In aquatic environments, phosphorus is known as the “limiting nutrient.” It combines with nitrogen and photosynthetic processes to produce plant and algal growth. Phosphorus in marine life support systems exists in either a particulate or dissolved phase. While particulate sources may be removed during filtration or fractionation, the dissolved form persists. In a typical marine environment (pH...

The activated sludge process is commonly used to treat wastewater by aerobic oxidation of organic pollutants into carbon dioxide and water. However, several nonoxidative mechanisms can also contribute to removal of organics. Sorption onto activated sludge can remove a large fraction of the colloidal and particulate wastewater organics. Intracellular storage of, e.g., polyhydroxyalkanoates (PHA)...

Addition of halogens or halides has been reported to promote mercury removal in coal-fired power plants. In this study, benchand pilot-scale experiments were conducted using potassium iodide (KI) for capture and removal of Hg in air and coal combustion exhaust. Two bench-scale reactor systems were used: (1) a packedbed reactor (PBR) packed with granular or powder KI and (2) an aerosol flow reac...

A new chemistry module that simulates atmospheric ammonia (NH3) and ammonium (NH + 4 ) was incorporated into a backward-in-time stochastic Lagrangian air quality model (STILT-Chem) that was originally developed to simulate the concentrations of a variety of gas-phase species at receptors. STILT-Chem simulates the transport of air parcels backward in time using ensembles of fictitious particles ...

background & aims of the study: nitrogenous compounds could directly create many problems for human's health and the environment. thus, removal of nitrogenous compounds is necessary. among the most important problems, decreasing dissolved oxygen, toxicity for aquatics, eutrophication, converting aerobic medium into anaerobic one and corrosion could be noted. the aim of this study was deter...

This study highlights the behaviour of Mercury in the abiotic and biotic segments of the Mandovi-Zuari estuarine system. Spatial, seasonal (Premonsoon and Postmonsoon) and tidal, distribution of THg in dissolved/particulate fractions, sediment concentrations were mapped of the river mouths, Mormugao Port, inner and outer environs of this estuarine system. Observed seasonal partition studies pro...

One of the principal components of the contaminant load in urban stormwater runoff is oil and grease (O&G) pollution, resulting from vehicle emissions. A mulch layer was used as a contaminant trap to remove O&G (dissolved and particulate-associated naphthalene, dissolved toluene, and dissolved motor oil hydrocarbons) from a synthetic runoff during a bench-scale infiltration study. Approximately...

A low cost, battery-operated, portable, real-time aerosol analyzer is not available for monitoring diesel particulate matter (DPM) concentrations in underground mines. This study summarizes a field evaluation conducted at an underground limestone mine to evaluate the potential of the TSI AM 510 portable photometer (equipped with a Dorr-Oliver cyclone and 1.0-mum impactor) to qualitatively track...

This paper reviews the present state of knowledge on environmental issues related to bivalve aquaculture, with emphasis on suspended mussel culture. Material reviewed includes Canadian and international studies on the role of wild and cultured bivalve populations in controlling ecosystem-level dynamics. The focus is on identifying potential changes in ecosystem processes (material and energy fl...

A particulate fraction of Erysipelothrix rhusiopathiae cultures has been subjected to butanol extraction and treatment with surface-active agents in an attempt to solubilize a protective antigen. The particulate fraction was partitioned into the butanol layer but was not solubilized. Only sodium dodecyl sulfate solubilized the particles. The soluble protective activity was not sedimented by cen...