background: there are great resources of natural zeolite in iran. zeolite, an inorganic ion-exchanger, may be used as a suitable technical-economical solution for water treatment in many regions of iran. in this study, the characterization of natural zeolite natrolite and the feasibility of removing hardness, cations, and anions were investigated. methods: first, zeolite composition and type we...

the complexive abilities of 5,11,17-tddert-butyl-23 amino-25.26,27,28-tet3propoxy-calix[4]arere and5,1127-tri-amino-23 acelyktert-butylamide-25,26,27,28-tetrabutoxy-calixplarene towards alkali metalions lit nat, kt ric and cs+ in methanol-chloroform mixture have been evaluated at 25 °c, using uvvis spectrophotometric techniques. the results showed that the hgands are capable to complex with all...

Steel pipelines are susceptible to corrosion by the action of corrosive substance in the environment and one of the most common failure modes in buried pipeline coatingis cathodic disbondment. Consequently, Electrochemical Impedance Spectroscopy (EIS) was used to assess the effect of three important parameters, the thickness of coating, the artificial defect ...

steel pipelines are susceptible to corrosion by the action of corrosive substance in the environment and one of the most common failure modes in buried pipeline coatingis cathodic disbondment. consequently, electrochemical impedance spectroscopy (eis) was used to assess the effect of three important parameters, the thickness of coating, the artificial defect and electrolyte type, on cathodic di...

Four new manganese(II) complexes, based on dinitro and tetranitrothiacalix[4]arenes, were synthesized characterized from structural points of view in the crystalline phase. It was revealed that thiacalix[4]arenes decorated with two four electron withdrawing groups, when combined MnCl2, afforded formation similar tetranuclear complexes 1 2a non-equivalent metal ions a rhombic geometry metallic c...

The factors influencing the oligomerization state of OXA-10 and OXA-14 class D beta-lactamases in solution have been investigated. Both enzymes were found to exist as an equilibrium mixture of a monomer and dimer, with a K(d) close to 40 microM. The dimeric form was stabilized by divalent metal cations. The ability of different metal ions to stabilize the dimer was in the following order: Cd(2+...

We describe a series of molecular dynamics simulations performed on model cation-water systems at 25 “C representing the behavior of Li+, Na+, K+, Rbf, and Cs+ in an electric field of 1.0 V/nm and in its absence. The TIP4P model was used for water and TIPS potentials were adapted for the ion-water interactions. The structure of the surrounding water molecules around the cations was found to be ...