The Applications Of Oscillating Chemical Reactions In Analytical Determination

Part I Theoretical and experimental development of oscillating chemical reactions and their applications in analytical determinationOscillating chemical reactions have been the focus of much research in the area of theoretical and experimental chemical kinetics in recent years. The major task is to discover new oscillating systems, investigate the mechanisms of these reactions and explore the relationship between oscillating chemical reactions and the living organisms. In this section, we described the theoretical and experimental development of these reactions. The mechanisms of these reactions and their applications in analytical determination were also discussed in brief. Finally, we mentioned the importance of these reactions in the field of chemistry, biochemistry and engineering.Part II Kinetic determination of ascorbic acid by the BZ oscillating chemical systemA new analytical method for the determination of ascorbic acid by the perturbation caused by different amounts of ascorbic acid on the BZ oscillating chemical system involving the Ce(IV)-catalyzed reaction between potassium bromate and malonic acid in a acidic medium is proposed. The method relies on the linear relationship between the change in the oscillation amplitude of the chemical system and the concentration of ascorbic acid, which is in this work exposed for the first time. The calibration curve is linearly proportional to the concentration of ascorbic acid over the range 3.5x10-6-4.7x10-4M, with the regression coefficient is 0.9975. Two different methodologies were used to address the determination. Some aspects of the potential mechanism of action of ascorbic acid on the BZ oscillating chemical system are discussed in detail.Part III Determination of glutamic acid by an oscillating chemical reaction using the analyte pulse perturbation techniqueAn analytical method for the determination of glutamic acid by the sequential perturbation caused by different amounts of glutamic acid on the oscillating chemical system involving the Cu(II)-catalysed oscillating reaction between hydrogen peroxide and sodium thiocyanate in an alkaline medium is proposed. The method relies on the linear relationshipbetween the changes in the oscillation amplitude of the chemical system and the concentration of glutamic acid. The reaction is implemented in a continuous-flow stirred-tank reactor, and changes in the oscillation amplitude on each perturbation are proportional to the glutamic acid concentration. The use of the analyte pulse perturbation technique permits sequential determinations on the same oscillating system owing to the expeditiousness with which the steady state is regained after each perturbation. The dynamic range lies between 2.5x10-6 and 3.2x10-4M of glutamic acid, with the regression coefficient is 0.9987. The precision is excellent(less than 0.68% as relative standard deviation). Some aspects of the potential mechanism of action of glutamic acid on the oscillating system are discussed.Part IV The detection of the oscillatory domain of the Belousov-Zhabotinskii(BZ) oscillating chemical reaction and the Cu(II)-catalyzed oscillating chemical reactionThe oscillating chemical reactions have been the focus of much research in the area of theoretical and experimental chemical kinetics in recent years. Among these complex systems of chemical reactions, those that have received the most attention and most thoroughly investigated are the Belousov-Zhabotinskii(BZ) oscillating chemical reaction and the Cu(II)-catalyzed oscillating chemical reaction. For a chemical reaction to be the source of an auto-oscillating system, it must be far from equilibrium. That is to say, oscillating chemical reactions have their own oscillatory domain. In this section, we investigated the oscillatory domain of the Belousov-Zhabotinskii(BZ) oscillating chemical reaction and the Cu(ll)-catalyzed oscillating chemical reaction. Some factors which have effects on the oscillatory domain are discussed.