Browsing by Author "Canning, Griffin"
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Item Automated Enrichment of Single-Walled Carbon Nanotubes with Optical Studies of Enriched Samples(2013-05-13) Canning, Griffin; Weisman, R. Bruce; Hafner, Jason H.; Kono, JunichiroThe design and performance of an instrument is presented whose purpose is the extraction of samples highly enriched in one species of single-walled carbon nanotubes from density gradient ultracentrifugation. This instrument extracts high purity samples which are characterized by various optical studies. The samples are found to be enriched in just a few species of nanotubes, with the major limitation to enrichment being the separation, rather than extraction. The samples are then used in optical and microscopic studies which attempt to determine the first absorption coefficient (S1) of the (6,5) species of nanotube. Initial experiments give a value of 9.2 ± 2.6 cm2 C atom-1. Future work is proposed to improve upon the experiment in an attempt to reduce possible errorsItem High Precision Fractionator for use with Density Gradient Ultracentrifugation(American Chemical Society, 2014) Kadria-Vili, Yara; Canning, Griffin; Bachilo, Sergei M.; Weisman, R. Bruce; Richard E. Smalley Institute for Nanoscale Science and TechnologyThe recent application of density gradient ultracentrifugation (DGU) for structural sorting of single-walled carbon nanotube samples has created a need for highly selective extraction of closely spaced layers formed in the centrifuged tube. We describe a novel computer-controlled device designed for this purpose. Through the use of fine needles, systematic needle motions, and slow flow rates, multiple sample layers can be aspirated under program control with minimal cross contamination between layers. The fractionator’s performance is illustrated with DGU-sorted samples of single-walled carbon nanotubes.