The Dielectric Properties of Worker Bee Homogenate in a High Frequency Electric Field

oleh: Leszek Szychta, Piotr Jankowski-Mihułowicz, Elżbieta Szychta, Krzysztof Olszewski, Grzegorz Putynkowski, Tadeusz Barczak, Piotr Wasilewski

Format: Article
Diterbitkan: MDPI AG 2022-12-01

Deskripsi

Biological tissues, including insect tissues, are among lossy dielectric materials. The permittivity properties of these materials are described by loss factor <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi>ε</mi><mrow><mo>″</mo></mrow></msup></mrow></semantics></math></inline-formula> and loss tangent tg<i>δ</i>. The dielectric properties of the worker honeybee body homogenate are tested in the range of high frequencies from 1 MHz to 6 GHz. The homogenate is produced by mixing whole worker honeybees and tested with an epsilometer from Compass Technology and a Copper Mountain Technologies vector circuit analyser VNA. Due to their consistency, the homogenate samples are placed inside polyurethane sachets. The measured permittivity relates to two components of a sample: homogenate and polyurethane. For five samples, two extremes were specified for the permittivity, loss factor <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi>ε</mi><mrow><mo>″</mo></mrow></msup></mrow></semantics></math></inline-formula>, and the loss tangent tg<i>δ</i>, for the frequency range 20 ÷ 80 MHz and 3 GHz. Four techniques of testing permittivity in biological tissues were used to determine the dielectric properties of the homogenate. A calculation model was developed featuring a minimum measurement error of the loss factor <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi>ε</mi><mrow><mo>″</mo></mrow></msup></mrow></semantics></math></inline-formula> and the loss tangent tg<i>δ</i>. The power absorbed per unit volume is described for the whole frequency range.