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Wind Tunnel Study of Multiple Factors Affecting Wind Erosion from Cropland in Agro-pastoral Area of Inner Mongolia,China

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Journal of Mountain Science 2013年第1期10卷 68-74页

作者： HE Ji-jun cai Qiang-guo CAO Wen-qing State Key Laboratory Incubation Base of Urban Environmental Processes and Digital Simulation Elementary Educational CollegeCapital Normal University State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Water and Soil ConservationChinese Academy of Sciences and Ministry of Water Resources Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of Sciences

In this paper,the process of wind erosion on two kinds of soil from the agro-pastoral area of Inner Mongolia are studied using wind tunnel experiments,considering the wind speed,blown angle of wind and soil moisture *** results showed that the modulus of soil wind erosion increases with an increase of wind *** the wind speed exceeds a critical value,the soil wind erosion suddenly *** critical speed for both kinds of soil is within the range of 7-8m·*** a constant wind speed,the rate of soil wind erosion changes from increasing to falling at a critical soil *** critical slope of loam soil and sandy loam soil is 20° and 10°,*** moisture content has a significant effect on wind *** wind erosion of both soils decreases with an increase of the soil water content in two treatments,however,for treatment two,the increasing trends of wind erosion for two soils with the falling of soil water content are no significant,especially for the loam soil,and in the same soil water content,the wind erosion of two soils in treatment one is significantly higher than treatment two,this indicates reducing the disturbance of soil surface can evidently control the soil wind erosion.

关键词： Agro-pastoral area Soil wind erosion Critical slope Wind tunnel experiment

Dual Lie Bialgebra Structures of W-algebra W(2, 2) Type

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Acta Mathematica Sinica,English Series 2019年第10期35卷 1696-1714页

作者： Guang Ai SONG Yu cai SU Xiao qing YUE College of Mathematics and Information Science Shandong Technology and Business UniversityShandong 264005P.R.China School of Mathematical Sciences Tongji UniversityShanghai 200092P.R.China

In the present paper, we investigate the dual Lie coalgebras of the centerless W(2,2) algebra by studying the maximal good subspaces. Based on this, we construct the dual Lie bialgebra structures of the centerless W(2... 详细信息

关键词： W(2,2) algebra Lie bialgebra Lie coalgebra dual Lie bialgebra maximal good subspace

Kinetics of Precipitation Behavior of Second Phase Particles in Ferritic Ti-Mo Microalloyed Steel

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Journal of Iron and Steel Research International 2013年第7期20卷 69-77页

作者： HU Bin-hao cai qing-wu WU Hui-bin Engineering Research Institute University of Science and Technology Beijing

Two types of stress relaxation tests were carried out to investigate the incubation time for incipient precipi-tation of Ti（C,N） in deformed austenite and （Ti,Mo）C in ferrite of ferritic Ti-Mo microalloyed steel The size dis-tribution, amount and chemical composition of precipitates were obtained by using physicochemical phase analysis, and calculated according to thermodynamics and kinetics. The experimental results demonstrated that the incubation time was reduced with increasing Ti content, and prolonged with the addition of Mo. After 30 % deformation at 850 ℃, the nucleation of strain-induced Ti（C,N） was a relatively slow process. On the other hand, the temperature where the nucleation rate of （Ti, Mo）C in ferrite was the highest descended first and then ascended with increasing Ti content, and so did the temperature where the incubation time was the shortest. The key point is that the tempera-ture of steel containing about 0.09 % Ti is the lowest. The mass fraction of MC-type particles with size smaller than 10 nm in steel containing 0.09% Ti and 0.2% Mo reached 73.7%. The size distributions of precipitates in steel containing 0.09% Ti were relatively concentrated compared with that in steel containing 0.07% Ti.

关键词： ferritic Ti-Mo microalloyed steel precipitation behavior second phase particle stress relaxation parti-cle size distribution

Theoretical Study on Electronic Gain-and-loss Properties of TEMPO and Its Derivates in Charge/Discharge Processes

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Chinese Journal of Chemical Physics 2012年第2期25卷 161-168,I0003页

作者： Shu-cai Mao Jin-qing Qu Kang-cheng Zheng School of Chemistry and Chemical Engineering Zhongkai University of Agriculture and EngineeringGuangzhou 510225China School of Chemistry and Chemical Engineering South China University of TechnologyGuanEzhou 510640China School of Chemistry and Chemical Engineering Sun Yat-Sen UniversityGuangzhou 510275China

Theoretical study on the electronic structures and related properties of 2,2,6,6-tetramethyl- l-piperidinyloxy （TEMPO） and its cationic lipid derivates in the charge/discharge processes has been carried out using the density functional theory （DFT） at the （U）B3LYP/6-31G（d,p） or 6-31＋G（d,p） level. The changes and regularities of geometric and electronic properties of these compounds in the charge/discharge processes were revealed in detail. The compu- tational results show that the substitute group plays a very important role in the electronic structures and related properties of TEMPOs during the charge/discharge processes. It is very interesting to find that after getting an electron, TEMPO is more stable in singlet state but the lipid is more stable in triplet state. For TEMPO, both the charge and the discharge processes greatly influence the electronic properties of N and O atoms of the radical part. For the cationic lipid, the discharge process mainly influences the pyridinium head and the charge process mainly influences the free radical head. Moreover, the solvent effect plays an important role in some bond lengths and the charge population of the free radical head. In addition, the UV-Vis absorption spectra simulated using TDDFT at the 6-31G（d,p） with the experimental ones. of TEMPO and the lipid were calculated and or 6-31＋G（d,p） level, in satisfying agreement

关键词： 2,2,6,6-tetramethyl-l-piperidinyloxy Charge/discharge process Electronicstructure Density functional theory calculation

Calculating Method for Influence of Material Flow on Energy Consumption in Steel Manufacturing Process

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Journal of Iron and Steel Research International 2007年第2期14卷 46-51页

作者： YU qing-bo LU Zhong-wu cai Jiu-ju School of Materials and Metallurgy Northeastern University Shenyang 110004 Liaoning China

From the viewpoint of systems energy conservation, the influences of material flow on its energy consumption in a steel manufacturing process is an important subject. The quantitative analysis of the relationship between material flow and the energy intensity is useful to save energy in steel industry. Based on the concept of standard material flow diagram, all possible situations of ferric material flow in steel manufacturing process are analyzed. The expressions of the influence of material flow deviated from standard material flow diagram on energy consumption are put forward.

关键词： steel manufacturing process material flow energy consumption calculating method

Influence of Mo on Growth and Coarsening of Nanometer-sized Carbides in Low-alloy Ferritic Steels Containing Ti

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Journal of Iron and Steel Research International 2014年第9期21卷 878-885页

作者： Bin-hao HU qing-wu cai Hui-bin WU Engineering Research Institute University of Science and Technology Beijing

By optical microscopy, transmission electron microscopy and energy dispersive spectroscopy, the changes with aging time in size, composition and distribution of nanometer-sized （Ti, Mo）C precipitated in Ti-Mo low-alloy ferritc steel have been studied in comparison with that of nanometer-sized TiC precipitated in Ti low-alloy ferritc steel. It was found that the growth rate of （Ti,Mo）C in Ti-Mo steel was less than that of TiC in Ti steel. Nanometer- sized carbides formed at 650 ~C （or 550 ~C） for 55 h were at transitional stage from growth to coarsening. When aging time reaches 55 h, the coarsening rates of nanometer-sized carbides in Ti and Ti-Mo steel tend to be the same and in- variable. The influence of Mo on growth and coarsening of nanometer-sized carbides tends to decrease with increasing aging time, and Mo contents in nanometer-sized carbides with the same size at different aging time were different.

关键词： Ti-Mo low alloy ferritic steel nanometer-sized carbide precipitation strengthening Ostwald coarsening

Approximation properties for the genuine modi ed Bernstein-Durrmeyer-Stancu operators

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Applied Mathematics(A Journal of Chinese Universities) 2020年第4期35卷 468-478页

作者： cai qing-bo Ulku Dinlemez Kantar Bayram Cekim School of Mathematics and Computer Science Quanzhou Normal UniversityQuanzhou 362000China Department of Mathematics Faculty of ScienceGazi UniversityBesevler AnkaraTurkey

In this paper,we study on the genuine modified Bernstein-Durrmeyer-Stancu operators Gn(f,x)and investigate some approximation properties of ***,we present a Voronovskaja type theorem for these *** also give some graph... 详细信息

关键词： genuine modi ed Bernstein-Durrmeyer-Stancu operators Voronovskaja type approximation theorem rate of convergence modulus of continuity

Electrostatic force of dust deposition originating from contact between particles and photovoltaic glass

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Chinese Physics B 2021年第10期30卷 267-273页

作者： Xing-cai Li Juan Wang Guo-qing Su School of Physics and Electronic-Electrical Engineering Ningxia UniversityYinchuan 750021China Ningxia Key Laboratory of Intelligent Sensing&Desert Information Ningxia UniversityYinchuan 750021China Xinhua College of Ningxia University Yinchuan 750021China

Charged photovoltaic glass produces an electrostatic *** electrostatic field exerts an electrostatic force on dust particles,thus making more dust particles deposited on the *** this paper,the contact electrification between the deposited dust particles and the photovoltaic glass is ***,the surface charge density model of the photovoltaic glass and the electrostatic force of charged particles are *** results show that with the increasing of the particle impact speed and the inclination angle of the photovoltaic panel,the charges on particles increase to different *** a given condition,the electrostatic forces acting on the charged particles at different positions above the glass plate form a bell-shaped distribution at a macro level,and present a maximum value in the center of the *** the distance between the particle and the charged glass decreases,the electrostatic force exerted on the particle increases significantly and fluctuates ***,its mean value is still higher than the force caused by gravity and the adhesion force,reported by some ***,we suggest that photovoltaic glass panels used in the severe wind-sand environment should be made of an anti-static transparent material,which can lessen the dust particles accumulated on the panels.

关键词： particle electrification electrostatic force photovoltaic glass dust deposition

Abundance analysis of Barium stars

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Chinese Journal of Astronomy and Astrophysics 2009年第4期9卷 431-448页

作者： Guo-qing Liu Yan-Chun Liang Li-cai Deng National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

We obtain the chemical abundances of six barium stars and two CH subgiant stars based on the high signal-to-noise ratio and high resolution EcheUe spectra. The neu-Iron capture process elements Y, Zr, Ba, La and Eu show obvious overabundances relative to the Sun, for example, their [Ba/Fe] values are from 0.45 to 1.27. Other elements, including Na, Mg, A1, Si, Ca, Sc, Ti, V, Cr, Mn and Ni, show comparable abundances to the Solar ones, and their [Fe/H] covers a range from -0.40 to 0.21, which means they belong to the Galactic disk. The predictions of the theoretical model of wind accretion for binary systems can explain the observed abundance patterns of the neutron capture process elements in these stars, which means that their overabundant heavy-elements could be caused by accreting the ejecta of AGB stars, the progenitors of present-day white dwarf companions in binary systems.

关键词： stars abundances-stars atmospheres-stars chemically peculiar-stars evolution-binaries spectroscopic