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Title: Studies on microwave propagation properties of some biological tissues
Researcher: Kumar, Sanjeev
Guide(s): Adeel, Ahmad
Bellubbi, B S
Keywords: Physics
Upload Date: 24-Aug-2012
University: Jawaharlal Nehru Technological University
Completed Date: December 2011
Abstract: Microwaves interact with materials based on their electrical properties. Metals are good electrical conductors and good reflectors of microwave. They are not heated by microwave. Materials such as dielectrics come under electrical insulators and are good absorber and transmitter of microwave. Heat is generated in the dielectric (vegetables) primarily through absorption of microwave and the absorption, and hence the dielectric properties, depends on microwave frequency, composition of vegetables, product temperature, physical state of water in the vegetable, and product density. Absorption characteristics of a food can be changed significantly by altering the above factors. Microwave heating is mostly dielectric in nature and involves the rotation of dipolar molecules. The dielectric properties of vegetables are characteristics of the materials determining the interaction of electromagnetic energy with the materials. The dielectric properties such as dielectric constant and the dielectric loss factor play a major role in microwave heating. The capability of vegetable to store electric-field energy is dielectric constant. The dielectric loss factor measures the ability of vegetable material to dissipate electrical energy as heat. Therefore, the amount of dipolar molecules significantly affects the heating. When the dipolar are not evenly distributed in the material (vegetables), then uneven heating can be expected. Dielectric properties for some of the common vegetables at microwave frequency using von-Hippel technique are presented in the present investigation. There are many techniques developed for measuring the complex permittivity and permeability and each technique is limited to specific frequencies, materials, applications etc. by its own constraint. The limitation of this von-Hippel technique is, to prepare the samples of the dimension of the waveguide such that it has to fit exactly into it without air gap.
Pagination: 163p.
Appears in Departments:Faculty of Physics

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01_title.pdfAttached File131.64 kBAdobe PDFView/Open
02_dedication.pdf167.27 kBAdobe PDFView/Open
03_certificate.pdf138.51 kBAdobe PDFView/Open
04_declaration.pdf141.23 kBAdobe PDFView/Open
05_acknowledgements.pdf126.49 kBAdobe PDFView/Open
06_abstract.pdf122.24 kBAdobe PDFView/Open
07_outline.pdf148.09 kBAdobe PDFView/Open
08_table of contents.pdf175.9 kBAdobe PDFView/Open
09_list of figures.pdf258.05 kBAdobe PDFView/Open
10_list of tables.pdf178.02 kBAdobe PDFView/Open
11_list of symbols.pdf254.42 kBAdobe PDFView/Open
12_list of publications.pdf155.47 kBAdobe PDFView/Open
13_chapter 1.pdf1.28 MBAdobe PDFView/Open
14_chapter 2.pdf831.47 kBAdobe PDFView/Open
15_chapter 3.pdf976.5 kBAdobe PDFView/Open
16_chapter 4.pdf670.35 kBAdobe PDFView/Open
17_chapter 5.pdf180.81 kBAdobe PDFView/Open
18_references.pdf371.78 kBAdobe PDFView/Open
19_annuxaries.pdf3.31 MBAdobe PDFView/Open

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