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Displaying 1326 - 1350 of 1856

FTIR measurements of compositional heterogeneities

February 25, 2007
Author(s)
Shuhui Kang, B D. Vogt, Wen-Li Wu, Vivek Prabhu, David L. VanderHart, Ashwin Rao, Eric K. Lin, Karen Turnquest
A general approach to characterize compositional heterogeneity in polymer thin films using Fourier transform infrared (FTIR) spectroscopy has been demonstrated Polymer films with varying degrees of heterogeneity were prepared using a model chemically

Identifying Materials Limits of Chemically Amplified Photoresists

February 25, 2007
Author(s)
Wen-Li Wu, Vivek Prabhu, Eric K. Lin
Chemically amplified photoresists are likely to remain the primary imaging materials for the semiconductor industry. As feature sizes decrease to dimensions comparable to the characteristic size of the molecules in the photoresist, a significant challenge

Crystallization-Induced Fluid Flow in Polymer Melts Undergoing Solidification

February 19, 2007
Author(s)
Donghua Xu, Z G. Wang, Jack F. Douglas
The formation of semi-crystalline plastic polymer materials often occurs under confinement conditions where high pressure imprinting or casting in a mold are involved. To gain insight into this highly non-equilibrium process, we examine the nature of the

Osteocyte Enhancement of Angiogenesis In Vitro

February 14, 2007
Author(s)
Erica Takai, Juan M. Taboas, Rocky Tuan, Steven D. Hudson
It is well known that an intimate relationship exists between vascularization and bone formation during development and fracture healing, where new bone formation is preceded by local vascularization. A recent rat exercise model has demonstrated that

Traceable Micro-Force Calibration for Instrumented Indentation Testing

February 13, 2007
Author(s)
Douglas T. Smith, Gordon A. Shaw, Richard Seugling, Jon R. Pratt, Dan Xiang
We describe the development, performance and application of an accurate SI-traceable force calibration and verification system for potential use in the field calibration of commercial instrumented indentation testing (IIT) instruments. The system consists

Characterization of Compositional Heterogeneity in Chemically Amplified Photoresist Polymer Thin Films with Infrared Spectroscopy

February 9, 2007
Author(s)
Shuhui Kang, B D. Vogt, Vivek Prabhu, Eric K. Lin, Wen-Li Wu, David L. VanderHart, Ashwin Rao, Karen Turnquest
We demonstrate a general approach to characterize compositional heterogeneity in polymer thin films using Fourier transform infrared (FTIR) spectroscopy. Polymer films with varying degrees of heterogeneity were prepared using a model chemically amplified

Mechanically Robust Spin-On Organosilicates Glasses for Nanoporous Applications

February 7, 2007
Author(s)
Hyun Wook Ro, K Char, Eun-Chae Jeon, H C. Kim, Dongil Kwon, Hae-Jeong Lee, J. H. Lee, Hee-Woo Rhee, Christopher L. Soles, Do Y. Yoon
An increasing number of technologies demand nanoporous materials with vastly improved physical, mechanical and thermal properties. This manuscript develops the microstructural basis for synthesizing organosilicate glasses (OSGs) with unprecedented thermal

Field-Induced Formation of Linear, Mesoscopic Polymer Chains From Ferromagnetic Nanoparticles

February 2, 2007
Author(s)
Jason Benkoski, Steven Bowles, Bryan Korth, Ronald L. Jones, Jack F. Douglas, Alamgir Karim, Jeffrey Pyun
Polymer-coated ferromagnetic colloids are first assembled with an applied magnetic field and then permanently fixed into one-dimensional mesostructures using a novel liquid-liquid interfacial system known as Fossilized Liquid Assembly. Using polystyrene

NCMC Workshop ReportNCMC-10: Persistent Challenges in Combinatorial Materials Science

February 1, 2007
Author(s)
Michael J. Fasolka, Carol E. Laumeier, Kathryn L. Beers, Christopher M. Stafford
Tremendous advances in the development and application of combinatorial and high-throughput methods for materials research have been accomplished over the past 15 years. Despite these accomplishments, today s combinatorial materials science is met by some

Combinatorial Materials Science: Measures of Success

January 30, 2007
Author(s)
Michael J. Fasolka, Eric J. Amis
points across parameter space. When designed effectively, combinatorial libraries explore a range of parameters in a rational and reliable manner. Second, where traditional experiments test and analyze samples in a one at a time mode, combinatorial

Pattern-directed to isotropic dewetting transition in polymer films on micropatterned surfaces with differential surface energy contrast

January 27, 2007
Author(s)
D Julthongpiput, Wenhua Zhang, Jack F. Douglas, Alamgir Karim, Michael J. Fasolka
Surface chemical patterns can both cause and direct dewetting in overlying thin films. However, a key factor in this behavior, the magnitude of surface energy differences between pattern domains ( ?g ), is largely unevaluated. To probe the effect of this

Measuring Molecular Order in Poly(3-alkylthiophene) Thin Films with Polarizing Spectroscopies

January 16, 2007
Author(s)
Marc Gurau, Dean DeLongchamp, Brandon M. Vogel, Eric K. Lin, Daniel A. Fischer, S Sambasivan, Lee J. Richter
We measured the molecular order of poly(3-alkylthiophene) chains in thin films before and after melting through the combination of several polarized photon spectroscopies: infrared (IR) absorption, variable angle spectroscopic ellipsometry (SE), and near

Anisotropic Wetting on Tunable Micro-Wrinkled Surfaces

January 1, 2007
Author(s)
Jun Y. Chung, Jeffrey Youngblood, Christopher M. Stafford
We demostrate that the buckling instability technique is promising for studying wettability because key elements of surface topography such as surface roughness can be precisely controlled by simple changes in experimental conditions. For demonstration, we

Buckling Modes of Elastic Thin Films on Elastic Substrates

January 1, 2007
Author(s)
Haixia Mei, Jun Y. Chung, Honghui Yo, Christopher Stafford, Rui Huang
Subject to compression, a thin elastic film bonded to an elastic substrate can buckle. Two buckling modes have been observed. On a stiff substrate, the film buckles when it is partly delaminated from the substrate, resulting in localized buckle patterns

Combinatorial screening of the effect of temperature on the microstructure and mobility of a high performance polythiophene semiconductor

January 1, 2007
Author(s)
Leah A. Lucas, Dean M. DeLongchamp, Brandon M. Vogel, Eric K. Lin, Michael J. Fasolka, Daniel A. Fischer, Iain McCulloch, Martin Heeney, Ghassan Jabbour
Using a gradient combinatorial approach, the authors report the effects of temperature on the microstructure and hole mobility of poly2,5-bis3-dodecylthiophen-2ylthieno3,2-bthiophene thin films for application in organic field-effect transistors. The

Effect of Surface Properties on Wrinkling of Ultrathin Films

January 1, 2007
Author(s)
Rui Huang, Christopher Stafford, B D. Vogt
Thin films bonded to compliant substrates often develop wrinkles when subjected to an applied or inherent compressive stress. This paper presents a bilayer model to account for surface effects on the wrinkling of ultrathin solid films. Assuming a surface

Fabrication Strategies for Producing Gradient Roughness Libraries

January 1, 2007
Author(s)
Christopher Stafford, Jun Y. Chung, Xuesong Hu, Heqing Huang
New technologies, such as flexible electronics and functional coatings systems, consist of hierarchical structures fabricated out of combinations of both soft and hard materials, with each material type lending unique properties and performance

Length Dependent Uptake of DNA-Wrapped Single Walled Carbon Nanotubes

January 1, 2007
Author(s)
Matthew Becker, Jeffrey Fagan, Nathan D. Gallant, Barry J. Bauer, Vardhan Bajpai, Erik K. Hobbie, Silvia H. De Paoli Lacerda, Kalman D. Migler, J P. Jakupciak
DNA-wrapped single wall carbon nanotubes (SWNTs) with broad length distributions are shown to reduce the viability of IMR90 primary human lung fibroblast cells above the (23 to 25) ug/mL concentration regime. Furthermore using well-defined length fractions
Displaying 1326 - 1350 of 1856