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Search Publications

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Displaying 351 - 375 of 1856

Highly Efficient Rapid Annealing of Thin Polar Polymer Film Ferroelectric Devices at Sub-Glass Transition Temperature

December 18, 2017
Author(s)
Vasileia Georgiou, Dmitry Veksler, Jason T. Ryan, Jason P. Campbell, Pragya R. Shrestha, D. E. Ioannou, Kin P. Cheung
An unexpected rapid anneal of electrically active defects in an ultra-thin (15.5 nm) polar polyimide film at and below glass transition temperature (Tg) is reported. The polar polymer is the gate dielectric of a thin-film-transistor (TFT). Gate leakage

Spatial Distribution of Hydrophobic Drugs in Model Nanogel-core Star Polymers

December 5, 2017
Author(s)
Vivek M. Prabhu, Guangmin Wei, Robert D. Miller, Victoria A. Piunova, William Swope, Amber Carr
Star polymers with a cross-linked nanogel-core are promising carriers of cargo for therapeutic applications due the synthetic control of amphiphilicity of arms and the stability to infinite dilution. Three nanogel-core star polymers were investigated to

Modeling the polarized X-ray scattering from periodic nanostructures with molecular anisotropy

December 1, 2017
Author(s)
Christopher D. Liman, Thomas A. Germer, Daniel F. Sunday, Dean M. DeLongchamp, Regis J. Kline
We discuss a new technique to measure molecular orientation in nanostructures using resonant soft X-rays. This technique is based on a variable angle transmission measurement called critical dimension X-ray scattering that enables the characterization of

Free Surface Relaxations of Star-Shaped Polymer Films

November 28, 2017
Author(s)
Alexandros Chremos, Bradley R. Frieberg, Emmanouil Glynos, Kyle Johnson, Hengxi Yang, Suresh Narayanan, Peter F. Green, Georgios Sakellariou
X-ray photon correlation spectroscopy (XPCS) studies show that the viscosities of thin film linear chain polymers at temperatures sufficiently high above the bulk glass transition temperature Tg bulk are equal to the bulk zero shear viscosities. The free

Towards a Hybrid Human-Computer Scientific Information Extraction Pipeline

November 27, 2017
Author(s)
Roselyne B. Tchoua, Kyle Chard, Debra Audus, Logan T. Ward, Lequieu Joshua, Juan J. de Pablo, Ian Foster
The emerging field of materials informatics has the potential to greatly reduce time-to-market and development costs for new materials. The success of such efforts hinges on access to large, high-quality databases of material properties. However, many such

Service Life Prediction -Why is this so hard?

November 8, 2017
Author(s)
Christopher C. White, Kenneth M. White, James Pickett
Service life prediction in general and weathering lifetime in particular have been persistent problems despite nearly a century of work. Part of the problem has been a gap between the work of scientists studying material degradation and the practices

Buckling Instabilities in Polymer Brush Surfaces via Postpolymerization Modification

October 30, 2017
Author(s)
Wei Guo, Cassandra M. Reese, Li Xiong, Phillip K. Logan, Brittany J. Thompson, Christopher Stafford, Anton Ievlev, Bradley S. Lokitz, Olga S. Ovchinnikova, Derek L. Patton
We report a simple route to engineer ultrathin polymer brush surfaces with wrinkled and creased morphologies using postpolymerization modification (PPM), where the length scale of the buckled features can be tuned using PPM reaction time and sequence. We

Knot Energy, Complexity, and Mobility of Knotted Polymers

October 17, 2017
Author(s)
Luis F. Vargas Lara, Ahmed M. Hassan, Marc A. Mansfield, Jack F. Douglas
The Newtonian capacity C of an object is defined by the equilibrium energy, EN =1/C, of a charge distribution on a conductive object and provides a classical measure of object shape. It is well known, for example, that C is minimized for a sphere for all

Wrinkling-to-delamination transition in thin polymer films on compliant substrates

October 9, 2017
Author(s)
Adam J. Nolte, Jun Y. Chung, Chelsea S. Davis, Christopher Stafford
Compressing a thin, stiff film attached to a thick, compliant substrate can lead to a number of different modes of mechanical deformation depending upon the material properties of the system. In this article we explore direct transitions from surface

Nanostructural Evidence of Mechanical Aging and Performance Loss in Ballistic Fibers

September 29, 2017
Author(s)
John Howarter, Ming Liu, Walter G. McDonough, Christopher Soles, Gale A. Holmes
It is understood that the ballistic resistance of aromatic polyamide fibers is related to the fiber's ultimate tensile strength, strain-to-failure, and Young's modulus. Ideal high-performance ballistic materials maximize these properties while minimizing

Simple Transfer from Spin Coating to Blade Coating Through Processing Aggregated Solutions

September 22, 2017
Author(s)
Jeff L. Hernandez, Nabankur Deb, Rylan M. Wolfe, Chi K. Lo, Sebastian Engmann, Lee J. Richter, John R. Reynolds
To develop an understanding of the effect spin coating or blade coating have on the morphology of polymer:fullerene thin films for organic solar cells, we have investigated the morphology of poly[5-(2-hexyldecyl)-1,3-thieno[3,4-c]pyrrole-4,6-dione-alt-5,5-

Enhanced durability of CNT based hierarchical composites subjected to accelerated aging environments.

September 21, 2017
Author(s)
Ajay Krishnamurthy, Donald L. Hunston, Amanda L. Forster, Bharath NMN Natarajan, Sunny Wicks, Paul E. Stutzman, James A. Liddle, Aaron M. Forster, Brian L. Wardle
As carbon nanotube (CNT) based composites are increasingly being identified as viable aerospace materials, it is vital to study their environmental degradation characteristics. In this work, the durability of CNT reinforced hierarchical alumina fiber

Polymer Informatics: Opportunities and Challenges

September 15, 2017
Author(s)
Debra J. Audus, Juan J. de Pablo
We are entering an era where large volumes of scientific data, coupled with algorithmic and computational advances, can reduce both the time and cost of developing new materials. This emerging field known as materials informatics has gained acceptance for

Strain Measurement of 3D Structured Nanodevices by EBSD

August 20, 2017
Author(s)
William A. Osborn, Lawrence H. Friedman, Mark D. Vaudin
We present a new methodology to accurately measure strain magnitudes from 3D nanodevices using Electron Backscatter Diffraction (EBSD). Because the dimensions of features on these devices are smaller than the interaction volume for backscattered electrons

Moisture Uptake Characterization in Nanocellulose Using Microwave Cavity

August 17, 2017
Author(s)
Caglar Emiroglu, Bharath N. Natarajan, Jeffrey W. Gilman, James Alexander Liddle, Jan Obrzut
Cellulose nanocrystal films with different helical modulation lengths are characterized. Films are obtained by tuning the rate of evaporation and surface functionalization. Dielectric constant measurements are performed and the water confinement is

Epitaxially-grown self-assembled Bi2Se3/Bi2MnSe4 multilayer heterostructures

August 14, 2017
Author(s)
Joseph A. Hagmann, Xiang Li, Si-Ning Dong, Sergei Rouvimov, Sujitra J. Pookpanratana, Kin Man Yu, Tatyana Orlova, Curt A. Richter, David G. Seiler, Xinyu Liu, Jacek K. Furdyna, Margaret Dobrowolska
Progress in understanding topologically non-trivial systems offers the promise of predicting novel systems that demonstrate the remarkable properties associated with topological systems, such as unidirectional spin-polarized surface current and the
Displaying 351 - 375 of 1856