| Being far-from equilibrium by keeping their open, some systems could form to all types of spatiotemporal orderly structures (Chemical Oscillation, Chemical Chaos, Chemical Wave, Turing Pattern, etc.) by means of the nonlinear process. Actually, all these nonlinear chemical phenomena are very common in our daily life, for example, the shape of flowers or leaves, butterfly’s wings, the pattern in animal’s hair, cataphracted or strip clouds, amino acid sequences and so on. Recently, chemical oscillation has evolved to be one of the most extensively studied nonlinear systems since chemical oscillation is closely related to many disciplines like physics or biology. Therefore,the research on chemical oscillating theory and application will efficiently promote the progress in nonlinear dynamics.This paper reports a novel B-R chemical oscillator:H2SO4-[Ni(TIM)](ClO4)2-KIO3-oxaloacetic acid-H2O2, and manage to determine the antioxidant quantitatively and identify two isomers qualitatively by utilizing another B-R oscillator (H2SO4-[NiL](ClO4)2-KIO3-malonic acid -H2O2). The tetraaza-macrocyclic nickel(Ⅱ) complex [Ni(TIM)](C104)2 catalyzes this novel B-R oscillator with oxaloacetic acid as the substrate, where TIM in the ligand is 2,3,9,10-tetramethyl-1,4,8, 11-tetraazacyclotetradeca-1,3,8,10-tetraene. As we know, the structure of tetraaza-macrocyclic metal complex is similar to porphyrin ring of enzyme metal in biology cells, and oxaloacetic acid which is the intermediates of tricarboxylic acid cycle. Thereby, this new B-R oscillator have important implications for simulation of chemical oscillation to biological systems. Besides, the application of B-R oscillator in analysis field has been successfully expanded by this quantitative or qualitative accomplishment in analytical measurement.The summary in the first part put forward the concept of nonlinear chemistry, introduced the typical nonlinear chemical phenomena and gave an outline to the evolution of nonlinear chemical kinetics, including reaction conditions, reaction mechanisms or research progress.The second chapter designed a novel B-R chemical oscillator: H2SO4-[Ni(TIM)](ClO4)2-KIO3-oxaloacetic acid-H2O2, where TIM in the ligand is 2, 3,9,10-tetramethyl-1,4,8,11-tetraazacyclotetradeca-1,3,8,10-tetraene. The catalyst [Ni(TIM)] (ClO4)2 was synthesized according to the literature and was identified by IR and elemental analysis. The influences of initial concentration of reactants and temperature on the oscillator were observed by control variable method and probable mechanisms were proposed on the basis of the relevant references and mechanism model. In addition, three-electrodes method was applied to monitor the changes of electrode potential and the relationship between the potential of iodine electrode and iodine concentration was surveyed in this way.In chapter three, we quantitatively determined the chlorogenic acid (CA) by using another B-R chemical oscillator:H2SO4-[NiL](ClO4)2-KIO3-malonic acid-H2O2. The ligand L in the complex is 5,7,7,12,14,14-hexamethyl-1,4,8, 11-tetraazacyclotetradeca-4,11-diene. The catalyst [NiL](ClO4)2 was synthesized according to the literature and was identified by IR and elemental analysis. The experimental results have shown that addition of CA into the B-R oscillator could quench and then successfully regenerate the oscillations. In order to probe into the perturbation effect of CA, we defined a parameter:inhibition time (tin) which relies on the concentration of CA added, an calibration curve was thus established to detect the CA quantitatively. It’s found that the relationship between inhibition time (tin) and CA concentration is linear regression over the range 3.0×10-7-6.0×10-6 mol/L, and a polynomial regression was obtained over the range 6.0×10-6-3.0×10-5 mol/L. At the same time, we investigated the impact factors and the optimal concentrations on measurement of CA. Finally, the probable mechanism was proposed based on the cyclic voltammetry experiments and FCA model.We qualitatively identified two isomers, α-ketoglutaric acid (α-KA) and β-ketoglutaric acid (β-KA), by employing a B-R oscillator (H2SO4-[NiL](ClO4)2-KIO3-malonic acid-H2O2) in the last part. The repetition experiments proved that these two isomers could have markedly different perturbation effects on a [NiL]2+-catalyzed BR oscillator, so a new method could be expected to exploit this behavior to identify α-KA and β-KA. The concentrations of these two isomers that can be identified lie over the range between 5.0 × 10-6-2.5 × 10-3 mol/L. Furthermore, a reaction mechanism based on several experiments (like cyclic voltammetry, GC-MS, IR or haloform reaction) and FCA model has been proposed. |
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