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Journal of Environmental Sciences 1997年第2期9卷 101-106页

作者： Ye Changming, Wang Hong, Lei Zhifang Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China

The occurrence of suspended particles and the organic chemicals biodegradation are the universal phenomenan in aquatic environment, therefore research of interfacial effects of suspended particles on biodegradation of organic compounds has became very important aspect of organic pollutants fate studies in multimedia environment. The biodegradation of N (2,4 dimethyl phenyl) N' methylformamidine hydrochloride and dibutyl phthalate, and the interfacial effects of suspended particles on biodegradation rate were studied. The interfacial effect factor was introduced to express the effect of suspended solids on biodegradation rate. The results of simulation experiment of two compounds and theoretical analysis of process show that biodegradation rate of pollutants increases linearly with interfacial effect factor.

关键词： interfacial effect suspended particles organic chemicals waters.

The curve of ion exchange ratio(%)-pH of the interaction between suspended particles with Cd(Ⅱ) in the Yellow River

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Journal of Environmental Sciences 1998年第2期10卷 125-129页

作者： Yang Hong wei, Jiao Xiao bao, Guo Bo shu Institute of Environmental Chemistry, Inner Mongolia Normal University, Huhhot 010022,China Yang Yu ying Department of Chemistry, Inner Mongolia Teachers College for Nationalities, China Song Zhi xi

The curve of ion exchange ratio(%) pH of the interaction between suspended particles with Cd(II) in the Yellow River was studied. The effects of lysine on this curve have been also investigated. The results showed that (1) Cadmium in Cd(OH) + form in the suspended particles exchanges with the cations. The exchange ratio of Cd 2+ is nearly at its greatest value in the range of pH (8.0—8.5) in natural aquatic system; (2) Ion exchange ratio decreases as the concentration of Cd 2+ raises from 8.9×10 -6 mol/L to 2×8.9×10 -6 mol/L; (3) At the lysine concentration of 6 8×10 -6 mol/L, it can promote the ion exchange ratio; (4) Adsorption of the suspended particles to cadmium is weaker in seawater and Jin Sha River than in the Yellow River.

关键词： liquid solid interaction cadmium ion exchange technique suspended particles Yellow River. 

When river meets ocean: distribution and conversion of suspended organic particles in a Sundarbans mangrove river-estuary system, Bangladesh

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Acta Oceanologica Sinica 2024年第10期43卷 63-73页

作者： Xiaochun Zou Yunhai Li Liang Wang Mohammad Kawser Ahmed Keliang Chen Jianwei Wu Yonghang Xu Yunpeng Lin Baohong Chen Kankan Wu Jinwen Liu Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China Laboratory for Marine Geology Qingdao Marine Science and Technology CenterQingdao 266237China Department of Oceanography University of DhakaDhaka 1000Bangladesh Xiamen Ocean Vocational College Xiamen 361100China Key Laboratory of Marine Ecological Conservation and Restoration Ministry of Natural ResourcesXiamen 361005China Department of Ocean Science&Engineering Southern University of Science and TechnologyShenzhen 518055China

Global carbon cycle has received extensive attention,among which the river-estuary system is one of the important links connecting the carbon cycle between land and *** this paper,the distribution and control factors of particulate organic carbon(POC)were studied by using the data of organic carbon contents and its carbon isotopic composition(δ13C)in the mainstream and estuary of Passur River in the Sundarbans area,combined with the hydrological and biological data measured by *** results show that POC content ranged from 0.263 mg/L to 9.292 mg/L,and the POC content in the river section(averaged 4.129 mg/L)was significantly higher than that in the estuary area(averaged 0.858 mg/L).Two distinct stages of POC transport from land to sea in the Sundarbans area were *** first stage occurred in the river section,where POC distribution was mainly controlled by the dynamic process of runoff and the organic carbon was mainly terrestrial *** second stage occurred during estuarine mixing,where the POC distribution was mainly controlled by the mixing process of seawater and *** source of POC was predominantly marine and exhibiting vertical *** surface and middle layers were primarily influenced by marine sources,while the bottom layer was jointly controlled by terrestrial and marine sources of organic *** findings are of great significance for understanding the carbon cycle in such a large mangrove ecosystem like the Sundarbans mangrove.

关键词： suspended particles particle organic carbon Sundarbans mangrove river-estuary system

THE DISTRIBUTION OF SOLID particles suspended IN A TURBULENT FLOW:A STOCHASTIC APPROACH

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Acta Mechanica Sinica 1991年第2期7卷 123-130页

作者： Shao Xuejun Xia Zhenhuan (Department of Hydraulic Engineering,Tsinghua University) Department of Hydraulic Engineering Tsinghua University Beijing China

Basic fluid mechanics and stochastic theories are applied to show that the concentration distribution of suspended solid particles in a direction normal to the mean streamlines of a two-dimensional turbulent flow is greatly influenced by the lift force exerted on them in the vicinity of the *** solution shows that,when the direction of the mean flow is horizontal,the probability density function p(y,t)for random displacements of the particles will have a maximum value at a point from the wall where the perpendicular component of the lift force precisely balances particle *** of experimental observations is presented using this theory.

关键词： suspended particles turbulent diffusion random motion probability density distribution

STOCHASTIC THEORY OF THE DISTRIBUTION OF SEDIMENT particles suspended IN A TURBULENT FLOW

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International Journal of Sediment Research 1991年第2期 41-59页

作者： SHAO Xuejun and XIA Zhenhuan ①Lecturer, Deportment of Hydraulic Engineering, Tsinghua University, Beijing China ②Professor, Department of Hydraulic Engineering Tsinghua University, Beijing, China

The random motion of sediment particles suspended in a turbulent flow is studied by means of stochastic process. Results of analysis of particle’s frequency response to the random force exerted on the particle due to fluid turbulence suggest that only the lower part of the whole frequency range of the eddy motion will govern the motion of the particle. The mean values of particle velocity and displacement in the vertical direc- tion are calculated and it is found that particle velocity vp- can be decomposed into a mean motion and a velocity fluctuation vp- , where is equal to the fall velocity in tranquil fluid. An Ito^ random differential equation for particle dis- placement Yp is developed, from which a Fokker-Planck equation for the probability density function p(y,t) is derived on the basis of the theory of Markov process, where y denotes the vertical coordinate. The vertical distribution of the particle is thus interrelated to the random motion of the particle. The an effect that a particle will be subject to in the neighborhood or the bottom boundary is taken into consideration and a corresponding Fokker-Planck equation is developed. Analytical solution of the Fok- ker-Planck equation including the lift force effect shows that probability density p(y,t) for the particle displacement has a maximum value at y = H where the perpen- dicular component of the lift force balances the particle gravity. This theoretical result agrees with experimental observations as reported in literature.

关键词： suspended particles Stochastic theory Turbulence diffusion Fre- quency response Probability density function.

Quantitative relationship between flagellate abundance and suspended particle density in Huanghai Sea and East China Sea in summer

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Acta Oceanologica Sinica 2006年第2期25卷 109-118页

作者： HUANG Lingfeng PAN Ke GUO Feng Department of Oceanography ＆ Institute of Subtropical Oceanography Xiamen University Xiamen 361005 China State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China

An investigation was carried out in the Huanghai Sea and the East China Sea to study the quantitative relationship between the abundance of flagellates and the density of suspended particles in the summer of 2001. The results show that the abundance of flagellates varies from 44-12 600 cell/cm^3, and flagellates sometimes constitutes a significant part of suspended particles. The size-spectra of suspended particles can be divided into four categories： flat spectrum, humped spectrum, plankton spectrum and mixed spectrum. In general, the abundance of flagellates varies in proportion to the density of suspended particles. However, their quantitative relations reveal different characteristics in the seawater samples of different types of particle-size spectrum. This is only a preliminary study of the quantitative relationship between flagellates and suspended particles, which might lead to a potential convenient approach to the estimation of flagellate abundance in the sea.

关键词： marine flagellates suspended particles particle-size spectra quantitative relationship

Characteristics of metal enrichment in Deep Bay,Hong Kong

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Journal of Environmental Sciences 2004年第1期16卷 9-12页

作者： LIUWen-xin LIXiang-dong LIYok-sheung WAIWing-hongOnyx O.W.H.Wai DepartmentofCivil＆StructuralEngineering TheHongKongPolytechnicUniversityHungHomKowloonHongKong SKLEAC ResearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085China

Sediment cores, suspended particles and overlying water were collected in Deep Bay, Hong Kong. Enrichment of Zn in surface sediments in the landward direction and the decreasing of exchangeable Cd, Ni and Zn in sediment from the inner bay to the outer bay indicated the influence of anthropogenic pollutants discharged from the riparian runoffs.

关键词： metal enrichment sediments overlying water suspended particles Deep Bay.

Dynamic simulation and modeling of PCP transport between sediment and water

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Journal of Environmental Sciences 1998年第1期10卷 71-77页

作者： Li Tie Ye Chang-ming Lei Zhi-fang Research Center for Eco Environmental Sciences Chinese Academy of SciencesBeijing 100085China

A model to calculate the concentration of organic pollutant in the water column is presented. The inflow, outflow, adsorption of pollutant to the suspended particles and settling of particles, diffusion across the sediment water interface, and volatilization to the atmosphere were considered in this model. Dynamic simulation experiment of pentachlorophenol(PCP) has been made in the laboratory. The model parameters were also estimated with experimental data(diffusion mass transfer coefficient, 0.00112m/d; net settling velocity of particles, 0.323 m.d -1 ; volatilization rate constant, 1.94×10 -4 d -1 ). There are little differences between calculated values and measured values. Adsorption of pollutant to the particles and settling of particles are very important mechanisms for removal of organic pollutant from the water. The principles and methods of this model are also applicable to the prediction of the concentration of other trace elements and organic constituents in aquatic systems.

关键词： dynamic simulation modeling suspended particles PCP transport sediment/water interface.