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Displaying 151 - 175 of 3839

Ab initio kinetic coefficients of gaseous hydrogen

January 9, 2010
Author(s)
James B. Mehl, Marcia L. Huber, Allan H. Harvey
… The spherical portion of the hydrogen intermolecular potential recently determined in ab … and spherical contribution to the thermal conductivity of hydrogen using a full quantum-mechanical formalism. … difference between three experimental data sets for hydrogen spanning 21 314 K was (0.3 1.0)%; the average …

A compact, UHV ion source for enriching 28Si and depositing epitaxial thin films

August 22, 2019
Author(s)
Ke Tang, Hyun S. Kim, Aruna N. Ramanayaka, David S. Simons, Joshua M. Pomeroy
… An ultra-high-vacuum (UHV) compatible Penning ion source for growing pure, highly enriched 28Si epitaxial … discuss the discharge properties of this new source, the ion mass spectrum when coupled to our mass filter, and the secondary ion mass spectroscopy (SIMS) of the grown films. …

Optimization of the Pore Structures of MOFs for Record High Hydrogen Volumetric Working Capacity

April 28, 2020
Author(s)
Xin Zhang, Rui-Biao Lin, Jing Wang, Bin Wang, Bin Liang, Taner N. Yildirim, Jian Zhang, Wei Zhou, Banglin Chen
… frameworks are promising materials for onboard hydrogen storage thanks to the tunable pore size, pore … structures, the correlation between the pore volume and hydrogen storage capacity is examined and two empirical equations are rationalized to predict the hydrogen storage capacity of MOFs with different pore …

The Mobilities of NO + (CH 3 CN)n Cluster Ions (n=0-3) Drifting in helium-Acetonitrile Mixtures

December 1, 1996
Author(s)
J A. de Gouw, L N. Ding, M Krishnamurthy, H S. Lee, E B. Anthony, V M. Bierbaum, S R. Leone
… The mobilities of NO+(CH 3 CN) n cluster ions (N=0-3) drifting in helium and in mixtures of helium and … of the geometric cross sections of the different cluster ions. The rate constants for the various cluster formation … 2 and NO + (CH 3 CN) 3 , the drift velocities for these ions are found to be strongly dependent on the acetonitrile …

Hydrogen Field Test Standard: Laboratory and Field Performance

November 10, 2015
Author(s)
Jodie G. Pope, John D. Wright
… and measures inspectors to periodically test retail hydrogen dispensers, much as gasoline dispensers are tested … Flow Facility with helium gas and in the field at a hydrogen dispenser location. All three methods agree within … test drafts of helium gas in the laboratory setting and of hydrogen gas in the field, respectively. The time required to …

THE EFFECT OF MICROSTRUCTURE ON THE HYDROGEN-ASSISTED FATIGUE OF PIPELINE STEELS

July 14, 2013
Author(s)
Andrew J. Slifka, Elizabeth S. Drexler, Robert L. Amaro, Damian S. Lauria, April Stevenson, Douglas G. Stalheim, Louis E. Hayden
… fatigue tests were performed at 5.5 and 34 MPa pressurized hydrogen gas, at 1 Hz and (load ratio) R=0.5. At high pressures of hydrogen and high values of the stress intensity range (ΔK) … fatigue, hydrogen, hydrogen embrittlement, microstructure, pipeline steel, X52, …

Scanning Ion Microscopy with Low Energy Lithium Ions

July 1, 2014
Author(s)
Kevin A. Twedt, Lei Chen, Jabez J. McClelland
… Using an ion source based on photoionization of laser-cooled lithium atoms, we have developed a scanning ion microscope with probe sizes of a few tens of nanometers … in ion microscopy when detecting backscattered ions, due to a decreased interaction volume and the potential …

Outlook and Challenges for Hydrogen Storage in Nanoporous Materials

March 1, 2016
Author(s)
D. P. Broom, C. J. Webb, K. E. Hurst, P. A. Parilla, T. Gennett, Craig Brown, R. Zacharia, E. Tylianakis, E. Klontzas, G. E. Froudakis, Th. A. Steriotis, P. N. Trikalitis, D. L. Anton, B. Hardy, D. Tamburello, C. Corgnale, B. A. van Hassel, D. Cossement, R. Chahine, M. Hirscher
… been made recently in the use of Nanoporous materials for hydrogen storage. In this article, the current status of the … of the experimental investigation of real adsorptive hydrogen storage tanks, the improvement of the thermal … hydrogen storage, adsorption, isotherm, structure, …

Infrared emission imaging as a tool for characterization of hydrogen storage materials

December 6, 2008
Author(s)
H. Oguchi, Edwin J. Heilweil, Daniel Josell, Leonid A. Bendersky
… the in-situ hydrogenation of Mg_x}Ni_1-x} films with hydrogen gas; the method is shown to be a powerful … combinatorial screening tool for metal hydrides-base hydrogen storage materials. The 100 nm-thick Mg_x}Ni_1-x} … differences of the metallic and hydride phases. Hydrogen absorption and desorption of the films were …

Hydrogen Field Test Standard Design, Operating Instructions, & Specifications

September 10, 2015
Author(s)
Jodie G. Pope
… and measures inspectors to periodically test retail hydrogen gas dispensers, much as gasoline dispensers are … Flow Facility with helium gas and in the field at a hydrogen dispenser location. This document describes the … safety instrumentation for working with high pressure hydrogen gas, how to execute tests with the FTS, and the …

Hydrogen traps in the outgassing model of a stainless steel vacuum chamber

March 31, 2014
Author(s)
Robert F. Berg
… This article describes a model for hydrogen outgassing into a stainless steel vacuum chamber. It … accounts for the geometry of the chamber components, the hydrogen dissolved in those components, and the processes of … recombination, and trapping. Strongly bound or “trapped” hydrogen, which occurs at heterogeneities such as …

Metal-Assisted Hydrogen Storage on Pt-Decorated Single-Walled Carbon Nanohorns

June 23, 2012
Author(s)
Yun Liu, Craig M. Brown, Dan A. Neumann, David B. Geohegan, Alexander A. Puretzky, Christopher M. Rouleau, Hui Hu, David Styers-Barnett, Pavel O. Krasnov, Boris I. Yakobson
… Current methods to study the spillover effect in hydrogen storage materials typically must compare the results … to determine with confidence the amount of adsorbed hydrogen only associated with spillover. We propose two … pressure gas adsorption experiments to distinguish between hydrogen adsorbed due to physisorption and hydrogen adsorbed …

X-Ray Spectroscopy of Trapped Ions With a Microcalorimeter on the NIST Electron Beam Ion Trap

December 1, 2002
Author(s)
E Takacs, John D. Gillaspy, L P. Ratliff, K Makonyi, J M. Laming, E Silver, H. Schnopper, M Barbera, J. Beeman, E. E. Haller, N. Madden
… The electron beam ion trap (EBIT) was invented about 15 years ago. Judging from … and study the structure and interactions of highly charged ions. Today, EBITs exist in several different laboratories … in a variety of fields of research where multiply charged ions relevant. Recent astrophysical missions by NASA and …

Substrate Specificity of the Ogg1 Protein of Saccharomyces Cerevisiae: Excision of Guanine Lesions Produced in DNA by Ionizing Radiation- or Hydrogen Peroxide/Metal Ion-Generated Free Radicals

January 1, 1998
Author(s)
B. Karahalil, P M. Girard, S Boiteux, M. Dizdaroglu
… Guanine Lesions Produced in DNA by Ionizing Radiation- or Hydrogen Peroxide/Metal Ion-Generated Free Radicals … Guanine Lesions Produced in DNA by Ionizing Radiation- or Hydrogen Peroxide/Metal Ion-Generated Free Radicals …

Microstructure and hydrogen bonding in water-acetonitrile mixtures

November 19, 2010
Author(s)
Raymond D. Mountain
… The connection between hydrogen bonding between water and acetonitrile in … simulated to determine the amount of water-acetonitrile hydrogen bonding. None of the six mixtures were able to reproduce the expermental estimates of hydrogen bonding derived from Raman scattering of the CN …

Performance of a C 60 + Ion Source on a Dynamic SIMS Instrument

July 1, 2006
Author(s)
Albert J. Fahey, John G. Gillen, P Chi, Christine M. Mahoney
… An IonOptika [1] C60+ ion source has been fitted onto a CAMECA [1] ims-4f. Stable ion beams of C60+ and C602+ have been obtained with typical … able to be focussed into a spot size of ~1 ?m and scanning ion images acquired. We have performed analyses to … Buckministerfullerene, cluster ion beams, ion source, SIMS ion source …

International Comparison CCQM-K41: Hydrogen Sulfide in Nitrogen

October 16, 2008
Author(s)
Franklin R. Guenther, Walter R. Miller Jr.
… the preparation and value assignment of gas standards for hydrogen sulfide in nitrogen, maintained at the participating … the cylinders could not be prepared gravimetrically as hydrogen sulfide may be absorbed onto the walls of the … laboratory also analyzed a stable reference, a hydrogen sulfide gas mixture that had been shown to be stable …

Noninvasive monitoring of ion current and ion energy during plasma processing

July 15, 2008
Author(s)
Mark A. Sobolewski
… technique has been developed for noninvasive monitoring of ion energy and ion current in plasma reactors. The technique relies on … electrical waveforms, the technique determines the total ion current, the plasma potential and sheath voltage … ion current, ion energy, electrical measurements, inductively …

Cold atomic beam ion source for focused ion beam applications

July 23, 2013
Author(s)
Brenton J. Knuffman, Adam V. Steele, Jabez J. McClelland
… We report measurements and modeling performed on an ion source based on ionization of a laser-cooled atomic beam. … for use in next-generation, high-resolution focused ion beam (FIB) systems. Our measurements of total ion current as a function of ionization conditions support a …

Inter-ion Coulomb interactions in a Magneto-Optical Trap Ion Source

May 19, 2011
Author(s)
Jabez J. McClelland, Brenton J. Knuffman, Adam V. Steele
… We have investigated the role played by inter-ion Coulomb interactions in a magneto-optical trap ion source (MOTIS). Using a Monte Carlo simulation accounting … MOTIS, ion beams, coulomb replusion … Inter-ion Coulomb interactions in a Magneto-Optical Trap Ion Source …

Chapter 13. Color Quality of White LEDs

May 24, 2013
Author(s)
Yoshihiro Ohno
This chapter overviews the fundamentals of chromaticity and color rendering as the two important aspects of color quality of light sources for general illumination, with special focus on the use for solid state light sources. The section for chromaticity
Displaying 151 - 175 of 3839
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