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Displaying 551 - 575 of 882

Electrical Characterization of Photoconductive GaN Nanowire Devices from 50 MHz to 33 GHz

July 1, 2011
Author(s)
Thomas M. Wallis, Dazhen Gu, Atif A. Imtiaz, Pavel Kabos, Paul T. Blanchard, Norman A. Sanford, Kristine A. Bertness, Christpher Smith
The electrical response of two-port., photoconductive GaN nanowire devices was measured from 50 MHz to 33 GHz. The admittance of individual contacted nanowires showed an increase on the order of 10% throughout the measured frequency range after exposure to

Evaluating the characteristics of multiwall carbon nanotubes

July 1, 2011
Author(s)
John H. Lehman, M. Terrones, Elisabeth Mansfield, Katie Hurst, Vincent Muenier
During the past 20 years, multiwall carbon nanotubes (MWCNTs) have become an important industrial material. Hundreds of tons are produced each year. This review is a survey of the scientific literature, motivated by industrial requirements and guidelines

Guided three-dimensional catalyst folding during Metal assisted Chemical Etching of Silicon

June 28, 2011
Author(s)
Konrad Rykaczewski, Owen J. Hildreth, Ching P. Wong, Andrei G. Fedorov, John H. Scott
In order to fabricate truly complex three-dimensional (3D) silicon nanostructures fabrication methods which expand beyond the concept of creation of straight 3D structures by direct extension of two dimensional (2D) patterns need to be developed. In recent

Hydrodynamic Fractionation of Finite Size Nano Gold Clusters

June 15, 2011
Author(s)
De-Hao D. Tsai, Tae Joon Cho, Frank W. DelRio, Julian S. Taurozzi, Michael R. Zachariah, Vincent A. Hackley
We demonstrate a high resolution in situ experimental method for performing simultaneous size-classification and characterization of functional nanoscale gold clusters (NGCs) based on asymmetric-flow field flow fractionation (AFFF). Field emission scanning

Physicochemical characterization and in vitro hemolysis evaluation of silver nanoparticles

June 7, 2011
Author(s)
Vytautas Reipa, Jonghoon Choi, Nam S. Wang, Victoria M. Hitchins, Peter L. Goering, Robert Malinauskas
In anticipation of the increased use of various forms of silver as an antimicrobial agent in medical devices, the objective of this study was to evaluate the in vitro hemolytic potential of silver nanoparticles in dilute human blood, and to relate particle

Humic Acid-Mediated Silver Nanoparticle Formation Under Environmentally Relevant Conditions

April 1, 2011
Author(s)
Nelson Akaighe, Robert I. MacCuspie, Divina A. Navarro, Diana S. Aga, Sarbajit Banerjee, Mary Sohn, Virender K. Sharma
The formation of silver nanoparticles (AgNPs) via reduction of silver ions (Ag+) in the presence of humic acids (HAs) under various environmentally relevant conditions is described. HAs tested were from Suwannee River (SUW), and samples of three sediment

Quantification and Compensation of Unintentional Analyte Aggregation in Electrospray Sampling

March 30, 2011
Author(s)
Mingdong M. Li, Suvajyoti S. Guha, Rebecca A. Zangmeister, Michael J. Tarlov, Michael R. Zachariah
Electrospray (ES) sources are commonly used to introduce non-volatile materials (e.g. nanoparticles, proteins, etc.) in to the gas phase for characterization by mass spectrometry and ion mobility. Recent studies in our group using electrospray ion mobility

Effects of shape distortions and imperfections on mode frequencies and collective linewidths in nanomagnets

March 28, 2011
Author(s)
Hans T. Nembach, Justin M. Shaw, Thomas J. Silva, Ward L. Johnson, Sudook A. Kim, Robert D. McMichael, Pavel Kabos
We used Brillouin light scattering to show that shape distortions in Ni80Fe20 nanoelements can have a dramatic effect on the measured linewidth of certain modes. By intentionally introducing an amount of “egg-like” shape distortion to an ideal elliptical

Modeling the transfer of line edge roughness from an EUV mask to the wafer

March 25, 2011
Author(s)
Gregg M. Gallatin, Patrick Naulleau
Contributions to line edge roughness (LER) from extreme ultraviolet (EUV) masks have recently been shown to be an issue of concern for both the accuracy of current resist evaluation tests as well the ultimate LER requirements for the 22 nm production node

Effects of Polyethyleneimine-Mediated Functionalization of Multi-Walled Carbon Nanotubes on Earthworm Bioaccumulation and Sorption by Soils

March 24, 2011
Author(s)
Elijah J. Petersen, Roger A. Pinto, Liwen Zheng, Qingguo Huang, Peter E. Landrum, Walter J. Weber
Carbon nanotubes (CNTs) are often modified for their different intended application potentials to enhance their aqueous stability or change properties such as their surface charge. Such changes may also profoundly impact their environmental behaviors. We

Challenges for Physical Characterization of Silver Nanoparticles Under Pristine and Environmentally Relevant Conditions

March 17, 2011
Author(s)
Robert I. MacCuspie, Kim Rogers, Manomita Patra, Zhiyong Suo, Andrew J. Allen, Matthew N. Martin, Vincent A. Hackley
The conditions used to disperse silver nanoparticles (AgNPs) strongly impact their resulting size measurements and agglomeration state, based on the underlying metrology and physical chemistry, respectively. A series of AgNP materials with reported

Effects of Ligand Monolayers on Catalytic Nickel Nanoparticles for Synthesizing Vertically Aligned Carbon Nanofibers

March 16, 2011
Author(s)
Kate L. Klein, Mehmet Sarac, Robert Wilson, Aaron C. Johnston-Peck, Junwei Wang, Ryan Pearce, Anatoli V. Melechko, Joseph B. Tracy
Vertically aligned carbon nanofibers (VACNFs) were synthesized using ligand-stabilized Ni nanoparticle (NP) catalysts and plasma-enhanced chemical vapor deposition. Using chemically-synthesized Ni NPs enables facile preparation of VACNF arrays with

Revealing the Interphase in Polymer Nanocomposites

March 16, 2011
Author(s)
Mauro Zammarano, Paul H. Maupin, Li Piin Sung, Jeffrey W. Gilman, Douglas M. Fox
Morphological characterization of polymer nanocomposites is a fundamental challenge that is complicated by multiple length scales. Here, we report a technique for high-throughput monitoring of interphase and dispersion in polymer nanocomposites based on
Displaying 551 - 575 of 882