Because of the effect of silicon on the formation of oxide scale, black strip defect is common on the surface of compact strip production (CSP) hot-rolled silicon steel, which leads to difficulty in pickling process...Because of the effect of silicon on the formation of oxide scale, black strip defect is common on the surface of compact strip production (CSP) hot-rolled silicon steel, which leads to difficulty in pickling process compared with plain carbon steels. Although high-temperature oxidation of Fe-Si alloy has been discussed a lot, few studies have explained the mechanism of black strip defect generated on the surface of hot-rolled silicon steel and proposed means to prevent it effectively. Thermogravimetric analyzer (TGA) is used to simulate oxidation of Fe-2.2Si alloy for 30 min under air condition, and temperature range is from 1000 to 1150 ℃. Effect of rolling deformation on scale morphology is also discussed. Electron probe microanalysis (EPMA) is used to analyze cross-sectional morphology and elemental distribution of the oxide scale. Schematic diagram of formation of black strip defect is obtained, which helps to provide theoretic basis for proposing of solutions for the Problem. It is proposed that lowering furnace tem-perature and shortening time to stay at high teniperature condition after rolling will be helpful tO relieve the black strip problem.展开更多
Cyclic voltammograms of reactive black5 (RB5) at different pHs in the range 1.0 - 13.0 on multiwall carbon nanotube modified glassy carbon electrode revealed the presence of one well-defined irreversible anodic peak a...Cyclic voltammograms of reactive black5 (RB5) at different pHs in the range 1.0 - 13.0 on multiwall carbon nanotube modified glassy carbon electrode revealed the presence of one well-defined irreversible anodic peak around 975 mV in acidic and neutral pHs. Adsorption controlled oxidation observed at acidic pH 1.0 resulted in the maximum peak current response in cyclic voltammograms. A systematic differential pulse stripping voltammetric studies were carried out using the modified electrode at pH 1.0. The accumulation parameters, accumulation potential and time were optimized for maximum adsorption of the dye which was ascertained from the SEM photographs and XRD results. The stripping parameters were optimized and calibration was made under optimum conditions. The range of study was from 0.5 ppm to 100 ppm and the lower limit of determination was 100 ppm. Five identical experiments were carried out and the RSD value obtained was 2.5% suggesting good reproducibility. The proposed method was successfully applied to determine the concentration of dye in the fabric and wastewater after dyeing.展开更多
基金Item Sponsored by National High-Tech Research and Development Program(863Program)of China(2011BAE13B04)Fundamental Research Funds for Central Universities of China(N100307006)
文摘Because of the effect of silicon on the formation of oxide scale, black strip defect is common on the surface of compact strip production (CSP) hot-rolled silicon steel, which leads to difficulty in pickling process compared with plain carbon steels. Although high-temperature oxidation of Fe-Si alloy has been discussed a lot, few studies have explained the mechanism of black strip defect generated on the surface of hot-rolled silicon steel and proposed means to prevent it effectively. Thermogravimetric analyzer (TGA) is used to simulate oxidation of Fe-2.2Si alloy for 30 min under air condition, and temperature range is from 1000 to 1150 ℃. Effect of rolling deformation on scale morphology is also discussed. Electron probe microanalysis (EPMA) is used to analyze cross-sectional morphology and elemental distribution of the oxide scale. Schematic diagram of formation of black strip defect is obtained, which helps to provide theoretic basis for proposing of solutions for the Problem. It is proposed that lowering furnace tem-perature and shortening time to stay at high teniperature condition after rolling will be helpful tO relieve the black strip problem.
文摘Cyclic voltammograms of reactive black5 (RB5) at different pHs in the range 1.0 - 13.0 on multiwall carbon nanotube modified glassy carbon electrode revealed the presence of one well-defined irreversible anodic peak around 975 mV in acidic and neutral pHs. Adsorption controlled oxidation observed at acidic pH 1.0 resulted in the maximum peak current response in cyclic voltammograms. A systematic differential pulse stripping voltammetric studies were carried out using the modified electrode at pH 1.0. The accumulation parameters, accumulation potential and time were optimized for maximum adsorption of the dye which was ascertained from the SEM photographs and XRD results. The stripping parameters were optimized and calibration was made under optimum conditions. The range of study was from 0.5 ppm to 100 ppm and the lower limit of determination was 100 ppm. Five identical experiments were carried out and the RSD value obtained was 2.5% suggesting good reproducibility. The proposed method was successfully applied to determine the concentration of dye in the fabric and wastewater after dyeing.