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James Cline, David R. Black, Donald Windover, Albert Henins
The laboratory X-ray powder diffractometer offers several virtues that have rendered it a principal characterization device providing critical data for a range of technical disciplines. A continuous suite of hkl reflections can be collected with a single
Dazhen Gu, James P. Randa, Robert L. Billinger, Dave K. Walker
We report a verification method for noise-temperature (NT) measurements on cryogenic low-noise amplifiers (LNAs) at liquid helium temperature. The method uses a comparison between the individual measurements of the LNA and an attenuator and the joint
We compare three methods of quantifying illumination efficiency (IE). The ratio IE describes the contribution of energy emitted from a blackbody target to the total energy measured at an antenna aperture in a free-space microwave calibration target
At the National Institute of Standards and Technology a new watt balance, NIST-4, is currently being designed. This apparatus will be used to realize the unit of mass after the redefinition of the SI has taken effect. In order to ensure smooth operation
Yvonne B. Gerbig, Chris A. Michaels, Aaron M. Forster, John W. Hettenhouser, Walter E. Byrd, Dylan J. Morris, Robert F. Cook
Instrumented indentation is a widely used technique to study the mechanical behavior of materials at small length scales and thus has been exploited in particular for metals, ceramics, glasses, and polymers. Mechanical tests of bulk materials, microscopic
David Bishop, Flavio Pardo, Cris Bolle, Randy Giles, Vladimir Aksyuk
Over the last decade or so a group of us, while working at Bell Labs, have been able to develop a large number of silicon micromachines for a wide range of applications. In this article, which is part of a special volume to celebrate the career of
Yoshihiro Nakashima, Michael A. Boss, Stephen E. Russek, John M. Moreland
We have developed a nuclear magnetic resonance (NMR) microcapillary probe for the detection of single magnetic microbeads. The geometry of the probe has been optimized so that the signal from the background water has a similar magnitude compared to the
Christopher W. Meyer, W Wyatt Miller, Dean C. Ripple, Gregory E. Scace
We provide here a detailed uncertainty budget for the new Hybrid Humidity Generator (HHG) that has been constructed at the National Institute of Standards and Technology (NIST). The HHG generates frost/dew points from 70 °C to +85 °C using calibration gas
D Vega-Maza, W. Wyatt Miller, Dean C. Ripple, Gregory E. Scace
We have constructed a new humidity generator that produces gas streams of known moisture content at temperatures from 85 °C to 200 °C, absolute pressures from 0.2 MPa to 1.6 MPa, and relative humidities from 10 % to 90 %. The generator produces a moist gas
We individually characterize and provide uncertainties for a pair of WR-8 rectangular waveguide-to-coplanar waveguide (CPW) probes over a frequency range of 90 to 140 GHz utilizing two methods implemented within the NIST Microwave Uncertainty Framework
Vyacheslav B. Podobedov, George P. Eppeldauer, Thomas C. Larason
Analysis of multiple factors affecting the uncertainty of the absolute spectral responsivity of optical radiation detectors is presented. This includes both the validation of the radiometric scale of the infrared reference detectors and the scale transfer
Historically, mechanical assembly was predicted to be the dominant application domain of industrial robots; yet assembly tasks are still primarily addressed by manual labor. New advances in force control (FC), machine vision, and robot dexterity are
Sung Kim, Christopher L. Holloway, Michael D. Janezic, Kendra L. Kumley, James R. Baker-Jarvis, Edward Kuester
We present a rectangular S-band waveguide having electromagnetic bandgap properties (stopbands) controlled with sheets of metafilms composed of ceramic particles, in which we present both analytic and experimental results. Metafilms composed of TiO("d)2
Christopher L. Soles, Hyun W. Ro, K. J. Alvine, Oleg Shpyrko, Yenling Dai, Alec Sandy, Suresh Narayanan
The surface dynamics of thin molten polystyrene films supported by nanoscale periodic silicon line-space gratings were investigated with X-ray photon correlation spectroscopy. Surface dynamics over these nanostructures exhibit high directional anisotropy
Tina Butcher, Linda D. Crown, Richard A. Harshman, Juana Williams
Handbook 44 was first printed in 1949, having been preceded by similar handbooks of various designations and in several forms. This 2013 edition was developed by the Committee on Specifications and Tolerances of the National Conference on Weights and
A feasibility study was performed to evaluate a novel method of accurately fatigue cracking steel plates to generate fatigue proposed fatigue crack reference standards. Fatigue cracks were introduced into low carbon steel reference plates in which the
Pavel Kabos, A Caprile, Coisson Marco, F Fiorillo, O M. Manu, E. S. Olivetti, M. A. Olariu, Pasquale Massimo, V. A. Scarlatache
Samples composed of a polymer matrix were loaded with different fractions from 0 to 30% of Fe oxide magnetic nanoparticles with an average size ranging from 50 to 25 nm. The permittivity and permeability of the composites were determined upon a very wide
In this paper, we present an optical imaging tool, the Overlay Imaging Aligner (OIA), developed to aid in the mechanical alignment of antenna components in the mm-wave and low-THz frequency regimes (50500 GHz) where the millimeter and sub millimeter
Bruce Ravel, J. R. Hester, V. A. Sole, M. Newville
A working group on data format standardization for X-ray Absorption Spectroscopy has recently formed under the auspices of International X-ray Absorption Society and the XAFS Commission of the IUCr. This group of beamline scientists and XAS ractitioners
This handbook compiles uniform laws and regulations developed by the Committee on Laws and Regulatiosn of the National Conference of Weights and Measures (NCWM). This editon contains amendments adopted by the NCWM at its Annual Meeting in 2012. It includes
This handbook has been prepared as a procedural guide for the compliance testing of net contents statements on packaged goods. Compliance testing of packaged goods is the determination of the conformance results of the packaging, distribution, and
David R. Novotny, Josh Gordon, Edwin J. Heilweil, Brian C. Stillwell, Jeffrey R. Guerrieri, Erich N. Grossman, Shu Z. Lo
Beginning the fall of 2012, NIST will be providing scattering measurements for other government agencies. We present performance results of a bi-directional scattering measurement system in the 200-500 GHz range. The goal is to provide dense-spectrum, bi
Josh Gordon, David R. Novotny, Jeffrey R. Guerrieri, Jason Coder, Michael Francis
The Antenna Metrology Lab at the National Institute of Standards and Technology in Boulder Colorado has developed a robotically controlled near-field pattern range for measuring antennas and quasi-optical components from 50 GHz to 500 GHz. This range is
Zhao Z. Deng, Alexander Smolyanitsky, Qunyang Li, Xi-Qiao Feng, Rachel J. Cannara
A negative friction coefficient is observed for graphite using atomic force microscopy. The magnitude of the friction coefficient increases with adhesion, which we control by exposing graphite to different conditions. We demonstrate that the negative