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Copper solvent extraction from alkaline cyanide solution with guanidine extractant LIX 7950

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Transactions of Nonferrous Metals Society of China 2010年第6期20卷 1136-1140页

作者： f.XIE D.b.DREISINGER Department of Materials Engineering University of British Columbia

The use of the guanidine extractant LIX 7950 extracting copper and cyanide from alkaline cyanide solution was *** extraction of copper and cyanide under different initial copper and extractant concentrations was examined and the stoichiometric extraction constant of Cu(CN)32- with LIX 7950 was *** the distribution coefficient and the stoichiometric extraction constant of Cu(CN)3 2-with LIX 7950 decrease when the temperature is varied from 25℃to 45℃, indicating the extraction process is *** calculated enthalpy change of the reaction(-HΘ)is about-190 kJ/*** copper extraction isotherms under different molar ratios of cyanide to copper are *** preferential extraction of Cu(CN)32- over Cu(CN)4 3-and CN -has been confirmed and a high cyanide-to-copper molar ratio tends to suppress copper loading. The loaded copper and cyanide can be stripped efficiently by the moderately strong NaOH solutions(0.5-1.0 mol/L)and the presence of NaCN in the stripping solution facilitates copper stripping.

关键词： copper cyanide solvent extraction guanidine

Application of clan member signal method in structural damage detection

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Earthquake Engineering and Engineering Vibration 2007年第1期6卷 29-34页

作者：郭迅 b.f.Spencer 卢书楠 Institute of Engineering Mechanics China Earthquake Administration Dept of Civil and Environmental Engineering University of Illinois at Urbana-Champaign

It is well known that in most cases, a reference is necessary for structural health diagnosis, and it is very difficult to obtain such a reference for a given structure. In this paper, a clan member signal method （CMSM） is proposed for use in structures consisting of groups （or clans） that have the same geometry, i.e., the same cross section and length, and identical boundary conditions. It is expected that signals measured on any undamaged member in a clan after an event could be used as a reference for any other members in the clan. To verify the applicability of the proposed method, a steel truss model is tested and the results show that the CMSM is very effective in detecting local damage in structures composed of identical slender members.

关键词： damage detection health monitoring vibration based clan member signal method local damage

Laser induced photo-detachment of O2 in DC discharge

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Plasma Science and Technology 2018年第7期20卷 98-105页

作者： j r legorreta j l patiNo f b yousif Centro de Investigacion en Ciencias Universidad Autonoma del Estado de Morelos.Av.UniversidadNo.1001 Col.Chamilpa Cuemavaca MorelosMexico

Determination of the negative ion number density of O2 and O in a DC discharge of oxygen plasma was made employing Langmuir probe in conjunction with eclipse laser photo- detachment technique. The temporal evolution of the extra electrons resulting from the photo- detachment of O2- and O- were used to evaluate the negative ion number density. The ratio of O2 number density to O varied from 0.03 to 0.22. Number density of both O~ and O increased with increasing power and decreased as the pressure was increased. Electron number density was evaluated from the electron energy distribution function （EEDf） using the I-V recorded characteristic curves. Electron temperature between 2 and 2.7 eV were obtained. Influence of the 02（al△g） metastable state is discussed.

关键词： electronegative plasma electron temperature Langmuir probe negative ion number density

Peristaltic flow with convective mass condition and thermal radiation

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Journal of Central South University 2015年第6期22卷 2369-2375页

作者： f.M.Abbasi T.Hayat b.Ahmad b.Chen Department of Mathematics Comsats Institute of Information Technology Department of Mathematics Quaid-I-Azam University 45320 Islamabad 44000 Pakistan Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Faculty of ScienceKing Abdulaziz University State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University

The primary objective of present investigation is to introduce the novel aspects of convective mass condition and thermal radiation in the peristaltic transport of fluid. Magnetohydrodynamic(MHD) fluid was considered in a symmetric channel. Heat and mass transfer characteristics were analyzed in the presence of Soret and Dufour effects, and the results were presented via two forms of thermal radiation. The temperature, concentration and pressure rise per wavelength were examined. It is observed that the velocity slip and magnetic field parameters have opposite effects on the pressure rise per wavelength. Temperature of fluid is a decreasing function of the radiation parameter. further, the temperature of fluid decreases by increasing the heat transfer biot number. It is notified that the heat transfer rate at the wall is a decreasing function of radiation parameter.

关键词： convective mass condition thermal radiation magnetohydrodynamic (MHD) fluid

Interfacial effects in electromagnetic coupling within piezoelectric phononic crystals

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Acta Mechanica Sinica 2009年第1期25卷 95-99页

作者： f. J. Sabina A.b.Movchan Instituto de Investigaciones en Matematicas Aplicadas yen Sistemas Universidad Nacional Autónoma de México Department of Mathematical Sciences University of Liverpool

In this paper, we discuss waves in piezoelectric periodic composite, with the emphasis on the connection between the electromechanical coupling and the effects of dispersion of bloch-floquet waves. A particular attention is given to structures containing interfaces between dissimilar media and localization of the electrical fields near such interfaces.

关键词： Piezoelectric periodic composites Interfaces Dispersion of bloch-floquet waves

Electron Acceleration by Microwave Radiation Inside a Rectangular Waveguide

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Plasma Science and Technology 2011年第3期13卷 357-361页

作者： b. f. MOHAMED A.M. GOUDA Plasma Physics Department N.R.C. Atomic Energy Authority Cairo Egypt

Electron dynamics in the fields associated with a transverse magnetic （TM） wave propagating inside a rectangular waveguide is analytically studied. The relativistic momentum and energy equations for an electron are solved, which was injected initially along the propagation direction of the microwave. Expressions of the acceleration gradient and deflection angle are obtained. In principle, it is shown that the electron can be accelerated in this condition and there is no deflection when the electron is injected from the centre of the waveguide front. However, it is found that the acceleration gradient and deflection angle depend strongly on the parameters of the microwave （intensity, frequency, etc.） and the dimensions of the waveguide.

关键词： waveguide electron acceleration polarized microwave

Synthesis and characterization of CaAl_xO_y:Eu^(2+) phosphors prepared using solution-combustion method

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Journal of Rare Earths 2010年第S1期28卷 272-276页

作者： f.b.Dejene D.b.bem H.C.Swart Department of Physics University of the Free State(Qwaqwa Campus)Private Bag X13Phuthaditjhaba9866South Africa Department of Physics University of the Free StateP.O.Box 339Bloemfontein9300South Africa

Europium-doped calcium aluminate(CaAlxOy:Eu2+) phosphors were obtained at low temperatures(500 oC) by the solution-combustion of corresponding metal nitrate-urea solution *** particle size and morphology and the structural and luminescent properties of the as-synthesized phosphors were examined by means of scanning electron microscopy(SEM),X-ray diffraction(XRD),Auger spectroscopy,transmission electron spectroscopy(TEM) and photoluminescence(PL).It was found that the Ca:Al molar ratios showed greatly influence not only on the particle size and morphology,but also on their PL spectra and *** the Ca:Al molar ratios increasing from 6:100 to 26:100,the structure of as-synthesized phosphor changed from CaAl12O19 to monoclinic CaAl2O4 and the dominant emitting light from red to blue,implying that the oxidation state of doped europium ions changed from trivalent to divalent due to the structure variation of host lattice.A blue phosphor with almost pure phase can be easily prepared by solution combustion method with suitable Ca:Al molar ratio.

关键词： CaAlxOy:Eu2+ solution-combustion molar ratio structure luminescence rare earths

Calculation of the VKI turbine blade with LES and DES

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Journal of Thermal Science 2007年第4期16卷 321-327页

作者： f.Magagnato b.Pritz M.Gabi fSM University of KarlsruheGermany

The prediction of the laminar to turbulent transition is essential in the calculation of turbine blades, compressor blades or airfoils of airplanes since a non negligible part of the flow field is laminar or transitional. In this paper we compare the prediction capability of the Detached Eddy Simulation （DES） with the Large Eddy Simulation （LES） using the high-pass filtered （HPf） Smagorinsky model （Stolz et al.[1]） when applied to the calculation of transitional flows on turbine blades. Detailed measurements from Canepa et al.[2] of the well known VKI-turbine blade served to compare our results with the experiments. The calculations have been made on a fraction of the blade （10%） using non-reflective boundary conditions of freund at the inlet and outlet plane extended to internal flows by Magagnato et al.[3] in combination with the Synthetic Eddy Method （SEM） proposed by Jarrin et al.[4]. The SEM has also been extended by Pritz et al.[5] for compressible flows. It has been repeatedly shown that hybrid approaches can satisfactorily predict flows of engineering relevance. In this work we wanted to investigate if they can also be used successfully in this difficult test case.

关键词： Turbine blade LES DES transition

A Large-Update feasible Interior-Point Algorithm for Convex Quadratic Semi-definite Optimization based on a New Kernel function

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Journal of the Operations Research Society of China 2013年第3期1卷 359-376页

作者： b.Kheirfam f.Hasani Department of Mathematics Azarbaijan Shahid Madani UniversityTabrizIran

In this paper we present a large-update primal-dual interior-point algorithm for convex quadratic semi-definite optimization problems based on a new parametric kernel *** goal of this paper is to investigate such a kernel function and show that the algorithm has the best complexity *** complexity bound is shown to be O(√n log n log n/∈).

关键词： Kernel function Interior-point algorithm Polynomial complexity Large-update methods