An optimized and validated spectrophotometric method has been developed for the determination of cefixime in pharmaceutical formulations. The method is based on the complexa- tion reaction between cefixime and palladi...An optimized and validated spectrophotometric method has been developed for the determination of cefixime in pharmaceutical formulations. The method is based on the complexa- tion reaction between cefixime and palladium ion in the presence of acidic buffer solution (pH 3) in ethanol-distilled water medium at room temperature. The complex absorbed maximally at 352 nm. Beer's law is obeyed in the working concentration range of 2.5-35 μg/mL with apparent molar absorptivity of 1.015×104 L/mol cm and Sandell's sensitivity of 0.001 μg/cm2/0.001 absorbance unit. The limits of detection and quantitation for the proposed method are 0.175 and 0.583μg/mL, respectively. The effect of common excipients used as additives has been studied in the determination of cefixime. The proposed method has been successfully applied for the determina- tion of cefixime in pharmaceutical formulations. The results obtained by the proposed method were statistically compared with the reference method using t and F values and found no significant difference between the two methods.展开更多
The purpose of the investigation is the study of the physico-chemical properties and electro-catalytic characteristics of the Nafion and MF-4SK membranes with the author’s nanoparticles (A. Revina, 2008) incorporated...The purpose of the investigation is the study of the physico-chemical properties and electro-catalytic characteristics of the Nafion and MF-4SK membranes with the author’s nanoparticles (A. Revina, 2008) incorporated into the perfluoro- sulphonated cationic membranes. An important advance in the creation of new nano-composite materials with poly-functional activity is the inclusion of nanoparticles of various metals (Pd, Pt, Ag) in these membranes. Polymer ion exchange membranes represent widely applicable materials in various areas of modern nanotechnologies. The obtained nanocomposites on the base of included nanoparticles have the perspective properties and polyfunctional activity for the applications.展开更多
The Spent loaded-Pd cordierite honeycomb ceramic automotive catalytic converters,which were roasted to remove the deposit charcoal and other organic compounds,and were milled less then 100 mesh were reduced by HCOOH,w...The Spent loaded-Pd cordierite honeycomb ceramic automotive catalytic converters,which were roasted to remove the deposit charcoal and other organic compounds,and were milled less then 100 mesh were reduced by HCOOH,which PdO was reduced to Pd and then the Pd was selectively leached with HCl-NaClO3.Palladium was determined by DDO spectrophotometry.In this paper,the determined results of several leaching methods were compared.The key factors which affected the Pd leaching by the system of HCl-NaClO3 were discussed and the optimal leaching conditions were proposed.The results indicated the Pd in automotive catalysts can be quantitatively analyzed by DDO spectrophotometry with HCl-NaClO3 for Pd leaching and at the same time the palladium of Pd-catalysts can be quantitatively determined.展开更多
研究了在聚乙二醇 PAR 硫酸铵体系中萃取光度法测定钯的条件.在pH7.40的EDTA NaOH介质中,Pd(II) PAR被萃取到聚乙二醇相,最大吸收波长为525nm,摩尔吸光系数为3.71×104L·mol-1·cm-1,钯含量在0~26.4μg/10.0mL范围内符合...研究了在聚乙二醇 PAR 硫酸铵体系中萃取光度法测定钯的条件.在pH7.40的EDTA NaOH介质中,Pd(II) PAR被萃取到聚乙二醇相,最大吸收波长为525nm,摩尔吸光系数为3.71×104L·mol-1·cm-1,钯含量在0~26.4μg/10.0mL范围内符合比耳定律,检出限为0.029μg/10.0mL.方法用于碳钯催化剂和矿样中钯分离测定,结果满意.展开更多
文摘An optimized and validated spectrophotometric method has been developed for the determination of cefixime in pharmaceutical formulations. The method is based on the complexa- tion reaction between cefixime and palladium ion in the presence of acidic buffer solution (pH 3) in ethanol-distilled water medium at room temperature. The complex absorbed maximally at 352 nm. Beer's law is obeyed in the working concentration range of 2.5-35 μg/mL with apparent molar absorptivity of 1.015×104 L/mol cm and Sandell's sensitivity of 0.001 μg/cm2/0.001 absorbance unit. The limits of detection and quantitation for the proposed method are 0.175 and 0.583μg/mL, respectively. The effect of common excipients used as additives has been studied in the determination of cefixime. The proposed method has been successfully applied for the determina- tion of cefixime in pharmaceutical formulations. The results obtained by the proposed method were statistically compared with the reference method using t and F values and found no significant difference between the two methods.
文摘The purpose of the investigation is the study of the physico-chemical properties and electro-catalytic characteristics of the Nafion and MF-4SK membranes with the author’s nanoparticles (A. Revina, 2008) incorporated into the perfluoro- sulphonated cationic membranes. An important advance in the creation of new nano-composite materials with poly-functional activity is the inclusion of nanoparticles of various metals (Pd, Pt, Ag) in these membranes. Polymer ion exchange membranes represent widely applicable materials in various areas of modern nanotechnologies. The obtained nanocomposites on the base of included nanoparticles have the perspective properties and polyfunctional activity for the applications.
文摘The Spent loaded-Pd cordierite honeycomb ceramic automotive catalytic converters,which were roasted to remove the deposit charcoal and other organic compounds,and were milled less then 100 mesh were reduced by HCOOH,which PdO was reduced to Pd and then the Pd was selectively leached with HCl-NaClO3.Palladium was determined by DDO spectrophotometry.In this paper,the determined results of several leaching methods were compared.The key factors which affected the Pd leaching by the system of HCl-NaClO3 were discussed and the optimal leaching conditions were proposed.The results indicated the Pd in automotive catalysts can be quantitatively analyzed by DDO spectrophotometry with HCl-NaClO3 for Pd leaching and at the same time the palladium of Pd-catalysts can be quantitatively determined.
文摘研究了在聚乙二醇 PAR 硫酸铵体系中萃取光度法测定钯的条件.在pH7.40的EDTA NaOH介质中,Pd(II) PAR被萃取到聚乙二醇相,最大吸收波长为525nm,摩尔吸光系数为3.71×104L·mol-1·cm-1,钯含量在0~26.4μg/10.0mL范围内符合比耳定律,检出限为0.029μg/10.0mL.方法用于碳钯催化剂和矿样中钯分离测定,结果满意.