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Search Publications by: Dave Holbrook (Fed)

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Displaying 26 - 44 of 44

Preparation and Measurement Methods for Studying Nanoparticle Aggregate Surface Chemistry

June 8, 2012
Author(s)
Christopher W. Szakal, James McCarthy, Andrew R. Konicek, Kacie Louis, Benjamin Yezer, Andrew A. Herzing, Robert Hamers, Richard D. Holbrook
Despite best efforts at controlling nanoparticle (NP) surface chemistries, the environment surrounding nanomaterials is always changing and can impart a permanent chemical memory. We present a set of preparation and measurement methods to be used as the

Copper oxide nanoparticle mediated DNA damage in terrestrial plant models

December 22, 2011
Author(s)
Bryant C. Nelson, Donald H. Atha, Elijah J. Petersen, Huanhua Wang, Danielle Cleveland, Richard D. Holbrook, Pawel Jaruga, M Miral Dizdar, Baoshan Xing
Engineered nanoparticles, due to their unique electrical, mechanical and catalytic properties, are presently found in many commercial products and will be intentionally or inadvertently released at increasing concentrations into the natural environment

Potential release pathways, environmental fate, and ecological risks of carbon nanotubes

October 11, 2011
Author(s)
Elijah J. Petersen, Andrew Whelton, Liwen Zhang, Qingguo Huang, Nasir M. Uddin, Nikolai Mattison, Denis O'Carroll, Theodore Henry, Tinh Nguyen, Richard D. Holbrook, Kai Chen
Carbon nanotubes are currently being used in a number of consumer products, and exponentially higher production masses and a broader range of applications are expected in future years. However, the data on the environmental release pathways, environmental

Association of Quantum dot nanoparticles with Pseudomonas aeruginosa biofilm

November 1, 2010
Author(s)
Jayne B. Morrow, Catalina Arango, Richard D. Holbrook
Quantum dots (QDs) of two different surface chemistries (carboxyl (COOH) and poly ethylene glycol (PEG) modified) were utilized to determine the impact of surface functionality on QD mobility and distribution in Pseudomonas aeruginosa PAO1 biofilms

Trophic Transfer of Nanoparticles in a Simplified Food Web

May 30, 2008
Author(s)
Richard D. Holbrook, Karen E. Murphy, Jayne B. Morrow, Kenneth D. Cole
Nanotechnological innovations depend largely on the unique chemical and physical properties of engineered nanomaterials. However, the same properties that make engineered nanomaterials attractive for numerous applications also contribute to their

Widefield Light Microscopy Method for High Resolution and Quantum Dot Spectral Studies

January 1, 2007
Author(s)
Cynthia J. Zeissler, Keana C. Scott, Richard D. Holbrook, Peter E. Barker, Yan Xiao
We are exploring methods to achieve 3D 200 nm resolution multispectral imaging with an ordinary inexpensive widefield microscope using incoherent white light sources and an electronically tunable filter. In this work, the capabilities were applied to

Quantum Dot Dissemination and Behavior in Bacterial Biofilms

May 7, 2006
Author(s)
Jayne B. Morrow, Richard D. Holbrook, Cynthia J. Zeissler
Quantum dots (QDs) are colloidal semiconductor nanocrystals that photoluminescence emission is proportional to the dot size and have been utilized in fluorescent imaging in biological systems. Biofilms are communities of microorganisms attached to surfaces

Direct Preparation of Particles From Liquid Suspension for ESEM or SEM Analysis

October 1, 2005
Author(s)
Scott A. Wight, Richard D. Holbrook
A simplified method for the preparation of particles from liquid suspensions has been developed. Particles are deposited directly on carbon planchets for rapid analysis by environmental scanning electron microscopy or by conventional scanning electron