A new method of 2-amino-4-nitrophenol and 2-amino-5-nitrophenol in hair dye determined by liquid chromatography-mass spectrometry.Chromatographic separation was carried out on a Atlantis C18 (2.1 mm i.d.×150 mm,5...A new method of 2-amino-4-nitrophenol and 2-amino-5-nitrophenol in hair dye determined by liquid chromatography-mass spectrometry.Chromatographic separation was carried out on a Atlantis C18 (2.1 mm i.d.×150 mm,5 μm)column with gradient elution with methanol-acetonitrile at a flow rate 0.2 mL/min.The mass spectrometry was operated in the positive electrospray ionization mode.Quantity was performed using multiple reaction monitoring of the product ion transitions m/z153.0>m/z106(17eV) for 2-amino-4-nitrophenol and m/z153.0>m/z122(15eV) for 2-amino-5-nitrophenol.Linearity of peak was obtained over a range of concentration is from 0.2 to 100 mg/L.The limit is 0.2 mg/L of the method.The proposed method was accurate and rapid with wide linear range.The repeatability and the reproducibility of the method were excellent.It has been applied to detect the real with satisfactory results.展开更多
A novel technology for lead removal with nonliving Rhizopus oligosporus immobilized in calcium alginate was studied. The results show that the main influencing factors include pH value and interfering cations. pH valu...A novel technology for lead removal with nonliving Rhizopus oligosporus immobilized in calcium alginate was studied. The results show that the main influencing factors include pH value and interfering cations. pH value has different effects on biosorption of various heavy metals and lead adsorption can be proceeded by controlling pH value in a range of 2–5; interfering cations especially Cu(II) can make the adsorption amount of Pb(II) decrease by immobilized Rhizopus oligosporus. Desorption efficiency of different eluants and kinetics were investigated. Citrate acid with concentration of 0.3 mol ? L?1 is the best for the elution of Pb(II) and desorption rate is over 98%when the reaction equilibrium reaches 3 h. Immobilized biomass keeps high lead biosorption capacity after five cycles of regeneration.展开更多
文摘A new method of 2-amino-4-nitrophenol and 2-amino-5-nitrophenol in hair dye determined by liquid chromatography-mass spectrometry.Chromatographic separation was carried out on a Atlantis C18 (2.1 mm i.d.×150 mm,5 μm)column with gradient elution with methanol-acetonitrile at a flow rate 0.2 mL/min.The mass spectrometry was operated in the positive electrospray ionization mode.Quantity was performed using multiple reaction monitoring of the product ion transitions m/z153.0>m/z106(17eV) for 2-amino-4-nitrophenol and m/z153.0>m/z122(15eV) for 2-amino-5-nitrophenol.Linearity of peak was obtained over a range of concentration is from 0.2 to 100 mg/L.The limit is 0.2 mg/L of the method.The proposed method was accurate and rapid with wide linear range.The repeatability and the reproducibility of the method were excellent.It has been applied to detect the real with satisfactory results.
文摘A novel technology for lead removal with nonliving Rhizopus oligosporus immobilized in calcium alginate was studied. The results show that the main influencing factors include pH value and interfering cations. pH value has different effects on biosorption of various heavy metals and lead adsorption can be proceeded by controlling pH value in a range of 2–5; interfering cations especially Cu(II) can make the adsorption amount of Pb(II) decrease by immobilized Rhizopus oligosporus. Desorption efficiency of different eluants and kinetics were investigated. Citrate acid with concentration of 0.3 mol ? L?1 is the best for the elution of Pb(II) and desorption rate is over 98%when the reaction equilibrium reaches 3 h. Immobilized biomass keeps high lead biosorption capacity after five cycles of regeneration.
