The addition of inexpensive montmorillonite clay to a silicone resin employed as preceramic polymer was found to be advantageous for the production of SiOC glass matrix composites. Dense SiOC based monoliths were achieved with the addition of a substantial amount of calcined clay (30 wt.%) to the preceramic polymer; these composites exhibited remarkable hardness and fracture toughness, higher t...

The hypothesis presented in this article serves a twofold function: (a) a means of predicting whether an aminofluorene is carcinogenic or not and (6) an indication of a possible site in the aminofluorene molecule which is capable of com bining with some cell substance. This study deals with the chemical reactivity of an extensive num ber of aminofluorenes and aminofluorenones and involves their...

AIM A standard procedure does not exist to distinguish between attached and unattached micro-organisms. In this study, we compared two methods to quantify between Escherichia coli attached to clay particles and E. coli freely suspended in solution: flow cytometry (attachment assay and viability assay) and settling (or centrifugation followed by settling). METHODS AND RESULTS Methods were test...

Acid–base chemistry of clay minerals is central to their interfacial properties, but up to now a quantitative understanding on the surface acidity is still lacking. In this study, with first principles molecular dynamics (FPMD) based vertical energy gap technique, we calculate the acidity constants of surface groups on (010)-type edges of montmorillonite and kaolinite, which are representatives...

A magnesium hydroxide-montmorillonite complex prepared at an OH/Mg molar ratio of 2 (16 meq Mg/g clay) and immediately cleaned of any free Mg(OH)2 behaves like magnesium-chlorite and shows no change during 3 months ageing. Magnesium hydroxide completely precipitates within the interlayer space of montmorillonite. X-ray diffraction analysis, thermal (DTA and TGA) studies, i.r. absorption analysi...

Maleic anhydride-modified polypropylene was compounded with commercially available surface-modified montmorillonite in a twin-screw extruder. Recompounding ensured the removal of visible tactoids from the extrudate but TEM and XRD techniques showed nonuniform dispersion of clay platelets. In this study, we investigated the mechanical and fracture properties of nanoclayfilled polypropylene. Emph...

The use of organo-clays in wastewater treatment, as alternatives to activated C for sorbing pollutants, and in clay liners is of great interest to soil and environmental scientists. There is a lack of information, however, on the kinetics and mechanisms of organo-clay interactions with pollutants. Accordingly, in this study, the time-dependent adsorption and desorption of phenol and aniline on ...

The present study was carried out on the effect of acid leaching on the modification and structure alteration of montmorillonite. A nanostructured, activated material was prepared by selective leaching of pure smectite clay with different concentrations of sulfuric acid (1 10 N/L) at 85 ̊C for 120 min using a solid/liquid ratio of 1:20 and a reflux system. The Fourier transform infrared (FTIR), ...

This paper examines the effect of surface treatment and filler shape factor on the fracture toughness and elastic modulus of epoxy-based nanocomposite. Two forms of nanofillers, polydopamine-coated montmorillonite clay (D-clay) and polydopamine-coated carbon nanofibres (D-CNF) were investigated. It was found that Young's modulus increases with increasing D-clay and D-CNF loading. However, the f...

Sorption of molecular amines by montmorillonite involves protonation of the amine group and hydrolysis of the interlayer cation. Sorption and subsequent desorption of amines may render some of the interlayer cations non-exchangeable, thus causing partial 'chloritization' of the montmorillonite. The effect is stronger with interlayer A1 than Ca ions and depends upon the amine sorbed. I N T R O D...