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Displaying 1276 - 1300 of 2361

Influence of Pressure on Glass Formation in a Simulated Polymer Melt

October 18, 2016
Author(s)
Jack F. Douglas, Wensheng Xu, Karl Freed
We investigate the thermodynamic and dynamic properties of a model unentangled glass-forming polymer melt over a wide range of pressures (P) and temperatures (T) using molecular dynamics simulation. We show that the T dependence of the reduced thermal

Supramolecular Self-assembly of a Novel Hydrogelator: Characterization of Fiber Morphology and Formation and Thermal-Reversible Gelation

October 8, 2016
Author(s)
Jack F. Douglas, Yuan Gao Yuan Gao, Ryan C. Nieuwendaal, Emilios Dimitriadis, Boualem Hammouda, Bing Xu, Ferenc Horkay
Hydrogels are of intense recent interest in connection with biomedical applications ranging from 3-D cell cultures and stem cell differentiation to regenerative medicine, controlled drug delivery and tissue engineering. This prototypical form of soft

Correlation Between Morphology and Device Performance of pBTTT:PC 71 BM Solar Cells

October 1, 2016
Author(s)
Wenluan Zhang, Hao Shen, Brett W. Guralnick, Brian Kirby, Ngoc A. Nguyen, Roddel Remy, Charles Majkrzak, Michael E. Mackay
Phenyl-C 71-butyric acid methyl ester (PC 71BM) could intercalate between the side-chains of poly(2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene (pBTTT) creating a stable co-crystal structure, so optimal solar cell performance was obtained at

Atomically Engineered Ferroic Layers Yield a Room-Temperature Magnetoelectric Multiferroic

September 21, 2016
Author(s)
Julia A. Mundy, Charles M. Brooks, Megan E. Holtz, Jarrett A. Moyer, Hena Das, Alejandro F. Rebola, John T. Heron, James D. Clarkson, Steven M.T. Disseler, Zhiqi Liu, Alan Farhan, Rainer Held, Robert Hovden, Elliot Padgett, Qingyun Mao, Hanjong Paik, Rajiv Misra, Lena F. Kourkoutis, Elke Arenholz, Andreas Scholl, Julie Borchers, William D. Ratcliff, Ramamoorthy Ramesh, Craig J. Fennie, Peter Schiffer, David A. Muller, Darrell G. Schlom
The defining feature of ferroics is the ability of an external stimulus - electric field, magnetic field, or stress-to move domain walls. These topological defects and their motion enables many useful attributes, e.g., memories that can be reversibly

The Glass Transition of a Single Macromolecule

September 21, 2016
Author(s)
Jack F. Douglas, David Simmons, Weston L. Merling, Jack Mileski
The glass transition of a single macromolecule in isolation is relevant to the dynamics of systems including dilute solutions of synthetic polymers and biological macromolecules such as proteins. Here we employ molecular dynamics simulation to show that a

A Q-band free-space characterization of carbon nanotube composites

September 19, 2016
Author(s)
Ahmed M. Hassan, Jan Obrzut, Edward Garboczi
We present a free-space measurement technique for non-destructive non-contact electrical and dielectric characterization of nano-carbon composites in the Q-band frequency range of 30 GHz to 50 GHz. The experimental system and error correction model

The Center for Research on Extreme Batteries

September 19, 2016
Author(s)
Eric Wachsman, Cynthia Lundgren, Esther S. Takeuchi, Kang Xu, Chunsheng Wang, Joseph Dura, David L. Jacobson, Kahlil Amine, William Acker
How much would you spend on a battery if your life depended on it? Rarely is that question asked as the vast majority of battery development is focused on bringing down battery cost for wide spread consumer acceptance. However, for many industries

Towards Building Simulation Tools for Next Generation Soft Body Armour Testing Standards

September 18, 2016
Author(s)
Steven P. Mates, Amanda L. Forster, Michael A. Riley, Kirk D. Rice, Juliana Ivancik
Accurate simulation tools for soft body armour testing would vastly improve test designer's ability to optimize and refine standards by supplying quantitative information about the influence of test variables on test outcomes. Such tools would also

Film morphology evolution during solvent vapor annealing of highly efficient small molecule donor/acceptor blends

September 15, 2016
Author(s)
Sebastian Engmann, Hyun W. Ro, Andrew Herzing, Chad R. Snyder, Lee J. Richter, Paul Geraghty, David Jones
Solution-processable small molecule photovoltaics based on the novel molecular donor, benzodithiophene terthiophene rhodamine (BTR), recently have shown maximum power conversion efficiencies above 8% for active layer thicknesses up to 400 nm, using post

Thermodynamics of Cottrell atmospheres tested by atomistic simulations

September 15, 2016
Author(s)
Yuri Mishin, John W. Cahn
Solute atoms can segregate to elastically deformed lattice regions around a dislocation and form an equilibrium distribution called the Cottrell atmosphere. We compare two approaches to describe Cottrell atmospheres. In the Eshelby theory, the solid

Three-Dimensional Protonic Conductivity in Porous Organic Cage Solids

September 13, 2016
Author(s)
Ming Liu, Linjiang Chen, Scott Lewis, Samantha Y. Chong, Marc A. Little, Tom Hasell, Iain M. Aldous, Craig Brown, Martin W. Smith, Carole A. Morrison, Laurence J. Hardwick, Andrew I. Cooper
Proton conduction is a fundamental process in biology and in devices such as proton exchange membrane fuel cells. To maximize proton conduction, 3-D conduction pathways are preferred over 1-D pathways, which prevent proton conduction in two-dimensions

Conformational Nature of DNAGrafted Chains on Spherical Gold Nanoparticles

September 10, 2016
Author(s)
Jack F. Douglas, Fernando Vargas-Lara
We investigate the conformational state of a simple, coarse–grained molecular model for single–stranded DNA chains (ss-DNA) grafted onto spherical symmetric gold nanoparticles (NPs) and of the grafted layer as a whole by molecular dynamic simulations. In

Structural and Dynamical Trends in Alkali-Metal Silanides Characterized by Neutron-Scattering Methods

September 2, 2016
Author(s)
Wan Si NMN Tang, Mirjana NMN Dimitrievska, Jean-Noel Chotard, Wei Zhou, Raphael Janot, Alexander V. Skripov, Terrence J. Udovic
Structural, vibrational, and dynamical properties of the mono- and mixed-alkali silanides (MSiH 3, where M=K, Rb, Cs, K 0.5Rb 0.5Cs 0.5, and Rb 0.5Cs 0.5) were investigated by various neutron experiments, including neutron powder diffraction (NPD), neutron

Stabilizing Superionic-Conducting Structures via Mixed-Anion Solid Solutions of Monocarba-Closo-Borate Salts

September 1, 2016
Author(s)
Wan Si NMN Tang, Koji Yoshida, Alexei V. Soloninin, Roman V. Skoryunov, Olga A. Babanova, Alexander V. Skripov, Mirjana NMN Dimitrievska, Vitalie Stavila, Shin-Ichi Orimo, Terrence J. Udovic
Solid lithium and sodium closo-polyborate-based salts are capable of superionic conductivities surpassing even liquid electrolytes, but often only at above-ambient temperatures where their entropically driven disordered phases become stabilized. Here we

Ultraviolet photodetectors based on transition metal oxides

September 1, 2016
Author(s)
Ratan K. Debnath, Albert Davydov
Ultraviolet (UV) photodetector (PD) has attracted extensive attention owing to their broad application in digital imaging, missile plume detection, optical communications, and biomedical sensing. Conventional Si based UV PD requires costly high pass
Displaying 1276 - 1300 of 2361
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