1. Graduate Research Assistant, Dept. of Material Science and Engineering, Boise State Univ., Boise, ID 83725.
2. Assistant Professor, Dept. of Civil Engineering, Boise State Univ., Boise, ID 83725 (corresponding author).
3. NIST Fellow, Applied Chemicals and Materials Division, National Institute of Standards and Technology, 325 Broadway MS 647, Boulder, CO 80305.