Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications

NIST Authors in Bold

Displaying 1 - 25 of 1638

Core-hole potentials and related effects

January 12, 2022
Eric L. Shirley, Lars G. Pettersson, D. Prendergast
We consider the constrained-occupancy and (linear-response) self-consistent-field methods for screening of core-hole potentials that affect core excitation near-edge spectra. The methods are not exact, but each has distinct advantages and limitations. The

Revisiting a local, real-space approach to dielectric screening calculations

January 12, 2022
Eric L. Shirley, John Vinson
Various many-body perturbation theory techniques for calculating electron behavior rely on W, the screened Coulomb interaction. The screening requires complete knowledge of the dielectric response of the electronic system, and the delity of the calculated

NIST Outdoor Structure Separation Experiments (NOSSE): Preliminary Test Plan

January 10, 2022
Alexander Maranghides, Shonali Nazare, Eric Link, Matthew Bundy, Artur A. Chernovsky, Erik L. Johnsson, Kathryn Butler, Steven Hawks, Frank Bigelow, William (Ruddy) Mell, Anthony Bova, Derek McNamara, Tom MIlac, Daniel Gorham, Faraz Hedayati, Bob Raymer, Frank Frievalt, William Walton
The Structure Separation Project is a multi-level project to assess structure-to-structure fire spread in Wildland-Urban Interface (WUI) communities. The project is divided into three phases with each phase assessing radiant and convective heat exposures

Chiral Spin Bobbers in Exchange-Coupled Hard-Soft Magnetic Bilayers

January 6, 2022
X. H. Zhang, T. R. Gao, L. Fang, S. Fackler, Julie A. Borchers, Brian Kirby, Brian B. Maranville, S. E. Lofland, A. T. N'Diaye, E. Arenholz, A. Ullah, J. Cui, R. Skomski, Ichiro Takeuchi
The spin structure of exchange-coupled MnBi:Co-Fe bilayers is investigated by X-ray magnetic circular dichroism (XMCD), polarized neutron reflectometry (PNR), and micromagnetic simu-lations. The purpose of the present research is two-fold. First, the

Late Stage Domain Coarsening Dynamics of Lamellar Block Copolymers

January 4, 2022
Jack F. Douglas, Maninderjeet Singh, Wenjie Wu, Vinay Nuka, Joseph Strzalka, Alamgir Karim
Block copolymer (BCP) phase separation is an intriguing phenomenon whose dynamics can be expected to differ significantly from that of the polymer blends due to constraint of chain connectivity that limits the ultimate scale of phase separation and the

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

January 4, 2022
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

In situ absorption synchrotron measurements, predictive modeling, microstructural analysis, and scanning probe measurements of laser melted Ti-6Al-4V single tracks for additive manufacturing applications

December 29, 2021
Nicholas Derimow, Edwin Schwalbach, Jake Benzing, Jason Killgore, Aly Artusio-Glimpse, Nik Hrabe, Brian Simonds
In this work, the fundamental processing-structure-property (PSP) relationships that govern laser-based additive manufacturing were investigated with the Ti-6Al-4V alloy. X-ray synchrotron imaging carried out in conjunction with in-situ integrating sphere

Instrumented Charpy Tests at 77 K on 316L Stainless Steel Welded Plates

December 20, 2021
Enrico Lucon, Jake Benzing
In the framework of a collaborative project between ASME, NASA, and NIST, instrumented Charpy tests have been performed at liquid nitrogen temperature (77 K, or 196 °C) on specimens extracted from the center of four 316L welded stainless steel plates, each

Circular Economy in the High-Tech World Workshop Report

December 14, 2021
Martin L. Green, Kelsea Schumacher
The National Institute of Standards and Technology (NIST) held a Technical Workshop on January 27 and 28, 2021 to assess the state and challenges of a Circular Economy (CE) in the High-Tech World. Scientists, researchers, and program managers in the CE

Model for the Bipolar Amplification Effect

December 10, 2021
James Ashton, Stephen Moxim, Ashton Purcell, Patrick Lenahan, Jason Ryan
We present a model based on Fitzgerald-Grove surface recombination for the bipolar amplification effect (BAE) measurement, which is widely utilized in electrically detected magnetic resonance (EDMR) to measure reliability and performance-limiting interface

Computational scanning tunneling microscope image database

December 5, 2021
Kamal Choudhary, Kevin Garrity, Charles Camp, Sergei Kalinin, Rama Vasudevan, Maxim Ziatdinov, Francesca Tavazza
We introduce the systematic database of scanning tunneling microscope (STM) images obtained using density functional theory (DFT) for two-dimensional (2D) materials, calculated using the Tersoff-Hamann method. It currently contains data for 716 exfoliable

How Austenitic is a Martensitic Steel Produced by Laser Powder Bed Fusion? A Cautionary Tale

December 2, 2021
Fan Zhang, Mark R. Stoudt, Souzan Hammadi, Carelyn E. Campbell, Eric A. Lass, Maureen E. Williams
Accurate phase fraction analysis is an essential element of microstructural characterization of alloys and often serves as a basis to quantify effects such as heat treatment or mechanical deformation. Additive manufacturing (AM) of metals, due to the

Opportunities in electrically tunable 2D materials beyond graphene: Recent progress and future outlook

November 30, 2021
Tom Vincent, Jiayun liang, simrjit singh, eli castanon, xiaotian zhang, deep jariwala, olga kazakova, zakaria al-balushi, Amber McCreary
The interest in two-dimensional and layered materials continues to expand, driven by the compelling properties of individual atomic layers that can be stacked and/or twisted into synthetic heterostructures. The plethora of electronic properties as well as

Sintered powder oxidation variation as a function of build height for titanium alloy produced by electron beam powder-bed fusion

November 26, 2021
Nicholas Derimow, Alejandro Romero, Aldo Rubio, Cesar Terrazas, Francisco Medina, Ryan Wicker, Nik Hrabe
It is well-established that titanium alloy (Ti-6Al-4V) powder oxidizes during electron beam powder-bed fusion (PBF-EB) due to the high background temperatures resulting from layer preheating and sintering of the powder bed before melting. However, it is

Activation of Mechanophores in a Thermoset Matrix by Instrumented Scratch

November 17, 2021
Chelsea S. Davis, Jeremiah Woodcock, Ryan Beams, Mitchell Rencheck, Muzhou Wang, Stephan J. Stranick, Aaron M. Forster, Jeffrey Gilman
Scratches in polymer coatings and barrier layers negatively impact optical properties (haze, light transmission, etc.), initiate routes of degradation or corrosion (moisture permeability), and nucleate delamination of the coating. Detecting scratches in

Evaluation of a Modified Void Descriptor Function to Uniquely Characterize Pore Networks and Predict Fracture Location in Additively Manufactured Metals

November 15, 2021
Dillon Watring, Jake Benzing, Orion Kafka, Li-Anne Liew, Newell Moser, John Erickson, Nik Hrabe, Ashley Spear
Variations in additive manufacturing (AM) processing parameters can lead to variations in porosity, making it challenging to predict pore- or void-sensitive mechanical response in AM metals. A recently developed pore metric, the void descriptor function

Elucidating Proximity Magnetism through Polarized Neutron Reflectometry and Machine Learning

October 29, 2021
Nina Andrejevic, Zhantao Chen, Thanh Nguyen, Leon Fan, Henry Heiberger, Valeria Lauter, Ling-Jie Zhou, Yi-Fan Zhao, Cui-Zu Chang, Alexander Grutter, Mingda Li
Polarized neutron reflectometry (PNR) is a powerful technique to interrogate the structures of multilayered magnetic materials with depth sensitivity and nanometer resolution. However, reflectometry profiles often inhabit a complicated objective function

Antiferromagnetic VdW Phase at the Interface of Sputtered Topological Insulator/Ferromagnet Bi 2 Te 3 /Ni 80 Fe 2 0 Heterostructures

October 28, 2021
Nirjhar Bhattacharjee, Krishnamurthy Mahalingam, Adrian Fedorko, Valeria Lauter, Matthew Matzelle, Bahadur Singh, Alexander Grutter, Alexandria Will-Cole, Michael Page, Michael McConney, Robert Markiewicz, Arun Bansil, Don Heiman, Nian Sun
Magnetic ordering in topological insulators (TI) is crucial for breaking time-reversal symmetry (TRS) and thereby opening a gap in the topological surface states (TSSs) [1-6], which is the key for realizing useful topological properties such as the quantum
Displaying 1 - 25 of 1638