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Multifunctional A356 alloy/PKsAnp composites:Microstructure and mechanical properties

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Defence Technology（防务技术） 2020年第3期16卷 731-736页

作者： V.s.Aigbodion I.c.Ezema Department of Metallurgical and Materials Engineering University of NigeriaNsukkaNigeria

Mechanical properties and microstructure of multifunctional composites produced with palm kernel shell ash nano particle(PKsAnp)-A356 alloy composites.w.s *** composites.w.re produced using Double layer feeding stir casting method(DLF-scM) by adding 1 wt%-4 wt.% *** microstructure,density,electrical and mechanical properties.w.re *** results shows that there was a uniform distribution of the PKsAnp in A356 *** mismatch at the interface between the PKsAnp and A356 alloy was 4.26%.Improvement of 30.47%,41.91%,49.52%,40.90% and 65.09% were obtained for hardness values,tensile,yield strength,%elongation and impact energy at 4 wt% *** work has established that the developed composites can be used for multifunctional applications.w.ere combination of toughness and strength is vital.

关键词： PKsAnp A356 alloy Microstructure Electrical and mechanical properties

Fatigue Behaviour of Naval steel Under seawater Environmental and Variable Loading conditions

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Journal of Iron and steel Research International 2011年第5期18卷 64-69页

作者： c Gheorghies L Palaghian s Baicean M Buciumeanu s ciortan Department of Physics University "Dunarea de Jos" of Galati Department ofMechanical Engineering University "Dunarea de Jos" of Galati

The way to characterize the behaviour of a naval steel grade E36 subjected to the corrosive fatigue process is investigated. The tests.w.re carried out by bending fatigue of plate specimens.w.th thickness of 10 mm in the corrosive environment consisting of an aqueous solution of 3.5% of Nacl which is similar to seawater. Experimental results show that the principal mechanism of degradation of the superficial layer is based on the pit evolution,evidenced by electrochemical,micro and macro structural timely changes such as evolution of electrode potential,evolution of current density,polarization resistance,anodic and cathodic parameters,and dislocation density evolution.

关键词： naval steel fatigue pitting corrosion structure

Influence of Fe Addition on Products of self-Propagating High-Temperature synthesis Reaction in 3Ti-si-2c system

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稀有金属材料与工程 2009年第A3期38卷 113-118页

作者： Guan Q L wang H Y Li s L si w P Jiang Q c Key Laboratory of Automobile Materials of Ministry of Education Jilin University Changchun 130025 China

Influence of Fe addition on products of self-propagating high-temperature synthesis (sHs) reaction in 3Ti-si-2c system was investigated in the present study. without Fe addition, Ti5si3 and Tic are the dominant phases along with a small amount of Ti3sic2 phase and unreacted c left in the final products. As Fe content ranges from 10% to 30%, the products consist of Tic, Ti5si3, Fe2Ti and unreacted c, but no trace of Ti3sic2 phase is detected. Furthermore, the amounts of both Fe2Ti and c phases increase with Fe content increasing. Addition of Fe has a great effect on the reaction route and significantly restrains the formation of Ti3sic2 during the combustion synthesis process, and therefore, the sHs is not an effective fabrication technique to synthesize the ternary Ti3sic2 ceramic in either 3Ti-si-2c or Fe-3Ti-si-2c system. Besides, without Fe addition, Ti5si3 presents as the coarse irregular appearance with an obviously sintered morphology. In contrast, the shape of Ti5si3 exhibits more and more spherical (cobblestone-like) and the surface becomes increasingly smooth, because the amount of liquids formed during the sHs reaction increases.w.th the increase of Fe content. On the other hand, with Fe content increasing from 0 to 30 wt.%, the particulate size of Tic decreases from more than 5 μm to 1 μm or less, mainly due to the fact that the combustion temperature decreases.w.th the increase of Fe content in the preforms.

关键词：复合材料铁含量燃烧过程物理性能

strong enhancement on dye photocatalytic degradation by ball-milled TiO2:A study of cationic and anionic dyes

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Journal of Materials science & Technology 2017年第8期33卷 856-863页

作者： Z.Jia L.B.T.La w.c.Zhang s.X.Liang B.Jiang s.K.Xie D.Habibi L.c.Zhang school of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA 6027Australia Environmental Protection Administration of fi'an cith Ji'an 343000China school of Mechanical and chemical Engineering The University of Western AustraliaPerchWA 6009Australia school of Materials science and Engineering University of Science and TechnologyBeijing 100083China school of Mechanical&Electrical Engineering finggangshan Universityfl'an 343000China

TiO2 particles.w.th desirable properties.w.re produced by undergoing specific durations of ball *** of the TiO2 particles before and after ball milling were investigated via X-ray diffraction（XRD）, Brunauer-Emmett-Teller（BET）, particle size analysis, zeta potential, and scanning electron microscope（sEM）. The equilibrium adsorption data were well fitted to Langmuir, Freundlich, and Dubinin-Radushkevich（D-R） isotherms. compared to the as-received TiO2（mean particle size d150= 0.78μm, specific surface area = 88.17 m^2g-1, pore volume = 0.41 cm^3g-1）, the 60 min ballmilled TiO2（d50= 0.55 μm, specific surface area = 99.48 m2g-1, pore volume = 0.48 cm3g-1） enhanced the adsorption quantity of congo red and methylene blue from 10.4 mg g-1to 13.6 mg g-1, and from17.0 mg g-1to 22.2 mg g-1, respectively; and also improved the kinetic rates from k = 0.1325 to 0.2193, and k = 0.0944 to 0.1553, respectively. Dye adsorption and degradation efficiency of congo red was enhanced in acidic p H range（2–5.14）, and methylene blue was enhanced in alkaline p H range（7.58–12）.

关键词： Ball-milled TiO2 congo red Methylene blue Equilibrium adsorption Photocatalysis

Highly efficient synthesis of β-amino esters via Mannich-type reaction under solvent-free conditions using Zncl_2 catalyst

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chinese chemical Letters 2009年第4期20卷 407-410页

作者： Albert s.c.chan school of Pharmaceutical science Sun Yat-Sen University

β-Amino esters.w.re synthesized via Zncl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid de... 详细信息

关键词： β-Amino esters Aspartic acid derivativates Mannich-type reaction solvent-free Krapcho decarboxylation reaction Zinc chloride

Natural vibration of cantilever porous twisted plate with variable thickness in different directions

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Defence Technology（防务技术） 2023年第9期27卷 200-216页

作者： Y.X.Hao Y.Y.Liu w.Zhang L.T.Liu K.c.sun s.w.Yang college of Mechanical Engineering Beijing Information Science and Technology UniversityBeijing100192PR China college of Mechanical Engineering Beijing University of TechnologyBeijing100124PR China

In this paper,the blade is assumed to be a rotating variable thickness cantilever twisted plate structure,and the natural vibrations of variable thickness cantilever twisted plate made of metal porous material are *** is assumed that the thickness of the plate changes along spanwise direction and chordwise direction,respectively,and it changes in both *** classical thin shell theory,the first and second fundamental forms of surface and von Karman geometric relationship are employed to derive the total potential energy and kinetic energy of the cantilever twisted plate,in which the centrifugal force potential due to high rotational speed is ***,according to the Rayleigh-Ritz procedure and applying the polynomial functions.w.ich satisfy the cantilever boundary conditions,the dynamic system expressed by equations of motion is reduced to an eigenvalue *** numerical simulation,the frequency curves and the mode shapes of the twisted plate can be obtained to reveal the internal connection between natural vibration and the parameters.A series of comparison studies are performed to verify the accuracy of the present formulation and calculations,in which compared data come from experimental,finite element method and theoretical calculation,*** influence of pre-twist angle,three different forms of thickness taper ratio and rotational speed on natural vibration,mode exchange and frequency veering phenomenon of the system is discussed in *** addition,the approach proposed here can efficiently extract analytical expressions of mode functions for rotating variable thickness cantilever twisted plate structures.

关键词： Porous cantilever twisted plate Variable thickness Natural vibration Frequency veering Mode exchange

constraints on the nuclear symmetry energy and its density slope from theαdecay process

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chinese Physics c 2018年第6期42卷 79-87页

作者： w.M.seif A.s.Hashem cairo University Faculty of ScienceDepartment of Physics12613 GizaEgypt

we study the impact of the nuclear symmetry energy and its density dependence on the α-decay *** the framework of the preformed cluster model and the energy density formalism, we use different parameterizations of the skyrme energy density functionals that yield different equations of state（EOs）. Each EOs is characterized by a particular symmetryenergy coefficient（asym） and a corresponding density-slope parameter L. The stepwise trends of the neutron（proton） skin thickness of the involved nuclei with both asym and L do not clarify the oscillating behaviors of the α-decay half-life Tα with these quantities. we find that the change of the skin thickness after α-decay satisfactorily explains these behaviors. The presented results provide constraints on asym centered around an optimum value asym = 32 MeV, and on L between 41 and 57 MeV. These values of asym and L, which indicate larger reduction of the proton-skin thickness and less increase in the neutron-skin thickness after an α-decay,yield a minimum calculated half-life with the same extracted value of the α-preformation factor inside the parent nucleus.

关键词： alpha decay symmetry energy neutron-skin thickness proton-skin

Osteopontin is an important mediator of alcoholic liver disease via hepatic stellate cell activation

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world Journal of Gastroenterology 2014年第36期20卷 13088-13104页

作者： Devanshi seth Alastair Duly Paul c Kuo Geoffrey w Mccaughan Paul s Haber Drug Health services Royal Prince Alfred Hospital Camperdown NSW 2050 Australia Garvan Institute Darlinghurst NSW 2010 Australia central clinical school of Medicine the University of Sydney Sydney NSW 2050 Australia Department of surgery Loyola University Medica Centre Maywood IL 60153 United States Aw Morrow Gastroenterology and Liver centre RPAH Camperdown NSW 2050 Australia

AIM: To investigate over-expression of Osteopontin (OPN) pathway expression and mechanisms of action in human alcoholic liver disease (ALD), in vivo and in vitro acute alcohol models.

关键词： Hepatic stellate cells Liver cirrhosis Plasmin steatosis Fibrogenesis Transforming growth factor β Osteopontin isoform

B3 0749+460A: A New Repeat “changing-look” Active Galactic Nucleus Associated with X-Ray spectral slope Variations

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Research in Astronomy and Astrophysics 2022年第1期22卷 114-125页

作者： J.wang w.K.Zheng D.w.Xu T.G.Brink A.V.Filippenko c.Gao s.s.sun J.Y.wei Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key Laboratory of space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Department of Astronomy University of CaliforniaBerkeleyCA 94720-3411USA school of Astronomy and space science University of Chinese Academy of SciencesBeijing 100049China Miller Institute for Basic Research in science University of CaliforniaBerkeleyCA 94720USA

Here we report an identification of B3 0749+460 A as a new double-peaked local "changing-look" active galactic nucleus(cL-AGN) in terms of our multi-epoch spectroscopic analysis. By comparing our new spectra taken in 2021 with the ones taken by the sloan Digital sky survey in 2004, BOss in 2013 and Ma NGA in 2016, we reveal type transitions of seyfert(sy) 1.9 → sy1.8 → sy1.9. In the transitions, the classical broad Hα emission fades away after 2013 and disappears in our 2021 spectrum, although the absence of broad Hβ can be traced back to at least 2016. A follow-up observation in X-rays by the swift/XRT reveals that(1) the X-ray emission level gradually decreased since 2005;and(2)the X-ray spectrum is soft in the optical "turn-off" state and hard in the "turn-on" state. we argue that the disappearance of the classical broad Hα emission can be likely explained by the disk-wind broad-line-region model, in which the cL phenomenon is sensitive to luminosity in individual AGNs.

关键词： galaxies:seyfert galaxies:nuclei (galaxies:)quasars:emission lines (galaxies:)quasars:individual(B30749+460A) X-rays:galaxies