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Thomas J. Bruno, George G. Anitescu, Lawrence L. Tavlarides
To develop efficient reactor and plant designs to optimize the process of biofuel production, thermophysical and chemical properties of various reactive mixtures as well as those of biofuel are required over wide range of conditions. In this study, the
Dan Bearden, Arezue F. Boroujerdi, Peter A. Lee, Giacomo R. DiTullio, Michael G. Janech, Sarah B. Vied
Nuclear magnetic resonance (NMR)-spectroscopy has been used to obtain metabolic profiles of the polar diatom Fragilariopsis cylindrus, leading to the identification of a novel metabolite in this organism. Initial results from an ongoing metabolomics study
Highly accurate spectroscopic models for O2 A-band absorption are required in numerous satellite- and ground-based remote sensing measurements of atmospheric greenhouse gases. In this study, we quantify the sensitivity of the calculated A-band transmission
Hydrodynamic chromatography (HDC) has experienced a resurgence in recent years for particle and polymer characterization due, principally, to its coupling to a multiplicity of physical detection methods. Coupled to light scattering (both multi-angle static
Recent studies have identified uncertainties in fuel diffusion coefficients as a source of significant uncertainty in combustion modeling. This paper presents accurate binary diffusion coefficients of linear hydrocarbons in helium and nitrogen at
Savelas A. Rabb, Lee L. Yu, Deborah S. Jacobs, Tinh Nguyen
Silica nanoparticles (nanosilica) are being utilized to enhance the mechanical performance of polymeric materials used in many industries. However, cumulative effects of ultraviolet (UV) radiation will degrade the polymeric molecules, resulting in a
The properties imparted, oftentimes synergistically, by the different components of copolymers and blends account for the widespread use of these in a variety of industrial products. Most often, however, processing and end-use of these materials
It is generally understood that DNA serves as the direct template that eventually encodes a protein responsible for biochemical function. Alterations of a protein after synthesis (post-translational modifications, PTMs) can play a large role in a proteins
Christopher W. Szakal, James McCarthy, Andrew R. Konicek, Kacie Louis, Benjamin Yezer, Andrew A. Herzing, Robert Hamers, Richard D. Holbrook
Despite best efforts at controlling nanoparticle (NP) surface chemistries, the environment surrounding nanomaterials is always changing and can impart a permanent chemical memory. We present a set of preparation and measurement methods to be used as the
Rick L. Paul, Adrien Couet, Arthur Motta, Robert Comstock
We propose a novel use of a non-destructive technique to quantitatively assess hydrogen concentration in zirconium alloys. The technique, called Cold Neutron Prompt Gamma Activation Analysis (CNPGAA), is based on measuring prompt gamma rays following the
Jennifer M. Lynch, Lily Ngai, Joanne Braun-McNeill, Larry Wood, Kelly Stewart, Steven O'Connell, John R. Kucklick
We compared the plasma concentration of 13 perfluorinated contaminants (PFCs) in five sea turtle species. Perfluorooctane sulfonate (PFOS) was predominant in most species, except hawksbills had higher concentrations of perfluorononanoate. Excluding
A users guide is presented for Standard Reference Material (SRM) 2569 Lead in Paint Films for Childrens Products. This SRM consists of paint films on coupons of polyester with the paint characterized for mass fraction of Pb, mass of Pb per unit area
Comprehensive two-dimensional gas chromatography (GCXGC) offers advantages over one-dimensional gas chromatography (GC) including, high peak capacity, signal enhancement, and structured chromatograms. These advantages have been exploited to solve several
Hydration of the β-MnO2 (110), (100), and (101) surfaces is investigated using a combination of periodic density functional theory and ab initio thermodynamics. Fully hydrated surfaces are found to be significantly more stable than the stoichiometric ones
William C. Davis, Lisa E. Kilpatrick, Eric L. Kilpatrick, Guillaume Ballihaut
Selenoprotein P (SePP) is a unique selenium-containing protein responsible for the transport and distribution of the essential trace element selenium (Se) through the human body with the concentration of SePP in human blood representing the most useful
Ashley B. Green, David M. Bunk, Paul A. Rudnick, Karen W. Phinney, Lisa E. Kilpatrick
The emergence of mass spectrometry-based proteomic platforms as a prominent technology utilized in biochemical and biomedical research has increased the need for high-quality MS measurements. To address this need, NIST Reference Material (RM) 8323 Yeast
Russell D. Day, David G. Roseneau, Sylvain Berail, Keith A. Hobson, O.F.X Donard, Stacy S. Schuur, Rebecca S. Pugh, Amanda J. Moors, Stephen E. Long, Paul R. Becker
Elevated mercury concentrations ([Hg]) were found in Alaskan seabird eggs (Uria spp.) from the coastal embayment of Norton Sound relative to insular colonies in the northern Bering Sea. Stable isotopes of Hg, carbon (C), and nitrogen (N) were measured in
Obstruction factor is a generic rubric under which are usually gathered the interparticle, intraparticle, stationary phase, and total obstruction factors, gamma(e), gamma(p), gamma(s), and gamma(t), respectively. These, in turn, affect longitudinal
Jianyuan Zhang, Fuhrer Tim, Wujun Fu, Jiechao Ge, Dan Bearden, Jerry Dallas, Duchamp James, Kenneth Walker, Hunter Champion, Hugo Azurmendi, Kim Harich, Harry C. Dorn
The encapsulation of clusters (or small molecules) in spheroidal fullerene cages provides a unique isolated environment that is important in describing their shape, dynamics, and physical properties. For the case of yttrium carbide clusters, we find that
Lan (. Li, Eric J. Cockayne, Laura Espinal, Winnie K. Wong-Ng
Manganese oxide OMS-2 material, also known as alpha-MnO2, exhibits CO2 sorption hysteresis at pressures > 7 bar. Our experiments show that the hysteretic behavior strongly depends on time, temperature and pressure. To understand the atomic structures and
Laura Espinal, Winnie K. Wong-Ng, Andrew J. Allen, Daniel W. Siderius, Chad R. Snyder, Eric J. Cockayne, Lan (. Li, James A. Kaduk, Anais E. Espinal, Steven L. Suib, Chun Chiu
A critical challenge in the development of novel carbon capture materials with engineered porous architectures is to understand and control the phenomenon of sorption hysteresis, whereby the path to adsorption of gas molecules by the porous host differs
Liquid chromatographic methods with atmospheric pressure chemical ionization mass spectrometry were developed for the determination of the vitamin D metabolites 25-hydroxyvitamin D2 (25(OH)D2), 25-hydroxyvitamin D3 (25(OH)D3), and 3-epi-25-hydroxyvitamin
Jessica L. Reiner, Jennifer M. Lynch, Michele M. Schantz, Steven O'Connell, Craig M. Butt, Scott Mabury, Jeff Small, Amila De Silva, Derek Muir, Amy D. Delinsky, Mark J. Strynar, Andrew B. Lindstrom, William K. Reagen, Michelle Malinsky, Sandra Schafer, Christiaan Kwadijk
Standard Reference Materials (SRMs) are homogeneous, well-characterized materials that are used to validate measurements and improve the quality of analytical data. The National Institute of Standards and Technology (NIST) has a wide range of SRMs that
Richard D. Holbrook, Jeffrey M. Davis, Keana C. Scott, Christopher W. Szakal
The ubiquitous presence of brominated flame retardants in humans, biota, and the environment has caused concerns about their toxicity, transformations, and persistence. Polymeric materials, which often are intercalated with include brominated flame