A new process was proposed for removing the nitrogen oxides(NO x) from the CO 2 waste gases from the lime torrefied ratary furnace in Shanghai Baoshan Steel and Iron Company by means of absorption method of aqueous ur...A new process was proposed for removing the nitrogen oxides(NO x) from the CO 2 waste gases from the lime torrefied ratary furnace in Shanghai Baoshan Steel and Iron Company by means of absorption method of aqueous urea solution in order to recover highly pure CO 2 for producing high quality beverage. The result obtained shows that the concentration of nitrogen oxides can be decreased from 6^5×10 -4 {mol/L} to below 2.0×10 -6 mol/L, the removing rate was over 99%. In the experiment, we made NO coming from the reaction NO 2 +H 2O be all oxidized to NO 2 by using a special oxidized method, which was the key step for removing nitrogen oxides.展开更多
In this study, an ultrasonic nebulizer unit was established to improve the quantitative analysis ability of laser-induced breakdown spectroscopy （LIBS） for liquid samples detection, using solutions of the heavy meta...In this study, an ultrasonic nebulizer unit was established to improve the quantitative analysis ability of laser-induced breakdown spectroscopy （LIBS） for liquid samples detection, using solutions of the heavy metal element Pb as an example. An analytical procedure was designed to guarantee the stability and repeatability of the LIBS signal. A series of experiments were carried out strictly according to the procedure. The experimental parameters were optimized based on studies of the pulse energy influence and temporal evolution of the emission features. The plasma temperature and electron density were calculated to confirm the LTE state of the plasma. Normalizing the intensities by background was demonstrated to be an appropriate method in this work. The linear range of this system for Pb analysis was confirmed over a concentration range of 0-4,150ppm by measuring 12 samples with different concentrations. The correlation coefficient of the fitted calibration curve was as high as 99.94% in the linear range, and the LOD of Pb was confirmed as 2.93ppm. Concentration prediction experiments were performed on a further six samples. The excellent quantitative ability of the system was demonstrated by comparison of the real and predicted concentrations of the samples. The lowest relative error was 0.043% and the highest was no more than 7.1%.展开更多
文摘A new process was proposed for removing the nitrogen oxides(NO x) from the CO 2 waste gases from the lime torrefied ratary furnace in Shanghai Baoshan Steel and Iron Company by means of absorption method of aqueous urea solution in order to recover highly pure CO 2 for producing high quality beverage. The result obtained shows that the concentration of nitrogen oxides can be decreased from 6^5×10 -4 {mol/L} to below 2.0×10 -6 mol/L, the removing rate was over 99%. In the experiment, we made NO coming from the reaction NO 2 +H 2O be all oxidized to NO 2 by using a special oxidized method, which was the key step for removing nitrogen oxides.
基金Financial support from the National Natural Science Foundation of China （Grant No. 11104153） is highly acknowledged.
文摘In this study, an ultrasonic nebulizer unit was established to improve the quantitative analysis ability of laser-induced breakdown spectroscopy （LIBS） for liquid samples detection, using solutions of the heavy metal element Pb as an example. An analytical procedure was designed to guarantee the stability and repeatability of the LIBS signal. A series of experiments were carried out strictly according to the procedure. The experimental parameters were optimized based on studies of the pulse energy influence and temporal evolution of the emission features. The plasma temperature and electron density were calculated to confirm the LTE state of the plasma. Normalizing the intensities by background was demonstrated to be an appropriate method in this work. The linear range of this system for Pb analysis was confirmed over a concentration range of 0-4,150ppm by measuring 12 samples with different concentrations. The correlation coefficient of the fitted calibration curve was as high as 99.94% in the linear range, and the LOD of Pb was confirmed as 2.93ppm. Concentration prediction experiments were performed on a further six samples. The excellent quantitative ability of the system was demonstrated by comparison of the real and predicted concentrations of the samples. The lowest relative error was 0.043% and the highest was no more than 7.1%.
