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Search Publications by: Angela R. Hight Walker (Fed)

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Displaying 1 - 25 of 173

Noncryogenic Air Separation using Aluminum Formate Al(HCOO) 3 (ALF)

May 3, 2023
Author(s)
Dinesh Mullangi, Hayden Evans, Taner N. Yildirim, Yuxiang Wang, Zeyu Deng, Zhaoqiang Zhang, Thuc Mai, Fengxia Wei, John Wang, Angela R. Hight Walker, Craig Brown, Dan Zhao, Pieremanuele Canepa, Anthony K. Cheetham
Separating oxygen from air to create oxygen-enriched gas streams is a process that is significant in both industrial and medical fields. However, the prominent technologies for creating oxygen-enriched gas streams are both energy and infrastructure

Thermosensitivity Through Exchange Coupling in Ferrimagnetic/Antiferromagnetic Nano-Objects for Magnetic Based Thermometry

March 6, 2023
Author(s)
Frank Abel, Eduardo De Lima Correa, Adam Biacchi, Thinh Bui, Solomon I. Woods, Angela R. Hight Walker, Cindi L. Dennis
Temperature is a fundamental physical quantity important to the physical and biological sciences. Measurement of temperature within an optically inaccessible three-dimensional (3D) volume at microscale resolution is currently limited. Thermal magnetic

The Impact of Carbon Nanotube Length and Diameter on their Global Alignment by Dead-End Filtration

December 22, 2022
Author(s)
Christopher Rust, Pavel Shapturenka, Manuel Spari, Andreas Bacher, Qihao Jin, Han Li, Markus Guttmann, Ming Zheng, Tehseen Adel, Angela R. Hight Walker, Jeffrey Fagan, Benjamin Flavel
Dead-end filtration on polyvinylpyrrolidone-coated polycarbonate track-etched membranes has proven to be an effective method to prepare macroscopically (3.8 cm²) aligned thin films from solution-based single-wall carbon nanotubes (SWCNTs). However, to make

Control of the Schottky barrier height in monolayer WS2 FETs using molecular doping

August 26, 2022
Author(s)
Siyuan Zhang, Hsun-Jen Chuang, SON LE, Curt A. Richter, Kathleen McCreary, Berend Jonker, Angela R. Hight Walker, Christina Hacker
The development of processes to controllably dope two-dimensional semiconductors is critical to achieving next generation electronic and optoelectronic devices. Understanding the nature of the contacts is a critical step for realizing efficient charge

Polyoxovanadates as Precursors for the Synthesis of Colloidal Multi-Metal Oxide Nanocrystals

March 31, 2022
Author(s)
Adam Biacchi, Lucas Johnson, Ashley Sweet, Eric Cal, Angela R. Hight Walker, Matthew Buck, Luke Barrante
Colloidal multi-metal oxide nanocrystals that contain the element vanadium are attractive materials for enabling diverse technologies. Few nanocrystal systems are synthetically well-developed, however, which is attributable to a scarcity of molecular

Influence of Dimensionality on the Charge Density Wave Phase of 2H-TaSe2

March 23, 2022
Author(s)
Sugata Chowdhury, Albert Rigosi, Heather Hill, David B. Newell, Angela R. Hight Walker, Francesca Tavazza, Andrew Briggs
Metallic transition metal dichalcogenides like tantalum diselenide (TaSe2) exhibit exciting behaviors at low temperatures including the emergence of charge density wave (CDW) states. In this work, density functional theory (DFT) is used to classify the

Synthesis, crystal structure, and physical properties of BaSnS2

February 11, 2022
Author(s)
Wilarachchige Gunatilleke, Andrew May, Angela R. Hight Walker, Adam Biacchi, George Nolas
Phase-pure BaSnS2, with space group Pn21/c, was synthesized and the structural and physical properties were investigated. The thermal properties and optical measurements are reported for the first time. The Debye temperature and Sommerfeld coefficient were

Dependence of Single-Wall Carbon Nanotubes Alignment on the Filter Membrane Interface in Slow Vacuum Filtration

January 22, 2022
Author(s)
Jeffrey Fagan, Angela R. Hight Walker, Adam Biacchi, Andrei Kolmakov, Zia Macdermid, William D. Rice, Joshua Walker, Thomas Searles
The recent development of slow vacuum filtration (SVF) technology has shown great promise for reproducibly producing high-quality, large-area aligned films of single-wall carbon nanotubes (SWCNTs) from solution-based nanotube dispersions. In contrast to

Advanced characterization of magnetization dynamics in iron oxide magnetic nanoparticle tracers

January 5, 2022
Author(s)
Thinh Bui, Adam Biacchi, Brianna Bosch Correa, Cindi L. Dennis, Weston L. Tew, Angela R. Hight Walker, Solomon I. Woods
Characterization of the magnetization dynamics of single-domain magnetic nanoparticles (MNPs) is important for magnetic particle imaging (MPI), magnetic resonance imaging (MRI), and emerging medical diagnostic/therapeutic technologies. Depending on

Synthesis of Mixed-Valent Lanthanide Sulfide Nanoparticles

August 23, 2021
Author(s)
Pricilla Glaser, Orlando Stewart, Rida Atif, Dane Asuigui, Joel Swanson, Adam Biacchi, Angela R. Hight Walker, Gregory Morrison, Hans-Conrad zur Loye, Sarah Stoll
In targeting reduced valence lanthanides, we report the first nanoparticle synthesis of the mixed-valent ferromagnets Eu3S4 and EuSm2S4. Using divalent lanthanide halides with bis(trimethylsilyl)sulfide and oleylamine, we prepared nanoparticles of EuS

The importance of international standards for the graphene community

March 15, 2021
Author(s)
Charles Clifford, Erlon H. Martins Ferreira, Toshiyuki Fujimoto, Jan Herrmann, Angela R. Hight Walker, Denis Koltsov, Christian Punckt, Lingling Ren, Gregory J. Smallwood, Andrew J. Pollard
If graphene and related 2D materials are to be used commercially, buyers need to have confidence in the measured properties of the material they obtain from suppliers. Scientists from international standards committees describe how the first joint ISO/IEC