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Dissolution of Al_2TiO_5 inclusions in CaO-SiO_2-Al_2O_3 slags at 1823 K

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International Journal of Minerals,Metallurgy and materials 2011年第6期18卷 646-651页

作者： De-yong Wang Jun Liu Mao-fa Jiang Fumitaka Tsukihashi Hiroyuki Matsuura School of materials and Metallurgy Northeastern University Shenyang 110004 China department of Advanced materials Science Graduate School of Frontier Sciences Tokyo University Chiba 277-8561 Japan

Al-Ti-O inclusions always clog submerged nozzles in Ti-bearing Al-killed steel.A typical synthesized Al2TiO5 inclusion was immersed in a CaO-SiO2-Al2O3 molten slag for different durations at 1823 *** Al2TiO5 dissolution paths and mechanism were revealed by scanning electron microscopy （SEM） and energy dispersive spectroscopy （EDS）.Decreased amounts of Ti and Al and increased amounts of Si and Ca at the dissolution boundary prove that inclusion dissolution and slag penetration simultaneously ***2 diffuses or penetrates the inclusion more quickly than CaO,as indicated by the w（CaO）/w（SiO2） value in the reaction region.A liquid product （containing 0.7-1.2 w（CaO）/w（SiO2）,15wt%-20wt% Al2O3,and 5wt%-15wt% TiO2） forms on the inclusion surface when Al2TiO5 is dissolved in the ***2TiO5 initially dissolves faster than the diffusion rate of the liquid product toward the bulk *** increasing reaction time,the boundary reaches its largest distance,the Al2TiO5 dissolution rate equals the liquid product diffusion rate,and the dissolution process remains stable until the inclusion is completely dissolved.

关键词： steelmaking aluminium titante molten slag inclusions dissolution

Polymer composite for antistatic application in aerospace

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Defence Technology（防务技术） 2020年第1期16卷 107-118页

作者： Ramdayal Yadav Manoj Tirumali Xungai Wang Minoo Naebe Balasubramanian Kandasubramanian Institute for frontier materials Deakin UniversityWaurn PondsVIC3216Australia department of Metallurgical and materials Engineering Defence Institute of Advanced Technology(DU)GirinagarPune411025India

The pheno menon of static electricity is unpredictable,particulariy when an aircraft flying at high altitude that causes the accumulation of static charges beyond a threshold value leading to the failure of its parts and systems including severe explosion and radio communication *** accumulation of static charges on aircraft is generated by the virtue of interaction between the outer surface of aircraft and the external environmental attributes encompasses air particles,ice,hail,dust,volcanic ash in addition to its triboelectric *** the recent years,advanced polymer-based composites or nanocomposites are preferred structural constituents for aircrafts due to their light weight and comparable mechanical properties,but such composite systems do not render low impedance path for charge flow and are subsequently vulnerable to effect of lightning strike and precipitation *** this context,it is essential to develop conductive composite systems from non-co nductive polymer natrix by nano fillerembodime *** advent of carbon-based nanocomposite/nano materials have adequately addressed such issues related to the nonco nductive polymer matrix and further turned into an avant-garde genre of *** current review envisioned to illustrate the detailed exploitation of various polymer nanocomposites in addition to especially mentioned epoxy composites based on carbon fillers like carbon black,carbon nanotube(single walled carbon nanotube and multi walled carbon nanotube) and graphene the development of antistatic application in aircra ft in addition to the static charge phenomenon and condition for its prevalence in avionic systems.

关键词： Static discharge system Nanocomposite Anti-static materials Electromagnetic interference Aerospace applications

Large Eddy Simulation for Unsteady Turbulent Field in Thin Slab Continuous Casting Mold

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Journal of Iron and Steel Research International 2011年第S2期18卷 243-250页

作者： Fumitaka Tsukihashi department of Advanced materials Science Graduate School of Frontier Science University of Tokyo Kashiwa 277-8561 Japan

The unsteady turbulent flow during the continuous casting of steel is important, because it influences critical phenomena that affect steel quality. Unsteady three-dimensional flow in the mold region of the liquid pool during continuous casting of steel slabs has been computed using realistic geometries starting from the submerged inlet nozzle to the mold. The cassette filter function was used to deal with unsteady Navier-Stokes equation, and then the turbulent flow in the thin slab CCM was simulated with the large eddy simulation method combined with the Smagorinsky sub-grid scale model in this paper. And the model was verified by the Particle Image Velocimetry (PIV) experimental results which was got from a relate scientific literature. In this thesis, by means of LES, the flow characteristics in the thin slab CCM were acquired, such as the vortex distribution, the formation of the large eddy coherent structures, development, shedding and fracture process. In the same time, the turbulent asymmetric distribution was revealed even the nozzle in the centre position. Interactions between the two halves cause large velocity fluctuations near the meniscus. And the vortex is located at the low velocity side adjacent to the SEN. Along with the unsteady time development, the unsteady turbulent large vortex structures of the liquid steel in the CCM presented periodic bias flow distribution, and the period is about 20 seconds.

关键词： continuous casting mold unsteady large eddy simulation vortex coherent structures

Study of Argon/Molten Steel Two-Phase Flow in Refining of High Clean Steel Using Two-Fluid Model

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Journal of Iron and Steel Research International 2011年第S2期18卷 176-181页

作者： TSUKIHASHI Fumitaka department of Advanced materials Science Graduate School of Frontier Science University of Tokyo Kashiwa 277-8561 Japan

RH vacuum degasser is a very important secondary refining device in the production of high quality steels. The flow field of molten steel in RH system plays a significant role in determining productivity of the equipment. The homogeneous model and VOF method were often used to predict the flow field in RH system, but these kinds of models simplified the interaction between gas bubbles and molten steel. In the present work, a numerical model of a whole RH system, including vacuum degasser, immersed legs and ladle,was built based on gas-liquid two-fluid model, and it could be used to analyze the interaction between argon bubbles and molten steel, to understand the effect of the bubble size to the flow field.

关键词： RH vacuum degasser gas-liquid two-phase flow two-fluid model interaction

Plasma-Assisted Antimicrobial Finishing of Textiles: A Review

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Engineering 2022年第5期8卷 145-163页

作者： Maryam Naebe Abu Naser Md Ahsanul Haque Aminoddin Haji Deakin University Institute for Frontier MaterialsGeelongVIC 3216Australia Textile Engineering department Yazd UniversityYazd 89138-75639Iran

Owing to the ongoing pandemic,the importance of and demand for antimicrobial textiles have reached new *** addition to being used for medical purposes,antimicrobial textiles could be a self-defense entity against microbes for the general *** textiles are widely used,they can effectively be used to prevent the spread of microbes *** conventional antibacterial finishing process of textiles is the wet treatment method using either the pad–dry–cure or exhaustion ***,the textile wet treatment industries are major contributors to worldwide pollution,which is extremely *** the current and near-future high demand,it is imperative to include plasma in antimi-crobial finishing to achieve high efficiency in production,while retaining a safe ***,this paper reviews the rationale of plasma use in textile antimicrobial finishing through a critical analysis of recent studies and emphasizes the types and mechanisms of plasma techniques available for application.

关键词： Plasma Grafting Polymerization Sputtering Nanomaterials Antimicrobial

Modified Triphenylmethane-based Polyimides with Improved Optical,Dielectric and Solubility Properties via Post-Polymerization Modification

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Chinese Journal of Polymer Science 2023年第10期41卷 1609-1616页

作者： Yan-Cheng Wu Guo-Tao Huang Man-Yu Lian Rui Liang Hong-Lin Deng Feng Gan Yang-Fan Zhang Ning-Bo Yi Li-Yong Tian Chun-Ping Ma Yen Wei School of Textile materials and Engineering Wuyi UniversityJiangmen529020China department of Chemistry and the Tsinghua Center for frontier Polymer Research Tsinghua UniversityBeijing100084China

A family of new triphenylmethane(TPM)-based polyimides(PIs)containing bulky tert-butyldimethylsiloxy(TBS)side-groups(PI-TPMOSis)has been prepared by a post-polymerization modification via a simple silyl ether reaction of TPM-based PIs containing hydroxyl(OH)groups(PI-TPMOHs).The attachment of TBS side-groups in PI-TPMOSis can be achieved up to 100%,as confirmed by the 1H-NMR and IR *** to the presence of the TPM structure,PI-TPMOSi films still display the excellent thermal stability with high glass transition temperature(Tg)of 314–351°C and high degradation temperature(Td5%)of 480–501°*** is quite remarkable that the introduction of TBS side-groups into PI-TPMOSi chains results in more superior optical,dielectric and solubility properties in comparison with the precursor PI-TPMOH films,probably due to the reductions of the packing density and charge-transfer complexes(CTCs)*** optical transmittance at 400 nm(T400)of PI-TPMOSi films is significantly increased from 45.3%–68.8%to 75.4%–81.6%of the precursor PI-TPMOH *** dielectric constant(Dk)and dissipation factor(Df)at 1 MHz of PI-TPMOSi films are reduced from 4.11–4.40 and 0.00159–0.00235 to 2.61–2.92 and 0.00125–0.00171 of the precursor PI-TPMOH films,*** the molecular design and simple preparation method,this study provides an effective approach for enhancement of various properties of PI films for microelectronic and photoelectric engineering applications.

关键词： Triphenylmethane-based polyimides Post-polymerization modification High Tg High optical transparence Low Dk

Tetraphenylethene End-capped Polyethylenimine Fluorescent Nanoparticles for Cell Imaging

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Chinese Journal of Polymer Science 2014年第11期32卷 1479-1488页

作者：张锡奇 Xiao-yong Zhang Bin Yang 危岩 department of Chemistry and the Center for frontier Polymer Research Tsinghua University

Water soluble tetraphenylethene-based（TPE） aggregation-induced emission fluorescent organic nanoparticles（FONs） were facilely prepared via Schiff base condensation with polyethylenimine（PEI） and subsequent reduction. The obtained TPE-PEI FONs were characterized by a series of techniques including 1H-NMR, 13C-NMR, gel permeation chromatography, UV absorption spectra, fluorescence spectra, Fourier transform infrared spectroscopy, size distribution and zeta potential measurement, and transmission electron microscopy. Biocompatibility evaluation and cell imaging of TPE-PEI FONs were further explored. We demonstrated that such FONs showed intense fluorescence, spherical morphology and excellent biocompatibility, making them very suitable for cell imaging application.

关键词： Aggregation-induced emission Polyethylenimine Schiff base condensation Fluorescent organic nanoparticles Cell imaging.

Behaviors and interactions of strengthening and constraint for ductile Nbss matrix in Nb-Si based alloys

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Progress in Natural Science:materials International 2022年第2期32卷 215-225页

作者： Yu Wang Lina Jia Chengtong Ye Guangxin Sun Hu Zhang School of materials Science and Engineering Beihang University Research Center of Light-alloy materials Frontier Institute of Science and Technology Innovation Beihang University Ningbo Institute of Technology (NIT) Beihang University department of materials Science and Engineering National University of Singapore

The ductile matrix in composites could be strengthened by incorporating brittle inclusions,while the constraint effect for matrix would become more obvious and detrimental to material *** balance between strengthening and toughening was crucial to achieve excellent comprehensive mechanical *** the basis of microstructure of Nb-Si in situ composites,a unit rectangular cell containing elastic and isotropic Nb5Si3particles was modeled,the Niobium solid solution(Nbss) matrix according with the Ramberg-Osgood constitutive relation was recognized as *** Nb-Si based alloys,the effects of volume fractions of Nb5Si3reinforcements,stress states and interfacial characteristics on the stress-strain field,flow localization and damage evolution were investigated by the finite element method(FEM).Further,the normalized work of rupture(χ) was calculated quantitatively as a function of volume fractions of Nb5Si3phase as well as yield strength of Nbss *** results would contribute to acquire more fundamental understanding of the strengthening and constraint effects which were exerted by Nb5Si3reinforcements to ductile Nbssmatrix,also an instructive guidance for the optimum design of Nb-Si based alloys.

关键词： Nb-Si based Alloys Microstructure Fracture characteristics Matrix strengthening Plastic constraint Finite element method

Electrochemically stable lithium-ion and electron insulators(LEIs)for solid-state batteries

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Nano Research 2022年第2期15卷 1213-1220页

作者： Kai Pei So Yeon Kim Ju Li frontier Institute of Science and Technology Xi'an Jiaotong UniversityXi'an 710049China department of materials Science and Engineering and department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

Rechargeable solid-state Li metal batteries demand ordered flows of Li-ions and electrons in and out of solid structures,with repeated waxing and waning of Ubcc phase near contact interfaces which gives rise to various electro-chemo-mechanical *** have been approaches that adopt three-dimensional(3D)nanoporous architectures consisting of mixed ion-electron conductors(MIECs)to combat these ***,there has remained an issue of LiBcc nucleation at the interfaces between different solid components(e.g.,solid electrolyte/MlEC interface),which could undermine the interfacial bonding,thereby leading to the evolution of mechanical instability and the loss of ionic/electronic *** this regard,the present work shows that the Li-ion and electron insulators(LEIs)that are thermodynamically stable against LiBcc could combat such challenges by blocking transportation of charge carriers on the interfaces,analogous to dielectric layers in *** searched the ab initio database and have identified 48 crystalline compounds to be LEI candidates(46 experimentally reported compounds and 2 hypothetical compounds predicted to be stable)with a band gap greater than 3 eV and vanishing Li *** these compounds,those with good adhesion to solid electrolyte and mixed ion-electron conductor of interest,but are lithiophobic,are expected to be the most *** also extended the search to Na or K metal compatible alkali-ion and electron insulators,and identified some crystalline compounds with a property to resist corresponding alkali-ions and electrons.

关键词： electrochemical stability window stress fracture adhesion contact lithium metal anode