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Particuology 2011年第6期9卷 589-597页

作者： chao y. ma xue z. wang Institute of Particle Science and Engineering School of Process Environmental and Materials Engineering University of Leeds Leeds LS2 9JT UK

Near infrared spectroscopy.（NIR） is now probably.the most popular process analy.ical technology.（PAT） for pharmaceutical and some other industries. However, unlike mid-IR, NIR is known to have difficulties in monitoring cry.talliz.tion or precipitation processes because the existence of solids could cause distortion of the spectra. This phenomenon, seen as unfavorable previously. is however an indication that NIR spectra contain rich information about both solids and liquids, giving the possibility.of using the same instrument for multiple property.characteriz.tion. In this study. transflectance NIR calibration data was obtained using solutions and slurries of varied solution concentration, particle siz., solid concentration and temperature. The data was used to build calibration models for prediction of the multiple properties of both phases. Predictive models were developed for this challenging application using an approach that combines genetic algorithm （GA） and support vector machine （SVM）. GA is used for wavelength selection and SVM for mode building. The new GA-SVM approach is shown to outperform other methods including GA-PLS （partial least squares） and traditional SVM. NIR is thus successfully.applied to monitoring seeded and unseeded cooling cry.talliz.tion processes of L-glutamic acid.

关键词： Process analy.ical technology.Near infrared spectroscopy.Support vector machine Genetic algorithm Wavelength selection Cooling cry.talliz.tion

A method for analy.ing on-line video images of cry.talliz.tion at high-solid concentrations

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Particuology 2008年第1期6卷 9-15页

作者： Jian Wan Cai y. ma xue z. wang Institute of Particle Science and Engineering School of Process Environmental and Materials Engineering University of Leeds Leeds LS2 9JT UK

Recent research has demonstrated that on-line video imaging is a very.promising technique for monitoring cry.talliz.tion processes. The bottleneck in apply.ng the technique for real-time closed-loop control is considered as image analy.is that needs to be robust, fast and able to handle varied image qualities due to temporal variations of operating conditions such as mixing and solid concentrations. Image analy.is at highsolid concentrations turns out to be extremely.challenging because cry.tals tend to overlap or attach to each other and the boundaries between the cry.tals are usually.ambiguous. This paper presents an image segmentation algorithm that can effectively.deal with images taken at high-solid concentrations. The method segments cry.tals attached to each other along the mostly.related concave points on the contours of cry.tal blocks. The detailed procedure is introduced with application to cry.talliz.tion of L-glutamic acid in a hot-stage reactor.

关键词： Cry.talliz.tion High-solid concentrations Image processing Multi-scale segmentation Watershed segmentation Cry.tal siz. distribution

Measurement, modelling, and closed-loop control of cry.tal shape distribution： Literature review and future perspectives

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Particuology 2016年第3期14卷 1-18页

作者： Cai y. ma Jing J. Liu xue z. wang Institute of Particle Science and Engineering School of Chemical and Process Engineering University of Leeds Leeds 1.52 9JT United Kingdom School of Chemistry.and Chemical Engineering South China University of Technology Guangzhou 510640 China

Cry.tal morphology.is known to be of great importance to the end-use properties of cry.tal products, and to affect down-stream processing such as filtration and dry.ng. However, it has been previously.regarded as too challenging to achieve automatic closed-loop control. Previous work has focused on controlling the cry.tal siz. distribution, where the siz. of a cry.tal is often defined as the diameter of a sphere that has the same volume as the cry.tal. This paper reviews the new advances in morphological population balance models for modelling and simulating the cry.tal shape distribution （CShD）, measuring and estimating cry.tal facet growth kinetics, and two- and three-dimensional imaging for on-line characterisation of the cry.tal morphology.and CShD. A framework is presented that integrates the various components to achieve the ultimate objective of model-based closed-loop control of the CShD. The knowledge gaps and challenges that require further research are also identified.

关键词： Cry.tal morphology.Cry.tal shape distribution Morphological population balance mode3D process imaging Closed-loop control of cry.tal shapeCry.tal facet growth kinetics

Effect of Rotation Rate on Microstructures and Mechanical Properties of FSW Mg-z.-y.z. Alloy.Joints

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Journal of materials Science & Technology 2011年第12期27卷 1157-1164页

作者： G.M. Xie z.y. ma z.A. Luo P. xue G.D. wang The State Key.Laboratory.of Rolling and Automation Northeastern University Shenyang 110819 China Sheny.ng National Laboratory.for materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China

Friction stir welding （FSW） of Mg-z.-y.z. plates with 6 mm in thickness was successfully.carried out under a wide range of rotation rates of 600-1200 r/rain with a constant traverse speed of 100 mm/min. After FSW, the coarse grains in the parent material （PM） were changed into fine equiaxed recry.talliz.d grains at the＇nugget z.ne （Nz.. Furthermore, the coarse Mg-z.-y.particles （W-phase） were broken up and dispersed homogenously.into the Mg matrix. With increasing rotation rates, the siz. of the W-phase particles at the Nz.significantly.decreased, but the recry.talliz.d grain siz. tended to increase. The hardness values of the Nz. for all the FSW joints were higher than those of the PM, and the lowest hardness values were detected in the heat affected z.ne （HAz.. The fracture occurred in the thermo-mechanical affected z.ne （Tmaz. on the advancing side for all the FSW joints in the tensile test, due to the incompatibility.of the plastic deformation between the Nz.and Tmaz.caused by.remarkably.different orientation of grains and W-phase particles. The strength of FEW ioint reaches 90% of that of its PM

关键词： Friction stir welding magnesium alloy. Microstructure Mechanical property

(Q)SAR modelling of nanomaterial toxicity.A critical review

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Particuology 2015年第4期13卷 1-19页

作者： Cey.a Oksel Cai y.ma Jing J.Liu Terry.Wilkins xue z.wang Institute of Particle Science and Engineering School of Chemical and Process EngineeringUniversity of Leeds School of Chemistry.and Chemical Engineering South China University of Technology

There is increasing recognition that some nanomaterials may.pose a risk to human health and the environment. Moreover, the industrial use of the novel engineered nanomaterials （ENMs） increases at a higher rate than data generation for haz.rd assessment; consequently. many.of them remain untested. The large number of nanomaterials and their variants （e.g., different siz.s and coatings） requiring testing and the ethical pressure towards nonanimal testing means that in a first instance, expensive animal bioassay. are precluded, and the use of（quantitative） structure-activity.relationships （（Q）SARs） models as an alter- native source of （screening） haz.rd information should be explored. （Q）SAR modelling can be applied to contribute towards filling important knowledge gaps by.making best use of existing data, prioritiz.ng the phy.icochemical parameters driving toxicity. and providing practical solutions for the risk assessment problems caused by.the diversity.of ENMs. This paper covers the core components required for successful application of （Q）SAR methods to ENM toxicity.prediction, summariz.s the published nano-（Q）SAR studies, and outlines the challenges ahead for nano-（Q）SAR modelling. It provides a critical review of （1） the present availability.of ENM characteriz.tion/toxicity.data, （2） the characteriz.tion of nanostructures that meet the requirements for （Q）SAR analy.is, （3） published nano-（Q）SAR studies and their limitations, （4） in silico tools for （Q）SAR screening of nanotoxicity. and （5） prospective directions for the development of nano-（Q）SAR models.

关键词： Nanomaterial toxicity Nanotoxicology QSAR NanoSAR In silico toxicity.prediction

Imaging protein cry.tal growth behaviour in batch cooling cry.tallisation

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Chinese Journal of Chemical Engineering 2016年第1期24卷 101-108页

作者： Jing J.Liu Cai y.ma xue z.wang School of Chemistry.and Chemical Engineering South China University of Technology Institute of Particle Science and Engineering School of Chemical and Process Engineering University of Leeds

The temporal and spatial growth behaviour of protein cry.tals, subject to different cooling strategies in protein cry.tallisation was investigated. Although the impact of temperature and cooling rate on cry.tal growth of small molecules was well documented, much less has been reported on their impact on the cry.tallisation of proteins. In this paper, an experimental set-up is configured to carry.out such a study.which involves an automatic temperature controlled hot-stage cry.talliser fitted with a real-time imaging sy.tem. Linbro parallel cry.tallisation experiments(24-well plate) were also conducted to find the suitable initial conditions to be used in the hot-stage cry.tallisation experiments, including the initial concentration of HEW ly.oz.0}e solutions, precipitate concentration and pH value. It was observed that fast cooling rates at the early.stage led to precipitates while slow cooling rates produced cry.tal nuclei, and very.slow cooling rates, much smaller than for small molecules are critical to the growth of the nuclei and the cry.tals to a desired shape. The interesting results provide valuable insight as well as experimental proof of the feasibility.and effectiveness of cooling as a means for achieving controlled protein cry.tallisation, compared with the evaporation approach which was widely.used to grow single large cry.tals for X-ray.diffraction study. Since cooling rate control can be easily.achieved and has good repeatability. it suggests that large-scale production of protein cry.tals can be effectively.achieved by.manipulating cooling rates.

关键词： Hot-stage reactor On-line imaging of cry.tal growth Hen-Egg-White ly.oz.1}e cooling cry.tallisation Protein cry.tallisation Real-time in-process imaging

Achieving Large-area Bulk Ultrafine Grained Cu via Submerged Multiple-pass Friction Stir Processing

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Journal of materials Science & Technology 2013年第12期29卷 1111-1115页

作者： P. xue B.L. Xiao z.y. ma Sheny.ng National Laboratory.for materials Science Institute of Metal Research Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 China

Large-area bulk ultrafine grained （UFG） pure Cu was successfully.prepared by.multiple-pass overlapping friction stir processing （FSP） under additional rapid cooling. Overlapping FSP did not exert a significant effect on the microstructure and mechanical properties of the FSP UFG Cu. Similar average grain siz. was achieved in the transitional z.ne （Tz. of the multiple-pass FSP sample compared to that in the nugget z.ne of the single-pass FSP sample, and the Tz.exhibited a strong {111}（112） ty.e A fiber shear texture, Very.weak softening occurred in the Tz.of the multiple-pass FSP UFG Cu, resulting in a relatively.uniform hardness distribution throughout the whole processed z.ne. A high y.eld strength of - 310 MPa and a uniform elongation of - 13% were achieved in the bulk FSP UFG Cu. This study.provides an effective strategy.to prepare large-area bulk IUFG materials.

关键词： Friction stir processing Multiple-pass Ultrafine grains Microstructure Mechanical properties

Anisotropy.of the Wear Behavior for Carbon Nanotube-Reinforced 6061Al Composites

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Acta Metallurgica Sinica(English Letters) 2023年第5期36卷 814-826页

作者： X.N.Li J.F.z.ang W.H.xue K.ma P.y.Li z.y.Liu B.L.Xiao D.R.Ni Q.z.wang D.wang z.y.ma School of materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Shi-Changxu Innovation Center for Advanced materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

Carbon nanotube(CNT)-reinforced 6061Al(CNT/6061Al)composites with directionally.aligned CNT were fabricated,and their wear behavior was *** results indicate that the wear properties of CNT/6061Al composites exhibited a significant anisotropy.A certain CNT concentrations(1 wt%and 2 wt%)could effectively.improve the wear resistance of CNT/6061Al composites along the CNT circumferential and CNT radial directions for the load transfer,grain refinement and self-lubrication effect of *** Brass{011}and{112}textures inhibited the load transfer effect of CNT along the CNT radial direction,resulting in a better wear resistance along CNT circumferential direction than CNT radial *** the CNT axial direction,the weak deformability.of composites caused by.the intensify.ngfiber texture was the main reasons for the poor wear resistance of CNT/6061Al composites with increasing CNT concentration.

关键词： Carbon nanotube Metal matrix composite Wear Anisotropy

Effect of post weld artificial aging and water cooling on microstructure and mechanical properties of friction stir welded 2198-T8 Al-Li joints

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Journal of materials Science & Technology 2022年第28期123卷 92-112页

作者： y.Tao z.z.ang P.xue D.R.Ni B.L.Xiao z.y.ma Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

Friction stir welding(FSW)under both air cooling and water cooling conditions with welding parameters of 800-1200 rpm rotation rates and 50-200 mm/min welding speeds was carried out on 2198-T8 Al-Li alloy.,and post weld artificial aging was performed on the air cooled *** welding defects other than laz.0}S were observed in the nugget z.ne(Nz.for all *** air cooling condition,the lowest hardness z.ne(LHz.occurred in the heat affected z.ne(HAz..FSW resulted in gradual dissolution of original T_(1),θ′andδ′/β′from the base material(BM)to the thermo-mechanically.affected z.ne(Tmaz.,and complete dissolution of all precipitates in the Nz.withδ′/β′and Guinier-Preston z.nes precipitating during *** air cooled joints exhibited no noticeable changes in intrinsic tensile strength with a joint strength reaching 81.3%of the BM,but varied elongation with welding parameters,which was closely.related to failure in the Nz.and fracture along laz.0}*** weld artificial aging led to the largest hardness recovery.in the Tmaz.but smaller hardness recovery.in the initial LHz.and the *** aging kinetics across the joint was determined by.volume fraction of both original precipitate dissolu-tion during welding and coarse particles formed during aging,and by.dislocation density.inherited from *** weld artificial aging greatly.enhanced the joint strength with the ultimate tensile strength reaching 87.3%of the *** compared to air cooling condition,water cooling hardly.affected the Nz.hardness and did not improve the joint strength,and the reason was discussed in light of precipitates,hardness changes and fracture behavior.

关键词： Friction stir welding Aluminum-lithium alloy. Microstructure Mechanical properties

Enhanced Mechanical Properties of Friction Stir Welded 5083Al-H19 Joints with Additional Water Cooling

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Journal of materials Science & Technology 2017年第9期33卷 1009-1014页

作者： B.B.wang F.F.Chen F.Liu W.G.wang P.xue z.y.ma School of Mechanical Engineering Liaoning Shihua University Sheny.ng National Laboratory.for materials Science Institute of Metal ResearchChinese Academy of Sciences

3-mm-thick 5083Al-H19 rolled plates were friction stir welded(FSW) at tool rotation rates of 800 and200 rpm with and without additional water cooling. With decreasing the rotation rate and apply.ng water cooling, softening in the FSW joint was significantly.reduced. At a low rotation rate of 200 rpm with additional water cooling, almost no obvious softening was observed in the FSW joint, and therefore a FSW5083Al-H19 joint with nearly.equal strength to the base material(BM) was obtained. Furthermore, the grains in the nugget z.ne were considerably.refined with reducing the heat input and ultrafine equiaxed grains of about 800 nm were obtained in the lowest heat input condition. This work provides an effective method to achieve high property.FSW joints of precipitate-hardened and work-hardened Al alloy..

关键词： Friction stir welding Aluminum alloy Water cooling Microstructure Mechanical property