An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
All forms of microscopy are being pushed to the limit by nanotechnology. Hence, there is a relentless quest to achieve better and better resolution with various electron and ion microscopes and to monitor and maintain these instruments to achieve the best
A colloidal synthesis route was developed to produce face-centered cubic (fcc) copper (Cu) nanoparticles in the presence of the surfactants in an organic solvent under an argon environment. Various synthetic conditions have been explored to control the
Jason J. Gorman, Yong Sik Kim, Andras Vladar, Nicholas G. Dagalakis
A microscale nanoassembly system has been designed for the fabrication of nanodevices and in situ electromechanical characterisation of nanostructures. This system consists of four Microelectromechanical Systems(MEMS)-based nanomanipulators positioned
Lucile C. Teague, Behrang H. Hamadani, John E. Anthony, David J. Gundlach, James G. Kushmerick, Sanker Subramanian, Thomas Jackson, Curt A. Richter, Oana Jurchescu
We report scanning Kelvin probe microscopy (SKPM) of electrically biased difluoro bis(triethylsilylethynyl) anthradithiophene (diF-TESADT) organic thin film transistors. SKPM reveals the relationship between the diF-TESADT film structure and device
Robert A. Fletcher, Nathanael Briggs, Erin Ferguson, J Greg Gillen
Experiments were conducted to determine particle removal efficiencies from surfaces due to air jet impingement. We utilize monodisperse fluorescent polymer spheres ranging from 1 μm to 45 μm diameter distributed on polycarbonate surfaces and muslin cloth
Darwin R. Reyes-Hernandez, Geraldine I. Mijares, Kimberly A. Briggman, Jon C. Geist, Michael Gaitan
An electrical method to trap and release gold nanoparticles to and from the surface of alkanethiol-modified gold electrodes is presented. When a positive bias versus a Ag/AgCl reference electrode was applied to gold electrodes, negatively-charged gold
Critical Dimension Atomic Force Microscopy (CD-AFM) is a primary means to measure the geometric shapes of walls and trenches on the nanometer scale in laboratories supporting the electronic industry. As the widths of commercially available CD-AFM probes
The objective of this project was to calibrate a commercially available force feedback joystick that could be used for the control of a laser beam optical tweezers test-bed. A calibration box was built to hold the joystick and the load-cell. The joystick
Lam H. Yu, Nadine E. Gergel-Hackett, Christopher D. Zangmeister, Christina A. Hacker, Curt A. Richter, James G. Kushmerick
Abstract. Semiconductor-molecule-metal junctions consisting of alkanethiol mono- layers self-assembled on both p+ and n¡ type highly doped Si(111)wires contacted with a 10 ¹m Au wire in a crossed-wire geometry are examined. Low temperature transport
A three-dimensional Green's function for a material system containing general anisotropic and linearly elastic planar multilayers with interfacial membrane and flexural rigidities has been derived. The Stroh formalism and two-dimensional Fourier transforms
Ward L. Johnson, Sudook A. Kim, Zhandos Utegulov, B. T. Draine
Electric-field distributions in two-dimensional arrays of gold nanodisks on Si3N4 membranes are modeled, using the discrete-dipole approximation, as a function of nanodisk diameter (20 − 50 nm), height (10 − 100 nm), ratio of the array spacing to diameter
Gheorghe Stan, Sergiy Krylyuk, Albert Davydov, Mark D. Vaudin, Leonid A. Bendersky, Robert F. Cook
Nondestructive elastic property measurements have been performed on Te nanowires with diameters in the range 20 150 nm. By using contact resonance atomic force microscopy, the elastic indentation modulus perpendicular to the prismatic facets of the
Fundamental deflection behavior of an infinite two-dimensional graphene lattice subjected to a transverse point force has been analyzed using lattice statics and the continuum Green's functions. An analytic expression has been derived for the lattice
Research and development of nanotechnology, with applications ranging from smart materials to quantum computation to biolabs on a chip, has a high national priority. In this article we focus on the use of high performance computing an visualization for
Doo-In Kim, Jaroslaw Grobelny, Pradeep N. Namboodiri, Robert F. Cook
The origin of adhesion at nanoscale contacts in humid air is investigated by pull-off force measurements using atomic force microscopes in controlled environments from ultra-high vacuum through various humidity conditions to water. An equivalent work of
Brillouin-light-scattering spectra previously have been shown to provide information on acoustic modes of polymeric lines fabricated by nanoimprint lithography. Finite-element methods for modeling such modes are presented here. These methods provide a
Chemical images of the surfaces and the interiors of coatings of rapamycin in poly(lactic-co-glycolic acid) (PLGA) obtained by mass spectrometry and light scattering methods reveal a three dimensional picture of the chemical morphology of drug eluting
Cluster Secondary Ion Mass Spectrometry (cluster SIMS) employing an SF5+ polyatomic primary ion sputter source in conjunction with a Bi3+ analysis source was used to obtain 3-dimensional molecular information in polymeric-based drug eluting stent (DES)
Krishna Ramadurai, Christopher L. Cromer, Laurence A. Lewis, Katie Hurst, Anne Dillon, Roop Mahajan, John H. Lehman
Radiometry for the next generation of high-efficiency, high-power industrial lasers requires thermal management at optical power levels exceeding 10 kW. Laser damage and thermal transport present fundamental challenges for laser radiometry in support of
John Wason, William Gressick, J Wen, Jason J. Gorman, Nicholas Dagalakis
This paper describes the algorithm development and experimental results of a multi-probe micro-assembly system. The experimental testbed consists of two actuated probes, an actuated die stage, and vision feedback. The kinematics relationships for the
R M. Verkouteren, John G. Gillen, Jennifer R. Verkouteren, Robert A. Fletcher, Eric S. Windsor, Wayne Smith
Trace detection is a primary strategy for thwarting terrorism activities in the US and abroad. The development of effective reference materials and methods for this purpose relies on fundamental knowledge regarding the size, mass, morphologies, and
Eric Langlois, G. A. Shaw, J. A. Kramar, Jon R. Pratt, Donna C. Hurley
We describe a method to calibrate the spring constants of cantilevers used in atomic force microscopy (AFM) by means of a piezoresistive cantilever. Before use, the piezoresistive cantilever was calibrated with an absolute force standard, the NIST
Dianne L. Poster, John A. Small, Michael T. Postek
The National Nanotechnology Initiative (NNI) in its 2006 document, Environmental, Health, and Safety Research Needs for Engineered Nanoscale Materials (available at www.nano.gov), identifies standards and standard measurement protocols as a critical