U.S. flag

An official website of the United States government

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.

Search Publications

NIST Authors in Bold

Displaying 25101 - 25125 of 73697

A Human Urine Standard Reference Materials for Accurate Assessment of Arsenic Exposure

March 17, 2011
Author(s)
Lee L. Yu, Carl Verdon, William C. Davis, Gregory C. Turk, Kathleen Caldwell, Robert Jones, Brian Buckley, Ruimin Xie
Arsenic is a toxic element, and the toxicity of the element is dependent upon the molecular form it is in. Accurate assessments of arsenic exposure require the measurement of a complete panel of inorganic, organic, and metabolite As species in urine

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

Reorientational Dynamics of the Dodecahydro-Closo-Codecaborate Anion in Cs 2 B 12 H 12

March 17, 2011
Author(s)
Kristina Verdal, Terrence J. Udovic, John J. Rush, Ronald L. Cappelletti, Wei Zhou
Rapid reorientational motions of the B12H122- icosahedral anion, a key intermediate in borohydride dehydrogenation, are revealed by quasielastic neutron scattering (QENS) measurements of Cs2B12H12 between 430 K and 530 K. At 430 K, over the range of

An Introduction to the Good, the Bad, & the Ugly Face Recognition Challenge Problem

March 16, 2011
Author(s)
P J. Phillips, J. R. Beveridge, Bruce A. Draper, Geof H. Givens, Alice J. O'Toole, David Bolme, Joseph Dunlop, Yui M. Lui, Hassan A. Sahibzada, Samuel Weimer
The Good, the Bad, & the Ugly Face Challenge Problem was created to encourage the development of algorithms that are robust to recognition across changes that occur in still frontal faces. The Good, the Bad, & the Ugly consists of three partitions. The

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

Quantitative Subsurface Contact Resonance Force Microscopy of Model Polymer Nanocomposites

March 16, 2011
Author(s)
Jason P. Killgore, Jennifer Y. Kelly, Christopher M. Stafford, Michael J. Fasolka, Donna C. Hurley
We present experimental results on the use of quantitative contact resonance force microscopy (CR-FM) for mapping the planar location and depth of 50 nm silica nanoparticles buried beneath polystyrene films 30 nm to 165 nm thick. The presence of shallowly

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

H Atom Attack on Propene

March 15, 2011
Author(s)
Claudette M. Rosado-Reyes, Jeffrey A. Manion, Wing Tsang
The reaction of propene(CH3CH=CH2) with hydrogen atoms has been investigated in a heated single-pulsed shock tube at temperature between 929K-1212K and pressures of 1.7bar-3.4bar. Stable products from H atom addition and H abstraction have been identified

Confidence in VNA Measurements The ARFTG Measurement Comparison Program

March 14, 2011
Author(s)
Ronald A. Ginley
This paper describes the ARFTG scattering parameter Measurement Comparison Program (MCP) which is supported by NIST. The ARFTG MCP is designed specifically to allow users of vector network analyzers to compare their measurements to those of their peers

Magnetic Field Effect on the Static Antiferromagnetic Order and Spin Excitations in Underdoped Iron Arsenide Superconductor BaFe 1.92 Ni 0.08 As 2

March 14, 2011
Author(s)
Miaoyin Wang, Huiqian Luo, Meng Wang, Song Xue Chi, Jose Rodriguez Rivera, Deepak Singh, Sung Chang, Jeffrey W. Lynn, Pengcheng Dai
We use neutron scattering to study the magnetic field effect on the static antiferromagnetic (AF) order and low-energy spin excitations in the underdoped iron arsenide superconductor BaFe 1.92Ni 0.08As 2. At zero field, superconductivity that occurs below

Pressure Controlled Advanced Distillation Curve Analysis on Alternative Fuels

March 14, 2011
Author(s)
Bret Windom, Tara M. Lovestead, Thomas J. Bruno
Biodiesel fuel is an alternative fuel that can be derived from a number of renewable feedstocks including plant and vegetable oils, algae, animal fats, waste oils, etc. The fatty acid methyl ester (FAME) profile, and thus the resultant properties, of the

Technical Study of the Sofa Super Store Fire, South Carolina, June 18, 2007, Volume I

March 14, 2011
Author(s)
Nelson P. Bryner, Stephen P. Fuss, Bryan W. Klein, Anthony D. Putorti Jr.
A fire occurred on the evening of June 18, 2007, in the Sofa Super Store in Charleston, SC. NIST analyzed the fire ground, consulted with other experts, and performed computer simulations of fire growth alternatives. Based on these analyses, the following

When High-Quality Face Images Match Poorly

March 13, 2011
Author(s)
J. R. Beveridge, P. Jonathon Phillips, Geof H. Givens, Bruce A. Draper, Mohammad N. Teli, David Bolme
In face recognition, quality is typically thought of as a property of individual images, not image pairs. The implicit assumption is that high-quality images should be easy to match to each other, while low quality images should be hard to match. This

Demographic Effects on Estimates of Automatic Face Recognition Performance

March 11, 2011
Author(s)
Alice J. O'Toole, P. Jonathon Phillips, Xiaobo An, Joseph Dunlop
The intended applications of automatic face recognition systems include venues that vary widely in demographic diversity. Formal evaluations of algorithms do not commonly consider the effects of population diversity on performance. We document the effects
Displaying 25101 - 25125 of 73697
Was this page helpful?