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| 1 | Records of the East Asian winter monsoon from the mud area on the inner shelf of the East China Sea since the mid-Holocene显示文摘AMS14C dating and analysis of grain size,major elements and clay minerals were applied to Core MZ01 from the mud area on the inner shelf of the East China Sea.Based on the environmentally sensitive grain size,clay mineral and major element assemblages,the history of the East Asia winter monsoon since the mid-Holocene could be reconstructed.These three proxies,mean grain size(>9.71μm),chemical index of alteration(CIA)and ratio of smectite to kaolinite in particular,show similar fluctuation patterns. Furthermore,10 extreme values corresponding to the contemporary cooling events could be recognized since the mid-Holocene;these extreme values are likely to have been caused by the strengthening of the East Asia winter monsoon.The cooling events correlated well with the results of theδ18O curves of the Dunde ice core and GISP2,which therefore revealed a regional response to global climate change.Four stages of the East Asia winter monsoon were identified,i.e.8300-6300 a BP,strong and unstable;6300-3800 a BP,strong but stable;3800-1400 a BP,weak and unstable;after 1400 a BP,weak but stable. | LIU ShengFa SHI XueFa LIU YanGuang QIAO ShuQing YANG Gang FANG XiSheng WU YongHua LI ChaoXin LI XiaoYan ZHU AiMei GAO JingJing | 2010 | Chinese Science Bulletin2010，55，21： | 25 |
| 2 | Field measurements of settling velocities of fine sediments in Three Gorges Reservoir using ADV显示文摘The Three Gorges Reservoir(TGR) is suffering from unexpected fine sediment deposition,to better understand the fine sediment transport processes,field measurements were conducted at the Zhongxian and Fengjie reaches.A method based on the sediment diffusion equation was proposed to measure the settling velocities using the Acoustic Doppler Velocimeter(ADV).The backscatter acoustic intensities(BSI) received from the ADV were calibrated against the sediment concentrations measured via water sampling,suggesting a linear relationship in double logarithmic coordinate system.The instantaneous sediment concentration was calculated using the derived relationship,and then the settling velocity was obtained through the proposed procedure.The settling velocities of the fine particles in the TGR were found to vary with the water depth.Most of the effective settling velocities were within the range of 0.1-10 mm/s,which were larger than those of the primary particles,indicating that the flocculation was likely to occur in the TGR.Additionally,it is suggested that the turbulent motion played an important role in the flocculation in the TGR. | Wenjie Li Shengfa Yang Jiang Hu Xuhui Fu Peng Zhang | 2016 | International Journal of Sediment Research2016，31，3： | 6 |
| 3 | Distribution of major and trace elements in surface sediments of Hangzhou Bay in China显示文摘The Inductively Coupled Plasma Optical Emission Spectrometer was used to analyze sediment samples collected from the Hangzhou Bay to determine major and trace elemental concentrations. Based on these concentrations, the study area can be classified into three geochemical provinces. Province I covers the northern Hangzhou Bay area and contains high concentrations of Al_2 O_3 , Fe_2 O_3 , MgO, Na_2 O, K_2 O, MnO, Cr, Cu, Ni, Pb, V, Co and Zn. Province III is located in the western Hangzhou Bay, near the Qiantang River mouth, and contains high concentrations of SiO_2 , Na_2 O, P_2 O_5 , TiO_2 , Cr, Sr, Zr. Province II is located in the middle and eastern Hangzhou Bay, with the medium concentrations of major and trace elements. The results also demonstrate that the grain size is the dominating factor controlling the spatial variations of elemental concentrations, and the Changjiang River (Yangtze River) and Qiantang River sediments play an important role in the distribution of these elements. Anthropogenic impact on heavy metal concentrations (especially Cr, Sr and Zr) can be detected in the surface sediments near the Qiantang River mouth. | LIU Shengfa LIU Yanguang YANG Gang QIAO Shuqing LI Chaoxin ZHU Zhiwei SHI Xuefa | 2012 | Acta Oceanologica Sinica2012，31，4： | 5 |
| 4 | Experimental investigation on propagating characteristics of sinusoidal unsteady flow in open-channel with smooth bed显示文摘A high accuracy experimental system has been established for unsteady open-channel flow.Then 40 experiments were conducted to study the propagating characteristics of unsteady open-channel flow.From the experimental data,the variation law of propagating velocity,wave deformation rate,flow depth of wave peak and bottom,and other parameters were obtained.The experimental results show the followings.1) The propagating velocity of unsteady open-channel flows can be expressed by the sum of flow velocity and micro-amplitude wave velocity at wave peak.2) The waveform of an unsteady flow would deform when it propagates,with the rising stage becoming longer and the falling stage shorter;the deformation rate is a function of distance,period and relative amplitude of discharge.3) The flow depths of wave peak and bottom have a close relationship with the period of the unsteady flow.When the period is short,water depths of wave peak and bottom are both close to those of the average discharge in the condition of uniform flow.For a long period unsteady flow,the water depth of wave peak is close to that of the maximal discharge in the condition of uniform flow,while at the flow wave bottom,it is close to the depth of the minimum discharge in an uniform flow.4) Propagating characteristic of discharge is analogous to that of flow depth for unsteady flow. | HU Jiang YANG ShengFa FU XuHui | 2012 | Science China(Technological Sciences)2012，55，7： | 4 |
| 5 | Characteristics of the Flow and Sediment in the Inner Rivers' Broad-shallow Shifting Reach显示文摘Rivers are classified into two types.One is the outer river which flows into ocean and the other is the inner river which does not flow into the ocean but into desert or lake.The inner rivers are the erosive rivers that have been seldom studied so far.Based on the field survey data,the analysis on the characteristics of the flow and sediment in the inner rivers' broad-shallow shifting (IRBS) reach.The IRBS reach often bears such the properties as:high gradient bed,usually 10‰or greater;small flow dischar... | Yang, Shengfa Zhou, Huajun Fang, Duo | 2005 | 四川大学学报(工程科学版)2005，37，S1： | 4 |
| 6 | Environmental record from the mud area on the inner continental shelf of the East China Sea since the mid-Holocene显示文摘Paleoclimate record was revealed in Core MZ01 covering the mid-Holocene in age,located in the mud area of the inner continental shelf of the East China Sea. The ancient environment featured low-energy shallow sea shelf deposition formed mainly by coastal currents. The results show that temporal variation in geochemistry corresponds with the climate changes inferred from historical record. Relatively low MgO/Al 2 O 3,CaO/K 2 O and high Al 2 O 3 /Na 2 O,K 2 O/Na 2 O,MnO/CaO values reflected a warm and humid climate in general,and vice versa. Therefore,these chemical indices could be applied to identify the variation of palaeoclimate in eastern China. The authors reconstructed the history of mid-Holocene climatic variation of the inner continental shelf of the East China Sea. From 8 300 a BP to 4 200 a BP,the climate was moderately warm and humid. From 4 200 a BP to 2 000 a BP,the climate turned cool and dry,and the regional climate frequently fluctuated in alternation of cool-dry periods(3 700 a BP,2 850 a BP and 2 400 a BP) and warm-wet periods(3 250 a BP and 2 650 a BP) . After 2 000 a BP,the climate of the study area gradually turned warm again,while the Little Ice Age,a cold event centered at around 250 a BP was indicated by those geochemical indices as mentioned above. | LIU Shengfa SHI Xuefa LIU Yanguang WU Yonghua YANG Gang | 2011 | Acta Oceanologica Sinica2011，30，4： | 3 |
| 7 | INCIPIENT MOTION OF COARSE PARTICLES IN HIGH GRADIENT RIVERS显示文摘In Northwest China, there are many inland rivers that are characterized by high a gradient, coarse particles, a thick pebble and gravel layer, and small discharge and shallow water depth during the flood season. In these rivers, the motion of coarse particles has an important influence on the construction of various structures related to these rivers. In this study, the law of the motion of coarse particles is investigated in high gradient rivers. First, according to the rolling mode of particle motion, the forces acting on coarse particles were analyzed, and a formula was deduced to represent the incipient drag force for uniform coarse particles in a high gradient river. The flow velocity near the river bed, resistance coefficient, and weight of a coarse particle were taken into account to obtain the formula, which indicated that the incipient drag force is not related to the sediment Reynolds number, but closely related to the Froude number, which was also true for the Maxwell formula. Next, after comparing the various criteria for incipient motion of sediment, experiments were done to obtain data and determine the incipient motion of coarse particles. Based on the experiments, it was concluded that the motion type of “embedded” coarse material belongs to the motion of contact load, and the nondimensional unit-width sediment transport rate, which was put forward by Taylor in 1971, was chosen as the criterion in this study. Finally, based on the experimental data, the drag force formula was calibrated. The computed drag force agreed well with the measured values. Moreover, the formula derived in this study was compared with the Maxwell formula, another formula to study the incipient motion of particles in step-shaped mountainous rivers. The comparison indicates that the slope is the key factor in the two formulas, and the weight is an important force on the incipient motion of coarse particles in the current formula, but not in the Maxwell formula. | Shengfa YANG Jiang HU Xingkui WANG | 2006 | International Journal of Sediment Research2006，21，3： | 2 |
| 8 | Estimating instantaneous concentration of suspended sediment using acoustic backscatter from an ADV显示文摘The measurement of instantaneous sediment concentration remains a challenging task. In this study, a three-step procedure is proposed to estimate instantaneous sediment concentration using acoustic backscatter from Acoustic Doppler Velocimeter (ADV). The influences of acoustic noise and particle diameter on an ADV's performance was first tested in the laboratory, then the three-step procedure was verified based on field measurements in the Zhongxian and Fengjie reaches in the Three Gorges Reservoir. The first step involves reconstructing the backscatter signal time series. Due to contamination from both the noise floor and spurious spikes, the denoising-despiking method was applied instead of the traditional velocity-despiking methods, and this approach performed well based on spectrum ana-lysis. The second step involves calibrating the sediment concentration against the backscatter signal. A linear relation, whose slope and intercept were calibrated to be dependent on particle diameter, is proposed in double logarithmic coordinates. The third step involves calculating the instantaneous sediment concentration using reconstructed instantaneous backscatter based on the proposed relation. The accuracy of the proposed method was evaluated through consideration of the concentration spec-trum and sediment flux, indicating that the proposed three-step procedure is effective for the mea-surement of instantaneous sediment concentration. | Wenjie Li Shengfa Yang Wei Yang Yi Xiao Xuhui Fu Shuaishuai Zhang | 2019 | International Journal of Sediment Research2019，34，5： | 2 |
| 9 | Finite element analysis of the electromagnetic field of untouched permanent induction magnetic coupling显示文摘 | Yang Chaojun Wang Yuning Jiang Shengfa | 2006 | Materials Science Forum2006，，： | 1 |
| 10 | Effect of Changjiang Chongqing Dashaba sand excavation on channel显示文摘 | HE Yang YANG Shengfa ZHANG Shuaishuai | 2013 | Journal of Chongqing Jiaotong University (Natural Science)2013，32，1： | 1 |
| 11 | Deter- mining the Existence of the Fine Sediment Floccula- tion in the Three Gorges Reservoir显示文摘 | Li Weniie Wang Jie Yang Shengfa | 2015 | Journal of Hydraulic Engineering2015，14，05： | 1 |
| 12 | Modified intelligent scissors and adaptive frame skipping for video object segmentation 显示文摘 | Yang Gaobo Yu Shengfa | 2005 | Real- Time Imaging2005，11，4： | 1 |
| 13 | Finite element analysis of the electromagnetic field of untouched permanent induction magnetic coupling 显示文摘 | Yang Chaojun Wang Yuning Jiang Shengfa | 2006 | Materials Science Forum2006，，： | 1 |
| 14 | Finite ele-ment analysis of the electromagnetic field of untouchedpermanent induction magnetic coupling显示文摘 | Yang Chaojun Wang Yuning Jiang Shengfa | 2006 | MaterialsScience Forum2006，，： | 1 |
| 15 | Gravel excavation and geomorphic evolution of the mining affected river in the upstream reach of the Yangtze River,China显示文摘As economic development upstream in the Yangtze River basin has progressed in recent decades,the demand for sediment has rapidly increased and contributed to an expansion in sediment excavation that may affect the river's stability and navigation safety.In the current study,the distribution of gravel mining in the upstream reach of the Yangtze River was investigated using field measurements obtained from 2008 to 2017.An experimental investigation was then done to analyze the bed load behavior in a typical mined channel using a physical river model.Finally,a two-dimensional hydrodynamic-sediment transport numerical model was developed to predict the evolution of the mined channel.The results indicate that gravel mining was mainly distributed among the following nine river sections:Tongluoxia-Yibin,Erlong-Xianglutan,Naxi-Jinkou,Binpangqi-Hongyanqi,Chayuqi-Shenbeizui,Yangshipan-Shangbaisha,Dongxikou,Baisha-Wenzhongba,and Jiangjin-Shenzhongba.The gravel shoals near the riverbank have been destroyed,and the bed topography has been altered by up to 1.65×10^(9)m^(3)over the past 10 years.A bed load velocity formula was proposed to describe bed load transport in the mined channel based on dimensional analysis.The recovery process of the excavation pits was slow in both the experiments and simulations,with only 0.12%and 1.39%,respectively,of the mined amounts of gravel being restored.Finally,the recovery rate of the mining pits gradually slowed as the sediment supply from upstream decreased,suggesting that the destroyed gravel shoals rarely returned to their original forms due to the combined operation of hydro-projects in upstream areas and limited sediment storage in the channel. | Yi Xiao Wenjie Li Shengfa Yang | 2022 | International Journal of Sediment Research2022，37，2： | 0 |
| 16 | Self-similarity of spanwise rotational motions’population trends in decelerating open-channel flow显示文摘Decelerating open-channel flow is a type of flow that gradually moves forward with decreasing velocity and increasing water depth.Although all flow parameters change along the streamwise direction,previous studies have revealed that these parameters’vertical distributions at different sections can be universally described with a single profile when being nondimensionalised by appropriate scales.This study focuses on the population trends of spanwise rotational motions at various sections along the main flow direction by particle imaging velocimetry(PIV)measurement.The wall-normal population distributions of density,radius,swirling strength,and convection velocity of the prograde and retrograde motions show similar trends in uniform open-channel flows.The dimensionless representation is invariant along the main flow direction.This study’s results indicate the self-similar characteristic of population trends of spanwise rotational motions prevails in decelerating open-channel flow. | Peng Zhang Yanchong Duan Qiang Zhong Danxun Li Shengfa Yang Jiang Hu Wenjie Li | 2022 | Theoretical & Applied Mechanics Letters2022，12，3： | 0 |
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