Kinetics fractal-like

Chapter 15 - It was shown, that the reesterification reaction without catalyst can be described by mean-field approximation, whereas introduction of catalyst (tetrabutoxytitanium) is defined by the appearance of its local fluctuations. This effect results to fractal-like kinetics of reesterification reaction. In this case reesterification reaction is considered as recombination reaction and treated within the framework of scaling approaches. Practical aspect of this study is obvious-homogeneous distribution of catalyst in reactive medium or its biased diffusion allows to decrease reaction duration approximately twofold. 

Fractal-Like Kinetics of Reesterification Reaction in Catalyst Presence... 

Let s consider the reasons of reesterification reaction fractal-like kinetics in TBT presence. This reaction can be described in general form as recombination reaction of reagents A and B [4] ... 

Let s note three important aspects followed from the model [4] application for description of reesterification reaction. At first as reesterification reactions with TBT and in it absence proceed in identical conditions, then from the comparison of figure 1 kinetic curves follows, that the reaction fractal-like behaviour in TBT presence is due to local fluctuations of catalyst distribution in reactive medium. Secondly the division of reaction duration into short and long... 

E. I. Newhouse and R. Kopelman, Fractal-like triplet-triplet annihilation kinetics in naphthalene-doped poly(methylmethacrylate), Chem. Phys. Lett. 143, 106-110(1988). 

The kinetic consequences that are associated with the time-dependency of the rate constant are delineated in Section 2.5 under the heading, coined by Kopelman [9,16], fractal-like kinetics. 

The general fractal relationship for the description of reaction in solutions kinetics looks like [87] ... 

Heterogeneous reaction kinetics in areas such as chemistry, biology, geology, solid-state physics, astrophysics and atmospheric science can be understood in terms of fractal kinetics. Recently, Rastogi et al. [42] performed an experiment to visualize the phenomenon in a solid-gas reaction. Mercurous chloride thin film was prepared on micro-slide and put in the iodine chamber. A white continuous interface was covered with yellow HgClI after 15 min (Fig. 13.17). The interface becomes percolation cluster type after 2 h. At the end of the reaction (after 72 h) red crystals are found embedded on the reaction interface. For the reaction to obey fractal-like kinetics, the reaction between thickness of the boundary layer at time t is complex. These authors have further observed an identical relation for the above reaction, where k° is some... 

Since the excited state was associated with the dissociation of CH3OH, the irradiation time-dependent excited resonance signal illustrated essentially the kinetics of photocatalyzed dissociation of CH3OH on rutile TiO2(H0). The integrated time-dependent excited resonance signal (Fig. 11.18b) could not be described by a single exponential model, while a fractal-like kinetic model (Eq. 11.7) [164, 165] stimulated the data well ... 

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