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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 eleventh
Cedric J. Powell, Wolfgang Werner, Alexander Shard, David G. Castner
We evaluated two methods for determining shell thicknesses of core-shell nanoparticles (NPs) by X-ray photoelectron spectroscopy (XPS). One of these methods had been developed for determining thicknesses of films on a planar substrate while the other was
The National Institute of Standards and Technology (NIST), at the request of the National Institute of Healths (NIHs) Office of Dietary Supplements (ODS) and in conjunction with the Centers for Disease Control and Prevention (CDC), initiated a third
Changran Liu, William S. McGivern, Jeffrey A. Manion, Hai Wang
Binary diffusion coefficients were measured for n-pentane, n-hexane and n-octane in helium and of n-pentane in nitrogen over the temperature range of (300 - 600) K, using reversed-flow gas chromatography. A generalized, analytical theory was proposed for
Kelly H. Telu, Xinjian Yan, William E. Wallace, Stephen Stein, Yamil Simon
Non-targeted global metabolite profiles of Standard Reference Material 1950, "Metabolites in Human Plasma," were obtained on five different liquid chromatography/mass spectrometry (LC/MS) instrument combinations using identically prepared samples
Michele M. Schantz, Carissa Powers, Schleicher Rosemary, Joseph Betz, Stephen A. Wise
The National Institute of Standards and Technology, in collaboration with the National Institutes of Health Office of Dietary Supplements and the Centers for Disease Control and Prevention, is conducting an accuracy-based program for improving 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 ninth
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 eighth
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 tenth
Cedric J. Powell, Aleksander Jablonski, Francesc Salvat, Angela Y. Lee
Version 4.0 of this database (SRD 64) provides values of differential elastic-scattering cross sections, total elastic-scattering cross sections, phase shifts, and transport cross sections for elements with atomic numbers from 1 to 96 and for electron
Richard A Livingston, Carol A. Grissom, Edward Vicenzi, Zoe Weldon-Yochim, Nicole Little, Janet Douglas, Alexandre Fowler, Cara Santelli, Dorothea Macholdt, Diana Ortiz-Montalvo, Stephanie S. Watson
Bluish black, highly adherent patches have been observed growing on the Seneca sandstone of the Smithsonian Castle in Washington, DC. They are significantly enriched in Mn compared to the underlying sandstone, by a factor of 100, which suggests that
Katherine E. Sharpless, Jeanice M. Brown Thomas, David L. Duewer
Since 1984, the National Institute of Standards and Technology (NIST) has coordinated what is now known as the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat-soluble vitamins and carotenoids in human serum
Cedric J. Powell, B Da, Shigeo Tanuma, H. Yoshikawa, H Shinotsuka, David R. Penn
We calculated electron inelastic mean free paths (IMFPs) for liquid water from its optical energy-loss function (ELF) for electron energies from 50 eV to 30 keV with the relativistic full Penn algorithm (FPA) that has been used for previous IMFP and
Broadband coherent anti-Stokes Raman scattering (BCARS) microspectroscopy is a unique label-free imaging modality that provides detailed chemical information at each pixel. In minutes, this technique captures a hyperspectral cube that co-registers
Monique E. Johnson, Antonio R. Montoro Bustos, Michael R. Winchester
The suitability of rate zonal density sucrose gradient centrifugation separation is explored for the purification/separation of three gold nanoparticles (AuNPs) mixtures (Mixture 1: 30 nm, 60 nm, and 100 nm; Mixture 2: 20 nm, 50 nm, and 100 nm; Mixture 3
Danyal J. Turkoglu, Robert G. Downing, Wangchun Chen, Dagistan Sahin, Jeremy C. Cook
Prompt gamma-ray activation analysis facilities with high neutron currents (≥109 s-1) generate triton-induced fast neutrons from 6Li-loaded collimators and beam stops at rates that soon damage gamma-ray detectors. We develop an alternative beam stop design
The eye-safe transmitter of a ground-based, integrated path differential absorption (IPDA) LIDAR (light detection and ranging) system is described and specified in detail. The transmitter is based on an actively stabilized, continuous-wave, single
The annellation theory method has been used to predict the locations of maximum absorbance (LMA) of the ultravioletvisible (UV-Vis) spectral bands in the group of polycyclic aromatic hydrocarbons (PAHs) C24H14 (dibenzo and naphtho)derivatives of
Size-exclusion chromatography (SEC) has benefitted from commercially-available on-line viscometers for thirty years now. Initial (and continued) interest was mostly in applying the universal calibration concept to obtain molar mass averages and
Vladimir L. Orkin, James B. Burkholder, S. P. Sander, J. P. D. Abbatt D. Abbatt, J. R. Barker, Robert E. Huie, C E. Kolb, Michael J. Kurylo III, David M. Wilmouth, P. H. Wine
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
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
To help optimize ion mobility spectrometry (IMS) for the detection of inorganic explosives, time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used to study the thermal desorption behavior of ammonium nitrate (NH4NO3) and potassium perchlorate
Sergey P. Belov, Alexandr V. Lapinov, Arthur A. Mescheryakov, Jon T. Hougen, Li-Hong Xu
This paper presents an explanation based on torsionally mediated proton-spinoverall-rotation interaction for the observation of doublet hyperfine splittings in some Lamb-dip sub-millimeter-wave transitions between ground-state torsion-rotation states of E