U.S. flag

An official website of the United States government

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.

Search Publications

NIST Authors in Bold

Displaying 851 - 875 of 3757

Dehydration vs. Deamination of N-Terminal Glutamine in Collision-Induced Dissociation of Protonated Peptide Ions

August 11, 2006
Author(s)
Pedatsur Neta, Quan-Long Pu, Lisa E. Kilpatrick, Xiaoyu Yang, Stephen E. Stein
… mass spectrometry in singly- and doubly-protonated peptide ions undergoing collision-induced dissociation in a triple … QLLLPLLLK and QLLLPLLLR show that the singly protonated ions undergo loss of ammonia and to a smaller extent loss of water, whereas the doubly protonated ions undergo predominantly loss of water. The fast …

Secondary Ion Yield Matrix Effects in SIMS Depth Profiles of Si/Ge Multilayers

April 1, 1989
Author(s)
John G. Gillen, J M. Phelps, Randall W. Nelson, Peter Williams, Steven M. Hues
… thicknesses of 4-33 nm, have been analyzed by secondary ion mass spectrometry (SIMS) using Ar+, O2+ and Cs+ primary ion beams. Bombardment with both Ar+ and O2+ produced positive secondary ion depth profiles in which pronounced distortions were … Secondary Ion Yield Matrix Effects in SIMS Depth Profiles of Si/Ge …

Density Functional Theory Meta-GGA+U Study of Water Incorporation in the Metal Organic Framework Material Cu-BTC

July 14, 2015
Author(s)
Eric J. Cockayne, Eric B. Nelson
… material Cu-BTC, up to a concentration of 3.5 H2O per Cu ion, is studied via density functional theory at the … The stable arrangements of water molecules show chains of hydrogen-bonded water molecules and a tendency to form closed … As expected, Cu-water oxygen interactions and water-water hydrogen bonding dominate the energetics. Stability is …

Phase-coherent sensing of the center-of-mass motion of trapped-ion crystals

November 9, 2020
Author(s)
Matthew Affolter, Kevin Gilmore, Elena Jordan, John Bollinger
… Measurements of the center-of-mass motion of a trapped-ion crystal that are phase- coherent with an external force … the trap motional frequency on a two-dimensional trapped ion crystal of approximately 100 ions, and determine the … of weak force and electric field detection below 10−3yN/ion and 1 nV/m, respectively. …

Spectroscopy of a single Al + ion via coupling to Be +

July 25, 2005
Author(s)
Till P. Rosenband, Piet Schmidt, Jeroen Koelemeij, Wayne M. Itano, Yohei Kobayashi, Tara M. Fortier, Scott A. Diddams, James C. Bergquist, David J. Wineland
… precision spectroscopy on 27 Al + with the aid of a 9 Be + ion. Using sympathetic cooling and quantum state transfer, we … Spectroscopy of a single Al + ion via coupling to Be + …

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

January 1, 2000
Author(s)
Joseph M. Antonucci, Drago Skrtic, E D. Eanes
… Bis-GMA/TEGDMA composites gave extremely low levels of ion release, the UDMA composites gave moderate sustainable release of ions. High, sustainable levels of ion release were obtained from the HEMA-containing … acid matrix composite based on PMGDMA initially gave high ion release, but this was not sustainable because of …

Exponentially correlated Hylleraas-Configuration Interaction studies of atomic systems. II. Non-relativistic energies of the 1 singlet S through 6 singlet S states of the Li+ ion

October 15, 2021
Author(s)
Maria B. Ruiz, James S. Sims, Bholanath Padhy
… examine not only the ground 1 singlet S state of the Li+ ion, but the 2 singlet S through 6 singlet S excited states … Lithium ion, non-relativistic energy, singlet S states, Hy-CI, E-Hy-CI … of the 1 singlet S through 6 singlet S states of the Li+ ion …

Importance of Excluded Volume on the Solvation of Urea in Water

May 1, 2004
Author(s)
Raymond D. Mountain, D Thirumalai
… solvation of urea depends not only on its ability to form hydrogen bonds with water but also its excluded volume. More … urea, is determined by the ability of the cosolute to form hydrogen bonds with the polypeptide chain which in turn … electrostatic interaction, excluded volume, hydrogen bond, molecular dynamics, solvation, urea …

Degradation of Poly (Acrylates Under SF 5 + Primary Ion Bombardment Studied Using Time of Flight Secondary Ion Mass Spectrometry 1. Effect of Main Chain and Pendant Methyl Groups

October 16, 2008
Author(s)
M S. Wagner
… to the depth profiling of organic materials by secondary ion mass spectrometry (SIMS). Polyatomic primary ions offer … of the polymer on its degradation under polyatomic primary ion bombardment has not yet been systematically studied. In this study, positive and negative ion time-of-flight SIMS (ToF-SIMS) was used to measure the …

Minimization of ion micromotion in a Paul trap

January 1, 1998
Author(s)
D J. Berkeland, J D. Miller, James C. Bergquist, Wayne M. Itano, David J. Wineland
… micromotion. The first relies on the change of the average ion position as the trap potentials are changed. The second … Minimization of ion micromotion in a Paul trap …

Experimental demonstration of robust, high-fidelity geometric two ion-qubit phase gate

January 1, 2003
Author(s)
Dietrich G. Leibfried, B. L. DeMarco, V Meyer, D Lucas, Murray D. Barrett, Joseph W. Britton, Wayne M. Itano, Branislav M. Jelenkovic, Christopher Langer, Till P. Rosenband, David J. Wineland
… a universal geometric pi-phase gate between two beryllium ion-qubits, based on coherent displacements induced by an … force can be considered constant over the extent of each ion's wave packet. By combining the gate with single-qubit … experiment demonstrating a universal gate between two ion-qubits. The particular properties of the gate make it …

Effect of Tin Doping on alpha-Fe2O3 Photoanodes for Water Splitting

June 28, 2012
Author(s)
Christopher C. Bohn, Amit Agrawal, Erich C. Walter, Mark D. Vaudin, Andrew Herzing, Paul M. Haney, Albert A. Talin, Veronika Szalai
… as high as 0.8 mA/cm2 at 1.23 V vs. the reversible hydrogen electrode (RHE). The incorporation of Sn into the … oxide (FTO) interface and was quantified using secondary ion mass spectrometry (SIMS) to give a mole fraction of … electrochemical impedance spectroscopy, dynamic secondary ion mass spectrometry …

Tests of Fundamental Physics

July 3, 2023
Author(s)
Eite Tiesinga, Peter Mohr
… tests rely on a combination of the spectroscopy of atomic hydrogen, $g$-factor measurements of a free electron as well as that of an electron bound in a hydrogen-like ion, and finally the mass determination of the ions through …

Chemical and Physical Changes During Seawater Flow through Intact Dunite Cores: An Experimental study at 150-200 degC

October 1, 2017
Author(s)
Andrew J. Luhmann, Benjamin M. Tutolo, Brian C. Bagley, David F. Mildner, Peter P. Scheuermann, Joshua M. Feinberg, Konstantin Ignatyev, Jr. Seyfried
… experiments at 150 and 200 °C, respectively. Furthermore, hydrogen and methane concentrations exceeded 600 υmol/kg and … little to no magnetite production, suggesting that the hydrogen was largely generated by the oxidation of iron as … this experiment generated significant dissolved hydrogen concentrations, while simulating open system …

Quantum Computing with Very Noisy Devices

February 13, 2007
Author(s)
Emanuel H. Knill
… This lecture was presented at the Workshop on Trapped Ion Quantum Computing hosted by NIST, February 21 - 24, 2006. … Workshop on Trapped Ion Quantum Computing hosted by NIST …

Degradation of Poly(Acrylates) Under SF 5 ^+^ Primary Ion Bombardment Studied Using Time of Flight Secondary Ion Mass Spectrometry3. Poly (Hydroxyethyl Methacrylate) With Chemical Derivazation

October 16, 2008
Author(s)
M S. Wagner
… Molecular depth profiling of polymers by secondary ion mass spectrometry (SIMS) has focused on the use of … chemistry on polymer degradation under polyatomic primary ion bombardment. In this study, time-of-flight SIMS … group chemistry on their degradation. The sputter rate and ion-induced damage accumulation rate of PHEMA were similar to …
Displaying 851 - 875 of 3757
Was this page helpful?