An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
We present grand canonical transition-matrix Monte Carlo (GC-TMMC) as an efficient method for simulating gas adsorption processes, with particular emphasis on subcritical gas adsorption in which capillary phase transitions are present. As in other
Ruth L. Jacobsen, Karl K. Irikura, Russell D. Johnson III, Raghu N. Kacker
Anharmonic calculations using vibrational perturbation theory are known to provide near-spectroscopic accuracy when combined with high-level ab initio potential energy functions. However, performance with economical, popular electronic structure methods is
Christopher R. Anderton, Kiran Bhadriraju, Frank W. DelRio, Anne L. Plant
The extracellular matrix (ECM) environment plays a critical role in organism development and disease. Consequently, developing complementary analytical techniques to study bioactive scaffolds can assist in understanding cell-ECM processes. We have
One can take advantage of the striking similarity of ignitable liquid vaporization (or weathering) patterns and the separation observed during distillation to predict the composition of residual compounds in fire debris. This is done with the advanced
Shonali Nazare, Shaun M. Flynn, Rick D. Davis, Joannie W. Chin
In this study, environmentally stressed OS fabrics containing melamine fiber blends were evaluated for thermal and mechanical properties that are critical to the protective performance of firefighter turnout gear. Environmental stress factors that affect
Mark S. Lowenthal, Nirina Rabe Andriamaharavo, Stephen E. Stein, Karen W. Phinney
A gas chromatography-mass spectrometry-based (GC-MS) method was developed for qualitative characterization of metabolites found in Vaccinium-fruit (berry) dietary supplement Standard Reference Materials (SRMs). Definitive identifications are provided for
A pinhole orifice with a known conductance can be used as the basis of a flowmeter. Commercially available laser-drilled pinhole orifices with diameters ranging from 1.0 μm to 50 μm can have conductances ranging from about 0.1 μL/s to 200 μL/s in the
D Vega-Maza, W. Wyatt Miller, Dean C. Ripple, Gregory E. Scace
We have constructed a new humidity generator that produces gas streams of known moisture content at temperatures from 85 °C to 200 °C, absolute pressures from 0.2 MPa to 1.6 MPa, and relative humidities from 10 % to 90 %. The generator produces a moist gas
Walter J. Lafferty, Jean-Marie Flaud, A. Ben Hassen, F. K. Kwabia Tchana, X Landsheere, H Aroui
Fourteen Fourier transform spectra of ethylene (C2H4) have been recorded in the 1800-2350 spectral domain with different path-lengths and pressures and used to derive individual line intensities for lines belonging to the ν7 + ν8, ν4 + ν8 , ν6 + ν10, ν6 +
Electron magnetic resonance (EMR) spectroscopy was used to determine the magnetic properties of maghemite (gamma-F e2O 3) nanoparticles formed within size-constraining Listeria innocua Dps protein cages that have an inner diameter of 5 nm. Variable
Li Liu, Dan Bearden, Juan C. Rodriguez, Kathleen S. Rein
Pahayokolides A-B are cyanobacteria derived non-ribosomal peptides which exhibit cytotoxicity against a number of cancer cell lines. The biosynthetic origin of the 3-amino-2,5,7,8- tetrahydroxy-10-methylundecanoic acid (Athmu) moiety has been investigated
Lili Wang, Steven J. Choquette, Yu-Zhong Zhang, Victoria Karpiak, Adolfas Gaigalas
A commercial spectrometer with an integrating sphere (IS) detector was used to measure the scattering cross section of microspheres. Analysis of the measurement process showed that two measurements of the extinction, one with the cuvette placed in the
Donor-acceptor interfaces are critical for the operation of organic photovoltaic devices. Exciton dynamics, leading to charge separation and recombination at these interfaces, play a significant role in determining efficiency, potentially controlling open
Michal Fulem, Kvetoslav Ruzicka, Marisa A. Rocha, Luis M.N.B.F. Santos, Robert F. Berg
Recommended vapor pressure data for ferrocene (CAS Registry Number: 102-54-5) in the temperature range from 242 to 447 K were developed by the simultaneous correlation of critically assessed vapor pressures, heat capacities of the crystalline phase and the
A series of three Hydrogen in Titanium Alloy Standard Reference Materials (SRMs 2452, 2453, and 2454) were prepared with hydrogen mass fractions bracketing the hydrogen specification limit of 125 mg/kg. Commercial titanium alloy Ti6Al4V (6 % aluminum, 4 %
Shonali Nazare, Jeffrey W. Gilman, Mauro Zammarano, Luke Haverhals, W.Matthew Reichert, Hugh De Long, Paul C. Trulove
In addition to being efficient solvents for biopolymers, several ionic liquids (ILs) have been shown to be effective solvents for synthetic polymers such as meta-aramids, i.e., Nomex ® (1-5). In this report, meta-aramid/cotton composites are generated by
Stacy S. Schuur, Paul R. Becker, Sylvain Berail, Russell D. Day, Olivier F. Donard, Keith A. Hobson, Amanda J. Moors, Rebecca S. Pugh, Lauren B. Rust, David G. Roseneau
Since 1999, the Seabird Tissue Archival and Monitoring Project (STAMP) has collected, banked, and analyzed seabird eggs using established protocols to monitor chlorinated pesticides, polychlorinated biphenyls (PCBs), brominated flame retardants, and
Additive packages are used with aviation kerosenes to achieve performance enhancements such as higher or lower operating temperatures or increased lubricity. An additive used to increase operating temperatures for heat sink applications is the +100
Tighe Spurlin, John T. Elliott, Michael W. Halter, Kiran Bhadriraju, Alessandro Tona, Anne L. Plant, Annalaura Mancia, Bobby L. Middlebrooks, Gregory W. Warr
Descriptive terms are often used to characterize cells in culture, but the use of nonquantitative and poorly defined terms can lead to ambiguities when comparing data from different laboratories. Although recently there has been a good deal of interest in
Thomas J. Bruno, George G. Anitescu, Lawrence L. Tavlarides
To develop efficient reactor and plant designs to optimize the process of biofuel production, thermophysical and chemical properties of various reactive mixtures as well as those of biofuel are required over wide range of conditions. In this study, the
David A. Sheen, Claudette M. Rosado-Reyes, Wing Tsang
Unsaturated hydrocarbons are an important component of hydrocarbon fuels and intermediates in their oxidation. Under rich conditions, H atom attack is one of the principle pathways of the decomposition of these unsaturated compounds. Consequently, it is
Highly accurate spectroscopic models for O2 A-band absorption are required in numerous satellite- and ground-based remote sensing measurements of atmospheric greenhouse gases. In this study, we quantify the sensitivity of the calculated A-band transmission