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Search Publications

NIST Authors in Bold

Displaying 526 - 550 of 882

Gallium nitride nanowires achieve crystalline perfection

October 25, 2011
Author(s)
Kristine A. Bertness, Norman A. Sanford, John B. Schlager
A new method of growing a common semiconductor provides an avenue for fabricating perfect crystals in a form that takes advantage of their unique optical, electrical, and mechanical properties.

Radiation-Induced Synthesis of Poly(vinylpyrrolidone) Nanogel

October 14, 2011
Author(s)
Jung-Chul An, Alia Weaver, Byungnam Kim, Aaron Barkatt, Dianne L. Poster, Wyatt N. Vreeland, Joseph Silverman, Mohamad Al-Sheikhly
Studies of the radiation-induced synthesis of poly(vinylpyrrolidone) (PVP) nanogels, intended to provide a basis for obtaining intra-molecular cross-linked products, which are more useful in drug delivery, show that a sharp change in the controlling

Impact of Porous Media Grain Size on the Transport of Multiwalled Carbon Nanotubes

September 28, 2011
Author(s)
Nikolai Mattison, Denis O'Carroll, R. K. Rowe, Elijah Petersen
Nanomaterials possess unique physical, electrical and chemical properties which make them attractive for use in a wide range of applications. Through their use and eventual disposal, nanomaterials may ultimately be released into the subsurface environment

Formation and transfer of GaAsN nanostructure layers

September 27, 2011
Author(s)
Christopher L. Soles, Hyun W. Ro, A. Wood, N. Estrada, B. Dick, Y. Wang, Micheal Thouless, Rachel Goldman
Nanostructured materials with ultra-small crystallites (approaching the exciton Bohr radius) embedded in a solid-state matrix have great potential for optoelectronic and energy-conversion applications owing to the possibility of invoking quantum effects

Prototype cantilevers for quantitative lateral force microscopy

September 27, 2011
Author(s)
Mark Reitsma, Richard S. Gates, Lawrence H. Friedman, Robert F. Cook
Prototype cantilevers that enable quantitative micro- to nano-scale surface force measurements using contact-mode atomic force microscopy (AFM) are presented. The “Hammerhead” cantilevers allow precise optical lever system calibrations for cantilever

The Role of Iron Redox State in the Genotoxicity of Ultrafine Superparamagnetic Iron Oxide Nanoparticles

September 21, 2011
Author(s)
Neenu Singh, Gareth J. Jenkins, Bryant C. Nelson, Bryce J. Marquis, Thierry G. Maffeis, Andy P. Brown, Paul M. Williams, Chris J. Wright, Shareen H. Doak
Ultrafine superparamagnetic iron oxide nanoparticles (USPION) hold great potential for revolutionising biomedical applications such as MRI, localised hyperthermia, and targeted drug delivery. Though evidence is increasing regarding the influence of

Rectangular Scale-Similar Etch Pits in Monocrystalline Diamond

September 15, 2011
Author(s)
Craig D. McGray, Richard A. Allen, Marc J. Cangemi, Jon C. Geist
Etching of monocrystalline diamond in oxygen and water vapor at 1100° C through small pores in a silicon nitride film produced smooth-walled rectangular cavities. The cavities were imaged by electron microscope and measured by interferometric microscopy

Selective Oxidation of Glycerol by Highly Active Bimetallic Catalysts at Ambient Temperature under Base Free Conditions

August 24, 2011
Author(s)
Andrew A. Herzing, Gemma L. Brett, Peter Miedziak, Nikolaos Dimitratos, Meenakshisundaram Sankar, Marco Conte, Jose A. Lopez-Sanchez, David W. Knight, Stuart H. Taylor, Graham J. Hutchings, Qian He, Christopher J. Kiely
AuPt or AuPd nanoparticles when supported on Mg(OH)2 are highly active for the selective oxidation of glycerol under base-free conditions at ambient temperatures. When bimetallic particles with the appropriate composition are prepared, catalysts with a

Potassium Induced Charge Transfer Effects in OPE-based Molecular Layers

August 11, 2011
Author(s)
Steven W. Robey, Gregory J. Dutton
The impact of potassium (K) addition on the electronic structure of oligo- (phenylene ethynylene) (OPE) and –NO2 substituted OPE (NO2-OPE) self-assembled monolayers was examined using ultraviolet photoemission. Addition below 0.5 K/molecule produced rigid

GaN Nanowires Grown by Molecular Beam Epitaxy

August 1, 2011
Author(s)
Kristine A. Bertness, Norman A. Sanford, Albert Davydov
The unique properties of GaN nanowires grown by molecular beam epitaxy are reviewed. These properties include the absence of residual strain, exclusion of most extended defects, long photoluminescence lifetime, low surface recombination velocity,and high

Trapping and Release of Citrate-Capped Gold Nanoparticles

August 1, 2011
Author(s)
Darwin R. Reyes-Hernandez, Geraldine I. Mijares, Brian J. Nablo, Kimberly A. Briggman, Michael Gaitan
An electrical method to trap and release charged gold nanoparticles on and from the surface of alkanethiol self-assembled-monolayer (SAM) modified gold electrodes is presented. Gold nanoparticle (GNP) coated electrodes were formed by immersing amine

Lithography and Chemical Modeling of Acid Amplfiers for Use in EUV Photoresists

July 28, 2011
Author(s)
Kirstin Kruger, craig higgins, Gregg M. Gallatin, Robert Brainard
We postulate that the best way to simultaneously improve resolution, line edge roughness (LER), and sensitivity all in EUV resists is to increase the number of acid molecules generated per absorbed photon. In previous work, we showed that acid amplifiers

A circular dielectric grating for vertical extraction of single quantum dot emission

July 25, 2011
Author(s)
Marcelo I. Davanco, Matthew T. Rakher, Dieter Schuh, Antonio Badolato, Kartik A. Srinivasan
We demonstrate a suspended circular grating composed of partially etched annular trenches in a thin GaAs membrane, designed for e±cient and moderately broadband ( approx. 5 nm) extraction of emission from single InAs quantum dots. Simulations indicate that

Highly Selective GaN-nanowire/TiO2-nanocluser Hybrid Sensors for Detection of Benzene and Related Environment Pollutants

July 22, 2011
Author(s)
Geetha G. Aluri, Abhishek Motayed, Albert Davydov, Vladimir Oleshko, Kristine A. Bertness, Norman Sanford
Nanowire-nanocluster hybrid chemical sensors were realized by functionalizing gallium nitride (GaN) nanowires with titanium dioxide (TiO2) nanoclusters for selectively sensing benzene and other related aromatic compounds. Hybrid sensor devices were

Small fluctuations in epitaxial growth via conservative noise

July 7, 2011
Author(s)
Paul N. Patrone, Rongrong Wang, Dionisios Margetis
We study the combined effect of growth (material deposition from above) and nearest-neighbor entropic and force-dipole interactions in a stochastically perturbed system of N line defects (steps) on a vicinal crystal surface in 1+1 dimensions. First, we

Fate of nanoparticles during life cycle of polymer nanocomposites

July 6, 2011
Author(s)
Tinh Nguyen, Bastien T. Pellegrin, Coralie Bernard, Xiaohong Gu, Justin M. Gorham, Paul E. Stutzman, Deborah S. Jacobs, Walter E. Byrd, John W. Hettenhouser, Joannie W. Chin
Nanoparticles are increasingly used in consumer and structural polymeric products to enhance a variety of properties. Under the influences of environmental factors (e.g., ultraviolet, moisture, temperature) and mechanical actions (e.g., scratching
Displaying 526 - 550 of 882