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Topological Charge Conversion with Spiral-Slit Screens

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Chinese Physics Letters 2013年第10期30卷 108-111页

作者： LI Zhen-Hua ZHANG Mei-Na LI Xing liu chun-xiang cheng chuan-fu College of Physics and Electronics Shandong Normal UniversityJinan 250014

We propose a method of converting the topological charge(TC)of an incident vortex light wave with spiral-slit *** phase in the incident vortex beam is redistributed via the optical path adjustment realized by changing the in-plane radial distance of the spiral *** numerically calculate the light field with Fresnel diffraction theory,and find the expected TC conversion on the observation *** calculations also show that screens of pinholes distributed in a spiral curve can be used for the implementation instead of spiral *** method can also be used to distinguish the TCs of the incident vortices by reading the diffracted intensity patterns.

关键词： incident vortex topological

Measurement of Random Surface Parameters by Angle-Resolved In-plane Light Scattering with Constant Perpendicular Wave Vector

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Chinese Physics Letters 2011年第2期28卷 105-108页

作者： LI Hai-Xia liu chun-xiang CHEN Xiao-Yi ZHANG Mei-Na cheng chuan-fu College of Physics and Electronics Shandong Normal UniversityJinan 250014 Department of Information Science and Technology Shandong University of Politics Science and LawJinan 250014

We report the experimental method of angle-resolved in-plane light scattering for random surface parameter *** the measurement of the scattered intensity profile at a certain angle of incidence,the perpendicular component of wave vector remains constant,which is realized by controlling the movement of the detector along a specified circular arc *** use the central S-peak and the half-width of the diffused intensity profiles and their variations to obtain the roughness w,the lateral correlation lengthξand roughness exponent a of the rough surface *** measurement copes strictly with the theoretical analysis,and the inherent problem in previous in-plane light scattering experiment is overcome so that the changes of the perpendicular component of wave vector affect the half width a diffused intensity profile and the measurement accuracy.

关键词： plane roughness overcome

The Multi-Scale and the Multi-Fractality Properties of Speckles on Rough Screen Surfaces

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Chinese Physics Letters 2013年第4期30卷 105-109页

作者： ZHANG Mei-Na LI Zhen-Hua CHEN Xiao-Yi liu chun-xiang TENG Shu-Yun cheng chuan-fu College of Physics and Electronics Shandong Normal UniversityJinan 250014 School of Physics and Technology University of JinanJinan 250022

With a microscopic imaging system composed of microscopic objective,lens and CCD,we observe the complicated structures in the speckle fields on the surface of a rough *** is found that such structures contain ridge stripes,large platform-like grains,and shivy grains,exhibiting multiple scales in size and multiple *** shows these structures are formed by different parts of the rough *** experimental curve of the autocorrelation function of the speckle intensity includes the three parts of the central peak,the transition part and the long tail *** the sum of self-affine fractal models with different scales and fractalities,we propose theoretically a triple-scale autocorrelation function to describe the speckle *** of this autocorrelation function to the experimental curve gives the values of such parameters as average speckle sizes and fractalities in different scales of the speckle structures.

关键词： surface. field. speckle

Minimum Amount of Extracting Solvent of (A_(1)A_(2)…A_(t−1))/(A_(2)A_(3)…A_(t)) Separation When Using Non-barren Extracting Solvent

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Chinese Journal of Chemistry 2014年第10期32卷 1022-1028页

作者： fu-xiang cheng Sheng Wu Song-Ling Wang Bo Zhang Yan liu chun-Sheng Liao chun-Hua Yan Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU-HKU Joint Lab on Rare Earth Materials and Bioinorganic ChemistryPeking UniversityBeijing 100871China China Minmetals(Beijing)Research Institute of RE Co. LtdBeijing 100085China

Hyperlink extraction technology,by virtue of its remarkable advantage of decreasing the use of chemicals in multi-component separation,has been extensively employed in rare earth separation industry in *** hyperlink processes,non-barren extracting solvent and scrubbing agent solution which contain the component(s)involved in starting feed are employed in order to save both alkali for saponification and acid for *** amount of extracting solvent(denoted as S_(min))and that of scrubbing agent solution(denoted as W_(min))are important parameters to determine the consumption amounts of alkali and acid for a given countercurrent extraction *** article therefore discusses the influence of using non-barren extracting solvent and scrubbing agent solution on S_(min) and W_(min) of an(A_(1)A_(2)…A_(t−1))/(A_(2)A_(3)…A_(t))*** equations for S_(min) and W_(min) are derived,and the variation of the composition of final raffinate as well as that of final extract are determined,which will provide a valuable guidance for the design of hyperlink extraction processes of multi-component separation,such as rare earths separation.

关键词： minimum amount of extracting solvent rare earths hyperlink process multi-component separation

Instability characteristics of a co-rotating wingtip vortex pair based on bi-global linear stability analysis

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Chinese Journal of Aeronautics 2021年第5期34卷 1-16页

作者： Zepeng cheng Siyi QIU Yang xiang chun SHAO Miao ZHANG Hong liu School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Aircraft Design and Research Institute Commercial Aircraft Corporation of China Ltd.Shanghai 201210China

The Stereo Particle Image Velocimetry(SPIV)technology is applied to measure the wingtip vortices generated by the up-down symmetrical split ***,the temporal biglobal Linear Stability Analysis(bi-global LSA)is performed on this nearly equal-strength corotating vortex pair,which is composed of an upper vortex(vortex-u)and a down vortex(vortex-d).The results show that the instability eigenvalue spectrum illustrated by(ωr,ω_(i))contains two types of branches:discrete branch and continuous *** discrete branch contains the primary branches of vortex-u and vortex-d,the secondary branch of vortex-d and coupled branch,of which all of the eigenvalues are located in the unstable half-plane ofω_(i)>0,indicating that the wingtip vortex pair is temporally *** contrast,the eigenvalues of the continuous branch are concentrated on the half-plane ofω_(i)further investigating the topological structures of Mode P_(u) and Mode Pd with streamwise wavenumbers,the most unstable perturbation mode with a large azimuthal wavenumber of m=5-6 is identified,which imposes on the entire core region of *** large azimuthal wavenumber perturbation mode can suggest the potential physical-based flow control strategy by manipulating it.

关键词： Bi-global linear stability analysis Perturbation mode SPIV Vortex flow Winglet Wingtip vortex

Study on the active sites of Cu-ZSM-5 in trichloroethylene catalytic combustion with air

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Chinese Chemical Letters 2008年第11期19卷 1387-1390页

作者： cheng Hua Xu chuan Qi liu Yan Zhong Xiu Zhou Yang Jian Ying liu Ying chun Yang Zhi xiang Ye Department of Environmental Engineering Chengdu University of Information Technology （CULT） Chengdu 610225 China

The catalytic activity of Cu-ZSM-5 in trichloroethylene （TCE） combustion increases with the increasing skeletal Cu amount and however decreases with the increase of surface amorphous CuO, which is detected by infrared spectroscopy （IR） and diffuse reflectance ultraviolet-visible spectroscopy （DRS-UV-vis）, therefore the skeletal Cu species are concluded to be the active sites for the TCE combustion.

关键词： Cu-ZSM-5 Active sites Trichloroethylene Catalytic combustion

Effect of vortex dynamics and instability characteristics on the induced drag of trailing vortices

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Chinese Journal of Aeronautics 2022年第9期35卷 160-173页

作者： Zepeng cheng Shiyan ZHANG Yang xiang chun SHAO Miao ZHANG Hong liu Yingchun CHEN School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Aircraft Design and Research Institute Commercial Aircraft Corporation of China Ltd.Shanghai 201210China

In this paper, trailing vortices generated by three wingtip configurations, namely the M6wing and the M6 wing with a blended or split winglet, are experimentally investigated using the Stereo Particle Image Velocimetry(SPIV) technology. Then, linear stability analysis is performed to investigate instability characteristics. Three corresponding trailing vortex patterns, including the isolated trailing vortex without wake(pattern v) and with wake(pattern v-w), co-rotating vortex pair(pattern v-v), are observed in experiments. The strength of trailing vortices, characterized by circulation, is reduced after installing winglets as expected, and the strength of pattern v-v can be further suppressed compared with pattern v-w. Moreover, instability characteristics, such as the eigenvalue spectrum and perturbation mode, are distinctive among these three vortex *** distribution of eigenvalue spectrums indicates that pattern v and pattern v-w are temporally“marginally stable”, while pattern v-v is temporally “unstable.” The primary perturbation mode of pattern v and pattern v-w is the m =-1 helical mode, while |m|>1 for the case of pattern *** effect of vortex dynamics and instability characteristics can be concluded in two ***, the value of induced drag is polluted by about 3% from vortex wandering since vortex wandering affects the tangential velocity and streamwise vorticity of trailing vortices. Secondly, the growth rate and penetration depth perturbation mode affect trailing vortex evolution and further affect induced drag. Specifically, the larger the growth rate and penetration depth are, the more turbulence injects inside the vortex core, thus leading to a quicker and more intense attenuation of trailing vortex, as well as a smaller induced drag. This finding can guide us to manipulate the induced drag in flow control.

关键词： Induced drag Linear stability analysis SPIV Trailing vortex Vortex flow Winglet

Constitutive model for Ya'an mudstone based on mesoscopic breakage mechanism

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Journal of Mountain Science 2023年第4期20卷 1159-1169页

作者： HE Yun-yong CHEN Cong WANG fu-ming GUO cheng-chao xiang Bo YU Di liu En-long DING chun School of Civil Engineering Southwest Jiaotong UniversityChengdu610031China Sichuan Highway Planning SurveyDesign and Research Institute LtdChengdu610041China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resources and HydropowerSichuan UniversityChengdu610065China School of Civil Engineering Sun Yat-sen UniversityGuangzhou510275China Ya’an Transportation Construction Group Co. Ltd.Ya’an625000China

The slope stability of Ya’an expressway in Sichuan dominated by mudstone strata,is influenced greatly by both the mechanical properties and stressstrain relationship of *** this paper,the mechanical properties of the Ya’an mudstone samples under triaxial compression conditions were studied,based on an established constitutive model under the framework of breakage mechanics to simulate the mechanical properties of ***,triaxial compression tests and SEM tests at the confining pressures of 0.5 MPa,1.0 MPa,and 2.0 MPa were carried out on the mudstone samples,and it was found that the mudstone sample undergoes strain softening and dilatancy followed by the volumetric ***,based on analysis on the breakage mechanism of the above test results,we idealized the mudstone sample as a binary medium material consisting of the bonded elements and frictional elements,of which the bonded elements are composed of solid matrix and pores,and the frictional elements are composed of broken *** the loading process,the cementation between clay minerals and non-clay minerals in the mudstone sample is first destroyed,leading to the formation of micro-cracks within the particle aggregate,that is,the bonded elements are gradually damaged during the loading process and gradually turned into the frictional elements,and the two jointly bear the external *** bonded elements are composed of mudstone matrix and pores,which have the cementitious characteristics of mudstone,and the frictional elements are composed of the broken aggregate with the frictional characteristics of the broken *** on the homogenization theory,the constitutive model for the mudstone is established,and the determining method for model parameters is also ***,the results of the triaxial compression tests of the mudstone samples are predicted by the constitutive model proposed here,which can reflect the main mechanical properties of the mudstone samples.

关键词： Mudstone Breakage mechanism Constitutive model Strain softening Binary medium model

Mapping of the heading date gene HdAey2280 in Aegilops tauschii

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Journal of Integrative Agriculture 2016年第12期15卷 2719-2725页

作者： liu Guo-xiang ZHANG Li-chao XIA chuan JIA Ji-zeng ZHANG Jun-cheng ZHANG Qiang DONG chun-hao KONG Xiu-ying liu Xu Key Laboratory of Crop Germplasm Resources and Utilization Ministry of Agriculture/National Key Facility for Crop Gene Resources and Genetic ImprovementInstitute of Crop SciencesChinese Academy of Agricultural Sciences

An optimum heading date is essential for sustainable crop productivity and ensuring high yields. In the present study, F2：3 populations were generated by crossing an early-heading accession, Y2280, with a late-heading accession, Y2282. The heading dates of the F2 and F3 populations were investigated in a field study. Using publicly available simple sequence repeat （SSR） markers, the early heading date gene HdAey2280 was mapped onto Aegilops tauschfi chromosome 7DS between the flanking markers wmc438 and barc126 at distances of 15 and 9.1 cM, respectively. further analysis indicated that HdAey2280 is a novel heading date gene. New SSR markers were developed based on the Ae. tauschfi draft genome sequence, resulting in four new markers that were linked to the heading date gene HdAey2280. The closest distance of these markers was 1.9 cM away from the gene. The results collected in this study will serve as a framework for map-based cloning and marker-assisted selection in wheat breeding programs in the future.

关键词： Aegilops tauschii heading date molecular markers HdAey2280