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In this study, numerically investigated effect of magnetic heat sources (residual and hysteresis) that can be useful in hyperthermia and their effects on cancerous tissue. The governing equations of continuty, momentum, concentration, energy and Arrhenius tissue destruction equation in the form of couplings are defined, solved and investigated in the finite-element COMSOL software. For blood flow inside the cancerous capillary, non-newtonian and temperature dependent model is used. The geometric model is simulated in three dimensions, including the capillary and cancerous tissue. Thermophysical properties of blood and tissue are also temperature dependent. Results indicated that the residual heat source plays a major role in increasing the temperature of the blood and tissue and can be ignored the effect of hysteresis heat source. The residual heat source has an inverse relation to the particle size and is ineffective in the particle size above 100 nm but hysteresis heat source is directly related to the size of the nanoparticles, and for particles with a size of 150 nm, it will result in a 1 degree increase in temperature for the tissue. The increase in blood temperature for 25 nm magnetic nanoparticles with the residual heat source can lead to the most destruction in cancerous tissue. Also, the viscosity of blood has an inverse relation with the concentration of magnetic nanoparticles in the capillary wall and blood temperature.

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Experiments were conducted to study the color change kinetics of green bell pepper during vacuum-assisted microwave (VAM) drying at three levels of microwave power (100, 200, and 300 W) and vacuum (200, 400, and 600 mmHg). The color change, measured by a tristimulus colorimeter, in VAM dried sample was found better with least browning at lower microwave power and higher vacuum level combinations. L^*, ΔE^* and H^* were fitted well to zero-order kinetic model, while a^*, b^*, C^* and BI^* followed a first-order kinetic model. All these color parameters were fitted to a quadratic equation as a function of microwave and vacuum level ratio. Both ΔE^* and BI^* increased with the increase in microwave power and decrease in vacuum level, whereas other color parameters decreased under the same condition of the process variables. The rate constant was assumed to have Arrhenius-type dependence on power density. The activation energy was calculated for color change kinetic parameters by using an exponential expression based on Arrhenius equation. The activation energy values were calculated and found within the range of 3.20-13.58 Wg^‒1, except for b^* (E_a = 26.708 Wg^‒1) and C^* value (E_a = 20.4105 Wg^‒1). The b^* and C^* values obtained were relatively higher and thus were more sensitive measures of color change, which must be taken care of during postharvest drying of green bell pepper for getting a quality product.