National Institute of Standards and Technology

Recommended Second Virial Coefficients for Nitrogen and Oxygen

We provide recommended values for the second virial coefficient, B(T), and its uncertainty, for molecular nitrogen and oxygen. The temperature range covered is 20–3000 K for nitrogen and 20–2000 K for oxygen. The recommendations are based on tuning previously published state-of-t...

High‐Efficiency InGaP‐on‐Insulator Microresonator Nonlinear Conversion and Entanglement Generation

ABSTRACT InGaP‐on‐insulator (InGaP‐OI), with its intrinsically high optical nonlinearity, has emerged as an efficient and bright integrated photonic platform for frequency conversion and on‐chip entanglement generation, but high waveguide propagation loss in the visible wavelengt...

Speed of Sound Measurements of n -Dodecane, 2,2,4,4,6,8,8-Heptamethylnonane, and Toluene

Abstract Speed of sound data measured using a dual-path pulse-echo instrument are reported for n-dodecane, 2,2,4,4,6,8,8-heptamethylnonane (isocetane), and toluene. These data are reported at temperatures ranging from 230 to 420 K and at pressures up to 49.7 MPa. The combined exp...

Musculoskeletal MRI Relaxometry Phantom for T1 , T2 , and T1ρ Measurements

ABSTRACT Background Quantitative MRI (qMRI) requires quality assurance methods that reflect in vivo conditions to ensure consistent measurements with low bias and high reproducibility over time, across multiple sites, and across different MRI scanner manufacturers and models. Pur...

Fast, optimal readout of a tethered optomechanical pressure sensor

We demonstrate a fast readout method for tethered optomechanical pressure sensors. The fast readout method allows mechanical ringdown measurement rates that exceed the total mechanical damping rate Γt. We model the uncertainty of our ringdown measurements with the Cramér-Rao boun...

Statistical and deep learning approaches for predicting degradation of polymeric materials in photovoltaics

Polymeric materials are widely used in photovoltaic (PV) systems, making it essential to understand their service life to ensure reliable PV performance. The primary failure mechanism of polymeric materials in PV systems is photodegradation caused by ultraviolet (UV) radiation. D...

X-ray absorption and resonant x-ray emission at the carbon edge of Li2CO3

While highly successful, density functional theory is known to have limitations owing to its neglect of many-body electron-electron interactions. This neglect leads to errors in the single-particle energies, leading to underestimated bandgaps and bandwidths as well as errors in b...

Elastic modulus of recycled aggregate concrete: a multiscale-multiphase modeling approach

Abstract Concrete is a multiscale, multiphase composite material whose elastic properties are challenging to predict, particularly when recycled aggregates are used. The inclusion of recycled aggregates introduces greater heterogeneity due to residual mortar, microcracks, and var...

Explainable Binary Classification of Separable Shape Ensembles

Abstract Scientists, engineers, biologists, and technology specialists universally leverage image segmentation to extract shape ensembles containing many thousands of curves representing patterns in observations and measurements. These large curve ensembles facilitate statistical...

Redefining reference materials for the evolving metabolomics landscape

Abstract The evolution of metabolomics, a field aimed at comprehensively measuring the small organic molecule composition of a biological matrix, fundamentally reshaped the landscape of analytical measurement reliability. The 2011 release of Standard Reference Material (SRM) 1950...

Prior infection of harlequin toads by Batrachochytrium dendrobatidis alters their immune-microbial state and increases mortality upon re-infection

Abstract Strategies to improve survival of wildlife impacted by emerging infectious disease are needed for species of conservation concern. We investigated how prior infection by the skin fungal pathogen, Batrachochytrium dendrobatidis (Bd), affected subsequent disease outcomes i...

Isothermal Captureand Release of Carbon Dioxide witha Porous Molecular Hexaamine

Abstract The decarbonization of fossil fuel combustion streams and air is imperative to achieve negative carbon emissions and requires discovery of new materials that exhibit high CO2 capacities, long-term stability, and minimal energy input for the release of pure CO2. Numerous...

Influence of many-body correlation and mixed-valence fluctuations on X-ray magnetic circular dichroism and resonant inelastic X-ray scattering spectra

X-ray magnetic circular dichroism (XMCD) and resonant inelastic X-ray scattering with magnetic circular dichroism (RIXS-MCD) provide unparalleled insights into the electronic and magnetic dynamics of complex materials. However, interpreting their spectra in mixed-valence systems...

Electromagnetically induced transparency and population repump readout of Rydberg states of Cs atoms in a J-scheme

Rydberg atom electrometry offers traceable electric field measurements over many decades of radio frequencies in a single device. Miniaturization of these sensors is primarily limited by the requirements of the lasers used. Here, we demonstrate a three-photon sensing scheme using...

Breaking voltage-controlled magnetic anisotropy–magnetoresistance trade-off for ultralow-energy switching in magnetic tunnel junctions

Electric-field control of spin states offers a promising route to ultralow-power, ultrafast magnetization switching in spintronic devices such as magnetic tunnel junctions (MTJs). However, enhancing voltage-controlled magnetic anisotropy (VCMA) through interfacial engineering oft...

Room-temperature multiferroicity in all–van der Waals heterostructures

Multiferroics host simultaneous and coupled ferroic orders, allowing disparate external stimuli to induce abrupt transformations in their structures and properties. Creating multiferroicity in two-dimensional (2D) van der Waals (vdW) platforms would add the elements of strong qua...

Understandingthe Electronic Structure of RutheniumOxides during Redox Cycling with High Energy Resolution X-rayAbsorption Spectroscopy

Abstract Ruthenium oxides are essential catalysts and charge storage materials whose performance across reactions, from the oxygen evolution reaction to the chlor-alkali process, depends critically on reversible Ru redox cycling and the associated electronic structure changes. Al...

Identificationof the Site of the Fe–S Clusterin CPSF30 via Metal-Coupled Oxidation-Mass Spectrometry

Abstract Cleavage and polyadenylation specificity factor 30 (CPSF30) is a zinc finger protein that plays a key role in pre-mRNA processing by recognizing specific AU-rich sequence elements to facilitate polyadenylation. CPSF30 contains five highly conserved domains made up of thr...

Toxicity and DNA Adduct Formation Reinforce AI-Guided Prediction of Aflatoxin B1 Bioactivation in VERO E6 Cells

VERO cells, derived from the kidney epithelium of the African green monkey, are widely used in virology, but their ability to metabolize xenobiotics is not fully understood. Since cytochrome P450 (CYP) enzymes participate in xenobiotic metabolism, we investigated which CYP genes...