Author
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Nelson, Stuart |
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Submitted to: The Right Wave Length Royal Melbourne Institute of Technology Newsletter
Publication Type: Review Article Publication Acceptance Date: 5/1/1997 Publication Date: N/A Citation: N/A Interpretive Summary: Interpretive summary not required for literature review, book chapter (unless reporting original research), book review, or oral presentation (where only the title or abstract is published). D152.1 Technical Abstract: Research involving the dielectric properties of materials has been conducted by the ARS-USDA for 50 yrs. Initial research dealt with drying grain and alfalfa by radio-frequency (RF) dielectric heating. It soon became evident that information was needed on the dielectric properties of the products being treated. A measurement technique was developed for reliable determination of the dielectric properties of grain over the frequency range from 1-50 MHz and the first data were published in 1953. The research expanded to include studies on radio-frequency and microwave dielectric heating for stored-grain insect control, seed treatment to improve germination and seedling emergence and to control seed-borne disease organisms, treatment of alfalfa to improve carotene retention, treatment of soybeans to improve nutritional value, and treatment of pecans to retard deterioration in storage. Measurement techniques for determining gthe dielectric properties of materials were developed to cover the frequency range from audio frequencies through radio frequencies and into the microwave range. Dielectric properties data accumulated through the years on these various projects have been summarized and made available for use by researchers, instrument manufacturers, and design engineers. The RF and microwave lab moved to Athens GA in 1976, where dielectric properties research continued on fruits, vegetables, and pecans, and on using the dielectric properties of grain for moisture measurement. Current emphasis of the research is on using RF and microwave measurements for determination of moisture content in grain for on-line applications, where continuous monitoring of moisture content is important in preserving the quality of grain and in improving the quality of products manufactured from them. |
