A solid phase extraction procedure of methomyl and thiodicarb from environmental water was presented. This method utilizes a 40—60 mesh activated carbon cartridge and high performance liquid chromatography (HPLC). Th...A solid phase extraction procedure of methomyl and thiodicarb from environmental water was presented. This method utilizes a 40—60 mesh activated carbon cartridge and high performance liquid chromatography (HPLC). The 40—60 mesh activated carbon works faster and yield higher adsorption efficiency. Detection limits of methomyl and thiodicarb in environmental water are 0 1 μg/L and 0 2 μg/L, respectively. Average recoveries of fortified methomyl and thiodicarb in water are in the range of 90 7%—98 8% and 88 9%—103 6%, respectively. The relative standard deviations are lower than 7%. This method is simple, rapid, accurate and precise.展开更多
A simple and selective method was developed for the preconcentration, separation, and determination of trace amounts of As（Ⅲ） in an aqueous solution by solid phase extraction combined with graphite furnace atomic a...A simple and selective method was developed for the preconcentration, separation, and determination of trace amounts of As（Ⅲ） in an aqueous solution by solid phase extraction combined with graphite furnace atomic absorption spectrometry. Activated carbon （AC） was modified by sodium diethyldithiocarbamate （NaDDTC） and then used as a new, stable and easily prepared solid sorbent in a mini column for the extraction of As（Ⅲ） in aqueous solution. Factors influencing the sorption and desorption of As（Ⅲ）, such as volume and concentration of eluent, sam- ple pH, flow rate and effect of interfering ions on the recovery of As（Ⅲ） have been systemically investigated. At pH 2.0 As（Ⅲ） could be adsorbed quantitatively by NaDDTC-AC, and then eluted completely with 2 mL of 3.0 moloL 1 HNO3. The amount of eluted As（Ⅲ） was measured using graphite furnace atomic absorption spectrometry. The detection limit of As（Ⅲ） was 0.04 ng·mL-1 with enrichment factor of 100 and the relative standard deviation （RSD, n=8） was 1.58% at 10 ng·mL-1 level.展开更多
文摘A solid phase extraction procedure of methomyl and thiodicarb from environmental water was presented. This method utilizes a 40—60 mesh activated carbon cartridge and high performance liquid chromatography (HPLC). The 40—60 mesh activated carbon works faster and yield higher adsorption efficiency. Detection limits of methomyl and thiodicarb in environmental water are 0 1 μg/L and 0 2 μg/L, respectively. Average recoveries of fortified methomyl and thiodicarb in water are in the range of 90 7%—98 8% and 88 9%—103 6%, respectively. The relative standard deviations are lower than 7%. This method is simple, rapid, accurate and precise.
文摘A simple and selective method was developed for the preconcentration, separation, and determination of trace amounts of As（Ⅲ） in an aqueous solution by solid phase extraction combined with graphite furnace atomic absorption spectrometry. Activated carbon （AC） was modified by sodium diethyldithiocarbamate （NaDDTC） and then used as a new, stable and easily prepared solid sorbent in a mini column for the extraction of As（Ⅲ） in aqueous solution. Factors influencing the sorption and desorption of As（Ⅲ）, such as volume and concentration of eluent, sam- ple pH, flow rate and effect of interfering ions on the recovery of As（Ⅲ） have been systemically investigated. At pH 2.0 As（Ⅲ） could be adsorbed quantitatively by NaDDTC-AC, and then eluted completely with 2 mL of 3.0 moloL 1 HNO3. The amount of eluted As（Ⅲ） was measured using graphite furnace atomic absorption spectrometry. The detection limit of As（Ⅲ） was 0.04 ng·mL-1 with enrichment factor of 100 and the relative standard deviation （RSD, n=8） was 1.58% at 10 ng·mL-1 level.
