Mformation about a material can be gathered from its interaction with electromagnetic waves. The information may be stored in the amplitude, the phase, the polarisation, the angular distribution of energy transportation or the spectral characteristics. When re trieved from the wave, certain material properties may thus be determined indirectly. Compared on the one hand to direct material analysis, an indirect method requires calibration and is prone to interference from undesired sources. On the other hand, however, it permits the determination of features inaccessible by direct methods, such as non-destructive material interrogation, high measurement speed, or deep penetration depth. However, being a physical method, the use of electromagnetic waves is still handicapped by the lack of acceptance by many chemists, who are used to applying direct approaches. Historically, the first application of electromagnetic wave interaction with mat ter involved measurement of amplitude changes at a single frequency caused by material properties, and it is still used today by some systems. This approach was soon supplemented by single frequency phase measurements, in order to avoid distortions through amplitude instabilities or parasitic reflections. Such single pa rameter measurements of course require dependence only on one variable in the measured process and sufficient stability of all other ancillary conditions. If that is not the case, the single parameter measurement fails.

The first book to address all theoretical and practical aspects of electromagnetic wave interaction with water and moist materials, this unique book features 29 full-length, peer-reviewed papers prepared by 69 of the world's experts in aquametry for a key Workshop held in conjunction with the IEEE MTT-S International Microwave Symposium in Atlanta, Georgia, 1993. Collectively, the papers illustrate the physical background of microwave techniques used for moisture content determination, present stimulating examples of applications of microwaves for nondestructive and accurate measurements, and demonstrate successful implementation of techniques in a variety of industries.

This collection of 23 contributions reviews the most common instruments for measuring food quality both on the processing line and in the laboratory. Each chapter describes an instrument's underlying principles with emphasis on aspects relevant to food applications, identifies the significance of the variables measured, and assesses the accuracy of the technique for specific food groups. The second edition adds eight chapters. Annotation copyrighted by Book News Inc., Portland, OR.

"Integrates principles of electromagnetics, dielectrics, heat and moisture transfer, packaging, solid mechanics, fluid flow, food chemistry, and microbiology to provide a comprehensive overview of microwave processing in a single accessible source."

Interactions of electromagnetic fields with materials at high frequencies have given rise to a vast array of practical applications in industry, science, medicine, and consumer markets. Applicators or probes, which are the front end of these systems, provide the field that interacts with the material. This book takes an integrated approach to the area of high frequency applicators and probes for material interactions, providing a toolkit for those who design these devices. Particular attention is given to real-world applications and the latest developments in the area. Mathematical methods are provided as design tools, and are often simplified via curve-fitting techniques that are particularly usable by handheld calculators. Useful equations and numerically solved examples, using situations encountered in practice, are supplied. Above all, this volume is a comprehensive and useful reference where the reader can find design rules and principles of high frequency applicators and probes for material processing and sensing applications. Electronic and electrical R&D engineers, physicists, university professors and students will all find this book a valuable reference. Mehrdad Mehdizadeh is with the DuPont Company, Engineering Research & Technology Division in Wilmington, Delaware. His areas of expertise include high frequency hardware and electromagnetic methods of processing, sensing, and characterization of materials. His work and innovation in industrial, scientific, and medical applications of radio frequency and microwaves has resulted in 19 US patents and a number of publications. He earned his Ph.D. and M.S. from Marquette University (1983, 1980), and a B.S. from Sharif University of Technology (1977), all in electrical engineering. Dr. Mehdizadeh is a Senior Member of the Institute of Electrical and Electronic Engineers (IEEE ), Sigma Xi (Scientific Research Society), the International Microwave Power Institute (IMPI ), and a voting member of IEEE Standard Association. - Books in this area are usually theoretical; this book provides practical information for those who actually intend to design a system - Features real world and numerically solved examples, and curve-fitted simple equations to replace complex equations provided in typical texts - Author is a voting member of IEEE Standards Association

The book covers the following areas: microwave measurement.

Handbook of Microwave Technology