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تسجيل مستخدم جديدSimulation and Experimental Investigation of Cellular Material Breakage Using the Pulsed Electric Field Treatment
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We consider the simplified dielectric breakage model used for simulation of the kinetics of cellular material breakage under the pulsed electric field (PEF) treatment. The model is based on an effective media approximation, which includes equations with the same morphology parameters as in percolation theory. The probability of a whole cell breakage by the pulse with $t_{i}$ duration is estimated on the basis of electroporation theory. We account for the bridging effect resulting from the deviations of the local conductivity near the selected cell from the average effective media conductivity. The most important feature of the proposed model is the existence of the ``jamming behaviour occurring sometimes in experimental observations of the biological tissue breakage. The different transitions corresponding to the ``jamming steps are identified. The experimental results are obtained for thin apple slices treated with electric pulses at field strengths $E=0.2-2.2$ kV cm$^{-1}$, pulse durations $t_{i}=10-100$ $mu$s, pulse repetition times $t=10-100$ ms and the number of pulses $N=1-100000$. The model gives results consistent in general with the experimental observations. We discuss the correlation between the degree of cellular material destruction, field strength, time of PEF treatment and power consumption.
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