1. Montgomery Blair High School, Silver Spring, Maryland 20901, USA
2. Polymers and Complex Fluids Group, Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
3. Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, USA
4. Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA