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Xinyu Li, Maribel Garc?a-Ib??ez, Brendan Carter, Baoshen Chen, Qian Li, Regina Easley, Wei-Jun Cai
Ocean acidification, a phenomenon of seawater pH decreasing due to increasing atmospheric CO2, has a global effect on seawater chemistry, marine biology, and ecosystems. Ocean acidification is a gradual and global long-term process that demands high
The chemical analysis of homemade explosives (HMEs) and improvised explosive devices (IEDs) remains challenging for fieldable analytical instrumentation and sensors. Complex explosive fuel-oxidizer mixtures, black and smokeless powders, flash powders, and
Interaction polymer chromatography (IPC) is an umbrella term covering a large variety of primarily enthalpically-dominated macromolecular separation methods. These include temperature- gradient interaction chromatography, interactive gradient polymer
Nicholas Ritchie, Dale E. Newbury, John Fournelle, Aurelien Moy, Heather Lowers, Anette von der Handt, Paul Carpenter, Emma Bullock, John Donovan
The electron excited microanalysis community is increasingly running into the limitations of its ability to derive accurate an composition from measured x-ray intensities. Many of these limitations could be mitigated if the standard matrix correction
Partition coefficients describe the relative concentration of a chemical equilibrated between two phases. In the design of air samplers, the sorbent-air partition coefficient is a critical parameter, as is the ability to extrapolate or predict partitioning
NIST Special Publication (SP) 922 is an aid in the identification of the chemical structures of polycyclic aromatic hydrocarbons (PAHs). The Structure Index consists of two parts: (1) a cross index of named PAHs listed in alphabetical order and (2)
Meryl B. Cruz, Benjamin Place, Laura J. Wood, Aaron A. Urbas, Werickson Rocha, Andrzej Wasik
The lack of stringent regulations regarding raw materials for herbal supplements used for medicinal purposes has been a constant challenge in the industry. Ginkgo biloba L. leaf extracts attract consumers because of the supposed positive effect on mental
The 2019 MicroTAS conference (the 23rd International Conference of Miniaturized Systems for Chemistry and Life Sciences) held in Basel, Switzerland, brought great opportunities to viewinspiring microscale compositions. Many of the best images were
The effective attenuation length (EAL) is a useful parameter in quantitative applications of X- ray photoelectron spectroscopy (XPS). This parameter is used in place of the inelastic mean free path (IMFP) in expressions for different XPS applications to
Concepcion A. Remoroza, Tytus D. Mak, Yuri A. Mirokhin, Sergey L. Sheetlin, Xiaoyu Yang, Stephen E. Stein, Power L. Michael, San Andres V. Joice, Yuxue Liang
This study significantly expands both the scope and method of identification for construction of a previously reported tandem mass spectral library of 74 human milk oligosaccharides (HMOs) derived from results of LC-MS/MS experiments. In the present work
Hugh V. Hayes, Walter B. Wilson, Anthony M. Santana, Andres D. Campiglia, Lane C. Sander, Stephen A. Wise
High-performance liquid chromatography with fluorescence detection is often used for the analysis of polycyclic aromatic hydrocarbons (PAH) in environmental extracts. Since fluorescence chromatograms are usually recorded at a single set of excitation and
Shannon T. Krauss, Thomas Forbes, Jeffrey A. Lawrence, John G. Gillen, Jennifer R. Verkouteren
Portable analytical instrumentation that can provide an alarm indication for the presence of explosives and related components is critical for the identification of explosives‐based hazards and threats. Many explosives incident reports involve an inorganic
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
This study describes the use of inkjet printing for the preparation of test materials containing gold nanoparticles (AuNPs) on a biologically relevant matrix, and discusses the methods of using time-of-flight secondary ion mass spectrometry (ToF-SIMS) for
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
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
Erik R. Andersson, Tracey Johnston, Joseph A. Stewart, Russell D. Day, Thierry M. Work, Cheryl M. Woodley
Growth anomalies (GAs) impact both coral skeleton and soft tissues and are detrimental to reef health. This tumor-like disease is increasingly found throughout the tropics and is commonly associated with high human population density, yet little is known
David Sheen, Vincent K. Shen, Robert G. Brinson, Luke Arbogast, John Marino, Frank Delaglio
Protein therapeutics are vitally important clinically and commercially, with monoclonal antibody (mAb) therapeutic sales alone accounting for $115 billion in revenue for 2018.[1] In order for these therapeutics to be safe and efficacious, their protein
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
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
John R. Sieber, John L. Molloy, Nathanael A. Heckert
The National Institute of Standards and Technology has issued its first Standard Reference Materials for elemental analysis of polyvinyl chloride. The custom designed PVC blends contain elements regulated in consumer products by the United States, the
The National Institute of Standards and Technology is currently developing reference materials (RMs) to support the corn-to-ethanol industry. Two candidate RMs consisting of dried corn biomass intermediates before and after conversion (fermentation) were