Haşhaş Tohumunun Dielektrik Özellikleri

Year 2005, Volume: 11 Issue: 01, 104 - 109, 01.01.2005

Kâmil Saçılık Ahmet Çolak

https://doi.org/10.1501/Tarimbil_0000000498

Abstract

Haşhaş tohumunun dielekriksel özellikleri; %6.12-22.47 k.b. kuru baz nem, 541.99-626.37 kg/m3 hacim ağırlığı ve 50 kHz-10 MHz frekans aralığında paralel plakalı kondansatör tohum kutusu yardımıyla belirlenmiştir. Dielektrik sabiti, kayıp faktörü, kayıp tanjantı ve iletkenlik değerleri, nem, hacim ağırlığı ve frekanstan büyük ölçüde etkilenmiştir. Tohum nemi, haşhaşın dilektriksel özelliklerini etkileyen en önemli parametre olmuştur. Dielektrik sabiti ve kayıp faktörü, tohumun nemi ve hacim ağırlığıyla artarken uygulanan frekansla azalma göstermiştir. Dielektirik katsayısının uygulanan frekansa bağlı değişimi, kayıp faktörü ve kayıp tanjantına gore daha düzenli olmuştur. İletkenlik değerleri, artan frekanstan ziyade artan nem içeriğiyle daha hızlı bir artış göstermiştir. bir değişim göstermiştir. Ayrıca her iki modelin, çalışma aralığı içerisinde haşhaş tohumunun dielektrik katsayısı ve kayıp faktörünü yeterince tahmin edebildiği görülmüştür

Keywords

Dielektrik sabiti, kayıp faktörü, kayıp tanjant, iletkenlik, haşhaş tohumu

Dielectric Properties of Opium Poppy Seed

Abstract

The dielectric properties of poppy seed were determined over the frequency range from 50 kHz to 10 MHz at moisture content in a range of 6.12-22.47% dry basis d.b. with bulk density changing between 541.99 and 626.37 kg/m3 using parallel-plate capacitor sample holder. The dielectric constant, loss factor, loss tangent and the a.c. conductivity was greatly influenced by the moisture content, bulk density and frequency. The moisture content was the most significant factor affecting the dielectric properties of poppy seed. The dielectric constant and loss factor increased with an increase in moisture content and bulk density and with a decrease in frequency. The dependence of the loss factor and loss tangent on frequency was less regular than that of the dielectric constant. The a.c. conductivity was observed to increase more rapidly with increasing moisture contents than with increasing frequencies. Also, two models have been shown to estimate adequately the dielectric constant and loss factor of poppy seed within the investigated moisture content, bulk density and frequency range

Keywords

Dielectric constant, loss factor, loss tangent, conductivity, poppy seed

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