By introducing periodic switching signal associated with illumination to the Originator,a switched mathematical model has been established.The bifurcation sets are derived based on the characteristics of the equilibri...By introducing periodic switching signal associated with illumination to the Originator,a switched mathematical model has been established.The bifurcation sets are derived based on the characteristics of the equilibrium points.Two types of periodic oscillation,such as 2T-focus/cycle periodic switching and 2T-focus/focus periodic switching,have been observed,the mechanism of which is presented through the switching relationship.The distribution of eigenvalues related to the equilibrium points determined by two subsystems is discussed to interpret oscillation-increasing and oscillation-decreasing cascades of the periodic oscillations.Furthermore,the invariant subspaces of the equilibrium point are investigated to reveal the mechanism of dynamical phenomena in the periodic switching.展开更多
A novel kinetic method for determination of uric acid in human serum by means of an uncatalyzed BZ system consisting of potassium bromate and p-hydroxybenzaldehyde （p-HBA） in sulfuric acid medium was proposed, in wh...A novel kinetic method for determination of uric acid in human serum by means of an uncatalyzed BZ system consisting of potassium bromate and p-hydroxybenzaldehyde （p-HBA） in sulfuric acid medium was proposed, in which the analyte perturbation to the system was recorded close to the bifurcation point. The potential change was directly proportional to the logarithm of concentration of uric acid in the range of 3.73 × 10 8--7.48 × 10-4 mol.L-1 （r=0.9983） with a detection limit of 7.45 × 10-9mol.L-I and a recovery from 98.9% to 101.1%. A comparison between the proposed technique and other methods indicated that results obtained were in agreement with those in clinical detection. In addition, the possible mechanism of action of uric acid on the uncatalyzed BZ reaction was also discussed briefly.展开更多
The BZ reaction in continuous-flow stirred tank reactor (CSTR) is selected, and the chaotic time series in low CSTR flow rates have been achieved. The power spectrum method (PSM) from physics and mathematics is introd...The BZ reaction in continuous-flow stirred tank reactor (CSTR) is selected, and the chaotic time series in low CSTR flow rates have been achieved. The power spectrum method (PSM) from physics and mathematics is introduced to compute the time delay %T%, the embedded dimension %m% so as to reconstruct the state space of the chaotic BZ reaction system by the time delayed coordinates. Further analysis and characterizations on the reconstructed chaotic attractor show that the results are in agreement with the references. It indicates that PSM is faster, simpler and reliable for processing the chaotic chemical system.展开更多
The central object of this work is to explore a method, which can be used toget information of other dynamic variables from the dependent time behaviors of any onedynamic variable in complex systems. The embedding pha...The central object of this work is to explore a method, which can be used toget information of other dynamic variables from the dependent time behaviors of any onedynamic variable in complex systems. The embedding phase patterns of o-NH2C4COOHBZ reaction systems were made based on embedding theorem and the experimental dataof concentration of bromine ion received by computer. A saturated embedding dimensionm≥8 has been shown, and a related BZ reaction mechanics with 10 chemical speciesas dyndric variables was presented and resolved by Gear algorithm. The concentrationswith time of Br- ,Mn3+, HBrO2, HOBr and BrO2, were simulated.展开更多
The oscillations of P-H2NC6H4COOH-KBrO3- H2SO4 system are studied. The dual-frequency oscillations are found in this system. Furthermore, the influences of initial reaction conditions (concentrations of reactans and t...The oscillations of P-H2NC6H4COOH-KBrO3- H2SO4 system are studied. The dual-frequency oscillations are found in this system. Furthermore, the influences of initial reaction conditions (concentrations of reactans and temperature) metal-ion catalysts and several additives on oscillating behaviors are concluded. These experimental phenomena suggested that the dual-frequency oscillations are controlled by two types of mechanism,one is bromide-ion controlling to the lower frequency oscillations, the other is non-brominde ion controlling to the higher ones, in which the substrate radicals play an important role.Moreover, these mechainsms are competing in the reaction system when the situation is fit for each one. Some interpretations about this are approached from the analysis of the composion of substrates and the viriation of potential during the reaction.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 20976075 and 10972091)College Graduate Student Scientific Research Innovation Foundation of Jiangsu,China (Grant No. CXLX12-0619)
文摘By introducing periodic switching signal associated with illumination to the Originator,a switched mathematical model has been established.The bifurcation sets are derived based on the characteristics of the equilibrium points.Two types of periodic oscillation,such as 2T-focus/cycle periodic switching and 2T-focus/focus periodic switching,have been observed,the mechanism of which is presented through the switching relationship.The distribution of eigenvalues related to the equilibrium points determined by two subsystems is discussed to interpret oscillation-increasing and oscillation-decreasing cascades of the periodic oscillations.Furthermore,the invariant subspaces of the equilibrium point are investigated to reveal the mechanism of dynamical phenomena in the periodic switching.
基金This work was supported in part by the Project of International Cooperation between China and Ukraine （No. 043-05）, the National Natural Science Foundation of China （No. 20873101）, the Natural Science Foundation of Gansu （No. 1010RJZA015） and the project LKQN-08-9 of Northwest Normal University, China.
文摘A novel kinetic method for determination of uric acid in human serum by means of an uncatalyzed BZ system consisting of potassium bromate and p-hydroxybenzaldehyde （p-HBA） in sulfuric acid medium was proposed, in which the analyte perturbation to the system was recorded close to the bifurcation point. The potential change was directly proportional to the logarithm of concentration of uric acid in the range of 3.73 × 10 8--7.48 × 10-4 mol.L-1 （r=0.9983） with a detection limit of 7.45 × 10-9mol.L-I and a recovery from 98.9% to 101.1%. A comparison between the proposed technique and other methods indicated that results obtained were in agreement with those in clinical detection. In addition, the possible mechanism of action of uric acid on the uncatalyzed BZ reaction was also discussed briefly.
文摘The BZ reaction in continuous-flow stirred tank reactor (CSTR) is selected, and the chaotic time series in low CSTR flow rates have been achieved. The power spectrum method (PSM) from physics and mathematics is introduced to compute the time delay %T%, the embedded dimension %m% so as to reconstruct the state space of the chaotic BZ reaction system by the time delayed coordinates. Further analysis and characterizations on the reconstructed chaotic attractor show that the results are in agreement with the references. It indicates that PSM is faster, simpler and reliable for processing the chaotic chemical system.
文摘The central object of this work is to explore a method, which can be used toget information of other dynamic variables from the dependent time behaviors of any onedynamic variable in complex systems. The embedding phase patterns of o-NH2C4COOHBZ reaction systems were made based on embedding theorem and the experimental dataof concentration of bromine ion received by computer. A saturated embedding dimensionm≥8 has been shown, and a related BZ reaction mechanics with 10 chemical speciesas dyndric variables was presented and resolved by Gear algorithm. The concentrationswith time of Br- ,Mn3+, HBrO2, HOBr and BrO2, were simulated.
文摘The oscillations of P-H2NC6H4COOH-KBrO3- H2SO4 system are studied. The dual-frequency oscillations are found in this system. Furthermore, the influences of initial reaction conditions (concentrations of reactans and temperature) metal-ion catalysts and several additives on oscillating behaviors are concluded. These experimental phenomena suggested that the dual-frequency oscillations are controlled by two types of mechanism,one is bromide-ion controlling to the lower frequency oscillations, the other is non-brominde ion controlling to the higher ones, in which the substrate radicals play an important role.Moreover, these mechainsms are competing in the reaction system when the situation is fit for each one. Some interpretations about this are approached from the analysis of the composion of substrates and the viriation of potential during the reaction.
