Organic-rich Carboniferous shales with associated coal seams, from the Bacia Carbonífera do Douro-Beira (north Portugal), have been studied by TEM as well as by a variety of other methods. NH4 and K micas and berthierine form small subparallel packets of a few layers separated by lowangle boundaries. Oneand two-layer ordered polytypes, with some spot enlargement typical of minor disorder, occur...

A total of 61 PM10 samples in Huangshi (HS), Central China, were collected every sixth day from April 2012 to March 2013 and were analyzed for water-soluble inorganic ions (WSIIs) by ion chromatography. The sum of three major ions (SO4, NO3, and NH4) accounted for 75.8% of the total WSIIs on average. The results of a non-parametric test (Kruskal-Wallis) show that, except for Na+ (p > 0.05), the...

The century-old trickling filters at the Daspoort Wastewater Treatment Works in Pretoria (Gauteng, South Africa) are known for their remarkable removal of nitrogen from municipal wastewater. Our study was conducted to identify the microbiological processes responsible for this phenomenon and to establish whether anammox bacteria may be involved. An aerobic and anaerobic bench top reactor, both ...

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 present lab-scale research reveals the potential of implementation of an oxygen-limited autotrophic nitrification-denitrification (OLAND) system with normal nitrifying sludge as the biocatalyst for the removal of nitrogen from nitrogen-rich wastewater in one step. In a sequential batch reactor, synthetic wastewater containing 1 g of NH4+-N liter-1 and minerals was treated. Oxygen supply to ...

Selenomonas ruminantium was found to possess two pathways for NH4+ assimilation that resulted in net glutamate synthesis. One pathway fixed NH4+ through the action of an NADPH-linked glutamate dehydrogenase (GDH). Maximal GDH activity required KCl (about 0.48 M), but a variety of monovalent salts could replace KCl. Complete substrate saturation of the enzyme by NH4+ did not occur, and apparent ...

Appropriate and simple analysis methods for an accurate estimation of soil N mineralization potential are required to optimize N fertilizer recommendations. We used soils from non-cultivated and cultivated plots in central Côte d’Ivoire to investigate the quantum of ammonium (NH4 ) that could potentially be mineralized. The soil was first treated with H2O2 at 60°C for 2, 4, 6 or 8 h (and referr...

Uptake of nutrients and organic C was measured once annually between 2000 and 2002 in each of 10 streams within the water-supply source areas for New York City. Nutrients (PO4 3– and NH4 þ) and organic C (glucose and arabinose) were injected into the streams for 1 to 2 h, and uptake lengths were estimated from the longitudinal declines in downstream concentration relative to that of a conservat...