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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
Katherine E. Sharpless, David L. Duewer, Katrice A. Lippa, Andrew L. Rukhin
Although nutraceuticals and functional foods seem to be ill-defined terms, both are often used to indicate a food that contains compounds providing benefits beyond basic nutrition, often with the expectation that these compounds are protective against
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
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
Compressed-liquid densities of 3-ethoxy-1,1,1,2,3,4,4,5,5,6,6,6-dodecafluoro-2-trifluoromethyl-hexane (C9F15H5O) have been measured with a vibrating U-tube densimeter. To closely examine the repeatability of the measurements as well as the thermal
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
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
Joshua B. Martin, Winnie K. Wong-Ng, Thierry Caillat, Ichiro Yonenaga, Martin L. Green
The Seebeck coefficient is the most widely measured property specific to thermoelectric materials. Presently, there is no consensus on measurement protocols and researchers employ a variety of techniques to measure the Seebeck coefficient. The
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
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
This paper describes pitfalls, issues, and methodology for measuring software performance. Ideally, measurement should be performed and reported in such a way that others will be able to reproduce the results in order to confirm their validity. We aim to
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
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
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
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
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
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
After a brief introduction, the Neutron Resonance Spin Echo (NRSE) principle is discussed classically in Sec. 2. In Sec. 3, two idealized 4-coil NRSE spectrometers are discussed (one using single π coil units and one using paired "bootstrap" coils), some
Measurement uncertainty has important economic consequences for calibration and inspection activities. In calibration reports, the magnitude of the uncertainty is often taken as an indication of the quality of the laboratory. In industrial measurements
Summary: The iPhone liquid crystal displays allows efficient and accurate calibration of an inexpensive array of handheld microscopes for measuring microscopic dynamic events over a large field of view. How does one build an inexpensive array of handheld
Stephan Schlamminger, Darine El Haddad, Frank C. Seifert, Leon S. Chao, David B. Newell, Richard L. Steiner, Jon R. Pratt
In the past two years measurements were performed with a watt balance at the National Institute of Standards and Technology (NIST) to determine the Planck constant. A detailed analysis of these measurements and their uncertainties led to a value of h=6.626
Linda D. Crown, Tina G. Butcher, Richard A. Harshman, David A. Sefcik, Lisa Warfield
The 98th Annual Meeting of the National Conference on Weights and Measures (NCWM) was held July 14 to 18, 2013, at the Seelbach Hilton Louisville, Louisville, Kentucky. The theme of the meeting was On the Path to Tomorrow. Reports by the NCWM Board of
This article, for publication in NIST OWM's Weights and Measures Connection newsletter, describes the requirements outlined in NIST Handbook 44 for addressing "special and unclassified equipment" in the commercial marketplace. The article provides guidance
The effects of weak magnetic fields on the biological production of reactive oxygen species (ROS) from intracellular superoxide (O2−) and extracellular hydrogen peroxide (H2O2) were investigated in vitro with rat pulmonary arterial smooth muscle cells