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Patrick Egan, Jack A. Stone Jr., Jacob Edmond Ricker, Jay H. Hendricks
We have developed a new low pressure sensor which is based on the measurement of (nitrogen) gas refractivity inside a Fabry-Perot (FP) cavity. We compare pressure determinations via this laser refractometer to that of well-established ultrasonic manometers
Zheng Zhang, Xiaoyu Yang, Yuri A. Mirokhin, Dmitrii V. Tchekhovskoi, Weihua Ji, Sanford P. Markey, Pedatsur Neta, Bowen A. Michael, Stephen E. Stein
Derivatizing peptides with isobaric tags such as iTRAQ and TMT is widely employed in proteomics due to their ability to multiplex quantitative measurements. We recently made publicly available a large peptide library derived from iTRAQ 4-plex labeled
Elisabeth Mansfield, Ian H. Bell, Stephanie L. Outcalt
To develop comprehensive models for multi-component natural gas mixtures (and other applications), it is necessary to have binary interaction parameters for each of the pairs of constituent uids that form the mixture. Good interaction parameters rely on a
Jessica L. Reiner, John Bowden, Ian Christie, Matthew P. Guillette, Theresa M. Cantu, Russell H. Lowers, Hannes Botha, Wilmien Luus-Powell, Willem J. Smit, Danny Govender, Danie Pienaar, Louis J. Guillette Jr.
Perfluorinated alkyl acids (PFAAs) are environmental contaminants that have been used in many products for over 50 years. Interest and concern has grown since 2000 on the widespread presence of PFAAs, when it was discovered that PFAAs were present in
Rian You, James Radney, Michael R. Zachariah, Christopher D. Zangmeister
Optical absorption spectra of laboratory generated aerosols consisting of black carbon (BC) internally mixed with nonabsorbing materials (ammonium sulfate, AS, and sodium chloride, NaCl) and BC with a weakly absorbing brown carbon surrogate derived from
We discuss the implementation of a REDOR experiment that is capable of measuring multiple, weak 13C-2H dipolar couplings when 2H is a strong quadrupole and 13C exhibits large chemical shift anisotropy. We find that at 7.05 T in the presence of large 13C
The rapid and sensitive detection of sugar alcohols sweeteners was demonstrated using ion mobility spectrometry (IMS). IMS provides a valuable compromise in sensitivity, cost, and analysis speed between centralized liquid chromatography-mass spectrometry
Shahana S. Khurshid, Steven Emmerich, Andrew K. Persily
The hydroxyl radical (OH) generating capacity of particles has been measured in several outdoor locations, but it remains unquantified in indoor environments where extended periods of exposure are likely. Total suspended particle samples were collected
Low temperature conductivity mechanisms are identified in acceptor doped BaTiO3 single crystals equilibrated and quenched from high temperature under different oxygen partial pressures. A range of acceptor ionization states are quenched into samples doped
Mark S. Lowenthal, Kiersta S. Davis, Lisa E. Kilpatrick, Catherine A. Mouchahoir, Karen W. Phinney
N-glycosylation is well known to occur at asparagine residues in the canonical consensus sequence N-X-S/T, but has also been identified at a small number of N-X-C motifs including the Asn491 residue of human serotransferrin. Here we report additional novel
We propose a standard data format for the interchange of XAFS data. The XAFS Data Interchange (XDI) standard is meant to encapsulate a single spectrum of XAFS along with relevant metadata. XDI is a text-based format with a simple syntax which clearly
Kevin O. Douglass, Zeeshan Ahmed, Douglas A. Olson
We present recent work aimed at creating a standard for the dynamic measurement of pressure. A near-IR laser spectroscopy system is demonstrated for measuring 8 cm-1 in 50 µs with a 4 kHz repetition rate.
Aside from a double helix, DNA folds into non-canonical structures, one of which is the guanine quadruplex. Cationic porphyrins bind guanine quadruplexes, but the effects of ligand binding on the structure of guanine quadruplexes with more than four
An overview is given of recent work on the determination of inelastic mean free paths, mean escape depths, information depths, and effective attenuation lengths for applications in hard X-ray photoelectron spectroscopy (HAXPES). Sources of data are
Christopher Reddy, Stephen Wise, Lane C. Sander, Jacolin Murray
Following an open meeting entitled, "Hydrocarbon Chemistry QA/QC," at the 2014 Gulf of Mexico Oil Spill and Ecosystem Science Conference in Mobile, Alabama, the Gulf of Mexico Research Initiative (GoMRI) initiated the Hydrocarbon Intercalibration
Fernanda I. Colabuono, Stacy Schuur, Kevin Huncik, Satie Taniguchi, Petry V. Maria, John Kucklick, Rosalinda C. Montone
Seabirds play an important role as top consumers in the food web and can be used as biomonitors of exposure to pollutants. Contamination studies on seabirds involving non-destructive sampling methods are of considerable importance, allowing better
Ryan C. Nieuwendaal, Krishna Jayachandrababu, Ross Verploegh, Johannes Leisen, David Sholl, Sankar Nair
Mixed-linker zeolitic imidazolate frameworks (ZIFs) are nanoporous materials that exhibit continuous and controllable tunability of properties like effective pore size, hydrophobicity and organophilicity. The structure of mixed-linker ZIFs has been studied
We describe an approach for creating a cost-effective, field deployable dynamic pressure standard based on measurement of fundamental quantum properties of molecular systems. From the linewidth and intensities of ro-vibrational transitions we plan on
Liquid fuels aboard high-performance aircraft currently fulfill the role of both the propellant and the heat sink for regenerative cooling. The fuels themselves have now reached their thermal capacity for effective cooling, and any additional heat load
The discriminative potential of an ion trap mobility spectrometer (ITMS) for trace detection of illicit narcotics relative to environmental background was investigated with a receiver operator characteristic (ROC) curve framework. The ITMS response of
Patrick F. Egan, Jack A. Stone Jr., Jacob E. Ricker, Jay H. Hendricks
We have developed a new low-pressure sensor which is based on the measurement of (nitrogen) gas refractivity inside a Fabry-Perot (FP) cavity. We compare pressure determinations via this laser refractometer to that of well-established ultrasonic manometers
Anthony P. Kotula, Angela R. Hight Walker, Kalman D. Migler
We perform Raman spectroscopic measurements on normal alkanes (C nH 2n+2) with 21 {less than or equal to} n {less than or equal to} 60 with a specific focus on the conformational disorder that occurs below the melt temperature. We employ a three-state
In recent years microwave-induced combustion (MIC) has proven a robust sample preparation technique for difficult-to-digest samples containing high carbon content, especially for halogens and sulfur. NIST has applied the MIC methodology in combination with