Effect of Microwave Radiation on Tobacco (Nicotiana tabacum) Using VSWR Method

Abstract

The values of dielectric constant (ε'_p), dielectric loss (ε"_p), relaxation time ( _p) and conductivity ( _p) of the sample were measured for different packing densities at 9.85 GHz microwave frequency and different temperature (20⁰C, 35°C and 50⁰C). Complex permittivity of Tobacco leaves has been measured over the 9.85 GHz single High frequency range using X - band microwave bench. To measure the dielectric parameter by using Sample holder for pulverized sample. We have designed and fabricated the sample holder at Microwave Research Laboratory, NES, Science College, Nanded. The experimental and calculated values for dielectric constant ( ) and dielectric loss ( ) are found to be same at relative packing fractions δ_r   = 1. The above fact indicates that there is a fair agreement between calculated values of dielectric parameters and measured values of solid bulk. The co-relation formulae of Bottcher can be used to provide accurate estimates of ( ) and ( ) of powder materials at known bulk densities. The values of ( _p) obtained suggest that the dielectric loss factor ( _p) increases with the increase of bulk density of the material. The increase in conductivity with increase of packing fraction suggests that, at higher compaction the particles are more packed, and no micro-cracks developed in the samples. As packing fractions (δ_r) and temperature increases the moisture content of sample decreases linearly. The variations of ( _p), ( _p),  tanδ, and σ_p with relative packing fraction (δ_r), and temperature clearly indicates that, effect of density and temperature on the dielectric parameters. The result shows that large cohesion in the particles of Tobacco leaves powder under investigations.