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International Journal of minerals,metallurgy and materials 2017年第11期24卷 1306-1320页

作者： Z.m.Sheggaf R.Ahmad m.b.A.Asmael A.m.m.Elaswad Department of manufacturing and Industrial Engineering Faculty of Mechanical and Manufacturing Engineering Universiti Tun Hussein Onn Malaysia Parit Raja86400 BatuPahat Johor Malaysia Department of mechanical Engineering Eastern Mediterranean University North Cyprus Gazimagsa TRNC Mersin 10 Turkey

The influence of praseodymium(Pr) content on the solidification characteristics, microstructure, and mechanical properties of ZRE1 magnesium(mg) cast alloy was investigated. The obtained solidification parameters showed that Pr strongly affected the solidification time, leading to refinement of the microstructure of the alloys. When the freezing time was reduced to approximately 52 s, the grain size decreased by 12%. mg_(12)Zn(Ce,Pr) was formed as a new phase upon the addition of Pr and was detected via X-ray diffraction analysis. The addition of Pr led to a substantial improvement in mechanical properties, which was attributed to the formation of intermetallic compounds; the ultimate tensile strength and yield strength increased by approximately 10% and 13%, respectively. Pr addition also refined the microstructure, and the hardness was recovered. The results herein demonstrate that the mechanical properties of mg alloys are strongly influenced by their microstructure characteristics, including the grain size, volume fraction, and distribution of intermetallic phases.

关键词： metal solidification microstructure mechanical properties magnesium alloys intermetallics

Application of experimental design in optimization of crude oil adsorption from saline waste water using raw bagasse

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Journal of Central South University 2014年第2期21卷 684-693页

作者： m.behnood b.Nasernejad m.Nikazar Department of Chemical Engineering Amirkabir University of Technology (Tehran Polytechnic)Mahshahr Campus Food Process Engineering and biotechnology Research Center Amirkabir University of Technology(Tehran Polytechnic)

Experimental design was applied in the optimization of crude oil adsorption from saline waste water using raw *** application of response surface methodology(RSm) was presented with temperature,salinity of water,pH,adsorbent dose,and initial oil content as factors.A quadratic model could be used to approximate the mathematical relationship of crude oil removal on the five significant independent *** values and experimental values are found to be in good agreement with R2 of 97.44%.The result of optimization shows that the maximum crude oil removal is equal to 67.38% under the optimal condition of temperature of 46.53 °C,salinity of 37.2 g/L,pH of 3,adsorbent dose of 9 g/L and initial oil content of 300×10-6.

关键词： brine crude oil adsorption raw bagasse experimental design

Nonlinear elastic constitutive relations of residually stressed composites with stiff curved fibres

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Applied mathematics and mechanics(English Edition) 2022年第10期43卷 1515-1530页

作者： m.H.b.m.Shariff J.merodio R.bustamante Department of mathematics Khalifa University of Science and TechnologyAbu Dhabi127788United Arab Emirates Departamento de matemática Aplicada a las TIC ETS de Ingeniería de Sistemas InformaticosUniversidad Politecnica de MadridMadrid28031Spain Departamento de Ingeniería mecánica Universidad de ChileBeauchef 851Santiago CentroSantiago8370448Chile

mechanical models of residually stressed fibre-reinforced solids,which do not resist bending,have been developed in the ***,in some residually stressed fibre-reinforced elastic solids,resistance to fibre bending is significant,and the mechanical behavior of such solids should be ***,in this paper,we model the mechanical aspect of residually stressed elastic solids with bending stiffness due to fibre curvature,which up to the authors’knowledge has not been mechanically modeled in the *** proposed constitutive equation involves a nonsymmetric stress and a couple-stress *** invariants are used in the constitutive equation,where each spectral invariant has an intelligible physical meaning,and hence they are useful in experiment and analysis.A prototype strain energy function is ***,we use this prototype to give results for some cylindrical boundary value problems.

关键词： fibre-reinforced solid residual stress bending stiffness spectral invariant second gradient finite elasticity

Influence of FCA Welding Process Parameters on Distortion of 409m Stainless Steel for Rail Coach building

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Journal of Iron and Steel Research International 2013年第1期20卷 71-78页

作者： m V Venkatesan N murugan b m Prasad A manickavasagam Department of mechanical Engineering Coimbatore Institute of TechnologyCoimbatore 641014TNIndia Integral Coach Factory Indian RailwaysChennai 600038TNIndia

The influence of flux cored arc welding （FCAW） process parameters such as welding current, travel speed, voltage and CO2 shielding gas flow rate on bowing distortion of 409m ferritic stainless steel sheets of 2 mm in thickness was discussed. The bowing distortions of the welded plates were measured using a simple device called profile tracer. An experimental regression equation was developed to predict the bowing distortion and with this equation, it is easy to select optimized process parameters to achieve minimum bowing distortion. It is revealed that the FCAW process parameters have significant influence on bead profile and the bowing distortion.

关键词： bowing distortion ferritic stainless steel flux cored arc welding statistical model rail coach distortion measurement

Estimate of fine sediment deposit dynamics over a gravel bar using photography analysis

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International Journal of Sediment Research 2013年第2期28卷 220-233页

作者： b.CAmENEN m.JODEAU m.JAbALLAH Irstea HHLY5 rue de la DouaCS 70077-69626 Villeurbanne cedexFrance DrResearch scientist EDF-LNHE 6 quai Watier78401 Chatou cedexFrance DrResearch scientist Irstea HHLY5 rue de la DouaCS 70077-69626 Villeurbanne cedexFrance PhD candidate

Three different methods to analyse fine sediment deposits on a gravel bar using pictures are presented in this paper.A manual digitization and deposits zone delineation are performed as well as two different automated *** three methods are applied on aerial pictures taken in 2006 by a drone from a height around 150 m above the study site. Two other sets of pictures taken in 2010 are also studied:the first set was obtained from the left side bank of the river at approximately 15m above the gravel bar whereas the second one was taken from a helicopter flying 600 m above the *** methods were used to estimate the surface of fine sediment deposits before and after flushing events. They yield similar results even if the first automated procedure is able to capture smaller patches of fine *** total surface of fine sediment deposits seems to be similar before and after a flushing event,but the distribution appears quite *** a flushing event,a significant amount of fine sediment deposits are mixed with coarser *** the flushing event,one can observe more large fine sediment deposits located on the downstream part of the secondary channel and at the channel *** of the small fine sediment deposit patches were washed out. A short discussion is provided on the possible dynamics of fine sediment deposits over the gravel bar.

关键词： Fine sediment deposits Photo analysis Automated procedure Flushing event

bendable tube-shaped supercapacitor based on reduced graphene oxide and Prussian blue coated carbon fiber yarns for energy storage

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Journal of Energy Chemistry 2018年第3期27卷 866-873页

作者： mohd.Khalid Ana m.b.Honorato Department of macromolecular Science and Engineering Case Western Reserve University

Carbon fiber yarns（CFY） are promising as a new type of flexible building blocks for the construction of flexible architectures for the energy storage applications. The main hurdle with CFY is how to make them high energy and power capable by using economically and environmentally viable materials. Here,we report reduced graphene oxide（r GO） and Prussian blue（Pb） coated CFY, derived from a facile electrochemical process at room temperature for supercapacitor electrodes. The Pb coated CFY and r GO coated CFY electrodes exhibit the excellent gravimetric capacitance of 339 F/g and 160.2 F/g, respectively, in aqueous KCl electrolyte in three-electrode cell configuration. When we coupled these electrodes inside the flexible plastic tube and separated by the electrolyte wet filter paper in order to construct flexible architecture, the resulting device delivers excellent specific energy of 52.1 Wh/kg and 26.5 Wh/kg with offering specific power of 3100 W/kg and 14400 W/kg respectively, under a wide operating potential of1.8 V with excellent rate capability. The device shows high tolerance towards bending, and retained its efficiency to the capacitance after being bent at an angle of 360° for 200 bending cycles.

关键词： Carbon fiber yarns bendable supercapacitor Energy density Power density

Transient transport processes in deformable porous media

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Chinese Physics b 2011年第11期20卷 167-175页

作者： Cs.mészáros A.bálint Szent István University Department of Physics and Process Control Szent István University Department of Chemistry and Biochemistry

The basic partial differential equations relevant for convection-diffusion and convection-diffusion-wave phenomena arc presented and solved analytically by using the mAPLE symbolic computer algebra system. The possible general nonlinear character of the constitutive equation of the convection-discussion process is replaced by a direct posteriori stochastic refinement of its solution represented for Dirichlet-type boundary conditions. A thermodynamic analysis is performed for connecting the relaxation time constants and Jacobi-determinants of deformations at transient transport processes. Finally, a new procedure for general description of coupled transport processes on the basis of the formalism originally developed for convection-free phenomena is presented by matrix analysis methods in the Fourier space.

关键词： convection binary mixtures relaxation time matrix polynomials

A new apparatus to establish the spontaneous combustion propensity of coals and coal-shales

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International Journal of mining Science and Technology 2018年第4期28卷 643-649页

作者： m.Onifade b.Genc A.Carpede School of mining Engineering University of the Witwatersrand

Coal and coal-shale both tend to undergo spontaneous combustion under favourable atmospheric conditions. The Wits-Ehac index has been developed in South Africa since the late 1980's to test the spontaneous combustion liability of coal. However, in some cases, the Wits-Ehac index fails to produce tangible results when testing coal-shales. To overcome this problem, a new apparatus has been developed to test carbonaceous materials such as coal and coal-shale under chemical reactions with oxygen and an index has been obtained. This index is called the Wits-CT index. The equipment emulates the influence of oxygen adsorption on carbonaceous material for a period of 24 h without a heating *** Wits-CT index uses the total carbon content of the sample and the temperature variations obtained from the samples during reaction with oxygen to predict the spontaneous combustion liability. Eighteen samples have been analyzed using both indices and the results are in-line. It was found that coals and coal-shales with higher values of the Wits-CT index are more liable to spontaneous *** research on different coal-shales is underway in order to establish an extensive database for coal and coal-shales, together with known incidences of self-heating.

关键词： Coal Coal-shale Spontaneous combustion Wits-Ehac index Wits-CT index

Chemical forms and extractability of iron in sediments of three contrasting lakes of China and UK

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Journal of Environmental Sciences 2003年第6期15卷 728-733页

作者： Gibson C.E.,Stewart b.m. Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Department of Agricultural and Environmental Science Queen's University belfast Shenyang 110016 China Newforge Lane belfast bT9 5PX UK

Iron is a limiting factor for the eutrophication of lakes, especially those lakes that are enriched with phosphorus. Extractability of iron in sediments of West Lake and Taihu Lake in China and Lower Lough Erne in Northern Ireland of UK was comparatively investigated on the basis of analysing chemical forms of iron using different extractants. It was shown that extractable iron in sediments of the lakes was greatly different using various extractants. Reactive iron or easily released iron such as “active" iron oxides, total free iron oxide and water-soluble iron was not high, only accounting for 0.01%—0.15% of total iron. The efficiency of the extractants for exchangeable iron was decreased in the sequence 0.1 mol/L HCl DTPA+TEA mixed solution > 1 mol/L NH 4OAc > 0.5 mol/L mgCl 2 = 0.5 mol/L CaCl 2. It seems that the complexion of iron by organic matter was not strong because the concentration of organically bound iron was significantly lower than the concentration it was forecasted. Extractable iron is not entirely consistent with or dependent on total iron in lake sediments. To a certain extent, phosphate can inhibit the release of iron in sediments of the lakes. The selection of extractants is thus the first key step to evaluate bioavailability of iron in lake sediments.

关键词： iron chemical form extractability lake sediment eutrophication

Environment friendly protocol for the synthesis of nitriles from aldehydes

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Chinese Chemical Letters 2010年第9期21卷 1025-1028页

作者： m.b.madhusudana Reddy m.A.Pasha Department of Studies in Chemistry Central College CampusBangalore University

A rapid and eco-friendly one-pot protocol for the synthesis of nitriles has been developed by treating various araldehydes bearing electron withdrawing as well as electron donating groups with hydroxylamine hydrochloride in the presence of non-toxic,non-corrosive and reusable zinc oxide（ZnO） as the catalyst under solvent-free microwave *** present approach offers the advantages of a clean reaction,simple methodology,employing readily available catalyst,short reaction duration（〈1 min）,high selectivity;and high yield（90-98%）.

关键词： Aldehydes Nitriles Solvent-free microwave irradiation benign procedure