11,208 results match your criteria: "‡National Institute of Standards and Technology[Affiliation]"
Environ Sci Process Impacts
October 2024
Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Previous time-integrated (2 h to 4 h) measurements show that total gas-phase water-soluble organic carbon (WSOC) is 10 to 20 times higher inside homes compared to outside. However, concentration dynamics of WSOC and total particle phase WSOC (WSOC)-are not well understood. During the Chemical Assessment of Surfaces and Air (CASA) experiment, we measured concentration dynamics of WSOC and WSOC inside a residential test facility in the house background and during scripted activities.
View Article and Find Full Text PDFPhys Rev A (Coll Park)
August 2024
Quantum Measurement Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8410, USA.
When an optical beam passes through a thin slice of a homogeneous material, the change of its phase and amplitude is characterized by the material's linear and nonlinear susceptibility, the latter also known as the hyperpolarizability. The standard method for measuring the nonlinear susceptibility is the scan. This widely used method is sometimes applied outside of its range of validity, leading to systematic errors.
View Article and Find Full Text PDFInt J Thermophys
January 2024
National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
A method is described to measure the thermal expansion coefficient of fused quartz glass. The measurement principle is to monitor the change in resonance frequency of a Fabry-Perot cavity as its temperature changes; the Fabry-Perot cavity is made from fused quartz glass. The standard uncertainty in the measurement was less than 0.
View Article and Find Full Text PDFForensic Chem
September 2024
National Institute of Standards and Technology, Gaithersburg, MD, USA.
Forensic Chem
December 2024
National Institute of Standards and Technology, Gaithersburg, MD, USA.
With the lack of standardized validation protocols across the forensic chemistry community, validation of instrumentation can be a challenging and time-consuming task. However, this process is crucial to understanding the associated capabilities and limitations, especially for nascent technologies. Rapid GC-MS is one such emerging analytical technique being increasingly implemented in forensic laboratories due to its fast and informative screening capabilities.
View Article and Find Full Text PDFArch Toxicol
January 2025
PETA Science Consortium International e.V., 70499, Stuttgart, Germany.
Anal Chem
October 2024
Nanoscale Devices Characterization Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States.
Photothermal induced resonance (PTIR), also known as atomic force microscopy-infrared (AFM-IR), enables nanoscale IR absorption spectroscopy by transducing the local photothermal expansion and contraction of a sample with the tip of an atomic force microscope. PTIR spectra enable material identification at the nanoscale and can measure sample composition at depths >1 μm. However, implementation of quantitative, multivariate, nanoscale IR analysis requires an improved understanding of PTIR signal transduction and of the intensity dependence on sample characteristics and measurement parameters.
View Article and Find Full Text PDFNat Commun
October 2024
Singapore Lipidomics Incubator, Life Sciences Institute, National University of Singapore, Singapore, 117456, Singapore.
MAGMA
October 2024
Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA.
Objective: This work presents an automated quality control (QC) system within quantitative MRI (qMRI) workflows. By leveraging the ISMRM/NIST quantitative MRI system phantom, we establish an open-source pipeline for rapid, repeatable, and accurate validation and stability tracking of sequence quantification performance across diverse clinical settings.
Materials And Methods: A microservice-based QC system for automated vial segmentation from quantitative maps was developed and tested across various MRF acquisition and protocol designs, with reports generated and returned to the scanner in real time.
Genome Biol
October 2024
Computer Science and Engineering, University of Michigan, Ann Arbor, Michigan, USA.
In this work, we extend vcfdist to be the first variant call benchmarking tool to jointly evaluate phased single-nucleotide polymorphisms (SNPs), small insertions/deletions (INDELs), and structural variants (SVs) for the whole genome. First, we find that a joint evaluation of small and structural variants uniformly reduces measured errors for SNPs (- 28.9%), INDELs (- 19.
View Article and Find Full Text PDFGenome Res
November 2024
Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, Washington 98195, USA;
Anal Chem
October 2024
Department of Materials and Environmental Chemistry, Stockholm University, Svante Arrhenius väg 16, 11418 Stockholm, Sweden.
Nontargeted screening (NTS) utilizing liquid chromatography electrospray ionization high-resolution mass spectrometry (LC/ESI/HRMS) is increasingly used to identify environmental contaminants. Major differences in the ionization efficiency of compounds in ESI/HRMS result in widely varying responses and complicate quantitative analysis. Despite an increasing number of methods for quantification without authentic standards in NTS, the approaches are evaluated on limited and diverse data sets with varying chemical coverage collected on different instruments, complicating an unbiased comparison.
View Article and Find Full Text PDFJ Phys Chem B
October 2024
State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.
Rev Sci Instrum
October 2024
National Institute of Standards and Technology, Boulder, Colorado 80302, USA.
The frequency stability of a laser locked to an optical reference cavity is fundamentally limited by thermal noise in the cavity length. These fluctuations are linked to material dissipation, which depends on both the temperature of the optical components and the material properties. Here, the design and experimental characterization of a sapphire optical cavity operated at 10 K with crystalline coatings at 1069 nm is presented.
View Article and Find Full Text PDFbioRxiv
October 2024
Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Dr., Gaithersburg, MD 20899, USA.
Pest Manag Sci
January 2025
Citrus Research Institute, Southwest University, National Citrus Engineering Research Center, Chongqing, China.
Background: The citri red mite, Panonychus citri (McGregor), is an important citrus pest worldwide, causing enormous economic losses to citrus production. Bifenazate is a widely used acaricide for controlling P. citri.
View Article and Find Full Text PDFJ Phys Chem B
October 2024
Biological Physics Group, Physics Department, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States.
This study investigates the potential of antimicrobial peptides (AMPs) as alternatives to combat antibiotic resistance, with a focus on two AMPs containing unnatural amino acids (UAAs), E2-53R (16 AAs) and LE-54R (14 AAs). In both peptides, valine is replaced by norvaline (Nva), and tryptophan is replaced by 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (Tic). Microbiological studies reveal their potent activity against both Gram-negative (G(-)) and Gram-positive (G(+)) bacteria without any toxicity to eukaryotic cells at test concentrations up to 32 μM.
View Article and Find Full Text PDFACS Appl Mater Interfaces
October 2024
National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, United States.
Clin Chem
November 2024
National Center for Clinical Laboratories, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, P.R. China.
Background: In previous publications, the Task Force on Reference Measurement System Implementation proposed a procedural approach combining a critical review of entries available in the Joint Committee on Traceability in Laboratory Medicine (JCTLM) database with a comparison of this information against analytical performance specifications for measurement uncertainty (MU) and applied it to a group of 13 measurands.
Content: Here we applied this approach to 17 additional measurands, of which measurements are frequently requested. The aims of the study were (a) to describe the main characteristics for implementing traceability and the potential to fulfill the maximum allowable MU (MAU) at the clinical sample level of certified reference materials and reference measurement procedures listed in the JCTLM database; (b) to discuss limitations and obstacles, if any, to the achievement of the required quality of laboratory measurements; and (c) to provide a gap analysis by highlighting what is still missing in the database.
iScience
September 2024
Department of Materials Science and Engineering, University of North Texas, Denton, TX 76207, USA.
Superconducting transition-edge sensors (TES) have emerged as fascinating devices to detect broadband electromagnetic radiation with low thermal noise. The advent of metallic transition metal dichalcogenides, such as NbSe, has also created an impetus to understand their low-temperature properties, including superconductivity. Interestingly, NbSe-based sensor within the TES framework remains unexplored.
View Article and Find Full Text PDFAdv Mater
November 2024
Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA.
Reducing the dimensions of materials from three to two, or quasi-two, provides a fertile platform for exploring emergent quantum phenomena and developing next-generation electronic devices. However, growing high-quality, ultrathin, quasi2D materials in a templated fashion on an arbitrary substrate is challenging. Here, the study demonstrates a simple and reproducible on-chip approach for synthesizing non-layered, nanometer-thick, quasi-2D semimetals.
View Article and Find Full Text PDFAdv Mater
November 2024
Department of Electrical and Computer Engineering, University of California, Los Angeles, CA, 90095, USA.
Topological insulators (TI) and magnetic topological insulators (MTI) can apply highly efficient spin-orbit torque (SOT) and manipulate the magnetization with their unique topological surface states (TSS) with ultrahigh efficiency. Here, efficient SOT switching of a hard MTI, V-doped (Bi,Sb)Te (VBST), with a large coercive field that can prevent the influence of an external magnetic field, is demonstrated. A giant switched anomalous Hall resistance of 9.
View Article and Find Full Text PDFJ Am Chem Soc
October 2024
Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.
Metal-organic frameworks (MOFs) have shown promise in both capturing CO under flue gas conditions and converting it into valuable chemicals. However, the development of a single MOF capable of capturing and selectively converting CO has remained elusive due to a lack of a harmonious combination of selectivity, water stability, and reactivity. For example, Cu(I)-based MOFs are particularly effective for CO conversion, but they do not typically exhibit selective CO adsorption and often suffer from instability in the presence of air and moisture.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, United States; Department of Physics and Institute for Soft Matter Synthesis and Metrology, Georgetown University, Washington, DC 20057, United States. Electronic address:
Laha et al. studied the diffusive behavior of a whole-blood drop on filter paper using the generalized capillary bundle model. However, some model parameters should be further refined to accurately reflect the physics involved in this diffusion process.
View Article and Find Full Text PDFACS Macro Lett
October 2024
Applied Chemicals and Materials Division, National Institute of Standards and Technology, Boulder, Colorado 80305, United States.