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Interface profile evolution between binary immiscible fluids induced by high magnetic field gradients

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Science China(Physics,Mechanics & Astronomy) 2010年第7期53卷 1319-1324页

作者： ZHAO LiJia YOU Yue TIAN YongHua YANG HongKai WANG Qiang HE JiCheng Key Laboratory of Electromagnetic Processing of materials(Ministry of Education) Northeastern UniversityShenyang 110004China

A mechanical analysis is done to find the evolution of the interface profile between binary immiscible fluids induced by a three-dimensional orthogonal magnetic field *** the experiments,the changes of the interface profile between four groups of binary immiscible fluids are investigated under the same horizontal magnetic field *** binary immiscible fluids are made of benzene and other liquids,like CuSO4,Fecl3,FeSO4 or Cucl2 aqueous *** addition,the interface profile between the benzene and CuSO4 aqueous solution is examined under different horizontal magnetic field *** experimental results are consistent with the theoretical *** study explains the enhanced Moses effect from a mechanics ***,a new method for susceptibility measurement is proposed based on this enhanced Moses effect.

关键词： high magnetic fields binary immiscible fluids interface enhanced Moses effect magneto hydrodynamics

Fabrication of Z-type barium ferrite/silica composites with enhanced microwave absorption

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Science China(Technological Sciences) 2014年第9期57卷 1858-1864页

作者： SHEN JunHai CHEN KeYu LI LiangChao DING Yan LI JuanBi KONG WeiQiu Key Laboratory of the Ministry of Education for Advanced Catalysis materials Department of Chemistry Zhejiang Normal University

The Z-type barium ferrite/silica composites(Z-BCF/SiO2)were fabricated by in situ chemical synthesis *** composition,structure,morphology and magnetic behavior of the composites were characterized by chemical analysis,IR,XRD,SEM,TEM and *** results indicated that there were some interactions between two components in the Z-BCF/SiO2 composites due to the coating of SiO2 on the Z-BCF *** magnetic properties of the Z-BCF/SiO2 composites were evidently less than that of the Z-BCF,owing to the small volume fraction of magnetic components in the *** to the good transmission and loss properties on electromagnetic waves,the composites were better at microwave absorption than the parent ***,this research laid a foundation for the fabrication of highly efficient microwave absorbing material with enhanced wave impedance matching.

关键词：微波吸收材料二氧化硅复合材料钡铁氧体制造 Z型化学合成法 X射线衍射

Synthesis,Crystal Structure and Properties of a Novel Coordination Polymer Based on a Trinuclear Mn(Ⅱ) Cluster:[Mn_3(bpta)_2(bip)_2]_n

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Chinese Journal of Structural Chemistry 2013年第11期32卷 1633-1638页

作者：王淑菊田彦文由立新丁茯孙亚光 School of materials and Metallurgy Northeastern University Laboratory of Coordination Chemistry Shenyang University of Chemical Technology

The coordination polymer, [Mn3（bpta）2（bip）2], （H3bpta = biphenyl-3,3＇,5-tricar- boxylic acid, bip = 2,6-bis（imidazole-1-yl）pyridine）, has been synthesized under hydrothermal con- ditions and characterized by elemental analysis, FT-IR, XRD, TGA and single-crystal X-ray diffraction. It crystallizes in monoclinic, space group P21/c with a = 14.919（3）, b = 9.780（2）, c = 20.352（7） A, V = 2344.4（10） A3, Z= 2, C52H32Mn3N10012, Mr = 1153.70, Dc = 1.634 g/cm3, p（MoKa） = 0.876 mm-1, F（000） = 1170, the finalR = 0.0605 and wR = 0.1177. The complex forms a 2D layer with trinuclear Mn（II） units and further assembles into a 3D supramolecular network structure through C-H..＇O hydrogen bonding and C-H...π interactions. Moreover, the negative J value indicates the presence of antiferromagnetic coupling between the Mn（II） ions within a trinuclear unit.

关键词： coordination polymer crystal structure trinuclear Mn(ll) cluster biphenyl-3,3",5-tricarboxylic acid 2,6-bis(imidazole-l-yl)pyridine

Preparation and antimicrobial ability of natural porous antibacterial materials

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Journal of Central South University of Technology 2005年第4期12卷 370-375页

作者：董发勤李国武孙志刚沈刚冯启明代群威 School of materials Science and Engineering Southwest University of Science and Technology Mianyang 621010 China School

The liquid ion exchange method, solid salt melt method and dry-wet circulation method were used to prepare natural porous antimicrobial materials with natural minerals, such as zeolite, spilite, palygorskite and montmorillonite, respectively. Atomic absorption spectrum and X-ray diffraction analysis were carried out to investigate the effects of Ag+, Cu 2+ and Zn 2+ on antimicrobial abilities of natural porous minerals, and the effect of preparation method on ion exchange capacity of antimicrobial material, respectively. The results show that for the ion exchange capacity, clay mineral is higher than fibrous mineral, i.e. both zeolite and montmorillonite are higher; the antimicrobial ability of material with Ag+ is the best; the exchange capacities of materials with Cu 2+ or Zn 2+ are all higher, but the antimicrobial ability of Cu 2+ is better than that of Zn 2+ .

关键词：熔盐离子交换法抗菌沸石交换容量佛石杀菌性原子吸收分光光度法

Electrical conductivity of the graphene nanoplatelets coated natural and synthetic fibres using electrophoretic deposition technique

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International Journal of Smart and Nano materials 2018年第3期9卷 167-183,I0002页

作者： Hamid Souri Debes Bhattacharyya Centre for Advanced Composite materials Department of Mechanical EngineeringThe University of AucklandAucklandNew Zealand

Herein,electrically conductive natural and synthetic yarns through electrophoretic deposition(EPD)technique were fabricated.A parametric study on the conductivity enhancement of the yarns is carried out by Taguchi *** this method,the desirable conditions are determined by studying the effects of important parameters on the electrical conductivity of the yarns in the EPD coating *** on the L18 design of experiments table,the preferred combination of factors to obtain the highest electrical conductivity of the yarns is found by Taguchi *** addition,the Pareto ANOVA analysis is conducted to identify the major contributing factors on the electrical conductivity of the *** techniques,such as scanning electron microscopy(SEM),Fourier transformed infrared spectroscopy(FTIR)in attenuated total reflectance(ATR)mode,and thermogravimetric analysis(TGA)are utilised for better understanding the microstructure and physical *** powered by only 3 V,the maximum temperature of a Joule heated conductive sample based on natural fibre yarns reached 102°C in less than 25 s.

关键词： Graphene nanoplatelets electrical conductivity natural fibres electrothermal behaviour Taguchi method

Microstructure refinement and magnetic properties enhancement of nanocrystalline Nd_(12.3)Fe_(81.7)B_(6.0) ribbons by addition of Zr

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Science China(Technological Sciences) 2009年第7期52卷 1891-1896页

作者： BAO XiaoQian, QIAO Yi, GAO XueXu, ZHU Jie & ZHOU ShouZeng State Key Laboratory for Advanced Metals and materials, University of Science and Technology Beijing, Beijing 100083, China State Key Laboratory for Advanced Metals and materials University of Science and Technology Beijing Beijing China

Effects of Zr addition and annealing treatment on the formation, microstructure and magnetic properties of Nd12.3Fe81.7?xZrxB6.0 (x=0―3.0) ribbons melt-spun and annealed have been systematically investigated by means of vibrating sample magnetometer (VSM), differential scanning calorimeter (DSC), X-ray diffraction (XRD), and high resolution scanning electron microscopy (HRSEM). Phase analysis reveals that Nd2Fe14B is single-phase material. It has been found that the intrinsic coercivity Hci of the optimally processed Nd12.3Fe81.7?xZrxB6.0 ribbons increases monotonically from 751.7 kA/m for x=0 to 1005.3 kA/m for x=3.0. The remanence polarization Jr and maximum energy product (BH)max increase first with Zr addition, then slightly decrease with further increasing Zr content. Optimum magnetic properties with Jr=1.041 T, Hci=887.5 kA/m and (BH)max=175.2 kJ/m3 have been achieved for the ribbons with x=1.5. The significant improvement of magnetic properties originates from the finer grains of the ribbons by introducing Zr.

关键词： Nd-Fe-B magnets nanocrystalline microstructure magnetic properties

Complex Impedance Spectra analysis of SnO_2-glaze Composites

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Journal of Wuhan University of Technology(materials Science) 2006年第4期21卷 121-125页

作者：颜东亮吴建青 College of materials Science and Engineering South China University of Technology Guangzhou 510640 China

SnO2-glaze composites were prepared by Sb-doped SnO2 and SiO2-CaO-Al2O3-B2O3 glaze. The composites changed from an electrical insulator to a conductor as the SnO2 content increased from Owt% to 90 wt% . The complex impedance spectra of the fabricated composites were investigated in the frequency range of 100Hz-40 MHz and three kinds of typical shape of complex impedance spectra were recorded and analyzed. The ,spectrum is quite close to the model of conduction via nonohmic contactiug when the SnO2 content is relatively low, In high loading region, the spectrum shows the conduction pattern through ohmic contact chains . In the moderate loading region, the model is a mixture of the above two models. Equivalent circuit of the composite changes from resistor-capacitor circuit to resistor-inductor circuit as the content of SnO2 increases.

关键词： SnO2-glaze composites impedance spectra conduction model

Columnar to Equiaxed Transition During Solidification of Small Ingot by Using Electric Current Pulse

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Journal of Iron and Steel Research(International) 2009年第6期16卷 7-12页

作者： LI Jie MA Jian-hong SONG Chang-jiang LI Zhi-jun GAO Yu-lai ZHAI Qi-jie Shanghai Key Laboratory of Modern Metallurgy and materials Processing Shanghai University Shanghai 200072 China

A new approach to applying the electric current pulse （ECP） with parallel electrodes to the promotion of the transition from columnar crystal to equiaxed crystal and the improvement of macrosegregation was introduced. The ECP was applied to different stages of the solidification. The results showed that the application of the ECP in both the initial stage （the thickness of solidified shell reached 2 mm approximately） and the late stage （the thickness of solidified shell reached 14 mm approximately） of solidification can promote the columnar to equiaxed transition （CET）. The analysis showed that during solidification, a large number of nuclei around the upper surface fell off due to ECP, which subsequently showered on the melt and impinged the growth front of the columnar crystal. Therefore, the CEToccurred. In addition, this method was also employed to influence the solidification process of bearing steel, and the results showed that the structure was changed from columnar crystal to equiaxed crystal, indicating that ECP can enhance the homogeneity of structure and composition of bearing steel.

关键词： columnar to equiaxed transition solidification electric current pulse macrosegregation

Thermal-Fluid-Structure Coupling analysis of Flexible Corrugated Cryogenic Hose

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China Ocean Engineering 2022年第4期36卷 658-665页

作者： YANG Liang LIU Miao-er LIU Yun LI Fang-qiu FAN Jia-kun LIU Fu-peng LU Zhao-kuan YANG Jian-ye YAN Jun CNOOC Gas&Power Group Co. Ltd.Beijing 100028China CNOOC Research Institute Co. Ltd.Beijing 100028China Offshore Oil Engineering Co. Ltd.Tianjin 300461China Ningbo Institute of Dalian University of Technology Ningbo 315016China State Key Laboratory of Structural analysis for Industrial Equipment Department of Engineering MechanicsInter-national Research Center for Computational MechanicsDalian University of TechnologyDalian 116024China

This work presents a numerical investigation of the thermal–fluid–structure coupling behavior of the liquid natural gas(LNG)transported in the flexible corrugated cryogenic hose.A three-dimensional model of the corrugated hose structure composed of multiple layers of different materials is established and coupled with turbulent LNG flow and heat transfer models in the commercial software ANSYS *** flow transport behavior,heat transfer across the hose layers,and structural response caused by the flow are *** studies are performed to evaluate the impacts of inlet flow rate and thermal conductivity of insulation material on the temperature and structural stress of the corrugated *** study found that,compared with a regular operating condition,higher inlet flow velocities not only suppress the heat gain of the LNG but also lower the flow-induced structural *** insulation layer exhibits excellent performance in maintaining the temperature at the fluid–structure interface,showing little temperature change with respect to material thermal conductivity and ambient *** simulation results may contribute to the research and design of the flexible corrugated cryogenic hoses and provide guidance for safer and more efficient field operations.

关键词： flexible corrugated cryogenic hose LNG computational fluid dynamics thermal–fluid–structure coupling