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NIST Authors in Bold

Displaying 876 - 900 of 2606

Multi-method analysis of multiwall carbon nanotube polymer nanocomposite samples after photodegradation

June 16, 2014
Author(s)
Elijah Petersen, Thomas F. Lam, Justin Gorham, Keana Scott, Chris Long, Renu Sharma, Li Piin Sung, James Alexander Liddle, Tinh Nguyen
Nanomaterials can be used as nanofillers to enhance the properties of polymeric materials. However, the effect of weathering on nanocomposites and the potential for nanomaterial release is not yet well understood. Multiple analytical methods are needed to

Characterizing a Noninsertable Directional Device Using the NIST Uncertainty Framework

June 6, 2014
Author(s)
Jeffrey A. Jargon, Dylan F. Williams, Paul D. Hale, Michael D. Janezic
We characterize and provide uncertainties for a noninsertable, directional device over a frequency range of 90 to 100 GHz using the NIST Microwave Uncertainty Framework in conjunction with a commercial vector network analyzer. Our device consists of a

Construction, Measurement, Shimming, and Performance of the NIST-4 Magnet System

June 6, 2014
Author(s)
Frank Seifert, Alireza Panna, Leon Chao, Bing Han, Shisong Li, Yusi A. Cao, Darine El Haddad, Stephan Schlamminger, Heeju Choi, Lori Haley
The magnet system is one of the key elements of a watt balance. For the new watt balance currently under construction at the National Institute of Standards and Technology a permanent magnet system was chosen. We describe the detailed construction of the

High Sensitivity Optomechanical Reference Accelerometer Over 10 kHz

June 5, 2014
Author(s)
Felipe Guzman, Lee M. Kumanchik, Jon R. Pratt, Jacob M. Taylor
We present an optically detected mechanical accelerometer that achieves a sensitivity of 100 ng/√Hz over a bandwidth of 10 kHz and is traceable. We have incorporated a Fabry-Perot fiber-optic micro-cavity that is currently capable of measuring the test

Large-area irradiance-mode spectral response measurements of solar cells by a light-emitting-diode- based integrating sphere source

May 30, 2014
Author(s)
Behrang H. Hamadani, John F. Roller, Andrew M. Shore, Brian P. Dougherty, Howard W. Yoon
An irradiance-mode absolute differential spectral response measurement system based on a light emitting diode (LED) array is described. The LEDs are coupled to an integrating sphere whose output irradiance is uniform to better than 2 % over an area of 160

Report of the 97th National Conference on Weights and Measures (2012)

May 30, 2014
Author(s)
Linda D. Crown, Tina G. Butcher, Richard A. Harshman, David A. Sefcik, Lisa Warfield
The 97th Annual Meeting of the National Conference on Weights and Measures (NCWM) was held July 15 through 19, 2012, at the Holiday Inn by the Bay, Portland, Maine. The theme of the meeting was "Taking Measure of Our Worth." Reports by the NCWM Board of

Acoustic Techniques for Measuring Transport Properties of Gases

May 22, 2014
Author(s)
Keith A. Gillis, Michael R. Moldover
We describe the principles, techniques, and performance of acoustic resonators used to measure the shear viscosity, the thermal conductivity, and the bulk viscosity in gases. We developed the Greenspan acoustic viscometer at NIST, where colleagues used it

Traceability for Millimeter and Submillimeter-Wave Power Measurements

May 21, 2014
Author(s)
Ronald A. Ginley
The need for traceable power measurements above 110 GHz is well established for use in communications, spectral line investigation, molecular particle signature identification, material property characterization and others. There have been incremental

Viscosity-ratio measurements with capillary viscometers

May 20, 2014
Author(s)
Robert F. Berg, Eric F. May, Michael R. Moldover
Viscosity-ratio measurements made with capillary viscometers exploit the accurate values of the viscosity of helium resulting from ab initio calculations. Accurate values of the argon-to-helium viscosity ratio are now used for primary acoustic thermometry

Control Fusion for Safe Multi-robot Coordination

May 9, 2014
Author(s)
Roger V. Bostelman, Jeremy A. Marvel
Future smart manufacturing systems will include more complex coordination of mobile manipulators (e.g., robot arms mounted on mobile bases). The National Institute of Standards and Technology, Performance of Collaborative Robot Systems Project has been

NIST Micronutrients Measurement Quality Assurance Program Winter, Spring, and Fall 1995 Comparability Studies: Results for Round Robins XXXIII, XXXIV, and XXXV Fat-Soluble Vitamins and Carotenoids in Human Serum and Round Robins 7 and 8 Ascorbic Acid in H

April 25, 2014
Author(s)
David L. Duewer, Margaret C. Kline, Katherine E. Sharpless, Jeanice M. Brown Thomas, Sam A. Margolis
The National Institute of Standards and Technology coordinates the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat- and water-soluble vitamins and carotenoids in human serum and plasma. This report describes

2013 ITRS Metrology Roadmap

April 15, 2014
Author(s)
Alain C. Diebold, Ndubuisi George Orji
In 2013 the ITRS Metrology Technical Working Group worked on updating the text and tables of the metrology chapter. New additions include a section on 3D nanometrology, a revised lithography metrology table, and an updated Interconnect section. The

Hydrogen Field Test Standard: Laboratory Performance

April 14, 2014
Author(s)
Jodie G. Pope, John D. Wright
NIST developed a prototype field test standard (FTS) that incorporates three test methods that could be used by state weights and measures inspectors to periodically test retail hydrogen dispensers, much as gasoline dispensers are tested today. The three

Recent Advances in Focused Ion Beam Technology and Applications

April 11, 2014
Author(s)
Nabil Bassim, Keana Scott, Lucille A. Giannuzzi
Focused ion beam (FIB) microscopes are extremely versatile and powerful instruments for materials research. These microscopes, when coupled in a system with a scanning electron microscope (SEM), offer the opportunity for novel sample imaging, sectioning

Terahertz Active and Passive Imaging

April 11, 2014
Author(s)
Erich N. Grossman, Joshua A. Gordon, David R. Novotny, Richard A. Chamberlin
We describe the results of bistatic scattering measurements covering 325-650 GHz on a series of wellcharacterized random rough test surfaces. These have implications for active THz imagers that use coherent sources for illumination. The mean scattered

10 nm Three-Dimensional CD-SEM Metrology

April 10, 2014
Author(s)
Andras Vladar, John S. Villarrubia, Bin Ming, Regis J. Kline, Jasmeet Chawla, Scott List, Michael T. Postek
The shape and dimensions of a challenging pattern have been measured using a model-based library scanning electron microscope (MBL SEM) technique. The sample consisted of a 4-line repeating pattern. Lines were narrow (10 nm), asymmetric (different edge
Displaying 876 - 900 of 2606