considering the point that the existence of heavy metals in the wastewater are so dangerous forthe environment and it would have many bad consequences for all the creatures including human beings, wemust try out the ways that make us capable of adsorbing these heavy metals. in order to accomplish this goal we should use a method called adsorbing. in this study the adsorption of copper ions in h...

We monitored the water quality and hydrological conditions of a horizontal subsurface constructed wetland (HSSF-CW) in Beijing, China, for two years. We simulated the area-based constant and the temperature coefficient with the first-order kinetic model. We examined the relationships between the nitrogen (N) removal rate, N load, seasonal variations in the N removal rate, and environmental fact...

The fate of ammoniacal-nitrogen (NH4-N) was studied in a lab-scale downflow reed bed system treating an artificial landfill leachate. Individual reed beds were submerged by the leachate, then drained and rinsed by tap water. It was discovered that NH4-N was removed by a two-staged process, adsorption onto the reed bed media followed by nitrification into nitrite-nitrogen (NO2-N) and nitrate-nit...

Treatment with indinavir (IDV), a protease inhibitor, is frequently associated with renal abnormalities. We determined the incidence of renal failure (creatinine clearance <80 mL min-1 1.73 (m(2))-1) in HIV patients treated with highly active antiretroviral therapy, including IDV, and investigated the possible mechanisms and risk factors of IDV nephrotoxicity. Thirty-six patients receiving IDV ...

This laboratory study examined the use of various wood materials as a carbon source in horizontal flow filters to denitrify nitrate-nitrogen (NO3-N) from a synthetic wastewater. The filter materials were: sawdust (Pinus radiata), sawdust and soil, sawdust and sand, and medium-chip wood chippings and sand. Two influent concentrations of NO3-N, 200 mg L(-1) and 60 mg L(-1), loaded at 2.9 to 19.4 ...

Autotrophic denitrification with sulphide using nitrate (R1) and nitrite (R2) as electron acceptor was investigated at bench scale. Different solids retention times (SRT) (5 and 20 d) have been tested in R1 while R2 was operated at SRT=13 d. The results indicated that the process allows complete sulphide removal to be achieved in all tested conditions. Tested sulphide loads were estimated from ...

Abstract. In Arctic ecosystems, increasing temperatures are driving the expansion of nitrogen (N) fixing shrubs across tundra landscapes. The implications this to biogeochemistry ecosystems critical importance and more work is needed better understand form, availability, transportation potential N from these a variety To gain insights into processes controlling within permafrost hillslope syste...

The effect of various salts such as magnesium nitrate, calcium nitrate, zinc nitrate, and magnesium chloride on vapor−liquid equilibrium (VLE) of the ethyl acetate−ethanol system was studied experimentally in a modified Othmer still at atmospheric pressure. The influence of cation and anion of the salts on the VLE of the ethyl acetate− ethanol system was examined. It was observed that the order...

BACKGROUND Nitrate is a drinking water contaminant arising from agricultural sources, and it is a precursor in the endogenous formation of N-nitroso compounds (NOC), which are possible bladder carcinogens. OBJECTIVES We investigated the ingestion of nitrate and nitrite from drinking water and diet and bladder cancer risk in women. METHODS We identified incident bladder cancers among a cohor...