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Nutrient exchange and release experiment and its simulation study in lake water-sediment interface

Journal of Environmental Sciences 2006年第3期18卷 591-595页

作者： xue lian-qing HAO Zhen-chun State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering College of Water Resources and Environment Hohai UniversityNanjing 210098 China

The sediment distributed and insolated under lake was collected for experiments. The nutrient layer distribution conditions of sampled sediment and its physical and chemical characteristics were analyzed to simulate and assess the influence degree to lake water quality. Based on the dynamic water exchanging experiments the nutrient release process in sediment and influence mechanism to substance exchanging on water-sediment interface was studied, and the correlation between the changing content of total phosphors and total nitrogen in sediment and covered water were analyzed for setting up a simulation model. At the same time the influence degree is explained in detail. The experimental results indicated that even if clean water without nutrient contents was used for water exchangement so as to decrease pollution or prevent eutrophication, however owing to the vertical nutrient distribution in lake sediment, it will lead to the increasing release amount greatly especially when the organic nutrient contained in sediment turns into inorganic status because of isolation. Besides the release process of total phosphate （TP） and total nitrogen （TN） were modeled and each nutrient＇s exchanging equation at interface caused by covered water nutrient concentration changing was set up. According to the simulating prediction, TP and TN content of cover water will also sustain a steady higher level in a long period. The nutrient release amount of sediment is not only affected by the covered water concentration but also connects with accumulative time. The experiments provide the fundamental theoretical and practical basis for taking ecological restoration project. And research is helpful to prevent or restore lake eutrophication.

关键词： phosphate and nitrogen release water-sediment interface experiments simulation model

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Co-design for an SoC embedded network controller

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第4期7卷 591-596页

作者： ZOU lian-ying ZOU xue-cheng Department of Electronic Science ＆ Technology Huazhong University of Science ＆ Technology Wuhan 430074 China

With the development of Ethernet systems and the growing capacity of modem silicon technology, embedded communication networks are playing an increasingly important role in embedded and safety critical systems. Hardware/software co-design is a methodology for solving design problems in processor based embedded systems. In this work, we implemented a new 1-cycle pipeline microprocessor and a fast Ethemet transceiver and established a low cost, high performance embedded network controller, and designed a TCP/IP stack to access the Intemet. We discussed the hardware/software architecture in the forepart, and then the whole system-on-a-chip on Altera Stratix EP1S25F780C6 device. Using the FPGA environment and SmartBit tester, we tested the system＇s throughput. Our simulation results showed that the maximum throughput of Ethemet packets is up to 7 Mbps, that of UDP packets is up to 5.8 Mbps, and that of TCP packets is up to 3.4 Mbps, which showed that this embedded system can easily transmit basic voice and video signals through Ethemet, and that using only one chip can realize that many electronic devices access to the Intemet directly and get high performance.

关键词： System-on-Chip (SoC) Embedded Microprocessor Network controller TCP/IP Co-design

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Peak Dynamic Pressure on Semi-and Quarter-Circular Breakwaters Under Wave Troughs

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China Ocean Engineering 2017年第2期31卷 151-159页

作者： JIANG xue-lian ZOU Qing-ping SONG Ji-ning State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin Key Laboratory of Soft Soil Characteristics & Engineering Environment School of Civil EngineeringTianjin Chengjian University Department of Civil and Environmental Engineering The University of Maine State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

A series of physical tests are conducted to examine the characteristics of the wave loading exerted on circular-front breakwaters by regular waves. It is found that the wave trough instead of wave crest plays a major role in the failure of submerged circular caissons due to seaward sliding. The difference in the behavior of seaward and shoreward horizontal wave forces is explained based on the variations of dynamic pressure with wave parameters. A wave load model is proposed based on a modified first-order solution for the dynamic pressure on submerged circular-front caissons under a wave trough. This wave loading model is very useful for engineering design. Further studies are needed to include model uncertainties in the reliability assessment of the breakwater.

关键词： semicircular breakwater quarter-circular breakwater wave trough load seaward wave force shoreward wave force

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Local and regional flood frequency analysis based on hierarchical Bayesian model in Dongting Lake Basin,China

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Water Science and Engineering 2019年第4期12卷 253-262页

作者： Yun-biao Wu lian-qing xue Yuan-hong Liu College of Hydrology and Water Resources Hohai UniversityNanjing 210098China Department of Fundamental Education Wanjiang University of TechnologyMaanshan 243031China College of Water and Architectural Engineering Shihezi UniversityShihezi 832003China

This study developed a hierarchical Bayesian(HB)model for local and regional flood frequency analysis in the Dongting Lake Basin,in *** annual maximum daily flows from 15 streamflow-gauged sites in the study area were analyzed with the HB *** generalized extreme value(GEV)distribution was selected as the extreme flood distribution,and the GEV distribution location and scale parameters were spatially modeled through a regression approach with the drainage area as a *** Markov chain Monte Carlo(MCMC)method with Gibbs sampling was employed to calculate the posterior distribution in the HB *** results showed that the proposed HB model provided satisfactory Bayesian credible intervals for flood quantiles,while the traditional delta method could not provide reliable uncertainty estimations for large flood quantiles,due to the fact that the lower confidence bounds tended to decrease as the return periods ***,the HB model for regional analysis allowed for a reduction in the value of some restrictive assumptions in the traditional index flood method,such as the homogeneity region assumption and the scale invariance *** HB model can also provide an uncertainty band of flood quantile prediction at a poorly gauged or ungauged site,but the index flood method with L-moments does not demonstrate this uncertainty ***,the HB model is an effective method of implementing the flexible local and regional frequency analysis scheme,and of quantifying the associated predictive uncertainty.

关键词： Flood frequency analysis Hierarchical Bayesian model Index flood method Generalized extreme value distribution Dongting Lake Basin

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Flow Separation and Vortex Dynamics in Waves Propagating over A Submerged Quartercircular Breakwater

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China Ocean Engineering 2018年第5期32卷 514-523页

作者： JIANG xue-lian YANG Tian ZOU Qing-ping GU Han-bin Tianjin Key Laboratory of Soft Soil Characteristics & Engineering Environment Tianjin Chengjian University State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University The Lyell Centre for Earth and Marine Science and Technology Institute for Infrastructure and EnvironmentHeriot-Watt University School of Naval Architecture &Mechanical-Electrical Engineering Zhejiang Ocean University

The interactions of cnoidal waves with a submerged quartercircular breakwater are investigated by a ReynoldsAveraged Navier–Stokes(RANS) flow solver with a Volume of Fluid(VOF) surface capturing scheme(RANSVOF) model. The vertical variation of the instantaneous velocity indicates that flow separation occurs at the boundary layer near the breakwater. The temporal evolution of the velocity and vorticity fields demonstrates vortex generation and shedding around the submerged quartercircular breakwater due to the flow separation. An empirical relationship between the vortex intensity and a few hydrodynamic parameters is proposed based on parametric analysis. In addition, the instantaneous and time-averaged vorticity fields reveal a pair of vortices of opposite signs at the breakwater which are expected to have significant effect on sediment entrainment, suspension, and transportation,therefore, scour on the leeside of the breakwater.

关键词： submerged quartercircular breakwater cnoidal wave flow separation vortex dynamics scour

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Novel chiral thioureas for highly enantioselective Michael reactions of malonates to nitroalkenes

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Chinese Chemical Letters 2009年第3期20卷 310-313页

作者： Li Jun Yan Quan Zhong Liu xue lian Wang Laboratory of Applied Chemistry and Pollution Control Technology College of Chemistry and Chemical Engineering China West Normal University Nanchong 637002 China

Highly efficient Michael addition reactions of malonates to nitroalkenes catalyzed by novel chiral thioureas derived from optically pure BINOL and amino acids are reported. Various trans-nitroalkenes reacted with malo... 详细信息

关键词： Michael addition Thiourea Enantioselectivities Nitroalkene and malonate

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Autocorrelation of two Legendre-Sidelnikov sequences

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The Journal of China Universities of Posts and Telecommunications 2014年第5期21卷 83-88,93页

作者： XIE Jia GAO Jun-tao YUE Zhao LI xue-lian The State Key Laboratory of Integrated Services Network Xidian University Department of Mathematics Xidian University State Key Laboratory of Information Security Chinese Academy of Sciences

Sequences with nice pseudo-randomness play an important role in not only communication system but also cryptography system. Based on the Legendre-Sidelnikov sequence, a modified Legendre-Sidelnikov sequence was introduced. The exact value of the autocorrelation function was derived by strict computation. According to the values of the autocorrelation functions of the two Legendre-Sidelnikov sequences, it is proven that both of them have perfect pseudo-randomness. Furthermore, a detailed comparison between autocorrelation functions of the two Legendre-Sidelnikov sequences was deduced. It indicates that no matter which parameters are chosen, the modified sequence has pseudo-randomness as good as the primitive sequence, which is of great significance for applications.

关键词： autocorrelation pseudo-randomness binary sequence quadratic character Legendre-Sidelnikov sequence two-prime generator

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Fiber-shaped Supercapacitors:Advanced Strategies toward High-performances and Multi-functions

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Chinese Journal of Polymer Science 2020年第5期38卷 403-422,I0004页

作者： Jie Yang xue-lian Lia Jing-Wen Zhou Bin Wang Jian-Li Cheng Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China Sichuan Research Center of New Materials Chengdu 610200China

Fiber-shaped supercapacitors(FSSCs)show great potential in portable and wearable electronics due to their unique advantages of high safety,environmental friendliness,high performances,outstanding flexibility and *** can directly act as the power sources or be easily integrated with other flexible devices to constitute self-powered and sustainable energy suppliers,providing excellent adaptability to irregular *** review mainly summarizes the recently reported works of FSSCs including preparation methods of various fiber electrodes,construction strategies of FSSCs and multi-functional device integrations,exploration of reaction mechanisms and strategies to improve the electrochemical performance and provision of suggestions on further designing and optimization of ***,it shares our perspectives on challenges and opportunities in this field,shedding light on the development of high-performance fiber-shaped supercapacitors with multifunctions.

关键词： Fiber-shaped supercapacitor Performance improvement Multi-function device Integrated electronics

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Synthesis and Primary Research on Antitumor Activity of Three New Panaxadiol Fatty Acid Esters

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Chemical Research in Chinese Universities 2007年第2期23卷 176-182页

作者： ZHANG Chun-hong LI Xiang-gao GAO Yu-gang ZHANG lian-xue FU xue-qi Academy of Chinese Traditiorial Medicine Jilin Agricultural University Changchun 130118 P. R. China Edmond H. Fischer Signal Transduction Laboratory College of Life Sciences Jilin University Changchun 130021 P. R. China

For making use of Ginseng resources that exhibit an antitumor activity and for finding new anticancer drugs, three new fatty acid ester compounds： 3/β-acetoxy panaxadiol （ Ⅰ ）, 3β-palmitic acid aceloxy panaxadiol （ Ⅱ ） , and 3β-octadecanoic acid aceloxy panaxadiol（ Ⅰ , Ⅱ, and m） were synthesized with panaxadiol, diacetyl oxide, palmityl chloride and stearyl chloride, and their structures were determined via MS, ^13C NMR, IR, TLC, and so on. The molar yields of the three compounds are 75.14%, 79. 08%, and 72. 57%, respectively. Meanwhile, the antitumor activity of the three new panaxadiol fatty acid ester derivatives and panaxadiol was compared by using the method of MTT. Tumor cell used was Vero cell line. Positive control was 5-FU, blank was an RPMI1640 culture medium, negative control was an RPMI1640 culture medium and the solvent for drugs to be tested. Compound Ⅰ has the strongest antitumor activity followed by panaxadiol; compounds Ⅱ and Ⅲ have similar and weakest antitumor activities. Furthermore, the antitumor activities of the panaxadiol fatty acid ester derivatives show positive correlation with the concentration of the test group, but show no relationship with the molecular weight of fatty acid. The methods that are used to synthesize the three compounds with high yields and strong antitumor activities are simple and show a great potential for meeting the needs of industrial manufacture of these drugs.

关键词： Synthesis Panaxadiol fatty acid esters Anti-tumor activity

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Quasi-static motion of microparticles at the depinning contact line of an evaporating droplet on PDMS surface

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Science China(Physics,Mechanics & Astronomy) 2017年第9期60卷 63-69页

作者： Ying-Song Yu xue-lian Xia Xu Zheng Xianfu Huang Jin-Zhi Zhou Department of Mechanics School of Civil Architecture and Environment Hubei University of Technology State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

In this paper, evaporation of sessile water droplets containing fluorescent polystyrene （PS） microparticles on polydimethylsiloxane （PDMS） surfaces with different curing ratios was studied experimentally using laser confocal microscopy. At the beginning, there were some microparticles located at the contact line and some microparticles moved towards the line. Due to contact angle hysteresis, at first both the contact line and the microparticles were pinned. With the depinning contact line, the microparticles moved together spontaneously. Using the software Image J, the location of contact lines at different time were acquired and the circle centers and radii of the contact lines were obtained via the least square method. Then the average distance of two neighbor contact lines at a certain time interval was obtained to characterize the motion of the contact line. Fitting the distance-time curve at the depinning contact line stage with polynomials and differentiating the polynomials with time, we obtained the velocity and acceleration of both the contact line and the microparticles located at the line. The velocity and the maximum acceleration were, respectively, of the orders of 1 p.m/s and 20-200 nm/s2, indicating that the motion of the microparticles located at the depinning contact line was quasi-static. Finally, we presented a theoretical model to describe the quasi-static process, which may help in understanding both self-pinning and depinning of microparticles.

关键词： droplet evaporation PDMS contact line van der Waals force electrostatic force drag force capillary force

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