相关实验视频
Updated: Jan 15, 2026

12:44
Watershed Planning within a Quantitative Scenario Analysis Framework
Published on: July 24, 2016
8.4K
河道几何控制河流中的化学行为:来自比较现场研究的见解
Robert A Newbould1, D Mark Powell1, Juliet Hodges2
1School of Geography, Geology and the Environment, University of Leicester, Leicester LE1 7RH, U.K.
概括
河流的地形学影响了污染物去除. 较小的液压半径的浅河比较深的河流更快地分解污染物,强调需要将道形状纳入环境模型.
科学领域:
- 环境科学环境科学
- 河流生态 河流生态
- 水质管理水质管理.
背景情况:
- 像化和生物降解这样的微生物过程是河流污染物去除的关键.
- 在流中去除速度通常被认为是恒定的,但可能取决于河道的形状和大小,影响水-生物膜接触.
研究的目的:
- 测试污染物转化速率常数是否与河流通道的液压半径 (R) 反比例.
- 调查河流地形学对河流污染物清除效率的影响.
主要方法:
- 使用罗达胺WT的染料追踪实验在英国的两条河流 (马恩河和卡尔德河) 中进行,其中有对比的液压半径.
- 污染物 (糖,,咖啡因,线性硫酸盐) 的速率常量得出.
- 糖被用作一种保守的标记剂,以纠正稀释效应.
主要成果:
- 在较浅的马恩河 (R=1.25m) 与较深的卡尔德河 (R=3m) 相比,观察到生物转化污染物的更高速率系数.
- 结果支持这样的假设,即转换速率常数与液压半径相反相关.
结论:
- 河道地形学显著影响微生物媒介污染物去除的速度.
- 预测河流化学行为的模型应该纳入诸如液压半径之类的地形学因素.
相关概念视频
Typical Model Studies
616
Fluid mechanics model studies often utilize scaled-down systems to predict fluid behavior in full-scale environments, such as river flows, dam spillways, and structures interacting with open surfaces. Maintaining Froude number similarity in river models is crucial, as it replicates surface flow features like wave patterns and velocities.
616
Rapidly Varying Flow
441
Rapidly varying flow (RVF) in open channels is characterized by abrupt changes in flow depth over a short distance, with the rate of depth change relative to distance often approaching unity. These flows are inherently complex due to their transient and multi-dimensional nature, making exact analysis difficult. However, approximate solutions using simplified models provide valuable insights into their behavior.Key Features of Rapidly Varying FlowRVF is commonly observed in scenarios involving...
441
Controlled-Current Coulometry: Overview
640
Controlled current coulometry, also known as amperostatic coulometry, is a technique used in electrochemical analysis to measure the quantity of a substance through the controlled passage of current. It involves the application of a constant current to an electrochemical cell containing the analyte of interest. As the current flows through the cell, the analyte undergoes a redox reaction at the electrode surface, resulting in a charge transfer. By monitoring the time required for a certain...
640
Control Volume and System Representations
1.5K
Two key frameworks are employed to analyze mass, energy, and momentum transfer: the control volume approach and the system approach. These frameworks offer different perspectives, depending on whether the focus is on a specific region in space (control volume approach) or a defined mass of fluid (system approach).
The control volume approach considers a stationary region in space through which fluid flows. This region is bounded by a control surface. For instance, in the case of water...
The control volume approach considers a stationary region in space through which fluid flows. This region is bounded by a control surface. For instance, in the case of water...
1.5K
Conservation of Mass in Moving, Nondeforming Control Volume
1.3K
Stormwater detention basins are essential in managing runoff during heavy rainfall, particularly in urban areas where impervious surfaces increase the risk of flooding. Understanding the conservation of mass in these systems allows engineers to optimize basin performance, balancing inflow, outflow, and water storage.
In the context of a detention basin, the conservation of mass states that the total mass of water entering the basin must equal the mass leaving the basin plus any accumulation of...
In the context of a detention basin, the conservation of mass states that the total mass of water entering the basin must equal the mass leaving the basin plus any accumulation of...
1.3K
Eulerian and Lagrangian Flow Descriptions
1.9K
Fluid flow analysis is critical in many scientific and engineering disciplines, and two principal approaches are used to describe this flow: the Eulerian and Lagrangian methods. These methods offer different perspectives on monitoring and analyzing the motion of fluids, each with distinct advantages depending on the scenario.
The Eulerian method focuses on fixed points in space where fluid properties, such as velocity, pressure, and temperature, are observed as the fluid moves between these...
The Eulerian method focuses on fixed points in space where fluid properties, such as velocity, pressure, and temperature, are observed as the fluid moves between these...
1.9K

