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Search Publications

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Displaying 476 - 500 of 1856

Modeling early breakdown failures of gate oxide in SiC power MOSFETs

July 14, 2016
Author(s)
Zakariae Chbili, Asahiko Matsuda, Jaafar Chbili, Jason T. Ryan, Jason P. Campbell, Mhamed Lahbabi, D. E. Ioannou, Kin P. Cheung
One of the most serious technology roadblocks for SiC DMOSFETs is the significant occurrence of early failures in time-dependent-dielectric-breakdown (TDDB) testing. Conventional screening methods have proved ineffective because the remaining population is

Advancing X-Ray Scattering Metrology Using Inverse Genetic Algorithms

July 7, 2016
Author(s)
Adam F. Hannon, Daniel F. Sunday, Donald A. Windover, Regis J. Kline
We compare the speed and effectiveness of two genetic optimization algorithms to the results of statistical sampling via a Markov Chain Monte Carlo algorithm to find which is the most robust method for determining real space structure in periodic gratings

Rheology of clustering protein solutions

July 5, 2016
Author(s)
Vishnu Dharmaraj, P. Douglas Godfrin, Yun Liu, Steven Hudson
High viscosity is a major challenge with protein therapeutics at extremely high concentration. Understanding the relationship between the concentration of a protein solution and its viscosity as a function of shear rate and temperature is therefore

Attractive Interactions between DNA-Carbon Nanotube hybrids in Monovalent Salts

June 30, 2016
Author(s)
Ming Zheng, Xiangyun Qiu, Fuyou Ke, Raju Timsina, Constantine Y. Khripin
DNA-carbon nanotube (DNA-CNT) hybrids are nanometer-sized, highly-charged, rod-like molecules with complex surface chemistry, and their behaviors in aqueous solutions are governed by multifactorial interactions with both solvent and co-solutes. We have

A Hybrid Human-Computer Approach to the Extraction of Scientific Facts from the Literature

June 28, 2016
Author(s)
Roselyne B. Tchoua, Kyle Chard, Debra Audus, Jian Qin, Juan J. de Pablo, Ian Foster
A wealth of valuable data is locked within the millions of research articles published each year. Reading and extracting pertinent information from those articles has become an unmanageable task for scientists. This problem hinders scientific progress by

Machine Learning Strategy to Determine Cell Shape Phenotypes Associated with Micro-Environmental Cues

June 25, 2016
Author(s)
Desu Chen, Sumona Sarkar, Julian Candia, Carl G. Simon Jr., Wolfgang Losert, Joy P. Dunkers, Stephen J. Florczyk, Subhadip Bodhak, Meghan Driscoll
Cell morphology has been identified as a potential indicator of stem cell response and function in biomaterial environments. However, determination of cell shape phenotype in biomaterials is complicated by heterogeneous cell populations, heterogeneous

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

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
Displaying 476 - 500 of 1856