Etoricoxib selective sensor based on uracil-5,6-diamino-2-thio hydrochloride as neutral carrier for potentiometric analysis in pharmaceutical preparations
A construction and electrochemical behavior of novel potentiometric membrane sensor responsive to the etoricoxib was described. The sensor was based on the ion-pair complex of etoricoxib (ET) with Uracil-5,6-diamino-2-thio hydrochloride UDTH (ET-UDTH) as exchange sites in a PVC matrix with different plasticizers dibutylphthalate (DBP) (electrode B) tri-n-butylphosphate (TBP) (electrode C), and dioctylphthalate (DOP) (electrode A). The electrodes exhibited near-Nernstian response for ET-UDTH over the concentration range 0.051-40.042 mM. The electrode offered significant advantages including long lifetime (about 2 months), excellent stability and reproducibility, good response time (10-25 s), and wide pH working range (pH 5-12). Selectivity coefficients of ET related to a number of interfering cation and some organic compounds were investigated, and there were negligible interference caused by most of the investigated species. The direct determination of 0.5-10 mM of ET showed an average recovery of 99.03-101.75% and a mean relative standard deviation 0.40-1.88. The results were obtained by determination of ET in tablets using the proposed electrodes which were comparable favorably with those obtained by spectrophotometric method
PURE
Abstract Despite large public policy efforts over the past 30 years, a large minority of households remains consistently inadequately prepared for retirement. If policymakers want to address this shortcoming, public policy has to change from its current path. This paper suggests a system of mandatory private pensions funded by a minimum mandatory contribution of 3% of payroll. In addition, a number of institutional changes are suggested to reduce the costs and risks of individual accounts.
Thermodynamics on the Carbochlorination of Titanium-bearing Ores
The equilibrium compositions of the multi-component, multi-phase and multi-reaction system of carbochlorination of titanium-bearing ores are calculated with HSC, a computational chemistry software. The thermodynamic equilibrium calculation of the reaction system shows that a complete conversion of titanium-bearing ores is feasible at a temperature near 200oC. At temperatures ranging from 800 to 1600oC, the products of the reaction system are all in gaseous phase. Thermodynamic analysis accords with the industrial practice. The simulated results provide reasonable scientific basis for improving suitable technological conditions of the carbochlorination reduction.