Aeration of some sort is frequently provided during laboratory cultivation of bacteria. Since metabolic responses and the nature of fermentation products may depend upon the amount of available oxygen (Pirt, 1957), it is important to have some adequate measure of this variable. Finn (1954) has pointed out that gassing rates alone are without significance; it is necessary to determine the rate a...

The aeration process via injectors is used to combat the lack of oxygen in lakes due to eutrophication. A 3D numerical simulation of the resulting flow using a simplified model is presented. In order to generate the best dynamic in the fluid with respect to the aeration purpose, the optimization of the injectors location is considered. We propose to adapt to this problem the topological sensiti...

abstract aeration is conducted on the perennial grasses such as lawns to reduce soil compaction and enhances the growth as well as improves soil infiltration. in order to evaluate the effects of aeration and topdressing on water infiltration phenomenon in a perennial lawn a factorial experiment in a completely randomized design was conducted in the city of isfahan in june 2009. aeration, as the...

Activated sludge process is a highly effective and commonly adapted method of aerobic biological treatment systems and is normally designed on the basis of simplified hydraulic related parameters. Designs of biological treatment systems based on hydraulic considerations are not adequate to ensure efficient operation. This is due to the wide variation in the composition of wastewater and the com...

The soil fauna plays an important function over the processes of organic matter decomposition, nutrient cycling, ground aeration and fertility. Thus, studies on the composition and structure of such communities are important, considering moreover the lack of information in different regions of Brazil and mainly related to the state of Piauí. This study aimed to evaluate the density and diversit...

This study describes the biological degradation of TNT by using induced aeration. Three plastic reactors were used. In each reactor 3 kg of soil were used. In order to increase the porosity of the soil, sawdust was added to soil. Textile wastewater treatment plant sludge was also added to soil. TNT at the concentrations of 1000 mg/kg of soil was added thereafter. Rhamnolipid biosurfactant at th...

To upgrade some conventional aeration processes, a lab-scale system for promoting nitrogen and phosphorus removals was set up and studied through a series of experiments, in which water hyacinth was planted on the surface of the mixed liquor in aeration tanks. The main purpose of this study was to evaluate the effects of (1) aeration, (2) organic load (chemical oxygen demand) and (3) residence ...

With the re-evaluation and revision of a number of design floods, several embankment overtopping protection systems have been developed and a common technique is the construction of a stepped spillway on the downstream slope. For such moderate slope stepped channels, detailed air–water flow measurements were performed in a large facility with a focus on the rate of energy dissipation, flow resi...

A web-based model was used to simulate the impact of aeration on population growth of the lesser grain borer, Rhyzopertha dominica (F.), and the rice weevil, Sitophilus oryzae (L.), in stored rough rice, Oryza sativa L., at Beaumont, TX. Simulations were run for each of 10 yr with 1 August as the start date; 31 December as the end date; beginning populations of 2.5 adults per metric ton (1000 k...