Deammonification represents a short-cut in the N-metabolism pathway and comprises 2 steps: about half the amount of ammonia is oxidised to nitrite and then residual ammonia and nitrite is anaerobically transformed to elementary nitrogen. Implementation of the pH-controlled DEMON process for deammonification of reject water in a single-sludge SBR system at the WWTP Strass (Austria) contributed e...

Divalent Mn ions cause an increase in the level of phenylalanine ammonia-lyase in gherkin hypocotyls. With the exception of Mg ions, which had a small effect, no other metal ion has so far been found which could replace the Mn ion in this respect. Invertase and peroxidase were not significantly affected by the Mn treatment. The increase in phenylalanine ammonialyase activity is explained by the...

Novel nitrogen removal technologies via nitrite pathway attract increasing interest in recent years. In this study, batch experiments were performed to investigate nitrite accumulation characteristics and shifts in nitrifying community structure at different growth environments including ammonia concentration, pH and alkalinity. It was found that nitrite accumulation ratios were maintained at a...

For long, ammonia has been branded as a harmful acid pollutant causing irreversible damage to the environment. Unlike other pollutants like nitrogen oxides (NOx) and sulphur oxides (SOx), ammonia causes acidification to the environment in a more complex and indirect way. The sequence of reactions between ammonia and acidic aerosols followed with microorganisms to form acidic HNO3 has been well ...

The performance of an aerobic membrane-coupled bioreactor (MBR) operating at mesophilicthermophilic transitional temperatures (40 ̊C) treating oily rendering wastewater has been evaluated in terms of COD, BOD5, oil and grease, solids and ammonia removal at 5 and 10-day HRT. The COD removal efficiency increased from 78% to 96%, BOD5 removal from 87 to 99% and oil and grease removal from 92 to 95%...

The collecting duct is the primary site of urinary ammonia secretion; the current study determines whether apical ammonia transport in the mouse inner medullary collecting duct cell (mIMCD-3) occurs via nonionic diffusion or a transporter-mediated process and, if the latter, presents the characteristics of this apical ammonia transport. We used confluent cells on permeable support membranes and...

Changes in the fractions of ammonia-oxidizing bacteria and nitrite-oxidizing bacteria in two laboratory-scale reactors were investigated using 16S rRNA probe hybridizations. The reactors were operated in intermittent aeration mode and different aeration cycles to treat anaerobically digested swine wastewater with ammonia concentrations up to 175 mg NH(3)-N/L. High ammonia removals (>98.8%) were...

Ammonium was injected from the subseafloor hydrothermal system at the Endeavour Segment, Juan de Fuca Ridge, into the deep-sea water column resulting in an NH4 þ-rich (6177 nM) neutrally buoyant hydrothermal plume. This NH4 was quickly removed by both autotrophic ammonia oxidation and assimilation. The former accounted for at least 93% of total net NH4 þ removal, with its maximum rate in the ne...

Ammonia-nitrogen uptake by seaweed was modeled based on the concept of ammonia-nitrogen permeation through cell membrane, and the derived model of uptake rate was experimentally verified. In this study, sterile Ulva sp. was employed as seaweed to treat model culture solution, and the distribution equilibrium of the ammonia-nitrogen between the culture solution and cell inside was measured to ob...

Approximately three fourths of the ammonia content of whole blood is contained in the red cells and one fourth in the plasma of normal subjects. As shown previously, the ammoniat concentration of erythrocytes is normally about three times that of plasma.' Significant differences from the normal distribution occur, however, in patients with anemia or elevated blood ammonia levels.! Elevations in...