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Au/molecule/Ag junctions are shown to behave as voltage-controlled two-state switches. In the open state, the current-voltage behavior is consistent with a
Thermal-optical analysis (TOA) is a principal method for measuring elemental carbon (EC) associated with atmospheric soot. It relies on changes in the optical
John Butler, Eric Buel, Federica Crivellente, B R. McCord
DNA typing with short tandem repeat (STR) markers is now widely used for a variety of applications including human identification. Capillary electrophoresis (CE
An equation of state has been developed to model the phase equilibria of mixtures of water + organic solvents + salts. This modeis based on the Peng-Robinson
We report electron effective attenuation lengths (EALs) for SiO2 films on Si that were obtained from Monte Carlo simulations of substrate Si 2p3/2 photoelectron
A P. Miiller, M Bergoglio, N Bignell, Kitty Fen, S S. Hong, Karl Jousten, Pardeep Mohan, R J. Redgrave, M Sardi, D Simpson
This report decribes a CCM key comparison of low absolute-pressure standards at seven National Measurement Institutes (NMIs) that was carried out during the
A Teplyakov, G Obmolova, A Howard, Andrey Galkin, W Krajewski, E Sarikaya, O Herzberg, G L. Gilliland
With large-scale genomic sequencing efforts meeting with success, post-genomics research efforts are focusing on functional assignment of gene products. One
The speed of sound was measured in gaseous nitrous oxide (N2O) and nitric oxide (NO) using an acoustic resonance technique with a relative standard uncertainty
Observations of non-linear transport characteristics in nanoscale junctions triggered interest in phenylene ethynylene oligomers as potential electronic
Using site-directed mutagenesis we altered surface residues on Putidaredoxin to investigate which side-chain residues might be involved in the binding of
A device has been developed for introducing small quantities of gas directly to the specimen in the environmental scanning electron microscope chamber. This
Thermostable anthranilate synthase from the marine sulfate-reducing hyperthermophile Archaeoglobus fulgidus has been expressed in Escherichia coli, purified
A linear solvation energy relationship (LSER) has been developed to predict the water-R134a partition coeffiecients for a published collection of organic
Hydrated metal ions are important in a variety of biological and environmental systems, yet a comprehensive picture of the dynamic local environment associated
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