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Near 25 C, ab initio calculations of the zero-density viscosity of helium gas eta_He have an uncertainty of approximately 0.001 %, which is 1/40th of the uncertainty of the best measurements. The uncertainties of the published calculations for neon [Bich
Shonali Nazare, Jeffrey W. Gilman, Mauro Zammarano, Luke Haverhals, W.Matthew Reichert, Hugh De Long, Paul C. Trulove
In addition to being efficient solvents for biopolymers, several ionic liquids (ILs) have been shown to be effective solvents for synthetic polymers such as meta-aramids, i.e., Nomex ® (1-5). In this report, meta-aramid/cotton composites are generated by
Stacy S. Schuur, Paul R. Becker, Sylvain Berail, Russell D. Day, Olivier F. Donard, Keith A. Hobson, Amanda J. Moors, Rebecca S. Pugh, Lauren B. Rust, David G. Roseneau
Since 1999, the Seabird Tissue Archival and Monitoring Project (STAMP) has collected, banked, and analyzed seabird eggs using established protocols to monitor chlorinated pesticides, polychlorinated biphenyls (PCBs), brominated flame retardants, and
Additive packages are used with aviation kerosenes to achieve performance enhancements such as higher or lower operating temperatures or increased lubricity. An additive used to increase operating temperatures for heat sink applications is the +100
Nicholas Ritchie, Dale E. Newbury, Jeffrey M. Davis
The accuracy and precision of x-ray intensity measurements with an silicon drift detector (SDD) are compared with the same measurements performed on a wavelength spectrometer (WDS) for a variety of elements in a variety of materials. In cases of major (> 0
There are now a large number of papers in the spectroscopic literature which make use of multiple-valued (frequently double-valued) coordinate systems and the associated multiple-groups of the permutation-inversion group to deal with the symmetry
The solubility of water in 1-octanol was measured from 2 °C to 96 °C by coulometric Karl Fischer titration. The mass fraction solubility at 25 ° was found to be (48.91 ± 0.13) mg/g. Experiments also indicated the existence of a pseudo-equilibrium state
A rarely documented, yet industrially popular, approach to the size-exclusion chromatography (SEC) and related analysis of polymers that do not dissolve in common solvents (i.e., those solvents that are employed as mobile phases in high-throughput SEC
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