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Search Publications by: Jeffrey Simpson (Assoc)

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Displaying 26 - 39 of 39

Centrifugal Length Separation of Carbon Nanotubes

October 1, 2008
Author(s)
Jeffrey A. Fagan, Matthew Becker, Jae H. Chun, Barry J. Bauer, Jeffrey R. Simpson, Angela R. Hight Walker, Erik K. Hobbie
Separation of single wall carbon nanotubes (SWCNTs) by length via centrifugation in a high density medium, and the characterization of both the separated fractions and the centrifugation process are presented. Significant quantities of the separated SWCNTs

Optical Anisotropy of Semiconducting Single-Wall Carbon Nanotubes

January 1, 2007
Author(s)
Jeffrey Fagan, Erik K. Hobbie, Jeffrey R. Simpson, Lee J. Richter, Idan Mandelbaum, Vardhan Bajpai, Derek L. Ho, Barry J. Bauer, Angela HightWalker, Ryan Raffaelle
We measure the full optical anisotropy of individual semiconducting single-wall carbon nanotubes (SWNTs). Dispersion of aligned SWNTs in stretched polymer films is confirmed with small-angle scattering and near-infrared fluorescence spectroscopy. By

Comparative Measures of Single Wall Carbon Nanotube Dispersion

September 14, 2006
Author(s)
Jeffrey A. Fagan, Brian Landi, Idan Mandelbaum, Vardhan Bajpai, Barry J. Bauer, Kalman D. Migler, Jeffrey R. Simpson, Angela R. Hight Walker, Ryan Raffaelle, Erik K. Hobbie
Model polymer composites of DNA wrapped single-wall carbon nanotubes (SWNTs) dispersed in polyacrylic acid are used for a systematic comparison of the different metrologies currently used to evaluate SWNT dispersion. Application of a pH-controlled

Quantitative, Interactive Measurement of Tissue Engineering Scaffold Structure Using Immersive Visualization

January 1, 2006
Author(s)
Jeffrey Fagan, Erik K. Hobbie, Brian Landi, Idan Mandelbaum, Vardhan Bajpai, Barry J. Bauer, Kalman D. Migler, Jeffrey R. Simpson, Angela R. Hight Walker, Ryan Raffaelle
At NIST, we are using new approaches to better understand and quantify the structure of tissue engineering scaffolds. This approach uses immersive visualization (IV) and is inherently three dimensional, multivariate and interactive, providing real-time