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Displaying 4576 - 4600 of 74089

Quantum field theory for the chiral clock transition in one spatial dimension

May 3, 2021
Author(s)
Seth P. Whitsitt, Rhine Samajdar, Subir Sachdev
We describe the quantum phase transition in the N-state chiral clock model in spatial dimension d=1. With couplings chosen to preserve time-reversal and spatial inversion symmetries, such a model, is in the universality class of recent experimental studies

Report of the 104th National Conference on Weights and Measures

May 3, 2021
Author(s)
Yvonne Branden
The 104th Annual Meeting of the National Conference on Weights and Measures (NCWM) was held July 14 - 18, 2019, at the Hyatt Regency Milwaukee Hotel, Milwaukee, Wisconsin. The theme of the meeting was "Assuring Equity in the Marketplace: NIST and NCWM

Revision of the SNPforID 34-plex forensic ancestry test: Assay enhancements, standard reference sample genotypes and extended population studies

May 3, 2021
Author(s)
John Butler, Manuel Fondevila, Carla Santos, Ana Freire, Christopher Phillips, M Lareu, Peter Vallone
A revision of an established 34 SNP forensic ancestry test has been made by swapping the under- performing rs727811 component SNP with the highly informative rs3827760 that shows a near-fixed East Asian specific allele. We collated SNP variability data for

Scaling of Mass and Force Using Electrical Metrology

May 3, 2021
Author(s)
Gordon Shaw
The impending redefinition of the International System of Units (SI) allows realization of the kilogram using electrical metrology. It can be shown that electrical metrology can also be used to scale mass using electrostatic forces. An approach to mass

Beyond Color: The New Carbon Ink

May 2, 2021
Author(s)
Ming Zheng, YuHuang Wang
For thousands of years, carbon ink has been used as a black color pigment for writing and painting purposes. However, recent discoveries of nanocarbon materials, including fullerenes, carbon nanotubes, graphene, and their various derivative forms, together

Orientational ordering within semiconducting polymer fibrils

May 2, 2021
Author(s)
Subhrangsu Mukherjee, Eliot Gann, Masrur M. Nahid, Terry McAfee, Andrew Herzing, Dean DeLongchamp, Harald W. Ade
Due to a general paucity of suitable characterization methods, the internal orientational ordering of polymer fibrils has rarely been measured despite its importance particularly for semi-conducting polymers. An emerging tool with sensitivity to bond

Distributed fiber optic measurements of strain and temperature in long-span composite floor beams with simple shear connections subject to compartment fires

May 1, 2021
Author(s)
Yanping Zhu, Matthew Klegseth, Yi Bao, Matthew Hoehler, Lisa Choe, Genda Chen
This study explores an instrumentation strategy using distributed fiber optic sensors to measure strain and temperature through the concrete volume in large-scale structures. Single-mode optical fibers were deployed in three 12.8 m long steel and concrete

Residential net-zero energy buildings: Review and perspective

May 1, 2021
Author(s)
Wei Wu, Harrison Skye
Advancements in residential net-zero energy buildings (NZEBs) could significantly reduce energy use and greenhouse gas emissions. NZEB design considerations broadly categorize into energy infrastructure connections, renewable energy sources, and energy

Entanglement and purification transitions in non-Hermitian quantum mechanics

April 30, 2021
Author(s)
Michael Gullans, Sarang Gopalakrishnan
A quantum system subject to continuous measurement and post-selection evolves according to a non- Hermitian Hamiltonian. We show that, as one increases the rate of post-selection, this non- Hermitian Hamiltonian can undergo a spectral phase transition. On

Identifications of extreme ultraviolet spectra of Br-like to Ni-like neodymium ions using an electronbeam ion trap

April 30, 2021
Author(s)
C. Suzuki, Dipti Goyal, Y. Yang, A. Gall, Roshani Silwal, S. Sanders, Aung S. Naing, Joseph N. Tan, Endre A. Takacs, Yuri Ralchenko
Charge-resolved extreme ultraviolet spectra of open N-shell neodymium (Nd) ions have been recorded in an electron beam ion trap facility at the National Institute of Standards and Technology. The measurements have been performed for nominal electron beam

A Controlled Vocabulary and Metadata Schema for Materials Science Data Discovery

April 29, 2021
Author(s)
Andrea M. Medina-Smith, Chandler Becker, Raymond L. Plante, Laura Bartolo, Alden A. Dima, James A. Warren, Robert Hanisch
The International Materials Resource Registries (IMRR) working group of the Research Data Alliance (RDA) was created to spur initial development of a federated registry system to allow for easier discovery and access to materials data. As part of this

Catalyst Enabled in Situ Linkage Reduction in Imine Covalent Organic Frameworks

April 29, 2021
Author(s)
Jiyun Hu, Federica Zanca, Gregory McManus, Isabella Riha, Huong Giang Nguyen, William Shirley, Collin Borcik, Benjamin Wylie, Mourad Benamara, Roger van Zee, Peyman Moghadam, M. Hassan Beyzavi
New linkages for covalent organic frameworks (COFs) have been continuously pursued by chemists as it serves as the structure and property foundation for the materials. Developing new reaction types or modifying known linkages have been the only two methods

Compact Thermal Actuation by Water and Flexible Hydrophobic Nanopore

April 29, 2021
Author(s)
Miroslaw Chorazewski
Efficient and compact energy conversion is at the heart of sustainable development of humanity. In this work it is demonstrated that hydrophobic flexible nanoporous materials can be used for thermal-to-mechanical energy conversion when coupled with water

Guidance for NIST Staff on Using Inclusive Language in Documentary Standards

April 29, 2021
Author(s)
Kathryn Miller, David F. Alderman, Lisa Carnahan, Lily Chen, James Foti, Barbara L. Goldstein, Michael Hogan, Jennifer Marshall, Karen Reczek, Nathalie Rioux, Mary Frances Theofanos, David A. Wollman
This document provides guidance to NIST staff regarding the use of inclusive language in documentary standards and documents which support the realization and dissemination of physical standards; Standards Developing Organizations' (SDOs) policies and
Displaying 4576 - 4600 of 74089