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Gender of large river deltas and parasitizing rivers

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International Journal of Sediment Research 2012年第1期27卷 18-36页

作者： Zhao-yin wang Guo-an YU He qing HUANG Rui-yu wang State Key Laboratory of Hydro-Science and Engineering Tsinghua University University of Illinois at Champain and Urbana Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Chairman of the Advisory Council of UNESCO International Research and Training Center on Erosion and Sedimentation

Deltas are the most dynamic part of large rivers and the characteristics of deltas reflect the basic nature of morphodynamics,ecology and anthropogenic *** authors investigated many deltas of large rivers,including the Yellow,Yangtze,Pearl,Rhine,Nile,Mississippi,Luanhe and Ebro *** were collected and sediment,water,benthic invertebrates and fish were sampled. Statistical analysis showed that deltas can be classified into male deltas and female *** deltas of the Yellow,Mississippi,Luanhe,Ural and Ebro rivers are male *** deltas extend into the ocean,each with only one or two channels,forming a *** development process is accompanied with periodic nodal or random *** deltas develop if the sediment load/water ratio is high and the tidal range is *** deltas of the Yangtze,Rhein-Meuse-Scheldt,Pearl and Irrawaddy rivers are *** deltas consist of complex channel networks and numerous bars and *** deltas develop if the load/water ratio is not high and tidal current is relatively *** deltas provide stable and multiple habitats for various ***,the biodiversity of female deltas and the taxa richness of benthic invertebrates and fish are much higher than that of male *** activities reduced sediment load and change the delta gender from male to *** rivers have high levees in their lower reaches and *** rivers originate from the levees of a male river and flow parallel with the river into the ***, persistence,length and stability of these rivers depend on the male river to which they are attached. Therefore,these rivers are named parasitizing *** general,parasitizing rivers have no tributaries and almost no drainage *** runoff of these rivers comes from the rainfall on the surrounding area,and therefore,the flow discharge exhibits very sharp peaks during *** Yellow and Luanhe rivers have many parasitizing rivers.

关键词： Classification of deltas Male and female rivers Morphology River patterns Parasitizing river Yellow River

Experimental and numerical investigation of the influence of roughness and turbulence on LUT airfoil performance

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Acta Mechanica sinica 2019年第6期35卷 1178-1190页

作者： Shoutu Li Ye Li Congxin Yang Xiaobo Zheng qing wang Yin wang Deshun Li Wenrui Hu School of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China Gansu Provincial Technology Centre for Wind Turbines Lanzhou 730050China Key Laboratory of Fluid Machinery and Systems Lanzhou 730050China Lab of Multiple Function Towing Tank School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Ocean Engineering School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Hydrodynamics(Ministry of Education) Shanghai Jiao Tong UniversityShanghai 200240China Institute of Mechanics Chinese Academy of SciencesBeijing 100080China

Vertical-axis wind turbines(VAWTs)have been widely used in urban environments,which contain dust and experience strong ***,airfoils for VAWTs in urban environments have received considerably less research attention than those for horizontal-axis wind turbines(HAWTs).In this study,the sensitivity of a new VAWT airfoil developed at the Lanzhou University of Technology(LUT)to roughness was investigated via a wind tunnel *** results show that the LUT airfoil is less sensitive to roughness at a roughness height ofsing roughness ***,the loads on the LUT airfoil during dynamic stall were studied at different turbulence intensities using a numerical method at a tip-speed ratio of *** the stall,the turbulence intensity did not considerably affect the normal or tangential force coefficients of the LUT ***,after the stall,the normal force coefficient varied obviously at low turbulence ***,as the turbulence intensity increased,the normal and tangential force coefficients decreased rapidly,particularly in the downwind region of the VAWT.

关键词： Airfoil Dynamic load Roughness Vertical-axis wind turbines(VAWTs) Wind tunnel experiment

Purification of copper foils driven by single crystallization

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Chinese Physics B 2024年第2期33卷 506-511页

作者：寇金宗赵孟泽李兴光何梦林杨方友刘科海成庆秋任云龙刘灿付莹吴慕鸿刘开辉王恩哥 Songshan Lake Materials Laboratory Dongguan 523808China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of PhysicsSouth China Normal UniversityGuangzhou 510006China Guangdong–Hong Kong Joint Laboratory of Quantum Matter Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China State Key Laboratory for Mesoscopic Physics Frontiers Science Center for Nano-optoelectronicsSchool of PhysicsPeking UniversityBeijing 100871China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Department of PhysicsRenmin University of ChinaBeijing 100872China International Center for Quantum Materials Collaborative Innovation Center of Quantum MatterPeking UniversityBeijing 100871China School of Physics Liaoning UniversityShenyang 110036China

High-purity copper(Cu) with excellent thermal and electrical conductivity, is crucial in modern technological applications, including heat exchangers, integrated circuits, and superconducting magnets. The current purification process is mainly based on the zone/electrolytic refining or anion exchange, however, which excessively relies on specific integrated equipment with ultra-high vacuum or chemical solution environment, and is also bothered by external contaminants and energy consumption. Here we report a simple approach to purify the Cu foils from 99.9%(3N) to 99.99%(4N) by a temperature-gradient thermal annealing technique, accompanied by the kinetic evolution of single crystallization of *** success of purification mainly relies on(i) the segregation of elements with low effective distribution coefficient driven by grain-boundary movements and(ii) the high-temperature evaporation of elements with high saturated vapor *** purified Cu foils display higher flexibility(elongation of 70%) and electrical conductivity(104% IACS) than that of the original commercial rolled Cu foils(elongation of 10%, electrical conductivity of ~ 100% IACS). Our results provide an effective strategy to optimize the as-produced metal medium, and therefore will facilitate the potential applications of Cu foils in precision electronic products and high-frequency printed circuit boards.

关键词： purification copper foil thermal annealing technique single crystallization

simultaneous anti-windup synthesis for linear systems subject to actuator saturation

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Journal of Systems Engineering and Electronics 2015年第1期26卷 119-126页

作者： Maopeng Ran qing wang Chaoyang Dong Maolin Ni School of Automation Science and Electrical Engineering Beihang University School of Aeronautic Science and Engineering Beihang University Chinese Society of Astronautics

A synthesis method for global stability and performance of input constrained linear systems, which uses a linear outputfeedback controller and a static anti-windup compensator is investigated. Different from the traditional two-step anti-windup design procedure, the proposed method synthesizes all controller parameters simultaneously. Sufficient conditions for global stability and minimizing the induced L2 gain are formulated and solved as a linear matrix inequalities（LMIs） optimization problem, which also provides an opportunity to search for a better performance tradeoff between the linear controller and the anti-windup *** well-posedness of the close-loop system is also *** results show the effectiveness of the proposed method.

关键词： actuator saturation anti-windup simultaneous synthesis L2 synthesis linear matrix inequalities(LMIs)

罗沙司他对血液透析肾性贫血患者血液生化指标的影响及成本效果探究

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中国处方药 2024年第4期22卷 121-123页

作者：王欢钟燕玲杨庆祥龙川县人民医院血液净化中心广东河源517300

目的探讨罗沙司他对血液透析肾性贫血患者的影响。方法取2021年7月~2022年12月龙川县人民医院血液透析肾性贫血患者80例,以随机数表法分为两组,各40例;对照组重组人促红素注射液治疗,观察组罗沙司他治疗。对比治疗效果、不良反应发生率... 详细信息

目的探讨罗沙司他对血液透析肾性贫血患者的影响。方法取2021年7月~2022年12月龙川县人民医院血液透析肾性贫血患者80例,以随机数表法分为两组,各40例;对照组重组人促红素注射液治疗,观察组罗沙司他治疗。对比治疗效果、不良反应发生率、成本,测定血液生化指标[血红蛋白(Hb)、血细胞比容(HCT)和促红细胞生成素(EPO)]水平,全自动生化分析仪检测铁代谢指标[转铁蛋白(TRF)、铁蛋白(FER)]水平。结果观察组治疗有效率87.50%(35/40)高于对照组67.50%(27/40)(P<0.05);治疗后,两组患者Hb、HCT、EPO水平升高,且观察组水平较高(P<0.05);治疗后,两组患者TRF水平升高,且观察组水平较高,两组FER水平降低,且观察组水平较低(P<0.05);观察组治疗成本高于对照组(P<0.05);观察组不良反应发生率7.50%低于对照组25.00%(P<0.05)。结论罗沙司他对血液透析患者肾性贫血虽成本较高,但其效果较好,能够改善患者的贫血情况,促进铁代谢,且安全性较高。

关键词：罗沙司他血液透析肾性贫血铁代谢血红蛋白

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泡沫轻质土路基浇筑体质量试验研究

公路 2024年第1期69卷 9-15页

作者：孙傲熊先勇王晓霞徐清政姜峰林湖南路桥建设集团有限责任公司长沙市410018 广东首诚建设科技有限公司广州市514110

泡沫轻质土浇筑体是含有微裂缝、收缩裂缝、推挤分层、融合消泡等缺陷的水泥基材料。采用钻芯法和轻型圆锥动力触探法对泡沫轻质土浇筑体的质量进行了尝试性试验,以期验证两种方法对浇筑体进行质量检验的可行性和可靠性。结果表明,泡沫... 详细信息

泡沫轻质土浇筑体是含有微裂缝、收缩裂缝、推挤分层、融合消泡等缺陷的水泥基材料。采用钻芯法和轻型圆锥动力触探法对泡沫轻质土浇筑体的质量进行了尝试性试验,以期验证两种方法对浇筑体进行质量检验的可行性和可靠性。结果表明,泡沫轻质土在按施工要求浇筑的前提下,钻芯法所取芯样光滑完整,无侧限抗压强度离散性小,可直接表征实际浇筑质量;通过贯入击数的变化可以直接判定浇筑体的均匀性,贯入30 cm深度的击数与对应的无侧限抗压强度具有良好的线性关系,通过回归公式可预测浇筑体的抗压强度。

关键词：路基工程泡沫轻质土浇筑体质量评测无侧限抗压强度圆锥动力触探

New measuring method of fiber alignment in precision torsion pendulum experiments

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Chinese Physics B 2020年第8期29卷 162-167页

作者： Bing-Jie wang Li Xu Wei-You Zeng qing-Lan wang College of Science Hubei University of Automotive and TechnologyShiyan 442002China

Testing the extreme weak gravitational forces between torsion pendulum and surrounding objects will indicate new physics which attracts many *** these measurements,the fiber alignment plays a crucial role in fulfilling high precision placement measurement,especially in measuring the deviation between the fiber and source mass or other *** traditional way of the fiber alignment requires to measure the component of the pendulum body and then transfer to the torsion fiber by some complicated calculations.A new method is reported here by using a CCD camera to get the projection image of the torsion fiber,which is a direct and no-contact ***,the relative position change of the torsion fiber can also be monitored during the *** our experiment,the alignment between the fiber and the center of the turntable has been operated as an *** result reaches the accuracy of several micrometers which is higher than the previous method.

关键词： torsion pendulum alignment CCD camera

Dynamically tunable multiband plasmon-induced transparency effect based on graphene nanoribbon waveguide coupled with rectangle cavities system

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Chinese Physics B 2022年第8期31卷 440-452页

作者： Zi-Hao Zhu Bo-Yun wang Xiang Yan Yang Liu qing-Dong Zeng Tao wang Hua-qing Yu School of Physics and Electronic-information Engineering Hubei Engineering UniversityXiaogan 432000China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

A dynamically tunable multiband plasmon-induced transparency(PIT) effect in a series of rectangle cavities coupled with a graphene nanoribbon waveguide system is investigated theoretically and numerically by tuning the Fermi level of the graphene rectangle cavity. A single-PIT effect is realized using two different methods: one is the direct destructive interference between bright and dark modes, and the other is the indirect coupling through a graphene nanoribbon waveguide. Moreover, dual-PIT effect is obtained by three rectangle cavities side-coupled with a graphene nanoribbon *** show that the magnitude of the dual-PIT window can be controlled between 0.21 and 0.74, and the corresponding group index is controlled between 143.2 and 108.6. Furthermore, the triple-PIT effect is achieved by the combination of bright–dark mode coupling and the cavities side-coupled with waveguide mechanism. Thus, sharp PIT windows can be formed, a high transmission is maintained between 0.51 and 0.74, and the corresponding group index is controlled between161.4 and 115.8. Compared with previously proposed graphene-based PIT effects, the size of the introduced structure is less than 0.5 μm2. Particularly, the slow light effect is crucial in the current research. Therefore, a novel approach is introduced toward the realization of optical sensors, optical filters, and slow light and light storage devices with ultra-compact,multiband, and dynamic tunable.

关键词： plasmon-induced transparency(PIT) graphene group index rectangle cavities

Quenched-in liquid in glass

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Materials Futures 2023年第1期2卷 168-172页

作者： qing wang Ying-Hui Shang Yong Yang Laboratory for Microstructures Institute of MaterialsShanghai UniversityShanghai 200072People’s Republic of China Department of Mechanical Engineering College of EngineeringCity University of Hong KongKowloon TongKowloonHong KongPeople’s Republic of China Department of Materials Science and Engineering College of EngineeringCity University of Hong KongKowloon TongKowloonHong KongPeople’s Republic of China Department of Advanced Design and System Engineering College of EngineeringCity University of Hong KongKowloon TongKowloonHong KongPeople’s Republic of China

Glasses have long been considered as frozen liquids because of the similarity between their static amorphous *** the modern theories about glass transition suggest that glass transition may result from supercooling of a heterogeneous liquid that contains fast and slow regions,it remains unclear whether such a physical picture applies to metallic glasses,which are a densely packed solid glass that was once believed to be a vitrified homogeneous metallic ***,in the recent work published in Nature Materials,Chang et al provide compelling evidence to show that metallic glasses contain liquid-like atoms that behave as a high-temperature liquid in stress *** activated under cyclic loading,this quenched-in liquid results in a fast relaxation process,which is discovered in a variety of metallic *** results are important and deliver a strong message that metallic glasses have a dynamic microstructure containing liquid-and solid-like *** importantly,the outcome of their research provides physical insight into the nature of glass-transition in metallic glasses,and also helps unravel their structure-property relations.

关键词： glass transition metallic glasses structural heterogeneity structure-property relation