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NIST Authors in Bold

Displaying 276 - 300 of 2028

Practical Guidelines to 13C-based NMR Metabolomics

August 29, 2019
Author(s)
Arthur S. Edison, Adrien Le Guennec, Frank Delaglio, Eriks Kupce
We present an overview of 13C-based NMR metabolomics. At first glance, the low sensitivity of 13C relative to 1H NMR might seem like too great an obstacle to use this approach. However, there are several advantages to 13C NMR, whether samples can be

Mass Spectrometry Fingerprints of Small-Molecule Metabolites in Biofluids. Building a Spectral Library of Recurrent Spectra for Urine Analysis.

August 19, 2019
Author(s)
Yamil Simon, Ramesh Marupaka, Xinjian Yan, Yuxue Liang, Kelly H. Telu, Yuri A. Mirokhin, Stephen E. Stein
A large fraction of ions observed in electrospray liquid chromatography-mass spectrometry (LC-MS) experiments of biological samples remain unidentified. One the main reasons for this is that spectral libraries of pure compounds fail to account for the

Mass Spectrometry Fingerprints of Small-Molecule Metabolites in Biofluids: Building a Spectral Library of Recurrent Spectra for Urine Analysis

August 18, 2019
Author(s)
Yamil Simon, Ramesh Marupaka, Xinjian Yan, Yuxue Liang, Kelly H. Telu, Yuri Mirokhin, Stephen E. Stein
A large fraction of ions observed in electrospray liquid chromatography–mass spectrometry (LC–ESI-MS) experiments of biological samples remain unidentified. One of the main reasons for this is that spectral libraries of pure compounds fail to account for

Unusual Regularity in GC Retention of Simple Amino Acid Derivatives

August 8, 2019
Author(s)
Anzor I. Mikaia, Nino G. Todua, Zenkevich G. Igor
Background. Application of simple regularities and the general principles along with direct use of reference retention index data is a useful approach for reliable structure determination of compounds by GC-MS. Objective. Interpretation of anomaly in

Ampoules for Radioactivity Standard Reference Materials

August 6, 2019
Author(s)
Ronald Colle
Standard-sized ampoules for radioactive solution standards have been employed by the National Institute of Standards and Technology (NIST) for nearly the past 70 years. This note briefly summarizes the origins and history of the five different batches of

Liquid chromatography tandem mass spectrometry for the quantitation of steroid hormone profiles in blubber from stranded humpback whales (Megaptera novaeangliae)

July 30, 2019
Author(s)
Greta Dalle Luche, Susan Bengston Nash, John Kucklick, Fletcher M. Mingramm, Ashley Russell
Marine mammal blubber is known to have quantifiable concentrations of steroid hormones and is increasingly chosen as a matrix for the detection of these reproductive and stress biomarkers. Steroid hormones act through complex cascades, often in concert

Stability of gaseous volatile organic compounds contained in gas cylinders with different internal wall treatments

July 29, 2019
Author(s)
George C. Rhoderick, Christina Cecelski, Walter R. Miller Jr., David Worton, Sergi Moreno, Paul Brewer, Joele Viallon, Faraz Idrees, Philippe Moussay, Yong D. Kim, Dal H. Kim, Sangil Lee, Annarita Baldan, Jianrong Li
Volatile organic compounds (VOCs) are a group of gas-phase compounds present in the atmosphere that affect air quality and Earth's climate. Halocarbons, a subset of this group, are strong greenhouse gases and are linked to stratospheric ozone depletion

Chemical Identification of Interlayer Contaminants within van der Waals Heterostructures

June 24, 2019
Author(s)
Jeffrey Schwartz, ?Hsun-Jen Chuang, Matthew R. Rosenberger, Saujan V. Sivaram, Kathleen M. McCreary, B.T. Jonker, Andrea Centrone
Van der Waals heterostructures (vdWHs) leverage the characteristics of two-dimensional (2D) material building blocks to create a myriad of structures with unique and desirable properties. Several commonly employed fabrication strategies rely on polymeric

pyMCR: A Python Library for Multivariate Curve Resolution Analysis

June 24, 2019
Author(s)
Charles H. Camp
In this work, a new software library is presented for performing multivariate curve resolution (MCR)analysis, a chemometric method for elucidating signatures of analytes ("endmember extraction") and their relative abundance (regression) from a series of

Revealing the distribution of metal carboxylates in oil paint from the micro- to the nanoscale

June 21, 2019
Author(s)
Xiao Ma, Victoria Beltran, Georg Ramer, Georges Pavlidis, dilworth parkinson, Mathieu Thoury, Tyler Meldrum, Andrea Centrone, Barbara H. Berrie
Oil paints comprise pigments, drying oils, and additives that together confer desirable properties, but can react forming metal carboxylates (soaps) that, over time, may damage artworks. Despite substantial research to understand these phenomena, soap

The Art in Science of MicroTAS 2018

June 21, 2019
Author(s)
Gregory A. Cooksey
The 2018 MicroTAS conference (the 22nd International Conference of Miniaturized Systems for Chemistry and Life Sciences) took us to Kaohsiung, Taiwan, for an inspiring mix of science and culture. The Art in Science competition, sponsored by Lab on a Chip

Diaphragmless Single Pulse Shock Tube for High-Temperature Chemical Kinetics Studies

June 3, 2019
Author(s)
William Sean McGivern, Iftikhar A. Awan, Jeffrey A. Manion
Single pulse shock tubes are effective tools for measuring chemical kinetics at high temperatures, typically (900–1400) K. However, the use of a diaphragm for shock generation leads to significant shock-to- shock inconsistencies in temperature for a

Accelerated Weathering Parameters for Some Aromatic Engineering Thermoplastics

May 24, 2019
Author(s)
Li Piin Sung, James E. Pickett, Olga Kuvshinnikova, Brett Ermi
Samples of polycarbonate (PC), poly(butylene terephthalate) (PBT), a PC/PBT blend, and poly(styrene-co-acrylonitrile) (SAN), all containing 3 % TiO2 (by mass), were exposed in the NIST (National Institutes of Standards and Technology) SPHERE (Simulated

Health Assessment Measurements Quality Assurance Program: Exercise 2 Final Report

May 21, 2019
Author(s)
Charles A. Barber, Jeanice M. Brown Thomas, Carolyn Q. Burdette, Johanna Camara, Stephen E. Long, Melissa M. Phillips, Benjamin J. Place, Catherine A. Rimmer, Laura J. Wood, Lee L. Yu
The NIST Health Assessment Measurements Quality Assurance Program (HAMQAP) was launched in collaboration with the National Institutes of Health (NIH) Office of Dietary Supplements (ODS) in 2017. HAMQAP was established to enable laboratories to improve the

Practical Guides for X-Ray Photoelectron Spectroscopy: First Steps in Planning, Conducting, and Reporting XPS Measurements

May 15, 2019
Author(s)
Cedric J. Powell, Donald R. Baer, Kateryna Artyushkova, Christopher R. Brundle, James E. Castle, Mark Engelhard, Karen Gaskell, John Grant, Richard Haasch, Matthew Linford, Peter Sherwood, Vincent Smentkowski, Alexander Shard
Over the past three decades, the use of x-ray photoelectron spectroscopy (XPS) in research and applications has grown to make XPS the most popular method of surface analysis. There has also been an increase in the number of new or inexperienced users along

Certification of Standard Reference Material 3389 Ginsenoside Calibration Solution

May 10, 2019
Author(s)
Walter B. Wilson, Lane C. Sander, Benjamin J. Place, James H. Yen
Standard Reference Material (SRM) 3389 is intended as a calibration solution for use for the determination of ginsenosides in natural matrix samples. A unit of SRM 3389 consists of two different ampule solutions: (1) four ampules of a six-component mixture

Interlaboratory Comparison of Hydrogen-Deuterium Exchange Mass Spectrometry (HDX-MS) MMeasurements of the Fab fragment of NISTmAb

May 2, 2019
Author(s)
Jeffrey W. Hudgens, Ioannis L. Karageorgos, Elyssia S. Gallagher, Kyle W. Anderson, James J. Filliben, Richard Y. Huang, Guodong Chen, Michael J. Chalmers, Benjamin T. Walters, Jennifer Zhang, John Venable, Caitlin Steckler, In Hee Park, Ansgar Brock, Xiaojun Lu, Ratnesh Pandey, Arun Chandramohan, Ganesh Srinivasan Anand, Sasidhar N. Nirudodhi, Justin Sperry, Jason C. Rouse, James A. Carroll, Kasper D. Rand, Ulrike Leurs, David D. Weis, Mohammed A. Al-Naqshabandi, Tyler S. Hageman, Patrick Wintrode, John D. Lambris, Sarah Urata, George M. Bou-Assaf, Alfonso Espada
Hydrogen-deuterium exchange mass spectrometry (HDX-MS) is an established, powerful tool for investigating protein-ligand interactions, protein folding, and protein dynamics. However, HDX-MS is still an emergent tool for quality control of
Displaying 276 - 300 of 2028