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Danyal J. Turkoglu, Robert G. Downing, Wangchun Chen, Dagistan Sahin, Jeremy C. Cook
Prompt gamma-ray activation analysis facilities with high neutron currents (≥109 s-1) generate triton-induced fast neutrons from 6Li-loaded collimators and beam stops at rates that soon damage gamma-ray detectors. We develop an alternative beam stop design
The eye-safe transmitter of a ground-based, integrated path differential absorption (IPDA) LIDAR (light detection and ranging) system is described and specified in detail. The transmitter is based on an actively stabilized, continuous-wave, single
The annellation theory method has been used to predict the locations of maximum absorbance (LMA) of the ultravioletvisible (UV-Vis) spectral bands in the group of polycyclic aromatic hydrocarbons (PAHs) C24H14 (dibenzo and naphtho)derivatives of
Size-exclusion chromatography (SEC) has benefitted from commercially-available on-line viscometers for thirty years now. Initial (and continued) interest was mostly in applying the universal calibration concept to obtain molar mass averages and
Vladimir L. Orkin, James B. Burkholder, S. P. Sander, J. P. D. Abbatt D. Abbatt, J. R. Barker, Robert E. Huie, C E. Kolb, Michael J. Kurylo III, David M. Wilmouth, P. H. Wine
Walter B. Wilson, Lane C. Sander, M. J. Lopez de Alda, Milton Lee, Stephen A. Wise
Retention indices for 79 alkyl-substituted polycyclic aromatic sulfur heterocycles (PASHs) were determined by using reversed-phase liquid chromatography (LC) on a monomeric and polymeric octadecylsilane (C18) stationary phase. Molecular shape parameters
Walter B. Wilson, Lane C. Sander, M. J. Lopez de Alda, Milton Lee, Stephen A. Wise
Retention indices for 70 polycyclic aromatic sulfur heterocycles (PASHs) were determined using reversed-phase liquid chromatography (LC) on a monomeric and a polymeric C18 stationary phase. Molecular shape parameters [length, breadth, thickness (T), and
To help optimize ion mobility spectrometry (IMS) for the detection of inorganic explosives, time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used to study the thermal desorption behavior of ammonium nitrate (NH4NO3) and potassium perchlorate
Sergey P. Belov, Alexandr V. Lapinov, Arthur A. Mescheryakov, Jon T. Hougen, Li-Hong Xu
This paper presents an explanation based on torsionally mediated proton-spinoverall-rotation interaction for the observation of doublet hyperfine splittings in some Lamb-dip sub-millimeter-wave transitions between ground-state torsion-rotation states of E
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