1. Temple University(1987).
2. University of New Mexico(1989).
3. University of New Mexico(1989).
4. The Johns Hopkins University(1989).
5. Lehigh University(1989).
6. EXXON(1990).
7. University of the Balearic Island, Palma, Spain(1991).
8. MASSE Lecture, Kansas State University(1992).
9. Wichita State University(1992).
10. Michigan State University(1992).
11. American Chemical Society Colloid Symposium, Toronto(1993).
12. McGill University, Montreal(1994).
13. Kent State University(1995).
14. Southern Illinois University(1995).
15. University of Kansas, Lawrence(1996).
16. 44th Midwest Solid State Conference, Lincoln, Nebraska(1996).
17. University of Missouri, Columbia(1997).
18. Michigan State University(1997).
19. 11th Conference of the European Colloid and Interface Society, Lunte
20. University of Wageningen, Netherlands(1997).
21. University of Groningen, Netherlands(1997).
22. Symposium on current Issues in Non-Equilibrium Mechanics and Materials, Bethlehem, Pennsylvania(1997).
23. University of Nevada, Las Vegas (1998).
24. APS March Meeting, Los Angeles (1998).
25. Dow Chemical Corporation, Freeport, Texas (1998).
26. NIST, Gaithersburg (2000).
27. India and Abroad: A Conference on Condensed Matter Physics, Calcutta, India (2001)

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