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Evaluation of chemical purity using quantitative 1H-nuclear magnetic resonance

September 28, 2016

Author(s)

Blaza Toman, Michael A. Nelson, Katrice A. Lippa

Chemical purity assessment using quantitative 1H-nuclear magnetic resonance spectroscopy is a method based on ratio references of mass and signal intensity of the analyte species to that of chemical standards of known purity. As such, it is an example of a

NIST/NIH Vitamin D Metabolites Quality Assurance Program Report of Participant Results: Summer 2014 Comparability Study(Exercise 9)

September 19, 2016

Author(s)

Mary Bedner, Susan Tai

The National Institute of Standards and Technology (NIST) has established a Vitamin D Metabolites Quality Assurance Program (VitDQAP) in collaboration with the National Institutes of Health (NIH) Office of Dietary Supplements. Participants in the ninth

NIST/NIH Vitamin D Metabolites Quality Assurance Program Report of Participant Results: Winter 2014 Comparability Study (Exercise 8)

September 19, 2016

Author(s)

Mary Bedner, Susan Tai

NIST/NIH Vitamin D Metabolites Quality Assurance Program Report of Participant Results: Winter 2015 Comparability Study (Exercise 10)

September 19, 2016

Author(s)

Mary Bedner

in situ methods for monitoring silver nanoparticle sulfidation in simulated waters

September 16, 2016

Author(s)

John M. Pettibone, Jingyu Liu

To probe the transformation pathways of metallic nanomaterials, measurement tools capable of detecting and characterizing the broad distribution of products with limited perturbation is ideal. Thus, we employed a suite of in situ measurements (single

Application of the advanced distillation curve method for the characterization of two alternative transportation fuels prepared from the pyrolysis of polyethylene bags*

September 15, 2016

Author(s)

Thomas J. Bruno, Megan E. Harries, B. K. Sharma, Bidhya Kunwar

The properties of alternative fuels must be evaluated to determine their suitability for use in existing engines, either as blends with conventional petroleum products or as stand-alone substitutions (that is, drop in replacements). Alternative fuels made

Development of Standard Reference Materials to Support Assessments of Iodine Status in Nutrition and Human Health.

August 17, 2016

Author(s)

Stephen E. Long, Brittany L. Kassim, Ashley S. Boggs-Russell, Susan Tai, Stephen A. Wise

Iodine deficiency remains a significant global public health challenge. Analytical measurements are therefore made routinely to assess iodine intake from food and supplements, public health status and trends. The National Institute of Standards and

U.S. domestic cats as sentinels for perfluoroalkyl substances: Possible linkages with housing, obesity, and disease

August 2, 2016

Author(s)

Jessica L. Reiner, Andrew B. Lindstrom, Phillip C. Bost, Janice Dye, Jerry Zweigenbaum, Mark J. Strynar

Perfluoroalkyl substances (PFAS), such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), are persistent, globally distributed, anthropogenic compounds. The primary source(s) for human exposure are not well understood although within

Retention behavior of alkyl-substituted polycyclic aromatic sulfur heterocycles in reversed-phase liquid chromatography

July 24, 2016

Author(s)

Walter B. Wilson, Lane C. Sander, M. J. Lopez de Alda, Milton Lee, Stephen A. Wise

Retention indices for 79 alkyl-substituted polycyclic aromatic sulfur heterocycles (PASHs) were determined by using reversed-phase liquid chromatography (LC) on a monomeric and polymeric octadecylsilane (C18) stationary phase. Molecular shape parameters

Retention behavior of isomeric polycyclic aromatic sulfur heterocycles in reversed-phase liquid chromatography

July 24, 2016

Author(s)

Walter B. Wilson, Lane C. Sander, M. J. Lopez de Alda, Milton Lee, Stephen A. Wise

Retention indices for 70 polycyclic aromatic sulfur heterocycles (PASHs) were determined using reversed-phase liquid chromatography (LC) on a monomeric and a polymeric C18 stationary phase. Molecular shape parameters [length, breadth, thickness (T), and

An azeotropic cross-linked styrene-methacrylate network formed through rapid visible-light photo- polymerization

July 15, 2016

Author(s)

Yin Yang, Aaron A. Urbas, Andres Gonzalez-Bonet, Richard J. Sheridan, Jonathan E. Seppala, Kathryn L. Beers, Jirun Sun

A system containing well-defined functional material, a clinically practical procedure to make the material in situ, and proper analytical tools for chemical structure and kinetic studies is appealing, but currently unavailable. Herein, we introduce an all

Psychrometric Properties of Humid Air from Multi-Fluid Helmholtz-Free-Energy-Explicit Models

July 11, 2016

Author(s)

Ian H. Bell, Eric W. Lemmon, Allan H. Harvey

Psychrometric properties of humid air are widely used in the analysis and modeling of thermal systems. In this work we present a method for obtaining these properties from the multi-fluid mixture formulation forming the so-called GERG mixture model. This

LABORATORY FILTER MEDIA

June 1, 2016

Author(s)

Thomas J. Bruno

Filtration is the physical separation of a component or components (which may be solid, liquid, gel, etc.) from a matrix stream (which is usually a fluid), without causing any other changes such as chemical reactions. In the laboratory, filtration is most

Summary of results from the 2014/2015 Hydrocarbon Intercalibration Experiment (HIE)

May 27, 2016

Author(s)

Christopher Reddy, Stephen Wise, Lane C. Sander, Jacolin Murray

Following an open meeting entitled, "Hydrocarbon Chemistry QA/QC," at the 2014 Gulf of Mexico Oil Spill and Ecosystem Science Conference in Mobile, Alabama, the Gulf of Mexico Research Initiative (GoMRI) initiated the Hydrocarbon Intercalibration

Partial oxidation of step-bound water leads to anomalous pH effects on metal electrode step-edges

May 25, 2016

Author(s)

Kathleen Schwarz, Bingjun Xu, Yushan Yan, Ravishankar Sundararaman

The design of better heterogeneous catalysts for applications such as fuel cells and electrolyzers requires a mechanistic understanding of electrocatalytic reactions and the dependence of their activity on operating conditions such as pH. A satisfactory

Towards a dynamic pressure standard based on laser absorption spectroscopy

May 20, 2016

Author(s)

Kevin O. Douglass, Douglas A. Olson

We describe an approach for creating a cost-effective, field deployable dynamic pressure standard based on measurement of fundamental quantum properties of molecular systems. From the linewidth and intensities of ro-vibrational transitions we plan on

Mass Spectrometry of Analytical Derivatives. 2. Ortho and Para Effects in Electron Ionization Mass Spectra of Derivatives of Hydroxyl, Mercapto and Amino Benzoic Acids

May 1, 2016

Author(s)

Nino G. Todua, Anzor I. Mikaia

Derivatives requiring either anhydrous or aqueous reaction conditions were prepared for robust and reliable gas chromatography mass spectrometry (GC-MS) characterization of hydroxyl, mercapto, and amino benzoic acids. Methylation and trialkylsilylation

Speed of Sound Measurements in (Argon + Carbon Dioxide) over the Temperature Range from (275 to 500) K at Pressures up to 8 MPa

March 23, 2016

Author(s)

Mark O. McLinden, Richard A. Perkins, Robin Wegge, Markus Richter, Roland Span

The speed of sound of two (argon + carbon dioxide) mixtures was measured over the temperature range from (275 to 500) K with pressures up to 8 MPa utilizing a spherical acoustic resonator. The compositions of the gravimetrically prepared mixtures were (0

Predicting Structures of Ru-Centered Dyes: A Computational Screening Tool

March 16, 2016

Author(s)

Lisa A. Fredin, Thomas C. Allison

Dye-sensitized solar cells (DSCs) represent a viable means for harvesting solar energy to produce electrical power. Though a number of light harvesting dyes are in use, the search continues for more efficient and effective compounds to make commercially

Analysis of Human Plasma Metabolites across Different Liquid Chromatography - Mass Spectrometry Platforms

March 15, 2016

Author(s)

Kelly H. Telu, Xinjian Yan, William E. Wallace, Stephen Stein, Yamil Simon

The development of increasingly sensitive analytical techniques has renewed interest in global metabolite profiling, i.e., the semi-quantitative monitoring of all the chemical constituents of biological fluids. In this work, global metabolite profiles of

Method Validation and Standards in Hydrogen/Deuterium Exchange Mass Spectrometry

March 1, 2016

Author(s)

Jeffrey W. Hudgens, Richard Y. Huang, Emma D'Ambro

The chapter examines method validation and measurement standards for measuring protein dynamics by hydrogen/deuterium exchange mass spectrometry. Topics examined include the rationale for a reference measurement system for HDX-MS, attaining high accuracy

Field Portable Low Temperature Porous Layer Open Tubular Cryoadsorption Headspace Sampling and Analysis Part II: Applications*

February 16, 2016

Author(s)

Megan Harries, Santiago Bukovsky-Reyes, Thomas J. Bruno

This paper details the sampling methods used with the field portable PLOT-cryoadsorption (PLOT-cryo) approach, described in Part I of this two-part series, applied to several analytes of interest. We conducted tests with coumarin and 2,4,6-trinitrotoluene

Thermodynamic Properties of Polycyclic Aromatic Hydrocarbons

December 16, 2015

Author(s)

Thomas C. Allison, Donald R. Burgess Jr.

Polycyclic aromatic hydrocarbons (PAHs) are molecules that exist on earth due to natural and man-made causes. They are a significant health concern as many PAH compounds are known to be carcinogenic. PAHs are generally thermodynamically stable and

Particle Fabrication Using Inkjet Printing onto Hydrophobic Surfaces for Optimization and Calibration of Trace Contraband Detection Sensors

November 24, 2015

Author(s)

John G. Gillen, Marcela N. Najarro, Matthew E. Staymates, Scott A. Wight, Marlon L. Walker, Jennifer R. Verkouteren, Eric S. Windsor, Aaron A. Urbas

A method has been developed to fabricate patterned arrays of micrometer-sized monodisperse solid particles of ammonium nitrate on hydrophobic silicon surfaces using inkjet printing. The method relies on dispensing one or more microdrops (typically 50 pL

First far-infrared high resolution analysis of the nu6 band of phosgene 35Cl2CO and 35Cl37CLCO

November 2, 2015

Author(s)

Walter J. Lafferty

A Fourier transform spectrum of phosgene (Cl2CO) has been recorded in the 22.5 μm spectral region at a resolution of 0.00102 cm-1 using a Bruker IFS125HR spectrometer coupled with synchrotron radiation leading to the observation of the ν6 vibrational bands