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Background: The National Institute of Standards and Technology (NIST), in collaboration with the National Institutes of Health Office of Dietary Supplements, established the first accuracy-based program for improving the comparability of vitamin D
The effect of finite beam extinction ratio on the precision and accuracy of cavity ring-down decay time constant measurements was examined using the frequency-agile, rapid scanning, cavity ring-down spectroscopy (FARS-CRDS) technique. This new approach to
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
Vivek M. Prabhu, Shrinivas Venkataraman, Ashlynn Lee, Yi Yan Yang, James Hedrick, Hareem Maune
In this study, a cholesterol functionalized aliphatic cyclic carbonate monomer, 2-(5-methyl-2-oxo-1,3-dioxane-5-carboxyloyloxy)ethyl carbamate (MTC-Chol) was synthesized. The organo-catalytic ring opening polymerization of MTC-Chol was accomplished by
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
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
Aim -- To type a set of 194 US African American, Caucasian,and Hispanic samples (self-declared ancestry) for 40 autosomal single nucleotide polymorphism (SNP) markers intended for human identification purposes. Methods -- Genotyping was performed on an
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
Susan M. Ballou, Michael Garris, Anthony Clay, Joi Dickerson, Peter T. Higgins, Lisa Jackson, Joe Morrissey, Beth Owens, Joe Polski, Janet Hoin, Leo Norton, Melissa Taylor
This is one of a series of documents prepared by the Latent Print Automated Fingerprint Identification System (AFIS) Interoperability Working Group. The purpose of these documents is to provide guidance and a framework to those involved in the
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
Rick L. Paul, Hsiu-Wen Wang, David J. Wesolowski, Thomas E. Proffen, Lucus Vicek, Wei Wang, Lawrence F. Allard, Alexander I. Kolesnikov, Mikhail Feygenson, Lawrence M. Anovitz
The structure of SnO2 nanoparticles (avg. 5 nm diameter) with a few layers of water on the surface has been elucidated by atomic pair distribution function (PDF) methods using in situ neutron total scattering data and molecular dynamics (MD) simulations
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
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
Susan M. Ballou, Michael Garris, Anthony Clay, Joi Dickerson, Peter T. Higgins, Janet Hoin, Lisa Jackson, Mike Lesko, Joe Morrissey, Leo Norton, Beth Owens, Joe Polski, Melissa Taylor
This is one of a series of documents prepared by the Latent Print Automated Fingerprint Identification System (AFIS) Interoperability Working Group. The purpose of these documents is to provide guidance and a framework to those involved in the
Susan M. Ballou, Margaret C. Kline, Mark D. Stolorow, Melissa Taylor, Shannan Williams, Phylis S. Bamberger, Burney Yvette, Larry Brown, Cynthia E. Jones, Ralph Keaton, William Kiley, Karen Thiessen, Gerry LaPorte, Joseph Latta, Linda E. Ledray, Randy Nagy, Linda Schwind, Stephanie Stoiloff, Brian Ostrom
The report of the Technical Working Group on Biological Evidence Preservation offers guidance for individuals involved in the collection, examination, tracking, packaging, storing, and disposition of biological evidence. This may include crime scene
Elisabeth Mansfield, Seid M. Adem, John P. Keogh, Craig A. Aspinwall, Henry K. Hall
Phosphorylcholine (PC) based phospholipid bilayers have proven useful as capillary coating materials due to their inherent resistance to non-specific protein adsorption. The primary limitation of this important class of capillary coatings remains the
Vladimir L. Orkin, Victor Khamaganov, S N. Kozlov, Michael J. Kurylo III
Measurements of the rate constants for the gas phase reactions of OH radicals with bromoform (CHBr3) and epichlorohydrin (C3H5ClO) were performed using a flash photolysis resonance-fluorescence technique over the temperature range 230 K to 370 K. The
Si nanocrystals, terminated with cyclohexane and allylamine, were analyzed using analytical ultracentrifugation (AUC), dynamic light scattering (DLS) and transmission electron microscopy (TEM). We found that AUC yielded equivalent particle size
The National Institute of Standards and Technology (NIST) recently 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
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 fifth
Secondary organic aerosol (SOA) particles result from the condensation of oxidized volatile organic compounds (VOC) and consist of a complex mixture that resists a complete analysis. We present a simple methodology for determining the quantities of
Christopher Soles, Richard Kasica, Hae-Jeong Lee, Jae H. Sim, Sung-Il Lee, Ki-Bum Kim, Hyun-Mi Kim, Do Y. Yoon
Hydrogen silsesquioxane (HSQ) is an attractive electron-beam (e-beam) resist for sub-20 nm lithography due to its high resolution, excellent line-edge-roughness (LER), and good plasma etch resistance. However, the sensitivity and long-term stability of HSQ