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On the siltation of the middle Yangtze River

Science china Earth Sciences 2004年第5期47卷 463-480页

作者： YIN Hongfu1, CHEN Guojin2. LI Chang抋n1 & WEI Yuan3 1. school of Earth Sciences, china {2. of Geosciences, Wuhan 430074, china 2. Hydrogeological Team, Hubei Bureau of Geology and Mineral Resources, Jingzhou 434100, china 3. Geological Survey of jiangxi Province, nanchang 3302.1, china china Univ Geosci Sch Earth Sci Wuhan 430074 Peoples R China Hubei Bur Geol & Mineral Resources Hydrogeol Team Jinzhou 434100 Peoples R China Geol Survey jiangxi Province Nanchang 3300201 Peoples R China

About 5.2.108 t/a of silts from the upper reach of the Yangtze River are transported through Yichang into the middle Yangtze River. The middle Yangtze itself and its tributaries yield ca. 0.8×108 t silts annually. Of this total 6×108 t/a input of silts, ca. 1.2.108 t/a are deposited within the river artery and lakes, while ca 4.83×108 t/a are at first transported into the lower reach through Datong, and then either deposited along the river and the Yangtze Delta, or output into the sea. Along the middle Yangtze River silting generally exceeds scouring, but the spatial and temporal distributions of scour-and-fill, as well as its distribution in the river valley transections, are uneven. Along the Yichang-Chenglingji and Jiujiang-Datong Segments of the middle Yangtze, scouring exceeds or equals silting. Silting mainly occurs along the Luoshan-Wuhan-Huangshi Segments with Wuhan as the pivotal point, as well as in the Dongting and Poyang Lakes. Even in these silting-dominated areas, there are times and parts of segments that scouring prevails. As to the transections, generally the river channel of main stream is scouring-dominated, forming V-shaped sections to a depth of 2.30 m or more, whereas the floodplains and bar islands are silting-dominated, forming wide and relatively high flats, which are often artificially transformed into protected embankments. Because the Jingjiang Levee separates the Jianghan Plain from Yangtze to the south, little has been deposited in that plain except a few sediments from the Han River—a tributary of the middle Yangtze. This factor plus the tectonic sag of that plain has made the altitude of plain surface several meters lower than that of the levee in most of the areas. Sil-tation along the Luoshan-Wuhan-Huangshi Segments has resulted in the elevation of flood level in this and upstream segments. River channel scouring plus floodplain silting have caused the transections of the middle Yangtze valley typically with deep channel and height

关键词： the middle Yangtze, scour-and-fill, siltation, silt utilization.

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Feature combination for classifying single-trial ECoG during motor imagery of different sessions

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Progress in Natural Science:Materials International 2007年第7期17卷 851-858页

作者： Wei Qingguo~(1,2. Meng Fei~1 Wang Yijun~1 Gao Xiaorong~1 Gao Shangkai~(1**) (1.Department of Biomedical engineering,school of Medicine,Tsinghua {2.,Beijing 100084,china 2.Department of Electronic engineering,school of Information,nanchang {2.,nanchang 33002.,china) [a]Department of Biomedical engineering School of Medicine TsinghuaUniversity Beijing China [b]Department of Electronic engineering School of Information Nanchang University Nanchang China

The input signals of brain-computer interfaces(BCIs)may be either scalp electroencephalogram(EEG)or electrocor- ticogram(ECoG)recorded from subdural *** make BCIs practical,the classifiers for discriminating different brain states must have the ability of session-to-session *** paper proposes an algorithm for classifying single-trial ECoG during motor imagery of different *** features,derived from two physiological phenomena,movement-related potentials(MRP)and event-related desynchronization(ERD),and extracted by common spatial subspace decomposition(CSSD)and waveform mean,are combined to per- form classification *** specific signal processing methods utilized are described in *** algorithm was successfully applied to Data SetⅠof BCI CompetitionⅢ,and achieved a classification accuracy of 91% on test set.

关键词： brain-computer interface(BCI) electrocorticogram(ECoG) session-to-session transfer feature combination movement-related potentials(MRP) event-related desynchronization(ERD)

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Hydrothermal Treatment of Sol-Gel TiO2.Film

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稀有金属材料与工程 2006年第S3期 570-571页

作者： Shaohua Zhang~1 Bing Xie~2.Fengyi Li~3 Tude Zou~2.(1.school of Materials,nanchang {2.,jiangxi 330047,china) (2.Center of Analysis and Test,nanchang {2.,jiangxi 330047,china) (3.school of Science,nanchang {2.,jiangxi 330047,china)

The preparation of TiO2.ilm has been an important research *** our work,we obtained the TiO2.ilm by hydrothermal treating the amorphous film prepared by sol-gel method or the hydrolysis of titanium *** influence of temperature and duration time on the film properties was *** photo degradation of methyl orange in aqueous solution of the film was *** films were characterized by XRD and Uv-Vis spectroscope.

关键词： titania film hydrothermal sol-gel

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Synthesis of vertically aligned carbon nanotube arrays on silicon substrates

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Science china(Technological Sciences) 2004年第5期47卷 616-624页

作者： ZHENG Ruiting1, CHENG Guoan1, PENG Yibin1, 2. ZHAO Yong1, 3, LIU Huaping1 & LIANG Changlin1 1. Key Laboratory of Radiation Beam Technology and Materials Modification of Ministry of Education, Department of Materials Science and engineering, Beijing Normal university, Beijing 100875,{2. 2. school of Science, Civil Aviation university of{2., Tianjin 300300,{2. 3. Department of Physics, nanchang university, nanchang 330047,{2. Correspondence should be addressed to Zheng Ruiting 1. Key Laboratory of Radiation Beam Technology and Materials Modification of Ministry of Education Department of Materials Science and Engineering Beijing Normal University 100875 Beijing China 2. school of Science Civil Aviation University of China 300300 Tianjin China 3. Department of Physics Nanchang University 330047 Nanchang China

The growth of well-aligned carbon nanotube (CNT) arrays using a heat chemical vapor deposition system on silicon substrates is reported. The growth properties of CNT arrays are studied as a function of synthesis conditions. It is found that 750°C and 10 nm Fe film are suitable conditions for the growth of well-aligned CNT arrays. CNT arrays with a uniform diameter, thick tube wall and firm cohesion to the Si substrate can be grown for C2.2.concentration of 2.%. Based on the experiment, the processes of improving the alignment of CNT arrays and cohesion between CNT arrays and Si substrates are discussed.

关键词： carbon nanotubes, vertically aligned, silicon substrate, chemical vapor deposition.

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THE INVESTIGATION ON THE RHEOLOGICAL BEHAVIOR OF SEMI-SOLID ALUMINUM ALLOY DURING DIE CASTING

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Acta Metallurgica Sinica(English Letters) 2002年第6期15卷 511-516页

作者： X.J. Yang and J.Liu school of Mechanic & Electronic engineering,{2., jiangxi 33002., china school of Mechanic & Electronic engineering, Shanghai university, Shanghai 2.0072. china school of Mechanic & Electronic engineering Nanchang University Shanghai university

Under the condition of die casting and reheating temperature of 570-580 degC, the rheological behavior of semi-solid aluminum alloy (A356) is pseudoplasticity at the shearrate of 2.10^-1X10^4s^(-1), and also shows dil... 详细信息

关键词： shear rate apparent viscosity viscosity model thixocasting

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Preparation of Nano-Sized TiO2.Particles by Microemulsion Method

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稀有金属材料与工程 2006年第S3期 575-577页

作者： Shaohua Zhang~1 Bing Xie~2.Fengyi Li~3 Peng Xu~2.(1.school of Material Science and engineering,{2. Univeristy,{2. 330047,china) (2.Analysis and Test Center,{2. university,{2. 330047,china) (3.school of Science,{2. university,{2. 330047,china)

Nano-sized titania powders have been prepared by hydrolysis of tetrabutyl titanate in the droplet of water/OP-7/pentanol/cyclohexane microemulsion *** effects of ingredient change on the water drop size and particle size were *** prepared TiO2.as in the form of anatase after ***2.as characterized by TG-TGA, FTIR,XRD to measure the transformation temperature,surface adsorption and average size.

关键词： TiO2 microemulsion nano

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Atmospheric correction of HJ-1A/B CCD images over Chinese coastal waters using MODIS-Terra aerosol data

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Science china(Technological Sciences) 2010年第S1期53卷 191-195页

作者： TIAN LiQiao 1,LU JianZhong 1,CHEN XiaoLing 1,2.3,YU ZhiFeng 1,XIAO JingJing 1,QIU Feng 1 & ZHAO Xi 1 1 State Key Laboratory of Information engineering in Surveying,Mapping and Remote Sensing,Wuhan university,Wuhan 430079,{2. 2.ey Laboratory of Poyang Lake Wetland and Watershed Research,Ministry of Education,jiangxi Normal university,nanchang 33002.,{2. 3 The Key Laboratory of Poyang Lake Environment and Resource Utilization,Ministry of Education,nanchang university,nanchang 330031,{2. 1. State Key Laboratory of Information engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China 2. Key Laboratory of Poyang Lake Wetland and Watershed Research Ministry of Education Jiangxi Normal University Nanchang 330022 China 3. The Key Laboratory of Poyang Lake Environment and Resource Utilization Ministry of Education Nanchang University Nanchang 330031 China

This paper demonstrates an atmospheric correction method to process HJ-1A/B CCD images over Chinese coastal waters with the aid of MODIS-Terra aerosol *** on the assumption of zero water-leaving radiance at the two near-infrared (NIR)bands or the shortwave infrared(SWIR)bands,the atmospheric aerosol optical depth(AOD)is firstly retrieved from MODIS-Terra with a simple extension of the NIR-SWIR combined atmospheric correction approach embedded in SeaDAS (SeaWiFS data analysis system).Then the"turbid"and"non-turbid"waters are separated by the turbid water *** probability of AOD at 551 nm band is derived based on the NIR information over"non-turbid"waters and FLAASH model is selected to do the atmospheric correction of the HJ-1A/B CCD imagery using the AOD values of highest probabilities as ***,according to the histogram of the AOD distribution at 551 nm band,the studied turbid water area is divided into several blocks and HJ-1A/B CCD imagery is corrected with the corresponding AOD values displayed with the highest frequency in each *** method has been applied to several HJ-1A/B images over Chinese coastal waters and validated by synchronous in-situ *** results have shown that this method is effective in the atmospheric correction process of HJ-1A/B CCD images for ocean color remote sensing study and application in the coastal waters.

关键词： ocean color remote sensing atmospheric correction turbid coastal waters HJ-1A/B MODIS

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Research on nonlinear constitutive relationship of permanent deformation in asphalt pavements

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 671-682页

作者： PENG Miaojuan1 & XU Zhihong2.1. Department of Civil engineering,Shanghai university,Shanghai 2.0072.{2. 2. school of Transportation engineering,Tongji university,Shanghai 2.0092.{2. 1. Department of Civil engineering Shanghai University Shanghai 200072 China 2. school of Transportation engineering Tongji University Shanghai 200092 China

To predict correctly the rut depths in asphalt pavements,a new nonlinear viscoelastic-elastoplastic constitutive model of permanent deformation in asphalt pave-ments is presented. The model combines a generalized Maxwell model with an elasto-plastic one. Then from the creep theory,the linear and nonlinear constitutive equations of the generalized Maxwell model are obtained. From the nonlinear finite element method for the rutting of the asphalt pavement,the rut depths of 4 asphalt-aggregate mixtures are obtained. And the results are compared with the ones from the finite element method by SHRP and the experiments by SWK/UN. The results in this paper are better than the ones by SHRP,and agree with the ones of the experiment by SWK/UN. This shows that the nonlinear viscoelastic-elastoplastic constitutive model,which is presented in this paper for the rutting of the asphalt pavement,is effective. The properties,such as nonlinear elastic-ity,plasticity,viscoelasticity and nonlinear viscoelasticity,which affect the rutting of an asphalt pavement,can be shown in the model. And the characteristics of the permanent deformation of the asphalt pavement can be presented entirely in the model.

关键词： asphalt pavement,permanent deformation,nonlinear viscoelastic-elastoplastic constitutive relationship,generalized Maxwell model,creep compliance.

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Non-isothermal Melt Crystallization Kinetics of Anhydrite-Filled Polypropylene Composites

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Journal of Wuhan university of Technology(Materials Science) 2010年第1期25卷 12-19页

作者：王少会 Department of Chemistry and Chemical engineering East China JiaoTong University

The non-isothermal crystallization kinetics of polypropylene （PP）, PP/anhydrite composites were investigated by differential scanning calorimetry （DSC） with various cooling rates. The Avrami analysis modified by Jeziorny and a method developed by Mo were employed to describe the non-isothermal crystallization process of these samples. The difference in the exponent n between PP and PP/anhydrite composites indicated that non-isothermal kinetic crystallization corresponded to tri-dimensional growth with heterogeneous nucleation. The values of half-time, Zc and F（T） showed that the crystallization rate increased with the increasing of cooling rates for PP and PP/anhydrite composites, but the crystallization rate of PP/anhydrite composites was faster than that of PP at a given cooling rate. The method developed by Ozawa did not describe the non-isothermal crystallization process of PP very well. Moreover, the method proposed by Kissinger was used to evaluate the activation energy of the mentioned samples. The result showed that the activation energy of PP/anhydrite was greatly larger than that of PP.

关键词： polypropylene anhydrite composites non-isothermal crystallization kinetics

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Effects of Ultrasonic Field on Microstructures and Properties of Semi-solid AZ91D Magnesium Alloy

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Journal of Wuhan university of Technology(Materials Science) 2010年第4期25卷 555-560页

作者：陈国平 Mechanical engineering Institute Hunan Industry University(Zhuzhou) Mechanical and Electrical engineering Institute Nanchang University

The microstructure distribution rule of semi-solid AZ91D alloy treated by ultrasonic was researched, and mechanical properies of specimens before and after ultrasonic treatment were investigated ***-solid AZ91D melt specimens were processed by ultrasonic under different powers, and its microstructures and mechanical properties at different sampling points in specimens were obtained. The experimental results show that the microstructure of AZ91D alloy at different sampling points under the same ultrasonic power is different in grain size and shape, and there is also great difference among their microstructures at the same sampling point under different ultrasonic powers. AZ91D alloy treated by ultrasonic can obtain increment in both tensile strength and plasticity. Under same ultrasonic power, mechanical properties of specimen at different sampling points have obvious difference, and regularity for change of mechanical properties everywhere is similar to regularity for change of grain size and shape everywhere.

关键词： magnesium alloy AZ91D ultrasonic treatment semi-solid structure distribution rule

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