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Search Publications

NIST Authors in Bold

Displaying 2951 - 2975 of 74634

The irony of the magnet system for Kibble balances -- a review

March 1, 2022
Author(s)
Stephan Schlamminger, Shisong Lo
The magnet system is an essential component in the Kibble balance, supplying the magnetic flux that plays a vital role as the geometric factor $Bl$. Ironically, the $Bl$ factor cancels out and does not appear in the final Kibble equation. Nevertheless

The Structure of Lipids and Keratin in Adhesive Gecko Setae Determined by NEXAFS Imaging

March 1, 2022
Author(s)
Daniel A. Fischer, Cherno Jaye, Katinka R. Holler, Mette H. Rasmussen, Joe E. Baio, Stanislav N. Gorb, Tobias Weidner
Geckos have the astonishing ability to climb on vertical surfaces due to the adhesive properties of fibrous setae at the tips of their toe pads. While the adhesion mechanism principle, based on van-der-Waals interactions of myriads of spatula located at

Wildfire Smoke Impacts on Residential Indoor Air Quality

March 1, 2022
Author(s)
Steven Emmerich, Chrissi Antonopoulos, Patricia Graef, Rick Karg, Brett Singer, Eric Werling
Wildland fires are occurring with increased frequency and intensity throughout many areas of the world and wildfire smoke exposure is becoming a seasonal event in many communities. Increases in property loss, Illness, and mortality are well documented

WUI Structure/Parcel/Community Fire Hazard Mitigation Methodology

March 1, 2022
Author(s)
Alexander Maranghides, Eric Link, Shonali Nazare, Steven Hawks, Jim McDougald, Stephen Quarles, Daniel Gorham
In the last twenty years, wildland-urban interface (WUI) fires have been growing in severity and size. The structures destroyed by WUI fires have devastated entire communities and have cost billions of dollars while significantly impacting the social

Accurate Determination of Hubble Attenuation and Amplification in Expanding and Contracting Cold-Atom Universes

February 28, 2022
Author(s)
Swarnav Banik, Monica Gutierrez Galan, Hector Sosa Martinez, 1, Madison Anderson, Stephen Eckel, Ian Spielman, Gretchen K. Campbell
In the expanding universe, relativistic scalar fields are thought to be attenuated by "Hubble friction," which results from the dilation of the underlying spacetime metric. By contrast, in a contracting universe this pseudofriction would lead to

Erratum: Collisions of room temperature helium with ultra-cold lithium and the van-der-Waals bound state of HeLi [Phys. Rev. A 101, 012702 (2020)]

February 28, 2022
Author(s)
Constantinos Makrides, Daniel Barker, James A. Fedchak, Julia Scherschligt, Stephen Eckel, Eite Tiesinga
We have found an error in the computation of the thermally-averaged total elastic rate coefficient for the collision of a room-temperature helium atom with an ultra-cold lithium atom presented. We omitted the factor $2/\sqrt\pi}$ in the normalization over

Grassmannian Shape Representations for Aerodynamic Applications

February 28, 2022
Author(s)
Olga Doronina, Zachary J. Grey, Andrew Glaws
Airfoil shape design is a classical problem in engineering and manufacturing. Our motivation is to combine principled physics-based considerations for the shape design problem with modern computational techniques informed by a data-driven approach

Imaging 3D molecular orientation by orthogonal-pair polarization IR microscopy

February 28, 2022
Author(s)
Shuyu Xu, Chad R. Snyder, Jeremy Rowlette, Young Jong Lee
Anisotropic molecular alignment occurs ubiquitously and often heterogeneously in three dimensions (3D). However, conventional imaging approaches based on polarization can map only molecular orientation projected onto the 2D polarization plane. Here, an

Separations by Shape: Molecular Shape Recognition in Liquid Chromatography

February 28, 2022
Author(s)
Lane C. Sander
Molecular shape can provide a basis for chromatographic separations that is distinct from other interaction mechanisms often considered in liquid chromatography. Molecular shape recognition, or shape selectivity, is most evident for the separation of

Towards improved FAIRness of the ThermoML Archive

February 28, 2022
Author(s)
Demian Riccardi, Zachary Trautt, Ala Bazyleva, Eugene Paulechka, Vladimir Diky, Joe W. Magee, Andrei F. Kazakov, Scott Townsend, Chris Muzny
The ThermoML archive is a subset of Thermodynamics Research Center (TRC) data holdings corresponding to cooperation between NIST TRC and five journals: Journal of Chemical Engineering and Data (ISSN: 0021-9568), The Journal of Chemical Thermodynamics (ISSN

The Very Small-Angle Neutron Scattering Instrument at the National Institute of Standards and Technology

February 27, 2022
Author(s)
John Barker, James Moyer, Steven Kline, G. Jensen, Jeremy Cook, Cedric V. Gagnon, Elizabeth Kelley, Jean Philippe Chabot, Nicholas C. Maliszewskyj, Chirag B. Parikh, Wangchun Chen, C. Glinka
A description and the performance of the Very Small-Angle Neutron Scattering (VSANS) Diffractometer at the National Institute of Standards and Technology are presented. The measurement range of the instrument extends over three decades of momentum transfer

Impacts of ingested MWCNT-Embedded nanocomposites in Japanese medaka (Oryzias latipes)

February 26, 2022
Author(s)
Melissa Chernick, Alan Kennedy, Treye Thomas, Keana C. K. Scott, Christine Ogilvie Hendren, Mark Wiesner, David Hinton
Polymer nanocomposites combine the versatile, lightweight characteristics of polymers with the properties of nanomaterials. Polyethylene terephthalate glycol (PETG) is commonly used in polymer additive manufacturing due to its controllable transparency

Novel or Improved NDE Inspection Capabilities for Additively Manufactured Parts

February 26, 2022
Author(s)
Ward L. Johnson, Anne-Francoise Obaton, Alex Van den Bossch, Bryan Butsch, Imane Zouggarh, Olivier Burnet, Florent Soulard
Additive manufacturing (AM) enables the production of parts with extremely complex shapes, such as lattice structures and internal structures (cavities, channels). As a result of this geometric complexity, the applicability of most conventional

Predicting solar cell performance from terahertz and microwave spectroscopy

February 26, 2022
Author(s)
Hannes Hempel, Edwin J. Heilweil, Timothy Magnanelli
Mobilities and lifetimes of photogenerated charge carriers are core properties of photovoltaic materials and can both be characterized by contactless terahertz or microwave measurements. Previously reported values for lead-halide perovskites vary by orders
Displaying 2951 - 2975 of 74634