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Francis J. Lovas, David F. Plusquellic, Brooks Pate, Justin L. Neill, Matt T. Muckle, Anthony J. Remijan
The microwave spectrum of the sugar alcohol 1,2-propanediol (CH3CHOHCH2OH) has been measured over the frequency range 6.5 GHz to 25.0 GHz with several pulsed-beam Fourier-transform microwave spectrometers. Seven conformers of 1,2-propanediol have been
We examine the perturbations of the modes of an acoustic thermometer caused by circular ducts used either for gas flow or as acoustic waveguides coupled to remote transducers. We calculate the acoustic admittance of circular ducts using a model based on
James W. Schmidt, Michael R. Moldover, Eric F. May
We used a quasi-spherical cavity resonator to measure the relative dielectric permittivity ε r of H 2 at frequencies from 2.4 GHz to 7.3 GHz, at pressures up to 6.5 MPa, and at the temperatures 273 K and 293 K. The resonator was calibrated using auxiliary
F Case, Anne M. Chaka, J Moore, Raymond D. Mountain, J Olson, Richard B. Ross, Martin Schiller, Vincent K. Shen, Eric A. Stahlberg
The fifth industrial fluid properties simulation challenge was held in 2008. In it the contestants were challenged to predict specific, industrially relevant, properties of fluid systems, namely the 1-octanol /water partition coefficient and the infinite
1. Table 23-2-1-(9.32000)-d, Pages d-6376.0 through d-6376.1: New table for cyclic carbonates, C3 to C5, for the condensed phases at one bar, or at equilibrium vapor pressure above the boiling point. 2. Table 14-2-(1.01000)-db, Pages db-290.0 through db
The use of purge and trap methods for sampling volatile organic compounds prior to chromatographic analysis is a mature technology. Application to low volatility compounds has been far less facile and sensitive. Especially problematic has been applications
Standard materials certified using electrochemical techniques include many of the most-used certified reference materials (CRMs). These CRMs provide traceability for some of the most-frequently-performed chemical measurements, including pH, electrolytic
Robert G. Brinson, Kevin Turner, Hye Y. Yi-Brunozzi, Stuart F. Le Grice, Daniele Fabris, John P. Marino
During (-)-strand DNA synthesis in retroviruses and Saccharomyces cerevisiae LTR-retrotransposons, a purine rich region of the RNA template, known as the polypurine tract (PPT) is resistant to RNase H-mediated hydrolysis and subsequently serves as a primer
Azeotrope mixtures are among the most fascinating, and at the same time the most complicated manifestations of phase equilibrium. They are also a critical aspect of many industrial processes and products. Indeed, with the current interest in alcohol
Thomas J. Bruno, Arron Wolk, Alexander Naydich, Marcia L. Huber
We have recently introduced several important improvements in the measurement of distillation curves of complex fluids. The modifications to the classical measurement provide for (1) a composition explicit data channel for each distillate fraction (for
Gregory C. Turk, Heinrich Kipphardt, Ralf Matschat, Jochen Vogl, Tamara Gusarova, Michael Czerwensky, Hans-Joachim Heinrich, Akiharu Hioki, Leonid A. Konopelko, Brad Methven, Tsutomu Miura, Ole Petersen, Gundel Riebe, Ralph Sturgeon, Lee L. Yu
Within the National Metrology Institutes (NMIs) and designated laboratories, an interlaboratory comparison, CCQM-P107, was conducted to verify the degree of international comparability concerning the results of purity analysis. The mass fractions of Ag, Bi
Douglas C. Meier, Baranidharan Raman, Stephen Semancik
Complex analytical problems, such as detecting trace quantities of hazardous chemicals in ambient environments composed of varying levels of humidity and vapors of benign products, require solutions that most effectively extract the relevant information
Christopher D. Zangmeister, Savelas A. Rabb, Du Bingchen, YuYe Tong
Controlled Pt adlayers were deposited on commercial Ru nanoparticles (NPs) using an industrially scalable one-pot ethylene glycol (EG) reduction based method and were characterized by X-ray diffraction (XRD), electrochemical (EC) CO stripping voltammetry
JP-7 is a hydrocarbon-based kerosene fraction with a low volatility and high thermal stability. JP-7 was developed in the 1950s to meet the more stringent requirements necessary for the development of high-altitude reconnaissance planes that fly at speeds
Karen E. Murphy, Thomas W. Vetter, Gregory C. Turk, Christopher D. Palmer, Miles E. Lewis, Ciaran M. Geraghty, Patrick J. Parsons, William F. Guthrie
The National Institute of Standards and Technology (NIST) has developed Standard Reference Material (SRM) 955c, a new caprine-based, four-level blood standard with certified blood lead levels (BLLs) ranging from 0.4 µg/dL (0.02 µmol/L) Pb to 45 µg/dL (2.17
Since the days of the alchemist, the observation that some substances have a smell while others do not has been a source of fascination. The sense of smell, or olfaction, is our least developed and least understood sense, however it is important for many
We give a survey of information needed for quantitative surface analyses by X-ray photoelectron spectroscopy (XPS). We describe four terms (the inelastic mean free path, the effective attenuation length, the mean escape depth, and the information depth)
Ryan G. Brennan, Savelas A. Rabb, Marcia J. Holden, Michael R. Winchester
An automated sample introduction system, utilizing a demountable direct injection high efficiency nebulizer (d DIHEN), is successfully incorporated for the first time with an inductively coupled plasma optical emission spectrometer (ICP-OES) for the
Jeffrey A. Caufield, Thomas J. Bruno, Keith Miller
Worldwide terrorism has recently resulted in increased efforts to detect and identify explosive residues. Availability of experimentally determined thermochemical data for explosive compounds and their degradation products are limited, however. Gas
While the use of ethanol and ethanol blends as motor fuels dates back to the earliest vehicles, ethanol has recently received extraordinary attention as a renewable liquid fuel. In the United States, the application of this fluid is mainly as an additive
Classical methods for the study of complex fluid phase behavior include static and dynamic equilibrium cells that usually require vapor and liquid recirculation. These are sophisticated, costly apparatus that require highly trained operators, usually
Jason G. Kralj, Audrey Player, Hope Sedrick, Matt S. Munson, David Petersen, Samuel P. Forry, Paul Meltzer, Ernest Kawasaki, Laurie E. Locascio
We show single-cell level linear amplification of gene expression libraries immobilized on a microfluidic packed bed. This is a critical step in the Eberwine process, which is used to amplify messenger RNA (mRNA) for gene expression profiling. Microarray
Lorna T. Sniegoski, Jocelyn L. Prendergast, Michael J. Welch, Alim A. Fatah, M Gackstetter, R. Q. Thompson
Several point-of-collection (POC) devices for detection of drugs of abuse in oral fluid were studied. The ability of the devices to meet the manufacturers' claims and their practical application to detection of drugs of abuse at low concentrations in oral
Joseph M. Antonucci, Anthony A. Giuseppetti, Justin N. O'Donnell, Gary E. Schumacher, Drago Skrtic
Objective: To assess the effect of the cavity design factor (C-factor) on polymerization stress development (PSD) in resin composites. Methods: An experimental resin (BT resin) was prepared, which contained 2,2-bis[p-(2 hydroxy-3 -methacryloxypropoxy