查询词典 sediment-covered

In this paper, the researches on sediment transport in sewer are reviewed. Combined with the modeling study on sediment deposition in outfall diffuser, the typical sewer sediment transport functions are analyzed, and functions used in sewer designing are recommended.

对排水管道泥沙运动的研究进行了较为全面的综述，结合相关的排放口扩散器泥沙淤积规律模型试验研究成果，对典型的排水管道泥沙运动方程进行一定分析，提出排水管道设计推荐公式。

In this paper we choose74sediment samples which are from different types of sediment (Loess-paleosol sequence sediment samples, lake sediment samples, Aeolian sand samples, peat and bog samples, Archaeological samples and surface samples). Through our investigations in the laboratory, we have some conclusion about the extraction methods of Quaternary pollen and spores from different type of sediments.

本文选取了中国北方不同沉积相的沉积物样品（黄土与古土壤样品17个、湖泊样品沉积物20个、风成砂样品11个、泥炭沼泽样品10、考古点文化层6个、表土样品10个）共74个，通过对同一种样品不同处理方法的对比研究，就中国北方不同沉积物的孢粉提取方法进行了探讨。

Of coming sediment is deposited in the channel from Datong to Xuliujing; 6.5% of it is deposited in North Branch; a little is eroded hi South Branch from Xuliujing to the mouth; 31% of it is deposited in the submerged delta; 40% of it is deposited hi Hangzhou Bay and its near sea; 4% of it is accreted to land; other sediment is mainly transported to the nearshore of Zhejiang and Fujian coast and thimbleful sediment is diffused into the blue water.

长江来沙10％左右淤积在大通至徐六泾河道，6.5％左右淤积在北支，徐六华东师范大学2001届博土学位论文内容提要 u 径至口门的南支汉道略有冲刷，约 31％淤积在口门以外的水下三角洲，40％淤积在杭州湾及其近海，4％左右泥沙用来塑造陆地和岸线，其它的泥沙，主要沉 '积在浙闽沿海近岸区域，极少量扩散至深海。

Particle-size distribution proved that all the sediment was composed by two parts, a little water-borne sediment and mass wind-borne sediment.

粒度分析试验结果证实了研究区域以风成沉积为主、水成沉积为辅的沉积成因。

The water volume for the sediment transport is most economical on condition that the sediment transport efficiency and the sediment deposition ratio of the watercourse are optimum at the bankfull discharge.

最经济输沙水量是输沙效率与河道淤积状况综合最优时的输沙水量，也就是平滩流量时对应的输沙水量。

The typical local resistance with hyperconcentration sediment are also studied and a method to determine local resistance in sediment pipe is obtained with considering flow intensity and sediment factor.

同时还对典型管道泥浆局部阻力也进行了分析研究，提出了在考虑水流强度、泥沙因子的条件下泥浆局部阻力系数的确定方法。

The results of the present research are as follows, The correlation between physico-chemical properties of organic compounds and their competitive power was studied, and it was indicated that organic compounds preferable to form H-bonding with organic matter of sorbents have stronger competitive power; Sorption behaviors of ionizable organic compounds in different species and their competitive power were examined, and the results showed that phenols and carbonxylic acids with benzyl circle have much stronger competitive power in molecular species than in ionized species, because negative charges of anionic forms can depressed their adsorption on the surface of the sediment; in contrast, organic bases such as aniline and p-chloroaniline show weaker competitive power in molecular species than in ionized species, and this is because both species of the organic bases could adsorb strongly onto the sediment; there is a correlation between competitive power of organic pollutants in multi-solute systems and their sorption isotherm nonlinearity in single-solute systems, and organic compounds whose sorption isotherms is linear in single-solute systems hardly have competitive power in multi-solute systems; Competitive sorption effects in more than two-solutes systems was studied, and it was exhibited that mixture of two cosolutes each of which could suppress sorption of nominal solute onto the sediment had synergistically competitive sorption effect on the nominal solute; A method about incorporating sorption/desorption of organic pollutants into river water quality model was developed, and discussion about degree of sorption/desorption effect on model prediction for different organic compounds was made, which will provide theoretical basis and practical processes for setting up more accurate water quality model.

论文主要取得了以下研究成果。(1)有机化合物的吸附竞争能力与其物化性质具有相关性，易与沉积物有机质形成氢键的化合物其竞争能力也比较强；(2)可离子化有机化合物的吸附竞争能力与其存在形态有关。酚类、含苯环的羧酸类化合物，其离子态的吸附竞争能力远小于分子态，其机理为有机酸阴离子所带的负电荷抑制了表面吸附能力，主要发生分配作用；而苯胺类化合物，其离子态和分子态都表现出显著的竞争能力，而且离子态的竞争能力略强于分子态，原因在于有机碱阳离子所带的正电荷促进了其表面吸附能力；有机化合物竞争能力的强弱与其单组分吸附等温线的非线性程度具有一定的相关性，吸附等温线近似为线性的化合物没有或只具有微弱的竞争能力；(3)对目标有机化合物的吸附具有竞争效应的有机化合物混合后，将对目标有机化合物的吸附产生协同竞争效应；(4)以京杭运河为例，率先提出了将有机污染物的吸附／脱附作用及水文水力参数耦合到水质模型中的方法，并讨论了吸附／脱附作用对不同有机污染物预测模型的影响，为建立更准确的水质模型及进行更客观的风险和生态评估提供了参考依据。

With Yangtze delta tidal flat as an example, through the analysis on the magnetic characteristics of tidal flat sediment and the study on the space distribution of heavy metal elements, this thesis discussed the impact to Shanghai sea bank brought by heavy intensity development, and the interrelation between sediment power effect and heavy metal pollution space distribution. Utilizing the advantage of artificial intelligence neural network, in conjunction with environmental chemical analysis, from the angle of view of sediment magnetic characteristics, it analyzed the connection mechanism between magnetic mines and heavy metal element within tidal sediments, and built a quantitative magnetical diagnosis model, in attempt to calculating the tidal heavy metal pollution status from the magnetic measurement data of sediments and assess it's impact to the environment.

中文题名长江口潮滩重金属污染的磁诊断模型研究副题名外文题名论文作者许羽导师俞立中教授学科专业自然地理学研究领域\研究方向资源与环境信息系统学位级别博士学位授予单位华东师范大学学位授予日期2001 论文页码总数111页关键词长江口潮滩沉积物环境磁学重金属污染馆藏号BSLW /2001 /X145 /11 本文以长江口南岸潮滩为例，通过对潮滩沉积物磁性特征的分析、重金属元素空间分布的研究，探讨了上海滨岸带高强度开发对潮滩环境质量的影响，以及沉积动力作用与重金属污染空间分布格局的联系。

The study area is basically located in hydrodynamic balance belt, and the suspended sediment transport is characteristics of reciprocating movement and small amount of net sediment discharge. The net suspended sediment transport is mainly controlled by average current transport, Stokes drift-induced transport and gravitational circulation transport. The advection transport effect gradually weakens and gravitational circulation transport evidently intensifies from Hangzhou Bay to the offshore area. Settling velocity of single particles is far smaller than that of floccules, so, influence of flocculation of suspended sediments must be taken into the consideration.Incipient velocity and transport flux of surface sediments are analyzed using formulas of incipient velocity and transport flux. Transport trend and controlling factors of surface sediments are studied by the method of grain size trend analysis.

结果表明，研究区净悬沙通量自杭州湾内向外海迅速变小，悬沙总体由杭州湾向外海输运，但同时存在向杭州湾方向的净输沙；研究区基本处于水动力平衡带，悬沙输运具有往复搬运、净输沙量小的特点；平均流输运、Stokes漂移输运和垂向净环流输运是引起悬沙泥沙净输运的主要作用机制，自口门至外海，平流输运作用逐渐减弱，垂向净环流输沙在悬沙净输运中所占比例逐渐增加；舟山群岛海域既是杭州湾向东海输运泥沙的重要通道，也是东海沿岸流携带泥沙向南输运的过渡地带；研究区单颗粒泥沙沉降速度很小，远小于絮凝沉降速度，在研究本区悬沙沉降时必须考虑絮凝的影响。

Prediction of sediment concentration is investigated. Taking Toudaoguai hydrological station as an example, the factors affecting the sediment concentration in the non-freeze-up and freeze-up runoff models are analyzed and the neural network models of sediment concentration prediction are established.

3以黄河头道拐水文站为例对水流日均含沙量的预测进行了研究，在对黄河非凌汛期和凌汛期等不同径流模式下水流含沙量的影响因子进行分析的基础上，分别建立了各径流模式下的水流含沙量的神经网络预测模型。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。