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Sample Concentration and Processing Sample concentration is a common step in sample preparation prior to analysis that is performed to increase method sensitivity or to exchange solvent environment. Sample concentration can be thought of as a separation
Soxhlet extraction is one of several sample preparation methods that can be used to transfer targeted analytes from a sample matrix into a solvent, to permit subsequent analysis. With Soxhlet extraction, samples are repeatedly extracted with solvent
The ability to assess analytical performance is a fundamental component of measurement science. Ultimately, measurement quality depends on the proper function of instrumentation in combination with appropriate methods. Evidence of proper function is
The determination of mass is a fundamental component in quantitative analysis, and weighing accuracy is an important factor for most applications. This presentation will highlight the use of different types of analytical balances and will demonstrate
Although volumetric measurements are usually less accurate than gravimetric based measurements, volumetric measurements are still in common use due to the convenience, and often higher throughput, that may be afforded by automatic pipettes. Analysts should
Chromatography is an example of a process by which a mixture is separated into at least two fractions with different compositions. Other separation methods exist, such as distillation, recrystallization, and extraction. Chromatography is used to analyze
Walter B. Wilson, Lane C. Sander, Jorge O. Ona Ruales, Stephanie Mossner, Leonard M. Sidisky, Milton Lee, Stephen A. Wise
Retention indices for 10 sets of alkyl-substituted polycyclic aromatic sulfur heterocycles (PASHs) isomers (total of 80 PASHs) were determined using gas chromatography with three different stationary phases: a 50% phenyl phase, a 50% liquid crystalline
Walter B. Wilson, Lane C. Sander, Jorge O. Ona Ruales, Leonard M. Sidisky, Milton Lee, Stephen A. Wise
Retention indices for 70 polycyclic aromatic sulfur heterocycles (PASHs) were determined using gas chromatography with three different stationary phases: a 50% phenyl phase, a 50% liquid crystalline dimethylpolysiloxane (LC-DMPS) phase, and an ionic liquid
Thomas A. Blake, Jean-Marie Flaud, Walter J. Lafferty
A Fourier transform spectrum of sulfur dioxide 33S16O2 has been recorded in the 18.3 µm spectral region at a resolution of 0.002 cm-1 using a Bruker IFS 125HR spectrometer leading to the observation of the ν2 and 2ν2- ν2 vibrational bands of the 33S16O2
Venturi-assisted ENTrainment and Ionization (VENTI) was developed herein, demonstrating efficient entrainment, collection, and transport of remotely sampled vapors, aerosols, and dust particulate for real-time mass spectrometry (MS) detection. Integrating
Kevin C. Cossel, Eleanor M. Waxman, Ian A. Finneran, Geoffery A. Blake, Jun Ye, Nathan R. Newbury
Broadband spectroscopy is an invaluable tool for measuring multiple gas-phase species simultaneously. In this work we review current applications for broad-band spectroscopy. We discuss components of broad-band spectroscopy including light sources
David A. Sheen, Werickson Fortunato de Carvalho Rocha, Katrice A. Lippa, Dan Bearden
Process quality control and reproducibility in emerging measurement fields such as metabolomics is normally assured by interlaboratory comparison testing. As a part of this testing process, spectral features from a spectroscopic method such as nuclear
Jeanita Pritchett, Katrice A. Lippa, Mary Bedner, Carolyn Q. Burdette, Johanna Camara, Brian E. Lang, Michael A. Nelson, Lane C. Sander, Lorna T. Sniegoski
The one week NIST-SIM chemical metrology training opportunity was designed to provide SIM NMI/DI laboratory personnel with in-depth classroom and hands-on laboratory experience for the implementation of isotope dilution/mass spectrometry (ID/MS) methods in
Norman A. Sanford, Paul T. Blanchard, Ryan M. White, Michael R. Vissers, Albert Davydov, D R. Diercks, David P. Pappas
Laser-assisted atom probe tomography (L-APT) was used to examine superconducting TiN/Ti/TiN trilayer films with nominal respective thicknesses of 5/5/5 (nm). The trilayers were deposited on Si substrates by reactive sputtering. Electron energy loss
Monique E. Johnson, Shannon Hanna, Antonio R. Montoro Bustos, Christopher M. Sims, Lindsay C. Elliott, Babak Nikoobakht, John T. Elliott, Richard D. Holbrook, Keana C. Scott, Karen E. Murphy, Elijah J. Petersen, Lee L. Yu, Bryant C. Nelson, Akshay Lingayat, Adrian C. Johnston
For environmental studies assessing uptake of orally ingested engineered nanoparticles (ENPs), a key step in ensuring accurate quantification of ingested ENPs is efficient separation of the organism from ENPs that are either nonspecifically adsorbed to the
David A. Long, Adam J. Fleisher, David F. Plusquellic, Joseph T. Hodges
An optical frequency comb generated with an electro-optic phase modulator and a chirped radiofrequency waveform is used to perform saturation spectroscopy on the D1 and D2 transitions of atomic potassium. With a comb tooth spacing of 2 MHz and a bandwidth
Jacob E. Ricker, Jay H. Hendricks, Thomas Bock, Prazak Dominik, Tokihiko Kobata, Jorge Torres, Irina Sadkovskaya
This report summarizes the Consultative Committee for Mass (CCM) key comparison CCM.P-K4.2012 for absolute pressure spanning the range of 1 Pa to 10 000 Pa. The comparison was completed via calibration of a transfer standard carried out at six NMIs during
Stacy Schuur, Paul R. Becker, Colleen E. Bryan Sallee, Rebecca Pugh, Jared Ragland, Jessica Reiner, Jennifer Hoguet, Michele M. Schantz
The USA's Marine Environmental Specimen Bank (ESB) has archived marine wildlife collections dating back to 1976. Numerous lessons have been learned including collecting the correct species and tissues for environmental contaminant monitoring, developing
Facile fabrication of nanostructured electrode arrays is critical for development of bimodal SERS and electrochemical biosensors. In this paper, the variation of applied potential at a polyaniline- coated Pt electrode is used to selectivity deposit Au on
With the technological advances of mass spectrometry (MS)-based platforms, clinical proteomics is one of the most rapidly growing areas in biomedical research. Urine proteomics has become a popular sub-discipline of clinical proteomics because it is an
Jinfa Ying, Frank Delaglio, Dennis Torchia, Adriaan Bax
Implementation of a new algorithm, SMILE, is described for reconstruction of non-uniformly sampled two-, three- and four-dimensional NMR data, which takes advantage of the known phases of the NMR spectrum and the exponential decay of underlying time domain
Kimberly N. Urness, Raina V. Gough, Jason A. Widegren, Thomas J. Bruno
Synthetic lubricants are widely used for applications that require high-thermal and oxidative stability. In order to facilitate new designs and applications for these fluids we are measuring a suite of thermophysical and transport properties for lubricant
The interaction between electrodeposition of Ni and electrolyte breakdown, namely the hydrogen evolution reaction (HER) via H3O+ and H2O reduction, was investigated under well-defined mass transport conditions using ultramicroelectrodes (UMEs) coupled
Ying Jin, Anthony Kotula, Angela R. Hight Walker, Kalman D. Migler, Young Jong Lee
We usemoving-window two-dimensional correlation spectroscopy (MW-2DCOS) for phase-specific Raman analysis of the n-alkane (C21H44) duringmelting from the crystalline solid phase to the intermediate rotator phase and to the amorphousmolten phase. In MW
Jorge O. Ona Ruales, Walter B. Wilson, Federica Nalin, Lane C. Sander, Patricia Schubert, Stephen A. Wise
A link between the aromatic character of polycyclic aromatic hydrocarbons (PAHs) and gas chromatography (GC) elution order in columns with a polysiloxane backbone in the stationary phase is reported for the first time. The aromatic character was calculated