In order to develop a quick, efficient and sensitive valence analysis method of vanadium(Ⅴ), the highperformance liquid chromatography(HPLC) was utilized to separate and quantify EDTA-complexed Ⅴ(Ⅲ), Ⅴ(Ⅳ) and Ⅴ(...In order to develop a quick, efficient and sensitive valence analysis method of vanadium(Ⅴ), the highperformance liquid chromatography(HPLC) was utilized to separate and quantify EDTA-complexed Ⅴ(Ⅲ), Ⅴ(Ⅳ) and Ⅴ(Ⅴ) ions. The influence of EDTA, TBAOH, solution pH and organic modifier on retention behavior of V-EDTA complexes was investigated. Complexed Ⅴ(Ⅲ), Ⅴ(Ⅳ) and Ⅴ(Ⅴ) ions can be separated and quantified in 5 min, with detection limits of 0.04 mg/L Ⅴ(Ⅲ), 0.07 mg/L Ⅴ(Ⅳ), and 0.06 mg/L Ⅴ(Ⅴ), respecti vely. The established method is applied to analyzing the hazardous waste of V-Cr-bearing reducing slag and results demonstrate 49.94% of its Ⅴ element to be toxic Ⅴ(Ⅴ). This work opens a new avenue for quick and accurate toxicity assessment of hazardous wastes containing multivalent heavy metals.展开更多
A homogeneous crack-free nano- or meso-porous silica films on silicon was fabricated by colloidal silica sol derived by hydrolyzing tetraethyl orthosilicate (TEOS) catalyzing with (C4H9)4N+OH- in water medium. The sol...A homogeneous crack-free nano- or meso-porous silica films on silicon was fabricated by colloidal silica sol derived by hydrolyzing tetraethyl orthosilicate (TEOS) catalyzing with (C4H9)4N+OH- in water medium. The solution with ratio of H2O/TEOS15, R4N+ and glycerol as templates, combining with the hydrolyzed intermediate, controlled the silica aggregating; the templated silica film with heterostructure was developed into homogeneous nano-porous then meso-porous silica films after being annealed from 750 C to 850 C; the formation mechanism of the porous silica films was discussed; morphologies of the silica films were characterized. The refractive indexes of the porous silica films were 1.2561.458, the thermal conductivity < 0.7 W/m/K. The fabricating procedure and the sequence had not been reported before.展开更多
基金the National Key Research and Development Program of China (No. 2020YFC1909701)the National Natural Science Foundation of China (No. 52074050)Chongqing Science and Technology Bureau (Nos. cstc2019jcyjjqX0006, cstc2021ycjhbgzxm0075)。
文摘In order to develop a quick, efficient and sensitive valence analysis method of vanadium(Ⅴ), the highperformance liquid chromatography(HPLC) was utilized to separate and quantify EDTA-complexed Ⅴ(Ⅲ), Ⅴ(Ⅳ) and Ⅴ(Ⅴ) ions. The influence of EDTA, TBAOH, solution pH and organic modifier on retention behavior of V-EDTA complexes was investigated. Complexed Ⅴ(Ⅲ), Ⅴ(Ⅳ) and Ⅴ(Ⅴ) ions can be separated and quantified in 5 min, with detection limits of 0.04 mg/L Ⅴ(Ⅲ), 0.07 mg/L Ⅴ(Ⅳ), and 0.06 mg/L Ⅴ(Ⅴ), respecti vely. The established method is applied to analyzing the hazardous waste of V-Cr-bearing reducing slag and results demonstrate 49.94% of its Ⅴ element to be toxic Ⅴ(Ⅴ). This work opens a new avenue for quick and accurate toxicity assessment of hazardous wastes containing multivalent heavy metals.
文摘A homogeneous crack-free nano- or meso-porous silica films on silicon was fabricated by colloidal silica sol derived by hydrolyzing tetraethyl orthosilicate (TEOS) catalyzing with (C4H9)4N+OH- in water medium. The solution with ratio of H2O/TEOS15, R4N+ and glycerol as templates, combining with the hydrolyzed intermediate, controlled the silica aggregating; the templated silica film with heterostructure was developed into homogeneous nano-porous then meso-porous silica films after being annealed from 750 C to 850 C; the formation mechanism of the porous silica films was discussed; morphologies of the silica films were characterized. The refractive indexes of the porous silica films were 1.2561.458, the thermal conductivity < 0.7 W/m/K. The fabricating procedure and the sequence had not been reported before.
