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Optical quantum simulation of Abelian gauge field using cold atomic ensembles coupled with arrays of optical cavities

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Science China(Physics,Mechanics & Astronomy) 2014年第12期57卷 2259-2265页

作者： LIU Yi Min LIU rong wan Department of Physics Shaoguan University

A potentially practical scheme is proposed to realize optical quantum simulation of artificial Abelian gauge field in a scalable architecture consisting of cold atomic ensembles with optical *** the present model,the collective excitations of cold atomic ensembles can be converted to the bosonic modes within the low-excitation limit,where the structure of two-dimension(2D)square plaquette enables the polaritons to move like a charged particle subjected to an external magnetic *** find that the energy spectrum of this hybrid system exhibits a shape of Hofstadter *** work provides a different perspective to the quantum simulation of condensed matter and many-body physics in the context of cavity quantum *** experimental feasibility are justified using the existing techniques.

关键词： gauge field quantum information processing cavity array

Limited Effect of Twin Boundaries on Radiation Damage

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Acta Metallurgica Sinica(English Letters) 2016年第1期29卷 72-78页

作者： Jin Gao Zhi-Jun Liu Fa-rong wan Department of Materials Physics and Chemistry School of Materials Science and EngineeringUniversity of Science and Technology Beijing

The different influences of the general grain boundary and the twin boundary on the cavity formation were investigated in copper irradiated by helium at room temperature. Large number of the cavities with sizes smaller than 5 nm formed after irradiation, which were almost homogenously distributed inside the grains. However, the distribution of the cavities varied near the general grain boundary and the twin boundary. Cavities-depleted zone was readily observed near the general grain boundaries, which was rarely observed near the twin boundaries. Meanwhile, decoration of dense cavities within the grain boundary plane was observed. The results suggested the limited influence of the twin boundaries as the point defect sinks compared with the general grain boundaries.

关键词： Transmission electron microscopy Cavities Cavities-depleted zone General grainboundary Twin boundary

Electromigration in eutectic SnAg solder reaction couples with various ambient temperatures and current densities

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 685-690页

作者： Guang-chen Xu Fu Guo wan-rong Zhu College of Materials Science and Engineering Beijing University of Technology Beijing 100124 China

The electromigration behavior of eutectic SnAg solder reaction couples was studied at various temperature （25 and 120℃ when the current density was held constant at 104 A/cm^2 or 5×10^3 A/cm^2. Under the current density of 104 A/cm^2, scallop type Cu6Sn5 spalls and migrates towards the direction of electron flow at room ambient temperature （25℃）, but transforms to layer type Cu3Sn and leaves Kirkendall voids in it at high ambient temperature （120℃）. Under the current density of 5×10^3 A/cm^2 plus room ambient temperature, no obvious directional migration of metal atoms/ions is found. Instead, the thermal stress induced by mismatch of dissimilar materials causes the formation of superficial valley at both interfaces. However, when the ambient temperature increases to 120℃, the mobility of metal atoms/ions is enhanced, and then the grains rotate due to the anisotropic property of β-Sn.

关键词： electromigration eutectic solder Joule heating intermetallic compound

Effect of precipitates on high-temperature strength and irradiation behavior of vanadium-based alloys

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Journal of Iron and Steel Research International 2018年第12期25卷 1270-1277页

作者： Shao-ning Jiang Li-qun Xu Fa-rong wan School of Mechanical and Automotive Engineering Qilu University of Technology (Shandong Academy of Science) Jinan 250353ShandongChina School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

The formation of precipitates and their effect on mechanical properties and irradiation damage in V-4CraTi alloys have been investigated using transmission electron microscope,high-temperature tensile tests and high-voltage electron microscope (HVEM).V-4Cr-4Ti alloys were aged for 20-40 h at 873 K,and extremely fine precipitates were produced during the aging process,which coarsened with aging *** results of high-temperature (773,873 and 973 K)tensile tests showed an increase in strength with increasing aging time (i.e:,increasing size of precipitates)while a decrease in the uniform *** was evidence that presence of precipitates strengthened V-4Cr-4Ti *** situ HVEM observations showed that the precipitates restricted the growth rate of dislocation loops induced during electron irradiation at 773 *** interactions between precipitates and irradiation-induced dislocation loops were *** presence of particles alleviated the increase in irradiation hardening up to an irradiation dose of 3.42 dpa (displacement per atom).The precipitates shrank in size during electron irradiation,which was due to the dissolution of constituent atoms of the precipitates into the alloy matrix.

关键词： Aging Precipitate strengthening Electron irradiation Irradiation defect Dislocation loop

Spatial and Seasonal Patterns of Ichthyoplankton Assemblages in the Haizhou Bay and Its Adjacent Waters of China

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Journal of Ocean University of China 2015年第6期14卷 1041-1052页

作者： LI Zengguang YE Zhenjiang wan rong College of Fisheries Ocean University of China Function Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and Technology

Surveys were conducted in five voyages in Haizhou Bay and its adjacent coastal area from March to December 2011 during full moon spring tides. The ichthyoplankton assemblages and the environmental factors that affect their spatial and seasonal patterns were determined. Totally 35 and 12 fish egg and larvae taxa were identified, respectively. Over the past several decades, the egg and larval species composition has significantly changed in Haizhou Bay and its adjacent waters, most likely corresponding with the alteration of fishery resources, which are strongly affected by anthropogenic activities and climate change. The Bray-Curtis dissimilarity index identified four assemblages: near-shore bay assemblage, middle bay assemblage and two closely related assemblages(near-shore/middle bay assemblage and middle/edge of bay assemblage). The primary species of each assemblage principally reflected the spawning strategies of adult fish. The near-shore bay assemblage generally occurred in near-shore bay, with depths measuring <20 m, and the middle bay assemblage generally occurred in the middle of bay, with depths measuring 20 to 40 m. Spatial and seasonal variations in ichthyoplankton in each assemblage were determined by interactions between biological behavioral traits and oceanographic features, particularly the variation of local conditions within the constraint of a general reproductive strategy. The results of Spearman's rank correlation analysis indicated that both fish egg and larval abundance were positively correlated with depth, which is critical to the oceanographic features in Haizhou Bay.

关键词： ichthyoplankton,composition,horizontal patterns,assemblage,Haizhou Bay

Application and Pullback of the Risk- assumption Principle under Special Circumstances

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学术界 2014年第10期 268-272页

作者： Yang Lin wan rong Physical Culture Institute Chongqing University Chongqing 400044 Sub-district Office Huaxin Street of Jiangbei District Chongqing 400020

The risk-assumption principle in infringement is widely used in sport injuries,which is accepted in both the theoretical circle and the juridical practice in China. If the personal injury on the sports ground is not caused by wrongful conducts,the risk-assumption principle is applied,and the doer does not assume compensation liability. If the personal injury is caused by illegality or purposeful illegality to cause personal injury,the risk-assumption principle shall be pulled back totally or partially,and the fault-offset principle and fairly-share-loss principle shall be applied to balance the interests of the two parties. However,under some special circumstances,it is difficult to judge whether there are wrongly conducts; fromthe controversial sports phenomena and sports subjects,this paper analyzes the application and pullback of the risk-assumption principle under some special circumstances.

关键词：风险应用人身伤害运动损伤赔偿责任人身伤亡补偿原则网络连接

Growth and Distribution of Amphioctopus fangsiao(d'Orbigny, 1839–1841) in Haizhou Bay, Yellow Sea

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Journal of Ocean University of China 2020年第5期19卷 1125-1132页

作者： PANG Yumeng TIAN Yongjun FU Caihong REN Yiping wan rong Fisheries College Ocean University of ChinaQingdao 266003China Frontiers Science Center for Deep Ocean Multispheres and Earth System(FDOMES) Ocean University of ChinaQingdao 266100China Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Fisheries and Oceans Canada Pacific Biological StationNanaimoBritish Columbia V9T 6N7Canada College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China

Octopus fisheries have prospered in many areas of the world ocean over the last six decades. Despite degradation and overexploitation of Chinese coastal ecosystems, octopus has become a stable Chinese domestic fishery species. Among the octopus species in the Bohai and Yellow, East and South China Seas, Amphioctopus fangsiao(d'Orbigny [in Férussac & d'Orbigny], 1839–1841) plays an increasingly important role both economically and ecologically. However, no systematic research has been conducted on its biology and population dynamics in the China Seas. In this study, we characterized the growth and distribution of A. fangsiao in Haizhou Bay, Yellow Sea based on four years of trawl survey data. As the results, A. fangsiao is characterized by allometric growth and an overall sex ratio of 0.97 with a slight male bias. Small octopus can be observed through a whole year, suggesting that A. fangsiao may have an extended or continuous spawning season. A. fangsiao may migrate short distances along with seasonal changes and coastal currents, considering they overwinter in the offshore water and spawn in the inshore water. In addition to fishing pressure, annual variations in the population structure and biomass appeared to be influenced by ambient water temperature. These results provide basic biological information for a better understanding of the population dynamics and the ecological importance of A. fangsiao.

关键词： Amphioctopus fangsiao cephalopod Haizhou Bay growth spatial distribution

The Effect of Three Culture Methods on Intensive Culture System of Pacific White Shrimp (Litopenaeus vannamei)

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Journal of Ocean University of China 2013年第3期12卷 434-440页

作者： MA Zhen wan rong SONG Xiefa GAO Lei College of Fisheries Ocean University of China Provincial Key Laboratory of Marine Fishery Molecular Biology of Liaoning Provincial Ocean and Fishery Science Institute of Liaoning

Different culture methods may affect the intensive culture system of Pacific white shrimp(Litopenaeus vannamei) regarding water quality and growth and economic *** study evaluated the potential effects of three culture methods through cultivation of juvenile shrimps under consistent tank management conditions for 84 *** three methods involved shrimp cultivation in different tanks,i.e.,outdoor tanks with cement bottom(mode-C),greenhouse tanks with cement bottom(mode-G) and outdoor tanks with mud-substrate(mode-M).Results showed that water temperature was significantly higher in mode-G than that in mode-C(P 0.05),mode-M had significantly higher shrimp yield,survival rate and feed conversion rate(P < 0.05) than other *** were significant differences in revenue and net return among different treatments(P < 0.05).These demonstrated that the treatments of mode-G and mode-M were conductive to the intensive culture system of ***.

关键词： culture method water quality growth performance economic performance Litopenaeus vannamei

Research progresses of artificial nucleic acid cleavage agents

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Chinese Science Bulletin 2000年第22期45卷 2017-2028页

作者： rong wan Gang Zhao Jing Chen Yufen Zhao Tsinghua Univ Dept Chem State Key Lab Bioorgan Phosphorus Chem Educ Minist ChinaSch Life Sci & Engn Beijing 100084 Peoples R China

Artificial nucleic acid cleavage agents have attracted close attention because they play important roles in biochemistry and molecular biology. According to the cleavage mechanism of nucleic acid, they are divided into three types, namely free radical, phosphodiester bond hydrolysis and elimination cleavage agents. In this review, a series of cleavage agents, including the site- and sequence-specific ones, are illustrated, and some suggestions for the future researches in this field are also put forward.

关键词： nucleic acid cleavage agents site-and sequence-specific cleavage agents free radical phosphodiester bond hydrolysis elimination.