共查询到20条相似文献，搜索用时 390 毫秒
1.
2.
ＳＴＵＤＹＯＮＴＨＥＭＡＴＨＥＭＡＴＩＣＡＬＭＯＤＥＬＯＦＨＥＡＶＹ－ＭＥＴＡＬＰＯＬＬＵＴＡＮＴＴＲＡＮＳＰＯＰＴ－ＴＲＡＮＳＦＯＲＭＡＴＩＯＮＩＮＲＩＶＥＲＳ￥Ｓｕｉ－ｌｉａｎｇＨｕａｎｇａｎｄＺｈａｏ－ｈｕｉＷａｎ（ＰｏｓｔｄｏｃｔｏｒａｌＦｅ... 相似文献
3.
ＳＴＵＤＹＯＮＲＥＣＨＡＲＧＥＯＦＧＲＯＵＮＤＷＡＴＥＲＳＡＮＤＩＮＴＥＲＲＥＬＡＴＩＯＮＳＢＥＴＷＥＥＮＶＡＲＩＯＵＳＷＡＴＥＲＳＢＹＭＥＡＮＳＯＦＥＮＶＩＲＯＮＭＥＮＴＡＬＩＳＯＴＯＰＥＳ￥ＳｅｖｉｌＧｕｌｅｒ；ＥｒｇｕｎＤｅｍｉｒｏｚ（Ｓｐｅｃ... 相似文献
4.
ＭＡＴＨＥＭＡＴＩＣＭＯＤＥＬＡＮＤＥＸＰＥＲＩＭＥＮＴＡＬＳＴＵＤＹＯＮＡＤＳＯＲＢＩＮＧＯＩＬＢＹＳＥＤＩＭＥＮＴＷｅｎｑｉａｎＺＨＡＯ１ａｎｄＸｉａｏｂｏＣＡＯ２ａｎｄＱｉｎｓｈｅｎｇＨＵＡＮＧ３ＡＢＳＴＲＡＣＴＴｈｅｃｈａｒａｃｔｅｒｉｓｔ... 相似文献
5.
ＳＯＩＬＳＣＯＵＲＲＥＳＩＳＴＡＮＣＥＡＮＤＡＲＲＡＮＧＥＭＥＮＴＯＦＳＯＩＬＡＮＤＷＡＴＥＲＣＯＮＳＥＲＶＡＴＩＯＮＳＹＳＴＥＭＩＮＴＨＥＣＯＮＴＩＧＵＯＵＳＡＲＥＡＯＦＳＨＡＮＸＩ,ＳＨＡＡＮＸＩＡＮＤＩＮＮＥＲＭＯＮＧＯＬＩＡ１ＪＩＡＮＧＤｉ... 相似文献
6.
ＴＨＥＲＩＶＥＲＣＨＡＮＮＥＬＡＤＪＵＳＴＭＥＮＴＡＳＩＮＦＬＵＥＮＣＥＤＢＹＴＨＥＦＬＯＯＤＰＬＡＩＮＧＥＯＥＣＯＳＹＳＴＥＭ：ＡＮＥＸＡＭＰＬＥＦＲＯＭＴＨＥＨＯＮＧＳＨＡＮＲＥＳＥＲＶＯＩＲ￥ＸＵＪｉｏｎｇｘｉｎ；ＳＨＩＣｈａｎｇｘｉｎｇ（Ｐｒ... 相似文献
7.
ＵＮＣＥＲＴＡＩＮＴＹＡＮＤＳＥＮＳＩＴＩＶＩＴＹＡＮＡＬＹＳＥＳＯＦＳＥＤＩＭＥＮＴＴＲＡＮＳＰＯＲＴＦＯＲＭＵＬＡＳＫｅｈＣｈｉａＹＥＨ１ａｎｄＳｅｎＬｏｎｇＤＥＮＧ２ＡＢＳＴＲＡＣＴＩｎｖｉｅｗｏｆｔｈｅｒａｎｄｏｍｃｈａｒａｃｔｅｒｉｓｔ... 相似文献
8.
9.
YANG Guowei 《国际泥沙研究》1994,(2)
ＳＴＵＤＹＯＦＭＥＴＨＯＤＯＬＯＧＹＦＯＲＰＨＹＳＩＣＡＬＭＯＤＥＬＩＮＧＯＦＳＥＤＩＭＥＮＴＡＴＩＯＮＩＮＲＥＳＥＲＶＯＩＲＹＡＮＧＧｕｏｗｅｉ（ＴｈｅＥｎｇｌｉｓｈｔｅｘｔｈａｓｂｅｅｎｒｅｖｉｅｗｅｄｂｙＭｒ．ＣＡＩＸｉａｏｙｏｎｇａｎｄｅｄｉ... 相似文献
10.
ＷＡＴＥＲＱＵＡＬＩＴＹＳＩＭＵＬＡＴＩＯＮＯＦＨＥＡＶＹＭＥＴＡＬＴＲＡＮＳＰＯＲＴＡＴＩＯＮＩＮＴＨＥＹＥＬＬＯＷＲＩＶＥＲＳＨＥＮＸｉａｎｃｈｅｎ１,ＦＥＮＧＨｕｉｈｕａ２,ＷＡＮＧＦｅｎｇｒｏｎｇ３ａｎｄＬＩＵＬｉｎｈｕａ４ＡＢＳＴＲＡＣＴＡ... 相似文献
11.
Periáñez R 《Marine pollution bulletin》2012,64(2):221-232
An environmental study of Algeciras Bay is carried out through numerical modelling. First, a 2D barotropic model is applied to calculate tides and mean circulation. Results of this model are used by a sediment transport model which provides suspended matter concentrations and sedimentation rates in the Bay. It includes three particle classes. An effective diffusion coefficient has been calibrated simulating temperature distribution inside the Bay. An additional validation is obtained from an independent nitrate dispersion simulation. Then heavy metal dispersion patterns are investigated using a model which includes water-sediment metal interactions and uses the outputs of the hydrodynamic and sediment transport models. The metal transport model has been applied to simulate the dispersion of Zn, Cu and Ni. Results from the hydrodynamic, sediment and metal transport models have been compared with measurements. Model results also indicate that transport inside the Bay is relatively weak. Numerical experiments have been carried out to determine flushing times for conservative and non-conservative pollutants. Flushing time is about 20 days for a conservative tracer, and this value is mainly due to the M(2) residual current. Tides are not effective in removing pollutants. 相似文献
12.
13.
Onyx W. H. WAI 《国际泥沙研究》2009,24(4):425-438
The so-called fine sediment in many coastal areas and estuaries in China is mostly referred to the mixture of cohesive sediment and non-cohesive sediment. To predict the mixed type time sediment transport, sediment carrying capacity formulae combined with the 2-D suspended sediment transport equation and morphologic equation have been widely used in China. In the present study, the sediment carrying capacity formula suggested by Dou et al. （1995） for wave conditions has been improved and implemented for the prediction of sediment transport in nearshore regions where wave activities are significant. The improvement is based on the wave energy dissipation principle inside and outside the surf zone. In the improved formula, sediment in suspension increases with the magnitude of the wave period and this feature complies with general observations. More than 300 laboratory and field measured data sets have been reviewed and 12 of them have been used to verify and determine the major coefficients in the improved formula. The application of the sediment carrying capacity model in combined wave and current situations shows that the model can faithfully reproduce the cross-shore sediment concentration distributions at the southwest coast of Bohai Bay. 相似文献
14.
贵州红枫湖沉积物磷赋存形态及沉积历史 总被引：38，自引：4，他引：34
采集了云贵高原深水湖泊红枫湖现代沉积物未受扰动的柱状样品,通过分析不同形态沉积磷在沉积剖面上的分布特征,并结合沉积物样品柱的210Pb、137Cs年代学研究结果,揭示了红枫湖现代沉积过程中不同形态沉积磷的早期成岩改造的时间变化序列,以及沉积磷外源输入负荷的历史变化.采用Ruttenberg法分析沉积磷的地球化学赋存形态,研究表明,红枫湖沉积物中有机磷和铁结合态磷是沉积磷的主要赋存形态,分别占沉积全磷的60%和28%.沉积磷在垂直剖面上的分布特征显示,红枫湖现代沉积过程中,沉积磷在最终埋藏前可能发生非常剧烈的形态转化和再迁移,尤其是有机磷和铁结合态磷的成岩改造可能是湖泊系统磷循环质量平衡的重要方面.年代学数据同时表明,近年的人为活动导致湖泊系统(包括沉积物)磷负荷的显著增加. 相似文献
15.
Kalundborg Fjord is a Danish marine area which has been heavily oil polluted by refinery effluent, leading to accumulation of petroleum hydrocarbons in the surface sediments. A study of the occurrence in the sediment of heterotrophic bacteria, yeasts and filamentous fungi has been carried out, and the physiological composition of the microbial community has been recorded. Though the abundance of oil-degrading microorganisms was significant, a correlation between the number of these and the oil content of the sediment could not be demonstrated. 相似文献
16.
V. N. Mikhailov 《Water Resources》2010,37(2):145-159
The regime and budget of water and sediment runoff in the mouth area of the Amazon River are discussed. New values of the
water and sediment runoff at the terminal cross section (the town of Obidos) and at its outflow into the Atlantic Ocean have
been obtained on the basis of observational data. It turned out that the water runoff value was markedly higher and the sediment
runoff value was lower than it had been considered previously. 相似文献
17.
The paper presents the results of a study in which the uncertainty levels associated with a detailed and a simplified/parsimonious sewer sediment modelling approach have been compared. The detailed approach used an Infoworks CS sewer network model combined with a user developed sediment transport code and the simplified approach used a conceptual sewer flow and quality model. The two approaches have been applied to a single case study sewer network and the simulation results compared. The case study was selected as moderate storm events had occurred during a 2 year rainfall and sewer flow monitoring period. Flooding had been observed and this was thought to be caused by significant solids accumulation in the sewer network. As a result sediment deposit measurements were carried out over a 6 month period. Model simulations were made of this period and predictions obtained of sediment deposit location and depth. The uncertainty analysis of both modelling approaches was carried out using Monte Carlo based computational methods. This was a limitation for the detailed approach with regards to computational time. Use of the simplified model was not constrained by this issue and so a more conventional assessment of the uncertainty was possible. The simplified approach, due to its structure, only provided a temporal estimate of uncertainty at the final section of the catchment. The detailed approach enabled an assessment of uncertainty at an individual pipe scale but only at the end of the simulation period. A comparison of the uncertainty estimations from both methods at the final section of the catchment and the end of the simulation period indicated comparable values of predicted uncertainty. Therefore a complementary use of both approaches would allow reasonably comparable estimations of levels of uncertainty at both a spatial and temporal scale. The use of such modelling approaches may provide a useful decision-making tool for sewer system management. 相似文献
18.
Flume experiments were carried out to study the turbulence and its impact on suspension and segregation of grain-sizes under unidirectional flow conditions over the sand-gravel mixture bed. The components of fluid velocity with fluctuations were measured vertically using 3-D Micro-acoustic Doppler velocimeter (ADV). The theoretical models for velocity and sediment suspension have been developed based on the concept of mixing length that includes the damping effect of turbulence due to sediment suspension in the flow over the sand-gravel mixture bed. Statistical analysis of segregation of grain-sizes along downstream of the bed has been performed using the principle of unsupervised learning or clustering problem. Exploratory data analysis suggests that there is a progressive downstream fining of sediment sizes with selective depositions of gravels, sand-gravels and sand materials along the stream, which may be segmented into three regions such as, the upstream, the transitional and the downstream respectively. This contribution is relevant to understand the direction of ancient rivers, the bed material character in the river form, sorting process and its role in controlling the sediment flux through landscape. 相似文献
19.
The interaction among tidal currents, sediment transport, and long-term changes of the sea bottom in the Colorado River Delta
have been investigated applying a two dimensional nonlinear hydrodynamic-numerical finite differences model. The system was
forced by the dominant M
2 tidal component at the open boundary. We carried out calculations to study the morphodynamics of the actual bathymetry caused
by the bedload sediment transport. To investigate the origin of actual morphological features, we performed experiments using
a smoothed bathymetry, in which the islands Montague, Gore, and Pelícano were eliminated. Under the imposed tidal hydrodynamics,
the results indicate that the bedload transport contributes significantly in the genesis of sandbanks and in the formation
and maintaining of the Montague and Gore Islands. 相似文献
20.
Understanding coarse sediment transport is crucial for the prediction of sediment migration and the consequent development of fluvial morphologies. In this study, cobble displacements in a pre-Alpine creek have been recorded by means of radio frequency identification (RFID). Pebble monitoring has been systematically performed after each rainfall event with moderate precipitation, in order to exclude the superimposition of sediment displacements induced by triggering factors acting at different times. The analysis of the collected data was carried out through the application of both a principal component analysis and the Buckingham Π theorem. The experimental trends were interpreted considering the ratio of mobile pebbles, the pebbles' displacement and virtual velocity as the dependent variables. These quantities mostly depend on the event peak discharge, with a nonlinear increase of the travelled distance and a growth of up to two orders of magnitude of the virtual velocity (for an approximately 10× increase in peak discharge). An inverse dependency of the virtual velocity on the event duration was also observed. A comparison of the results obtained with those from laboratory investigations of bedload transport mechanics evidenced the differences in parametric trends associated with sediment mobility in the two environments. This contrast brings forward the combination of multiple drivers of sediment mobility, such as local morphology, sediment dimensions and flow unsteadiness, warranting a further in-depth investigation. Representation of results in a dimensionless form is suggested as a good practice to analyse data from case studies characterized by different scales. © 2019 John Wiley & Sons, Ltd. 相似文献