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Lisa E. Kilpatrick, Pedatsur Neta, Xiaoyu Yang, Yamil Simon, Yuxue Liang, Stephen E. Stein
Tandem mass spectra of peptide ions, acquired in shotgun proteomic studies of selected proteins, tissues, and organisms, commonly include prominent peaks that cannot be assigned to the known fragmentation product ions (y, b, a, neutral losses). In many
Karen W. Phinney, Mary Bedner, Susan Tai, Veronica V. Vamathevan, Lane C. Sander, Katherine E. Sharpless, Stephen A. Wise
The National Institute of Standards and Technology (NIST), in collaboration with the National Institutes of Healths Office of Dietary Supplements (NIH-ODS) has developed a Standard Reference Material (SRM) for the determination of 25-hydroxyvitamin D [25
Recent metabolomics research on the temperature-dependent coral pathogen Vibrio coralliilyticus has led to the discovery of several compounds produced by the organism as a response to high-density, low nutrient growing conditions. Three compounds
Values of the Auger parameter are presented for 42 elemental solids. These values were determined from evaluated Auger-electron kinetic energies and photoelectron binding energies (BEs). Small adjustments were made to earlier values of photoelectron BEs to
Eduard Rocas, Juan C. Collado Gomez, Jordi Mateu, Nate Orloff, James Booth, Juan M. O'C allaghan
"This work evaluates the microwave nonlinear properties and tuning at RF frequencies of ferroelectric Ba0.3Sr0.7TiO3 thin-films by on-wafer measurements of the second and third-order harmonics and intermodulation products of several coplanar transmission
Paul C. DeRose, Melody V. Smith, Klaus Mielenz, Jeffrey R. Anderson, Gary W. Kramer
Standard Reference Material (SRM) 2943 is a cuvette-shaped, Cu0ion-doped glass, recommended for use for relative spectral correction of emission and day-to-day performance verification of steady-state florescence spectrometers. Properties of this standard
Nicholas W. Ritchie, Dale E. Newbury, Abigail P. Lindstrom
Artifacts are the nemesis of trace element analysis in electron-excited energy dispersive x-ray spectrometry. Peaks which result from non-ideal behavior in the detector or sample can fool even an experience microanalyst into believing that they have trace
Carbon materials typically have a high density of unpaired electronic spins but the exact nature of the defect sites that give rise to their magnetic properties are not yet well understood. In this work, the paramagnetic interactions between the unpaired
Lane C. Sander, Mary Bedner, Michael C. Tims, James H. Yen, David L. Duewer, Barbara J. Porter, Steven J. Christopher, Russell D. Day, Stephen E. Long, John L. Molloy, Karen E. Murphy, Brian E. Lang, Rachel A. Lieberman, Laura J. Wood, M. Payne, M. C. Roman, J. M. Betz, A. NguyenPho, Katherine E. Sharpless, Stephen A. Wise
A suite of three green tea-containing Standard Reference Materials (SRMs) has been issued by the National Institute of Standards and Technology (NIST). The materials are characterized for catechins, xanthine alkaloids, theanine, and toxic elements. As many
The northern diamondback terrapins (Malaclemys terrapin) wide geographic distribution, existence in a variety of habitats within the saltmarsh ecosystem, predatory foraging behavior and site fidelity make it an excellent indicator species for contaminant
John E. Schiel, Hua-Jun He, Karen W. Phinney, Jennifer Au
Glycosylation, the enzymatic addition of carbohydrates to a protein, is one of the most abundant post-translational modifications found in nature. There is variability in the number, location, and identity of glycans attached. As a result, a glycoprotein
Lane C. Sander, Michele M. Schantz, Stephen A. Wise
The term persistent organic pollutants (POPs) describes a broad range of anthropogenic compounds that are present in the environment. Persistent organic pollutants can be grouped into subclasses based on their original intended uses or chemical
Karen W. Phinney, Catherine A. Rimmer, Jeanice M. Brown Thomas, Lane C. Sander, Katherine E. Sharpless, Stephen A. Wise
Vitamins are essential to human health, and dietary supplements containing vitamins are widely used by individuals hoping to ensure they have adequate intake of these important nutrients. Measurement of vitamins in nutritional formulations is necessary to
Peter M. Johnson, Joonsung (. Yoon, Jennifer Y. Kelly, John A. Howarter, Christopher Stafford
In membranes for reverse osmosis and nanofiltration, the discriminating layers consist of an interfacially polymerized polyamide film on a porous support. For reverse osmosis membranes, the dominant commercial interfacial film is a crosslinked network
Ab initio thermodynamics was combined with density functional theory calculations to identify stable gamma- MnOOH (010) surface terminations in response to varying oxygen and water partial pressures. Within the range of accessible oxygen chemical
Kristine A. Bertness, Joshua R. Montague, Norman A. Sanford, Victor Bright, Charles T. Rogers
A variable-temperature, homodyne reflectometry measurement technique for detecting nanoscale mechanical motion has recently been developed. We have extended this technique to make the first all-electrical measurements of an ensemble of as-grown, c-axis
Daniel W. Bearden, Douglas W. Lowman, Lara J. West, Michael F. Wempe, Trevor D. Power, Harry E. Ensley, Ken Haynes, David L. Williams, Michael D. Kruppa
Glucan is a (1-3)-β-linked glucose polymer with (1-6)-β-linked side chains and a major component of fungal cell walls. Glucans provide structural integrity to the fungal cell wall. The nature of the (1-6)-β-linked side chain structure of fungal (1-3,1-6)-β
Matthew T. Hunley, Atul Bhangale, Santanu S. Kundu, Peter M. Johnson, Michael S. Waters, Richard Gross, Kathryn Beers
In situ, fiber optic-based Raman spectroscopy provided real time monitoring of enzyme-catalyzed ring-opening homo- and copolymerizations of ε-caprolactone (ε-CL) and δ-valerolactone (δ-VL). A custom designed reactor equipped with in situ fiber optic probe
Stephen A. Wise, Caroline Bergh, Giovanna Luongo, Conny Ostman
Twenty-two phthalate diesters and organophosphate triesters have been determined in Standard Reference Material (SRM) 2585 Organic Contaminants in House Dust. Ultrasonic assisted solvent extraction and Solid Phase Extraction on a Florisil adsorbent were
Gregory J. Dutton, Dan B. Dougherty, W. Jin, Janice E. Reutt-Robey, Steven W. Robey
Two photon photoemission (2PPE) and scanning tunneling spectroscopy (STS) were used to investigate C60 layers on Ag(111), focusing on unoccupied level assignments and, in particular, superatom molecular orbitals, SAMOs. SAMOs are diffuse levels that are
To support natural resource damage assessment (NRDA) in response to the Deep Water Horizon (DWH) oil spill in the Gulf of Mexico, a large number of coastal sediment and tissue (i.e., oysters) samples have been collected outside of the spill zone to define
Since the days of the alchemist, the observation that some substances have a smell while other substances do not has been a source of fascination. The sense of smell, or olfaction, is our least understood sense, however it is important for many human
Jessica L. Reiner, Karen W. Phinney, Jennifer M. Lynch
Perfluorinated compounds (PFCs) were measured in three National Institute of Standards and Technology Standard Reference Materials (SRMs 1950 Metabolites in Human Plasma, SRM 1957 Organic Contaminants in Non-fortified Human Serum, and SRM 1958 Organic
Adam M. Daly, Kevin O. Douglass, Laszlo C. Sarkozy, Justin L. Neill, Matt T. Muckle, Daniel P. Zaleski, Brooks H. Pate, Stephen G. Kukolich
Microwave spectra of the propiolic acid-formic acid, (Pro-FA) doubly hydrogen bonded complex were measured in the 1-21 GHz range. Rotational spectra for seven isotopomers were obtained and fit. For the parent isotopomer, a total of 138 a-dipole transitions