The diploma thesis deals with the study of the influence of moisture content of pedunculate oak (Quercus petraea) wood on its dielectric and dynamic mechanical properties. The research work was carried out on thin lamellas that were either dried to an absolutely dry state, equilibrated at a temperature of 20 °C and at different relative air humidities (33 %, 65 % and 85%), or steamed in a chamber with water saturated steam at 90 °C. First, we performed a test of dynamic mechanical properties with equipment for determining the frequency response to impulsive mechanical excitation in the transverse direction to the direction of wood fibers. Then we continued with testing the dielectric properties, which was performed at room temperature in the electromagnetic field frequency range from 79 kHz to 25.119 MHz. We found that as the moisture content of wood increases, its dynamic modulus of elasticity (E) decreases. As the moisture content of wood increases, the values of the detected acoustic parameters (R, ACE and RACE) also decrease, while the damping of mechanical vibrations (tanζ) increases. We found that as the moisture content of wood and the frequency of the electromagnetic field increase, its dielectric constant (ε) and loss factor (tanδ) increase. The only exception was wood that was exposed to steaming at a higher temperature, for which its moisture content decreased rapidly.
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