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Alexandria Will-Cole, A. Gilad Kusne, Peter Tonner, Cunzheng Dong, Xianfeng Liang, Nian Sun
Bayesian optimization (BO) is a well-developed machine learning (ML) field for black-box function optimization. In BO, a surrogate predictive model, here a Gaussian process, is used to approximate the black-box function. The estimated mean and uncertainty
Thuy Tran Le, Kumari Shilpa, Choongsze Lee, Sungmin Han, Conan Weiland, Simon Bare, Paul Dauenhauer, Jeffrey Rimer
Developing structure-performance relationships with the underlying goal of optimizing known zeolite catalysts involves the manipulation of their physicochemical properties. Here, we systematically assessed the impact of mesoscopic gradients in acid site
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
Tae-Hwan Jang, Seung-Hwan Do, Minseong Lee, Hui Wu, Craig Brown, Andrew D. Christianson, Sang-Wook Cheong, Jae-Hoon Park
We report magnetization (χ, M), magnetic specific heat (CM), and neutron powder diffraction results on a quasi-two-dimensional (2D) S = 2 square lattice antiferromagnet Ba 2FeSi 2O 7 consisting of FeO 4 tetrahedrons with highly compressive tetragonal
Materials researchers are generating data in ever-increasing volumes, and this data is, in turn, fueling the discovery and design of new materials. These changes are enabled by advances in data capture via laboratory information management systems (LIMS)
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
Evan Jahrman, Jamie Weaver, Niranjan Govind, Marko Perestjuk, Gerald Seidler
There is considerable need for robust, accessible, and non-destructive Fe redox analysis methods for silicate-based minerals and glasses. A popular method assigns the distribution of Fe2+ and Fe3+ atoms using pre-edge features in the Fe K-edge X-ray
Tawanda J. Zimudzi, Sarah E. Sheffield, Kathleen E. Feldman, Peter Beaucage, Dean DeLongchamp, Douglas I. Kushner, Christopher Stafford, Michael A. Hickner
The orientation of polyamide thin films on non-porous substrates was investigated using Fourier transform infrared (FTIR) spectroscopy and corroborated by near edge X-ray absorption fine structure (NEXAFS) measurements. Polyamide films comprised of m
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
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
New software, in the form of Microsoft Excel 2016 spreadsheets, has been created for the analysis and qualification of Charpy Verification Lots, to be used by personnel of the Charpy Verification Program at NIST in Boulder, Colorado. The new spreadsheets
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
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
Francesca Tavazza, Chandler A. Becker, Ursula R. Kattner, Joshua Gabriel, Noah Palson, Thien Duong, Marius Stan
Atomic-scale modeling methods such as density functional theory (DFT) and molecular dynamics (MD) can predict the thermodynamic properties of materials at a lower cost than experimental measurements. However, their regular usage in thermodynamic model
Sri Vikram Palagummi, Taeseung Hong, Li Jiang, Martin Chiang
Objectives: To resolve applicability of the pulse-delay photocuring technique to restorative dental composites as a clinical strategy for the reduction in the detrimental polymerization stress. Methods: Model dental composites with high and low-filler
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
D. Potashnikov, E. Caspi, A. Pesach, Q. Tao, J. Rosen, D. Sheptyakov, Hayden Evans, C. Ritter, Z. Salman, P. Bonfa, T. Ouisse, M. Barbier, O. Rivin, A. Keren
We report μSR on the 2D rare earth based parent magnets (Mo 2/3RE 1/3) 2AlC with RE = Nd, Gd, Tb, Dy, Ho and Er, and neutron diffraction on the series with RE ≠ Gd (a neutron absorber). By crossing information between the two techniques, we determine the
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
Samuel Berweger, Robert Tyrrell-Ead, Houchen Chang, Mingzhong Wu, Hong Tang, Hans Nembach, Karl Stupic, Stephen E. Russek, Thomas Mitchell (Mitch) Wallis, Pavel Kabos
We present images of spin-wave excitations in a patterned yttrium iron garnet (YIG) thin film obtained by use of near-field microwave microscopy, which can achieve spatial resolution as high as 50 nm. Visualization of magnetic excitations is an enticing