Figure 1 XRD patterns of several samples: (a) O, O-di-n-cetyldithiophosphate and surface-modified Cu products with molar ratios of P to Cu of (b) 1 2; (c) 1 5; and (d) 1 10.
These high values could be an effect of treatments with different Cu products made during the time [9,26], and also as a pollution effect from the two metallurgical factories in Baia-Mare, Romplumb and Cuprom (57 km from Turulung area) which are the main sources of pollution for the city [12] and also for the neighboring agricultural areas.
The soluble Cu oxidation product was determined to be Cu II) by a mass/charge balance.
In the active state, the cathodic dissolution of copper through an intermediate reaction product, Cu hydride, seems to occur simultaneously with the anodic dissolution of titanium; the dissolution of copper from the alloys is immediately followed by copper redeposition.
During the formation process, a blue fresh product Cu(OH 2 is formed immediately after the addition of OH−, which turns into brown color of copper oxide after a few minutes of sonication.
With increase in the solution concentration up to 10 mg/L the concentrations product Cu(OH 2 will exceed the dissociation constant; consequently the deposited amorphous particles of copper hydroxides can adhere to the cell surface leading to membrane permeability deterioration thus disrupting the cell life functions.
Quick off the mark, the Consumers Union (CU), an independent product-testing laboratory in Yonkers, New York, has also bought some of the new sets to put through their paces.
Figure 4 UV-vis spectra of as-obtained Cu 2 O products with different reaction time.
Figure 6 Photodegradation of MO in an aqueous solution with Cu 2 O products and different amount of H 2 O 2. (a) 4 h (S1), (b) 6 h (S2), (c) 8 h (S3), and (d) 10 h (S4).
Figure 7 Photocatalytic activity of as-obtained Cu 2 O products with different amount of H 2 O 2. Plots of concentration ratio of MO in an aqueous solution against given irradiation intervals in the presence of Cu2O products with different amount of H2O2: (a) 40 μL, (b) 100 μL, and (c) 1,000 μL.
