In the medium of 0.18～1.08 mol·L^(-1) sulfuric acid, cerium(Ⅳ) has the color-fading effect on DBC-arsenazo. The apparent molar absorptivity of the color-fading reaction is ε _(530 nm)=1.03×10~4 L·mo...In the medium of 0.18～1.08 mol·L^(-1) sulfuric acid, cerium(Ⅳ) has the color-fading effect on DBC-arsenazo. The apparent molar absorptivity of the color-fading reaction is ε _(530 nm)=1.03×10~4 L·mol^(-1)·cm^(-1). Beer′s law is obeyed over the range of 1.20～12.0 μg·ml^(-1) of Ce (Ⅳ) which shows a linear relationship with the decrease in the absorbance of the colored solution. The effect of thirty-six coexisting ions was studied. The method was applied to the determination of the trace amount of cerium in water samples and has the advantage of high accuracy and good selectivity.展开更多
A new inhibition kinetic spectrophotometric medod for the determination of trace nitrobenzene was proposed,based on the inhibit effecy of initrobenzene on decoloration reaction of methyl orange (MO) for the oxidation ...A new inhibition kinetic spectrophotometric medod for the determination of trace nitrobenzene was proposed,based on the inhibit effecy of initrobenzene on decoloration reaction of methyl orange (MO) for the oxidation of potassium iodate in the solution with pH=2.20 of hydrochloric acid and the activator stannous chloride.The kinetic condition of this reaction was investigated.Addition of the cetyl trimethyl aminonium bromide (CTMAB) can increase the sensitivity of the determination.The detection limit is 1.82×10 -7 g·L -1 ,ε 515 =1.2×10 5L·mol -1 ·cm -1 and the calibration graph is linear from 0.02～30.0μg·ml -1 nitrobenzene.The interference of aniline was eliminated by the addition of distillation in acidic solution.It was applied to the detemination of trace nitrobenzene in waste water with RSD=1.6%～2.3%.展开更多
文摘In the medium of 0.18～1.08 mol·L^(-1) sulfuric acid, cerium(Ⅳ) has the color-fading effect on DBC-arsenazo. The apparent molar absorptivity of the color-fading reaction is ε _(530 nm)=1.03×10~4 L·mol^(-1)·cm^(-1). Beer′s law is obeyed over the range of 1.20～12.0 μg·ml^(-1) of Ce (Ⅳ) which shows a linear relationship with the decrease in the absorbance of the colored solution. The effect of thirty-six coexisting ions was studied. The method was applied to the determination of the trace amount of cerium in water samples and has the advantage of high accuracy and good selectivity.
文摘A new inhibition kinetic spectrophotometric medod for the determination of trace nitrobenzene was proposed,based on the inhibit effecy of initrobenzene on decoloration reaction of methyl orange (MO) for the oxidation of potassium iodate in the solution with pH=2.20 of hydrochloric acid and the activator stannous chloride.The kinetic condition of this reaction was investigated.Addition of the cetyl trimethyl aminonium bromide (CTMAB) can increase the sensitivity of the determination.The detection limit is 1.82×10 -7 g·L -1 ,ε 515 =1.2×10 5L·mol -1 ·cm -1 and the calibration graph is linear from 0.02～30.0μg·ml -1 nitrobenzene.The interference of aniline was eliminated by the addition of distillation in acidic solution.It was applied to the detemination of trace nitrobenzene in waste water with RSD=1.6%～2.3%.
