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现象与过程可视化的“配合物的形成”系列实验研究

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化学教育(中英文) 2025年第3期46卷 97-101页

作者：罗敏杨蔡利杨丽君刘茜西华师范大学化学教育研究所四川南充637002

设计了以“滴”为计量单位、以微距摄影为观察方式的可视化微型化学实验。在表面皿中探究铜氨配合物、银氨配合物和铁离子配合物的形成过程,使反应空间平面化。通过智能手机和手机微距镜头的配合使用,可明晰配合物和沉淀的区别。利用投... 详细信息

设计了以“滴”为计量单位、以微距摄影为观察方式的可视化微型化学实验。在表面皿中探究铜氨配合物、银氨配合物和铁离子配合物的形成过程,使反应空间平面化。通过智能手机和手机微距镜头的配合使用,可明晰配合物和沉淀的区别。利用投影技术,可清晰地在课堂上呈现实验过程中沉淀的生成和溶解等微观现象。制备铜氨配合物时,晶体的析出更是美不可言。改进后的实验具有可视化、微型化、安全环保等特点。

关键词：配合物的形成可视化微距摄影微型实验

Numerical simulation of flow in swirl injector for power-law fluid

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航空动力学报 2012年第4期27卷 890-899页

作者： WANG Feng FU Qing-fei yang li-jun School of Astronautics Northwestern Polytechnical UniversityXi'an 710072China School of Astronautics Beijing University of Aeronautics and AstronauticsBeijing 100191China

In order to investigate the flow characteristics of swirl injectors for gelled propellants,which actually behaved as non-Newtonian power-law fluid,a swirl axisymmetric model was established to solve Navier-Stokes equations and VOF(volume of fluid) equation,and the power-law constitutive equation was used to describe the rheology characteristics of the gelled *** film thickness and velocity distribution in the swirl injector under different flow conditions were studied *** simulation results show that the increased geometry characteristic parameter of the swirl injector contributes to the decrease of liquid film *** liquid film thickness is almost independent of the pressure *** rheologic parameters have great influences on the inner flow of swirl injector: by increasing the fluid consistency index K and power index n,both the axial and the swirl velocities decrease dramatically;higher fluid consistency index K and power index n make the liquid film thickness *** the viscosity is large enough,the air core in the injector would vanish.

关键词： numerical simulation gelled propellants power-law fluid swirl injector inner flow

Effect of substrate materials on rutile crystalline orientation in plasma-sprayed TiO2 coatings

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 62-66页

作者： yang Guan-jun li Chang-jiu WANG Yu-yue State Key Laboratory for Mechanical Behavior of Materials Xi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of Materials Xi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of Materials Xi''an Jiaotong University Xi''an 710049 China

TiO2 coatings are of technical importance owing to their promising applications to photocatalytical, electrical, optical and tribological coatings. Thermal spraying process has been widely used to deposit both metallic and nonmetallic coatings. During thermal spraying, spray particle at fully or partially melted condition is projected to a substrate and subsequently flattens, rapidly cools and solidifies. Therefore, a coating in lamellar structure is usually formed as a quenched microstructure. TiO2 coatings were deposited on different substrates through plasma spraying with fused-crushed powder in rutile phase as feedstock to reveal the crystalline orientation in the coatings. XRD results show that the coatings consist of rutile phase with a fraction of anatase phase, and the rutile phase presents a preferable crystalline orientation along [101] direction. It is found that the orientation factors of rutile phase in the thin coatings are significantly influenced by substrate materials. The thick coatings yield the same orientation factors of 0.22 to 0.23 on all substrates in spite of substrate materials. It is considered that the thermal properties of substrate materials are the dominant factors for the preferable crystalline orientation in rutile phase within plasmasprayed TiO2 coating.

关键词： titanium oxide thermal spray coatings rutile orientation

Seismic Analysis of Shear-Wall Structures with Vertically Installed Dampers

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维普期刊数据库

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Journal of China University of Geosciences 2005年第4期16卷 349-353页

作者： yang jun li li Fan Aiwu School of Civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China

Shear-wall structures are quite common in seismic areas because of their successful seismic behavior during severe earthquakes. But shear walls are prone to brittle failure. This study proposes a new method of vertically installed dampers （VID） to reduce the vibration in shear-wall structures. The motion characteristic of a vertical damping system is that every mass has horizontal and rotational displacements simultaneously, The establishment of dynamic equations should take into account the equilibrium conditions of both horizontal and rotational vibrations. Dynamic equilibrium equations of VID systems are derived from a model of a structure with VID. An example shear-wall structure, with and with- out VID, is studied. There are some changes in the characteristics of the maximum horizontal displacement response. Without dampers, the relative displacements between different floors in the shear wall increase with height. With dampers, the relative displacements are more uniformly distributed, and lateral displacements at the top and at the bottom are closer. When the damping coefficient is 1 000 kN · s/ m, the numerical results reveal that the maximum horizontal displacement and the maximum rotational displacement of the top floor have reduced by 59.3 % and 54.8 % respectively.

关键词： shear wall damper dynamic equilibrium equation seismic response.

Distribution optimization of circulating water in air-cooled heat exchangers for a typical indirect dry cooling system on the basis of entransy dissipation

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Science China(Technological Sciences) 2015年第4期58卷 617-629页

作者： SUN Jian YUAN Kai yang li jun CHEN lin DU Xiao Ze yang Yong Ping Key Laboratory of Condition Monitoring and Control for Power Plant Equipments of Ministry of Education School of Energy Power and Mechanical Engineering North China Electric Power University

The flow and heat transfer of air-cooled heat exchangers play important roles in the performance of indirect dry cooling systems in power plants,so it is of benefit to the design and operation of a typical indirect dry cooling system to optimize the thermo-flow characteristics of air-cooled heat *** entransy dissipation method is applied to the performance optimization of air-cooled heat exchangers in this *** irreversible heat transfer processes in air-cooled heat exchangers,the heat transfer between circulating water and cooling air and the mixing of circulating water,are taken into account and analyzed by means of the entransy dissipation *** total entransy dissipation rate,which connects the geometrical parameters of air-cooled heat exchanger sectors and the heat capacity rates of the fluids to the heat flow rate in every sector,is *** on the mathematical relation and the conditional extremum method,an optimization equation group is derived,by which the air-cooled heat exchanger with known air-side parameters is optimized,showing that the entransy dissipation based optimization approach can contribute to the distribution optimization of circulating water in air-cooled heat exchangers of a typical indirect dry cooling system.

关键词： indirect dry cooling system air-cooled heat exchanger entransy dissipation optimization

NUMERICAL SIMULATION OF IRREGULAR WAVE-SIMULATING IRREGULAR WAVE TRAIN

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Journal of Hydrodynamics 2010年第4期22卷 537-545页

作者： liANG Xiu-feng yang Jian-min li jun XIAO Long-fei li Xin State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200030 China

In real sea states,damage incidents on offshore floating structures are not due to the whole time series of wave elevation characterized as statistical one but due to few extreme waves or wave groups in irregular wave ***,using CFD tools to precisely simulate predetermined irregular wave train will lay sound basis for understanding the local characteristic of the flow field and impact loads on offshore floating structures when damage incidents *** this article,the generation of single extreme wave is investigated in a numerical wave ***,experimental irregular wave train is decomposed into certain number of small-amplitude *** Fourier series expansion is performed to determine the amplitude and initial phase angle of each wave component.A hydrodynamic transfer function is used to calculate the amplitude of wave-maker motion associated with each wave *** superposition is carried out on all of the wave-maker motion components to get the final wave-maker *** the wave-maker motion as input,simulation of the single extreme irregular wave train is modeled *** the method is applied to simulating a much more complicated irregular wave *** again main features of the complicated irregular wave train are reproduced compared with experiment carried out in the new deepwater experimental basin at Shanghai Jiao Tong *** the simulation,dynamic mesh method is enabled to model the piston-type wave-maker,the Volume Of Fluid（VOF） method is employed to capture the free surface and a dissipation zone is introduced to deal with wave reflection.

关键词： numerical wave tank irregular wave train Volume of Fluid (VOF) dynamic mesh

Preparation and Characterization of Microcapsules for Self-healing Materials

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Chemical Research in Chinese Universities 2010年第3期26卷 496-500页

作者： liAO Le-ping ZHANG Wei ZHAO yang li Wu-jun National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 P. R. China

The urea-formaldehyde（UF） capsules filled with a healing agent, a mixture of epoxy resins（epoxy 711 and E-51） as core material, were produced by means of one step in-situ polymerization. The characteristics of these microcapsules were studied via scanning electron microscopy（SEM）, particle size analysis, FTIR and DSC/TGA. The results show that the dispersed and integrated microcapsules of 5 μm in shell thickness were synthesized successfully. The capsules were produced with diameters ranging from 10 to 250 μm via controlling agitation rate. Young＇s modulus of the capsule was a little lower than those of the epoxy resins, but the microcapsules having such a shell thickness were robust enough to survive handling during manufacturing self-healing composites. When damage occurred in the epoxy matrix, the crack could rupture the microcapsule to make the repairing agent release.

关键词： Urea-formaldehyde Microcapsule Epoxy resin Self-healing

Exact solution of Heisenberg model with site-dependent exchange couplings and Dzyloshinsky–Moriya interaction

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Chinese Physics B 2015年第10期24卷 460-466页

作者：杨丽君曹俊鹏杨文力 Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences Collaborative Innovation Center of Quantum Matter Institute of Modern Physics Northwest University Beijing Center for Mathematics and Information Interdisciplinary Sciences

We propose an integrable spin-1/2 Heisenberg model where the exchange couplings and Dzyloshinky-Moriya interactions are dependent on the sites. By employing the quantum inverse scattering method, we obtain the eigenvalues and the Bethe ansatz equation of the system with the periodic boundary condition. Furthermore, we obtain the exact solution and study the boundary effect of the system with the anti-periodic boundary condition via the off-diagonal Bethe ansatz. The operator identities of the transfer matrix at the inhomogeneous points are proved at the operator level. We construct the T -Q relation based on them. From which, we obtain the energy spectrum of the system. The corresponding eigenstates are also constructed. We find an interesting coherence state that is induced by the topological boundary.

关键词： Bethe ansatz yang-Baxter equation T-Q relation

Effect of expansive fillings on fracture seepage

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Mining Science and Technology 2009年第6期19卷 824-828页

作者： CHEN Jin-gang yang jun-li ZHANG Jing-fei Department of Engineering Mechanics Zhengzhou University Zhengzhou Henan 450001 China

Based on an investigation of the damage process of fractures filled with expansion media,samples of filling media collected on the spot,were obtained. The physical water properties of fracture fillings were tested by a WZ-2 type Dilatometer. Given our test results of the hydrated properties of fracture fillings and the mechanical parameters of altered rock mass collected from the Daye Iron Mine and comparisons between the expansion stress of fracture fillings and mechanical parameters of altered rock mass,the effects of the mechanical response of fillings on fracture seepage are discussed. The results show that the ratio of filling swell pressure to tensile strength of altered rock specimen varied between 11.79 and 36.77 and the ratio of filling swell pressure to shear strength of these rock specimen ranged from 72.11 to 171.18. Therefore,fillings have an important effect on fracture seepage,and the effect of deformation of the fracture caused by swell pressure of the filling mechanics cannot be ignored either. The multiple hydraulic coupling effects of fillings on the impact of fracture permeability are discussed according to theoretical analyses. It is shown that the effect of expansion of fracture fillings greatly affects the deformation of altered rock masses. Both tensile effect and shear effect produced by fracture fillings greatly increase the permeability of fractures. The plastic and liquefaction effects of fracture fillings also improve the permeability of fractures. On the basis of this analysis,a mechanical seepage model of filled fracture is established.

关键词： expansion filling medium fracture seepage