The purpose of this paper was to investigate the possibility of treating C. I. Reactive Blue 19 wastewater by electrochemical oxidation via electrogenerated active chlorine, using metallic oxide coatings （dimensional...The purpose of this paper was to investigate the possibility of treating C. I. Reactive Blue 19 wastewater by electrochemical oxidation via electrogenerated active chlorine, using metallic oxide coatings （dimensional stable anode, DSA） as anode. The electrolysis for the simulated wastewater was conducted at a constant current. Absorbances at 592 nm and 255 nm were measured to follow the decolorization of the dye and the degradatin of its aromatic ring. After 4 h of electrolysis under the experimental conditions： current density of 15 A·m^-2, 0.2 mol·L^-1 NaCl, 0.1 mol·L^-1 Na2SO4, 0.1 mmol·L^-1 dye, initial pH=6.4 and T=30℃, 100% decolorization of the dye and about 45% degradation of its aromatic ring were achieved, while no obvious change of total organic carbon was observed. The experimental results suggest that the decolorization of the dye and degradation of its aromatic ring were directly affected by current density, temperature, concentrations of the dye and sodium chloride, while slightly affected by initial pH and sodium sulfate concentration; the decolorization of the dye and degradation of its aromatic ring followed pseudo-first-order kinetics; and indirect electrooxidation, using electrogenerated active chlorine, predominated in the electrochemical oxidation.展开更多
The effects of L-cysteine concentration on biohydrogen production by Enterobacterium Bacterium M580 were investigated in batch cultivation.The experimental results showed that L-cysteine could enhance the cell growth,...The effects of L-cysteine concentration on biohydrogen production by Enterobacterium Bacterium M580 were investigated in batch cultivation.The experimental results showed that L-cysteine could enhance the cell growth,hydrogen production rate and hydrogen yield when its concentration was less than 500 mg·L-1,while it had negative effects when its concentration was higher than 500 mg·L-1.The hydrogen production was the highest 1.29 mol·mol-1(H2/glucose) when 300 mg·L-1L-cysteine was added into the culture,and the yield was 9.4% higher than that in the control.The oxidation-reduction potential(ORP) ,which was influenced by L-cysteine,also affected hydrogen production.The ORP values were in the range-300 mV to-150 mV when the L-cysteine concentration was higher than 500 mg·L-1.Although the ORP in this range was favorable for hydrogen production,it was not suitable for the biomass growth.Hence,less hydrogen was produced.When the L-cysteine concentration was lower than 500 mg·L-1,the ORP was more suitable for both biomass growth and hydrogen production.In addition,at least 91%glucose was consumed when L-cysteine was added to the culture media,compared to the 97.37% consumption without L-cysteine added.展开更多
For the ever-growing demand of advanced lithium-ion batteries, it is highly desirable to grow self-supported micro-/nanostructured arrays on metal substrates as electrodes directly. The in-situ growth of electrode mat...For the ever-growing demand of advanced lithium-ion batteries, it is highly desirable to grow self-supported micro-/nanostructured arrays on metal substrates as electrodes directly. The in-situ growth of electrode materials on the conducting substrates greatly simplifies the electrode fabrication process without using any binders or conductive additives. Moreover, the well-ordered arrays closely connected to the current collectors can provide direct electron transport pathways and enhanced accommodation of strains arisen from lithium ion lithiation/delithiation. This article summarizes our recent work on design and construction of lithium-ion battery electrodes on metal substrates. An aqueous solution-based process and a microemulsion-mediated process have been respectively presented to control the kinetic and thermodynamic processes for the micro-/nanostructured array growth on metal substrates, with particular attention to CuO nanorod arrays and microcog arrays successfully prepared on Cu foil substrates. They can be directly used as binder-free electrodes to build advanced lithium-ion batteries with high energy, high safety and high stability.展开更多
This paper elaborated on the sustainability of the copper extraction process. In fact, an alternative copper extraction route from mixed sulphide ores, chalcopyrite and chalcocite using mesophilic biomass consortium a...This paper elaborated on the sustainability of the copper extraction process. In fact, an alternative copper extraction route from mixed sulphide ores, chalcopyrite and chalcocite using mesophilic biomass consortium at 33.3 °C and ferric leaching process were attempted. Bioleaching experiments were settled with a fraction size of-75+53 μm. Bacteria were used as the catalyst. A copper yield of 65.50% was obtained. On the other hand, in ferric leaching process, with a fraction size of-53+38 μm, when the temperature was increased to 70 °C, the copper leaching rate increased to 78.52%. Thus, comparatively, the mesophilic bioleaching process showed a more obvious advantage in copper extraction than leaching process with a high temperature. However, it has been resolved from the characterization performed using SEM-EDS, FTIR and XRD observations coupled with different thermodynamic approaches that, the indirect mechanism is the main leaching mechanism, with three transitory mechanisms(polysulphide, thiosulphate and elemental sulphur mechanisms) for the mixed chalcopyrite-chalcocite ore. Meanwhile, the speciation turns into Cu2 S-Cu S-Cu5 Fe S4-Cu2 S before turning into Cu SO4. While ferrous oxidation and the formation of ferric sulphate occur, and there is a formation of strong acid as bacteria digest sulphide minerals into copper sulphate at low temperature, which is why this copper production scenario requires a redox potential more than 550 m V at room temperature for high copper leaching rate.展开更多
Tocopherol is the most active vitamin and natural antioxidant existing in the nature known as vitamin E. Lacking of this vitamin makes drastic exchanges on the health of the living organisms. Their active chemical for...Tocopherol is the most active vitamin and natural antioxidant existing in the nature known as vitamin E. Lacking of this vitamin makes drastic exchanges on the health of the living organisms. Their active chemical form is l-α-tocopherol substance. In this article, α-thiotocopherol a tocopherol derivative was synthesized via a precursor like dl-α-tocopherol, which has better antioxidant than natural α-tocopherol. And the last compound after separation and purification via TLC and PC procedures was analyzed by FTIR, GC-MS and elemental analysis, oxidative stability is tested with TGA method in air showing roughly antioxidant effect. Another approach is measurment of redox potential against a reference electrode under inert nitrogen atmosphere.展开更多
Controlling the biogas fermentation process is the key for maintaining stable operation of biogas system and increasing gas yield. Aiming at features of biogas fermentation process and difficulties of control, a pract...Controlling the biogas fermentation process is the key for maintaining stable operation of biogas system and increasing gas yield. Aiming at features of biogas fermentation process and difficulties of control, a practical control scheme is proposed combining the abundant experience of biogas experts. And it discussed the structural design and hardware configuration of the expert control system, established the database and role base, and designed the control strategy of production system inference. The design scheme with ZigBee and PDA technology as core is employed so as to solve problems of environmental factor detection and data transfer management. The test result shows that the deviation of temperature is controlled within ± 0.9℃, the deviation of pH is controlled within ±0.3, the deviation of oxidation-reduction potential is controlled within ±30mV, the deviation of gas production is controlled within ± 9mL and that of methane concentration is controlled within ±4.5%. This system is easily expandable and applicable to biogas engineering at various scales.展开更多
文摘The purpose of this paper was to investigate the possibility of treating C. I. Reactive Blue 19 wastewater by electrochemical oxidation via electrogenerated active chlorine, using metallic oxide coatings （dimensional stable anode, DSA） as anode. The electrolysis for the simulated wastewater was conducted at a constant current. Absorbances at 592 nm and 255 nm were measured to follow the decolorization of the dye and the degradatin of its aromatic ring. After 4 h of electrolysis under the experimental conditions： current density of 15 A·m^-2, 0.2 mol·L^-1 NaCl, 0.1 mol·L^-1 Na2SO4, 0.1 mmol·L^-1 dye, initial pH=6.4 and T=30℃, 100% decolorization of the dye and about 45% degradation of its aromatic ring were achieved, while no obvious change of total organic carbon was observed. The experimental results suggest that the decolorization of the dye and degradation of its aromatic ring were directly affected by current density, temperature, concentrations of the dye and sodium chloride, while slightly affected by initial pH and sodium sulfate concentration; the decolorization of the dye and degradation of its aromatic ring followed pseudo-first-order kinetics; and indirect electrooxidation, using electrogenerated active chlorine, predominated in the electrochemical oxidation.
基金Supported by the National High Technology Research and Development Program of China（2006AA02Z246 2007AA03Z456） the National Natural Science Foundation of China（20776119）+2 种基金 the Specialized Research Fund for the Doctoral Program of Higher Education of China（20096101120023） Shaanxi Provincial Natural Science Foundation（SJ08B03） Shaanxi Key Subject Program China
文摘The effects of L-cysteine concentration on biohydrogen production by Enterobacterium Bacterium M580 were investigated in batch cultivation.The experimental results showed that L-cysteine could enhance the cell growth,hydrogen production rate and hydrogen yield when its concentration was less than 500 mg·L-1,while it had negative effects when its concentration was higher than 500 mg·L-1.The hydrogen production was the highest 1.29 mol·mol-1(H2/glucose) when 300 mg·L-1L-cysteine was added into the culture,and the yield was 9.4% higher than that in the control.The oxidation-reduction potential(ORP) ,which was influenced by L-cysteine,also affected hydrogen production.The ORP values were in the range-300 mV to-150 mV when the L-cysteine concentration was higher than 500 mg·L-1.Although the ORP in this range was favorable for hydrogen production,it was not suitable for the biomass growth.Hence,less hydrogen was produced.When the L-cysteine concentration was lower than 500 mg·L-1,the ORP was more suitable for both biomass growth and hydrogen production.In addition,at least 91%glucose was consumed when L-cysteine was added to the culture media,compared to the 97.37% consumption without L-cysteine added.
基金Supported by the National Natural Science Foundation of China(NSFC Grants21176054 and 21271058)
文摘For the ever-growing demand of advanced lithium-ion batteries, it is highly desirable to grow self-supported micro-/nanostructured arrays on metal substrates as electrodes directly. The in-situ growth of electrode materials on the conducting substrates greatly simplifies the electrode fabrication process without using any binders or conductive additives. Moreover, the well-ordered arrays closely connected to the current collectors can provide direct electron transport pathways and enhanced accommodation of strains arisen from lithium ion lithiation/delithiation. This article summarizes our recent work on design and construction of lithium-ion battery electrodes on metal substrates. An aqueous solution-based process and a microemulsion-mediated process have been respectively presented to control the kinetic and thermodynamic processes for the micro-/nanostructured array growth on metal substrates, with particular attention to CuO nanorod arrays and microcog arrays successfully prepared on Cu foil substrates. They can be directly used as binder-free electrodes to build advanced lithium-ion batteries with high energy, high safety and high stability.
文摘This paper elaborated on the sustainability of the copper extraction process. In fact, an alternative copper extraction route from mixed sulphide ores, chalcopyrite and chalcocite using mesophilic biomass consortium at 33.3 °C and ferric leaching process were attempted. Bioleaching experiments were settled with a fraction size of-75+53 μm. Bacteria were used as the catalyst. A copper yield of 65.50% was obtained. On the other hand, in ferric leaching process, with a fraction size of-53+38 μm, when the temperature was increased to 70 °C, the copper leaching rate increased to 78.52%. Thus, comparatively, the mesophilic bioleaching process showed a more obvious advantage in copper extraction than leaching process with a high temperature. However, it has been resolved from the characterization performed using SEM-EDS, FTIR and XRD observations coupled with different thermodynamic approaches that, the indirect mechanism is the main leaching mechanism, with three transitory mechanisms(polysulphide, thiosulphate and elemental sulphur mechanisms) for the mixed chalcopyrite-chalcocite ore. Meanwhile, the speciation turns into Cu2 S-Cu S-Cu5 Fe S4-Cu2 S before turning into Cu SO4. While ferrous oxidation and the formation of ferric sulphate occur, and there is a formation of strong acid as bacteria digest sulphide minerals into copper sulphate at low temperature, which is why this copper production scenario requires a redox potential more than 550 m V at room temperature for high copper leaching rate.
文摘Tocopherol is the most active vitamin and natural antioxidant existing in the nature known as vitamin E. Lacking of this vitamin makes drastic exchanges on the health of the living organisms. Their active chemical form is l-α-tocopherol substance. In this article, α-thiotocopherol a tocopherol derivative was synthesized via a precursor like dl-α-tocopherol, which has better antioxidant than natural α-tocopherol. And the last compound after separation and purification via TLC and PC procedures was analyzed by FTIR, GC-MS and elemental analysis, oxidative stability is tested with TGA method in air showing roughly antioxidant effect. Another approach is measurment of redox potential against a reference electrode under inert nitrogen atmosphere.
文摘Controlling the biogas fermentation process is the key for maintaining stable operation of biogas system and increasing gas yield. Aiming at features of biogas fermentation process and difficulties of control, a practical control scheme is proposed combining the abundant experience of biogas experts. And it discussed the structural design and hardware configuration of the expert control system, established the database and role base, and designed the control strategy of production system inference. The design scheme with ZigBee and PDA technology as core is employed so as to solve problems of environmental factor detection and data transfer management. The test result shows that the deviation of temperature is controlled within ± 0.9℃, the deviation of pH is controlled within ±0.3, the deviation of oxidation-reduction potential is controlled within ±30mV, the deviation of gas production is controlled within ± 9mL and that of methane concentration is controlled within ±4.5%. This system is easily expandable and applicable to biogas engineering at various scales.
