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Search Publications

NIST Authors in Bold

Displaying 6576 - 6600 of 73727

Quasi-Deterministic Channel Propagation Model for an Urban Environment at 28 GHz

April 16, 2021
Author(s)
Neeraj Varshney, Jian Wang, Chiehping Lai, Camillo Gentile
We reduced parameters of the Quasi-Deterministic channel propagation model, recently adopted by the IEEE 802.11ay task group for next-generation Wi-Fi at millimeter-wave, from measurements collected in an urban environment with our 28 GHz directional

Characterization and Absolute Calibration of an AERONET-OC Radiometer

April 15, 2021
Author(s)
B. Carol Johnson, Giuseppe Zibordi, Steven W. Brown, Michael Feinholz, Mikhail Sorokin, Ilya Slutsker, John T. Woodward IV, Howard Yoon
The Ocean Color component of the global Aerosol Robotic Network (AERONET-OC) utilizes CE-318 sun photometers modified for above-water radiometry from fixed structures such as oil rigs, lighthouses, and service platforms. Primarily, AERONET-OC measurements

Cluster Morphology of Colloidal Systems with Competing Interactions

April 15, 2021
Author(s)
Nestor E. Valadez-Perez, Yun Liu, Ramon Castaneda-Priego
Reversible aggregation of purely short-ranged attractive colloidal particles leads to the formation of clusters with a fractal dimension that only depends on the second virial coefficient. The addition of a long-ranged repulsion to the potential modifies

Detection, counting and characterization of nanoplastics in marine bioindicators: a proof of principle study

April 15, 2021
Author(s)
Jeremie Parot, Andrea Valsesia, Jessica Ponti, Dora Mehn, Rita Marino, Daniela Melillo, Samantha Facchetti, Shinichiro N. Muramoto, R Verkouteren, Vincent Hackley, Pascal Colpo
Plastic particulates in the environment pose an increasing concern for regulatory bodies due to their potential risk to higher organisms (including humans) as they enter the food chain. Nanoplastics (pNP) (defined here as smaller than 1 µm) are

Neutron Spin Rotation Measurements

April 15, 2021
Author(s)
Jeffrey S. Nico, Shannon Hoogerheide, Hans Pieter Mumm, Murad Sarsour, J Amadio, Eamon Anderson, Libertad Barron-Palos, Bret Crawford, Chris Crawford, D. Esposito, Walter Fox, I Francis, J Fry, Chris Haddock, Adam Holley, Kirill Korsak, J Lieers, S Magers, M. Maldonado-Velazquez, D Mayorov, T Okudaira, C Paudel, S Santra, H.M. Shimizu, William M. Snow, A. Sprow, K. Steen, H E. Swanson, John Vanderwerp, P. A. Yergeau
The neutron spin rotation (NSR) collaboration used parity-violating spin rotation of transversely polarized neutrons transmitted through a 0.5 m liquid helium target to constrain weak coupling constants between nucleons. While consistent with theoretical

Quantum Phase Transitions in a Quasi-One-Dimensional Ising Quantum Magnet in Transverse Fields

April 15, 2021
Author(s)
Xiaowen Zhang, Zheng He, Yiqing Hao, Yao Shen, Shoudong Shen, Yu Feng, Guangyong Xu, Nicholas Butch, Goran J. Nilsen, Wenbin Wang, Jun Zhao
We report neutron scattering and thermodynamic measurements of the quasi-one-dimensional Ising magnet SrCo 2V 2O 8 under transverse fields along the tetragonal a/b direction. Our experiments reveal a Neel-type magnetic order in zero field, which

A Comprehensive Analysis on Multicast and Unicast Performance and Selection

April 14, 2021
Author(s)
Chen Shen, Chunmei Liu, Richard A. Rouil
Multicast transmission has long been studied along with its evolved standards, but few work provides comprehensive comparisons to Long Term Evolution (LTE) unicast transmissions. With focus on LTE Multicast Broadcast Single Frequency Network (MBSFN)

A Standard System Phantom for Magnetic Resonance Imaging

April 13, 2021
Author(s)
Maureen Ainslie, Michael A. Boss, Cecil Charles, Laurence Clarke, Jeffrey L. Evelhoch, Paul Finn, Derek L. Hill, Kathryn Keenan, Guoying Liu, Karl Stupic, Chun Yuan, Michele Martin, Maureen Ainslie, Nikki Rentz
A standard MRI system phantom has been designed and fabricated to assess scanner performance, scanner stability, scanner inter-comparability and accuracy of quantitative relaxation time imaging. The phantom is unique in having SI-traceability, a high level

Broadband generation of perfect Poincare beams via dielectric spin-multiplexed metasurface

April 13, 2021
Author(s)
Mingze Liu, Pengcheng Huo, Wenqi Zhu, Cheng Zhang, Si Zhang, Maowen Song, Song Zhang, Qianwei Zhou, Lu Chen, Henri Lezec, Amit Agrawal, Yanqing Lu, Ting Xu
Poincaré beam, which describes the space-variant polarization of a light beam carrying spin angular momentum (SAM) and orbital angular momentum (OAM), plays an important role in various optical applications. Since the radius of a Poincaré beam depends on

Implementing a Registry Federation for Materials Science Data Discovery

April 13, 2021
Author(s)
Raymond L. Plante, Chandler Becker, Andrea M. Medina-Smith, Kevin G. Brady, Alden A. Dima, Benjamin J. Long, Laura M. Bartolo, Robert Hanisch
As a result of a number of national initiatives, we are seeing rapid growth in the data important to materials science that are available over the web. Consequently, it is becoming increasingly difficult for researchers to learn what data are available and

Magnetic Particle Self-Assembly at Functionalized Interfaces

April 13, 2021
Author(s)
Apurve Saini, Katharina Theis-Brohl, Alexandros Koutsioubas, Kathryn L. Krycka, Julie Borchers, Max Wolff
We study the assembly of magnetite nanoparticles in water-based ferrofluids in wetting layers close to silicon substrates with different functionalization without and with an out-of-plane magnetic field. For particles of nominal sizes 5 nm, 15 nm and 25 nm

Role of low molecular weight polymers on the dynamics of silicon anodes during casting

April 13, 2021
Author(s)
Mary Burdette, Beth Armstrong, Ryan Murphy, Luke Heroux, Mathieu Doucet, Stephen Trask, Alexander Rogers, Gabriel Veith
This work probes the slurry architecture of a high silicon content electrode slurry with and without low molecular weight polymeric dispersants as a function of shear rate to mimic electrode casting conditions for poly(acrylic acid) (PAA) and lithium

Systematic Merging of Nonfullerene Acceptor p-Extension and Tetrafluorination Strategies Affords Polymer Solar Cells with > 16% Efficiency

April 13, 2021
Author(s)
Subhrangsu Mukherjee, Dean DeLongchamp, Guoping Li, Xiaohua Zhang, Leighton Jones, Joaquin Alzola, Liang-Wen Feng, Weigang Zhu, Charlotte Stern, Junsheng Yu, Vinod K. Sangwan, Kevin L. Kohlstedt, Michael R. Wasielewski, Mark C. Hersam, George C. Schatz, Antonio Facchetti, Tobin Marks
The end-capping group (EG) is the essential electron-withdrawing component of nonfullerene acceptors (NFAs) in bulk heterojunction (BHJ) organic solar cells (OSCs). To systematically probe the impact of two frequent EG functionalization strategies, π

Anisotropic resonant x-ray diffraction of a conjugated polymer at the sulfur K-edge

April 12, 2021
Author(s)
Eliot Gann, Christopher McNeill, Guillaume Freychet
The planar, aromatic nature of the backbone of conjugated polymers endow them with anisotropic properties. Here we show that the resonant x-ray diffraction of a sulfur containing semicrystalline conjugated polymer at the sulfur K-edge is highly anisotropic

Certification of Standard Reference Material(R) 2686b Portland Cement Clinker

April 12, 2021
Author(s)
N. Alan Heckert, Laura Mundy, Paul E. Stutzman
A new Standard Reference Material® (SRM) for portland cement clinker has been produced for the Office of Standard Reference Materials at the National Institute of Standards and Technology (NIST). The SRM clinkers are intended for use in developing and

Challenge Design and Lessons Learned from the 2018 Differential Privacy Challenges

April 12, 2021
Author(s)
Diane Ridgeway, Mary Theofanos, Terese Manley, Christine Task
The push for open data has made a multitude of datasets available enabling researchers to analyze publicly available information using various statistical and machine learning methods in support of policy development. An area of increasing interest that is

Combinatorial Testing Metrics for Machine Learning

April 12, 2021
Author(s)
Erin Lanus, Laura Freeman, D. Richard Kuhn, Raghu N. Kacker
This short paper defines a combinatorial coverage metric for comparing machine learning (ML) data sets and proposes the differences between data sets as a function of combinatorial coverage. The paper illustrates its utility for evaluating and predicting
Displaying 6576 - 6600 of 73727
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