Modified clays were used to remove ethyl acetate from aqueous solutions. These clays were regenerated using supercritical CO2. Structural changes in the montmorillonite clay after treatment with quaternary amines were studied. The surface properties of the modified clay changed from highly hydrophilic to highly organophilic. The clay was regenerated by percolation of a stream of CO2 through the...

The interactions of clay minerals with organic compounds which give rise to the formation of colored complexes, are discussed. The color reactions of clays can be ascribed to a charge transfer between the mineral and the adsorbed species. The active sites on the clay are aluminums exposed at crystal edges and/or transition metal cations in the higher valency state at planar surfaces both of whi...

Heterogeneous catalysis and their application in industrial-scale organic synthesis of fine chemicals are greatly facilitated by catalysis and further on by catalyst recovery and recycles to fits most “principles of green chemistry. In acid media, terpenoids generally undergoes various transformations. The terpenoid transformations include various liquid Bronsted and Lewis Acids, Acid clays, He...

fibrous dysplasia of the bone (fdb) is a common, genetic, developmental disorder with a benign course. fdb can be seen anywhere throughout the skeleton. it is usually asymptomatic and found incidentally on imaging studies that are performed for other purposes. although whole body 18 f-flourodeoxyglucose pet/ct (fdg pet/ct) is widely used in tumor imaging, infections and benign pathologies like ...

herein, we report the f-18 fluorodeoxyglucose (18f-fdg) positron emission tomography (pet)/computed tomography (ct) findings of a benign solitary fibrous tumor (sft) of the kidney. the patient was a 63-year-old woman with a mass in the right kidney (10×9.7 cm), incidentally found on ct images. the ct scan showed a lobulated tumor arising from the hilum of the right kidney. the tumor consisted o...

Compacted clay has traditionally been used as a lining material in municipal solid waste landfills. However, natural clays may not always provide good contaminant sorption properties. One alternative material that is abundant in some parts of Europe and Turkey as well as Western United States is sepiolite. A laboratory study was undertaken to investigate the feasibility of sepiolite as a liner ...

[1] To understand the aqueous history of Mars, it is critical to constrain the alteration mineralogy of the Martian surface. Previously published analyses of thermal infrared (l = 6–25 mm) remote sensing data of Mars suggest that dark regions have 15–20% clay minerals. However, near-infrared (l = 1–3 mm) spectral results generally do not identify widespread clay minerals. Thermal infrared detec...

liquid crystal, colloid, SAXS Suspensions of three different clays in K15, a thermotropic liquid crystal have been studied by optical microscopy and small angle X-ray scattering. The three clays were Claytone AF, a surface treated natural montmorillonite, Laponite RD, a synthetic hectorite and mined Sepiolite. The Claytone and Laponite were sterically stabilized whereas Sepiolite formed a relat...

a 29- year old female with bone pain and history of precocious puberty was referred for bone scintigraphy. on physical examination café au lait macular spots were noted on her neck, buttocks and left leg. bone scan showed multiple areas of intense increased activity which was in favour of polyostotic fibrous dysplasia. considering the presence of polyostotic fibrous dysplasia, precocious pubert...

A simple formalism is presented to model the behaviour of expansive clays. Two levels of structure are considered. The behaviour of the macrostructure follows the model developed for unsaturated materials by Alonso et al. [Géotechnique 40 (3) (1990) 405–430]. The behaviour of the microstructure is adapted from the work of Gens and Alonso [Can. Geotech. J. 29 (1992) 1013–1032] in order to includ...