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Search Publications

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Displaying 1301 - 1325 of 1856

Relationship between dispersion metric and properties of PMMA/SWNT nanocomposites

June 13, 2007
Author(s)
Takashi Kashiwagi, Jeffrey Fagan, Jack F. Douglas, Kazuya Yamamoto, N. Alan Heckert, Stefan D. Leigh, Jan Obrzut, Fangming Du, Minfang Mu, Sheng Lin-Gibson, K Winey, R Haggenmueller
Particle spatial dispersion is a crucial characteristic of polymer composite materials and this property is recognized as especially important innanocomposite materials due to the general tendency of nanoparticles to aggregate under processing conditions

An Apparatus For Folding Yarns And Woven Fabrics Of Ballistic Fibers

June 4, 2007
Author(s)
Walter G. McDonough, Jae Hyun Kim, Nolan J. Brandenburg, William R. Blair, Gale A. Holmes
Folding of ballistic fibers comprising soft body armor may be a factor in the performance deterioration that has been observed in used soft body armor. To quantify the impact of this mechanism, an apparatus was designed and built to simulate the folding

Numerical Optimization of Matrix-Assisted Laser Desorption/Ionization Time-of- Flight Mass Spectrometry: Application to Synthetic Polymer Molecular Mass Distribution Measurement

May 26, 2007
Author(s)
William E. Wallace, Charles M. Guttman, Kathleen M. Flynn, Anthony J. Kearsley
A novel approach is described for the selection of optimal instrument parameters that yield a mass spectrum which best replicates the molecular mass distribution of a synthetic polymer. The application of implicit filtering algorithms is shown to be a

Polymer Viscoelasticity and Residual Stress Effects on Nanoimprint Lithography

May 24, 2007
Author(s)
Yifu Ding, Hyun Wook Ro, Jack F. Douglas, Ronald L. Jones, Daniel R. Hines, Alamgir Karim, Christopher L. Soles
We examine the influence of viscoelastic effects on the stability of nanoimprinted polymer films. The decay of features for polymers below the critical entanglement molecular mass at elevated temperatures is determined by simple surface tension and the

Measurement of Single Wall Nanotube Dispersion by Size Exclusion Chromatography

May 9, 2007
Author(s)
Barry J. Bauer, Matthew Becker, Vardhan Bajpai, Jeffrey A. Fagan, Erik K. Hobbie, Kalman D. Migler, Charles M. Guttman, William R. Blair
The dispersion of nanotubes in solution is necessary in order to achieve the goal of sorting and manipulating nanotubes by length and type and to then prepare high quality monodisperse samples. A necessary step is the proper characterization of the

Towards Industrial Scale Fabrication of Nanowire-Based Devices

April 11, 2007
Author(s)
Babak Nikoobakht
The key requirements for mass fabrication of nanodevices are directed positioning and alignment of nanoparticles (e.g., nanowires) with known registries on a large scale. Here, these issues are addressed in a high throughput and scalable approach for

Crystallization of Polyethylene Oxide Patterend by Nanoimprint Lithography

March 28, 2007
Author(s)
Brian C. Okerberg, Christopher L. Soles, Jack F. Douglas, Hyun Wook Ro, Alamgir Karim
The crystallization behavior of poly(ethylene oxide) (PEO) films patterned by nanoimprint lithography is studied. The imprinted PEO film consists of parallel lines, approximately 240 nm wide and 320 nm tall, on a 400 nm pitch with a residual layer of

Environment-Controlled Spin Coating to Orient Microdomains in Thin Block Copolymer Films

March 20, 2007
Author(s)
Sangcheol Kim, R M. Briber, Alamgir Karim, Ronald L. Jones, H C. Kim
We demonstrate a simple and fast methodology to control the orientation of cylindrical microdomains in thin block copolymer films using environment-controlled spin coating. During spinning, the preferential affinity of vapor atmosphere successfully directs

High Carrier Mobility Polythiophene Thin Films: Structure Determination by Experiment and Theory

March 19, 2007
Author(s)
Dean M. DeLongchamp, Regis J. Kline, Eric K. Lin, Daniel A. Fischer, Lee J. Richter, Leah A. Lucas, Martin Heeney, Iain McCulloch, John E. Northrup
We exploit the unprecedented crystallinity of poly(2,5-bis(3-alkylthiophene-2-yl)thieno[3,2-b]thiophenes) (pBTTTs) high performance semiconducting polymers to study structural detail within 25 nm thick films of a pBTTT with tetradecyl side chains (pBTTT

Numerical Path-Integration Technique for the Calculation of Transport Properties

March 13, 2007
Author(s)
E Kang, M Mansfield, Jack F. Douglas
We present a new technique for the computation of both the translational diffusivity and the intrinsic viscosity of macromolecules, and apply it here to approximately 1000 different protein structures. The computed translational diffusivities and intrinsic

Controlling Diffusion and Exchange in Layer-by-Layer Assemblies

March 6, 2007
Author(s)
Nicole Zacharia, Dean DeLongchamp, Miguel Modestino, P T. Hammond
Here we present a layer-by-layer (LbL) assembled device architecture that serves as a model heterostructure to study the atypical assembly that can result from the bottom-up combination of multiple multilayers of different compositions. Heterostructure

Effect of Photoacid Generator Concentration and Developer Strength on the Patterning Capabilities of a Model EUV Photoresist

February 25, 2007
Author(s)
Kwang-Woo Choi, Vivek Prabhu, Kristopher Lavery, Eric K. Lin, Wen-Li Wu, John T. Woodward IV, Michael Leeson, H Cao, Manish Chandhok, George Thompson
Current extreme ultraviolet (EUV) photoresist materials do not yet meet requirements on exposure-dose sensitivity, line-width roughness (LWR), and resolution. Fundamental studies are required to quantify the trade-offs in materials properties and

Evaluation of the 3D Compositional Fluctuation Effect on Line-Edge-Roughness

February 25, 2007
Author(s)
Shuhui Kang, Wen-Li Wu, B D. Vogt, Vivek Prabhu, Eric K. Lin, Karen Turnquest
Line-edge-roughness (LER) and the relationship to resist processing and materials design is a critical problem for sub-65 nm photolithography. In this work we investigate how chemical composition fluctuations (heterogeneity) produced by the reaction
Displaying 1301 - 1325 of 1856