Flume experiments and numerical simulation were conducted to characterize the hydrodynamics of a trapezoid artificial reef.Measurements in particle image velocimetry were conducted to observe the formation of upwellin...Flume experiments and numerical simulation were conducted to characterize the hydrodynamics of a trapezoid artificial reef.Measurements in particle image velocimetry were conducted to observe the formation of upwelling and vortices;and forces for the reef model were measured by load cell.The results of flume experiments agree well with the numerical data.In addition,the flow structure around a reef combining trapezoidal and cubic blocks was simulated numerically under two deployment schemes,showing a more complicated flow structure than that of a stand-alone reef.Relationship between drag coefficient and Reynolds number suggest that the degree of turbulence can be assessed from the value of drag coefficient downstream from the reef.The role of the reef in water flow is to reduce flow velocity and generate turbulence.展开更多
Here we describe tHuashancyprinus robustispinus, gen. et sp. nov, a fossil cyprinin fish from the Oligocene of Ningming Ba- sin, Guangxi, South China. It differs from all other cyprinin fishes in the following apomorp...Here we describe tHuashancyprinus robustispinus, gen. et sp. nov, a fossil cyprinin fish from the Oligocene of Ningming Ba- sin, Guangxi, South China. It differs from all other cyprinin fishes in the following apomorphic characters: extremely robust last unbranched dorsal and anal fin rays with very fine serrations along posterior edge, the crowns of pharyngeal teeth A2 and A3 with a number of deep grooves on the lateral wall, rather large A3, and relatively deep infraorbital 2. Among the members of the Tribe Cyprinini sensu stricto, it mostly resembles the extant genus Cyprinus, particularly to species Cyprinus micristius and C. fuxianensis, which are restricted to Yunnan, southwestern China. The discovery of the cyprinin Huashancyprinus from southern China, along with the previously known late Eocene tCyprinus maomingensis, indicates an early branching of the Cyprininae (Cyprinidae) in this area.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.31072246,31272703)
文摘Flume experiments and numerical simulation were conducted to characterize the hydrodynamics of a trapezoid artificial reef.Measurements in particle image velocimetry were conducted to observe the formation of upwelling and vortices;and forces for the reef model were measured by load cell.The results of flume experiments agree well with the numerical data.In addition,the flow structure around a reef combining trapezoidal and cubic blocks was simulated numerically under two deployment schemes,showing a more complicated flow structure than that of a stand-alone reef.Relationship between drag coefficient and Reynolds number suggest that the degree of turbulence can be assessed from the value of drag coefficient downstream from the reef.The role of the reef in water flow is to reduce flow velocity and generate turbulence.
基金supported by National Natural Science Foundation of China(Grant Nos.40432003 and 40662001)State Key Laboratory of Palaeobiology and Stratigraphy(Nanjing Institute of Geology and Palaeontology,CAS)(Grant No.063106)Cypriniformes Tree of life under the U.S.National Science Foundation to R.Mayden(Grant No. EFO431326),and the Culture Department of Guangxi Zhuang Autonomous Region
文摘Here we describe tHuashancyprinus robustispinus, gen. et sp. nov, a fossil cyprinin fish from the Oligocene of Ningming Ba- sin, Guangxi, South China. It differs from all other cyprinin fishes in the following apomorphic characters: extremely robust last unbranched dorsal and anal fin rays with very fine serrations along posterior edge, the crowns of pharyngeal teeth A2 and A3 with a number of deep grooves on the lateral wall, rather large A3, and relatively deep infraorbital 2. Among the members of the Tribe Cyprinini sensu stricto, it mostly resembles the extant genus Cyprinus, particularly to species Cyprinus micristius and C. fuxianensis, which are restricted to Yunnan, southwestern China. The discovery of the cyprinin Huashancyprinus from southern China, along with the previously known late Eocene tCyprinus maomingensis, indicates an early branching of the Cyprininae (Cyprinidae) in this area.