Role of heterogeneous reactions in generating chaos and noise in oscillatory chemical reactions
نویسندگان
چکیده
In view of the importance of noi se in physiology. information processing and fi nance, studi es on chaos and noi se have been undertaken. Detailed stud ies on the lal lowing osc illatory reactions have been undertaken: (i) thi ophenol + BrO,' + H2S0~, (ii ) fruClose + BrO,' + H2S04 + Ce 4 + , and (iii ) iodate + arsenitc, wh ich can serve as a model system for thi s purposc. Aperiodic oscil lations have been observed in these systems. Analys is of phase plane plots yields complex allractors. which arc quite different fro m strange att ractor indicating the occu rrence of random noise. Power spectra also indiccltc chaos with a broad band not necessaril y the determini stic chaos. For the reactions (i) and (iii ), a mechani sm has been proposed in volving precipitation of C6HS-S-C6HS and iod ine, respecti ve ly: whil e in case of reaction (ii ). gasco us evolution of Br2 has been invoked. Experimental studies on sed imentatio n of C6HS-S-C6H, and Br2 evo lu tion confirm that sueh hctcrogeneous reactions play an important role in gcnerating noi sc in osci ll at ions.
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