... Aquifer above normal background levels and instead attribute nitrate to recent urban development directly over the aquifer’s recharge zone. Quarries are known to be sources of nitrate pollution of groundwater resulting from use of ammonium nitrate fuel–oil (ANFO) mixtures as explosives in mining...

... activity, corroborated by characteristic ammonium and nitrate ions and a linear relation between chargeability and subsurface temperature. Temperature variations between the aerobic and anaerobic reaction zones ( > 20 ° C and ≤ 12 ° C ) are observed to correlate with high chargeability values...

...Haotian Su; Yingchun Zhang; Jinhong Zhou; Qingfeng Hou Abstract Dodecyl dimethyl benzyl ammonium (DDBA) is a novel cation surfactant used to modify clay minerals. DDBA-intercalated montmorillonite is formed by the ion exchange between DDBA cations in the solution and cations in the montmorillonite...

...Ángel Crespo López; Carlos Pimentel; Carlos M. Pina Abstract The uncommon association of ammonium sulfates identified in the Pastora abandoned mine is the result of a complex mineral evolution. By means of dissolution-(re)crystallization reactions operating during long periods of time, ammonium...

...R. A. P. Thomas; M. J. Riding; J. D. F. Robinson; S. J. A. Brown; C. Taylor Abstract Ammonium is a common contaminant found in the soils and groundwater at former gasworks, associated with historical gas production and the storage and disposal of by-product. However, it can also be present...

...Mohammad Nuruzzama; Tariq Ejaz; Rahul Mohan Abstract Ammonium (NH 4 + ) accumulation and variability in Antarctic ice cores possess signals of various biological, anthropogenic, and atmospheric processes. However, the use of NH 4 + variability in Antarctic ice cores for paleoclimate reconstructions...

... 31 08 2020 17 06 2021 Copyright © The Author(s), 2021. Published by Cambridge University Press on behalf of The Mineralogical Society of Great Britain and Ireland 2021 The Author(s) activation temperature interlayer spacing quaternary ammonium salt sericite mica silane...

... nutrient recycling under anoxic conditions. Here, we show how hydrothermal fluids acted as a recycling mechanism for ammonium (NH 4 + ) in the Archean ocean. We present elemental and stable isotope data for carbon, nitrogen, and sulfur from shales and hydrothermally altered volcanic rocks from the 3.24 Ga...

...Keiko Hattori; Anna Fonseca; Tabetha Sheppard Abstract Rhyolitic rocks hosting the El Zapote epithermal Ag deposit are pervasively altered and contain ammonium ranging from 290 to 1750 ppm. High ammonium values are found in samples containing abundant fine-grained illite. This fine-grained illite...

...Uri Shuali; Shlomo Nir Abstract The present report is a review of uses of quaternary ammonium cations (QACs) as free monomers or immobilized in micelle-clay complexes in bacteria removal from water. The removal of bacteria from water by filtration through a bed of a granulated QAC-clay micelle...

... drastically on zeolite. The cesium desorption from the layered minerals was promoted by the addition of ammonium ions, namely trioctylmethylammonium chloride and zephiramine. These ammonium ions desorb cesium from the interlayers of the minerals without destroying the mineral structure. The cesium desorption...

...Blanca Bauluz; Fernando Nieto ABSTRACT The present study examines the micro- and nano-texture and composition of ammonium-bearing and potassium micas in very-low grade metamorphic black Silurian shales from the SE Iberian Range (NE Spain). Two organic-rich shales were studied by X-ray diffraction...

... that had been dried by heating at 105°C for 24 h and with KBr powder that was dried by heating at 550°C for 24 h. After the collection of FTIR spectra, the pellets were heated again at 150°C overnight and second sets of spectra were collected. Ammonium Illite Dioctahedral Vermiculite Early...

... existed between bilayer and pseudo-trimolecular layer states from C 11 to C 14 . The ammonium groups had two locations: most ammonium groups were located over the six-member rings (~90%), and the rest above the substitution sites (~10%). The ammonium groups interacted with the vermiculite surface through...

... compounds in groundwater in the Sagittario River basin, central Italy. The detrimental effect of the groundwater ammonium on the meiofaunal organisms is also evaluated in the hyporheic zone, where N-NH 4 + concentrations reach a maximum value of 0.6 mg L −1 . The main source of the nitrogen contamination...

..., adsorbable halogenated organic compounds and heavy metals. Among the cations, ammonium (NH 4 + ), which is produced mainly by bacterial degradation, is present to excess ( Lo, 1996 ; Kruempelbeck & Ehrig, 1999 ; Kjeldsen et al. , 2002 ; Öman & Junestedt, 2008 ; Van Nooten et al. , 2008...

... NH 4 + = 1400 pm; phengite NH 4 + = 700 ppm; tourmaline NH 4 + = 500 ppm). Nitrogen cycling nitrogen isotopes ammonium microporous silicate isotope fractionation layer silicates cordierite Review article Invited Centennial article It is often thought that Earth nitrogen (N...

... was assessed for pore-water extraction (e.g., nitrate, ammonium) and solid phase treatment, and the last core from each station was processed for foraminiferal investigation. Bottom seawater was collected in Niskin bottles installed on a rosette system equipped with a CTD (Conductivity, Temperature...