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Catherine A. Rimmer, Melissa M. Phillips, Hendrik Emons, Jane Weitzel, John Budin, Donna Zink
At the 2011 AOAC International Annual Meeting, the Technical Divisions on Reference Materials (TDRM) and Laboratory Management (TDLM) arranged a workshop focused on the needs for and applications of reference materials in laboratory accreditation programs
Katrice A. Lippa, Kevin Bisceglia, A. Lynn Roberts
We report a streamlined procedure for the routine analysis of cocaine in municipal wastewater. By adding NaOH (to 0.025 M) and incubating wastewater samples at 55 °C for two hours, cocaine and its principal metabolites are quantitatively converted into
Thomas J. Bruno, Jessica L. Burger, Evgenii Baibourine
There is a great deal of interest in formulating oxygenated diesel fuels that produce low particulate emissions. In this paper, the fourth in a series of papers on the properties of mixtures of diesel fuel with oxygenating additives, we present the
Hae-Wook Yoo, Lee J. Richter, Hee-Tae Jung, Chris A. Michaels
We report surface plasmon polariton (SPP) mediated Raman microscopy on dielectric films in contact with a Ag layer at 785 nm with spatial resolution approaching the optical diffraction limit and reasonable spectral acquisition times. The excitation and
Michele M. Schantz, Adriaan van der Veen, Hugo Ent, Annaratia Baldan, Valnei Cunha, Romeu Daroda, Manuela Ulberth-Buchgraber, Brian E. Lang, Andrea Held, Ruth Hearn, Richard Brown, Paul Brewer
The main objective of the BIOREMA (Reference Materials for Biofuel Specifications) project is the development of two test materials (one bio-ethanol material and one biodiesel material) with well-established reference values. This paper describes the
Kenneth O. Patten, Victor Khamaganov, Vladimir L. Orkin, Steven L. Baughcum, Donald J. Wuebbles
The rate constant for the gas phase reaction of OH radicals with BTP (2-Bromo-3,3,3-trifluoropropene, CH2=CBrCF3) was measured using a flash photolysis resonance-fluorescence technique over the temperature range 220 K to 370 K. The Arrhenius plot was found
Esther Baumann, Fabrizio R. Giorgetta, William C. Swann, Alexander M. Zolot, Ian R. Coddington, Nathan R. Newbury
We demonstrate a high-accuracy dual-comb spectrometer centered at 3.4 υm. The amplitude and phase spectra of the P,, Q, and partial R branches of the methane Ņ3 band are measured at 25 to 100 MHz point spacing with resolution under 10 kHz and a signal-to
Joshua Sebree, David F. Plusquellic, Timothy Zwier
With the growing interest in the role naphthalene may play in planetary atmospheres and the interstellar medium, it is important to characterize other C10H8 structural isomers. These C10H8 isomers, once formed, may undergo an isomerization reaction to form
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