Iron-bearing phyllosilicates strongly influence the redox state and mobility of uranium because of their limited hydraulic conductivity, high specific surface area, and redox reactivity. Standard extraction procedures cannot be accurately applied for the determination of clay-Fe(II/III) and U(IV/VI) in clay mineral-U suspensions such that advanced spectroscopic techniques are required. Instead,...

Naturally occurring clay colloidal particles are heavily involved in sediment processes in the subsurface soil. Due to the importance of these processes in the subsurface environment, the transport of clay colloidal particles has been studied in several disciplines, including soil sciences, petrology, hydrology, etc. Specifically, in environmental engineering, clay colloid release and transport...

Seven current methods of protein quantitation, Bradford (standard, micro, and 590/450 nm ratio), Lowry, bicinchoninic acid (BCA), UV spectrophotometry at 280 nm, and Quant-iT fluorescence-based determination, were compared with regard to their susceptibility to interferences due to the presence of suspended and not easily detectable clay particles. Bovine serum albumin (BSA) and Na-Wyoming mont...

I N T R O D U C T I O N T h e s t u d y o f c lay f o r m a t i o n i n soils m a y b e d i v i d e d i n t o t h r e e p a r t s : (1) a q u a n t i t a t i v e e v a l u a t i o n o f t h e a m o u n t o f c lay f o r m e d f r o m a g i v e n a m o u n t o f p a r e n t m a t e r i a l , (2) a q u a l i t a t i v e e v a l u a t i o n of t h e k i n d o f m i n e r a l s a n d o t h e r s u ...

Smectites or swelling clay minerals are naturally occurring nanomaterials that can be fully delaminated to elementary clay mineral platelets in dilute aqueous dispersion. This review article gives an overview of the recent progress on how the elementary clay mineral platelets can be reorganized in monolayered or multilayered hybrid nanofilms by layer-by-layer assembly or the Langmuir-Blodgett t...

-The addition of a 10% talc internal standard to North Pacific sediments allows the relative abundances of clay minerals to be determined both accurately and precisely by X-ray powder diffractometry. Linear programming can be used to generate factors for converting talc-normalized peak areas to weight percentages; hence, absolute clay-mineral abundances can be estimated. This procedure minimize...

OBJECTIVE To understand the significance of clay art therapy for psychiatric patients admitted in a day hospital. METHODOLOGY Qualitative, descriptive and exploratory research, undertaken with 16 patients in a day hospital in Londrina, in the state of Parana, Brazil, who participated in seven clay therapy sessions. Data collection took place from January to July 2012 through interviews guided...

Simulated through a 3D grid storing the density of clay in each cell (0 for an empty cell, and 1 for a full cell). The surface is defined as the iso-surface at 0.5 of clay density. Clay behavior is captured by a layered model ensuring 3 properties: Large scale deformations (fig.1) Mass conservation by pouring the excess of matter in neighbouring cells (fig.2) Surface tension for preventing the ...

The spatial organisation of swelling clay platelets in a suspension depends on the chemical composition of the equilibration solution. Individual clay platelets can be well dispersed, with surfaces entirely in contact with the external solution, or be stacked in tactoids, where part of the surfaces forms parallel alignments embedding interlayer water and cations. External and interlayer surface...

Besides having a large capacity for taking up organic molecules, clay minerals can catalyze a variety of organic reactions. Derived from rock weathering, clay minerals would have been abundant in the early Earth. As such, they might be expected to play a role in chemical evolution. The interactions of clay minerals with biopolymers, including RNA, have been the subject of many investigations. T...