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Search Publications

NIST Authors in Bold

Displaying 1576 - 1600 of 2122

Influence of chain stiffness on thermal and mechanical properties of polymer thin films

October 25, 2011
Author(s)
Jessica M. Torres, Chengqing C. Wang, E. B. Coughlin, John P. Bishop, Richard A. Register, Robert A. Riggleman, Christopher Stafford, Bryan D. Vogt
The effect of main chain stiffness and side chain flexibility on the elastic modulus and glass transition temperature (Tg) of thin polymer films is investigated using non-traditional polymers formed from 5-(2-phenylethylnorbornene). Depending on the

Abstract of the presentation: Position- and polarization- resolved microphotoluminescence of GaN/AlGaN core-shell nanowires

October 17, 2011
Author(s)
Albert Davydov, G. Jacopin, S. Bellei, Denis Tsvetkov, Kristine A. Bertness, L. Rigutti, Norman A. Sanford, John B. Schlager, M. Tchernycheva, F. H. Julien
Over the past decade, core-shell nanowires (NWs) have been intensively used as the building blocks of novel optoelectronic devices as solar cells [1], LEds [2], naolasers [3]. Indeed, this geometry not only allows to passivate surface states, but also

Morphological Changes Driven by Nanofibrous Scaffolds Induce Marrow Stromal Cell Osteogenesis

October 11, 2011
Author(s)
Carl G. Simon Jr., Kaushik Chatterjee, Christopher K. Tison, Girish Kumar, Patrick S. Pine, Marc L. Salit, Jennifer H. McDaniel, Marian F. Young
Cells are sensitive to tissue scaffold architecture and these cell-material interactions drive cell functions critical in tissue regeneration. Results presented here demonstrate that nanofiber scaffolds force primary human bone marrow stromal cells (hBMSCs

Effect of Moisture on Copolymer Fibers based on 5-amino-2-(p-aminophenyl)-benzimidazole

October 4, 2011
Author(s)
Guillaume Messin, Stephanie S. Watson, Amanda L. Forster, John R. Sieber
In recent years, there has been concern in the soft body armor community that copolymer fibers based on 5-amino-2-(p-aminophenyl)-benzimidazole can release hydrochloric acid, which could potentially be detrimental to other fibers that might come in contact

Service Life Prediction for Sealants

September 29, 2011
Author(s)
Christopher C. White, Donald L. Hunston, Kar T. Tan, James J. Filliben
Previous industry consensus postulated that four elements of the weather: Temperature, Humidity, Ultraviolet Radiation, and Mechanical loading were responsible for the majority of the changes observed in sealants exposed to outdoor weathering. The NIST

Formation and transfer of GaAsN nanostructure layers

September 27, 2011
Author(s)
Christopher L. Soles, Hyun W. Ro, A. Wood, N. Estrada, B. Dick, Y. Wang, Micheal Thouless, Rachel Goldman
Nanostructured materials with ultra-small crystallites (approaching the exciton Bohr radius) embedded in a solid-state matrix have great potential for optoelectronic and energy-conversion applications owing to the possibility of invoking quantum effects

Molecular Order in High-Efficiency Polymer/Fullerene Bulk Heterojunction Solar Cells

September 22, 2011
Author(s)
Matthew R. Hammond, Regis J. Kline, Andrew A. Herzing, Lee J. Richter, David Germack, Hyun W. Ro, Christopher L. Soles, Daniel A. Fischer, Tao Xu, Luping Yu, Michael F. Toney, Dean M. DeLongchamp
We report quantitative measurements of ordering, molecular orientation, and nanoscale morphology in the active layer of bulk heterojunction organic photovoltaic cells based on a thieno[3,4-b]thiophene-alt-benzodithiophene copolymer (PTB7), which has been

Block copolymer photonic gel for mechanochromic sensing

September 19, 2011
Author(s)
Edwin Chan, Joseph J. Walish, Edwin L. Thomas, Christopher Stafford
In this work, we describe a strategy based on mechanochromic sensing, the coupling between mechanical and optical properties, of a block copolymer photonic gel. Although this phenomena has been observed in many materials, we demonstrate this concept for

Magnetization textures in NiPd nanostructures

September 15, 2011
Author(s)
Jean-Yves Chauleau, Benjamin James McMorran, R. Belkhou, Nicolas Bergeard, Tevfik Mente?, Miguel Angel Nino, Andrea Locatelli, John Unguris, Stanislas Rohart, Jacques Miltat, Andre Thiaville
We have observed peculiar magnetization textures in Ni80Pd20 nanostructures, by three different imaging techniques (MFM, XMCD-PEEM and SEMPA). The appearance of diamond-like domains with strong lateral charges, and of weak stripes structures brings into

Structure of lithium peroxide

September 12, 2011
Author(s)
Eric L. Shirley, Maria K. Chan, Naba Karan, Mahalingam Balasubramanian, Yang Ren, Jeffrey P. Greeley, Timothy T. Fister
The reliable identification of lithium oxides species, especially lithium peroxide (Li2O2), is of vital importance to the study of Li-air batteries. Previous x-ray diffraction studies of Li2O2 resulted in the proposal of two disparate structures by Féher

Modeling electromigration using the peridynamics approach

August 28, 2011
Author(s)
David T. Read, Walter Gerstle, Vinod K. Tewary
This chapter presents a summary of the information and reasoning needed to justify learning about peridynamics for the purpose of analyzing electromigration and provides guidance for the development of a complete peridynamics analysis. The additions needed

Graphene-metal interconnect: an atomistic simulation

August 11, 2011
Author(s)
Alexander Y. Smolyanitsky, Vinod K. Tewary
We develop a set of computationally efficient and accurate interatomic interactions for an atomistic simulation of the properties of graphene on nickel surface. The approach is based on the modified embedded atom method (MEAM) for the C-C and Ni-Ni

Design and Optimization of a Permeation Testing System for Polymer Coatings

August 8, 2011
Author(s)
Adrian E. Verwolf
Measurements of liquid permeation through freestanding Parylene C membranes were made using a high- performance testing system, which demonstrated fast response (≤ 30 seconds) to changing concentrations in the sweep gas stream and detectability of less
Displaying 1576 - 1600 of 2122