Three simple,specific,accurate and precise spectrophotometric methods are developed for simultaneous determination of amlodipine besylate(AM)and atenolol(AT)in tablets.The first method is dual wavelength spectrophotom...Three simple,specific,accurate and precise spectrophotometric methods are developed for simultaneous determination of amlodipine besylate(AM)and atenolol(AT)in tablets.The first method is dual wavelength spectrophotometry(DW).The second method is ratio subtraction(RS)which depends on subtraction of the plateau values from the ratio spectrum,coupled to first derivative of ratio spectra(1 DD).The third method applies bivariate calibration method using 210and 225nm as an optimum pair of wavelength for amlodipine and atenolol.The calibration curves are linear over the concentration range of 4~40μg·mL-1 for both drugs.The specificity of the developed methods is investigated by analyzing laboratory prepared mixtures of the two drugs and their combined dosage form.The two methods are validated as per ICH guidelines and can be applied for routine quality control testing.展开更多
An MMI double-wavelength optical power splitter for both 1.55μm and 1.3μm is presented in this paper. Analysis shows that it can divide power equally for both 1.55μ m and 1.3μm.
Experiments were conducted to investigate the degradation of 2,6-dinitro-p-cresol(DNPC)in the chlorine dioxide(ClO_(2))catalytic oxidation process.Pure aluminum oxide was used as the catalyst in this process.The degra...Experiments were conducted to investigate the degradation of 2,6-dinitro-p-cresol(DNPC)in the chlorine dioxide(ClO_(2))catalytic oxidation process.Pure aluminum oxide was used as the catalyst in this process.The degradation of DNPC by ClO_(2) using aluminum oxide as catalyst was systematically studied by varying the experimental parameters,such as pH values,catalyst dosage,the initial concentration of DNPC and ClO_(2),reaction time,etc.Under optimal condition(DNPC concentration 39 mg$L–1,ClO_(2) concentration 0.234 g$L–1,reaction time 15 min,catalyst dosage 4.7 g$L–1 and pH 4.32),almost complete degradation of DNPC can be achieved.The kinetic studies revealed that the ClO_(2) catalytic oxidation degradation of DNPC followed pseudo-first-order kinetics with respect to both ClO_(2) and DNPC concentration.The repetitive use of the catalyst was investigated along sequential feed-batch trials.The catalyst performed efficiently afterfive runs.In addition,a simple and convenient method for the determination of ClO_(2) in water was developed by using acid chrome black 7(MB 7)spectrophotometry in this paper.展开更多
文摘Three simple,specific,accurate and precise spectrophotometric methods are developed for simultaneous determination of amlodipine besylate(AM)and atenolol(AT)in tablets.The first method is dual wavelength spectrophotometry(DW).The second method is ratio subtraction(RS)which depends on subtraction of the plateau values from the ratio spectrum,coupled to first derivative of ratio spectra(1 DD).The third method applies bivariate calibration method using 210and 225nm as an optimum pair of wavelength for amlodipine and atenolol.The calibration curves are linear over the concentration range of 4~40μg·mL-1 for both drugs.The specificity of the developed methods is investigated by analyzing laboratory prepared mixtures of the two drugs and their combined dosage form.The two methods are validated as per ICH guidelines and can be applied for routine quality control testing.
文摘An MMI double-wavelength optical power splitter for both 1.55μm and 1.3μm is presented in this paper. Analysis shows that it can divide power equally for both 1.55μ m and 1.3μm.
基金financial support provided by the National Natural Science Foundation of China(Grant No.20977013).
文摘Experiments were conducted to investigate the degradation of 2,6-dinitro-p-cresol(DNPC)in the chlorine dioxide(ClO_(2))catalytic oxidation process.Pure aluminum oxide was used as the catalyst in this process.The degradation of DNPC by ClO_(2) using aluminum oxide as catalyst was systematically studied by varying the experimental parameters,such as pH values,catalyst dosage,the initial concentration of DNPC and ClO_(2),reaction time,etc.Under optimal condition(DNPC concentration 39 mg$L–1,ClO_(2) concentration 0.234 g$L–1,reaction time 15 min,catalyst dosage 4.7 g$L–1 and pH 4.32),almost complete degradation of DNPC can be achieved.The kinetic studies revealed that the ClO_(2) catalytic oxidation degradation of DNPC followed pseudo-first-order kinetics with respect to both ClO_(2) and DNPC concentration.The repetitive use of the catalyst was investigated along sequential feed-batch trials.The catalyst performed efficiently afterfive runs.In addition,a simple and convenient method for the determination of ClO_(2) in water was developed by using acid chrome black 7(MB 7)spectrophotometry in this paper.
