| From the birth of the universe,chemical oscillations have existed in nature.There are many kinds of chemical oscillation systems,including Belousov-Zhabotinsky,Briggs-Rauscher and Bray-Liebhafsky systems.In chemical oscillation,the concentration of intermediate change periodically.Scientists use this characteristic to make chemical oscillation widely use in pharmaceutical chemistry,biology,physics and other fields.At the beginning of this paper,the background,mechanism and development of BZ and BR reaction systems were introduced.Secondly,because BZ and BR systems are related to non-linear chemistry,the knowledge of non-linear chemistry was also introduced in the first chapter.In the 2nd chapter,a new method for identifying aldehydes and ketones was introduced by BZ oscillation consisted of sulfuric acid,[CuL](ClO4)2,malic acid and sodium bromate.First,catalyst[CuL](ClO4)2 was prepared.IR and elemental analysis were used to identify it.Aldehydes and ketones were added into the system respectively.It was found that the addition of aldehyde made the potential of the system decrease.However,when ketone was added to the system,the system was not affected.Therefore,aldehydes and ketones can be successfully identi fied by the disturbance difference of aldehydes and ketones to the system.Moreover,we found that with the increase of aldehyde concentration,the potential of the system decreased more obviously.Aldehydes identified include acetaldehyde,propanal,butyraldehyde,valeraldehyde,3-methylbutyraldehyde and hexanal.Ketones identified include acetone,2-pentanone and 2-hexanone.Because of the difference in solubility,aldehydes and ketones identified have their own concentration ranges.The concentration of acetaldehyde ranged from 1.8 × 10-4 mol/L to 8 × 10-4 mol/L.The concentration of butyraldehyde ranged from 1.5 × 10-4 mol/L to 6 × 10-4 mol/L.The concentration of 3-methylbutvraldehyde ranged from 1 × 10-4 mol/L to 4 × 10-4 mol/L.The concentration of acetaldehyde and acetone ranged from 3 × 10-4 mol/L to 1.75 ×10-3 mol/L.The concentration of valeraldehyde and 2-pentanone ranged from 1 × 10-4 mol/L to 4 × 10-4 mol/L.The concentration of hexanal and hexanone ranged from 1 ×10-4 mol/L to 2 x 10-4 mol/L.Then,the products of aldehyde oxidation were confirmed by CV and GC-MS technology.The aldehydes were found to be oxidized to carboxylic acid compounds.The reaction disturbance mechanism was deduced according to the mechanism of FKN.In the 3rd chapter,determining the syringic acid by BR system is introduced.BR system consists of sulfuric acid,[NiL](ClO4)2,malonic acid,potassium iodate and hydrogen peroxide.The ligand "L" in the complex[NiL](ClO4)2 is 5,7,7,12,14,14-hexemethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene.First,catalyst[NiL](ClO4)2 was prepared.IR and elemental analysis were used to identify it.The syringic acid was added to the above system.It was found that the addition of syringic acid stopped and restored the oscillation.This period is expressed in tin.And it took longer time to restore the oscillation due to the increase of CSA.Then,by establishing the working curve of tin and the concentration of syringic acid,it is found that there is a linear relationship between tin and the concentration of syringic acid.The relationship was tin=5.03543E7*CsA-6.94517(R=0.99477,N=19).The concentration of syringic acid was over the range 2.50 × 10-7-1.00 × 10-5 mol/L.Therefore,we can use this relationship to determine syringic acid in the range of 2.50 × 10-7-1.00 ×10-5 mol/L.In addition,change in the concentration of the substances that made up the BR system would affect the reaction,so we have also explored the optimum concentration of the BR system.Finally,in order to explore the reaction mechanism,CV experiments were carried out and the perturbation mechanism of syringic acid was deduced based on NF and FCA.Finally,a new method for the determination of sinapic acid is introduced by BR system consisted of sulfuric acid,[NiL](ClO4)2,malonic acid,'potassium iodate and hydrogen peroxide.The addition of sinapic acid inhibited and restored the oscillation.The inhibition time was expressed by tin.And it took longer time to restore the oscillation due to the increase of CSA.The working curve between the concentration of sinapic acid and tin was established.When the concentration of sinapic acid was over the range 1.00 × 10-6-3.00×10-5 mol/L,there was a linear relationship between them.The relationship was tin=1.23247E7*CsA+19.21534(R=0.9947,N=15).Therefore,we can use this equation to determine sinapic acid.In addition,the optimum concentration of various substances on BR system was also explored.Finally,we carried out CV experiments and inferred the disturbance mechanism of sinapic acid based on NF and FCA. |
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