring, vertical electromagnetic stirring （V-EMS）, in continuous casting. V-EMS can create an upward electromagnetic force and generate longitudinal loop convection, which ena- bles the better mixing of the upper part with the lower part of the liquid steel. The results showed that ap- plying V-EMS can enlarge the region of the equiaxed grain, decrease the secondary dendrite arm spacing （SDAS） and reduce the segregation of both carbon and sulfur. After applying V-EMS, liquid steel with a high solute concentration is brought to the dendrite tips, making the dendrite arms partially melt. The length of the dendrite fragment is approximately 1.8 mm, 10 to 12 times the SDAS. Upon increasing the amount of cooling water from 2.0 to 3.5 m3/h, the dendrite fragments exhibit an obvious aggregation fol- lowing V-EMS. Finally, a criterion for dendrite fragmentation under V-EMS was derived based on the dendrite fragmentation theory of Campanella et al.

关键词： Vertical electromagnetic stirring Dendrite fragmentation Grain refinement Continuous casting Bearing steel Macrosegregation control

Synthesis of Coordination Polymers Using Different Maleic Acid Ligands under Hydrothermal Conditions

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Chemical Research in Chinese Universities 2007年第3期23卷 245-249页

作者： wang Xiao-lan wang en-bo XU Xin-xin Institute of Polyoxometalate Chemistry School of Chemistry Northeast Normal University Changchun 130024 P. R. China Department of Chemistry Baicheng Education Normal College Baicheng 137000 P. R. China

A novel coordination polymer, [ Ni （mal）（1,10＇-phen）（ H2O） ] n （ 1 ）（ mal = malate, 1,10＇-phen = 1,10- phenanthroline） was synthesized using malic acid which was generated from maleic acid via hydrothermal reaction. Complex 1, which displays a two-dimensional supramolecular network, was formed by the addition reaction of Ni and maleic acid with water molecules. To our knowledge, several coordination polymers have been directly synthesized from malic acid, but these types of complexes have seldom been synthesized from maleic acid via hydrothermal reactions. When Ni（ Ⅱ ） ion was changed to Zn（ Ⅱ） ion under the same condition, two-dimensional covalent complex 2 [ Zn2 （fma） 2 （1,10＇-phen） 2 ] n （fma = fumatic acid） was formed. Furthermore, complex 2 exhibits intense photolumi- nescent property at room temperature.

关键词： Maleic acid Hydrothermal reaction Mixed ligands Photoluminescent property

A new extended structural compound based on saturated Wells-Dawson polyoxoanions

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Chinese Chemical Letters 2009年第11期20卷 1381-1385页

作者： Min Xu Jia Liu en Bo wang Key Laboratory of Polyoxometalate Science of Ministry of Education Institute of Polyoxometalate Chemistry Department of Chemistry Northeast Normal University Changchun Jilin 130024 China Department of Chemistry Tonghua Normal University Tonghua Jilin 134002 China

A new 3D extended structural compound, （dpdo）2H2{[Cu（2,2＇-bipy）212（P2W18O62）}.SH2O 1 （dpdo = 4,4＇-bipyridine-N,N＇- dioxide; 2,2＇-bipy = 2,2＇-bipyridine）, has been hydrothermally synthesized and characterized by elemental analyses, IR, TG analyses, cyclic voltammetry, and single-crystal X-my diffraction. Compound 1 is built up of [P2WlsO62]6- cluster as the structural motif covalently linked by [Cu（2,2＇-bipy）2]^2＋ coordination complexes to yield the 1D chains, which axe further in close contact forming a 3D supramolecular framework via aromatic π-π stacking interactions and extensive hydrogen-bonding interactions among polyoxoanions, coordinated 2,2＇-bipy organic ligands, free dpdo organic molecules and lattice water molecules.

关键词： 3D extended structures Dawson-type polyoxometalates Copper-organic complexes

Isomerization and Antiacidolysis Properties of Molybdic Heteropoly Blues with Keggin Structure

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Chemical Research in Chinese Universities 1995年第2期11卷 98-104页

作者： wang Zuo-ping,XU Lin,SHen en-hong and wang en-bo (Department of Chemistry,Northeast Normal University,Changchun,130024) NE NORMAL UNIV DEPT CHEMCHANGCHUN 130024PEOPLES R CHINA

For eight kinds of acidic potassium salts of hetcropoly blues which have not been reported in literature,the isomeri/.ation reaction in solution for these two-and four-electron hcteropoly blue solids were investigated by means of polarograms,cyclic voltammetry,31P NMR and X-ray diffraction *** heteropolynier of PMo12 and AsMo12 converte to their β-isomers during isomerization reaction which were found to have antiacidolysis property.

关键词： Heteropoly blue Keggin structure Isomenzation

Effect of Structure Parameters on Power and Magnetic Field in Electromagnetic Soft-Contact Continuous Casting System

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Journal of Iron and Steel Research International 2008年第1期15卷 19-24页

作者： DenG An-yuan wang en-gang HE Ji-cheng Key Laboratory of National Education Ministry for Electromagnetic Processing of Materials Northeastern UniversityShenyang 110004 Liaoning China

To design a power source system and mold for electromagnetic soft-contact continuous casting process and to theoretically estimate the heat losses from the charges and the system power, the effect of structure parameters on system power and magnetic flux density distribution was calculated using finite element method. The results show that as for electromagnetic soft-contact continuous casting system with partial-segment type mold, the power consumption is much more than that with a full-segment type mold; about 62% of electric power is dissipated in the mold, and the effective acting range of magnetic field is relatively narrow. Optimizing mold structure is a crucial measure of remarkably reducing mold power consumption and saving electric energy. Increasing slit number, width, and length can remarkably increase the magnetic flux density in the mold and can reduce the electric energy consumption. Among structure parameters, slit number and slit width are relatively more effective to reduce energy consumption. For a round billet electromagnetic continuous casting system with diameter of 178 ram, the reasonable slit number, width, and length are about 24--32, 0. 5--1.0 mm, and 160 mm, respectively.

关键词： continuous casting soft-contact mold electromagnetic field electric power structure parameter

A New Molecular-Dynamics Approach for Fully Relaxed Crystals at Constant Pressure

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Chinese Physics Letters 1997年第10期14卷 764-767页

作者： LIU Gang wang en-ge wang Ding-sheng Laboratory for Surface Physics Institute of Physics&Certre for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080

A new molecular-dynamics method at constant pressure has been *** the three edge vectors of a crystal cell as well as the position vectors of all particles are taken as independent variables,this method allows the crystal to relax ***,the effect of pressure on the crystal structure is explicitly given in this *** an example,the evolution process of cobalt from a structure far from the final one to the ideal hexagonal close packing structure was given.

关键词： crystal structure vectors

Down-regulation of transforming growth factor β1/activin receptor-like kinase 1 pathway gene expression by herbal compound 861 is related to deactivation of LX-2 cells

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World Journal of Gastroenterology 2008年第18期14卷 2894-2899页

作者： Li Li Xin-Yan Zhao Bao-en wang Liver Research Center Beijing Friendship Hospital Capital Medical University Beijing 100050 China

AIM: To investigate the effect of herbal compound 861 (Cpd861) on the transforming growth factor-β1 (TGFβ1)/ activin receptor-like kinase 1 (ALK1, type Ⅰ receptor) signaling-pathway-related gene expression in the LX-2 cell line, and the inhibitory mechanism of Cpd861 on the activation of LX-2 cells. METHODS: LX-2 cells were treated with TGFβ1 (5 ng/mL) Cpd861 (0.1 mg/mL), TGFβ1 (5 ng/mL) plus Cpd861 (5 ng/mL) for 24 h to investigate the effect of Cpd861 on the TGFβ1/ALK1 pathway. Real-time PCR was performed to examine the expression of α-SMA (α-smooth muscle actin), ALK1, Id1 (inhibitor of differentiation 1). Western blotting was carried out to measure the levels of α-SMA and phosphorylated Smad1, and immunocytochemical analysis for the expression of α-SMA. RESULTS: In LX-2 cells, TGFβ1/ALK1-pathway-related gene expression could be stimulated by TGFβ1, which led to excessive activation of the cells. Cpd861 decreased the activation of LX-2 cells by reducing the expression of α-SMA mRNA and protein expression. This effect was related to inhibition of the above TGFβ1/ALK1-pathway- related expression of genes such as Id1 and ALK1, and phosphorylation of Smad1 in LX-2 cells, even with TGFβ1 co-treatment for 24 h. CONCLUSION: Cpd861 can restrain the activation of LX-2 cells by inhibiting the TGFβ1/ALK1/Smad1 pathway.

关键词： Herbal compound 861 LX-2 cell Activin receptor-like kinase 1 Inhibitor of differentiation 1 Smad1