Shilov constant

Here, Tq is the time required for the formation of the constant concentration profile of the sorbate (it is called the loss of protecting time) and K is the protecting time coefficient (the Shilov constant) indicating the protecting time of a layer of unit length. 

Lichtenfeld, H. Knapochinsky, L. Sonntag, H. Shilov, V. (1995) Fast coagulation of nearby spherical ferric oxide particles. Part I. Formation and decomposition of aggregates experimental estimation of velodty constants. Colloids Surfaces A. 104 313... 

Shilov et al studied the rate of oxidation of formate ions in phosphate and carbonate buffers, and showed that the reaction with molecular chlorine is negligible in solutions of pH > 6. At 20 °C the rate of reaction with hypochlorous acid is constant in the range pH 5.5-7, then it decreases with increase of pH, and becomes negligible at pH 13. The kinetics are second-order with respect to hypochlorous acid, and first with respect to formate ions. In alkaline solution hydroxide ion catalysis is apparent viz. 

The last equation demonstrates that the starting point for the solution of the problem is the calculation of ci(double layer (this makes low-frequency dielectric dispersion [LFDD] measurements a most valuable electrokinetic technique). Probably, the first theoretical treatment is the one due to Schwarz [61], who considered only surface diffusion of counterions (it is the so-called surface diffusion model). In fact, the model is inconsistent with any explanation of dielectric dispersion based on double-layer polarization. The generalization of the theory of diffuse atmosphere polarization to the case of alternating external fields and its application to the explanation of LFDD were first achieved by Dukhin and Shilov [20]. A full numerical approach to the LFDD in suspensions is due to DeLacey and White [60], and comparison with this numerical model allowed to show that the thin double-layer approximations [20,62,63] worked reasonably well in a wider than expected range of values of both and ku [64]. Figure 3.12 is an example of the calculation of As. From this it will be clear that (i) at low frequencies As can be very high and (ii) the relaxation of the dielectric constant takes place in the few-kHz frequency range, in accordance with Equations (3.56) and (3.57). 

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