We studied effects of free copper ion activity and total copper concentration on copper uptake by lettuce from nutrient solution and a model was developed. In ethylenediaminetetraacetic acid and dissolved organic matter treatments, when pH and free copper ion activity were the same, root copper concentration did not change with the total copper concentration. However, at fixed pH and total copp...

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...

The present study investigates an NF process for removal of copper and hexavalent chromium, studying the effect of pH (5, 7, 9) as well as contaminants' concentration (50, 500, 5000 µg/L) at a constant pressure of 8 bar; with the recovery rate, regulated at 75±2%. To determine the main factors, affecting the system performance, and evaluate the interaction effects among the factors, the experim...

Copper (Cu) and mercury (Hg) enter aquatic ecosystems from different sources threatening health of aquatic organisms such as fish. As such, in this investigation, determinaing, Cu and Hg toxic concentration in Caspian roach (Rutilus rutilus caspicus), was undertaken. Acute toxicity of Cu and Hg were determined in fish specimen under semi-static condition. Caspian roach fry (~ 1 g) were exp...

A multigeneration acclimation experiment was performed with Daphnia magna exposed to copper to assess possible changes in tolerance and to establish the optimal concentration range (OCEE) of this species. The hypothesis was tested that as the bioavailable background concentration of an essential metal increases (within realistic limits), the natural tolerance (to the metal) of the acclimated/ad...

Twenty-eight Brangus cattle were used to determine the effect of copper and selenium supplementation on performance, feed efficiency, composition of fatty acids in Longissimus dorsi (LD) muscle, and cholesterol concentration in serum and in LD muscle and enzymes activities, reduced glutathione (GSH) and oxidized glutathione (GSSG). The treatments were: i) Control, without copper (Cu) and seleni...

background: the pollution of the aquatic environment with heavy metals has become a worldwide problem during recent years, due to their potential toxic effects and ability to bio-accumulate in aquatic ecosystems. heavy metals are sensitive indicators for monitoring changes in the aquatic environment. methods: in this study, total concentrations of cr, pb, cu, zn, and fe were measured in water a...

a simple and sensitive extraction-fluorimetric method for the determination of copper is reported. the 1,7-diaza-15-crown-5-copper-rose bengal (da15c5-cu-rb) ternary complex is quantitatively extracted into chloroform, diluted with ammoniacal acetone and its fluorescence intensity is measured at 570 nm with excitation at 540 nm. a linear calibration graph was obtained over the copper concentrat...