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Displaying 26 - 50 of 72806

CCQM_Retrospectoscope Reference Manual: A detailed reference to the CCQM_Retrospectoscope, a suite of graphical tools for the meta-analysis of measurement results from CCQM studies

September 12, 2023
Author(s)
David L. Duewer, Michael Nelson, Christina Cecelski
The CCQM_Retrospectoscope system combines a nominally complete database of results from Consultative Committee for the Amount of Substance: Metrology in Chemistry and Biology (CCQM) studies with a number of graphical tools for trying to make sense of the

Repeatability of Contactless and Contact Fingerprint Capture

September 12, 2023
Author(s)
John M. Libert, Shahram Orandi, John Grantham, Kenneth Ko, Bruce Bandini
A new generation of contactless fingerprint capture devices has recently emerged. These devices provide the ability to capture a fingerprint without making physical contact with the finger. There is anecdotal evidence that the process of capturing a

Non-flammable Low-GWP Refrigerant Blends to Replace HFC-134a

September 11, 2023
Author(s)
Harrison M. Skye, Piotr A. Domanski, Mark O. McLinden, Valeri I. Babushok, Ian Bell, Tara Fortin, Michael Hegetschweiler, Mark A. Kedzierski, Dennis Kim, Lingnan Lin, Gregory T. Linteris, Stephanie L. Outcalt, Vance (Wm.) Payne, Richard A. Perkins, Aaron Rowane
Non-flammable, lower global-warming-potential (GWP) refrigerants are needed to replace HFC-134a (GWP=1300) in military equipment. We previously used thermodynamic cycle simulations to screen 100 000+ refrigerant blends and identified 23 candidate

Target and Suspect Screening Integrated with Machine Learning to Discover Per- and Polyfluoroalkyl Substance Source Fingerprints

September 11, 2023
Author(s)
Nayantara Joseph, Trever Schwichtenberg, Dunping Cao, Gerrad Jones, Alix Rodowa, Joe Charbonnet, Christopher Higgins, Damian Helbling, Jennifer Field
This study elucidates per- and polyfluoroalkyl substance (PFAS) fingerprints for specific PFAS source types. Ninety-two samples were collected from aqueous film-forming foam impacted groundwater (AFFF-GW), landfill leachate, biosolids leachate, municipal

Gravimetric deposition of microliter drops with radiometric confirmation

September 9, 2023
Author(s)
Denis E. Bergeron, Richard Essex, Svetlana Nour, Gordon A. Shaw, R. Michael Verkouteren, Ryan P. Fitzgerald
A manual gravimetric dispensing technique is demonstrated using a micropipettor modified for use with removeable microcapillaries. Liquid scintillation sources were prepared from a well-characterized 241Am reference solution, providing a radiometric check

Multi'omic Characterization of Human Whole Stool RGTMs

September 8, 2023
Author(s)
Amanda L. Bayless, Sandra M. Da Silva, Clay Davis, Abraham Kuri Cruz, Tracey Schock, Stephanie Servetas, Paulina Piotrowski
The gut microbiome plays a critical role in a vast and disparate set of health and disease states, including cancer and obesity. Human fecal is a complex mixture including microbes, proteins, undigested plant matter and fat content according to the diet

Radiative Decay Rate and Branching Fractions of MgF

September 8, 2023
Author(s)
Eric Norrgard, Catherine Cooksey, Stephen Eckel, Nickolas Pilgram, Kayla Rodriguez, Howard W. Yoon, Yuly Andrea Chamorro Mena, Lukas Pasteka, Anastasia Borschevsky
Here we report measured and calculated values of radiative decay rates and vibrational branching fractions for the A$^2\Pi$ state of MgF. The decay rate measurements use time-correlated single photon counting with roughly 1\,\% total uncertainty. Branching

Simulations of a frequency-chirped magneto-optical trap of MgF

September 8, 2023
Author(s)
Kayla Rodriguez, Nickolas Pilgram, Daniel Barker, Stephen Eckel, Eric Norrgard
We simulate the capture process of MgF molecules into a frequency-chirped molecular MOT. Our calculations show that by chirping the frequency, the MOT capture velocity is increased by about of factor of 4 to 80m/s, allowing for direct loading from a two

Single-photon Sources and Detectors Dictionary

September 7, 2023
Author(s)
Joshua Bienfang, Thomas Gerrits, Paulina Kuo, Alan Migdall, Sergey Polyakov, Oliver T. Slattery
The intention of this dictionary is to define relevant terms and metrics used in the characterization of single-photon detectors and sources with the goal to promote better understanding and communication of those metrics across the single-photon

Quantifying Pairwise Similarity for Complex Polymers

September 6, 2023
Author(s)
Jiale Shi, Nathan Rebello, Dylan Walsh, Michael Deagen, Bruno Salomao Leao, Debra Audus, Bradley Olsen
Defining the similarity between chemical entities is an essential task in polymer informatics, enabling ranking, clustering, and classification. Despite its importance, pairwise chemical similarity for polymers remains an open problem. Here, a similarity

Understanding Stablecoin Technology and Related Security Considerations

September 5, 2023
Author(s)
Peter Mell, Dylan Yaga
Stablecoins are cryptocurrencies whose price is pegged to that of another asset (typically one with low price volatility). The market for stablecoins has grown tremendously – up to almost $200 billion USD in 2022. These coins are being used extensively in

Atom Probe Tomography Using an Extreme Ultraviolet Trigger Pulse

September 1, 2023
Author(s)
Benjamin Caplins, Ann Chiaramonti Debay, Jacob Garcia, Norman A. Sanford, Luis Miaja Avila
Atom probe tomography (APT) is a powerful materials characterization technique capable of measuring the isotopically resolved three-dimensional (3D) structure of nanoscale specimens with atomic resolution. Modern APT instrumentation most often uses an

Federal perspective on critical research issues in nanoEHS

August 31, 2023
Author(s)
Janet Carter, Sri Nadadur, Rhema Bjorkland, William Boyes, Chuck Geraci, Vincent A. Hackley, John Howard, Alan Kennedy, Igor Linkov, Joanna Matheson, Holly Mortensen, Custudio Muinga, Elijah Petersen, Nora Savage, Stacey Standridge, Trey Thomas, Benjamin Trump
This article discusses critical issues and opportunities going forward in nanotechnology environmental, health, and safety (nanoEHS) research from the perspective of Federal Government agency participants in the U.S. National Nanotechnology Initiative (NNI

Safeguarding International Science: Research Security Framework

August 31, 2023
Author(s)
Gregory F. Strouse, Claire M. Saundry, Timothy Wood, Philip Bennett, Mary Bedner
The U.S. science and research ecosystem retains its leadership by actively engaging with the global community through the conduct of mutually beneficial collaborative research and the welcoming of international scientists. Coupled with that, the national

Quantifying the Effect of Guest Binding on Host Environment

August 29, 2023
Author(s)
Angela Stelson, Zack Fishman, Jacob Pawlik, Gosia Musial, Jim Booth, Chris Long, Kathleen Schwarz, Nate Orloff, Hugh Ryan, Angela Grommet, Jonathan Nitschke, Felix Rizzuto
The environment around a host-guest complex is defined by of intermolecular interactions between solvent molecules and counter ions. These interactions govern both the solubility of these complexes and the rates of reactions confined within them11. Such
Displaying 26 - 50 of 72806