Arc-synthesized single-walled carbon nanotubes have been purified through preparative electrophoresis in agarose gel and glass bead matrixes. Two major impurities were isolated: fluorescent carbon and short tubular carbon. Analysis of these two classes of impurities was done. The methods described may be readily extended to the separation of other water-soluble nanoparticles. The separated fluorescent carbon and short tubule carbon species promise to be interesting nanomaterials in their own right.

No abstract

Buckminsterfullerene (C60), the newly discovered spherical allotrope of carbon, has precipitated a flurry of recent research endeavors.1 A severe limitation to this research is the difficulty in producing gram quantities of Cm free of the higher molecular Company. W.A.S. thanks NASA and the American Vacuum Society for scholarships. We thank Dr. Nick Griffith of the

Methods for patterning metal thin films at the microscale and nanoscale by applying the patterns to metallic and polymeric materials for use in shape and deformation measurements in a scanning electron microsope (SEM) or other high magnification imaging system are described. In one approach, thin films of metallic materials (e.g., Au, Ag, Cu, and Cr) are applied to a variety of substrates. The coated samples are then placed into a reaction vessel, where the specimens are heated and exposed to a nitrogen atmosphere saturated with selected volatile chemicals. This process results in nano-scale remodeling of the metallic films, thereby affording high contrast random patterns with different morphologies. In a second approach, thin films of metallic materials, including gold and silver, also have been applied using a simplified UV photolithographic method requiring a minimum amount of laboratory preparation. Using selected substrates, both methods have been used successfully to transfer patterns onto polymeric and metallic materials ranging from 50-500 nanometers with chemical vapor rearrangement and 2 to 20 microns with UV photolithography, providing a pattern that can be used with digital image correlation to quantify both the surface profile and also surface deformations at reduced length scales.

No abstract

REPORT DOCUMENTATION PAGE om Iv 07408 '' c "of nfc,.t o-fti"u-lca tc 6.0c.ge I,, aý pronie A0d. n ttec trceto Reproduction in whole or in part is permitted for any purpose of the United States Government. This document has been approved for public release and sale; its distribution is unlimited.1 ABSTRACT (Maximum 200 words)Described are several solvents for the dissolution of fullerenes. The two best solvents found were 1,2-dichlorobenzene and 1-methylnaphthalene which dissolve C60 up to 24.6 and 33.2 mg mL-1, respectively. The solubility data was obtained gravimetrically. Precipitates were 0 -obtained when C6iO was treated with 1 ,3,5-trimethylbenzene or I ,2,4-trichlorobenzene. Scanning ____ electron micrographs and thermogravimetric analysis data were obtained on the precipitates and compared to the data obtained for pure C60. The efficacy of l,2-dichlorobenzene and 1-___ methylnaphthalene as 13 C NMR solvents for fullerene analysis was demonstrated as well as the ____ utility of 1 ,2-dichlorobenzene for the extraction of higher fullerenes from soot. 0) WI; SUBJECT TERMS NUMBER OF PAGES"ýN' Described are several solvents for the dissolution of fullerenes and the efficacy of 1,2-dichlorobenzene and 1-methylnaphthalene for obtaining fullerene 13C NMR spectra.

No abstract

No abstract