To achieve"waste controlled by waste",a novel wet process using KMnO_(4)/copper converter slag slurry for simultaneously removing SO_(2)and NO_(x)from acid-making tail gas was proposed.Through the solid-liqu...To achieve"waste controlled by waste",a novel wet process using KMnO_(4)/copper converter slag slurry for simultaneously removing SO_(2)and NO_(x)from acid-making tail gas was proposed.Through the solid-liquid separation for copper slag slurry,the liquid-phase part has a critical influence on removing NO_(x)and SO_(2).Also,the leached metal ions played a crucial role in the absorption of SO_(2)and NO_(x).Subsequently,the effects of single/multi-metal ions on NO_(x)removal was investigated.The results showed that the leached metal from copper converter slag(Al^(3+),Cu^((2+),and Mg^((2+))and KMnO_(4)had a synergistic effect on NO_(x)removal,thereby improving the NO_(x)removal efficiency.Whereas Fe^(2+) had an inhibitory effect on the NO_(x)removal owing to the reaction between Fe^(2+) and KMnO_(4),thereby consuming the KMnO_(4).Besides,SO_(2)was converted to SO_(4)^(2-) completely partly due to the liquid catalytic oxidation by metal ions.The XRD and XPS results indicated that the Fe(Ⅱ)species(Fe_(2)SiO_(4),Fe_(3)O_(4))in copper slag can react with H+ions with the generation of Fe^(2+),and further consumed the KMnO_(4),thereby resulting in a decrease in the NO_(x)removal.The characterization of the slags and solutions before and after reaction led us to propose the possible mechanisms.The role of copper slag is as follows:(1)the alkaline substances in copper slag can absorb SO_(2)and NO_(2)by KMnO_(4)oxidation.(2)copper slag may function as a catalyst to accelerate SO_(2)conversion and improve NO_(x)removal by synergistic effect between leached metal ions and KMnO_(4).展开更多
La0.9Sr0.1Ga0.8Mg0.2O3–？ （LSGM） electrolyte materials were synthesized by the solid state reaction method. The conductivity of LSGM materials was detected by four probe method, and it was 0.08 S/cm at 850 oC. Dens...La0.9Sr0.1Ga0.8Mg0.2O3–？ （LSGM） electrolyte materials were synthesized by the solid state reaction method. The conductivity of LSGM materials was detected by four probe method, and it was 0.08 S/cm at 850 oC. Dense and uniform films of LSGM materials were deposited by the magnetic sputtering on substrates of Si and La0.7Sr0.3Cr0.5Mn0.5O3–？ （LSCM）. The experimental results showed that the deposition rates dropped and the average grain sizes of the films enlarged with increase in the substrate temperatures. In the sputtering process, the LSGM film was deposited with preferred growth direction. After annealing, the preferred growth direction disappeared and the film surface became smoother and denser. Through observing the deposition process, deposition mechanism was proposed, which was consistent with a model of island growth.展开更多
This paper applied wavelet analysis to examining change tendency,multi-time scale variations,periodic and abrupt change characteristics of suspended sediment flux(SSF)of the Panlong basin in the Upper Red River,China....This paper applied wavelet analysis to examining change tendency,multi-time scale variations,periodic and abrupt change characteristics of suspended sediment flux(SSF)of the Panlong basin in the Upper Red River,China.The results indicated that the SSF had increased from 1951 to 1997,but declined since 1998.The variations of the SSF had multi-time scale characteristics and the fluctuations varied in different time periods.Three periodic time scales,4,7 and 22 years,were determined.The 22-year periodic time scale,which was the most obvious one among the three time scales,extended through the whole research period,whereas the 4-and 7-year time scales were obvious only in certain time periods.There were 27 times of abrupt changes across the 4-year time scale,16 times across the 7-year time scale and 5 times across the 22-year time scale,respectively.On the basis of social statistical and climate data analysis,we concluded that the human activities were the main reason that led to the changing tendency of the SSF,but the characteristics of the multi-time scale,periodic and abrupt change were mainly influenced by climate variations.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51708266,51968034,21667015,and 41807373)the National Key Research and Development Program of China(Nos.2018YFC0213400 and 2018YFC1900305)。
文摘To achieve"waste controlled by waste",a novel wet process using KMnO_(4)/copper converter slag slurry for simultaneously removing SO_(2)and NO_(x)from acid-making tail gas was proposed.Through the solid-liquid separation for copper slag slurry,the liquid-phase part has a critical influence on removing NO_(x)and SO_(2).Also,the leached metal ions played a crucial role in the absorption of SO_(2)and NO_(x).Subsequently,the effects of single/multi-metal ions on NO_(x)removal was investigated.The results showed that the leached metal from copper converter slag(Al^(3+),Cu^((2+),and Mg^((2+))and KMnO_(4)had a synergistic effect on NO_(x)removal,thereby improving the NO_(x)removal efficiency.Whereas Fe^(2+) had an inhibitory effect on the NO_(x)removal owing to the reaction between Fe^(2+) and KMnO_(4),thereby consuming the KMnO_(4).Besides,SO_(2)was converted to SO_(4)^(2-) completely partly due to the liquid catalytic oxidation by metal ions.The XRD and XPS results indicated that the Fe(Ⅱ)species(Fe_(2)SiO_(4),Fe_(3)O_(4))in copper slag can react with H+ions with the generation of Fe^(2+),and further consumed the KMnO_(4),thereby resulting in a decrease in the NO_(x)removal.The characterization of the slags and solutions before and after reaction led us to propose the possible mechanisms.The role of copper slag is as follows:(1)the alkaline substances in copper slag can absorb SO_(2)and NO_(2)by KMnO_(4)oxidation.(2)copper slag may function as a catalyst to accelerate SO_(2)conversion and improve NO_(x)removal by synergistic effect between leached metal ions and KMnO_(4).
基金supported by Natural Science Foundation of Yunnan Province(2009ZC027M)Innovation Fund of Science and Technology for Students(2012YA027)
文摘La0.9Sr0.1Ga0.8Mg0.2O3–？ （LSGM） electrolyte materials were synthesized by the solid state reaction method. The conductivity of LSGM materials was detected by four probe method, and it was 0.08 S/cm at 850 oC. Dense and uniform films of LSGM materials were deposited by the magnetic sputtering on substrates of Si and La0.7Sr0.3Cr0.5Mn0.5O3–？ （LSCM）. The experimental results showed that the deposition rates dropped and the average grain sizes of the films enlarged with increase in the substrate temperatures. In the sputtering process, the LSGM film was deposited with preferred growth direction. After annealing, the preferred growth direction disappeared and the film surface became smoother and denser. Through observing the deposition process, deposition mechanism was proposed, which was consistent with a model of island growth.
基金Supported by the China 973 Program(Grant No.2003CB415105-6)
文摘This paper applied wavelet analysis to examining change tendency,multi-time scale variations,periodic and abrupt change characteristics of suspended sediment flux(SSF)of the Panlong basin in the Upper Red River,China.The results indicated that the SSF had increased from 1951 to 1997,but declined since 1998.The variations of the SSF had multi-time scale characteristics and the fluctuations varied in different time periods.Three periodic time scales,4,7 and 22 years,were determined.The 22-year periodic time scale,which was the most obvious one among the three time scales,extended through the whole research period,whereas the 4-and 7-year time scales were obvious only in certain time periods.There were 27 times of abrupt changes across the 4-year time scale,16 times across the 7-year time scale and 5 times across the 22-year time scale,respectively.On the basis of social statistical and climate data analysis,we concluded that the human activities were the main reason that led to the changing tendency of the SSF,but the characteristics of the multi-time scale,periodic and abrupt change were mainly influenced by climate variations.
