藻类及其分泌物对混凝过程的影响研究

采用纯萍进行烧杯混凝试验，考察了试验藻种及其分泌物对混凝过程的影响，试验发现：藻类对混凝过程的影响与藻的种类，生长阶段及藻浓度有关；一般说来，藻类在浓度较低时，对混凝过程吸不同程度的促进作用，而在高浓度时，对混凝过程有不同程度的干扰。增加混凝剂投加量，调节ｐＨ，耐加氯可以减弱藻类及其分泌物对混凝过程的影响。     

硫化物分析中消除干扰的方法探讨

测定水样中硫化物的含量时，用全下蒸馏器蒸馏法对样品进行预蒸馏处理，可消除干扰，得出较理想的结果。     

白洋淀水体总磷污染分析及防治对策研究

本文分析了白洋淀总磷污染状况，调查了白洋淀总磷的来源，并提出了白洋淀总磷污染的对策与措施。     

沉积物与水间相互作用的研究进展

本文综述了沉积物／水之间的相互作用的研究进展，主要讨论了污染物在沉积物／水界面间的物质传输：水体中污染物在颗粒物上的吸附作用；与沉积物相关的水质，健康和管理等方面的问题。     

小南湖水体中铜锰锌镉的迁移和积累特性

以杭州西湖的子湖（小南湖）的水生生态环境为研究对象，同步分析了水和底泥中重金属的形态分布，以及软体动物和水生植物的重金属的含量，揭示了Ｃｕ、Ｚｎ、Ｃｄ的积累、迁移和转化规律，结果表明：（１）水相中Ｃｕ、Ｚｎ、Ｃｄ主要以溶解态存在，Ｍｎ主要以颗粒态Ｉ存在；底泥中，Ｃｕ主要以有机结合态，Ｍｎ以铁锰氧化结合态，Ｃｄ以碳酸盐态、Ｚｎ以铁锰氧化结合态存在，在水和底泥中，重金属总量次序分别为：Ｚｎ〉Ｍｎ〉Ｃｕ     

有机化合物在水体中生物富集的研究

生物体从周围环境中蓄积某种无素或难分解的化合物,使该物质在体内的浓度超过环境中的浓度,这种现象叫生物富集.在水环境中某些有机污染物在水生生物体内的浓度比水体中的浓度可以高几个数量级,从而造成了这种化合物对于那些以水生生物为食的哺乳动物(包括人类)的高的暴露浓度因此,生物富集过程是进行暴露分析的一个不容忽视的方面,对化合物的生物富集的细致研究也就成为化学品危险性评价的一个必不可少的部分.     

Study on the wind field and pollutant dispersion in street canyons using a stable numerical method

A stable finite element method for the time dependent Navier-Stokes equations was used for studying the wind flow and pollutant dispersion within street canyons. A three-step fractional method was used to solve the velocity field and the pressure field separately from the governing equations. The Streamline Upwind Petrov-Galerkin(SUPG) method was used to get stable numerical results. Numerical oscillation was minimized and satisfactory results can be obtained for flows at high Reynolds numbers. Simulating the flow over a square cylinder within a wide range of Reynolds numbers validates the wind field model. The Strouhal numbers obtained from the numerical simulation had a good agreement with those obtained from experiment. The wind field model developed in the present study is applied to simulate more complex flow phenomena in street canyons with two different building configurations. The results indicated that the flow at rooftop of buildings might not be assumed parallel to the ground as some numerical modelers did. A counter-clockwise rotating vortex may be found in street canyons with an inflow from the left to right. In addition, increasing building height can increase velocity fluctuations in the street canyon under certain circumstances, which facilitate pollutant dispersion. At high Reynolds numbers, the flow regimes in street canyons do not change with inflow velocity.     

Distribution, sources and potential toxicological significance of polycyclic aromatic hydrocarbons(PAHs) in Guanting Reservoir sediments, China

The Guanting Reservoir lost its function as the second biggest drinking water source for Beijing due to the pollutions from the upstream flow of Yongding River in 1997. From 1998, lots of studies were carryied out to renew the function of Guanting Reservoir as domestic drinking water source before 2008 Olympic Games. This is the first time that polycyclic aromatic hydrocarbon concentrations in the surface sediment of Guanting Reservoir have been analyzed. A distinctive spatial distribution of PAHs was observed. Sediments from four sites along Inlet of Yongding River to reservoir bam had PAHs concentrations of 1377--2855 μg/g dw in descending order. The composition of PAHs is investigated and used to assess patrogenic,combustion and naturally derived of the sediments samples of Guanting Reservoir. Special PAHs ratios, such as phenanthrene/anthracene(P/A) and fluoranthene/pyrene(Fl/Pyr) were calculated to assess the relative importance of different origins. The data confirmed a relatively high level of petrogenic contamination in four sites. These high PAHs levels were associated with the input of untreated and partially treated industrial sewage. In addition, the concentrations of PAHs compounds of samples indicated that sediments of reservoir were most likely to pose potential biological impairment.     

Phosphorus removal by the multipond system sediments receiving agricultural drainage in a headstream watershed

Wetland systems in headstream watersheds are important to control the nonpoint source pollutant phosphorus. Experiments were conducted using intact sediment-water columns obtained from the multipond system in Liuchahe watershed of Chaohu Lake to determine its capacity to retain P. It was found that pond sediments had strong P retention ability. For the Hill pond, Village pond and Rice pond, their retention coefficient(A) were 288.3, 279.2 and 260.8 L/m^2, respectively. The equilibrium P concentration(EPCw) were 0.016, 0.028 and 0.018 mg/L, respectively. The Hill pond indicated the highest P retention ability. P retained in the pond sediments indicated high stable degree. P removal from the overlying water column into the pond sediments followed a first-order kinetic model. Under the experimental hydrological conditions, the retention time had a positive correlation with the P loading. The multipond system could provide enough retention time to retain P in drainage runoffs. At the P levels evaluated, the sediments of the multipond system are effective sinks to retain P from nonpoint source runoffs.     

巢湖合肥地区洗衣粉排磷占入湖磷贡献率的研究

合肥地区人均洗衣粉用量为3．12kg/a,洗衣粉总用量为8345t/a,洗衣粉带入水体的总磷量为256．08t/a,占入湖总磷负荷量的13．62％。因此,实行“禁磷”措施后,可削减该地区入湖总磷负荷量的13．62％,对改善巢湖水质将会起到一定的积极作用。