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Speciation Study of Trace Elements by Reversed Phase-High Performance Liquid Chromatography ( Ⅰ )——Simultaneous Determination of Cr( Ⅲ ) and Cr( Ⅵ )

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Chemical Research in Chinese Universities 1991年第1期7卷 37-41页

作者： Yao Xingdong , Liu Jinchun , Cheng Jieke Zeng Yun’ e (department of chemistry, Wuhan university, Wuhan ) To whom correspondence should be addressedPresent address: department of chemistry , Shantou university, Shantou.

Reported here is the Cr-speciation study by High Performance Liquid Chromatography (HPLC) using precolumn derivatization with ammonium pyrolidinyldithiocarbamate (APDC) and spectrophotometric detection. The rapid and sensitive method has been successfully applied to the analysis of environmental water. The chromatographic behavior of the two Cr-APDC chelates are illustrated with 'Solvophobic Theory'.

关键词： Trace elements Chromatographic behavior Cr-APDC chelate

Synergistic extraction of praseodymium with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline

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Journal of Shanghai university(English Edition) 2009年第1期13卷 72-75页

作者：张倩乌东北包伯荣 department of chemistry College of SciencesShanghai University department of chemistry Tongji University

The synergistic extraction of Pr^3＋ from hydrochloric medium using mixture of 2-ethylhexyl phosphonic acid mono- 2-ethylhexyl ester （P507, HL） and 8-Hydroxyquinoline （HQ） in heptane was investigated. The effect of equilibrium of aqueous acidity on extraction of Pr^3＋ was discussed. The effect of extractant concentraction, different diluents, equilibrium time and acetate ion concentration oil extraction reaction were also studied. With a method of double-logarithmic slope, composition of the extracted species on 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline was derived. The result shows that the synergistic extraction system not only overcomes emulsification of 8-Hydroxyquinoline, but also shows perfect capacity of synergistic extraction. The largest synergistic enhancement factor can be calculated to be 5.49 at pH 3.6 for Pr^3＋.

关键词： 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester 8-Hydroxyquinoline (HQ) synergistic extraction,praseodymium

Optical Properties of High Sensitivity Fiber Bragg Grating on Temperature Sensor

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光学学报 2003年第S1期23卷 843-844页

作者： Li Wang Shiya He department of Applied Physics, beijing university of Technology, beijing 100022, china department of Applied Physics Beijing University of Technology Beijing 100022 China

In this paper, the spectrum shift properties of the center reflection wavelength detected to be based on the FBG sensor with ambient temperature change. The basic theoretical methods and numerical simulation for the spectral properties of uniform Bragg grating is analyzed by using coupling mode theory which is optical properties of high sensitivity fiber Bragg grating on temperature sensor in accordance with experiment.

关键词： of in be et for FBG Optical Properties of High Sensitivity Fiber Bragg Grating on Temperature Sensor on

Environmental impact of electromagnetic radiation from the 10kWmedium wave transmitter of Weihai Broadcasting Station

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Journal of Environmental Sciences 1995年第4期7卷 461-467页

作者： Wen Congjiang Lu Deming Wang Shuquan,Wang Baosheng Hu Baoge(department of Physics , Ocean university of Qingdao, Qingdao 266003 , china)

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关键词： environmental impact assessment electromagnetic radiation broadcasting station electromagneticpollution.

MODULATED STRUCTURES AND ORDERIng STRUCTURES IN ALLOYIng AUSTENITIC MAngANESE STEEL

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 148-152页

作者： L. He, Z.H. Jin and J.D. Lu (department of Metallurgical Engineering, Guizhou university of Technology, Guiyang 550003, china) (Institute of Material Science and Engineering, Xi’an Jiaotong university,Xi’an 710049, china) Dept. of Metall. Eng. Guizhou Univ. of Technol. Guiyang 550003 China

The microstructure of Fe-10Mn-2Cr-1.5C alloy has been investigated with transmission electron microscopy and X-ray diffractometer. The superlattice diffraction spots and satellite reflection patterns have been observed in the present alloy, which means the appearance of the ordering structure and the modulated structure in the alloy. It is also proved by X-ray diffraction analysis that the austenite in the alloy is more stable than that in traditional austenitic manganese steel. On the basis of this investigation, it is suggested that the C-Mn ordering clusters exist in the austenitic manganese steel and the chromium can strengthen this effect by linking the weaker C-Mn couples together, which may play an important role in work hardening of the austenitic manganese steel.

关键词： Aging of materials Austenite Crystal structure Manganese alloys Microstructure

Comment on “Chen et al., Fabrication and photovoltaic conversion enhancement...”,Electrochimica Acta,2014

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Journal of Semiconductors 2015年第9期36卷 97-98页

作者： Lara Valentic Nima E.Gorji department of Environment Sciences,university of Nova Gorica department of Physics,Brown university department of Physics Brown University Providence 02912 Rhode Island USA

In a recent article, Chen et aL [Electrochimica Acta, 2014, 130： 279] presented their fabrication and characterization results on a graphene/n-Si solar cell where the Au nanoparticles were inserted in graphene to increase its optical and electrical properties. The higher efficiency of the device was attributed to increased conductivity of graphene after doping with Au nanoparticles. However, the knowledge in the field of Schottky diode solar cells relates this to increased band bending at the junction. Also, to explain the instability behaviour, they concluded that the growth of silicon oxide on the Si surface or oxygen adsorption on the window layer resulted in the device performance increasing initially and decreasing in the end. However, this instability seems to be due to variation in series resistance reduced at the beginning because of slightly lowered Fermi level and increased at the end by the self-compensation by deep in-diffusion ofAu nanoparticles into n-Si layer. We also propose that inserting a very thin p-type layer at the junction will enhance the carrier collection and performance of this device.

关键词： Shockley barrier solar cell graphene Si Au nanoparticle

Early Hydration of Composite Cement with Thermal Activated Coal Gangue

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Journal of Wuhan university of Technology(Materials Science) 2010年第1期25卷 162-166页

作者：郭伟 department of Material Engineering Yancheng Institute of Technology Institute of Material Science and Engineering Nanjing University of Technology

Composite cement samples were prepared by mixing clinker, gypsum with burnt coal gangues which was calcined at various temperatures. The mechanical strength and Ca（OH）2 content in the cement paste were tested, and the paste composition and microstructure were analyzed by thermogravimetry-differential thermal analysis （TG-DSC）, X-ray diffraction（XRD）, scanning electronic microscopy （SEM） and pore structure analysis. Results demonstrate that the thermal activated coal gangue could accelerate the early hydration of cement clinker obviously, which promotes the gangue hydration itself. The early hydrated products of the cement are C-S-H gel, Ca（OH）2 and AFt. The cement with 30% （in mass） the gangue exhibits higher mechanical strength, and among all the cement samples the one with the gangue burnt at 700 ℃ displays the highest hydration rate, mechanical strength, the most gel pores and the lowest total porosity.

关键词： blended cement hydration microstructure hydration product

FLOW PATTERNS AND FORCE CHARACTERISTICS OF LAMINAR FLOW PAST FOUR CYLINDERS IN DIAMOND ARRAngEMENT

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Journal of Hydrodynamics 2011年第1期23卷 55-64页

作者： ZOU Lin LIN Yu-feng LU Hong School of Mechanical and Electronic Engineering Wuhan University of Technology Wuhan 430070 China department of Mechanical Engineering The Hong Kong Polytechnic University Hong Kong China

A three-dimensional numerical investigation of cross-flow past four circular cylinders in a diamond arrangement at Reynolds number of 200 is carried *** the spacing ratios（L /D）ranging from 1.2 to 5.0,the flow patterns can be classified into three basic *** critical spacing ratio for the transition from narrow gap flow pattern to vortex impingement flow pattern around the cylinders is found to beL /D=3.0,while a single bluff-body flow pattern is observed atL /D=*** relationship between the three-dimensional flow patterns and force characteristics around the four cylinders shows that the variation of forces and Strouhal numbers againstL /D are generally governed by these three kinds of flow *** is concluded that the spacing ratio has important effects on the development of the free shear layers about the cylinders and hence has significant effects on the force and pressure characteristics of the four cylinders with different spacing ratios.

关键词： four cylinders spacing ratio flow pattern force characteristics

GURTIN VARIATIONAL PRINCIPLE AND FINITE ELEMENT SIMULATION FOR DYNAMICAL PROBLEMS OF FLUID-SATURATED POROUS MEDIA

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Acta Mechanica Solida Sinica 2003年第1期16卷 24-32页

作者： Yang Xiao Cheng Changjun department o,f Mechanics, Shanghai Institute of Applied Mathematics and Mechanics,Shanghai university,Shanghai 200436,china) department of Mechanics Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200436 China

Based on the theory of porous media, a general Gurtin variational principle for the initial boundary value problem of dynamical response of fluid-saturated elastic porous media is developed by assuming infinitesimal deformation and incompressible constituents of the solid and fluid phase. The finite element formulation based on this variational principle is also derived. As the functional of the variational principle is a spatial integral of the convolution formulation, the general finite element discretization in space results in symmetrical differential-integral equations in the time domain. In some situations, the differential-integral equations can be reduced to symmetrical differential equations and, as a numerical example, it is employed to analyze the reflection of one-dimensional longitudinal wave in a fluid-saturated porous solid. The numerical results can provide further understanding of the wave propagation in porous media.

关键词： saturated porous media Gurtin variational principle finite element method longitudinal wave