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D. Veza, Craig J. Sansonetti, Marc L. Salit, John C. Travis
Wave numbers and pressure-induced shifts of 19 argon emission lines were measured with high accuracy using a UV/visible Fourier transform spectrometer (FTS). The measurements were made using electrodeless lamps containing traces of 198Hg and argon at
A users guide is presented for Standard Reference Material (SRM) 2569 Lead in Paint Films for Childrens Products. This SRM consists of paint films on coupons of polyester with the paint characterized for mass fraction of Pb, mass of Pb per unit area
Deuterium was discovered by atomic spectroscopy 80 years ago, and led to the rapid development of nuclear energy and isotope chemistry. Atomic spectroscopy of deuterium remains vibrant, with a recent application to understanding the early universe.
Jianyuan Zhang, Fuhrer Tim, Wujun Fu, Jiechao Ge, Dan Bearden, Jerry Dallas, Duchamp James, Kenneth Walker, Hunter Champion, Hugo Azurmendi, Kim Harich, Harry C. Dorn
The encapsulation of clusters (or small molecules) in spheroidal fullerene cages provides a unique isolated environment that is important in describing their shape, dynamics, and physical properties. For the case of yttrium carbide clusters, we find that
E. M. Vess, C. J. Wallace, H. M. Campbell, V. E. Awadalla, Joseph T. Hodges, David Long, D. K. Havey
We present laboratory measurements of H2O-broadened 16O2 A-band ( ) absorption spectra acquired with a laser-based photoacoustic spectroscopy method. This absorption band is widely used in a variety of high-precision atmospheric remote sensing applications
Naturally occurring hydrogenases catalyze the reaction of H+ to form H2 gas. To develop a hydrogen source that is not reliant on fossil fuels, synthetic [FeFe]-hydrogenase model species are being studied. These compounds have a wing-like structure with a
Matthew T. Hunley, Santanu S. Kundu, Peter M. Johnson, Kathryn Beers
Recent advances in enzyme, metal, and organic catalysts have enabled the development of advanced functional polymers from cyclic ester and cyclic carbonate monomers. In this work, we present an in situ technique to monitor ring-opening polymerization using
The application of metabolomics in the field of environmental science or ecology, which has developed based substantially on NMR spectroscopic approaches, is a fast paced, rapidly developing field which seems to be poised to help re-frame the discussion of
James E. Maslar, William A. Kimes, Brent A. Sperling
An in situ gas-phase diagnostic for the metal alkylamide compound tetrakis(ethylmethylamino) hafnium (TEMAH), Hf[N(C2H5)(CH3)]4, was demonstrated. This diagnostic is based on direct absorption measurement of TEMAH vapor using an external cavity quantum
Vladimir L. Orkin, Victor Khamaganov, Michael J. Kurylo III
Rate constants for the gas phase reactions of OH radicals with 2-propanol and three fluorine substituted 2-Propanols, (CH3)2CHOH (k0), CF3)2COH (k1), (CF3)2C(OH)CH3 (k2), and (CF3)3COH (k3) were measured using a flash photolysis resonance-fluorescence
Alexander M. Zolot, Fabrizio R. Giorgetta, Esther Baumann, Jeffrey W. Nicholson, William C. Swann, Ian R. Coddington, Nathan R. Newbury
We demonstrate a dual comb spectrometer using stabilized frequency combs spanning 176 THz to 219 THz (1370 nm to 1700 nm) in the near infrared. Measurements of amplitude and phase response at each individual comb tooth span the full 43 THz, generating ~430
Joseph N. Tan, Samuel M. Brewer, Nicholas D. Guise
Penning traps are made extremely compact by embedding rare-earth permanent magnets in the electrode structure. Axially-oriented NdFeB magnets are used to produce 0.32 T for ion trapping in unitary architectures that functionally couple the electric and
A. Cygan, D Lisak, S. Wojtewicz, J. Domyslawska, Joseph T. Hodges, R.S. Trawinski, R. Ciurylo
We present a new cavity-enhanced technique for the precise measurement of absorption line shape and line position. This approach, which combines high-bandwidth locking of a continuous wave probe laser with frequency-stabilized cavity ring-down spectroscopy
Alexander M. Zolot, Fabrizio R. Giorgetta, Esther Baumann, William C. Swann, Jeff Nicholson, Ian R. Coddington, Nathan R. Newbury
Most spectroscopic instruments directly measure optical wavelength, which is converted to frequency and calibrated against spectral features that have traditionally been measured using complicated frequency chain methods. In the past decade optical
Walter J. Lafferty, Jean-Marie Flaud, F. Kwabia Tchana, A. Perrin
Fourier transform spectra of Oxirane (ethylene oxide, c-C2H4O) have been recorded in the 730 cm-1 to 1560 cm-1 (6.4 to 13.7 µm) spectral region using a Bruker IFS125HR spectrometer at a resolution of 0.0019 cm-1. A total of six vibration bands, ν15, ν12
The energy levels and observed spectral lines of neutral and singly ionized titanium atoms have been compiled. Tables of energy levels and spectral lines are generated for each stage. Experimental g-factors and leading percentages are included when
The formation of ligand-protected transition metal nanoclusters in size-selective syntheses is driven by the inherent properties of the protecting ligands. We have previously reported the selective, monodisperse product formation of phosphine protected Au
Tracey Johnston, Sarah Newton, Karl Brenkert, John Leffler, Dan Bearden
Aquaculture produces a significant source of protein for global human consumption. Commercial fish diets rely heavily on fishmeal and fish oil, which can be costly. Alternative protein and lipid sources may provide nutritionally improved high performance
Kenneth O. Patten, Victor Khamaganov, Vladimir L. Orkin, Steven L. Baughcum, Donald J. Wuebbles
The rate constant for the gas phase reaction of OH radicals with BTP (2-Bromo-3,3,3-trifluoropropene, CH2=CBrCF3) was measured using a flash photolysis resonance-fluorescence technique over the temperature range 220 K to 370 K. The Arrhenius plot was found
Esther Baumann, Fabrizio R. Giorgetta, William C. Swann, Alexander M. Zolot, Ian R. Coddington, Nathan R. Newbury
We demonstrate a high-accuracy dual-comb spectrometer centered at 3.4 υm. The amplitude and phase spectra of the P,, Q, and partial R branches of the methane Ņ3 band are measured at 25 to 100 MHz point spacing with resolution under 10 kHz and a signal-to
Joshua Sebree, David F. Plusquellic, Timothy Zwier
With the growing interest in the role naphthalene may play in planetary atmospheres and the interstellar medium, it is important to characterize other C10H8 structural isomers. These C10H8 isomers, once formed, may undergo an isomerization reaction to form
Recent metabolomics research on the temperature-dependent coral pathogen Vibrio coralliilyticus has led to the discovery of several compounds produced by the organism as a response to high-density, low nutrient growing conditions. Three compounds
Eduard Rocas, Juan C. Collado Gomez, Jordi Mateu, Nate Orloff, James Booth, Juan M. O'C allaghan
"This work evaluates the microwave nonlinear properties and tuning at RF frequencies of ferroelectric Ba0.3Sr0.7TiO3 thin-films by on-wafer measurements of the second and third-order harmonics and intermodulation products of several coplanar transmission
Paul C. DeRose, Melody V. Smith, Klaus Mielenz, Jeffrey R. Anderson, Gary W. Kramer
Standard Reference Material (SRM) 2943 is a cuvette-shaped, Cu0ion-doped glass, recommended for use for relative spectral correction of emission and day-to-day performance verification of steady-state florescence spectrometers. Properties of this standard
Nicholas W. Ritchie, Dale E. Newbury, Abigail P. Lindstrom
Artifacts are the nemesis of trace element analysis in electron-excited energy dispersive x-ray spectrometry. Peaks which result from non-ideal behavior in the detector or sample can fool even an experience microanalyst into believing that they have trace