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SIMULATION OF LOW-CONCENTRATION SEDIMENT-LADEN FLOW BASED ON TWO-PHASE FLOW THEORY

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Journal of Hydrodynamics 2007年第5期19卷 653-660页

作者： LIU shi-he zhao shi-lai LUO Qiu-shi School of Water Resource and Hydropower Wuhan University Wuhan 430072 China

Low concentration sediment-laden flow is usually involved in water conservancy, environmental protection, navigation and so on. In this article, a mathematical model for low-concentration sediment-laden flow was suggested based on the two-phase flow theory, and a solving scheme for the mathematical model in curvilinear grids was worked out. The observed data in the Zhang River in China was used for the ver/fication of the model, and the calculated results of the water level, velocity and river bed deformation are in agreement with the observed ones.

关键词： two-phase flow sediment-laden flow,numerical simulation

Wire-like nano-polyaniline deposited electrochemically in a reverse micelle electrolyte as a p H sensor

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International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1115-1119页

作者： Fei zhao Han-dong Jiao shi-qiang zhao State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

Wire-like polyaniline(PANI) films were successfully electrodeposited onto an indium tin oxide(ITO) substrate using a pulse galvanostatic method(PGM) in a reverse micelle electrolyte. The as-prepared PANI films were electrochemically analyzed by cyclic voltammetry and electrochemical impedance spectroscopy in 1 mol·L-1 HCl O4 solution. It is found that the as-prepared PANI films are highly porous, exhibit the diameters of approximately 100 nm and the lengths exceeding 3 μm, and have favorable electrochemical activities. Furthermore, the as-prepared wire-like PANI films show a good linear relationship of the potentiometric response curve over the p H value range of 3–10 with a slope of 74.13 m V·p H-1 in 0.5 mol·L-1 K2HPO4 basal solutions. The results demonstrate that the prepared wire-like PANI films are promising p H sensors.

关键词： electrodeposition polymers sensors thin films

On the Random Conjugate Spaces of a Random Locally Convex Module

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Acta Mathematica Sinica,English Series 2012年第4期28卷 687-696页

作者： Tie Xin GUO shi En zhao LMIB and School of Mathematics and Systems Science Beihang University

Theoretically speaking, there are four kinds of possibilities to define the random conjugate space of a random locally convex module. The purpose of this paper is to prove that among the four kinds there are only two which are universally suitable for the current development of the theory of random conjugate spaces. In this process, we also obtain a somewhat surprising and crucial result： if the base （Ω,F, P） of a random normed module is nonatomic then the random normed module is a totally disconnected topological space when it is endowed with the locally L0-convex topology.

关键词： Random locally convex module (ε λ)-topology locally L0-convex topology random con-jugate space

Wall-modeled large-eddy simulation of noise generated by turbulence around an appended axisymmetric body of revolution

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Journal of Hydrodynamics 2022年第4期34卷 533-554页

作者： Zhi-teng Zhou zhao-yue Xu shi-zhao Wang Guo-wei He LNM Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100149China

The directivity of the noise generated by turbulent flows around an underwater vehicle(the fully appended SUBOFF body)is investigated numerically,where the turbulent flows are simulated by using the large eddy simulation(LES)with a non-equilibrium wall model and the noise is calculated by using the Ffowcs Williams and Hawking *** wall-modeled LES reproduces the features of turbulent flows around SUBOFF,such as the attached boundary layers around the hull,separated vortices from appendages and the wrapped vortices in *** coefficients and power spectral density of the wall pressures obtained are in agreement with the previous numerical results and experimental *** is found that the constructive and destructive interferences of lift and side-force dipoles lead to the deviations of the directivities of instantaneous sound pressures from the lift *** is different from noise generated by flows around a circular cylinder,where lift dipoles dominate the radiated noise.

关键词： Large eddy simulation(LES) turbulence-generated noise axisymmetric body of revolution SUBOFF

Premature Tapetum Degeneration: a Major Cause of Abortive Pollen Development in Photoperiod Sensitive Genic Male Sterility in Rice

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Journal of Integrative Plant Biology 2009年第8期51卷 774-781页

作者： Yinlian shi Sha zhao Jialing Yao College of Life Science and Technology Huazhong Agricultural University Wuhan 430070 China

Photoperiod-sensitive genic male-sterile （PSGMS） rice （Oryza sativa L.）, a natural mutant found in the rice cultivar Nongken 58, is very useful for the development of hybrid rice cultivars. Despite its widespread use in breeding programs, the initial stage of the abortive development of PSGMS rice and the possible cytological mechanisms of pollen abortion have not been determined. In the present study, a systematic cytological comparison of the anther development of PSGMS rice with its normal fertile counterpart is conducted. The results show that pollen abortion in PSGMS rice first occurs before the pollen mother cell （PMC） stage, and continues during the entire process of pollen development until pollen degradation. The abortive process was closely associated with the abnormal behavior of the tapetum. Although tapetum degeneration in PSGMS rice initiates already at the PMC stage, it proceeds slowly and does not complete until the breakdown of the pollen. Such cytological observations were supported by the results of the TUNEL （TdT-mediated dUTP Nick End Labeling） assay, which detects DNA fragmentation resulting from programmed cell death （PCD）, indicating that the premature tapetum degeneration is in the process of PCD.

关键词： male-sterility Oryza sativa programmed cell death tapetum ultrastructure

A New Single-blade Based Hybrid CFD Method for Hovering and Forward-flight Rotor Computation

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Chinese Journal of Aeronautics 2011年第2期24卷 127-135页

作者： shi Yongjie zhao Qijun FAN Feng XU Guohua National Key Laboratory of Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A hybrid Euler/full potential/Lagrangian wake method,based on single-blade simulation,for predicting unsteady aerodynamic flow around helicopter rotors in hover and forward flight has been *** this method,an Euler solver is used to model the near wake evolution and transonic flow phenomena in the vicinity of the blade,and a full potential equation（FPE） is used to model the isentropic potential flow region far away from the rotor,while the wake effects of other blades and the far wake are incorporated into the flow solution as an induced inflow distribution using a Lagrangian based wake *** further reduce the execution time,the computational fluid dynamics（CFD） solution and rotor wake analysis（including induced velocity up-date） are conducted parallelly,and a load balancing strategy is employed to account for the information exchange between two *** the developed method,several hover and forward-flight cases on Caradonna-Tung and Helishape 7A rotors are *** agreements of the loadings on blade surface with available measured data demonstrate the validation of the ***,the CPU time required for different computation runs is compared in the paper,and the results show that the pre-sent hybrid method is superior to conventional CFD method in time cost,and will be more efficient with the number of blades increasing.

关键词： hybrid CFD method Euler equations full potential equations wake model rotor helicopters

INFLUENCE OF CLAY ON THE MORPHOLOGY AND PHASE SEPARATION BEHAVIOR OF POLY(METHYL METHACRYLATE)/POLY(STYRENE-co-ACRYLONITRILE) BLENDS

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Chinese Journal of Polymer Science 2013年第11期31卷 1470-1483页

作者： De-zheng Pang 左敏 Ji-shi zhao 郑强 Key Laboratory of Macromolecule Synthesis and Functionalization Ministry of EducationDepartment of Polymer Science and EngineeringZhejiang University

The effect of clay on the morphology and phase-separation behavior of poly（methyl methacrylate）/poly（styrene- co-acrylonitrile）（PMMA/SAN） blends and the variation of clay dispersion have been investigated. With the evolution of phase separation in PMMA/SAN, most of the clays are first located at the boundaries between PMMA and SAN, and then gradually move to the PMMA-rich domain, owing to the affinity of clay to PMMA. The introduction of clay causes the increase of binodal and spinodal temperatures of PMMA/SAN and enlarges their metastable region, indicating the phase stabilizing effect of clay on the matrix. But the influence of clay on the cloud points obviously depends on the composition of PMMA/SAN. The selective adsorption of PMMA on the clay results in the difference between the composition of surface layer and that of polymer matrix. Hence, the clay plays the role of an agent changing the conditions of phase structure formation.

关键词： Nanocomposites PMMA/SAN blend Clay Phase separation behavior Morphology.

The study of electroless Ni-W-P alloy plating on glass fibers

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Rare Metals 2007年第4期26卷 365-371页

作者： HUANG Ying HUANG Fei zhao Wentao shi Ke zhao Li WANG Yanli DeparUnent of Applied Chemistry School of Science Northwestern Polytechnical University Xi＇an 710072 China

Ni-W-P coatings were deposited on the surface of glass fibers by the electroless plating process. The bath was very stable through the palladium salt test. There was no phenomenon of peeling and blistering on the surface of the Ni-W-P alloy glass fibers in the thermal shock test. It showed that the deposit had high impact strength and good adhesion. The morphology of the coatings was observed by scanning electron microscope （SEM）. The elements and their contents were tested and analyzed by energy dispersion spectrometer （EDS）. The tungsten content reached up to 12.1 wt.%. The effects of the concentrations of NiSO4, Na2WO4, and NaH2PO2.H20 on the conductivity of the coatings were studied. The resistivity of the Ni-W-P alloy glass fibers reached 7.39 × 10^-3 Ωcm. The alloy coatings on glass fibers were analyzed by XRD. The results indicated that the deposit had an amorphous structure and good heat stability. The suitable work temperature range was lower than 190℃. Finally, the electromagnetic parameters of the Ni-W-P alloy glass fibers were tested and analyzed primarily. The magnetic loss reached 0.04023 and the dielectric loss reached -5.80239. The plated alloy is a kind of soft magnetic material.

关键词： Ni-W-P alloy electroless plating resistivity electromagnetic parameters glass fiber

Activity of comet 103P/Hartley 2 from September 30 to November 04, 2010

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Science China(Physics,Mechanics & Astronomy) 2012年第8期55卷 1515-1518页

作者： shi JlanChun zhao HaiBin MA YueHua Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

The CCD photometric observation of comet 103P/Hartley 2 with broadband optical filters was carried out at Xuyi Station of Purple Mountain Observatory, Chinese Academy of Sciences by use of Near Earth Object Telescope （NEOT）. We monitored the comet from September 30 to November 4, 2010 and investigated the variation of activities. The Afp parameter derived from our r broadband data varies from 46.0 to 126.0 cm and increases with time. The dust production rate in terms of Afp was measured and a tentative calculation of the dust （or gas） loss-rate of nucleus was executed under the assumption that the nucleus of comet 103P/l-lartley 2 is spherical. The r-band image and the surface brightness profile taken on September 30, 2010 was measured and the gradient of surface brightness profile of 103P/Hartley 2 showed m 〈 -1.5,

关键词： comets 103P/Hartley 2 activity