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NIST Authors in Bold

Displaying 13201 - 13225 of 73927

Electromagnetic Scattering from Individual Crumpled Graphene Flakes: A Characteristic Modes Approach

September 14, 2017
Author(s)
Edward J. Garboczi, Jack F. Douglas, Luis Fernando Vargas Lara, Ahmed M. Hassan, Deb Chatterjee, Kalyan Durbhakula, Md Gaffar
Graphene flakes in real composites are rarely perfectly flat, and often exhibit complicated crumpled shapes. Therefore, the goal of this work was to quantify the electromagnetic scattering characteristics of individual crumpled graphene flakes with shapes

Time Information Broadcasting

September 14, 2017
Author(s)
John P. Lowe
The National Institute of Standards and Technology (NIST) operates radio station WWVB which broadcasts the official time of the United States. WWVB is a 60 kHz standard frequency broadcast emanating from Ft. Collins, Colorado since 1965. The broadcast

Behaviour of high-strength bolts at elevated temperatures under double-shear loading

September 13, 2017
Author(s)
Mina S. Seif, Jonathan M. Weigand, Rafaela Peixoto, Luiz Vieira
During fire events, connections in steel structures may be subjected to large unanticipated deformations and loads. Those fire effects can produce failures of connections, including local buckling of the connection zone, rupture of connection plates, shear

Black Box Measurement of System Noise in Integrated Wireless Receivers

September 13, 2017
Author(s)
Daniel G. Kuester, Duncan A. McGillivray, Sheryl M. Genco, Dazhen Gu
Tightly-integrated antennas and inaccessible radio frequency (RF) outputs are common barriers to measuring system noise in integrated wireless receive systems. We propose a solution centered on locating "SNR isoresponses" --- processed receiver outputs

Consistent View of Polypeptide Chain Expansion in Chemical Denaturants from Multiple Experimental Methods

September 13, 2017
Author(s)
Alessandro Borgia, Wenwei Zheng, Karin Buholzer, Madeleine Borgia, Anja Schuler, Hagen Hoffman, Andrea Sorrano, Daniel Nettels, Klaus Gast, Alexander Grishaev, Robert Best, Benjamin Schuler
There has been a long-standing controversy regarding the effect of chemical denaturants on the dimensions of unfolded and intrinsically disordered proteins: A wide range of experimental techniques suggest that polypeptide chains expand with increasing

Nanophotonic atomic force microscope transducers enable chemical composition and thermal conductivity measurements at the nanoscale

September 13, 2017
Author(s)
Jungseok Chae, Sangmin An, Georg Ramer, Vitalie Stavila, Glenn Holland, Yohan Yoon, Alec Talin, Mark Allendorf, Vladimir Aksyuk, Andrea Centrone
The atomic force microscope (AFM) offers a rich observation window on the nanoscale, yet many dynamic phenomena are too fast and too weak for direct detection, urging measurement innovation. Integrated cavity-optomechanics is revolutionizing

Non-Uniqueness in Dual-Energy CT with Beam Hardening

September 13, 2017
Author(s)
Zachary H. Levine
Purpose: The goal is to determine whether dual-energy computed tomography (CT) leads to a unique reconstruction into two basis materials. Methods and Materials: The beam hardening equation is simplified to the single voxel case. The simplified equation is

Autonomous Relocation of Mobile Base Stations in Emergency Scenarios

September 12, 2017
Author(s)
Kamran Sayrafian, Ladan Rabieekenari, John Baras
Limited access to communication services is one of the challenges that emergency personnel and first responders could face during environmental disasters or other emergencies. Networking infrastructure can breakdown during a catastrophe. At the same time

Calorimetric Determination of Enthalpies of Vaporization

September 12, 2017
Author(s)
Eugene Paulechka, Dzmitry H. Zaitsau
A review of calorimeters and experimental procedures used for measurement of enthalpies of vaporization for pure liquids is presented. The calorimetric approaches that are illustrated give an insight into direct determination of enthalpies of vaporization

Internal Pressure and Internal Energy of Saturated and Compressed Phases

September 12, 2017
Author(s)
Joe W. Magee, Ilmutdin Abdulagatov, Nikolai Polikhronidi, Rabiyat Batyrova
Following a critical review of the field, a comprehensive analysis is provided of the internal pressure of fluids and fluid mixtures and its determination in a wide range of temperatures and pressures. Further, the physical meaning is discussed of the

Using metagenomic methods to detect organismal contaminants in microbial materials.

September 12, 2017
Author(s)
Nathanael D. Olson, Justin M. Zook, Jayne B. Morrow, Nancy J. Lin
High sensitivity methods as next generation sequencing and PCR are adversely impacted by organismal and DNA contaminants. Current methods for detecting contaminants in microbial materials (genomic DNA and cultures) are not sensitive enough and require

Yang-Yang Critical Anomaly

September 12, 2017
Author(s)
Joe W. Magee, Ilmutdin Abdulagatov, Nikolai Polikhronidi, Rabiyat Batyrova
Following a critical review of related research, a method is described to evaluate the Yang-Yang critical anomaly strength function, , from experimental measurements of two-phase liquid ( ) and vapor ( ) isochoric heat capacities and liquid ( ) and vapor (

Formation of a crack-free, hybrid skin layer with tunable surface topography and improved gas permeation selectivity on elastomers using gel-liquid infiltration polymerization

September 11, 2017
Author(s)
Justin Gorham, Jason Killgore, Maryam Omidvar, Haiqing Lin, Frank W. DelRio, Lewis M. Cox, Zheng Zhang
Liquid-liquid interfacial polymerization (ll-IP) is conventionally used for manufacturing bulk polymers like nylon, as well as forming barrier layers for reverse osmosis membranes. In this work, we explore the use of gel-liquid infiltration polymerization

New measurement of the Boltzmann constant k by acoustic thermometry of helium-4 gas

September 11, 2017
Author(s)
Laurent Pitre, Fernando Sparasci, Michael R. Moldover, Cecile Guianvarch, Catherine Martin, Martin Himbert, Mark Plimmer, James B. Mehl, Giuliano Albo, Bo Gao, Lara Risegari
The SI unit of temperature will soon be redefined in terms of a fixed value of the Boltzmann constant k derived from an ensemble of measurements worldwide. We report on a new determination of k using acoustic thermometry of helium-4 gas in a 3-litre quasi
Displaying 13201 - 13225 of 73927
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