A procedure for the optimization of an unstructured first-order kinetics model of cyclically operated biological reactors for the biodegradation of a single pollutant is developed using a combination of analytical and numerical tools. Asymptotic analytical profiles for the substrate and biomass for each steady cycle are obtained that allows the formulation of an analytical design equation that ...

A nonlinear five-dimensional mathematical model is proposed and analyzed to study the removal of a gaseous pollutant and two different particulate matters by rain from the atmosphere of a city. The atmosphere, during rain, is assumed to consist of five interacting phases namely, the raindrops phase, the gaseous pollutant phase, its absorbed phase and the phases of two different particulate matt...

An allocation scheme of water pollutant reduction is the key procedure to implement a watershed total maximum daily load (TMDL) program. In order to improve the equity for the allocation scheme of water pollutant load reduction, five indexes involved in allocation processes were selected from fields associated with society, environment, economics, and resources. The weights of these indexes wer...

During the flight, aircraft produces several pollutant emissions and the amount is deeply related to the atmospheric conditions (especially pressure, humidity, temperature, air density and wind), the aircraft performance and the phase of flight. In this paper an approach, based on Dijkstra algorithm, to calculate optimized trajectory in terms of several emission reduction (multi-objective traje...

According to the newly introduced water resources management in China, which is the most stringent thus far, pollution limits of water functional zones should be enhanced. In response to this recent change, we propose a provincial initial water rights incentive allocation model with total pollutant discharge constraint. Firstly, three objective functions are set up, namely the maximum comprehen...

The evaluation of pollutant levels is a key aspect on the issue of keeping a clean environment. Conventional techniques include the utilisation of a xed setup incorporating pollutant sensors. However, these approaches are a very long way from an accurate monitoring. Thus, to improve pollutant monitoring on a power plant chimney, the use of robotic agent societies (mobile robots) is suggested. T...

Stormwater quality modeling results are subject to uncertainty. The variability of input parameters is an important source of overall model error. An in-depth understanding of the variability associated with input parameters can provide knowledge on the uncertainty associated with these parameters and can assist in uncertainty analysis of stormwater quality models and decision making based on m...

biodegradation kinetics of 4-nitrophenol (pnp) in aqueous solution by a gram negative soil bacterium, ralstoniaeutropha was firstly studied in a small scale batch reactor. the degradation of pnp was evaluated at initial pnp concentrations ranging from 3 mg/l to 14 mg/l. the rate of pnp consumption by the bacterium culture was modeled using monod and contois kinetics in batch condition. pnp degr...

Nonpoint source (NPS) pollution is considered the main reason for water deterioration, but there has been no attempt to incorporate vertical variations of NPS pollution into watershed management, especially in mountainous areas. In this study, the vertical variations of pollutant yields were explored in the Three Gorges Reservoir Region (TGRR) and the relationships between topographic attribute...