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Aeolian transport over a developing transverse dune

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Journal of Arid Land 2014年第3期6卷 243-254页

作者： ZhiBao DONG Ping lv ZhengCai ZHANG JunFeng LU Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

The spatial and temporal changes in aeolian transport over a dune are fundamental factors that control the morphology of the dune. In the present study, we obtained direct field observations of aeolian transport over a developing transverse dune at the Shapotou Aeolian Experiment Site in the southeastern part of China＇s Tengger Desert. The transport rate versus wind speed relationship relationships over flat surfaces and over dunes that are s complicated over a developing dune compared with the n equilibrium with the wind. We obtained trend lines for transport rate over the transverse dune versus distance. The transport rate generally increased from the toe to the crest above the stoss slope, but the difference in transport rate between the crest and the toe was smaller than those that have been proposed for taller dunes. The crest/toe ratio for transport rates therefore seems to depend greatly on dune height. Flux density profiles for different points above the dune at different wind speeds were well described by the exponential decay law, as has been proposed for saltation flux density profiles. Coefficients in the flux density profile function can be defined in terms of the transport rate and wind speed. However, the dependence of relative decay rate with height and average saltation height on wind speed was weaker than that observed in a wind tunnel and above a fiat surface. The preliminary results obtained in this study require more evidence from field observations to fully describe aeolian transport above developing dunes.

关键词： aeolian transport aeolian geomorphology dune dynamics

Mechanical Properties and Microstructure of 6082-T6 Aluminum Alloy Joints by Self-support Friction Stir Welding

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Journal of Materials Science & Technology 2014年第12期30卷 1243-1250页

作者： Long Wan Yongxian Huang Weiqiang Guo Shixiong lv Jicai Feng State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology

The majority of this research has concentrated on developing the self-support friction stir welding（SSFSW） tool which consists of a big concave upper shoulder and a small convex lower shoulder, and procedures for making reliable welds in aluminum hollow extrusion. The 5-mm-thick 6082-T6 aluminum alloy was self-support friction stir welded at a constant tool rotation speed of 800 r/min. The effect of welding speed on microstructure and mechanical properties was investigated. The results of transverse tensile test indicated that the tensile strength of joints increased and the elongation decreased with increasing welding speed. The whole values of microhardness of SSFSW joints increased with increasing welding speed from 10 to 200 mm/min. The defectfree joints were obtained at lower welding speeds and the tensile fracture was located at the heat-affected zone（HAZ） adjacent to the thermo-mechanically affected zone（TMAZ） on the advancing side. The investigation of the flow pattern of the softened metal around the SSFSW tool revealed that the flow pattern of the softened metal was driven by two shoulders and the stir pin. The failure of specimens in tension presented the ductile fracture mode.

关键词： Self-support friction stir welding Aluminum alloy Welding speed Mechanical properties Microstructure Flow pattern

Bioavailability and tissue distribution of Dechloranes in wild frogs(Rana limnocharis) from an e-waste recycling area in Southeast China

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Journal of Environmental Sciences 2014年第3期26卷 636-642页

作者： Long Li wenyue Wang Quanxia lv Yujie Ben Xinghong Li State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center of Eco-Environment SciencesChinese Academy of Sciences

Dechlorane Plus （DP）,a flame retardant used as an alternative to decabromodiphenylether, has been frequently detected in organisms, indicating its bioaccumulation and biomagnification potential in aquatic and terrestrial species. However, little data is available on the bioaccumulation of DP in amphibians. Dechlorane Plus and its analogs （DPs） were detected in the liver, muscle and brain tissues of wild frogs （Rana limnocharis）, which were collected from an e-waste recycling site, Southeast China. DP, Mirex, Dec 602 and a dechlorinated compound of DP （anti-Cll I-DP） varied in the range of 2.01-291, 0.650-179, 0.260-12.4, and not detected （nd）-8.67 ng/g lipid weight, respectively. No difference of tissue distribution was found for syn-DP, Mirex and Dec 602 between the liver and muscle tissue （liver/muscle concentration ratio close to 1, p 〉 0.05）. However, higher retention was observed for anti-DP and anti-Cll1-DP in the frog muscle relative to the liver tissue （liver/muscle concentration ratio 〈 1, p 〈 0.05）. Additionally, the blood-brain barrier was found to work efficiently to suppress these compounds entering brain tissues in this species （liver/brain concentration ratio 〉 l, p 〈 0.05）, and the molecular weight was a key factor impacting the extent of the blood-brain barrier. Compared to levels in the muscle and brain tissue, a preferential enrichment of syn-DP was observed in the liver tissue, suggesting the occurrence of stereo-selective bioaccumulation in the wild frog.

关键词： dechlorane plus and its analogs e-waste wild frogs

An effective method for service components selection based on micro-canonical annealing considering dependability assurance

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Frontiers of Computer Science 2019年第2期13卷 264-279页

作者： Shichen ZOU Junyu LIN Huiqiang WANG Hongwu lv Guangsheng FENG College of Computer Science and Technology Harbin Engineering University Harbin 150001 China Institute of Information Engineering Chinese Academy of Sciences Beijing 100093 China Department of Electrical and Computer Engineering University of Victoria Victoria V8W 3P6 Canada

Distributed virtualization changes the pattern of building software systems. However, it brings some problems on dependability assurance owing to the complex social relationships and interactions between service components. The best way to solve the problems in a distributed virtualized environment is dependable service components selection. Dependable service components selection can be modeled as finding a dependable service path, which is a multiconstrained optimal path problem. In this paper, a service components selection method that searches for the dependable service path in a distributed virtualized environment is proposed from the perspective of dependability assurance. The concept of Quality of Dependability is introduced to describe and constrain software system dependability during dynamic composition. Then, we model the dependable service components selection as a multiconstrained optimal path problem, and apply the Adaptive Bonus-Penalty Microcanonical Annealing algorithm to find the optimal dependable service path. The experimental results show that the proposed algorithm has high search success rate and quick converges.

关键词： service components selection dependability assurance distributed virtualization microcanonical annealing

Numerical simulation of preparation of ultrafine cerium oxides using jet-flow pyrolysis

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Rare Metals 2019年第12期38卷 1160-1168页

作者： Chao lv Ting-An Zhang Zhi-He Dou Qiu-Yue Zhao Key Laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Ministry of Education Special Metallurgy and Process Engineering InstituteNortheastern UniversityShenyang 110819China School of Control Engineering Northeastern University at QinhuangdaoQinhuangdao 066004China

Ultrafine rare-earth oxides(REOs) are widely applied in all fields of daily life,but the conventional preparation methods are limited by a long procedure,low efficiency and severe environmental *** team has independently developed a jet pyrolysis reactor for the preparation of ultrafine cerium oxides,and this process has theoretical significance and practical application *** this study,gas-solid pyrolysis reactions inside the jet-flow pyrolysis reactor were numerically *** performed a coupling computation of the combustion,phase transformation and gas-solid reaction on Fluent and userdefined *** characterized the flows of different phases as well as the compositions and distributive laws of the reactants/products in the *** gas-phase inlet velocity and dynamic pressure/additional pressure were related by a quadratic *** velocity at the throat inlet changed the most,and the outlet velocity was very *** CeO2 concentrations were obviously *** study enriches theories of jet-flow pyrolysis and theoretically underlies the optimization and popularization of self-developed pyrolysis reactors.

关键词： Jet-flow Pyrolysis Reactor Cerium oxides Numerical simulation

Design Method of Equipment Optimization Development Based on Standardization Theory

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Defence Technology（防务技术） 2013年第3期9卷 140-145页

作者： lv-bo MAI China North Standardization Research Center

The matters of equipment optimization development are usually discrete,fuzzy and *** is difficult directly to optimize the equipment development with a mathematical model.A set of methods for designing the equipment optimization development with six dimensions and eight main elements is established based on the theory and method of *** top-tier design space of systematic development of equipment is built up by the relations of basic models,series and model *** relations of time and space for equipment optimization development are *** design processes of a six dimension systematic space are *** connotation of each plan in the main system space is analyzed.A design method for an entire equipment is established with standardization *** coordinating design methods of equipment technical system and the optimization design methods of equipment integration are *** design methods for universalization and serialization of components and parts are *** design methods of equipment optimization development highlight the relations of the basic model of platform,the serialization of platform basic models,the modularization of equipment functions,the model spectrum of variant equipment,and the universalization and serialization of components and parts.

关键词：优化设计方法优化开发化设备标准化优化发展数学模型设计空间设备系统

西方体育全球化背景下中国武术的现代危机与传统再造

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山东体育学院学报 2020年第1期36卷 42-47页

作者：李文鸿吕思泓嘉应学院广东梅州514015

因包含着同一性和异质性的两个面向,西方体育的全球化对中国武术而言既是挑战又是机遇,中国武术需要在对自身的检视中确立传统再造的基本思路。中国武术现代危机成因有三:其一,作为“传统”的中国武术遭遇“有机团结”的现代社会必然不... 详细信息

因包含着同一性和异质性的两个面向,西方体育的全球化对中国武术而言既是挑战又是机遇,中国武术需要在对自身的检视中确立传统再造的基本思路。中国武术现代危机成因有三:其一,作为“传统”的中国武术遭遇“有机团结”的现代社会必然不适;其二,武术非游戏的特质以及突出的底层性决定了它的“非现代性”;其三,民族主义的文化保守及机械附庸西方的标准化使其陷入两个极端。为此,正视武术不可化约为外来体育的独特性,继而在武术文化认同的形塑中,正确处理武术发展社会模式构成多元角色的关系,同时在新型城乡关系中厚植武术文化生态根基,是中国武术传统再造的可行思路。

关键词：中国武术西方体育全球化现代化传统再造

MOBILE PHONE AS PERVASIVE ELECTRONIC MEDIA TO RECORD AND EVALUATE HUMAN GAIT BEHAVIOR

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Journal of Innovative Optical Health Sciences 2012年第1期5卷 28-35页

作者： QIAN WANG YANG YU YONGQIANG lv JING LIU Department of Biomedical Engineering School of Medicine Tsinghua UniversityBeijing 100084P.R.China Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 P.R.China

Gait recognition has been of great importance for disease diagnosis,rehabilitation assessment,as well as personal *** gait analysis generally has to rely heavily on complex,expensive data acquisition and computing *** significantly simplify the evaluation process the mobile phone,which is one of the most indispensable electronic media in human daily life,was adopted as a pervasive tool for gait study,by using its digital imaging recording and analysis *** basic procedure to record and quantify the video of human gait was illustrated and demonstrated through conceptual *** applications were *** fundamental and practical issues raised in such flexible technology were pointed *** method is expected to be widely used in future human analysis.

关键词： Gait analysis telemedicine pervasive medicine low cost medicine

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干辣椒中二氧化硫残留量的快速检测

食品与发酵科技 2024年第3期60卷 124-128页

作者：王志宏郭晓艳朱万燕王猛罗晓吕斐刘冲伟龙口海关龙口265700 临沂海关临沂276000 龙口检验认证有限公司龙口265700

针对GB 5009.34—2022《食品安全国家标准食品中二氧化硫的测定》在检测干辣椒中二氧化硫时,存在耗时长问题,本研究重点优化了前处理方式,并建立了非通氮的全自动蒸馏离子色谱法,用于快速分析测定干辣椒中二氧化硫含量,从而大大缩短了... 详细信息

针对GB 5009.34—2022《食品安全国家标准食品中二氧化硫的测定》在检测干辣椒中二氧化硫时,存在耗时长问题,本研究重点优化了前处理方式,并建立了非通氮的全自动蒸馏离子色谱法,用于快速分析测定干辣椒中二氧化硫含量,从而大大缩短了检测时间。样品酸化产生的二氧化硫气体经微量蒸馏仪快速蒸出,被氢氧化钠溶液吸收生成稳定的亚硫酸盐,经滤膜过滤后进离子色谱仪测定。结果表明,亚硫酸根在1.0~100mg/L浓度范围内呈良好的线性关系,相关系数为0.9992,方法检出限为1.0mg/kg。加标平均回收率为87.8%~106.0%,相对标准偏差(RSD)为1.57%~1.82%。该方法适合大批量干辣椒样品中二氧化硫的快速、准确检测。

关键词：干辣椒二氧化硫残留量快速检测