Roman Gr. Maev received his Ph.D. from the Physical Institute of the Russian Academy of Sciences in 1973 and his D.Sc. in acoustic microscopy from the Russian Academy of Sciences, Moscow, in 2002. From 1994 to 1997, he held a post as Director of the Acoustic Microscopy Center of the Russian Academy of Sciences, then established the Centre for Imaging Research and Advanced Material Characterization at the University of Windsor, Canada. He is currently a Full Faculty Professor at the Physics Department at the same University and since 2001 the Chairholder of the NSERC/DaimlerChrysler/Industrial Research Chair in Applied Solid State Physics and Material Characterization. Professor Maev's… research interests focus on the fundamentals of condensed matter, physical acoustics, ultrasonic imaging, and acoustic microscopy. He has published numerous books, more than 300 scientific papers, and holds twenty patents.Volf Leshchynsky received his Ph.D. from the Technical Physics Institute at the Russian Academy of Sciences, Moscow, in 1968, and his D.Sc. from the Institute of Metallurgy at the same University in 1989. He then held a chair as professor of the Metal Forming Institute, Poznan, Poland, and became Head of the Metal Forming Department at the East Ukrainian University. He is currently a visiting professor at the Physics Department of the University of Windsor, Canada, where he conducts research in new powder metallurgy, nanostructuring, and cold spray techniques. Dr. Leshchynsky's research interests include the fundamentals of nanotechnology and nanostructured materials, and the development and application of powder spraying and powder metallurgy. He is the author of more than 150 scientific papers and holds thirty patents.