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The current status of experimental approaches to analyze the spin wave dynamics in ferromagnetic nanoscale structures is reviewed. Recent developments in frequency- and field swept spectroscopy to determine the resonant response of nanoscale ferromagnets
Fernando L. Podio, Dylan J. Yaga, Christofer J. McGinnis
The Computer Security Division of NIST/ITL supports the development of biometric conformance testing methodology standards and other conformity assessment efforts through active technical participation in the development of these standards and the
Traceability of interferometric form measurements requires characterization of the reference wavefront. We investigate absolute tests for spherical surfaces where the form errors of both reference and test surface are estimated by minimizing the difference
Compressed-liquid densities and ambient pressure densities and speeds of sound of four biomass-derived fuels have been measured. The compressed-liquid measurements were made from 270 K to 470 K, and 0.5 MPa to 50 MPa. The ambient pressure measurements were
Andrew J. Slifka, Elizabeth S. Drexler, Neha N. Rustagi, Damian S. Lauria, Joseph D. McColskey, Robert L. Amaro
Fatigue crack growth tests were conducted on two API 5L X52 pipeline steel alloys. One alloy was from a new linepipe that was installed for hydrogen service in 2011. The other alloy was from a vintage pipe that first saw natural gas service in 1964
The diameter variation and refractive index inhomogeneity of a fused silica sphere were measured with a frequency-shifting Fizeau interferometer in a four-surface configuration. The phase-shifting algorithms to analyze the interference signals for each
When measuring standard resistors at different ratios with a Direct Current Comparator (DCC) incorporating Current Range Extenders (CREs) how do you know the value measured is correct and how can you evaluate the measurement uncertainty? This paper will
Using finite element analysis, we have developed a metrology simulation to model errors in the measurement of the Seebeck coefficient. This physical parameter is the constant of proportionality relating the electric potential that is generated across a
The National Institute of Standards, Office of Weights and Measures has been working the last few years toward compliance with several educational standards in support of our training program for the legal metrology and laboratory metrology community. By
Cynthia J. Zeissler, Lawrence Forsley, Richard M. Lindstrom, Sean Newsome, Adrean Kirk, P.A. Mosier-Boss
A nondestructive analytical method based on autoradiography and gamma spectrometry was developed to perform activity distribution analysis for particulate samples. This was applied to aerosols collected in Fukushima Japan, 40 km north of the Daiichi
Accurate cantilever spring constants are important in atomic force microscopy in both control of sensitive imaging and to provide correct nanomechanical property measurements. Conventional atomic force microscope (AFM) spring constant calibration
David L. Duewer, Hugo H. Gasca-Aragon, Katrice A. Lippa, Blaza Toman
This document provides the tedious mathematical details for OAWG Track B Key Comparisons that is, this document presents and discusses the statistical approaches involved in the design of Track B studies and analysis of the resulting data. This
David L. Duewer, Hugo H. Gasca-Aragon, Katrice A. Lippa, Blaza Toman
The analysis of higher-order value-assigned materials (HOVAMs) such as certified reference materials (CRMs) and value-assigned proficiency testing materials can help assess the equivalence of chemical measurement processes. When two or more such materials
Hongliang Shi, Hai-Jun Su, Nicholas Dagalakis, John A. Kramar
This paper covers the kinematic modeling of a flexure-based, hexapod nanopositioner and a new method of calibration for this type of nanopositioner. This six degrees of freedom tri-stage nanopositioner can generate small displacement, high-resolution
We calculated the eigenvalues of the radially-symmetric acoustic modes of a gas-filled, spherical cavity to order (δ T/a) 2, where δ T is the thickness of the thermal boundary layer and a is the radius of the cavity. Our results are consistent with high
Jeremy A. Marvel, Marek Franaszek, Jessica Wilson, Tsai Hong Hong
Low-cost 3D depth and range sensors are steadily becoming more widely available, affordable, and thus popular for robotics enthusiasts. As basic research tools, however, their accuracy and performance are relatively unknown. In this paper, we describe a
Daniel S. Hussey, David L. Jacobson, Richard Fu, Ugur Pasaogullari, Takeshi Shiomi, Yuichiro Tabuchi
We re-investigate our previously studied water transport phenomena under nonisothermal conditions by measuring the through-plane liquid water distribution across PEFC components with the state-of-the-art high-resolution neutron radiography. A corrective
Tinh Nguyen, Bastien T. Pellegrin, Coralie Bernard, Savelas A. Rabb, Paul E. Stutzman, Justin M. Gorham, Xiaohong Gu, Lee L. Yu, Joannie W. Chin
Nanofillers are increasingly used for enhancing multiple properties of polymeric materials in many applications. However, polymers are susceptible to photodegradation by solar ultraviolet (UV) radiation Therefore, nanofillers in a polymer nanocomposite
Thermogravimetric analysis with an SC-cut quartz crystal microbalance (QCM) were demonstrated at temperatures in the range from 20 C to 450 C. A measurement system was built around a crystal sensor head that was mounted in a small tube furnace. Changes in
A series of three Hydrogen in Titanium Alloy Standard Reference Materials (SRMs 2452, 2453, and 2454) were prepared with hydrogen mass fractions bracketing the hydrogen specification limit of 125 mg/kg. Commercial titanium alloy Ti6Al4V (6 % aluminum, 4 %
Nicholas Ritchie, Dale E. Newbury, Jeffrey M. Davis
The accuracy and precision of x-ray intensity measurements with an silicon drift detector (SDD) are compared with the same measurements performed on a wavelength spectrometer (WDS) for a variety of elements in a variety of materials. In cases of major (> 0
Ian M. Soboroff, Rodrygo Santos, Craig Macdonald, Richard McCreadie, Iadh Ounis
Blogs have recently emerged as a new open, rapidly evolving and reac- tive publishing medium on the Web. Rather than managed by a central entity, the content on the blogospherethe collection of all blogs on the Webis produced by millions of independent
John A. Horst, Curtis Brown, Robert Brown, Larry Maggiano, K Summerhays, Thomas R. Kramer
Much work has been done by standards organizations to model dimensional measurement information in digital formats, but the work done has revealed that standard digital formats from upstream processes are currently insufficient to enable the automatic
In this work, we describe a new imaging system, called a thermo-microscope, that can be used to visualize atmospheric pressure thermal desorption phenomena at high heating rates and frame rates. The system consists of a zoom lens coupled to a high-speed
Jin Chu Wu, Michael W. Halter, Raghu N. Kacker, John T. Elliott
Cell image segmentation (CIS) is critical for quantitative imaging in cytometric analyses. The data derived after segmentation can be used to infer cellular function. To evaluate CIS algorithms, first for dealing with comparisons of single cells treated as