the main goal of this study is to investigate the capability of zeolites a and p synthesized from iranian natural clinoptilolite for uranium uptak. the removal of uranium(vi) from aqueous solution via ion exchange by zeolites in a single component system with various contact times,  temperatures and initial concentrations of uranium(vi) was investigated. the experimental results were fitted to ...

A novel amperometric biosensor for the determination of Al(III) based on the inhibition of the enzyme acetylcholinesterase has been developed. The immobilization of the enzyme was performed on screen-printed carbon electrodes modified with gold nanoparticles. The oxidation signal of acetylthiocholine iodide enzyme substrate was affected by the presence of Al(III) ions leading to a decrease in t...

A organic-solution-processable functionalized-graphene (SPFGraphene) material has been studied on pre-concentration and determination of trace Mo(II)ions. In this process, the effects of pH solution, elution conditions on pre-concentration of trace Mo(II) were studied and the effect of interfering ions was also investigated. A selective method for the fast determination of trace amounts of Mo (...

bioleaching processes for extraction of cu and mo from molybdenite cons. are more environmentally friendly and consume less energy than conventional technologies, yet less economically efficient. one necessary step towards arriving at a cost-effective bioleaching process is using appropriate methodology to optimize pertinent factors in such processes. to this end, the present study employed res...

This study evaluates the effects of different additives such as silver ion, medium and energy sources on the efficiency of mixed moderate thermophilic bioleaching approach to extract Cu, Mo and Re from molybdenite concentrate containing 0.98% Cu, 1.56% Fe, 53.84% Mo, and 0.055% Re. Molybdenite was the major phase of Mo-bearing mineral and chalcopyrite, covellite and pyrite were distinguished as...

The transition element molybdenum (Mo) possesses diverse valances (+II to +VI), and is involved in forming cofactors in more than 60 enzymes in biology. Redox switching of the element in these enzymes catalyzes a series of metabolic reactions in both prokaryotes and eukaryotes, and the element therefore plays a fundamental role in the global carbon, nitrogen, and sulfur cycling. In the present ...

Chromium can act either as an essential micronutrient or a chemical carcinogen, depending on its oxidation state. Of the two most stable chromium oxidation states, Cr(VI) is a known carcinogen, while Cr(III) is an essential element. Determination of total Cr cannot therefore be used to evaluate food safety of dairy products, as speciation is required for accurate assessment of potential toxicit...