The Cr（III） sorption experiments onto Kappaphycus alvarezii waste biomass were conducted at different pH values（2-6） under the conditions of initial metal concentration of 10-50 mg/L and the chemical compositions ...The Cr（III） sorption experiments onto Kappaphycus alvarezii waste biomass were conducted at different pH values（2-6） under the conditions of initial metal concentration of 10-50 mg/L and the chemical compositions of Cr-Cu and Cr-Cd.The Cr（III） sorption capacities were slightly dependent on pH,and the maximum sorption capacity was 0.86 mg/g at pH 3.The sorption capacities increased with increase in the initial metal concentration,whereas it was suppressed by the presence of Cu（II） and Cd（III） in the solution.The Cr（III） sorption equilibrium was evaluated using Langmuir,Freundlich and BET isotherms.The sorption mechanisms were characterised using scanning electron microscopy and Fourier transform infrared spectroscopy.The main mechanisms were ion exchange coupled with a complexation mechanism.Kappaphycus alvarezii waste biomass represents a potential for Cr（III） ion removal from aqueous solution.展开更多
A simple and rapid optical biosensor for the determination of ammonium was developed by immobilization of gluta-mate dehydrogenase (GLDH) and diaphorase (Dph) in chitosan film coated on a glass slide employing thiazol...A simple and rapid optical biosensor for the determination of ammonium was developed by immobilization of gluta-mate dehydrogenase (GLDH) and diaphorase (Dph) in chitosan film coated on a glass slide employing thiazolyl blue tetrazolium bromide (MTT) as a color indicator. The developed biosensor displays a purple color formation of formazan attributed to the unreacted NADH in the reaction system in the presence of ammonium. The color intensity was found to decrease proportionally with the increase of ammonium concentrations after 10 min exposure. The linearity of the biosensor towards ammonium was in the range of 16.8 – 70 μM (R2 = 0.9955) with detection limit of 11 μM. A good agreement (R2 = 0.9984) with indothymol method was obtained in the measurement of fish pond water samples. The effect of potential interferences such as metals ion has also been evaluated.展开更多
基金supported by a Research University Grant from UKM-GUP-NBT-08-27-104
文摘The Cr（III） sorption experiments onto Kappaphycus alvarezii waste biomass were conducted at different pH values（2-6） under the conditions of initial metal concentration of 10-50 mg/L and the chemical compositions of Cr-Cu and Cr-Cd.The Cr（III） sorption capacities were slightly dependent on pH,and the maximum sorption capacity was 0.86 mg/g at pH 3.The sorption capacities increased with increase in the initial metal concentration,whereas it was suppressed by the presence of Cu（II） and Cd（III） in the solution.The Cr（III） sorption equilibrium was evaluated using Langmuir,Freundlich and BET isotherms.The sorption mechanisms were characterised using scanning electron microscopy and Fourier transform infrared spectroscopy.The main mechanisms were ion exchange coupled with a complexation mechanism.Kappaphycus alvarezii waste biomass represents a potential for Cr（III） ion removal from aqueous solution.
文摘A simple and rapid optical biosensor for the determination of ammonium was developed by immobilization of gluta-mate dehydrogenase (GLDH) and diaphorase (Dph) in chitosan film coated on a glass slide employing thiazolyl blue tetrazolium bromide (MTT) as a color indicator. The developed biosensor displays a purple color formation of formazan attributed to the unreacted NADH in the reaction system in the presence of ammonium. The color intensity was found to decrease proportionally with the increase of ammonium concentrations after 10 min exposure. The linearity of the biosensor towards ammonium was in the range of 16.8 – 70 μM (R2 = 0.9955) with detection limit of 11 μM. A good agreement (R2 = 0.9984) with indothymol method was obtained in the measurement of fish pond water samples. The effect of potential interferences such as metals ion has also been evaluated.
