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Effect of Icosahedral Phase on crystallographic Texture and Mechanical Anisotropy of Mg–4%Li Based Alloys

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Journal of Materials Science & Technology 2017年第5期33卷 475-480页

作者： c.Q.Li D.K.Xu S.Yu L.Y.Sheng E.H.Han School of Materials Science and Engineering Northeastern University cAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering Shenyang Aerospace University Shenzhen Institute Peking University Shenzhen Key Lab Human Tissue Regenerate & Repair

Through investigating and comparing the microstructure and mechanical properties of the as-extruded Mg alloys Mg-4%Li and Mg-4%Li-6%Zn-l.2%Y （in wt%）, it demonstrates that although the formation of I-phase （Mg3Zn6Y, icosahedral structure） could weaken the crystallographic texture and improve the me- chanical strength, the mechanical anisotropy in terms of strength remains in Mg-4%Li-6%Zn-1.2%Y alloy. Failure analysis indicates that for the Mg-4%Li alloy, the fracture surfaces of the tensile samples tested along transverse direction （TD） contain a large number of plastic dimples, whereas the fracture surface exhibits quasi-cleavage characteristic when tensile samples were tested along extrusion direction （ED）. For the Mg-4%Li-6%Zn-I.2%Y alloy, typical ductile fracture surfaces can be observed in both ＂TD＂ and ＂ED＂ samples. Moreover, due to the zonal distribution of broken l-phase particles, the fracture surface of ＂TD＂ samples is characterized by the typical ＂woody fracture＂.

关键词： Mg-Li alloy Texture Mechanical anisotropy Fracture

Discriminated Dimensional Analysis Versus classical Dimensional Analysis and Applications to Heat Transfer and Fluid Dynamics

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chinese Journal of chemical Engineering 2007年第5期15卷 626-631页

作者： F. Alhama c.N. Madrid Department of Applied Physics Technical University of Cartagena Campus Muralla del Mar Cartagena 30203 Spain

In contrast to classical dimensional analysis, discriminated dimensional analysis assumes that spatial coordinates are dimensionally independent of each other and allows other types of geometrical quantity to be used in the dimensional basis, such as surfaces and angles. As a consequence, discriminated dimensional analysis leads to a lower number of dimensional groups, which makes the solution more precise. Besides, these discriminated groups have a clear physical meaning in terms of force and energy balances. The paper introduces this technique and provides dimensional equations for the main quantities and physical parameters of the heat transfer and fluid flow fields. Two applications are presented to demonstrate the efficiency of this method.

关键词： discriminated dimensional analysis heat transfer fluid dynamics dimensionless number

Symmetry-aware recursive image similarity exploration for materials microscopy

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npj computational Materials 2021年第1期7卷 1508-1521页

作者： Tri N.M.Nguyen Yichen Guo Shuyu Qin Kylie S.Frew Ruijuan Xu Joshua c.Agar Department of Materials Science and Engineering Lehigh UniversityBethlehemPA 18015USA Department of computer Science and Engineering Lehigh UniversityBethlehemPA 18015USA Department of Mechanical Engineering Lehigh UniversityBethlehemPA 18015USA Department of Applied Physics Stanford UniversityStanfordCA 94305USA

In pursuit of scientific discovery,vast collections of unstructured structural and functional images are acquired;however,only an infinitesimally small fraction of this data is rigorously analyzed,with an even smaller fraction ever being *** method to accelerate scientific discovery is to extract more insight from costly scientific experiments already ***,data from scientific experiments tend only to be accessible by the originator who knows the experiments and ***,there are no robust methods to search unstructured databases of images to deduce correlations and ***,we develop a machine learning approach to create image similarity projections to search unstructured image *** improve these projections,we develop and train a model to include symmetry-aware *** an exemplar,we use a set of 25,133 piezoresponse force microscopy images collected on diverse materials systems over five *** demonstrate how this tool can be used for interactive recursive image searching and exploration,highlighting structural similarities at various length *** tool justifies continued investment in federated scientific databases with standardized metadata schemas where the combination of filtering and recursive interactive searching can uncover synthesis-structure-property *** provide a customizable open-source package(https://***/m3-learning/Recursive_Symmetry_Aware_Materials_Microstructure_Explorer)of this interactive tool for researchers to use with their data.

关键词： interactive image similarity

Quantitative visualization of Taylor-couette flow with helical protrusion using optical and ultrasound imaging method

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排灌机械工程学报 2016年第10期34卷 829-834页

作者： KIM S.J. TU X.c. KIM H.B. School of Mechanical and Aerospace Engineering Gyeongsang National University Research center for Aircraft Parts Technology Gyeongsang National University

The simplified flow of drilling process in the soil hardening or oil rig site was experimentally investigated. Two flow models were used. One is the concentric cylinders with helical protrusion at the inner cylinder. The other is the concentric plain wall cylinders with axial flow. The radius ratio and aspect ratio of both models are the same with 0. 65 and 48,respectively. The mud is the typical fluid seen in the soil hardening processes. We used the water and the mud for the working fluid. We used the optical PIV for the water flow measurement and echo PIV for the mud flow. In case of the water study,the dominant vortical structures appeared in both the protrusion and plain model with axial *** case of mud flow,the vortices shown in the water model disappeared and the push and pull-up motion by the protrusion is dominant. We believe this information can be useful to understand the flow physics of drilling process in the complex fluid flow.

关键词： Taylor-couette flow surface protrusion echo PIV mud flow

A Quantitative Analysis of Mn Segregation at Partitioned Ferrite/Austenite Interface in a Fe-c-Mn-Si Alloy

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Journal of Materials Science & Technology 2009年第3期25卷 383-388页

作者： H. Guo S.W. Yang c.J.Shang X.M. Wang X.L. He Department of Materials Physics and chemistry University of Science and Technology Beijing Beijing 100083 China

Mn segregation at austenite/ferrite interface is studied in a Fe-c-Mn-Si alloy held at 656℃. Mn is partitioned during the growth of ferrite and as a result, a Mn pile-up exists in front of interface on the matrix side. An approach to evaluate Mn segregation quantitatively is developed by combining STEM raster window scanning and simulation of the interaction of the electron beam with the sample to subtract the contribution of Mn pile-up and obtain pure Mn segregation value. The evaluated maximum Mn interfacial segregation is in the order of a half-monolayer.

关键词： Interfacial segregation Phase transformation STEM Beam broadening

Biotinylated polyurethane-urea nanoparticles for targeted theranostics in human hepatocellular carcinoma

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Nano Research 2015年第5期8卷 1729-1745页

作者： Genoveva MorraI-Ruiz Pedro Melgar-Lesmes Andrea Lopez-Vicente conxita Solans Maria Jose garcia-celma Department of Pharmacy and Pharmaceutical Technology Faculty of Pharmacy University of Barcelona Av Joan XXIII s/n 08028 Barcelona Spain Institute of Advanced chemistry of catalonia (IQAc) CS/C Jordi Girona 18-26 08034 Barcelona Spain Networking Research center on Bioengineering Biomaterials and Nanomedicine CIBER-BBN Spain

Over the past years, significant efforts have been devoted to explore novel drug delivery and detection strategies for simultaneous therapy and diagnostics. The development of biotinylated polyurethane-urea nanoparticles as theranostic nanocarriers for targeted drug and plasmid delivery, for fluorescence detection of human hepatocellular carcinoma cells, is described herein. These targeted nanoparticles are specifically designed to incorporate biotin into the polymeric matrix, since many tumor types overexpress receptors for biotin as a mechanism to boost uncontrolled cell growth. The obtained nanoparticles were spherical, exhibited an average diameter ranging 110-145 nm, and showed no cytotoxicity in healthy endothelial cells. Biotinylated nanoparticles are selectively incorporated into the perinuclear and nuclear area of the human hepatocellular carcinoma cell line, HepG2, in division, but not into growing, healthy, human endothelial cells. Indeed, the simultaneous incorporation of the anticancer drugs, phenoxodiol or sunitinib, together with plasmid DNA encoding green fluorescent protein, into these nanoparticles allows a targeted pharmacological antitumor effect and furthermore, selective transfection of a reporter gene, to detect these cancer cells. The combined targeted therapy and detection strategy described here could be exploited for liver cancer therapy and diagnostics, with a moderate safety profile, and may also be a potential tool for other types of cancer.

关键词： cancer therapy DNA nanoparticles polyurethane theranostics

Time-Independent Finite Difference and Ghost cell Method to Study Sloshing Liquid in 2D and 3D Tanks with Internal Structures

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communications in computational Physics 2013年第3期13卷 780-800页

作者： c.H.Wu O.M.Faltinsen B.F.chen Department of Marine Environment and Engineering National Sun Yat-Sen UniversityKaohsiung 804Taiwan certre for Ships and Ocean Structures&Department of Marine Technology NTNUTrondheim 7491Norway

A finite difference scheme with ghost cell technique is used to study viscous fluid sloshing in 2D and 3D tanks with internal *** Navier-Stokes equations in a moving coordinate system are derived and they are mapped onto a time-independent and stretched *** staggered grid is used and the revised SIMPLEc iteration algorithm is *** developed numerical model is rigorously validated by extensive comparisons with reported analytical,numerical and experimental *** present numerical results were also validated through an experiment setup with a tank excited by an inclined horizontal excitation or a tank mounted by a vertical *** method is then applied to a number of problems including sloshing fluid in a 2D tank with a bottom-mounted baffle and in a 3D tank with a vertical *** phenomena of diagonal sloshing waves affected by a vertical plate are investigated in detail in this *** effects of internal structures on the resonant frequency of a tank with liquid are discussed and the present developed numerical method can successfully analyze the sloshing phenomenon in 2D or 3D tanks with internal structures.

关键词： Liquid sloshing baffle plate time-independent finite difference ghost cell

Deficiency of the transcription factor PLAG1 results in aberrant coiling and morphology of the epididymis

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Asian Journal of Andrology 2020年第4期22卷 342-347页

作者： Joanne Wong Almas R Juma Stephanie c Tran Jemma G Gasperoni Sylvia V H Grommen Bert De Groef Department of Physiology Anatomy and MicrobiologyLa Trobe UniversityBundooraVictoria 3086Australia

Mice deficient in the transcription factor pleomorphic adenoma gene 1(PLAG1)exhibit reproductive issues that are characterized,in part,by decreased progressive sperm motility in the ***,the underlying cause of this impairment is *** epididymal transit is critical for sperm maturation and motility,the morphology of the epididymis of Plag1-deficient mice was investigated and the spatial expression patterns of PLAG1 protein and mRNA were *** X-gal staining and in situ hybridization,PLAG1 was shown to be widely expressed in both the epithelium and stroma in all regions of the mouse ***,the X-gal staining pattern was markedly different in the cauda,where it could be suggestive of PLAG1 secretion into the epididymal *** all ages investigated,the morphology of epididymides from Plag1 knockout(KO)mice was aberrant;the tubule failed to elongate and coil,particularly in the corpus and cauda,and the cauda was malformed,lacking its usual bulbous ***,the epididymides from Plag1 KO mice were significantly reduced in size relative to body *** 20%of Plag1-deficient mice,the left testicle and epididymis were *** impaired morphogenesis of the epididymal tubule is likely to be a major contributing factor to the fertility problems observed in male Plag1-deficient *** results also establish PLAG1 as an important regulator of male reproduction,not only through its involvement in testicular sperm production,but also via its role in the development and function of the epididymis.

关键词： development epididymis pleomorphic adenoma gene 1 tubule coiling Wolffian duct

Plastic Strain Energy Model for Rock Salt Under Fatigue Loading

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Acta Mechanica Solida Sinica 2018年第3期31卷 322-331页

作者： M.M.He N.Li B.Q.Huang c.H.Zhu Y.S.chen Institute of Geotechnieal Engineering Xi'an University of TechnologyXi'an 710048China State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi'an University of TechnologyXi'an 710048China college of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650500China Shaanxi Key Laboratory of Loess Mechanics and Engineering Xi'an University of TechnologyXi'an 710048China

The fatigue test for rock salt is conducted to investigate the effects of stress ampli- tude, loading frequency and loading rate on the plastic strain energy, from which the evaluation rule of the plastic strain energy is analyzed, which is divided into three stages： cyclic hardening, saturation and cyclic softening. The total accumulated plastic strain energy only depends on the mechanical behavior of rock salt, but is immune to the loading conditions. A novel model for fatigue life prediction is proposed based on the invariance of the total plastic dissipation energy and the stability of the plastic energy per cycle.

关键词： Rock salt Fatigue life Plastic energy