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Chinese Journal of Structural Chemistry 2007年第3期26卷 309-313页

作者： CHEN hua-Mei lin Hai lin hua-Kuan Department of Chemistry Nankai University Tianjin 300071 China State Key Laboratory of Functional Polymer Materials for Absorption and Separation Nankai University Tianjin 300071 China

The title compound, 1-（N,N-di-（p-toluenesulfonyl））-amino-2-（N＇-p-toluenesulfonyl）- amino-3,5-dinitrobenzene, was synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in orthorhombic, space group Pna21 with a = 13.723（2）, b = 25.354（4）, c = 8.6565（12） A, V= 3011.9（8） A^3, Z = 4, Mr = 660.68, F（000） = 1368, Dc = 1.457 g/cm^3, μ = 0.309, the final R = 0.0609 and wR = 0.1042. The H atom of N2-H group, which is the unique recognition site to anion, is enveloped by two oxygen atoms and one benzene from two and one p-toluenesulfonyl moieties, respectively.

关键词： sulfonylamide anion recognition receptor crystal structure

Mechanism of Residual Stress Reduction in Low Alloy Steel by a Low Frequency Alternating Magnetic Treatment

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Journal of Materials Science & Technology 2012年第9期28卷 803-808页

作者： Yanli Song lin hua School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

Residual stress reduction in low alloy steel by a low frequency alternating magnetic treatment and its mechanism were investigated. Experimental results revealed that average stress reductions of 20%-24% were obtained in the welded samples. Moreover, compared with the zones with lower initial stress levels, more remarkable stress reductions were obtained in the stress concentration zones. The microstructures and magnetic domains were observed by scanning electron microscopy （SEM） and atomic force microscopy （AFM）. Based on the analysis of the microstructure and magnetic domain changes, the mechanism of stress reduction by the magnetic treatment has been concluded：（1） the magneto-plastic deformations mainly due to the more uniform redistribution of dislocations are the fundamental cause of stress relaxation; and （2） surface topography is also proved to affect the magnetic treatment results to some degree by influencing magnetic domains.

关键词： Magnetic treatment Residual stress reduction Magneto-plastic deformations Surface topography

Preparation and Tribological Properties of Ni-P Electroless Composite Coating Containing Potassium Titanate Whisker

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Journal of Materials Science & Technology 2007年第3期23卷 387-391页

作者： Yaxu JIN lin hua School of Materials Science and Engineering Wuhan University of Technology Wuhan 430070 China

Nickel-phosphorus （Ni-P） composite coatings containing potassium titanate （K2Ti6O13） whiskers （PTWs） were prepared by electroless plating. The surface morphology and component of coatings were investigated by scanning electron microscopy （SEM） and energy dispersive X-ray spectroscopy （EDX）, respectively before and after wear test. The tribological performance was evaluated using a pin-on-disk wear tester under dry conditions. It is found that the Ni-P-PTWs composite coatings exhibit higher wear resistance than Ni-P and Ni-P-SiC electroless coatings. The favorable effects of PTWs on the tribological properties of the composite coatings are attributed to the super-strong mechanical properties and the specific tunneling structures of PTWs. The PTWs greatly reinforce the structure of the Ni-P-based composite coatings and thereby greatly reduce the adhesive and plough wear of Ni-P-PTWs composite coatings.

关键词： Potassium titanate whiskers Electroless plating Composite coating Tribological properties

Numerical simulation of dynamic large deformation and fracture damage for solid armature in electromagnetic railgun

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Defence Technology（防务技术） 2020年第2期16卷 348-353页

作者： Qing-hua lin Bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyP.O.Box210094NanjingPR China

The design of solid armature of railgun should take full account of its operating conditions and material properties because the armature is subjected to dynamic loading conditions and experiences a complicated electrical,thermal and mechanical process in the interior ballistic *** this paper present,we first introduced a multi-physical field model of railgun,followed by several examples to investigate the launching ***,we used the explicit finite element method,in which material nonlinearity and geometric nonlinearity were accounted,to investigate the deform behaviors of solid *** results show that the dynamic mechanical process of armature is dependent on the armature geometry,material and exciting electric *** the numerical simulation,the understanding of the fracture mechanism of solid armature was deepened.

关键词： Electromagnetic railgun Solid armature Fracture Explicit finite element Numerical simulation

UPPER BOUND METHOD FOR SINTERED POWDER MATERIALS IN PLANE STRAIN

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中国有色金属学会会刊：英文版 1994年第2期4卷 86-91页

作者： hua, lin Zhao, Zhongzhi Wuhan Inst of Technology Wuhan China

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关键词： sintered powder material upper bound method plane strain

Synthesis,Structure,and Property of a Three-dimensional Channel Quaternary Compound:Cs_(0.75(6))Er_(4.43(5))In_(3.32(6))S_(12)

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Chinese Journal of Structural Chemistry 2013年第12期32卷 1873-1879页

作者： WANG Peng lin hua Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences University of Chinese Academy of Sciences

A new quaternary rare-earth sulfide, Cs0.75（6）Er443（5）In3.32（6）S12 （1）, is discovered by high temperature solid state reactions with a slight excess of CsCI flux. The structure is characterized by single-crystal X-ray diffraction data, while crystallizes in hexagonal space group P63/m （No. 176） with a = 12.0329（6）, c = 3.8693（5）A, V= 485.18（7） A3, Z = 1, Mr = 1606.57, Dc = 5.499 g/cm3,μ = 25.457 mm-1, F（000） = 752, the final R = 0.0337 and wR = 0.0904 for 328 observed reflections with I 〉 2σ（I）. Its structure features a three-dimensional framework with hexagonal channels that are centered by Cs cations. Such channels are formed by double chains of edge-sharing M（1）S6 （M（1） = Er（1）/In（1）） octahedra and single chains of Er（2）S6 triprism interconnected by corner-sharing. The syntheses, single-crystal analyses, optical band gap and magnetic property are reported.

关键词： high temperature solid state crystal structure,magnetic property optical band gap

NUMERICAL SIMULATION FOR SHALLOW FLOW AND POLLUTANT DISPERSION BASED ON QUAD-TREE MESHES

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Journal of Hydrodynamics 2006年第2期18卷 161-169页

作者： LIU Xiao-dong hua Zu-lin State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow LakesCollege of Environmental Science and Engineering Hohai UniversityNanjing 210098 China

A 2D depth-averaged flow-pollutant coupled model based on quad-tree meshes was established to accurately simulate flows in water areas with irregular natural boundaries in this paper. The grids were generated by recursive subdivision about seeding points. A new neighbor-finding algorithm was presented. The governing equations were discrctized in collocated conservative variables by using the finite volume method, and the normal flux of mass, momentum and pollutants across the interlace between cells were computed by a Godunov-type Flux Difference Splitting （FDS） scheme. The model was applied to simulate flow fields around a groin. The computed values are in agreement with observed data. The results indicate that quad-tree meshes have fine local resolution, high efficiency and easy local refinement. It is clear that the quad-tree grid model can offer gains in efficiency when applied to complex flow domains or strong shear flows. Finally the model is applied to flow fields and concentration fields simulation in Jiangsu Haizhou Bay. The simulated polluted area is matched well with observations. Therefore, this model can be used to predict flow and concentration fields of actual water area with irregular natural land boundaries.

关键词： quad-tree grid shallow flow numerical simulation dispersion Godunov-type

Synthesis and Crystal Structure of N-(1′-H-Pyrrol-2′-ylcarbonyl)-5-amino-1,10-phenanthroline

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Chinese Journal of Structural Chemistry 2008年第2期27卷 163-166页

作者： WANG Yue-Hong lin Hai lin hua-Kuan Department of Chemistry Nankai University Tianjin 300071 China Key Laboratory of Functional Polymer Materials of the Ministry of Education Nankai University Tianjin 300071 China

The title compound, N-（1′-H-pyrrol-2′-ylcarbonyl）-5-amino-1,10-phenanthroline, was synthesized by the reaction of a-pyrrolyl carbonyl chloride and 5-amino-1,10-phenanthroline in pyridine. Determined by X-ray structure analysis, it crystallizes in triclinic system, space group P1 with the following crystallographic data： C20H21N5O3, Mr = 379.42, a = 7.8559（4）, b = 9.1681（6）, c = 14.6818（9） A, α= 73.254（10）,β= 88.938（15）, γ= 68.080（10）°, V= 934.66（10） A3, Z = 2, F（000） = 400, Dc = 1.348 g/cm^3 and p = 0.094 mm-1. The final R = 0.0680 and wR = 0.1419 for 2142 observed reflections with I 〉 2σ（/）, and R = 0.1084 and wR = 0.1643 for all reflections. Two aromatic ring planes （pyrrole and phenanthroline rings） are connected by the amide plane. Two different types of intermolecular hydrogen bonds, O-H…N and N-H…O, exist in the crystal. The title complex molecules are connected through hydrogen bonds and weak π-π stacking interactions to generate a 3-D supramolecule.

关键词： 1,10-phenanthroline pyrrole amide crystal structure

Ferroelectricity survives in the sub-nanometer scale

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Science China Materials 2023年第5期66卷 2105-2106页

作者： Yiqian Liu Yuan-hua lin State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Ultrathin materials with maintained functionalities are the prerequisites for the device miniaturization and *** materials are key ingredients in nonvolatile memories as information storage media and in field-effect transistors as gate dielectrics[1],and therefore their thickness scaling enables the high-capacity and energy-efficient ***,the longstanding problem for ultrathin ferroelectrics is that the strong depolarizing field can cancel ferroelectricity[2].In traditional barium titanates,the ultrathin film turns paraelectric without spontaneous polarizations[2,3].Moreover,realizing switchable ferroelectric behaviors is even more challenging because of the unsuppressed leakage *** recent years,although some studies have demonstrated that ferroelectricity can be stabilized in several nanometers in perovskites and fluorites[4-6],there still lacks direct evidence to confirm that ultrathin ferroelectrics have macroscopic hysteresis loops and polarization switching,which is the foundation of the practical usage of ultrathin ferroelectrics.

关键词： polarization ferroelectric maintained

The FENE Dumbbell Model near Equilibrium

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Acta Mathematica Sinica,English Series 2008年第4期24卷 529-538页

作者： Fang hua lin Ping ZHANG Courant Institute New York University New York NY 10012 USA Academy of Mathematics & Systems Science CAS Beijing 100080 P. R. China

We study the global existence of smooth solutions near the equilibrium to a coupled microscopic-macroscopic FENE dumbbell model which arises from the kinetic theory of diluted solutions of polymeric liquids with nonin... 详细信息

关键词： FENE dumbbell model polymeric liquids Navier-Stokes equations Fokker-Planck equations