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Radiochemical neutron activation analysis (RNAA) with retention on hydrate manganese dioxide (HMD) has played a key role in the certification of As in biological materials. A new RNAA procedure solvent extraction of As into zinc diethyldiothiocarbamate
A common issue, encountered in nanoparticle-biological system interaction studies is accurate nanoparticle concentration expression, given the critical importance of the dose-response relationships. We present here the application of quartz crystal
Benjamin Jacobs, Houk Ronald, Stephen House, Ian Robertson, Albert A. Talin, Mark Allendorf, Mitchell Anstey
Synthesis of metal nanoparticles and nanowires with controlled size and aspect ratio is well developed,1-4 but the creation of ordered nanostructures comprising these is much more challenging, presenting a barrier to further development of electronic and
Yamil Simon, Carlos A. Gonzalez, Patricio Fuentealba
Experimental and theoretical studies of atomic clusters have proven to be a challenging research theme, but also one of great practical importance in developing new technologies [1 and references therein]. The physical and chemical properties of atomic
The connection between hydrogen bonding between water and acetonitrile in determining the microheterogeneity of the liquid mixture is examined using NPT molecular dynamics simulations. Mixtures for six, rigid, three-site models for acetonitrile and one
When withdrawing a fluid sample from an apparatus at reduced pressures for additional chromatographic analyses, a gas tight plunger syringe proves ineffective as it does not create a substantial pressure differential to pull a fluid from a reduced pressure
Jayne B. Morrow, Catalina Arango, Richard D. Holbrook
Quantum dots (QDs) of two different surface chemistries (carboxyl (COOH) and poly ethylene glycol (PEG) modified) were utilized to determine the impact of surface functionality on QD mobility and distribution in Pseudomonas aeruginosa PAO1 biofilms
James E. Noble, David M. Bunk, R. H. Christenson, Kenneth D. Cole, Hua-Jun He, Alexei Katrukha, Mauro Panteghini, Robert Porter, Heinz Schimmel, Jillian Tate, Lili Wang
The development of a reference measurement procedure to support the cardiac troponin I (cTnI) standardization initiative is described. The reference measurement procedure will be used to assign reference values to serum-based secondary standards. A
Tara Lovestead, Bret Windom, Jennifer Riggs, Chris Nickell, Thomas J. Bruno
RP-1 is a long-established hydrocarbon fuel that continues to be widely used as the kerosene component in rocket propulsion systems. The desire in recent years to use rocket motors many times, rather than a single time, has led to reformulations of RP-1
Dean C. Ripple, Richard Davis, Bernd Fellmuth, Joachim Fischer, Graham Machin, Terry Quinn, Peter Steur, Osamu Tamura, David R. White
The mise en pratique (practical realization) for the definition of the kelvin (MeP-K) was created by the Consultative Committee for Thermometry (CCT) in 2006 to give practitioners of thermometry a guide to the realization of the kelvin, in accord with
The bilateral comparison between NIM and NIST for gas flow was conducted from June 2008 to October 2009. Two critical flow venturis (CFVs) with nominal throat diameters of 10 mm and 20 mm, respectively, were selected as transfer standards. The CFVs were
Accurate gas properties are needed to take full advantage of the low uncertainties provided by NISTs Gas Flow Calibration Services. If a flowmeter user and NIST use different values for these properties (molecular mass, compressibility, density, viscosity
Danielle Cleveland, Stephen E. Long, Lane C. Sander, William C. Davis, Karen E. Murphy, Catherine A. Rimmer, Lorena Francini, Anil K. Patri
Speciation measurements of gadolinium in liposomal MRI contrast agents are complicated by the presence of emulsifiers, surfactants, and therapeutic agents in the formulations. The present paper describes two robust, hyphenated chromatography methods for
We analyze here the spectrum of the AI Kα and Mg Kα x-ray lines obtained by electron excitation of a multielement glass. The spectrum was obtained in an electron beam probe using a microcalorimeter x-ray detector. With 7 eV resolution, we are able to
Chris D. Muzny, Sergey P. Verevkin, Vladimir N. Emel'yanenko, Dzmitry H. Zaitsau, Andreas Heintz, Michael D. Frenkel
In this work the molar enthalpy of formation of the ionic liquid ethyl-methylimidazolium dicyanoamide in the gaseous phase [C2MIM][N(CN)2] was measured by means of combustion calorimetry and enthalpy of vaporization using transpiration. Available scarce
Both organic and inorganic chemistry have benefited greatly from the availability of tables of standard enthalpies of formation fH, standard Gibbs energies of formation fG, and standard entropies S. These tables of standard thermodynamic properties
Stephanie L. Outcalt, Arno R. Laesecke, Karin Brumback
The density of a flightline jet fuel (JP-8) was measured with two vibrating-tube densimeters. The combined range of the data is from 270 K to 470 K with pressures to 40 MPa. The speed of sound in the fuel was measured with a propagation time method at
Problems associated with pre-ignition of fuel in a spark ignition engine have been documented for many years, and include poor performance and structural damage. These problems were addressed in the past by adding organometallic additives such as
BioPAX (Biological Pathway Exchange) is a standard language to represent biological pathways and processes at the molecular and cellular level. Its major use is to facilitate the exchange of pathway data (http://www.biopax.org). Pathway data captures our
Faced with limited evidence that yield low amounts of DNA, forensic analysts will continually have to confront the question of how far to push DNA testing techniques. Low copy number (LCN) analysis, also known as low template DNA (LT-DNA) testing, involves
Christine M. Mahoney, James G. Kushmerick, Kristen L. Steffens
Cluster Secondary Ion Mass Spectrometry (cluster SIMS) has been proven to be a useful technique for the surface and in-depth characterization of molecular films. Here, an SF5+ polyatomic primary ion source is utilized for depth profiling in poly(methyl
Christine M. Mahoney, Albert J. Fahey, Kristen L. Steffens, Richard T. Lareau
The application of surface analytical techniques such as Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS), and X-ray Photoelectron Spectroscopy (XPS) are explored as a means of differentiating between C-4 samples. Three different C-4 samples; U.S
Ian M. Anderson, Michael D. Anderson, Andrew A. Herzing, Colby Heideman, Raimar Rostek, David C. Johnson
An ultra-low thermal conductivity compound with the ideal formula [(PbSe)1.00]1[MoSe2]1 has been successfully crystallized across a range of compositions. The lattice parameters varied from 12.41 Å to 12.75 Å and the quality of the observed 00ℓ diffraction
Stephen T. Stern, Jennifer B. Hall, Lee L. Yu, Laura J. Wood, Giulio F. Paciotti, Lawrence Tamarkin, Stephen E. Long, Scott E. McNeil
There are many important considerations during preclinical development of cancer nanomedicines, including: 1) unique aspects of animal study design; 2) the difficulties in evaluating biological potency, especially for complex formulations; 3) the