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Displaying 676 - 700 of 3086

Frequency Measurements of Al+ and Hg+ Optical Standards

June 8, 2009
Author(s)
Wayne M. Itano, James C. Bergquist, Till P. Rosenband, David J. Wineland, David Hume, Chin-wen Chou, Steven R. Jefferts, Thomas P. Heavner, Tom Parker, Scott Diddams, Tara Fortier
… aluminum ion, mercury ion, optical frequency standards, time variation of fundamental constants, trapped ion frequency standards …

Temperature-Controlled Depth Profiling in Polymeric Biomaterials Using Cluster Secondary Ion Mass Spectrometry

July 1, 2006
Author(s)
Christine M. Mahoney, Albert J. Fahey, John G. Gillen, Chang Xu, J Batteas
… Secondary Ion Mass Spectrometry (SIMS) employing an SF5+ polyatomic primary ion source was used to depth profile through various … rates, damage cross sections, and overall secondary ion stability) were monitored as a function of temperature. … in Polymeric Biomaterials Using Cluster Secondary Ion Mass Spectrometry …

Ab Initio Study of the Reactions Between a Series of Substituted Singlet Nitrenium Ions and Water

October 12, 2021
Author(s)
A A. Restrepo-Cossio, M Marquez, F Mari, Carlos A. Gonzalez
… the reactions of a series of substituted singlet nitrenium ions ( 1 [R-N-H] + , R=H, Cl, F, CN and Me) and water in gas … It was found that in gas phase and solution the nitrenium ions react in a barrierless fashion to produce an ylide-like … Between a Series of Substituted Singlet Nitrenium Ions and Water …

An 27 Al+ quantum-logic clock with systematic uncertainty below 10 -18

July 15, 2019
Author(s)
Samuel M. Brewer, Jwo-Sy Chen, Aaron M. Hankin, Ethan Clements, Chin-wen Chou, David J. Wineland, David Hume, David Leibrandt
… a frequency stability of 1.2 X 10 -15 /(T 1/2 ). A 25 Mg + ion is simultaneously trapped with the 27 Al + ion and used for sympathetic cooling and state readout during … to previous 27Al+ clocks, enabling clock operation with ion motion near the three-dimensional ground state. Operating …

Quantum interface between an electrical circuit and a single atom

March 30, 2012
Author(s)
Jacob M. Taylor, Dvir Kafri, David Kielpinski, G J. Milburn, M J. Woolley
… devices using the coupling between the motion of a single ion and the quantised electric field of the circuit. … coupling between the internal states of a single atomic ion and the electrical excitations of a superconducting … Ion traps, superconducting resonator, bulk acoustic waves …

Identifying capacitive and inductive loss in lumped element superconducting hybrid titanium nitride/aluminum resonators

June 9, 2012
Author(s)
Martin P. Weides, Jeffrey S. Kline, Martin O. Sandberg, David P. Pappas
… By measuring the power dependent loss at 50 mK as the Al/TiN fraction in each element is increased, we find that at … amount of Al in the inductance, with a power independent TiN-Al interface loss term that exponentially decreases as the temperature is reduced. The TiN-Al interface loss is vanishingly small at the 50 mK base …

Solution Structures of Bacillus Anthracis Protective Antigen Proteins using Small Angle Neutron Scattering and Protective Antigen 63 Ion Channel Formation Kinetics

December 11, 2021
Author(s)
Ariel Michelman-Ribeiro, Kenneth A. Rubinson, Vitalii Silin, John J. Kasianowicz
… are studying the structures of bacterial toxins that form ion channels and catalyze macromolecule transport across … alpha-hemolysin, anthrax, Bacillus anthracis, β-barrel, ion channel, pore forming toxin, PA63, PA83 … Small Angle Neutron Scattering and Protective Antigen 63 Ion Channel Formation Kinetics …

Electrospray Tandem Quadrupole Fragmentation of Quinolone Drugs and Related Ions. On the Reversibility of Water Loss from Protonated Molecules

November 30, 2010
Author(s)
Pedatsur Neta, Bhaskar Godugu, Yuxue Liang, Yamil Simon, Xiaoyu Yang, Stephen E. Stein
… The authors suggested formation of two singly protonated ions with different behavior, one undergoing loss of H 2 O … cone voltage as well. We further find that many fragment ions formed by loss of H 2 O can attach a water molecule in the collision cell, whereas ions formed by loss of CO 2 do not. Since re-attachment of H …

Fundamental constants and tests of theory in Rydberg states of one-electron ions

March 19, 2010
Author(s)
Ulrich D. Jentschura, Peter Mohr, Joseph N. Tan
… of the theory of circular Rydberg states of hydrogenlike ions allows highly-accurate predictions to be made for energy … can be increased by utilizing a variety of combinations of ions and Ryberg states to determine fundamental constants and … and tests of theory in Rydberg states of one-electron ions …

Filtering noise with a quantum probe

May 5, 2011
Author(s)
John J. Bollinger
… in general terms the ideas behind the manuscript "Single-ion quantum lock-in amplifier" by Kotler and colleagues which … of the valence electron spin of a single trapped strontium ion. … dynamical decoupling, ion trap, lock-in detection, quantum metrology, quantum …

Entropic modulation of divalent cation transport

September 22, 2025
Author(s)
Yechan Noh, Demian Riccardi, Alexander Smolyanitsky
… enthalpic contributions from transiently decreased ion-solvent and increased ion-pore electrostatic interactions. This commonly accepted … ion transport, thermodynamics, entropy, enthalpy, theory, …

Characterization of Drug-Eluting Stent (DES) Materials With Cluster Secondary Ion Mass Spectrometry (SIMS)

July 1, 2006
Author(s)
Christine M. Mahoney, Martin McDermott
… Secondary Ion Mass Spectrometry (SIMS) employing an SF5+ polyatomic primary ion source was utilized to analyze several materials commonly … molecular signal as a function of increasing SF5+ primary ion dose when experiments were performed at cryogenic … Drug-Eluting Stent (DES) Materials With Cluster Secondary Ion Mass Spectrometry (SIMS) …

Visible, EUV, and X-Ray Spectroscopy at the NIST EBIT Facility

April 24, 2004
Author(s)
John D. Gillaspy, B Blagojevic, Paul A. Dalgarno, K Fahey, V Kharchenko, J M. Laming, L Logosi, E-O Le Bigot, K Makonyi, L P. Ratliff, E Silver, H. Schnopper, E Takacs, J N. Tan, H Tawara, K Tokesi
… astrophysics, charge exchange, electron beam ion trap, EUV lithography, exreme ultraviolet, fusion, highly …

Effect of Resin Composition on the Remineralizing Ability of Amorphous Calcium Phosphate-Based Polymeric Composites

May 15, 2000
Author(s)
Drago Skrtic, Joseph M. Antonucci, E D. Eanes
… as the Gibbs free energy, DGo. Elevated Ca2+ and PO4 ion concentrations were sustained in all BTHZ and UH resins. … potential due to the resin retention of released Ca2+ via ion binding by carboxylic acid groups of PMGDMA. … Hybridization of the fillers had no effect on the ion release from BTHZ composites. However, internal …

Charge-exchange processes in EBIT: implications for spectral analysis of few-electron Fe ions

April 16, 2025
Author(s)
Yang Yang, FNU Dipti, Amy Gall, Nancy Brickhouse, Hunter Staiger, Galen O'Neil, Paul Szypryt, Adam Foster, David Schultz, Aung Naing, Joseph Tan, Daniel Swetz, Michael Fogle, Randall Smith, Yuri Ralchenko, Endre Takacs
… present measured and simulated spectra of few-electron Fe ions, where we used a single charge-exchange factor to reduce … implications for spectral analysis of few-electron Fe ions …

Effect of Cluster Ion Analysis Fluence on Interface Quality in SIMS Molecular Depth Profiling

November 10, 2009
Author(s)
Christopher Szakal, Steven Hues, J Greg Gillen, Joe Bennett
… Cluster ion beams are being routinely utilized in secondary ion mass spectrometry (SIMS) for molecular depth profiling … as soft organic matrices, often require large analysis ion fluences in order to generate sufficient count rates for … Effect of Cluster Ion Analysis Fluence on Interface Quality in SIMS Molecular …

Cation Diffusion at the Polymer Coating/Metal Interface.

January 1, 1995
Author(s)
Tinh Nguyen, Z Zhang, C Lin, J M. Pommersheim
Theoretical and experimental studies were carried out on the transport of cations in the channel between a polymer coating and a metal substrate from a defect in the absence of an applied electrical potential. The model consists of two stages: an initial

Observation of the 1 S 0 - 3 P 0 clock transition in 27 Al +

June 1, 2007
Author(s)
Till P. Rosenband, P. O. Schmidt, David Hume, Wayne M. Itano, Tara M. Fortier, Jason Stalnaker, Scott A. Diddams, Jeroen Koelemeij, James C. Bergquist, David J. Wineland
… 0 – 3 P 0 clock transition in 27 Al + . A single aluminum ion and a single beryllium ion are simultaneously confined in a linear Paul trap, … Coulomb repulsion. This coupling allows the beryllium ion to sympathetically cool the aluminum ion, and also …
Displaying 676 - 700 of 3086
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