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
The concentrations of bovine serum albumin,gliadin,bovine hemoglobim,mucin,lysozyme and proteins mixture in solutions were determined by spectrophotometric assay at 230 nm(A230 assay).For all the sample solutions of p...The concentrations of bovine serum albumin,gliadin,bovine hemoglobim,mucin,lysozyme and proteins mixture in solutions were determined by spectrophotometric assay at 230 nm(A230 assay).For all the sample solutions of pure proteins,the linear range of A230assay was 25～250μg·mL-1,and salt had little influence on this method.For the solutions containing two kinds of proteins,the mass ratio of the proteins affected the result of determination.For the solutions of proteins mixture,the average recovery rate(n=6)of A230assay was 101.6%(99.04%～109.1%)with RSD=3.82%.As a result,a new effective method to determine protein concentration was suggested.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The concentrations of bovine serum albumin,gliadin,bovine hemoglobim,mucin,lysozyme and proteins mixture in solutions were determined by spectrophotometric assay at 230 nm(A230 assay).For all the sample solutions of pure proteins,the linear range of A230assay was 25～250μg·mL-1,and salt had little influence on this method.For the solutions containing two kinds of proteins,the mass ratio of the proteins affected the result of determination.For the solutions of proteins mixture,the average recovery rate(n=6)of A230assay was 101.6%(99.04%～109.1%)with RSD=3.82%.As a result,a new effective method to determine protein concentration was suggested.
