This work deals with geopolymers based on local Jordanian resources, namely, kaolin and zeoltitic (phillipsite) tuff. The geopolymers were prepared from these two materials by a reaction with an alkali solution at 80oC. The research group of the present work has demonstrated in previous work that addition of zeolitic tuff to kaolin based-geopolymers increases the adsorption capacity toward Cu(I...

BACKGROUND Metal ions participate in the three-dimensional folding of RNA and provide active centers in catalytic RNA molecules. The positions of metal ions are known for a few RNA structures determined by X-ray crystallography. In addition to the crystallographically identified sites, solution studies point to many more metal ion binding sites around structured RNAs. Metal ions are also presen...

Mercury ion (Hg2+) is recognized as one of the most toxic metal ions for the environment and for human health. Techniques utilized in the detection of Hg2+ are an important factor. Herein, a simple thymine was successfully employed as the surface enhanced Raman spectroscopy sensor for Hg2+ ion detection. The limit of detection (LOD) of the developed sensor is better than 0.1 nM (0.02 ppb). This...

The folding and catalytic function of RNA molecules depend on their interactions with divalent metal ions, such as magnesium. As with every molecular process, the most basic knowledge required for understanding the close relationship of an RNA with its metal ions is the stoichiometry of the interaction. Unfortunately, inventories of the numbers of divalent ions associated with unfolded and fold...

direct orthogonal signal correction(dosc) and savitzky-golay filters (sgf) were applied as preprocessing methods on the original and first derivative absorbance data. principle component regression (pcr), partial least squares (pls) and iterative target transformation factor analysis (ittfa), were used in spectrophotometric simultaneous determination of heavy divalent metal ions, lead, zinc,mer...

the interaction between some heavy metal ions such as of pb(ii), cd(ii) and cu(ii) ions from aqueous solution adsorbed by single walled carbon nanotube (swcnts) and carboxylate group functionalized single walled carbon nanotube (swcnt-cooh) surfaces were studied by atomic absorption spectroscopy. the effect of contact time, ph, initial concentration of ion, ionic strength and temperature on the...

oxime extractants 3-tert-butyl-2-hydroxy-5-methyl benzaldehyde oxime (hl1) and 3-tert-butyl-2-hydroxy-5-methoxy benzaldehyde oxime (hl2) were synthesized and characterized by conventional spectroscopic methods. suitable lipophilic nature of the prepared extractants allowed examining the ability of these molecules for extraction-separation of copper from its mixture with normally associated meta...

-Biofilm is communities of microorganisms attached to the surface and is able to concentrate metal species within their cell structure. Therefore, the aim of this study was to produce Escherichia coli biofilm on zeolite (clinoptilolite) and evaluate its ability for nickel (Ni) and chromium (Cr) adsorption from aqueous solutions. A laboratory-scale batch model was used for biodsorption assay. Th...

This paper deals with adsorption of Pb and Hg on the exopolysaccharide produced by Azotobacter chroococcum XU1. The adsorption of metal ions was significantly affected by the pH of metal solutions (Pb(NO3)2 and Hg(NO3)2), metal ions concentration and exopolysaccharide concentrations. At optimum pH the uptakes of the metals were 40.48% and 47.87% respectively. The metal ions biosorption was high...