A highly sensitive spectrophotometric method for determination of selenium(IV) has been developed.It has been based on Se(IV) oxidation of I - in a weak acid medium and formation of the 1∶1 ion associatin complex of I - with Butylrhodamine B in the presence of poly(vinyl alcohol).The wavelength of maximum absorbance of this complex was at 590nm,The molar absorptivity was 2.57 ×10 5L.mol -1 ·cm -1 and Beer’s law was obeyed in the concentration range of 40～500ng/mL.The detection limit was 40ng/mL.Interfering ions were eliminated by using thiohydroxy cotton so that the selectivity of this method was good.The color system was used to determine the microamounts of Se in the liver of dophine and huangqi.Satisfactory results were obtained.
A new highly sensitive color reaction of selenium(Ⅳ) with potassium iodide and malachite green and arabic gum has been studied.The optimum conditions and the main characters of the system have been determined.The apparent molar absorptivity of the complex is 2.5×10 5L·mol -1 ·cm -1 at 660nm.Beers law is applicable over a range of 0 25μg/25ml for Se(Ⅳ).The method has been amployed for the determination of selenium(Ⅳ) in Chinese herbal medicines,Lingzhi and Huangqi,the results being satisfactory.
A high performance red-sensitive holographic recording material was studied.After acrylic acid was added into PPA system,the holograms of high diffraction efficiency,which was stable in high humidty environment for a long time,were obtained.
