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Measurements were carried out to obtain thermal signatures of several ammonium nitrate/fuel (ANF) mixtures, using a laser-heating technique referred to as the laser-driven thermal reactor (LDTR). The mixtures were ammonium nitrate (AN)/kerosene, AN
One material attribute for nuclear forensics is material age. 241Pu is almost always present in uranium- and plutonium-based nuclear weapons, which pose the greatest threat to our security. The in-growth of 241Am due to the decay of 241Pu provides an
Timothy M. Brewer, Robert A. Fletcher, Matthew E. Staymates
Well characterized test materials are essential for validating the performance of current trace explosive detection systems. Explosive encapsulated microspheres have proven to be a valuable test material for trace explosive detection because their precise
David S. Simons, Christopher W. Szakal, William A. Osborn, Kyung Joong Kim
A pilot study for the quantitative surface analysis of multi-element alloy films has been performed by the Surface Analysis Working Group (SAWG) of the Consultative Committee for Amount of Substance (CCQM). The aim of this pilot study is to ensure the
Kurtis Sarafin, Ramon Durazo-Arvizu, Lu Tian, Karen W. Phinney, Susan Tai, Johanna Camara, Hubert W. Vesper, Joyce M. Merkel, Evan Green, Christopher T. Sempos, Stephen P. Brooks
Background: The Canadian Health Measures survey (CHMS) is an ongoing cross sectional national survey that includes a measure of 25-hydroxyvitamin D (25(OH)D) by Diasorin LIAISON immunoassay. The survey repeats approximately every two years with a new
Yauheni Paulechka, Vladimir Diky, Andrei F. Kazakov, Kenneth G. Kroenlein, Michael D. Frenkel
COSMO-SAC model was re-parameterized using the critically evaluated data generated by the NIST ThermoData Engine for vapor-liquid equilibria, excess enthalpies for binary mixtures, and activity coefficients of components of binary mixtures. The calculated
Metal-Organic Frameworks (MOFs) are three-dimensional coordination polymers that are well known for large pore surface area and their ability to adsorb molecules from both the gaseous and solution phases. In general, MOFs are electrically insulating, but
Yamil Simon, Daniel Abate-Pella, Dana M. Freund, Yan Ma, Adrian Hegeman, Yan Ma, Tobias Kind, O Fiehn, Birgit Beck, Emma L. Schymanski, Corey D. Broeckling, David V. Huhman, Lloyd W. Summer, Oleg V. Krokhin, Dwight R. Stoll
Identification of small molecules by liquid chromatography-mass spectrometry (LC-MS) could be greatly improved if the chromatographic retention information could be used along with mass spectral information to narrow down the lists of potential identities
Gery R. Stafford, Vijay Sethuraman, Deepa Vairavapandian, Manon C. Lafouresse, Tuhina Maark, Naba Karan, Shouheng Sun, Ugo Bertocci, Andrew Peterson, Pradeep Guduru
The effect of elastic strain on catalytic activity of platinum (Pt) towards oxygen reduction reaction (ORR) is investigated through de-alloyed Pt-Cu thin films; stress evolution in the de-alloyed layer and the mass of the Cu removed are measured in real
Jeffrey A. Manion, David A. Sheen, Iftikhar A. Awan
Presented is a combined experimental and modeling study of the kinetics of the reactions of H and CH3 with n-butane, a representative aliphatic fuel. Abstraction of H from n-alkane fuels creates alkyl radicals that rapidly decompose at high temperatures to
We describe an apparatus to measure the speed of sound of gas samples at temperatures from 265 K to 500 K with pressures up to 40 MPa. The speed of sound is determined from the frequency of the three lowest-order radial resonance modes for the gas in a
Mixtures of small gaseous hydrocarbons with longer chain hydrocarbons are of interest to the natural gas industry. In particular, binary mixtures of nonane are of particular interest, as nonane was just incorporated into the GERG-2008 equation of state
Stephen A. Wise, Lane C. Sander, Michele M. Schantz
Since identified as priority pollutants by the U.S. Environmental Protection Agency (EPA) in 1979, the 16 EPA polycyclic aromatic hydrocarbons (PAHs) have been a key motivation for analytical methods development for the determination of PAHs. In this
Due to the distinctive mass spectral patterns caused by the presence of chlorine and bromine in a molecule, interpretation of a mass spectrum can be much easier if the results of the relative isotopic concentrations are known. The following table provides
The interpretation of results from chromatographic measurements can often be augmented with an appropriate mathematical treatment of the solute retention that is observed. The goal of treatment is to make the resulting metric as independent of the
The following table provides practical information to allow the design and implementation of radiation protection in laboratory and industrial environments. Additional information and details can be found in the references.
Solvents that are commonly used in high performance liquid chromatography frequently have inherent chemical instabilities that must be considered when designing an analysis, or in the interpretation of results [1-4] . In many cases, such solvents are
It is important to place in perspective the relative ionizing radiation dose acquired in common laboratory settings. The most commonly encountered source is a 63Ni source used in gas chromatographic electron captures detectors and in ion mobility
Rick L. Paul, Rabia Oflaz, Jan Kucera, J W Bennett, E. A. De Nadai Fernandes, M. Kubesova, M. A. Bacchi, A. J. Stopic, R. E. Sturgeon, P. Grinberg
Instrumental neutron activation analysis with both relative and k0 standardization was used in four experienced laboratories to determine element mass fractions in single-wall carbon nanotube certified reference material (CRM) SWCNT-1. Results obtained
Catherine Rimmer, Leila Saldanha, Johanna Dwyer, Karen Andrews, Regan Bailey, Joseph Betz, Vicki Burt, Rebecca Costello, Nancy Emenaker, Jaime Gahche, J. Harnly, Constance Hardy, Pamela R. Pehrsson
Dietary supplement databases are needed to calculate total dietary intakes from foods and supplements. Analytically verified databases are necessary for commonly consumed products as estimates of intakes are used in guiding public policy decisions. The
Rick L. Paul, Dagistan NMN Sahin, Jeremy C. Cook, Christoph W. Brocker, Richard M. Lindstrom, Donna J. O'Kelly
A new instrument for cold neutron prompt gamma-ray activation analysis (CNPGAA) has been designed and constructed as part of the recent expansion of the cold neutron guide hall at the NIST Center for Neutron Research (NCNR). Located on neutron guide NGD
Oxidatively induced damage caused by free radicals and other DNA-damaging agents generate a plethora of products in DNA of living organisms. There is mounting evidence for the involvement of this type of damage in the etiology of numerous diseases
Shotgun lipidomics is a well suited approach to monitor lipid alterations due to its ability to scan for varying lipid types on a global, class and individual species level. However, the ability to perform high-throughput shotgun lipidomics has remained
Richard A. Perkins, Marcia L. Huber, Marc J. Assael, Efthimia K. Mihailidou, Sofia K. Mylona, Evita J. Sykioti
This article summarizes the correlation procedures developed for IUPAC Project 2012-040-1-100 (Reference correlations for the thermal conductivity and viscosity of fluids over extended range of conditions (vapor, liquid and supercritical region)). This