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Search Publications

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Displaying 376 - 400 of 1856

Weld formation during material extrusion additive manufacturing

August 11, 2017
Author(s)
Jonathan E. Seppala, Seung Hoon Han, Kaitlyn E. Hillgartner, Chelsea S. Davis, Kalman D. Migler
Material extrusion (ME) is a layer-by-layer additive manufacturing process that is now used in personal and commercial production where prototyping and customization are required. However, parts produced from ME frequently exhibit poor mechanical

Energy renormalization approach to coarse-graining of polymer dynamics

August 8, 2017
Author(s)
Wenjie Xia, Jake Song, Cheol Jeong, David D. Hsu, Frederick R. Phelan Jr., Jack F. Douglas, Sinan Keten
A major challenge in soft matter science is the bottom-up prediction of the temperature- dependent behavior of amorphous glass-forming (GF) polymers. Coarse-grained (CG) models derived from atomistic simulation data offer chemical specificity and access to

Influence of polymer architecture on diffusion in polymers melts

August 2, 2017
Author(s)
Alexandros Chremos, Cheol Jeong, Jack F. Douglas
Recent simulations have indicated that the thermodynamic properties and the glassy dynamics of polymer melts are strongly influenced by average molecular shape, as quantified by the radius of gyration tensor of the polymer molecules, and that average

Measurement and Modeling of the Ability of Crack Fillers to Prevent Chloride Ingress into Mortar

August 1, 2017
Author(s)
Scott Z. Jones, Dale P. Bentz, Jeffrey Davis, Daniel S. Hussey, David L. Jacobson, John L. Molloy, John R. Sieber
One of the most common repair procedures applied to damaged concrete is the filling of cracks by the application (injection) of an organic polymer. This operation is performed to increase the service life of the concrete by removing a preferential pathway

Fast-Responding Bio-Based Shape Memory Thermoplastic Polyurethanes

July 14, 2017
Author(s)
Zoran S. Petrovic, Jelena Milic, Fan Zhang, Jan Ilavsky
Fast response shape-memory polyurethanes were prepared from bio-based polyols, diphenyl methane diisocyanate and butane diol. The bio-based polyester polyols were synthesized from 9-hydroxynonanoic acid, a product obtained by ozonolysis of fatty acids

Universal Interrelation Between Measures of Particle and Polymer Size

July 6, 2017
Author(s)
Luis F. Vargas Lara, Marc L. Mansfield, Jack F. Douglas
The characterization of many objects often involves the determination of a basic set of particle size measures derived mainly from scattering and transport property measurements. For polymers, these basic properties often include the radius of gyration Rg

Metrologies for Performance of Impact Mitigating Materials

June 12, 2017
Author(s)
Aaron M. Forster, Michael A. Riley
Soft non-linear materials are used to mitigate energy transfer between objects during high rate or frequency events. These impact mitigating materials (IMM) are used in a wide range of applications such as isolating rotating equipment, protecting buildings

Void-based Assembly of Colloidal Crystals

June 1, 2017
Author(s)
Nathan Mahynski, Lorenzo Rovigatti, Christos Likos, Athanassios Panagiotopoulos
We have used computer simulations to reveal how colloidal crystals may be assembled by engineering the shape and charge of polymeric additives, which act as structure-directing agents (SDAs). Using these agents, only a single desired polymorph may be

Interacting nanoscale magnetic cluster arrays in molybdenum oxide bronzes

May 26, 2017
Author(s)
Joseph A. Hagmann, Son T. Le, Lynn F. Schneemeyer, Joseph A. Stroscio, Tiglet Besara, Theo Siegrist, Curt A. Richter, David G. Seiler
In this study, we examine several reduced ternary molybdates in the family of rare earth molybdenum bronzes produced by electrochemical synthesis with composition LnMo16O44. These compounds contain an array of electrically isolated but magnetically

Morphological characterization of fullerene and fullerene-free organic photovoltaics by combined real and reciprocal space techniques

May 26, 2017
Author(s)
Donglin Zhao, Qinghe Wu, Luping Yu, Harald Ade, Dean DeLongchamp, Lee J. Richter, Subhrangsu Mukherjee, Andrew Herzing
Morphology can play a critical role in determining function in organic photovoltaic (OPV) systems. Recently molecular acceptors have showed promise to replace¬ fullerene derivatives as acceptor materials in bulk heterojunction solar cells and have achieved

Impact of RRAM Read Fluctuations on the Program-Verify Approach

May 22, 2017
Author(s)
David M. Nminibapiel, Dmitry Veksler, Pragya Shrestha, Jason Campbell, Jason Ryan, Helmut Baumgart, Kin P. Cheung
The stochastic nature of the conductive filaments in oxide-based resistive memory (RRAM) represents a sizeable impediment to commercialization. As such, program-verify methodologies are highly alluring. However, it was recently shown that program-verify

Graphene microcapsule arrays for combinatorial electron microscopy and spectroscopy in liquids

April 27, 2017
Author(s)
Alexander Yulaev, Hongxuan Guo, Evgheni Strelcov, Lei Chen, Ivan Vlasssiouk, Andrei Kolmakov
An atomic-scale thickness, molecular impermeability, low atomic number, and mechanical strength make graphene an ideal electron transparent membrane for scanning electron microscopy and spectroscopy in liquids. Here, we present a novel sample platform made

The dependence of electrical performance on structural organization in low mobility polymer field effect transistors

April 16, 2017
Author(s)
Emily G. Bittle, Hyun W. Ro, Chad R. Snyder, Sebastian Engmann, Regis J. Kline, Oana Jurchescu, Dean M. DeLongchamp, David J. Gundlach
Polymer semiconductors are contenders for use in printed, flexible electronics. Though organic electronic materials have been studied for many years, the physics of charge transport is still under investigation. This is in part due to the large variability
Displaying 376 - 400 of 1856