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Up-conversion emissions of Er^(3+)-Yb^(3+) codoped Al_2O_3 nanoparticles by the arc discharge synthesis method

science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 1043-1046页

作者： DONG Bin1, CAO BaoSheng1, FENG ZhiQing1, WANG XingJun2, LI ChengRen3 & HUA RuiNian4 1 School of science, dalian nationalities university, dalian 1.6600, china 2 School of Electronics Engineering and Computer science, Peking university, Beijing 100871, china 3 college of Physics and Electronic Technology, Liaoning Normal university, dalian 116029, china 4 college of life science, dalian nationalities university, dalian 1.6600, china 1. School of science Dalian Nationalities University Dalian 116600 China 2. School of Electronics Engineering and Computer science Peking University Beijing 100871 China 3. college of Physics and Electronic Technology Liaoning Normal University Dalian 116029 China 4. college of life science Dalian Nationalities University Dalian 116600 China

The Er3+-Yb3+ codoped Al2O3 nanoparticles with an average particle size of about 50 nm have been synthesized by an arc discharge synthesis method. The green and red up-conversion emissions centered at about 526, 547 and 677 nm, corresponding respectively to the 2H11/2→4I15/2, 4S3/2→4I15/2 and 4 F9/2→4I15/2 transitions of Er3+, were detected by a 978-nm semiconductor laser diode excitation. The Annealing has evident effect on the up-conversion emissions of the samples: The red up-conversion emission is noticeable before annealing; however, the green up-conversion emission becomes predominant after annealing. The mixture of (Er,Yb)3Al5O12 and α-(Al,Er,Yb)2O3 phases is more favorable for green up-conversion emissions due to an enhancement of the ESA (I) of 4I11/2+a photon→4F7/2 and ET (III) of 2F5/2(Yb3+)+4I11/2(Er3+)→2F7/2(Yb3+)+4F7/2(Er3+) processes. The two-photon absorption up-conversion process is involved in the green and red up-conversion emissions. The results have proved that arc discharge synthesis is a new promising preparation technology for optical materials.

关键词： up-conversion Er3+-Yb3+ codoped Al2O3 arc discharge synthesis

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Er^(3+)-Yb^(3+) codoped borosilicate glass for optical thermometry

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science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 848-851页

作者： FENG ZhiQing1,BAI Lan2,CAO BaoSheng1,GONG LiDong3 & DONG Bin1,4 1 School of science,dalian nationalities university,dalian 1.6600,china 2 college of Electromechanical & Information Engineering,dalian nationalities university,dalian 1.6600,china 3 School of Chemistry and Chemical Engineering,dalian 116029,china 4 Institute of Physics,Chinese Academy of sciences,Beijing 100190,china 1. School of science Dalian Nationalities University Dalian 116600 China2. College of Electromechanical & Information Engineering Dalian Nationalities University Dalian 116600 China3. School of Chemistry and Chemical Engineering Dalian 116029 China4. Institute of Physics Chinese Academy of Sciences Beijing 100190 China

Infrared to green up-conversion emissions centered at the wavelengths of about 524 and 550 nm of the Er3+-Yb3+ codoped borosilicate glass are recorded,using a 978 nm semiconductor laser diode(LD) as an excitation *** fluorescence intensity ratio(FIR) of the green up-conversion emissions at about 524 and 550 nm in the Er3+-Yb3+ codoped borosilicate glass has been studied as a function of temperature over the temperature range of 295-873 *** maximum sensitivity and the temperature resolution derived from the FIR of the green up-conversion emissions are approximately 0.0038 K-1 and 0.2 K,*** is demonstrated that the prototype optical temperature sensor based on the FIR technique from the green up-conversion emissions in the Er3+-Yb3+ codoped borosilicate glass plays a major role in temperature measurement.

关键词： Er3+-Yb3+ codoped optical temperature sensor fluorescence intensity ratio

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Multi-objective dynamic detection of seeds based on machine vision

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Progress in Natural science:Materials International 2007年第2期17卷 217-221页

作者： XUN Yi, ZHANG Junxiong, LI Wei and CAI Weiguo ( college of Engineering, china Agricultural university, Beijing 100083, china college of science, dalian Fisheries university, dalian 116023, china) [a]college of Engineering China Agricultural University Beijing China [b]college of science Dalian Fisheriers University Dalian China

An approach to inspecting massive numbers of moving seeds was studied based on the techniques of dynamic inspection and machine vision. A progressive scanning CCD camera with external trigger function was used for real-time capture of dynamic images of seeds. The methods based on R channel of RGB (Red, Green and Blue) and region-dependent segmentation were adopted to reduce the data size of image processing and improve the efficiency of seeds inspection. All the seeds were sorted into four grades according to their morphological characteristics, such as surface area, perimeter, major axis, minor axis, circularity and eccentricity. The detection experiments indicated that the eligible ratio of the classifications was about 81.90% by this real-time inspection system.

关键词： machine vision seed sorting multi-objective morphological parameter.

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Farmers' Willingness-to-Pay for Environment and Human Health and Adoption of IPM

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Chinese Journal of Population,Resources and Environment 2004年第3期2卷 39-44页

作者： Zhang Juyong dalian nationalities university, dalian 1.6600, china dalian nationalities university Dalian 116600 China

Although chemical control of pests increases crop production, it brings a lot of damage to environment and human health. There exist a number of alternative methods that are not so harmful to environment and human health. However, whether and how much in extent these technologies adopted are plausible depends on the comparison of benefit-cost between chemical control and the alternative control methods (such as Integrated Pest Management, IPM) and farmers' willingness-to-pay (WTP) for envirorment and human health. Using contingent valuation method (CVM), the author investigates farmers' WTP for environment and human health, recognizes the factors influencing WTP, and accordingly points out the importance of pest control technology extension and government regulation of pesticides.

关键词： contingent valuation method (CVM) environment human health Willingness-to-Pay (WTP) technology adoption

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Numerical simulation analysis of covering rock strata as mining steep-inclined coal seam under fault movement

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中国有色金属学会会刊：英文版 2011年第S3期21卷 556-561页

作者： MA Feng-hai, SUN Li, LI Dun college of Civil and Architectural Engineering, dalian university, dalian 116622, china college of Civil and Architectural Engineering Dalian University Dalian 116622 China

The fault is one important factor for the stability of overburden strata caused by steeply inclined coal seam. The stress and displacement change of overburden strata caused by steeply-inclined coal seam mining activity under faulting was simulated by FLAC2D finite differential program on the basis of Zhaogezhuang mining example belonging to Kailuan Mining Group. From the results, the stress and displacement clouding image after mining became complex because of the fault, that is, a kind of weak structural plane. The stress concentration region concentrated around the goaf, and also around the fault plane. As the mining depth increases, the stress and displacement within the fault zone change significantly. This movement and deformation characteristic of overburden strata can provide theoretical basis for the similar mining condition.

关键词： fault steep-inclined coal seam numerical simulation overburden distortion

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Structure and photochromic properties of molybdenumphosphoric acid/TiO_2 composite films

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science china Chemistry 2009年第2期52卷 169-173页

作者： QI He,LIU Yan,FENG Wei & ZHU YiMin college of Environmental science and Engineering,dalian Maritime university,dalian 116026,china 1. college of Environmental science and Engineering Dalian Maritime University Dalian 116026 China

TiO_2 sol-gel composite films with dropping molybdenumphosphoric acid(PMoA) have been prepared by sol-gel *** structure and constitute of composite thin films were studied with Fourier transforms infrared spectroscopy(FT-IR),atomic force microscopy(AFM),and X-ray diffraction(XRD) patterns,*** photochromic behavior and mechanism of composite thin films were inves-tigated with ultraviolet-visible spectra(UV-vis) and electron spin resonance(ESR).FT-IR results showed that the Keggin geometry of PMoA was still preserved inside PMoA/TiO2 composite thin films,and a charge transfer bridge was built at the interface of PMoA and TiO2 through the Mo-O-Ti *** topography of the composite film showed obvious changes before/after adding PMoA,and the surface topography of composite films showed obvious changes before/after irradiating as *** thin film had reversible photochromic *** with UV light,transparent films changed from colorless to blue and they can bleach completely with ambient air in the *** re-sults showed that TiO_2 were excitated by UV light to produce electrons,which deoxidized PMoA to produce *** photochromic process of PMoA/TiO_2 system was carried through elec-tron transfer mechanism.

关键词： molybdenumphosphoric acid TiO_2 composite film photochromism

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Construction of AFLP-based genetic linkage maps for the Chinese shrimp Fenneropaeneus chinensis

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Chinese science Bulletin 2008年第8期53卷 1205-1216页

作者： TIAN Yi1,2,3,4, KONG Jie1↑ & WANG WeiJi1 1 Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery science, Qingdao 266071, china 2 college of life science and Technology, dalian Fisheries university, dalian 116023, china 3 Institute of Oceanology, Chinese Academy of sciences, Qingdao 266071, china 4 Graduate university of Chinese Academy of sciences, Beijing 100049, china Chinese Acad Fisheries Sci Yellow Sea Fisheries Res Inst Qingdao 266071 Peoples R China.

Fenneropaeneus chinensis is an important species in marine fishery resources and aquaculture in china. A genetic linkage map is essential for improving the efficiency of its breeding by marker-as- sisted selection and identifying commercially important genes. Linkage maps of F. chinensis were constructed with an F2 mapping population (110 progenies) using amplified fragment length polymor- phic (AFLP) marker in this study. Fifty-five AFLP primer combinations produced 532 AFLP markers fitting for map strategy in mapping family. The markers with 3:1 segregating ratios were analyzed using F2 intercross model for the common linkage map, while the markers with 1:1 ratio were analyzed using the pseudo-testcross strategy. The maps of male, female and common were constructed. The female map included 103 markers that formed 28 linkage groups, covering a total length of 1090 cM. All mark- ers were linked with the linkage groups. Segregation distortion was observed for 6 of 103 markers in the female map. The average distance between markers was 14.53 cM and ranged from 4.4 to 24.8 cM. The male map included 144 markers that formed 35 linkage groups. Ten markers remained unlinked in male map. Segregation distortion was observed for 7 of 144 markers in the male map. The total dis- tance of male map covered 1617 cM. The average distance between markers was 16.36 cM. The male map was 32.6% longer than the female map, which may reflect sex-specific recombination rates in Chinese shrimp. The common map was composed of 216 markers, including in 44 linkage groups covering a total distance of 1772.1 cM. Two markers remained unlinked. No distorted markers of 216 markers were shown in the common map. The distance between markers was 10.42 cM. An average estimated genome size for the Chinese shrimp was 2420 cM, which was consistent with the relative size of the Penaeid genome. The distribution of AFLP markers was relatively even in chromosomes of Chi- nese shrimp maps. The linkage analysis

关键词： AFLP 海洋渔业虾中国

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Possibility of Constitutional Design and Its Theoretical Hypothesis

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学术界 2010年第12期 250-253页

作者： Ye Xingyi college of Humanities and Law,dalian nationalities university

Human society can construct a nicer government by way of political design and constitutional design is a basic approach to realize human good and construct a nicer modern *** beings have subjectivity and politics has the characteristics of goodness,which makes constitutional design *** design would follow some theoretical hypotheses,*** of gloom consciousness of humanity and hypothesis of essential evil of power.

关键词： Constitutional design subjectivity theoretical hypothesis

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Functions for patch test in finite element analysis of the Mindlin plate and the thin cylindrical shell

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science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 762-767页

作者： CHEN WanJi 1,2 ,WANG JinZhi 1,3 &ZHAO Jie 1 1State Key Laboratory for Structural Analysis of Industrial Equipment,dalian university of Technology,dalian 116023,china 2Institute for Structural Analysis of Aerocraft,Shenyang Institute of Aeronautical Engineering,Shenyang 110136,china 3 college of science,Institute of dalian nationalities,dalian 116022,china State Key Laboratory for Structural Analysis of Industrial Equipment Dalian University of Technology Dalian 116023 China Institute for Structural Analysis of Aerocraft Shenyang Institute of Aeronautical Engineering Shenyang 110136 China college of science Institute of Dalian Nationalities Dalian 116022 China

Current patch test for Mindlin plate element only satisfies the zero shear deformation *** patch test of non-zero constant shear for Mindlin plate problem cannot be *** shell element, the patch test does not even *** on the theory of enhanced patch test proposed by Chen W J (2006),the authors proposed the enhanced patch test function for Mindlin plate and thin cylindrical shell *** enhanced patch test function can be used to assess the convergence of the Mindlin plate and cylindrical thin shell elements.

关键词： Mindlin plate thin cylindrical shell finite element enhanced patch test test function

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Measurement and simulation of the two-phase velocity correlation in sudden-expansion gas-particle flows

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Acta Mechanica Sinica 2011年第4期27卷 494-501页

作者： Li-Xing Zhou.Yang Liu.Yi Xu Department of Engineering Mechanics,Tsinghua university,100084 Beijing,china Marine Engineering college,dalian Maritime university,116026 dalian,china Department of Engineering Mechanics Tsinghua University Beijing China Marine Engineering college Dalian Maritime University Dalian China

In this paper the present authors measured the gas-particle two-phase velocity correlation in sudden expansion gas-particle flows with a phase Doppler particle anemometer （PDPA） and simulated the system behavior by using both a Reynolds-averaged Navier-Stokes （RANS） model and a large-eddy simulation （LES）. The results of the measurements yield the axial and radial time-averaged velocities as well as the fluctuation velocities of gas and three particle-size groups （30μm, 50μm, and 95μm） and the gasparticle velocity correlation for 30μm and 50μm particles. From the measurements, theoretical analysis, and simulation, it is found that the two-phase velocity correlation of sudden-expansion flows, like that of jet flows, is less than the gas and particle Reynolds stresses. What distinguishes the two-phase velocity correlations of sudden-expansion flow from those of jet and channel flows is the absence of a clear relationship between the two-phase velocity correlation and particle size in sudden-expansion flows. The measurements, theoretical analysis, and numerical simulation all lead to the above-stated conclusions. Quantitatively, the results of the LES are better than those of the RANS model.

关键词： PDPA measurement - Simulation Two-phasevelocity correlation Sudden expansion gas-particle flows

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