1. Department of Mechanical Engineering, Materials Science and Engineering Program, Texas A&M University, College Station, TX 77843-3123 e-mail:
2. Materials Physics and Application Division, Los Alamos National Laboratory, Los Alamos, NM 87545
3. Department of Nuclear Engineering, Texas A&M University, College Station, TX 77843-3128
4. Department of Electrical Engineering, Texas A&M University, College Station, TX 77843-3128