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Search Publications

NIST Authors in Bold

Displaying 1251 - 1275 of 2606

Spherical indentation testing of poroelastic relaxations in thin hydrogel layers

December 16, 2011
Author(s)
Edwin Chan, Yuhang Hu, Peter M. Johnson, Zhigang Suo, Christopher Stafford
In this work, we present the Poroelastic Relaxation Indentation (PRI) testing approach for quantifying the mechanical and transport properties of thin layers of poly(ethylene glycol) hydrogel materials with thicknesses on the order of 200 m. Specifically

Seafood - Good Quantity Control Practices

December 15, 2011
Author(s)
David A. Sefcik
Webinar will identify the 4 primary components of a packaging system and help stakeholders know and recognize the 12 good quantity control practices, as outlined in HB 130. It will also teach them the criteria for evaluating their suppliers quantity

Report of the 96th National Conference on Weights and Measures (2011) SP1125

December 13, 2011
Author(s)
Linda D. Crown, Tina G. Butcher, Steven E. Cook, Richard A. Harshman, Lisa Warfield, David A. Sefcik
The 96th Annual Meeting of the National Conference on Weights and Measures (NCWM) was held July 17 to 21, 2011, at the Holiday Inn Downtown at the Park, Missoula, Montana. The theme of the meeting was Educating Today for Tomorrow. Reports by the NCWM Board

Three-dimensional Nanometrology with TSOM Optical Method

December 10, 2011
Author(s)
Ravikiran Attota
Through-focus scanning optical microscopy (TSOM) is a new metrology method that achieves 3D nanoscale measurement sensitivity using conventional optical microscopes; measurement sensitivities are comparable to what is typical when using scatterometry

Towards realization of a large-area, LED-based solar simulator

November 27, 2011
Author(s)
Behrang H. Hamadani, Kangbin Chua, John F. Roller, Howard W. Yoon, Brian P. Dougherty
LED-based solar simulators have shown great promise as alternative light sources for indoor testing of PV cells as compared to their traditional counterparts. However, large-area uniform illumination more suitable for larger cells and module measurements

TSOM Method for Nanoelectronics Dimensional Metrology

November 18, 2011
Author(s)
Ravikiran Attota
Through-focus scanning optical microscopy (TSOM) is a relatively new method that transforms conventional optical microscopes into truly three-dimensional metrology tools for nanoscale to microscale dimensional analysis. TSOM achieves this by acquiring and

NON-CONTACT DIMENSIONAL MEASUREMENTS OF BIPOLAR FUEL CELL PLATES

November 15, 2011
Author(s)
Balasubramanian Muralikrishnan, Wei Ren, Dennis S. Everett, Eric S. Stanfield, Theodore D. Doiron
Non-contact dimensional measurement of fuel cell plates is critical to the eventual rapid manufacture by supporting in-process measurement and control. This need has been identified by the Department of Energy’s Hydrogen Program, and by numerous

Manipulating Particle Trajectories with Phase-control in Surface Acoustic Wave Microfluidics

November 14, 2011
Author(s)
Nathan D. Orloff, Jaclyn R. Dennis, Marco Cecchini, Ethan Schonbrun, Eduard Rocas, Yu Y. Wang, David R. Novotny, Raymond W. Simmonds, John M. Moreland, Ichiro Takeuchi, James C. Booth
We present a 91 MHz surface acoustic wave resonator with integrated microfluidics that includes a flow focus, an expansion region, and a binning region. We demonstrate the ability to change the position of the acoustic nodes by varying the electronics

Quantum-based Voltage Waveform Synthesis

November 11, 2011
Author(s)
Samuel P. Benz
More than a decade of research and development was required to practically exploit the quantum behavior of superconducting Josephson junctions for ac applications. Sine waves and arbitrary waveforms had to be synthesized with sufficiently large voltage

Verification of Noise-Parameter Measurements and Uncertainties

November 1, 2011
Author(s)
James P. Randa, Dazhen Gu, Dave K. Walker
We propose and implement verification methods for measurements of noise parameters of amplifiers and transistors. Because the verification rests on the comparison of different measurement results, it also serves as a test of the uncertainties. The

November 2011 SRM Spotlight

October 24, 2011
Author(s)
Regina R. Montgomery
The SRM Spotlight is a newsletter published by the Measurement Services Division for users of NIST standard reference materials. The Spotlight announces new reference materials and provides information about their use. In addition, this newsletter contains

Determination of Moisture Content of Single-Wall Carbon Nanotubes

October 17, 2011
Author(s)
Rolf L. Zeisler, Rabia Oflaz, Ralph E. Sturgeon, Rick L. Paul, Brian E. Lang, Jeffrey A. Fagan, Joseph W. Lam, Anthony Windust, P Grinberg, Benoit Simard, Christopher T. Kingston
Several techniques were evaluated for the establishment of reliable water/moisture content of single-wall carbon nanotubes. Karl Fischer titration (KF) provides for a direct measure of the water content and was used for benchmarking against results

Carbon nanotube arrays for absolute IR and THz radiometry

October 2, 2011
Author(s)
John H. Lehman, Kerry N. Betz, Erich N. Grossman
We have assembled and evaluated a novel electrically calibrated thermopile having an array of 1.5 mm long multiwalled carbon nanotubes as the radiation absorber. We find very low reflectance at the 390 υm laser wavelength and excellent agreement between

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

Tare Verification - Ensuring the Accuracy of Tare

September 26, 2011
Author(s)
David A. Sefcik
Article for Weights and Measures Division "Connections" newsletter. Article discusses a suggested procedure for weights and measures officials to verify the accuracy of tare being used by the retailer before an official inspection is done.

Block copolymer photonic gel for mechanochromic sensing

September 19, 2011
Author(s)
Edwin Chan, Joseph J. Walish, Edwin L. Thomas, Christopher Stafford
In this work, we describe a strategy based on mechanochromic sensing, the coupling between mechanical and optical properties, of a block copolymer photonic gel. Although this phenomena has been observed in many materials, we demonstrate this concept for

Extending single-photon optimized superconducting transition edge sensors beyond the single-photon counting regime

September 19, 2011
Author(s)
Thomas Gerrits, Brice R. Calkins, Nathan A. Tomlin, Adriana E. Lita, Alan L. Migdall, Sae Woo Nam, Richard P. Mirin
Photon number resolving transition-edge sensors (TES) are the cutting-edge enabling technology for high quantum efficiency photon number counting. The TES developed at NIST reliably show system detection efficiencies of more than 95%, and even approach 99%

Absolute high-power laser measurements with a flowing water power meter

September 18, 2011
Author(s)
Christopher L. Cromer, Xiaoyu X. Li, John H. Lehman, Marla L. Dowell
We describe a novel flowing water power meter (FWOPM) for high-power laser radiometry in the range of 50 W to 10 kW. The FWOPM has several design features; a rotating mirror oriented at 45° with respect to the incoming radiation, a conical light-trapping
Displaying 1251 - 1275 of 2606