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Infrared-to-Visible Frequency up-Conversion in Trivalent Erbium Ions Doped Fluoride Glasses (ZnF_2-Al_F3-PbF_2-LiF)

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Journal of Rare Earths 2003年第3期21卷 315-317页

作者：秦冠仕秦伟平黄世华吴长峰赵丹刘晃清 Changchun Institute of Optics Fine Mechanics and Physics Key Laboratory of Excited States Processes Chinese Academy of Sciences

High efficiency frequency up conversion in trivalent erbium ion doped new fluoride glass matrix (ZnF 2 AlF 3 PbF 2 LiF) was investigated. Under 950 nm laser diode excitation, the glasses gave very intense green, weak red and violet emissions. The up conversion mechanism is discussed. In addition, the infrared transmittance spectrum, the Raman spectrum and the lifetime of the trivalent erbium states in the samples were measured. The results illustrate the large potential of these new glasses for photonic applications.

关键词： optics fluoride glasses Er 3+ up conversion rare earths

Effects of Cadmium on Rat Sperm Motility Evaluated With Computer Assisted Sperm Analysis

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Biomedical and Environmental Sciences 2001年第4期14卷 312-317页

作者： XULI－CHUN WANGSHU－YI KeyLaboratoryforAppliedToxicologyofJiangsuProvince NanjingMedicalUniversityNanjing210029China KeyLaboratoryforAppliedToxicologyofJiangsuProvince NanjingMedicalUniversityNanjing

Objective To study effects of cadmium on rat sperm motility evaluated with computer assisted sperm analysis. Methods Different doses of cadmium chloride (0.2,0.4,0.8mg Cd/kg BW) were administrated ip to adult male Sprague_Dawley rats. Control animals received the same volume of 0.9% NaCl solution. After 7 days, the rats were sacrificed with their testes removed. A part of one testis was used for testicular sperm head counts and daily sperm production observation. The motility of spermatozoa obtained from cauda epididymides using the 'diffusion'method was measured by computer assisted sperm analysis(CASA). Results The sperm head counts and daily sperm production decreased significantly in the high dose group. The motility of spermatozoa in the middle dose group was reduced significantly. No motile sperm was found in the high dose group. The results suggest that germinal epithelium was impaired irreversibly in a short time to produce toxic effects on spermatogenesis at high cadmium doses. Conclusion Cadmium may reduce sperm motility at a dose far below the dose affecting sperm production at this time point. The motility of sperm is an early and sensitive endpoint for the assessment of cadmium toxicity on male reproduction.

关键词： MOTION PARAMETERS ANALYSIS SYSTEM VAS-DEFERENS OPTIMIZATION SPERMATOZOA FERTILITY CHLORIDE FAILURE TESTIS CAUDA

MODELING FOR THE DIFFUSION LIMITATION OF FREE RADICAL POLYMERIZATION

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2000年第2期 31-39页

作者：姚臻李伯耿曹堃黄源潘祖仁

A new model was developed to describe the diffusion limitation on free radical polyme\|rization. In this model the termination rate coefficient (\%k\%\-t) and propagation rate coefficient (\%k\%\-p) were expressed as a function of bulk viscosity (\%η\%). This model was used to simulate the batch thermal polymerization of styrene (St) and the continuous thermal bulk copolymerization of St (monomer 1) and maleic anhydride (MAH, monomer 2) in a CSTR with on line monitor of the rheological behavior. The simulated results on polymerization conversion, copolymer composition, molecular weight and its distributions were compared with the experimental data, and the results calculated by two previous gel effect models i.e. Martin Hamielec and Tulig Tirrell models. It was found that the present model produces better prediction than that of the Tulig Tirrell model and has the same accuracy as that of the Martin Hamielec model, but is much simpler.

关键词： modeling diffusion controlled polymerization bulk viscosity

Helium and Argon Isotopes of the Tertiary Volcanic Rocks, Shandong Peninsula: Significance for Crust Mantle Circulation

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Journal of China University of Geosciences 2005年第1期16卷 24-28页

作者： TangHuayun YuChunmei StateKeyLabofGeologicalProcessesandMineralResources ChinaUniversityofGeosciencesWuhan430074China；FacultyofEarthSciencesChinaUniversityofGeosciencesWuhan430074China FacultyofEarthSciences ChinaUniversityofGeosciencesWuhan430074China

He and Ar isotopes of the Tertiary volcanic rocks from Jiyang basin and nearby Shanwang and Qixia areas in Shandong peninsula have been analyzed. The results show that all samples are characterized by an enrichment of radiogenic 4He leading to extremely low 3He/ 4He ratios (0.017 8- 3.225)×10 -6 . They also have atmospheric like 38 Ar/ 36 Ar ratios and slightly higher 40 Ar/ 36 Ar ratios (395.4-1 312.7) than air value. The enrichment of radioactive 4He is attributed to the long term radiogenic accumulation of U and Th in the mantle. The low concentration of 3He is considered to be due to 3He loss during magma eruption. The loss is more obvious in the Neogene than in the Paleogene. Low 40 Ar/ 36 Ar ratios of all volcanic rocks may imply that subducted materials with atmospheric components have been preserved in the mantle, thus indicating that crust mantle circulation occurred.

关键词： He Ar isotope Tertiary volcanic rocks Shandong peninsula crust mantle circulation.

Anti-nutritional characteristics and mechanism of soybean agglutinin

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BIOCELL 2021年第3期45卷 451-459页

作者： LI PAN JIAWEI LIU MOHAMMED HAMDY FAROUK GUIXIN QIN NAN BAO YUAN ZHAO HUI SUN Key Laboratory of Animal Production Product Quality and SecurityMinistry of EducationKey Laboratory of Animal Nutrition and Feed ScienceCollege of Animal Science and TechnologyJilin Agricultural UniversityChangchun130118China Animal Production Department Faculty of AgricultureAl-Azhar UniversityCairo11884Egypt

Soybean agglutinin(SBA)is an important anti-nutritional factor in *** can induce animal growth inhibition,cause pathological changes of intestinal tissue,and decrease in the immune system ***,a great deal of research has been done on the effects of SBA on cell morphology,division,apoptosis,autophagy,as well as the correlated signal transduction *** review mainly covers the chemical and biological characteristics of SBA,describes the multifaceted aspects of SBA anti-nutritional functions,and highlights the possible cellular and molecular mechanism of anti-nutritional effects of *** review has important implications for the prevention and treatment of SBA-induced diseases,drug development,processing techniques of plant products,prevention of food-borne toxins,as well as human and animal health protection.

关键词： Soybean agglutinin Autophagy Cell apoptosis Anti-nutritional functions Cell signaling

EXACT ALGORITHM FOR BIN COVERING

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2001年第3期 2-7页

作者：陈峰姚恩瑜 Department of Applied Mathematics Zhejiang University Hangzhou 310027 China

This paper presents a new arc flow model for the one\|dimensional bin covering problem and an algorithm to solve the problem exactly through a branch\|and\|bound procedure and the technique of column generation. The subproblems occuring in the procedure of branch\|and\|bound have the same structure and therefore can be solved by the same algorithm. In order to solve effectively the subproblems which are generally large scale, a column generation algorithm is employed. Many rules found in this paper can improve the performance of the methods.

关键词： bin covering column generation branch\|and\|bound algorithm

VIDEO MOTION CAPTURE IN VBA——VIDEO-BASED ANIMATION

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2000年第1期1卷 4-10页

作者：潘云鹤庄越挺刘小明

Computer vision has very wide application in human motion capture research. This paper proposes a new approach to do motion capture in video. It is composed of image sequence based tracking of human feature points and the reconstruction of the three dimension(3D) motion skeleton. First, every part of the human body from top to bottom is tracked on the basis of a human model. The image difference and a morph block similarity algorithm based on subpixels are used. Then camera calibration is done using the line correspondences between the 3D model and the image. Finally the 3D motion skeleton is established by use of the model knowledge. This approach does not aim at a given mode of human motion. Rather, it analyzes large scale motion from frame to frame in complex, variational background, and sets up a 3D motion skeleton in the perspective projection. The experiment results are presented at the end of the paper.

关键词： video feature point image difference camera calibration skeleton.

VERTICAL LEAF SPECTRAL VARIATION AS AN INDICATOR OF NITROGEN NUTRITION STATUS IN RICE PLANTS

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2001年第3期2卷 50-54页

作者：周启发王人潮沈掌泉王秀珍于军平 College of Life ScienceZhejiang UniversityHangzhouChina College of Resource and EnvironmentZhejiang UniversityHangzhouChina

A field experiment was conducted to study the response of individual leaf spectral reflectance to five levels of nitrogen fertilizer treatments in rice\%(Oriza sativa L.)\% plants. Sampling was combined through a rice canopy at upper, medium and low levels for biomass, nitrogen and water content measurements with spectral signals from the leaves. The vertical gradients of leaf biomass ,nitrogen and water contents were associated with the nitrogen availability during tillering, panicle formation, initial heading and heading. Rice plants treated with the lowest rate of N could be characterized with the lowest value of gradient in leaf biomass and leaf water content and the highest value of gradient in leaf N concentration. A spectral gradient of single reflectance(R),ratio(RVI) and normalized difference(ND) of two individual reflectances was defined as this yielded a better relationship between the spectral data and leaf nitrogen concentration. The results suggested the spectral gradients may be used as an improved diagnostic tool for nitrogen status.

关键词： nitrogen status reflectance rice spectral gradient

Investigation on tribological behaviors of MoS2 and WS2 quantum dots as lubricant additives in ionic liquids under severe conditions

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Friction 2020年第4期8卷 674-683页

作者： Kuiliang GONG Wenjing LOU Gaiqing ZHAO Xinhu WU Xiaobo WANG State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Qingdao Center of Resource Chemistry&New Materials Qingdao 266000China

Despite excellent tribological behaviors of ionic liquids (ILs) as lubricating oils, their friction-reducing and anti-wear properties must be improved when they are used under severe conditions. There are only a few reports exploring additives for ILs. Here, MoS2 and WS2 quantum dots (QDs, with particle size less than 10 nm) are prepared via a facile green technique, and they are dispersed in 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIm]PF6), forming homogeneous dispersions exhibiting long-term stabilities. Tribological test results indicate that the addition of MoS2 and WS2 QDs in the IL can significantly enhance the friction-reducing and anti-wear abilities of the neat IL under a constant load of 500 N and a temperature of 150 °C. The exceptional tribological properties of these additives in the IL are ascribed to the formation of protective films, which are produced not only by the physical absorption of MoS2 and WS2 QDs at the steel/steel contact surfaces, but also by the tribochemical reaction between MoS2 or WS2 and the iron atoms/iron oxide species.

关键词： MoS2 and WS2 quantum dots ionic liquids lubricant additive friction reduction and anti-wear severe conditions