[Objective] The paper was to establish a HPLC method for quantitative determination of 80% pymetrozine·nitenpyram WG. [Method] With the mixture of acetonitrile, water and phosphate buffer (volume ratio 10:80...[Objective] The paper was to establish a HPLC method for quantitative determination of 80% pymetrozine·nitenpyram WG. [Method] With the mixture of acetonitrile, water and phosphate buffer (volume ratio 10:80:10) as the mobile phase, pymetrozine and nitenpyram in samples were separated by ODS-2 reversed phase column, and detected by UV detector at 250 nm. In addition, the results were quantified by external standard method. [Result] The linear correlation coefficients of pymetrozine and nitenpyram were 0.9995 and 0.9998; the standard deviations were 0.29 and 0.22; the coefficients of variation were 0.51% and 1.21%; and the average recoveries were 100.7% and 99.1%, respectively. [Conclusion] The method is fast and simple, and can effectively separate pymetrozine and nitenpyram, with high precision and accuracy and good linear relation.展开更多
A simple and efficient method was developed for fabricating spherical granules of CuO catalyst via a three-step procedure. In the first step, copper oxide nanoparticles were synthesized by hydrothermal decomposition o...A simple and efficient method was developed for fabricating spherical granules of CuO catalyst via a three-step procedure. In the first step, copper oxide nanoparticles were synthesized by hydrothermal decomposition of copper nitrate solution under supercritical condition. Then, they were immobilized in the polymeric matrix of calcium alginate, and followed by high-temperature calcination in an air stream as the third step, in which carbonaceous materials were oxidized, to result in a pebble-type catalyst of high porosity. The produced CuO nanoparticles were characterized by transmission electron microscopy (TEM) that revealed an average size of 5 nm, X-ray diffractometry (XRD), and thermo gravimetric (TG) analysis. The catalysts were further investigated by BET test for measurement of their surface area, and by temperature-programmed reduction analysis (H2-TPR) for determination of catalytic activity. The results demonstrated that immobilization of the CuO nanoparticle in the polymeric matrix of calcium alginate, followed by calcination at elevated temperatures, could result in notable mechanical strength and enhanced catalytic activity due to preservation of the high surface area, both valuable for practical applications.展开更多
文摘[Objective] The paper was to establish a HPLC method for quantitative determination of 80% pymetrozine·nitenpyram WG. [Method] With the mixture of acetonitrile, water and phosphate buffer (volume ratio 10:80:10) as the mobile phase, pymetrozine and nitenpyram in samples were separated by ODS-2 reversed phase column, and detected by UV detector at 250 nm. In addition, the results were quantified by external standard method. [Result] The linear correlation coefficients of pymetrozine and nitenpyram were 0.9995 and 0.9998; the standard deviations were 0.29 and 0.22; the coefficients of variation were 0.51% and 1.21%; and the average recoveries were 100.7% and 99.1%, respectively. [Conclusion] The method is fast and simple, and can effectively separate pymetrozine and nitenpyram, with high precision and accuracy and good linear relation.
基金for financial and instrumental supports of this project
文摘A simple and efficient method was developed for fabricating spherical granules of CuO catalyst via a three-step procedure. In the first step, copper oxide nanoparticles were synthesized by hydrothermal decomposition of copper nitrate solution under supercritical condition. Then, they were immobilized in the polymeric matrix of calcium alginate, and followed by high-temperature calcination in an air stream as the third step, in which carbonaceous materials were oxidized, to result in a pebble-type catalyst of high porosity. The produced CuO nanoparticles were characterized by transmission electron microscopy (TEM) that revealed an average size of 5 nm, X-ray diffractometry (XRD), and thermo gravimetric (TG) analysis. The catalysts were further investigated by BET test for measurement of their surface area, and by temperature-programmed reduction analysis (H2-TPR) for determination of catalytic activity. The results demonstrated that immobilization of the CuO nanoparticle in the polymeric matrix of calcium alginate, followed by calcination at elevated temperatures, could result in notable mechanical strength and enhanced catalytic activity due to preservation of the high surface area, both valuable for practical applications.