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Effect of particle size of single-crystalline hierarchical ZSM-5 on its surface mass transfer in n-heptane catalytic cracking 被引量:2
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作者 Xiaoxue Zhang Shuman Xu +3 位作者 Jing Hao Xiaojin Xie Fengqiu Chen Dangguo Cheng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第11期148-157,共10页
Single-crystalline hierarchical ZSM-5 zeolites with different particle sizes(namely 100,140,and 200 nm)were successfully prepared by adjusting the amount of tetrapropylammonium hydroxide(TPAOH),and investigated in n-h... Single-crystalline hierarchical ZSM-5 zeolites with different particle sizes(namely 100,140,and 200 nm)were successfully prepared by adjusting the amount of tetrapropylammonium hydroxide(TPAOH),and investigated in n-heptane catalytic cracking reaction.Diffusional measurements by zero-length column(ZLC)method showed that the apparent diffusivities of n-heptane decreased with the reduction of particle size,indicating the existence of surface barriers.Moreover,with the decrease of particle size,the additional diffusion path length increased,which meant the influence of surface barriers became more apparent.Despite the change of surface barriers,the intracrystalline diffusion still dominated the overall diffusion.Catalytic performance showed that the zeolite with smaller particle size had better stability. 展开更多
关键词 SINGLE-CRYSTALLINE Hierarchical ZSM-5 particle size surface barriers n-Heptane catalytic cracking
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Reconstruction and stability of Fe_(3)O_(4)(001)surface:An investigation based on particle swarm optimization and machine learning
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作者 柳洪盛 赵圆圆 +2 位作者 邱实 赵纪军 高峻峰 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期27-31,共5页
Magnetite nanoparticles show promising applications in drug delivery,catalysis,and spintronics.The surface of magnetite plays an important role in these applications.Therefore,it is critical to understand the surface ... Magnetite nanoparticles show promising applications in drug delivery,catalysis,and spintronics.The surface of magnetite plays an important role in these applications.Therefore,it is critical to understand the surface structure of Fe_(3)O_(4)at atomic scale.Here,using a combination of first-principles calculations,particle swarm optimization(PSO)method and machine learning,we investigate the possible reconstruction and stability of Fe_(3)O_(4)(001)surface.The results show that besides the subsurface cation vacancy(SCV)reconstruction,an A layer with Fe vacancy(A-layer-V_(Fe))reconstruction of the(001)surface also shows very low surface energy especially at oxygen poor condition.Molecular dynamics simulation based on the iron–oxygen interaction potential function fitted by machine learning further confirms the thermodynamic stability of the A-layer-V_(Fe)reconstruction.Our results are also instructive for the study of surface reconstruction of other metal oxides. 展开更多
关键词 surface reconstruction magnetite surface particle swarm optimization machine learning
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The viscous strip approach to simplify the calculation of the surface acoustic wave generated streaming
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作者 F.JAZINI DORCHEH M.GHASSEMI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第4期711-724,共14页
In recent decades,the importance of surface acoustic waves,as a biocompatible tool to integrate with microfluidics,has been proven in various medical and biological applications.The numerical modeling of acoustic stre... In recent decades,the importance of surface acoustic waves,as a biocompatible tool to integrate with microfluidics,has been proven in various medical and biological applications.The numerical modeling of acoustic streaming caused by surface acoustic waves in microchannels requires the effect of viscosity to be considered in the equations which complicates the solution.In this paper,it is shown that the major contribution of viscosity and the horizontal component of actuation is concentrated in a narrow region alongside the actuation boundary.Since the inviscid equations are considerably easier to solve,a division into the viscous and inviscid domains would alleviate the computational load significantly.The particles'traces calculated by this approximation are excellently alongside their counterparts from the completely viscous model.It is also shown that the optimum thickness for the viscous strip is about 9-fold the acoustic boundary layer thickness for various flow patterns and amplitudes of actuation. 展开更多
关键词 surface acoustic wave MICROFLUIDICS numerical simulation particle tracing acoustic streaming
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Effective dynamics for a spin-1/2 particle constrained to a curved layer with inhomogeneous thickness
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作者 梁国华 尹佩林 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期78-83,共6页
We derive an effective Hamiltonian for a spin-1/2 particle confined within a curved thin layer with non-uniform thickness using the confining potential approach.Our analysis reveals the presence of a pseudo-magnetic f... We derive an effective Hamiltonian for a spin-1/2 particle confined within a curved thin layer with non-uniform thickness using the confining potential approach.Our analysis reveals the presence of a pseudo-magnetic field and effective spin–orbit interaction(SOI)arising from the curvature,as well as an effective scalar potential resulting from variations in thickness.Importantly,we demonstrate that the physical effect of additional SOI from thickness fluctuations vanishes in low-dimensional systems,thus guaranteeing the robustness of spin interference measurements to thickness imperfection.Furthermore,we establish the applicability of the effective Hamiltonian in both symmetric and asymmetric confinement scenarios,which is crucial for its utilization in one-side etching systems. 展开更多
关键词 curved surface inhomogeneous thickness spin-1/2 particle effective Hamiltonian
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Modification of Nano-α-Al2O3 and Its Influence on the Surface Properties of Waterborne Polyurethane Resin Composite Passivation Films
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作者 Jiankang Fu Changshuai Ma +2 位作者 Yameng Zhu Jing Yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第5期29-48,共20页
Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub&... Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> was determined by nano-particle size analyzer, and the effects of nano-α-Al<sub>2</sub>O<sub>3</sub> content, ethanol-aqueous solution ratio and KH560 dosage on the dispersion and particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> were investigated. The material structure before and after modification was determined by Fourier transform infrared spectroscopy (FTIR). Aqueous polyurethane resin and inorganic components are combined with modified nano-α-Al<sub>2</sub>O<sub>3</sub> dispersion to form chromium-free passivation solution. The solution is coated on the galvanized sheet, the adhesion and surface hardness are tested, the bonding strength of the coating and the surface hardness of the substrate are discussed. The corrosion resistance and surface morphology of the matrix were investigated by electrochemical test, neutral salt spray test and scanning electron microscope test. The chromium-free passivation film formed after the modification of nano-α-Al<sub>2</sub>O<sub>3</sub> increases the surface hardness of galvanized sheet by about 85%. The corrosion resistance of the film is better than that of a single polyurethane film. The results show that the surface hardness and corrosion resistance of polyurethane resin composite passivation film are significantly improved by the introduction of nano-α-Al<sub>2</sub>O<sub>3</sub>. 展开更多
关键词 Micro-Nano α-Al2O3 Waterborne Polyurethane Resin particle Size surface Hardness Corrosion Resistance
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Accurate Evaluation of Free-form Surface Profile Error Based on Quasi Particle Swarm Optimization Algorithm and Surface Subdivision 被引量:13
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作者 WEN Xiulan ZHAO Yibing +2 位作者 WANG Dongxia ZHU Xiaochun XUE Xiaoqiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期406-413,共8页
Although significant progress has been made in precision machining of free-form surfaces recently, inspection of such surfaces remains a difficult problem. In order to solve the problem that no specific standards for ... Although significant progress has been made in precision machining of free-form surfaces recently, inspection of such surfaces remains a difficult problem. In order to solve the problem that no specific standards for the verification of free-form surface profile are available, the profile parameters of free-form surface are proposed by referring to ISO standards regarding form tolerances and considering its complexity and non-rotational symmetry. Non-uniform rational basis spline(NURBS) for describing free-form surface is formulated. Crucial issues in surface inspection and profile error verification are localization between the design coordinate system(DCS) and measurement coordinate system(MCS) for searching the closest points on the design model corresponding to measured points. A quasi particle swarm optimization(QPSO) is proposed to search the transformation parameters to implement localization between DCS and MCS. Surface subdivide method which does the searching in a recursively reduced range of the parameters u and v of the NURBS design model is developed to find the closest points. In order to verify the effectiveness of the proposed methods, the design model is generated by NURBS and the measurement data of simulation example are generated by transforming the design model to arbitrary position and orientation, and the parts are machined based on the design model and are measured on CMM. The profile errors of simulation example and actual parts are calculated by the proposed method. The results verify that the evaluation precision of freeform surface profile error by the proposed method is higher 10%-22% than that by CMM software. The proposed method deals with the hard problem that it has a lower precision in profile error evaluation of free-form surface. 展开更多
关键词 profile error evaluation free-form surface quasi particle swarm optimization surface subdivision
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Osteoblast Behavior on Hierarchical Micro-/Nano-Structured Titanium Surface 被引量:7
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作者 Weiyan Meng Yanmin Zhou Yanjing Zhang Qing Cai Liming Yang Jinghui Zhao Chunyan Li 《Journal of Bionic Engineering》 SCIE EI CSCD 2011年第3期234-241,共8页
In the present work, osteoblast behavior on a hierarchical micro-/nano-structured titanium surface was investigated. A hi- erarchical hybrid micro-/nano-structured titanium surface topography was produced via Electrol... In the present work, osteoblast behavior on a hierarchical micro-/nano-structured titanium surface was investigated. A hi- erarchical hybrid micro-/nano-structured titanium surface topography was produced via Electrolytic Etching (EE). MG-63 cells were cultured on disks for 2 h to 7 days. The osteoblast response to the hierarchical hybrid micro-/nano-structured titanium surface was evaluated through the osteoblast cell morphology, attachment and proliferation. For comparison, MG-63 cells were also cultured on Sandblasted and Acid-etched (SEA) as well as Machined (M) surfaces respectively. The results show signifi- cant differences in the adhesion rates and proliferation levels of MG-63 cells on EE, SLA, and M surfaces. Both adhesion rate and proliferation level on EE surface are higher than those on SLA and M surfaces. Therefore, we may expect that, comparing with SLA and M surfaces, bone growth on EE surface could be accelerated and bone formation could be promoted at an early stage, which could be applied in the clinical practices for immediate and early-stage loadings. 展开更多
关键词 dental implant OSTEOBLAST hierarchical micro-/nano-structure surface treatment electrolytic etching
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Use of digital image analysis combined with fractal theory to determine particle morphology and surface texture of quartz sands 被引量:4
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作者 Georgia S.Araujo Kátia V.Bicalho Fernando A.Tristao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第6期1131-1139,共9页
The particle morphology and surface texture play a major role in influencing mechanical and hydraulic behaviors of sandy soils. This paper presents the use of digital image analysis combined with fractal theory as a t... The particle morphology and surface texture play a major role in influencing mechanical and hydraulic behaviors of sandy soils. This paper presents the use of digital image analysis combined with fractal theory as a tool to quantify the particle morphology and surface texture of two types of quartz sands widely used in the region of Vitória, Espírito Santo, southeast of Brazil. The two investigated sands are sampled from different locations. The purpose of this paper is to present a simple, straightforward,reliable and reproducible methodology that can identify representative sandy soil texture parameters.The test results of the soil samples of the two sands separated by sieving into six size fractions are presented and discussed. The main advantages of the adopted methodology are its simplicity, reliability of the results, and relatively low cost. The results show that sands from the coastal spit(BS) have a greater degree of roundness and a smoother surface texture than river sands(RS). The values obtained in the test are statistically analyzed, and again it is confirmed that the BS sand has a slightly greater degree of sphericity than that of the RS sand. Moreover, the RS sand with rough surface texture has larger specific surface area values than the similar BS sand, which agree with the obtained roughness fractal dimensions. The consistent experimental results demonstrate that image analysis combined with fractal theory is an accurate and efficient method to quantify the differences in particle morphology and surface texture of quartz sands. 展开更多
关键词 Quartz sands particle morphology and surface texture Image analysis Fractal theory
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Surface nanobubble characterization and its enhancement mechanisms for fine-particle flotation:A review 被引量:7
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作者 Fangyuan Ma Patrick Zhang Dongping Tao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第4期727-738,共12页
Froth flotation is often used for fine-particle separation,but its process efficiency rapidly decreases with decreasing particle size.The efficient separation of ultrafine particles(UFPs)has been a major challenge in ... Froth flotation is often used for fine-particle separation,but its process efficiency rapidly decreases with decreasing particle size.The efficient separation of ultrafine particles(UFPs)has been a major challenge in the mineral processing field for many years.In recent years,the use of surface nanobubbles in the flotation process has been recognized as an effective approach for enhancing the recovery of UFPs.Compared with traditional macrobubbles,nanobubbles possess unique surface and bulk characteristics,and their effects on the UFP flotation behavior have been a topic of intensive research.This review article is focused on the studies on various unique characteristics of nanobubbles and their mechanisms of enhancing the UFP flotation.The purpose of this article is to summarize the major achievements on the two topics and pinpoint future research needs for a better understanding of the fundamentals of surface nanobubble flotation and developing more feasible and efficient processes for fine and UFPs. 展开更多
关键词 surface nanobubbles CHARACTERIZATION FLOTATION ultrafine particles high-efficiency separation
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Dissipative Particle Dynamics Simulation on Bonding Reaction Between Surface Modified Nanoparticles 被引量:1
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作者 TANG Wei CHEN Peng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第1期91-97,共7页
A simulation study was carried out by using dissipative particle dynamics(DPD) method to explore the effects of properties of coating chains, such as length, density, rigidity of polymer chains, as well as the distanc... A simulation study was carried out by using dissipative particle dynamics(DPD) method to explore the effects of properties of coating chains, such as length, density, rigidity of polymer chains, as well as the distance between nanoparticles on bonding reaction of coating chains grafted onto nanoparticles. The results show that bonding ratios of coated chains strongly depend on the length and density of coating chains. For nanoparticles with different coating densities, the optimum chain length for bonding reaction are varied. The rigidity of coating chains exhibits vigorous effects on bonding reaction that highly depends on chain lengths. DPD simulation can be used to study the bonding reaction between coated nanoparticles, which may help experimental synthesis of nanocomposites with excellent properties. 展开更多
关键词 DISSIPATIVE particle dynamics(DPD) BONDING REACTION surface modified NANOparticleS coating CHAINS
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Computational modeling of free-surface slurry flow problems using particle simulation method 被引量:2
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作者 赵崇斌 彭省临 +2 位作者 刘亮明 B.E.Hobbs A.Ord 《Journal of Central South University》 SCIE EI CAS 2013年第6期1653-1660,共8页
The particle simulation method is used to solve free-surface slurry flow problems that may be encountered in several scientific and engineering fields.The main idea behind the use of the particle simulation method is ... The particle simulation method is used to solve free-surface slurry flow problems that may be encountered in several scientific and engineering fields.The main idea behind the use of the particle simulation method is to treat granular or other materials as an assembly of many particles.Compared with the continuum-mechanics-based numerical methods such as the finite element and finite volume methods,the movement of each particle is accurately described in the particle simulation method so that the free surface of a slurry flow problem can be automatically obtained.The major advantage of using the particle simulation method is that only a simple numerical algorithm is needed to solve the governing equation of a particle simulation system.For the purpose of illustrating how to use the particle simulation method to solve free-surface flow problems,three examples involving slurry flow on three different types of river beds have been considered.The related particle simulation results obtained from these three examples have demonstrated that:1) The particle simulation method is a promising and useful method for solving free-surface flow problems encountered in both the scientific and engineering fields;2) The shape and irregular roughness of a river bed can have a significant effect on the free surface morphologies of slurry flow when it passes through the river bed. 展开更多
关键词 particle simulation free surface slurry flow numerical method
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Modeling of contact surface morphology and dust particles by using finite element method 被引量:2
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作者 WANG Dong XU Liang-jun 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第3期403-407,共5页
The effect of dust particles on electric contacts and a hazardous size range of hard dust particles using a rigid model were discussed before. As further research, elastic-plastic model of finite element analysis was ... The effect of dust particles on electric contacts and a hazardous size range of hard dust particles using a rigid model were discussed before. As further research, elastic-plastic model of finite element analysis was established in this work, which is closer to real condition. In this work, the behavior of large size and small size particles, and the influence of particles hardness were investigated. The calculating result of small-size particles presents a general hazardous size coefficient for different contact surface morphology; for large-size particles, it presents a hazardous size coefficient for complicated composition of the dust. And the effect of the dust shape is also discussed. 展开更多
关键词 Dust particles surface morphology Finite element method (FEM) Hazardous size
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Milling Parameters Optimization of Al-Li Alloy Thin-Wall Workpieces Using Response Surface Methodology and Particle Swarm Optimization 被引量:2
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作者 Haitao Yue Chenguang Guo +2 位作者 Qiang Li Lijuan Zhao Guangbo Hao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第9期937-952,共16页
To improve the milling surface quality of the Al-Li alloy thin-wall workpieces and reduce the cutting energy consumption.Experimental research on the milling processing of AA2195 Al-Li alloy thin-wall workpieces based... To improve the milling surface quality of the Al-Li alloy thin-wall workpieces and reduce the cutting energy consumption.Experimental research on the milling processing of AA2195 Al-Li alloy thin-wall workpieces based on Response Surface Methodology was carried out.The single factor and interaction of milling parameters on surface roughness and specific cutting energy were analyzed,and the multi-objective optimization model was constructed.The Multiobjective Particle Swarm Optimization algorithm introducing the Chaos Local Search algorithm and the adaptive inertial weight was applied to determine the optimal combination of milling parameters.It was observed that surface roughness was mainly influenced by feed per tooth,and specific cutting energy was negatively correlated with feed per tooth,radial cutting depth and axial cutting depth,while cutting speed has a non-significant influence on specific cutting energy.The optimal combination of milling parameters with different priorities was obtained.The experimental results showed that the maximum relative error of measured and predicted values was 8.05%,and the model had high reliability,which ensured the low surface roughness and cutting energy consumption.It was of great guiding significance for the success of Al-Li alloy thin-wall milling with a high precision and energy efficiency. 展开更多
关键词 Al-Li alloy thin-wall workpieces response surface methodology surface roughness specific cutting energy multi-objective particle swarm optimization algorithm
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Simulation and experimental study on the surface morphology and energy lost of the target material under non-overlapping impact of angular particles 被引量:1
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作者 Xuewen Cao Chenyang Fu +2 位作者 Zhenqiang Xie Chao Wu Xiaoyang Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第1期47-56,共10页
In order to further understand the effect of solid impurities on pipeline wall during erosion,the particle impact process without fluid was extracted for specific study.The effect of multi-impact particles on the wall... In order to further understand the effect of solid impurities on pipeline wall during erosion,the particle impact process without fluid was extracted for specific study.The effect of multi-impact particles on the wall of pipeline was studied experimentally and simulated.In this experiment,an improved ejection apparatus was implemented to carry out multi-impacts non-overlapping impingement by rhombic particles made of high speed steel(W18Cr4V)on the AA6061 aluminum alloy plate through changing particle angle,incident angle,orientation angle and impact velocity.As a result,each particle's penetration depth was investigated and particles' rebound trajectory can be described through this experiment as well as surface morphology of the target material after impingement.The ductile damage criterion,shear damage criterion and MSFLD damage criterion were jointly implemented in ABAQUS/CAE software to simulate the whole process of collision which proved to be effective by getting consistent result compared with experimental data.It is found that under the condition of continuous non-overlapping impact,the target material produces a small work hardening effect in the impact area by converting kinetic energy of moving particles into internal energy of plate so as to reduce the penetration depth of each impact particle. 展开更多
关键词 Multi-impact experiment Angular particle surface morphology Energy lost ABAQUS/CAE simulation
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Reliability-based design optimization for flexible mechanism with particle swarm optimization and advanced extremum response surface method 被引量:1
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作者 张春宜 宋鲁凯 +2 位作者 费成巍 郝广平 刘令君 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第8期2001-2007,共7页
To improve the computational efficiency of the reliability-based design optimization(RBDO) of flexible mechanism, particle swarm optimization-advanced extremum response surface method(PSO-AERSM) was proposed by integr... To improve the computational efficiency of the reliability-based design optimization(RBDO) of flexible mechanism, particle swarm optimization-advanced extremum response surface method(PSO-AERSM) was proposed by integrating particle swarm optimization(PSO) algorithm and advanced extremum response surface method(AERSM). Firstly, the AERSM was developed and its mathematical model was established based on artificial neural network, and the PSO algorithm was investigated. And then the RBDO model of flexible mechanism was presented based on AERSM and PSO. Finally, regarding cross-sectional area as design variable, the reliability optimization of flexible mechanism was implemented subject to reliability degree and uncertainties based on the proposed approach. The optimization results show that the cross-section sizes obviously reduce by 22.96 mm^2 while keeping reliability degree. Through the comparison of methods, it is demonstrated that the AERSM holds high computational efficiency while keeping computational precision for the RBDO of flexible mechanism, and PSO algorithm minimizes the response of the objective function. The efforts of this work provide a useful sight for the reliability optimization of flexible mechanism, and enrich and develop the reliability theory as well. 展开更多
关键词 reliability-based design optimization flexible robot manipulator artificial neural network particle swarm optimization advanced extremum response surface method
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Particle Motion in Surface Gravity Waves 被引量:1
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作者 Kern E. Kenyon 《Natural Science》 2021年第2期18-20,共3页
Fluid particles in translating surface gravity waves have an orbital motion which decreases in size with increasing mean depth. These wave characteristics came from observations and were not forecast theoretically. Th... Fluid particles in translating surface gravity waves have an orbital motion which decreases in size with increasing mean depth. These wave characteristics came from observations and were not forecast theoretically. The classical potential flow model is incapable of explaining the particle movement due to the irrotational assumption and to a flaw in carrying out the method. When a wave passes by an observer from left to right, the particles move clockwise under a crest and a trough. This correct conclusion is consistent with what the incorrect standard theory implies but should not be considered to have been derived from it. 展开更多
关键词 surface Gravity Waves Orbital particle Motion
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Microstructure and wear characteristics of ATZ ceramic particle reinforced gray iron matrix surface composites 被引量:3
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作者 Xue Ma Liang-feng Li +3 位作者 Fan Zhang Zu-hua Zhang Hao Wang En-ze Wang 《China Foundry》 SCIE 2018年第3期167-172,共6页
The alumina toughened zirconia(ATZ) ceramic particle reinforced gray iron matrix surface composite was successfully manufactured by pressureless infi ltration. The porous preform played a key role in the infi ltrating... The alumina toughened zirconia(ATZ) ceramic particle reinforced gray iron matrix surface composite was successfully manufactured by pressureless infi ltration. The porous preform played a key role in the infi ltrating progress. The microstructure was observed by scanning electron microscopy(SEM); the phase constitutions was analyzed by X-ray diffraction(XRD); and the hardness and wear resistance of selected specimens were tested by hardness testing machine and abrasion testing machine, respectively. The addition of high carbon ferrochromium powders leads to the formation of white iron during solidifi cation. The wear volume loss rates of ATZ ceramic particle reinforced gray iron matrix surface composite decreases fi rst, and then tends to be stable. The wear resistance of the composite is 2.7 times higher than that of gray iron matrix. The reason is a combination of the surface hardness increase of gray iron matrix and ATZ ceramic particles and alloy carbides protecting effect on gray iron matrix. 展开更多
关键词 metal-matrix surface composites pressureless infiltrating particle-REINFORCEMENT surface ALLOYING WEAR testing
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Surface tension of lithium bromide aqueous solution/ammonia with additives and nano-particles 被引量:3
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作者 蔡伟华 孔伟伟 +2 位作者 王悦 朱蒙生 王新雷 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1979-1985,共7页
In order to investigate the effect of additives and nano-particle on the surface tensions of lithium bromide(Li Br) aqueous solution/ammonia, many experiments were carried out based on Wilhelmy plate method. Firstly, ... In order to investigate the effect of additives and nano-particle on the surface tensions of lithium bromide(Li Br) aqueous solution/ammonia, many experiments were carried out based on Wilhelmy plate method. Firstly, the surface tension of Li Br aqueous solution with 1-octanol was measured and then the comparison between the measured results and previous experimental results was given to verify the measuring accuracy. Some new additives, such as cationic surfactants cetyltrimethyl ammonium chloride(CTAC), and cetyltrimethyl ammonium bromide(CTAB) were chosen in the experiments. The experimental results show that CTAC and CTAB can obviously reduce the surface tension of Li Br aqueous solution/ammonia. In addition, it is found that nano-particles cannot remarkably decrease the surface tension of Li Br aqueous solution/ammonia. However, the mixed addition of additives and nano-particles can remarkably affect the surface tension of Li Br aqueous solution/ammonia. That is to say, additives play more important role in reducing the surface tension of Li Br aqueous solution/ammonia. But nano-particles may enhance the heat transfer in the absorption refrigeration process. 展开更多
关键词 lithium bromide AMMONIA ADDITIVES NANO-particleS surface tension
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Surface Modification of a-Fe Metal Particles by Chemical Surface Coating
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作者 Qixiang WANG, Baozhen SONG and Hongzhong LIInstitute of Process Engineering, Chinese Academy of Sciences, Beijing 100080, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第2期155-157,共3页
The structure of a-Fe metal magnetic recording particles coated with silane coupling agents have been studied by TEM, FT-IR, EXAFS, Mossbauer. The results show that a close, uniform, firm and ultra thin layer, which i... The structure of a-Fe metal magnetic recording particles coated with silane coupling agents have been studied by TEM, FT-IR, EXAFS, Mossbauer. The results show that a close, uniform, firm and ultra thin layer, which is beneficial to the magnetic and chemical stability, has been formed by the cross-linked chemical bond Si-O-Si. And the organic molecule has chemically bonded to the particle surface, which has greatly affected the surface Fe atom electronic structure. Furthermore, the covalent bond between metal particle surface and organic molecule has obvious effect on the near edge structure of the surface Fe atoms. 展开更多
关键词 Magnetic recording particles a-Fe EXAFS MOSSBAUER Chemical surface coating
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STRUCTURE AND SURFACE CONDITION OF ULTRAFINE AI PARTICLES
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作者 SUN Xiukui CHEN Wenxiu XU Jian FAN Xueshu WEI Wenduo State Key Laboratory of Rapidly Solidified Non-Equilibrium Alloys,Institute of Metal Research,Academia Sinica,Shenyang,ChinaWU Yukun PENG Yingguo Laboratory of Atomic Imaging of Solids,Institute of Metal Research,Academia Sinica,Shenyang,China Associate Professor,Institute of Metal Research,Academia Sinica,Shenyang 110015,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1992年第6期402-408,共7页
The crystal habit,crystalline structure,surface condition and composition of the ultrafine Al particles prepared by inert gas evaporation method were studied in detail by means of high resolution transmission electron... The crystal habit,crystalline structure,surface condition and composition of the ultrafine Al particles prepared by inert gas evaporation method were studied in detail by means of high resolution transmission electron microscope,X-ray diffraction and X-ray photo-electron spectrum.The results indicate that the ultrafine Al particles prepared in high pure inert gas are of clear crystal habits,single crystal in a large majority and fcc crystalline structure with a_0=0.405 nm.It is also found on the surface of the Al particles that there is a layer of amor- phous Al_2O_3 with 2 nm average thickness,which could protect the particles against oxidizing further.Therefore,the ultrafine Al particles prepared by the inert gas evaporation method are very stable in atmosphere. 展开更多
关键词 ultrafine Al particle STRUCTURE surface condition amorphous alumina
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