1. Department of Chemical Engineering University of Michigan Ann Arbor MI 48109 USA
2. Carl Zeiss Microscopy Inc. Pleasanton CA 94588 USA
3. Carl Zeiss Microscopy GmbH Oberkochen 73447 Germany
4. Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education) Northeastern University Shenyang 110819 China
5. Department of Materials Science & Engineering University of Michigan Ann Arbor MI 48109 USA
6. Department of Materials Science and Engineering University of California Berkeley CA 94720 USA