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Effects of slag fineness on durability of mortars

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2007年第11期8卷 1725-1730页

作者： TOPu lker Bekir Blr Turhan Department of Civil Engineering Eski■ehir Osmangazi university Eski■ehir 26480 Turkey

In recent years, the usages of by-products and wastes in industry have become more important. The importance of the sustainable development is also of increasing. The utilizations of wastes, as mineral admixture or fine aggregate, reduce the consumption of the natural resources and improve the durability of concrete. In this study, the effect of the fineness on the high temperature and sulphate resistances of concrete mortar specimens, produced with ground granulated blast-furnace slag (GBFS) replacing cement, is investigated. The compressive and flexural strength test results for all series related to durability effects, exposing temperature and solutions, exposure times for these durability effects, slag content and fineness are discussed. Conse- quently, the optimum slag contents are determined for producing the sulphate and high temperature resistant mortars.

关键词： Cement Fineness Ground slag High temperature effect Sulphate attack Sustainable development

Force and impulse multi-sensor based on flexible gate dielectric field effect transistor

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 214-220页

作者： Chao Tan Junling lü Chunchi Zhang Dong liang lei Yang Zegao Wang College of Materials Science and Engineering Sichuan UniversityChengdu 610065China The 54th research Institute of China Electronics Technology Group Corporation Shijiazhuang 050081China

Nowadays,force sensors play an important role in industrial production,electronic information,medical health,and many other ***-dimensional material-based filed effect transistor(2D-FET)sensors are competitive with nano-level size,lower power consumption,and accurate ***,few of them has the capability of impulse detection which is a path function,expressing the cumulative effect of the force on the particle over a period of *** we fabricated the flexible polymethyl methacrylate(PMMA)gate dielectric MoS_(2)-FET for force and impulse sensor *** systematically investigated the responses of the sensor to constant force and varying forces,and achieved the conversion factors of the drain current signals(I_(ds))to the detected impulse(I).The applied force was detected and recorded by I_(ds)with a low power consumption of~30 *** sensitivity of the device can reach~8000%and the 4×1 sensor array is able to detect and locate the normal force applied on ***,there was almost no performance loss for the device as left in the air for two months.

关键词： flexible gate dielectric transistor force sensor impulse sensor force sensor array

Application of reactive Ion Etching to the Fabrication of Microstructure on Mo/Si Multilayer

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Chinese Physics letters 1999年第9期16卷 665-666页

作者： lE Zi-chun l.Dreeskornfeld S.rahn r.Segler u.Kleineberg u.Heinzmann Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012 Fakultät für Physik Universität BielefeldUniversitatsstraβe 25D-33615 BielefeldGermany

Mo/Si muitilayer mirrors(30 periods,doublelayer thickness 7nm)with the AZ-PF514 resist pattern whose smallest lines and spaces structure was 0.5pm were etched by reactive ion etching(rIE)in a fluorinated *** etch rate,selectivity and etch profile were investigated as a function of the gas mixture,pressure,and plasma rf *** groove depth and the etch proHle were investigated by an atomic force microscope before rIE,after rIE and after resist removal.

关键词： Mo/Si smallest selectivity

Oxidation behavior and microstructural evolution of FeCoNiTiCu five-element high-entropy alloy nanoparticles

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Journal of Materials Science & Technology 2024年第10期177卷 133-141页

作者： H.Bai r.Su r.Z.Zhao C.l.Hu l.Z.Ji Y.J.liao Y.N.Zhang Y.x.li x.F.Zhang Key laboratory for Anisotropy and Texture of Materials(MOE) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China Institute of Advanced Magnetic Materials College of Materials and Environmental EngineeringHangzhou Dianzi UniversityHangzhou310012China

High-entropy alloys(HEAs)have attracted extensive attention ascribed to their unique physical and chemical properties induced by the cocktail ***,their oxidation behaviors,in particular at nanoscale,are still lack because of multi-element complexity,which could also be completely differ-ent from the bulk *** this work,we synthesized FeCoNiTiCu five-element HEA nanopar-ticles(NPs)with uniform elemental distribution by arc-discharging approach,and further investigated their oxidation behaviors at 250 ℃,and 350 ℃.The morphology,structure and element distribution of NPs were analyzed by transmission electron microscopy(TEM),energy dispersive spectroscopy(EDS)and electron energy loss spectroscopy(EElS).The surface oxidation in FeCoNiTiCu NPs during the high-temperature process can induce nanoscale pores at core/shell interfaces by Kirkendall effect,and even the eventual coalescence into a single ***,the oxidation states of NPs with diameters(d)varying from 60 to 350 nm were analyzed in detail,revealing two typical configurations:hollow(dlk-shell structures(d>150 nm).The experimental results were complemented by first-principles calculations to investigate the diffusion behaviors of five elements,evidencing that the surface oxidation strongly alters the surface segregation preferences:(1)in the initial stage,Cu and Ni appear to prefer segregating on the surface,while Co,Ti and Fe tend to stay in the bulk;(2)in the oxidation process,Cu prefers to stay in the center,while Ti segregates to the surface ascribed to the reduced po-tential *** study gives new insights into oxidation of nanoscale HEA,and also provides a way for fabrication of high-entropy oxides with controllable architectures.

关键词： High-entropy alloy Nanoparticles Oxidation Kirkendall effect Exchange bias effect

Temperature dependence of pressure sensitive flow in bulk metallic glass composites

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Journal of Materials Science & Technology 2024年第14期181卷 165-175页

作者： Priyanka Saini Yakai Zhao Biao li long Zhang u.ramamurty r.l.Narayan Department of Materials Science and Engineering Indian Institute of TechnologyDelhi 110016India School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Republic of Singapore Institute of Materials research and Engineering Agency for ScienceTechnology and Research138634Republic of Singapore Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The constraint factor,C,defined as hardness,H,to the yield strength,σ_(y),ratio,is an indirect measure of the pressure sensitivity in *** investigations determined that while C is less than 3 for crystalline materials,and remains invariant with change in temperature,it is greater than 3 for bulk metallic glasses(BMGs)and increases with increasing temperature,below their glass transition temper-ature,T_(g).In this study,the variations in C for two BMG composites(BMGCs),which have an amorphous matrix and in situ precipitated crystallineβ-Ti dendrites,which in one case transforms under stress toα”-Ti and deforms by slip in the other,as a function of temperature are examined and compared with that of a *** this purpose,instrumented indentation tests,with a Berkovich tip,and uniaxial com-pression tests were performed to measure the H andσ_(y),respectively,on all alloys and their constituents at temperatures in the range of 0.48 T_(g) and 0.75 T_(g).σ_(y) and H of the BMGC with transforming dendrites(BMGC-T)increase and remain invariant with increasing temperature,***,in BMG and the BMGC with non-transforming dendrites(BMGC–NT),the same properties decrease with increas-ing ***-T has the highest C of∼4.93 whereas that of BMGC–NT and BMG are∼3.72 and∼3.28,respectively,at 0.48 T_(g).With increasing temperature,C of the BMG and BMGC–NT increases with temperature,but that of the BMGC-T *** values of C and their variations as a function of temperature were explained by studying the variation of pressure sensitivity of the amorphous phase and concluding that the plastic flow in BMGCs under constrained conditions,such as indentation,is con-trolled by the flow resistance of the amorphous matrix whereas that in uniaxial compression,which is only partially constrained,is controlled by plasticity in both the dendrites and matrix.

关键词： Bulk metallic glass composites Hardness Pressure sensitivity Martensitic transformation

Improved unlike-Particle Collision Operator for delta-f Drift-Kinetic Particle Simulations

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Communications in Computational Physics 2011年第2期9卷 231-239页

作者： r.A.Kolesnikov W.x.Wang F.l.Hinton los Alamos National laboratory Los AlamosNM 87544USA Plasma Physics laboratory P.O.Box 451PrincetonNJ 08543USA Center for Astrophysics&Space Science University of CaliforniaSan DiegoLa JollaCA 92093USA

Plasmas in modern tokamak experiments contain a significant fraction of impurity ion species in addition to main deuterium background.A new unlike-particle collision operator forδf particle simulation has been developed to study the nonlocal effects of impurities due to finite ion orbits on neoclassical transport in toroidal plasmas.A new algorithm for simulation of cross-collisions between different ion species includes test-particle and conserving field-particle *** improved field-particle operator is designed to exactly enforce conservation of number,momentum and energy.

关键词： Drift-kinetics magnetized plasmas

luminescence investigation of Dy2O2S and Dy2O2SO4 obtained by thermal decomposition of sulfate hydrate

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Journal of rare Earths 2016年第8期34卷 814-819页

作者： r.V.rodngues l.Marciniak l.u.Khan J.r.Matos H.F.Brito W.Strek Institute of Chemistry University of Sao Paulo Butanta 748 26077 Sao Paulo Brasil Institute of low Temperature and Structure research University of Wroctaw Oko1na 250-422 Wroclaw Poland

The yellow emitting dysprosium oxysulfide （Dy2O2S） and dysprosium oxysulfate （Dy202SO4） compounds were prepared from the thermal decomposition of hydrated dysprosium sulphate. The materials were characterized by using thermogravimetry （TG/DTG）, x-ray powder diffraction （xrD）, Fourier transform infrared （FTIr） and raman spectroscopies. The thermal stability temperatures at around 1151 and 1313 K were determined for the Dy202S and Dy202SO4 materials, respectively. The photolumines- cence properties of the dysprosium oxysulfide were investigated, showing narrow emission bands assigned to the 4F9/2----＊6HJ intracon- figurational transitions of the Dy3＋ ion. The yellow emission color of this phosphor suggests that the Dy202S is a promising material for applications in lEDs.

关键词： Dy202S/Dy202SO4 sulfate thermal decomposition luminescence rare earths

Plastic deformation of a Zr-based bulk metallic glass fabricated by selective laser melting

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Journal of Materials Science & Technology 2021年第1期60卷 139-146页

作者： l.Deng K.Kosiba r.limbach l.Wondraczek u.Kühn S.Pauly IFW Dresden Institute for Complex MaterialsHelmholtzstraße 20D-01069DresdenGermany Otto Schott Institute of Materials research University of JenaFraunhoferstraße 6D-07743JenaGermany university of Applied Sciences Aschaffenburg Würzburger Straße 45D-63743AschaffenburgGermany

Fully amorphous Zr_(52.5)Cu_(17.9)Ni_(14.6)Al_(10)Ti_(5) bulk metallic glass(BMG) samples with a relative density exceeding 98% were fabricated via selective laser melting(SlM).High fracture stresses of around1700 MPa and a reproducible plastic strain of about 0.5% were obtained for cylindrical SlM *** analysis of the observed serrations during compressive loading implies that the shear-band dynamics in the additively manufactured samples distinctly differ from those of the as-cast *** phenomenon appears to originate from the presence of uniformly dispersed spherical pores as well as from the more pronounced heterogeneity of the glass itself as revealed by instrumented *** these heterogeneities,the shear bands are straight and form in the plane of maximum shear *** manufacturing,hence,might not only allow for producing large BMG samples with complex geometries but also for manipulating their deformation behaviour through tailoring porosity and structural heterogeneity.

关键词： Powder bed fusion Selective laser melting Bulk metallic glass Serrated flow Heterogeneity

Wear of semi-solid rheocast SiC_p/Al metal matrix composites

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中国有色金属学会会刊：英文版 2010年第S3期20卷 852-856页

作者： u.A.CurlE l.IVANCHEV Materials Science and Manufacturing Council for Scientific and Industrial Research(South Africa)

rheocasting of plates in Al alloy 359 reinforced with SiC at 11%,27% and 50%(volume fractions) exhibits the capability of the council for scientific and industrial research-rheocasting system(CSIr-rCS) in rheo-processing and high pressure die casting of SiC metal matrix *** metal matrix consisting of nearly spherical proeutectic α(Al) globules was *** of fibrous eutectic silicon took place upon heat treatment of the as-cast metal matrix composites(MMCs).Hardness increases as the volume fractions of SiC *** rates of the MMCs in the F and T6 heat treatment conditions were assessed with a metallographic preparation *** is found that the 11% SiC MMC wear rate is higher on SiC abrasives compared with the 50% SiC MMC wear rate due to wear of the aluminum *** trend is reversed on diamond abrasives due to pull-out of the irregular shaped composite *** 50% SiC MMC suffers from composite particle fracture porosity after high pressure die casting(HPDC).

关键词： CSIr-rCS HPDC SiC F condition T6 condition wear rate hardness porosity