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A new PVC membrane electrode for the determination of phenylephrine hydrochloride based on the formation of an ionassociation complex of phenylephrine hydrochloride with the phosphotungstate counter anion as an electroactive material dispersed in a PVC matrix is described. The sensor shows a fast, stable, near-Nernstian response for 1.0 × 10?5 to 1.0 × 10?1 M phenylephrine hydrochloride at 25 °C over the pH range of 3.5–8.0 with a cationic slope of 58.1 ± 0.6 mV decade?1. The electrode was successfully used for potentiometric determination of phenylephrine hydrochloride in some pharmaceutical drugs.  相似文献   
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5-Aryl-6-(alkyl- or aryl-amino)-1,3-dimethylfuro [2,3-d]pyrimidine derivatives were obtained by in situ reaction alkyl or aryl isocyanides and pyridinecarbaldehyde derivatives in the presence of 1,3-dimethylbarbituric acid in dichloromethane without any prior activation or modifications.  相似文献   
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In this article, we consider a class of nonlinear functional integral equations which has rather general form and contains a lot of particular cases such as functional equations and nonlinear integral equations of Volterra type. We use a combination of a fixed point method and cubic semiorthogonal B‐spline scaling functions to solve the integral equation numerically. We provide an error analysis for the method which shows that the approximate solution converges to the exact solution. Some numerical results for several test problems are given to confirm the accuracy and the ease of implementation of the method. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 699–722, 2014  相似文献   
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A series of α‐aminophosphonates were synthesized through one‐pot condensation of aryl aldehydes, aryl amines and diethyl phosphite in the absence of any catalyst and organic solvents. All the synthesized α‐aminophosphonates were characterized by spectral and elemental analysis and in the case of compound 4j by X‐ray crystallography. Some of these new α‐aminophosphonate derivatives were found to have cytotoxic activity on the cancer cell line DU145 in vitro by the MTT method.  相似文献   
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A novel magnetic acidic catalyst comprising Preyssler (H14[NaP5W30O110]) heteropoly acid support‐ed on silica coated nickel ferrite nanoparticles (NiFe2O4@SiO2) was prepared. The catalyst was character...  相似文献   
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