Misreported pyrite into copper concentrates dramatically declines copper grade and recovery. Copper flotation can be also more complicated if flotation feed comes from an elevated-pyritic copper ore. In this investiga...Misreported pyrite into copper concentrates dramatically declines copper grade and recovery. Copper flotation can be also more complicated if flotation feed comes from an elevated-pyritic copper ore. In this investigation, the effect of two different ore types(high pyritic and low pyritic feeds) was studied on rougher stage of industrial copper flotation circuit. Samples were taken from different streams and the structure of chalcopyrite within the pyrite and non-sulfide gangue minerals was examined in various size fractions for mentioned ore types. Results indicated that 72% and 56% of the total floated pyrite was transferred to concentrate in first four cells in the low and high pyritic feeds, respectively. Whereas, this proportion for floated SiO_2 in last ten cells was detected as 72% and 71%, respectively. A detailed interpretation of the effect of locked particles in different size fractions on rougher flotation cells is studied from industrial point of view.展开更多
Low toxic graphene quantum dot(GQD) was synthesized by pyrolyzing citric acid in alkaline solution and characterized by ultraviolet-visible(UV-vis) spectroscopy,X-ray diffraction(XRD),atomic force microscopy(AF...Low toxic graphene quantum dot(GQD) was synthesized by pyrolyzing citric acid in alkaline solution and characterized by ultraviolet-visible(UV-vis) spectroscopy,X-ray diffraction(XRD),atomic force microscopy(AFM),spectrofluorimetery and dynamic light scattering(DLS) techniques.GQD was used for electrode modification and electro-oxidation of doxorubicin(DOX) at low potential.A substantial decrease in the overvoltage(- 0.56 V) of the DOX oxidation reaction(compared to ordinary electrodes) was observed using GQD as coating of glassy carbon electrode(GCE).Differential pulse voltammetry was used to evaluate the analytical performance of DOX in the presence of phosphate buffer solution(pH 4.0) and good limit of detection was obtained by the proposed sensor.Such ability of GQD to promote the DOX electron-transfer reaction suggests great promise for its application as an electrochemical sensor.展开更多
A simple and rapid protocol for the synthesis of polystyrene-graphene oxide nanocomposite (PS/GONC) was achieved for first time using an in situ polymerization method. PS/GONC modified glassy carbon electrode (PS/G...A simple and rapid protocol for the synthesis of polystyrene-graphene oxide nanocomposite (PS/GONC) was achieved for first time using an in situ polymerization method. PS/GONC modified glassy carbon electrode (PS/GONC/GCE) has been employed as an efficient nanosensor for the electrooxidation of histamine. The PS/GONC/GCE is used as an electrochemical nanosensors for monitoring histamine using differential pulse voltammetry techniques (detection limit 0.03 μmol/L). In addition, the prepared nanosensor was successfully applied to determine histamine in fish samples, yielding satisfactory results. The spiked recoveries were in the range of 98.2%-103.1%.展开更多
基金the financial support of National Iranian Copper Industries Company (N.I.C.I.Co.)
文摘Misreported pyrite into copper concentrates dramatically declines copper grade and recovery. Copper flotation can be also more complicated if flotation feed comes from an elevated-pyritic copper ore. In this investigation, the effect of two different ore types(high pyritic and low pyritic feeds) was studied on rougher stage of industrial copper flotation circuit. Samples were taken from different streams and the structure of chalcopyrite within the pyrite and non-sulfide gangue minerals was examined in various size fractions for mentioned ore types. Results indicated that 72% and 56% of the total floated pyrite was transferred to concentrate in first four cells in the low and high pyritic feeds, respectively. Whereas, this proportion for floated SiO_2 in last ten cells was detected as 72% and 71%, respectively. A detailed interpretation of the effect of locked particles in different size fractions on rougher flotation cells is studied from industrial point of view.
基金financial support by the Hematology-Oncology Research Center,Tabriz University of Medical Sciences,under Grants No.93/5
文摘Low toxic graphene quantum dot(GQD) was synthesized by pyrolyzing citric acid in alkaline solution and characterized by ultraviolet-visible(UV-vis) spectroscopy,X-ray diffraction(XRD),atomic force microscopy(AFM),spectrofluorimetery and dynamic light scattering(DLS) techniques.GQD was used for electrode modification and electro-oxidation of doxorubicin(DOX) at low potential.A substantial decrease in the overvoltage(- 0.56 V) of the DOX oxidation reaction(compared to ordinary electrodes) was observed using GQD as coating of glassy carbon electrode(GCE).Differential pulse voltammetry was used to evaluate the analytical performance of DOX in the presence of phosphate buffer solution(pH 4.0) and good limit of detection was obtained by the proposed sensor.Such ability of GQD to promote the DOX electron-transfer reaction suggests great promise for its application as an electrochemical sensor.
基金the support of this work by Drug Applied Research Center,Tabriz University of Medical Science and Payame Noor University
文摘A simple and rapid protocol for the synthesis of polystyrene-graphene oxide nanocomposite (PS/GONC) was achieved for first time using an in situ polymerization method. PS/GONC modified glassy carbon electrode (PS/GONC/GCE) has been employed as an efficient nanosensor for the electrooxidation of histamine. The PS/GONC/GCE is used as an electrochemical nanosensors for monitoring histamine using differential pulse voltammetry techniques (detection limit 0.03 μmol/L). In addition, the prepared nanosensor was successfully applied to determine histamine in fish samples, yielding satisfactory results. The spiked recoveries were in the range of 98.2%-103.1%.