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Communications in Theoretical Physics 2008年第12期50卷 1417-1421页

作者： liU Wen-Juan li yao-Yi School of Science Hunan University of Technology Zhuzhou 412008 China Department of Physics Wuhan University Wuhan 430072 China State Key Laboratory for Surface Physics Institute of Physics the Chinese Academy of Sciences Beijing 100080 China

The statistic properties of photon emissions from single semiconductor quantum dots with V-type leveldriven by pulses are investigated *** on quantum regression theorem and master equations,the dynamicequations of the second-order correlation function of the photon emissions are *** calculated results reveal thatthe efficiency of single photon emissions from two orthogonal polarization eigenstates(|x〉and |y〉)reaches the maximumwhen the input pulses area is about π,and the probability of the cross-polarized single photon emission from |x〉and |y〉decreases with increasing of pulse width.

关键词： semiconductor quantum dots cross-polarized single photon emission V-type system

Spatial differentiation in stable isotope compositions of surface waters and its environmental significance in the Issyk-Kul Lake region of Central Asia

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Journal of Mountain Science 2018年第2期15卷 254-263页

作者： MA Long JIlili Abuduwaili li yao-ming State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China CAS Research Center for Ecology and Environment of Central Asia Urumqi 830011 China

Stable isotope values of oxygen （180） and hydrogen （2H） of surface waters were used to study the origin and environmental significanees in the Issyk-Kul basin of Kyrgyzstan in Central Asia, which is the most important intermountain basin in the modern Tien Shan orogen. This study is the first analysis of hydrochemical spatial differentiation in the stable isotopes of surface waters in this watershed. 75 samples were collected from rivers, springs, lakes, rain and snow during the rainy season in July and August of 2o16. Stable isotopes of 180 and 2H were studied for all samples, and cation ratios （Sr/Ca and Mg/Ca） were also determined for lake water samples. Stable isotope values from precipitation scattered around the Local Meteoric Water line （determined from Urumqi Station of the global network of isotopes in precipitation （GNIP））, together with values of the Deuterium excess parameter （d） from 15.3‰ to 30.5‰, with an average of 19.8‰, indicating that the moisture sources are primarily from regions with low relative humidity. The 8180 and 52H values were significantly different between the river and lake samples, indicating that regional evaporation caused the isotopic enrichment of lake water. Geospatial autocorrelation, measured by Moran＇s I coefficient, indicated weak spatial autocorrelation within stable isotopes of oxygen and hydrogen in the surface waters of the studied area, which is primarily an effect of climate during the water chemistry evolution. The cation ratios Sr/Ca and Mg/Ca in lake water samples were not correlated with the concentration of total dissolved solids, but did show correlation with stable isotopic values, which is significant for paleoenvironmental reconstruction.

关键词： Spatial differentiation Stable isotope Moisture Sources Geospatial autocorrelation IssykKul Lake Central Asia

Effect of Low Temperature on Hydration Performance of the Complex Binder of Silica Fume-Portland Cement

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Journal of Wuhan University of Technology(Materials Science) 2014年第1期29卷 75-81页

作者：刘军 li yao YANG Yuanquan CUI Yunpeng Institute of Civil Engineering Dalian University of Technology School of Material Science and Engineering Shenyang Jianzhu University School of Material Science and Engineering Shenyang Ligong University

By analyzing the mechanical properties, composition of hydrates, content of Ca（OH）： and microstructure of the complex binder of silica fume-Portland cement, which cured at constant low temperatures（＋5--10 ℃）, the effect of different low temperatures on hydration performance of the complex binder at the age of 3, 7 days and 14 days was researched. Experimental results show that hydration processes of the complex binder can be restricted by low temperature. Reducing the curing temperature could cause compressive strength and flexural strength of the complex binder to decrease significantly. The gradient difference between strength diminishes, content of Ca（OH）2 in hydrates reduces, and compactness of the microstructure weakens. Therefore mixing with silica fume can modify various performance indicators of the complex blinder, but reducing the curing temperature restricts the pozzolanic activity of silicon fume.

关键词： low temperature strength content of Ca(OH)2 XRD analysis SEM

Oxygen-suppressed selective growth of monolayer hexagonal boron nitride on copper twin crystals

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Nano Research 2017年第3期10卷 826-833页

作者： Xuemei li yao li Qin Wang Jun Yin Jidong li Jin Yu Wanlin Guo State Key Laboratory of Mechanics and Control of Mechanical Structures Key Laboratory for Intelligent Nano Materials and Devicesof the Ministry of Education and Institute of Nanoscience Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Controlled growth of hexagonal boron nitride （h-BN） with desired properties is essential for its wide range of applications. Here, we systematically carried out the chemical vapor deposition of monolayer h-BN on Cu twin crystals. It was found that h-BN nucleated and grew preferentially and simultaneously on the narrow twin crystal strips present in the Cu substrates. The density functional theory calculations revealed that the introduction of oxygen could effidently ~ne the selectivity. This is because of the reduction in the dehydrogenation barrier of the precursor molecules by the introduction of oxygen. Our findings throw light on the direct growth of functional h-BN nanoribbons on nano-twinned crystal strips and switching of the growth behavior of h-BN films by oxygen.

关键词： monolayer hexagonalboron nitride copper twin crystals oxygen selectivity chemical vapor deposition

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精准饲喂对个体奶牛甲烷排量的影响

农机化研究 2025年第3期47卷 156-161页

作者：叶岩崔振兴李源源杨存志侯云涛李尧孙先明黑龙江省农业机械工程科学研究院哈尔滨150081 哈尔滨完达山奶牛养殖有限公司哈尔滨150528

反刍动物奶牛的甲烷排放是农业温室气体主要排放源之一,而采食量是影响个体奶牛甲烷排量的重要因素,故研制个体奶牛精准饲喂系统和利用甲烷检测装置分析奶牛采食量对甲烷排量的影响,对提高奶牛健康水平、提高饲料利用率和奶牛科学饲养... 详细信息

反刍动物奶牛的甲烷排放是农业温室气体主要排放源之一,而采食量是影响个体奶牛甲烷排量的重要因素,故研制个体奶牛精准饲喂系统和利用甲烷检测装置分析奶牛采食量对甲烷排量的影响,对提高奶牛健康水平、提高饲料利用率和奶牛科学饲养管理能力等方面均具有重要意义。为此,设计了个体奶牛精准饲喂系统和甲烷检测装置,利用个体奶牛穿戴式“牛衣”和牧场内主体框架分布网点固定安装相结合的方法,采集对照组和试验组各3头奶牛采食前后奶牛后肠道甲烷排量和奶牛嗳气与呼吸的甲烷排量。研究表明,个体奶牛精准饲喂系统可依据奶牛个体差异实现饲料的定量饲喂,相同条件下精准饲喂和自由采食的个体奶牛甲烷排量和产奶量有差异但不显著,且随着个体奶牛采食量增加,甲烷排量会随之升高,说明饲喂量与甲烷排量之间存在正相关关系。

关键词：精准饲喂甲烷排量奶牛

NUMERICAL INVESTIGATION OF PERFORMANCE OF AN AXIAL-FLOW PUMP WITH INDUCER

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Journal of Hydrodynamics 2007年第6期19卷 705-711页

作者： li yao-jun WANG Fu-jun College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 China

The interaction of flow through the inducer and impeller of an axial-flow pump equipped with an inducer has significant effect on its performance. This article presents a recent numerical investigation on this topic. The studied pump has an inducer with 3 blades mounted on a conical hub and a 6-blade impeller. The blade angle of the impeller is adjustable to generate different relative circumferential angles between the inducer blade trailing edge and the impeller blade leading edge. A computational fluid dynamics code was used to investigate the flow characteristics and performance of the axial-flow pump. For turbulence closure, the RNG k-ε model was applied with an unstructured grid system. The rotor-stator interaction was treated with a Multiple Reference Frame （MRF） strategy. Computations were performed in different cases： 7 different relative circumferential angles （ Δθ ） between the inducer blade trailing edge and the impeller blade leading edge, and 3 different axial gaps （G） between the inducer and the impeller. The variation of the hydraulic loss in the rotator was obtained by changing Δθ . The numerical results show that the pressure generated is minimum in the case of （ G = 3%D）, which indicates that the interference between inducer and impeller is strong if the axial gap is small. The pump performances were predicted and compared to the experimental measurements. Recommendations for future modifications and improvements to the pump design were also given.

关键词： axial-flow pump inducer CFD numerical simulation of flow

Bending-induced extension in two-dimensional crystals

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Acta Mechanica Sinica 2017年第1期33卷 71-76页

作者： Douxing Pan yao li Tzu-Chiang Wang Wanlin Guo State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Mechanics and Control for Mechanical Structures and Key Laboratory for Intelligent Nano Materials and Devices (MOE) Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

We find by ab initio simulations that significant overall tensile strain can be induced by pure bending in a wide range of two-dimensional crystals perpendicular to the bending moment, just like an accordion being bent to open. This bending-induced tensile strain increases in a power law with bent curvature and can be over 20% in monolayered black phosphorus and transition metal dichalcogenides at a moderate curvature of but more than an order weaker in graphene and hexagon boron nitride. This accordion effect is found to be a quantum mechanical effect raised by the asymmetric response of chemical bonds and electron density to the bending curvature.

关键词： Monolayer black phosphorus Bending to extension Accordion effect Density functional theory

Dual Convergence of Facial Nerve Branches Innervating Whisker Pad in Rats

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Current Medical Science 2018年第6期38卷 982-988页

作者： lin-li yao E ZHANG Chun-li li Qi yao Chang HUANG Xi HUANG Pei CHEN Department of Otolaryngology Wuhan Hospital of Traditional Chinese and Western Medicine (Wuhan No.1 Hospital)Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

The precise anatomy of the facial nerve branches innervating rat whisker pad and the distribution of their corresponding motor neurons in facial nucleus area were *** extratemporal facial nerves of 6 rats were anatomically observed under a surgical microscope,and then the nerve specimens of facial nerve branches at 7 anatomical sites were taken and examined for the axons and myelin sheath using Luxol fast blue *** distribution of facial motor neurons innervating the facial branches was observed in 12 rats by retrograde *** distal pes,a fusing architecture of the buccal and marginal mandibular branches,was found to furcate into superior,middle and inferior branches to innervate whisker ***,the myelin sheath of each branch was morphologically consistent,and the nerve fiber bundles of facial nerve branches became increasingly thinner and scattered,particularly after crossing the distal pes site and innervating the whisker *** facial motor neurons innervating the buccal and marginal mandibular branches were clearly distributed in similar regions in facial *** study confirmed the highly spatial synergy between the buccal and marginal mandibular branches innervating the whisker pad from extratemporal anatomy and distribution of facial motor neurons.

关键词： facial nerve whisker pad anatomy facial nucleus rats

Bioimage-based protein subcellular location prediction： a comprehensive review

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Frontiers of Computer Science 2018年第1期12卷 26-39页

作者： Ying-Ying XU li-Xiu yao Hong-Bin SHEN Institute of Image Processing and Pattern Recognition Shanghai Jiao Tong University Shanghai 200240 China Key Laboratory of System Control and Information Processing Ministry of Education of China Shanghai 200240 China

Subcellular localization of proteins can provide key hints to infer their functions and structures in cells. With the breakthrough of recent molecule imaging techniques, the usage of 2D bioimages has become increasingly popular in automatically analyzing the protein subcellular location pat- terns. Compared with the widely used protein 1D amino acid sequence data, the images of protein distribution are more intuitive and interpretable, making the images a better choice at many applications for revealing the dynamic char- acteristics of proteins, such as detecting protein translocation and quantification of proteins. In this paper, we systemati- cally reviewed the recent progresses in the field of automated image-based protein subcellular location prediction, and clas- sified them into four categories including growing of bioim- age databases, description of subcellular location distribution patterns, classification methods, and applications of the pre- diction systems. Besides, we also discussed some potential directions in this field.

关键词： bioimage informatics protein subcellular loca-tion prediction global and local features multi-location pro-tein recognition

Transient Expression of Exogenous Gene into Plant Cell Mediated by PEI Nanovector

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Agricultural Sciences in China 2011年第6期10卷 820-826页

作者： li Ying CUI Hai-xin SONG Yu li yao HUANG Jin-li Institute of Agricultural Environment and Sustainable Development Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China

This study was carried out to investigate the transfection effect of exogenous gene into plant protoplast cell mediated by polyethylenimine （PEI） nanovector, based on PEI gene delivery system in the field of medical science. PEI/DNA complexes were prepared by using PEI polymer to bind the plant expression plasmid, pCMl205-GFPn. The ability of PEI combining and protecting DNA was investigated by agarose gel electrophoresis retardation assay. The surface characteristics of PEI/DNA complexes were observed with transmission electron microscope. The transfection efficiency of Arabidopsis thaliana protoplasts mediated by PEI/DNA complexes at different N/P ratios was analyzed based on observation of transient expression of green fluorescent protein with confocal laser scanning microscope. PEI could bind and condense DNA, and form stable 100-200 nm PEI/DNA complexes when the proportion of PEl and DNA is in the range of 5：1-1：4. Transfection efficiency of PEI/DNA complexes increased with N/P ratios in range of N/P〈5 and reached the highest at N/P=5, and began to decrease beyond N/P〉5 as higher toxicity to cells. The transfection efficiency of PEI/DNA complexes at N/P=5 was higher than PEG. This study confirmed that PEI nanovector could effectively mediate foreign gene entering into A. thaliana protoplast cell to obtain transient expression, which may be developed as a hopeful and novel transgenic method combined with plant protoplast regeneration.

关键词： polyethylenimine gene nanovector plant cell transient expression Arabidopsis thaliana protoplast