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There is a variety of small-molecule species (e.g., tackifiers, plasticizers, oligosaccharides) the size-based characterization of which is of considerable scientific and industrial importance. Likewise, quantitation of the amount of oligomers in a polymer
James Radney, Xiaofei Ma, Keith A. Gillis, Michael R. Zachariah, Joseph T. Hodges, Christopher D. Zangmeister
The optical properties of atmospheric aerosols vary widely, being dependent upon particle composition, morphology and mixing state. This diversity and complexity of aerosols motivates measurement techniques that can discriminate and quantify a variety of
Basudev Lahiri, Glenn E. Holland, Vladimir A. Aksyuk, Andrea Centrone
The collective oscillation of conduction electrons, responsible for the LSPRs, enables engineering nanomaterials by tuning their optical response from the visible to THz as a function of nanostructure size, shape and environment. While theoretical
Rebecca A. Zangmeister, Todd A. Morris, Michael J. Tarlov
Current interest in melanin films derived from the autoxidation of dopamine stems from their use as a universal adhesion layer. Here we report chemical and physical characterization of polydopamine films deposited on gold surfaces from stirred basic
Kristine A. Bertness, Mark W. Raynor, Kevin C. Cossel, Florian B. Adler, Jun Ye
The analysis of water vapor impurity is important in a number of specialty gas applications. However the main driver for the development and advancement of trace H 2O analysis techniques has been the microelectronics industry. The International Technology
Greg B. Rieker, Fabrizio R. Giorgetta, William C. Swann, Ian R. Coddington, Laura C. Sinclair, Christopher L. Cromer, Esther Baumann, Alexander M. Zolot, Nathan R. Newbury
Frequency-comb spectroscopy in the near-infrared is used to measure atmospheric CO2 and H2O concentrations over a 2-km outdoor open-air path. This technique shows promise for measurements over length scales between point sensors and satellite systems.
A program, called PAM_C2v_2tops, for fitting the high-resolution torsion-rotation spectra of molecules with two equivalent methyl rotors and C2v symmetry at equilibrium is described and applied to the spectrum of acetone [(CH3)2CO]. The G36 permutation
Vladimir L. Orkin, Victor Khamaganov, E. E. Kasimovskaya, A G. Guschin
Rate constants for the gas phase reactions of OH radicals with three partially halogenated alkanes, CHCl3 (kMC), CHFClCFCl2 (k122a), and CH2CFCl2 (k132c), were measured using a discharge flow electron paramagnetic resonance technique over the temperature
buchanan Evan, Patrick Walsh, David F. Plusquellic, Timothy Zwier
Vibrationally and rotationally resolved electronic spectra of 1,2-diphenoxyethane (C6H5-O-CH2-CH2-O-C6H5) are reported for the isolated molecule under jet-cooled conditions. The spectra demonstrate that the two excited surfaces are within a few cm-1 of one
Raina V. Gough, Jason A. Widegren, Thomas J. Bruno
Recent surrogate diesel fuel mixture development identified the need for a multiply-substituted, low cetane number, high molecular mass monocycloalkane component. On the basis of a thermophysical property evaluation and prediction, 1,3,5
Thomas P. Forbes, Timothy M. Brewer, John G. Gillen
We present the investigation of droplet charging and charge transmission characteristics of an electro-flow focusing nozzle for desorption-based ambient ionization mass spectrometry. The electro-flow focusing geometry utilizes a concentrically flowing gas
John M. Pettibone, William A. Osborn, Konrad Rykaczewski, Albert A. Talin, John E. Bonevich, Jeffrey W. Hudgens
The unique properties of metallic nanoclusters are attractive for numerous commercial and industrial applications but are generally less stable than nanocrystals. Thus, developing methodologies for stabilizing nanoclusters and retaining their enhanced
Lane C. Sander, Mary Bedner, David L. Duewer, Katrice A. Lippa, Melissa M. Phillips, Karen W. Phinney, Catherine A. Rimmer, Michele M. Schantz, Katherine E. Sharpless, Susan Tai, Jeanice M. Brown Thomas, Stephen A. Wise, Laura J. Wood, J. M. Betz, Paul M. Coates
The National Institute of Standards and Technology administers quality assurance programs devoted to improving measurements of nutrients and related metabolites in foods, dietary supplements, and serum and plasma samples. These programs have been developed
Michael A. Nelson, John M. Ondov, Michael C. VanDerveer, Bruce A. Buchholz
Measurements of the 14C abundance in five samples of bis(2-ethylhexyl) phthalate (DEHP) isolated from Stilton cheese were made by Accelerator Mass Spectrometry (AMS) to determine the fraction of carbon originating from contemporary biogenic sources. DEHP
Michele M. Schantz, Lane C. Sander, Katherine E. Sharpless, Stephen A. Wise, James H. Yen, A. NguyenPho, Joseph M. Betz
As part of a collaboration with the National Institutes of Healths Office of Dietary Supplements and the Food and Drug Administrations Center for Drug Evaluation and Research, the National Institute of Standards and Technology has developed Standard
Nathan R. Newbury, Esther Baumann, Ian R. Coddington, Fabrizio R. Giorgetta, Greg B. Rieker, Laura C. Sinclair, William C. Swann, Alexander M. Zolot
Frequency combs have enabled a wide range of applications because of their unique combination of coherence and broad bandwidth. The comb provides 100,000's of comb teeth at precise, well-known optical frequencies that can support broadband accurate
Katrice A. Lippa, Laura J. Wood, Stefan D. Leigh, Nathanael A. Heckert
This interlaboratory study was uniquely designed to determine the effects of material granularity and sample processing techniques on the measurement variability (i.e. precision) of nutritional elements in various cereal materials. Participants were asked
Jeremie B. Courtois, Katarzyna E. Bielska, Joseph T. Hodges
We present a technique called differential cavity ring-down spectroscopy (D-CRDS) for reducing etaloning effects in a ring-down spectrometer. The method relies on alternately measuring and then subtracting intra-cavity losses associated with pairwise TEM00
Studies of climate change increasingly recognize the diverse influences exerted by monoterpenes in the atmosphere, including roles in particulates, ozone formation and oxidizing potential. Measurements of key monoterpenes suggest atmospheric amount-of
Asphaltenes, the heaviest and most polar fraction of crude oil, are responsible for the clogging of oil pipelines and of underground reservoir rocks. Asphaltenes are defined as a solubility class (toluene- or benzene-soluble, n-heptane insoluble), and a
Donald H. Atha, Niyatie Ammanamanchi, Mofiyin Obadina, Vytautas Reipa
Exposure of mammalian cells to oxidative stress can result in DNA damage that adversely affects many cell processes. We used bulk electrolysis in an electrochemical system and capillary electrophoresis (CE) to control and measure the effect of oxidative
Lu Deng, Edward W. Hagley, R Q. Wang, Charles W. Clark
Nonlinear optics has come a long way since the laser. This article reviews recent progress in coherent light-matter wave mixing and introduces some new concepts that will reframe future research directions.
Gar W. Truong, Kevin O. Douglass, Stephen E. Maxwell, Roger D. van Zee, David F. Plusquellic, Joseph T. Hodges, David A. Long
Challenging applications in trace gas analyses require high precision and acquisition rates.1-4 Many continuous-wave laser spectroscopy techniques exhibit significant sensitivity and potential;5 however, their scanning rates are slow because they rely upon