[1] To investigate arsenic mobility in the Bengal Basin groundwater, we sampled water wells and sediments throughout the region. There are strong correlations among high levels of dissolved arsenic and iron, ammonia, and methane, especially in samples from a single site (Laxmipur). No linkage is seen between As and agricultural tracers such as phosphate. The association of As and Fe occurs beca...

Synthetic LAPONITE®-clay particles with platelet-like shape display strong aging when dispersed in aqueous solutions, preventing the latter from reaching their natural liquid-crystalline equilibrium state. Here we introduce a facile method that successfully prevents this aging behaviour and enables accessing the systems' liquid-crystal and crystalline phases. We graft the comb-like polymer PLL-...

Sequential extraction is a useful method of identifying how toxic trace metals bind to soil particles and the strength of these bonds. This is very essential knowledge to reach an efficient soil washing when dealing with remediation of metal-contaminated soil. Sequential extraction uses a succession of extractions on a soil same sample, with extraction liquids expected to promote decreasing mob...

Management of soils to reduce the amount of PM10 emitted during agricultural tillage operations is important for attainment of air quality standards in California's San Joaquin Valley (SJV). The purpose of this study was to improve and expand upon earlier work of predicting tillage-generated dust emissions based on soil properties. We focus on gravimetric soil water content (GWC) and soil textu...

Biodiesel is an attractive alternative fuel because of its nontoxicity and biodegradability properties. Biodiesel is produced through transesterification of vegetable oils’ triglyceride. It is obtained from vegetable oils or fats either by chemical or enzyme-catalyzed transesterification with methanol or ethanol. By using whole-cell biocatalyst immobilized within biomass support particles (BSPs...

We experimentally investigate the rotation of plate shaped aggregates of clay mineral particles immersed in silicone oil. The rotation is induced by an external electric field. The rotation time is measured as a function of the following parameters: electric field strength, the plate geometry (length and width) and the dielectric properties of the plates. We find that the plates always align wi...

The extreme 2010-2011 wet season resulted in highly elevated Burdekin River discharge into the Great Barrier Reef lagoon for a period of 200 days, resulting in a large flood plume extending >50km offshore and >100km north during peak conditions. Export of suspended sediment was dominated by clay and fine silt fractions and most sediment initially settled within ∼10km of the river mouth. Biologi...

A series of montmorillonite-(Ce or Zr) phosphate crosslinked compounds has been synthesized by reaction of a cerium or zirconium cation exchanged montmorillonite (diameter ~2 pm) with phosphoric acid under appropriate conditions of concentration, addition rate and temperature. The materials thus obtained were characterized by chemical and thermal analyses, X-ray diffraction, IR spectroscopy and...

Iron-bearing phyllosilicate minerals help establish the hydrogeological and geochemical conditions of redox transition zones because of their small size, limited hydraulic conductivity, and redox buffering capacity. The bioreduction of soluble U(VI) to sparingly soluble U(IV) can promote the reduction of clay-Fe(III) through valence cycling. The reductive precipitation of U(VI) to uraninite was...

Clay rocks are being considered for radioactive waste disposal, but relatively little is known about the impact of microbes on the long-term safety of geological repositories. Thus, a more complete understanding of microbial community structure and function in these environments would provide further detail for the evaluation of the safety of geological disposal of radioactive waste in clay roc...