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Thermodynamics defines entropy only at equilibrium and says that, for an isolated system that undergoes an irreversible process, the entropy is increased. It is
The vapor-liquid equilibrium of the mixture composed of difluoromethane (R-32) and propane (R-290) was studied in the temperature range between 273.15 K and 313
Two recent developments in x-ray measurement technology provide dramatic improvements in analytical x-ray measurement science that will impact the frontiers of
Thermodynamic properties of several arsenic-containing substances are reviewed here, and a consistent set of thermodynamic properties for these species, derived
George A. Klouda, J Greg Gillen, Robert A. Fletcher, E S. Etz, Jennifer R. Verkouteren, R. Michael Verkouteren, E Ferguson
We are working in collaboration with the Transportation Security Agency's Trace Explosive Detection Group to build a chemical metrology program to help support
The experimental work of Ulrich Franck and his collaborators on phase separation in binary aqueous mixtures of gases at high pressures and temperatures is
The low penetration depth and high sputter rates obtained using polyatomic primary ions have facilitated their use for the molecular depth profiling of some
Energy dispersive x-ray spectrometry (EDS) is a spectral measurement tool used with a wide variety of excitation sources: electrons, ions and x-ray. Photon
The binding energies of the quaternary ions (CH 3)4N + and acetylcholine (ACh) to neutral molecules have been measured by pulsed high-pressure mass spectrometry
Terrence J. Jach, A S. Bakulin, S M. Durbin, J Pedulla, A T. Macrander
Hard x-ray imaging microscopy using multilayer-coated Kirkpatrick-Baez mirrors produces absorption images with one micron resolution or better when used with a
Rhodopsin is a retinal photoreceptor protein of bipartite structure consisting of the transmembrane protein opsin and the light Sensitive chromophore 11-cis
Rough samples with topography on a scale that is much greater than the micrometer dimensions of the electron interaction volume present an extreme challenge to
Yan Xiao, G Gannot, M Emmert-Buck, S Srivastava, Paul D. Wagner, Peter E. Barker
To improve quantitation of HER2 and telomerase as cancer biomarkers, we have generated novel avian polyclonal antibodies of IgY isotype for comparison with
The speed of sound was measured in gaseous nitrogen trifluoride, ethylene oxide, and trimethyl gallium using a highly precise acoustic resonance technique. The
This key comparison was intended to compare the capabilities for the preparation and value assignment of gas standards for hydrogen sulfide in nitrogen
Lam H. Yu, Christopher D. Zangmeister, James G. Kushmerick
We report the fabrication and characterization of multilayer thin films incorporating 1,8-octanedithiols and Ni atoms. Low-temperature charge transport
M C. Chakrabarti, J A. Carrasquillo, D Drumm, R D. Neumann, I Panyutin
We investigated the selective transfer of a plasmid to the target cells using an internalizing monoclonal antibody. We used T101 (IgG2a), a murinemonoclonal
A Lewandowska, F Tsvetkov, Howard J. Hanley, Thomas J. Bruno
Heats of adsoption for a series of hydocarbons on Laponite-RD clay were determined by two gas chromatographic methods. The first method was an extension of
With the increase in mass-spectrometry-based proteomics, many research projects depend on the chemistry of peptide fragmentation. Elucidating fragmentation
A new method is demonstrated which can be used to produce streams of variable, controlled analyte concentration. The method works by electrokinetically
The input to the elegant and simple algorithm by Melkman must not be three collinear points. Otherwise, the algorithm correctly removes collinear points.
The control region of mitochondrial DNA (mtDNA), commonly referred to as the D-loop, is highly polymorphic and contains a number of possible single nucleotide
Polyatomic primary ions have been recently applied to the depth profiling of organic materials by secondary ion mass spectrometry (SIMS). Polyatomic primary
X-ray diffraction patterns of tetragonal and cubic yttria-stabilized were simulated to test the capability of Rietveld refinement to accurately seperate the
Christopher G. Soares, S Vynckier, H Jarvinen, W G. Cross, J Hokkanen, P Sipila, D Fluhs, B Schaeken, F A. Mourtada, G A. Bass, T T. Williams
An international intercomparison of the dosimetry of three beta particle emitting ophthalmic applicators was performed, which involved measurements with
Inertial and resistive end corrections for the Greenspan acoustic viscometer were computed. The numerical results apply to a circular duct coupling two
Cedric J. Powell, Aleksander Jablonski, Francesc Salvat, S Tanuma, David R. Penn
A brief description is given of three recent developments concerning the generation and application of data for elastic and inelastic scattering of electrons
Cynthia S. Lo, Kunaljeet Tanwar, Anne M. Chaka, Thomas P. Trainor
The structures of the clean and hydrated hematite alpha-Fe2O3 (1-102) surfaces were investigated using density functional theory, and the free energies of the
The fibrillar growth habit and 100} twinning may produce anomalous optical properties in fibrous amphiboles. The optical properties of 16 fibrous tremolite
New U.S. Federal low-level automobile emission requirements, such as Zero Level Emission Vehicle (ZLEV), for hydrocarbons and other species have resulted in the