A conventional liner with a good performance against inorganic contaminants with a minimal hydraulic conductivity does not usually perform well for retention/removal of leachates containing organic contaminants. Organic modification of clay can render the naturally organophobic clay to be organophilic. Incorporation of modified organo clay along with unmodified inorganic clay in liner systems c...

Molecular dynamics simulations together with micromechanics method have been proven an effective approach to assess the elastic moduli of either partially or fully exfoliated (i.e. single-layer) effective clay (montmorillonite) cluster. In this work, similar approach was adopted to estimate the overall compressive modulus of nylon 6/montmorillonite nanocomposites. In detail, the compressive mod...

We investigated the mechanical, swelling, and structural properties of mechanically tough clay/sodium polyacrylate (PAAS) hydrogels prepared by simple mixing. The gels had large swelling ratios, reflecting the characteristics of the constituent polymer. The swelling ratios initially increased with the increase of the swelling time, and then attained maximum values. Afterwards, they decreased wi...

The free-radical polymerization of acrylamide in aqueous clay dispersions and the structure of the resulting polymer-clay nanocomposite hydrogels have been investigated by rheometry using oscillatory deformation tests. Laponite was used as clay particles in the hydrogel preparation. The reactions were carried out with and without the presence of the chemical cross-linker N,N′-methylenebis(acryl...

A new approach was developed for reducing leaching of herbicides and contamination of groundwater. Liposome-clay formulations of the anionic herbicides sulfometuron and sulfosulfuron were designed for slow release by incorporating the herbicide in positively charged vesicles of didodecyldimethylammonium (DDAB), which were adsorbed on the negatively charged clay, montmorillonite. Freeze fracture...

Clay minerals are layer type aluminosilicates that figure in terrestrial biogeochemical cycles, in the buffering capacity of the oceans, and in the containment of toxic waste materials. They are also used as lubricants in petroleum extraction and as industrial catalysts for the synthesis of many organic compounds. These applications derive fundamentally from the colloidal size and permanent str...

A pattern-based approach to the presentation, codi cation and reuse of property speci cations for nite-state veri cation was proposed by Dwyer and his colleagues in [4,3]. The patterns enable nonexperts to read and write formal speci cations for realistic systems and facilitate easy conversion of speci cations between formalisms, such as LTL, CTL, QRE. In this paper we extend the pattern system...

It is known that Dodgson’s rule is computationally very demanding. Tideman (1987) suggested an approximation to it but did not investigate how often his approximation selects the Dodgson winner. We show that under the Impartial Culture assumption the probability that the Tideman winner is the Dodgson winner tend to 1. However we show that the convergence of this probability to 1 is slow. We sug...

Two people have a full B-gallon jug of wine and two empty jugs of capacity M and S, respectively, where B= M +S. Any jug may be poured into any other jug until either the first one is empty or the second is full. What is the quickest way for them to divide the wine equally? We solve this problem and show that a natural related problem may be solved in polynomial time.

In many environments a large portion of particulate material is contained in aggregated particles; however, there is no validated framework to describe how aggregates in the ocean scatter light. Here we present the results of two experiments aiming to expose the role that aggregation plays in determining particle light scattering properties, especially in sediment-dominated coastal waters. Firs...