A new method for the separation and detection of trace metal impurities in cerium oxide (CeO_2) using HPLC combined with electrothermal vaporization (ETV)-ICP-AES was developed. This combination links the high separat...A new method for the separation and detection of trace metal impurities in cerium oxide (CeO_2) using HPLC combined with electrothermal vaporization (ETV)-ICP-AES was developed. This combination links the high separation power of HPLC and high sensitivity of ETV-ICP-AES. The 2-ethylhexyl hydrogen 2-ethylhexylphosphate (P_(507)) resin was used as stationary phase for the separation of metallic impurities in order to eliminate severe spectral interferences of the matrix. The dilute nitric acid was adopted as mobile phase for eluting Cu, Mn, Ni and La. The separation process can be accomplished in about 30 min. After concentrating the eluate by evaporation, the trace impurities were determined by using ETV-ICP-AES with the addition of 6% PTFE slurry as chemical modifier. The proposed method was applied to the analysis of CeO_2 with satisfactory recoveries.展开更多
Global food prices are going up,and the timing couldn't be worse.In Indonesia,tofu is 30%more expensive than it was in December 2020.In Brazil,the price of local mainstay(主要依靠)turtle beans is up 54%compared to...Global food prices are going up,and the timing couldn't be worse.In Indonesia,tofu is 30%more expensive than it was in December 2020.In Brazil,the price of local mainstay(主要依靠)turtle beans is up 54%compared to last January.In Russia,consumers are paying 61%more for sugar than a year ago.展开更多
文摘A new method for the separation and detection of trace metal impurities in cerium oxide (CeO_2) using HPLC combined with electrothermal vaporization (ETV)-ICP-AES was developed. This combination links the high separation power of HPLC and high sensitivity of ETV-ICP-AES. The 2-ethylhexyl hydrogen 2-ethylhexylphosphate (P_(507)) resin was used as stationary phase for the separation of metallic impurities in order to eliminate severe spectral interferences of the matrix. The dilute nitric acid was adopted as mobile phase for eluting Cu, Mn, Ni and La. The separation process can be accomplished in about 30 min. After concentrating the eluate by evaporation, the trace impurities were determined by using ETV-ICP-AES with the addition of 6% PTFE slurry as chemical modifier. The proposed method was applied to the analysis of CeO_2 with satisfactory recoveries.
文摘Global food prices are going up,and the timing couldn't be worse.In Indonesia,tofu is 30%more expensive than it was in December 2020.In Brazil,the price of local mainstay(主要依靠)turtle beans is up 54%compared to last January.In Russia,consumers are paying 61%more for sugar than a year ago.