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Search Publications

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Displaying 226 - 250 of 2028

IFCC working group recommendations for correction of bias caused by non-commutability of a certified reference material used in the calibration hierarchy of an end-user measurement procedure

June 1, 2020
Author(s)
Johanna Camara, W. Greg Miller, Jeffrey R. Budd, Neil Greenberg, Weykamp Cas, Harald Althaus, Heinz Schimmel, Mauro Panteghini, Vincent Delatour, Ferruccio Ceriotti, Thomas Keller, Douglas Hawkins, Robert Rej, Finlay MacKenzie, Elina van der Hagen, Hubert W. Vesper
Establishing metrological traceability to a matrix-based certified reference material (CRM) that has been validated to be commutable among a group of measurement procedures (MPs) is central to producing equivalent results for a measurand in clinical

Embracing Uncertainty: Modeling Uncertainty in EPMA - Part I

May 21, 2020
Author(s)
Nicholas Ritchie
This is the first in a series of articles which present a new framework for computing the uncertainty in electron excited X-ray microanalysis measurements. This article will discuss the framework and apply it to a handful of simple but useful sub

Infrared and Raman chemical imaging and spectroscopy at the nanoscale

May 19, 2020
Author(s)
Dmitry Kurouski, Alexandre Dazzi, Renato Zenobi, Andrea Centrone
The advent of nanotechnology, and the need to understand the chemical composition at the nanoscale, has stimulated the convergence of IR and Raman spectroscopy with scanning probe methods, resulting in new nanospectroscopy paradigms. Here we review two of

Mass Spectral Library of Acylcarnitines Derived from Human Urine

April 8, 2020
Author(s)
Xinjian Yan, Sanford Markey, Ramesh Marupaka, Qian Dong, Brian T. Cooper, Yuri Mirokhin, William E. Wallace, Stephen Stein
We describe the creation of a mass spectral library of acylcarnitines and conjugated acylcarnitines from the LC–MS/MS analysis of six NIST urine reference materials. To recognize acylcarnitines, we conducted in-depth analyses of fragmentation patterns of

Highland games: A benchmarking exercise in predicting biophysical and drug properties of monoclonal antibodies from amino acid sequences

April 6, 2020
Author(s)
John E. Schiel, Coffman Jon, Bruno Marques, Griesbach Jan, Ambrose Williams, Gisela Ferreira, Rushd Khalaf, David Roush, Charles Haynes
Biopharmaceutical product and process development does not yet take advantage of predictive computational modeling to nearly the degree seen in industries based on smaller molecules. To assess and advance progress in this area, spirited coopetition was

Characterization of triacontyl (C-30) liquid chromatographic columns

March 15, 2020
Author(s)
Lane C. Sander, Catherine A. Rimmer, Walter B. Wilson
Differences in the performance characteristics of seventeen commercial C30 liquid chromatographic columns were studied for the separation of carotenoid isomers. A mixture consisting of nine xanthophyll and hydrocarbon carotenoids were separated under

NIST Reference Materials: Their Purpose and Their Future

March 15, 2020
Author(s)
Steven J. Choquette, David L. Duewer, Katherine E. Sharpless
The National Institute of Standards and Technology (NIST), formerly the National Bureau of Standards, was established by the U.S. Congress in 1901 and charged with establishing a measurement foundation to facilitate U.S. and international commerce. This

Practical Guide for Inelastic Mean Free Paths, Effective Attenuation Lengths, Mean Escape Depths, and Information Depths in X-ray Photoelectron SpectroscopyInformation Depths in X-ray Photoelectron Spectroscopy

February 20, 2020
Author(s)
Cedric J. Powell
Information is provided on four terms that are used for different purposes in X-ray photoelectron spectroscopy (XPS): the inelastic mean free path (IMFP), the effective attenuation length (EAL), the mean escape depth (MED), and the information depth (ID)

New Insights into Female Humpback Whale (Megaptera novaeangliae) Reproductive Endocrinology Revealed by Steroid Hormone Profile Analysis

February 19, 2020
Author(s)
Greta Dalle Luche, Ashley Boggs, John Kucklick, Jasmin Gross, Darryl Hawker, Susan Bengston Nash
The blubber steroid hormone profiles of 52 female humpback whales migrating along the east coast of Australia were investigated for possible seasonal endocrinological changes associated with reproduction. Individuals were randomly sampled in southeast

Optimization of Confined DART-MS

February 14, 2020
Author(s)
Edward R. Sisco, Matthew E. Staymates, Thomas P. Forbes
The use of direct analysis in real time mass spectrometry (DART-MS) is seeing increased use in a number of fields, including forensic science, environmental monitoring, food safety, and healthcare. With the increased use, novel configurations have been

Low-temperature time-resolved phosphorescence excitation emission matrices for the analysis of phenanthro-thiophenes in chromatographic fractions of complex environmental extracts

February 6, 2020
Author(s)
Sadia Arif, Maha Al-Tameemi, Walter Brent Wilson, Stephen Wise, Fernando Barbosa Jr., Andres Campiglia
Polycyclic aromatic sulfur heterocycles (PASHs) are sulfur analogues of polycyclic aromatic hydrocarbons (PAHs) widely found in environmental samples exposed to oil contamination. Despite their potential carcinogenic and mutagenic properties, only few

Applying Planar, Patterned, Multimetallic Samples to Assess the Impact of Analysis Area in Surface-Chemical Analysis: results of a VAMAS Interlaboratory Comparison

February 3, 2020
Author(s)
Christina Passiu, WES Unger, P Rupper, L Gregoratti, M Amanti, P Zeller, C Malitesta, S Rella, SJ Spencer, A Shard, A Kim, Shinichiro N. Muramoto, M Engelhard, B Hagenhoff, B Bock, R Heuberger, P Dietrich, A Thissen, M Kjaervik, D Paul, J Newman, T Weimann, S Butefisch, ND Spencer, A Rossi
The lateral resolution of a surface-analysis instrument is commonly measured as one of the indicators of the quality of obtainable analytical results. Different methods exist to measure this quantity, and traditionally the employed method/reference sample
Displaying 226 - 250 of 2028