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Jingyu Liu, Fan Zhang, Andrew J. Allen, Aaron Johnston-Peck, John M. Pettibone
The processing of nanomaterials in natural and engineered systems, which controls their fate and performance, is determined by the relative rates of the predominant reaction pathways present. Commonly used techniques for determining the reaction kinetics
The accurate measurement of uranium isotope ratios from trace samples lies at the foundation of achieving nuclear non-proliferation. These challenging measurements necessitate both the continued characterization and evaluation of evolving mass
Nicole L. Ritzert, Veronika Szalai, Thomas P. Moffat
Understanding the role of macroscopic and atomic defects in the interfacial electron transfer properties of layered transition metal dichalcogenides is important in optimizing their performance in energy conversion and electronic devices. Means of
Maha Al-Tameemi, Sadia Arif, Andres Campiglia, Walter Brent Wilson, Stephen Wise
The dispersion of harmful oil components into the ocean waters could pose long-term risks to flora and fauna. Due to the complexity of oil-contaminated sites, the unambiguous identification and quantitation of environmental pollutants often requires the
Dianne L. Poster, Carl C. Miller, Yaw S. Obeng, Michael T. Postek, Troy E. Cowan, Richard A. Martinello
Nation-wide, healthcare-associated infections (HAIs) infect one in every 25 hospital patients, account for more than 100,000 deaths and increase medical costs by around $96-147B, each year. Ultraviolet-C (UV-C) antimicrobial devices are shown to reduce the
The baseline separation of benzo[a]pyrene in complex samples via reversed-phase liquid chromatography (RPLC) is particularly challenging due to the potential for interferences from other molecular mass 252 (MM, g/mol) polycyclic aromatic hydrocarbons (PAHs
The purpose of the NIST Database for the Simulation of Electron Spectra for Surface Analysis (SESSA) is to facilitate quantitative interpretation of Auger-electron and X-ray photoelectron spectra (AES/XPS) for surface analysis and to improve the accuracy
The research presented here describes the development of two analytical methods for use in the certification of a ginsenoside calibration solution Standard Reference Material (SRM) 3389 consisting of seven ginsenosides: Rg1, Re, Rf, Rb1, Rc, Rb2, and Rd
A non-tomographic approach based on polarization-dependent infrared (IR) spectroscopy is proposed for a simultaneous measurement of the 3D angles and the orientational order parameter of a molecular orientation distribution. Unlike conventional
Refractive index retrievals (also termed inverse Mie methods or optical closure) have seen considerable use as a method to extract the refractive index of aerosol particles from measured optical properties. Retrievals of an aerosol refractive index use two
Silicon wafer-based internal reflection elements (IREs) present many practical advantages over the prisms conventionally used for attenuated total reflection spectroscopy in the infrared. We examine two methods of using minimally prepared IREs that have
Protactinium-233 (233Pa) is used as a tracer for radiochemical analysis and is of particular interest as an isotope dilution mass spectrometry (IDMS) spike for 231Pa/235U radio- chronometry. To this end, we present massic activity determinations by two
Kavita M. Jeerage, Tammy L. Oreskovic, Nikki S. Rentz, Damian S. Lauria
Based on its standard reduction potential, ferriciniummethanol can act as an alternate electron acceptor to oxygen during cellular metabolism. By locally oxidizing ferrocenemethanol at a platinum microelectrode, we probed the activity of individual human
Evagelia C. Laiakis, Tytus Mak, Steven J. Strawn, Yi-Wen Wang, Bo-Hyun Moon, Pelagie Ake, Albert J. Fornace
Exposures to ionizing radiation (IR) may either be accidental or intentional, for medical purposes or even through terrorist actions. As certain populations emerge to be more radiosensitive than others, it is imperative to assess those individuals and
Mohit Tuteja, Minjee Kang, Cecilia Leal, Andrea Centrone
Paclitaxel is a powerful drug against restenosis and many forms of cancer. However, its clinical application hinges on the ability to achieve suitable stabilized drug concentrations in an aqueous suspension while hindering drug crystallization. To engineer
The National Institute of Standards and Technology has developed a new series of organic As reference materials, SRMs 3030, 3031, 3033 and 3034, for monomethylarsonic acid, dimethylarsinic acid, arsenobetaine and arsenocholine, respectively. These SRMs
J. M. Betz, Catherine Rimmer, Leila Saldanha, Melissa Phillips, Karen Andrews, Stephen A. Wise, Laura J. Wood, Adam J. Kuszak, Pavel A. Gusev, Pamela R. Pehrsson
Michael A. Nelson, Jason F. Waters, Blaza Toman, Brian E. Lang, Alexander R?ck, Kathrin Breitruck, Markus Obkircher, Anthony Windust, Katrice A. Lippa
Metrological traceability to common references supports the comparability of chemical measurement results produced by different analysts, at various times, and at separate places. Ideally, these references are realizations of base units of the
Werickson Fortunato de Carvalho Rocha, David Sheen, Dan Bearden
Recent progress in metabolomics has been aided by the development of analysis techniques such as gas and liquid chromatography coupled with mass spectrometry (GC-MS and LC-MS) and nuclear magnetic resonance (NMR) spectroscopy. The vast quantities of data
Georg Ramer, Francesco Ruggeri, Aviad Levin, Toumas Knowles, Andrea Centrone
The conformational structure and folding of proteins are central to many biological processes. However, misfolding of proteins and peptides can lead to toxic aggregates that are involved in Alzheimers and other neurodegenerative disorders. Methods to
Concepcion A. Remoroza, Tytus D. Mak, M. L. De Leoz, Yuri A. Mirokhin, Stephen E. Stein
We report the development and availability of a mass spectral reference library for oligosaccharides in human milk. This represents a new variety of spectral library that includes consensus spectra of compounds annotated through various data analysis
Hugh Hayes, Walter Wilson, Lane Sander, Stephen Wise, Andres Campiglia
The identification of isomeric polycyclic aromatic hydrocarbons (PAHs) in complex samples via reversed-phase liquid chromatography (RPLC) with fluorescence detection (FL) is normally based on matching the chromatographic retention times of suspected peaks
When analyzing an unknown by electron-excited energy dispersive X-ray spectrometry with the entire periodic table possibly in play, how does the analyst discover minor and trace constituents when their peaks are overwhelmed by the intensity of an
Glucose and Creatinine are frequently measured substances in human blood/serum to assist in assessing the health status of individuals. Because of their clinical significance, CCQM-K11 Determination of Glucose in Serum and CCQM-K12 Determination of