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Displaying 551 - 575 of 1926

Atomic structural evolution during the reduction of a-Fe2O3 nanowires

June 20, 2016
Author(s)
Wenhui Zhu, Jonathan P. Winterstein, Itai Maimon, Qiyue Yin, Lu Yuan, Aleksey N. Kolmogorov, Renu Sharma, Guangwen Zhou
The atomic-scale reduction mechanism of α-Fe2O3 nanowires by H2 was followed using transmission electron microscopy to reveal the evolution of atomic structures and the associated transformation pathways for different iron oxides. The reduction commences

Evolution of Dendrimer Conformational Structure with Generation Number

June 20, 2016
Author(s)
Beatriz A. Pazmino, Jack F. Douglas
We simulate the conformational structure of a coarse-grained model of dendrimer molecules in good solvent as a function of generation number G and find that they evolve through a substantially more complex structures than regular star polymer with

Hydrodynamic Radius Fluctuations in Model DNA-Grafted Nanoparticles

June 16, 2016
Author(s)
Luis Fernando Vargas Lara, Francis W. Starr, Jack F. Douglas
We utilize molecular dynamics simulations (MD) and the path-integration program ZENO to quantify hydrodynamic radius (Rh) fluctuations of spherical symmetric gold nanoparticles (NPs) decorated with single-stranded DNA chains (ssDNA). In particular, we

Three-Phase Statistically Equivalent Periodic Unit Cells for Protein-Bound Soils

May 25, 2016
Author(s)
Edward Garboczi, Isamar Rosa, Michael Lepech, Henning Roedel, David Loftus
This work focuses on a novel class of composites that can be produced extraterrestrially, or in situ, by desiccating a mixture of soil, water, and protein binder to create a strong, versatile material. To date, experimental tests of mechanical properties

STANDARD REFERENCE MATERIALS FOR THE POLYMERS INDUSTRY

May 24, 2016
Author(s)
Walter G. McDonough, Sara Orski, Charles M. Guttman, Kalman Migler, Kathryn L. Beers
The National Institute of Standards and Technology (NIST) provides science, industry, and government with a central source of well-characterized materials certified for chemical composition or for some chemical or physical property. These materials are

Thermography and Weld Strength Characterization of Thermoplastic Extrusion 3D Printing

May 23, 2016
Author(s)
Jonathan E. Seppala, Kaitlyn E. Hillgartner, Chelsea S. Davis, Kalman D. Migler
In fused filament fabrication (FFF), a material extrusion additive manufacturing (AM) method, thermoplastic filament is extruded though a rastering nozzle on prior layers building a 3 dimensional object. The resulting strength of the FFF produced part is

Characterization of Buried Interfaces with Scanning Probe Microscopes

May 19, 2016
Author(s)
Joseph J. Kopanski, Lin You, Jungjoon Ahn, Yaw S. Obeng
Scanning probe microscopes (SPMs) have some capability to image sub-surface structure, including the details of buried interfaces. This paper describes the theoretical and practical basis for obtaining information about shallow buried interfaces

Structural and optical nanoscale analysis of GaN core-shell microrod arrays fabricated by combined top-down and bottom-up process on Si (111)

May 15, 2016
Author(s)
Sergiy Krylyuk, Marcus Muller, Gordon Schmidt, Sebastian Metzner, Peter Veit, Frank Bertram, Ratan K. Debnath, Jong Yoon Ha, Baomei Wen, Paul T. Blanchard, Alexana Roshko, Abhishek Motayed, Matthew R. King, Albert Davydov, Jurgen Christen
Large arrays of GaN core-shell microrods were fabricated on Si(111) substrates applying a combined bottom-up and top-down approach which includes inductively coupled plasma (ICP) etching of patterned GaN films grown by metal-organic vapor phase epitaxy

Pattern-Directed Phase Separation of Polymer-Grafted Nanoparticles in a Homopolymer Matrix

May 12, 2016
Author(s)
Ren Zhang, Bongjoon Lee, Michael R. Bockstaller, Sanat K. Kumar, Christopher Stafford, Jack F. Douglas, Dharmaraj Raghavan, Alamgir Karim
The controlled organization of nanoparticle (NP) constituents into superstructures of well- defined shape, composition and connectivity represents a continuing challenge in the development of novel hybrid materials for many technological applications. We

Enhancing Single-Wall Carbon Nanotube Properties Through Controlled Endohedral Filling

May 10, 2016
Author(s)
Jochen I. Campo, Yanmei Piao, Stephanie Lam, Christopher Stafford, Jason K. Streit, Jeffrey R. Simpson, Angela R. Hight Walker, Jeffrey Fagan
Chemical control of the endohedral volume of single-wall carbon nanotubes (SWCNTs) via liquid-phase filling is demonstrated to be a facile strategy to controllably modify properties of the nanotubes in manners significant for processing and proposed

Rapid Fabrication of Poly(DL-lactide) Nanofiber Scaffolds with Tunable Degradation for Tissue Engineering Applications by Air-brushing

April 28, 2016
Author(s)
Adam M. Behrens, Jeffrey J. Kim, Nathan A. Hotaling, Jonathan Seppala, Peter Kofinas, Wojtek J. Tutak
Polymer nanofiber based materials have been widely investigated for use as tissue engineering scaffolds. While promising, these materials are typically fabricated through techniques that require significant time or cost. Here we report a cost effective

How to measure absolute P3HT crystallinity via 13C CPMAS NMR

April 20, 2016
Author(s)
Ryan C Nieuwendaal
We outline the details of acquiring quantitative 13C cross-polarization magic angle spinning (CPMAS) NMR spectra on the most ubiquitous polymer for organic electronics (OE) applications, poly(3-hexylthiophene) (P3HT), despite other groups’ claims that

Structural control of mixed ionic and electronic transport in conducting polymers

April 17, 2016
Author(s)
Jonathan Rivnay, Sahika Inal, Brian Collins, Michelle Sessolo, Eleni Stavrindou, Christopher Tassone, Dean DeLongchamp, George Malliaras
Poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate), PEDOT:PSS, has been utilized for over two decades as a stable, solution-processable conductor. While electrical properties have been the subject of intense materials investigation, recent

Device-Level Jitter as a Probe of Ultrafast Traps in High-k MOSFETs

April 16, 2016
Author(s)
Dmitry Veksler, Jason Campbell, Kin Cheung, J. Zhong, H. Zhu, C. Zhao
A methodology for evaluation of ultra-fast interfacial traps, using jitter measurements as a probe, is developed. This methodology is applied to study the effect of PBTI stress on density of ultra-fast electron traps (with 500ps to 5ns characteristic
Displaying 551 - 575 of 1926
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