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Displaying 401 - 425 of 911

Least Squares Moving-Window Spectral Analysis

January 20, 2017

Author(s)

Young J. Lee

Least squares regression is proposed as a moving-windows method for analysis of a series of spectra acquired as a function of external perturbation. The least squares moving-window (LSMW) method can be considered an extended form of the SavitzkyGolay

First analysis of the rotationally-resolved n2 and 2n2- n2 bands of sulfur dioxide, 33S16O2

January 3, 2017

Author(s)

Thomas A. Blake, Jean-Marie Flaud, Walter J. Lafferty

A Fourier transform spectrum of sulfur dioxide 33S16O2 has been recorded in the 18.3 µm spectral region at a resolution of 0.002 cm-1 using a Bruker IFS 125HR spectrometer leading to the observation of the ν2 and 2ν2- ν2 vibrational bands of the 33S16O2

Gas-phase broadband spectroscopy using active sources: progress, status, and applications

January 1, 2017

Author(s)

Kevin C. Cossel, Eleanor M. Waxman, Ian A. Finneran, Geoffery A. Blake, Jun Ye, Nathan R. Newbury

Broadband spectroscopy is an invaluable tool for measuring multiple gas-phase species simultaneously. In this work we review current applications for broad-band spectroscopy. We discuss components of broad-band spectroscopy including light sources

A scoring metric for multivariate data for reproducibility analysis using chemometric methods

December 23, 2016

Author(s)

David A. Sheen, Werickson Fortunato de Carvalho Rocha, Katrice A. Lippa, Dan Bearden

Process quality control and reproducibility in emerging measurement fields such as metabolomics is normally assured by interlaboratory comparison testing. As a part of this testing process, spectral features from a spectroscopic method such as nuclear

Multiplexed sub-Doppler spectroscopy with an optical frequency comb

December 13, 2016

Author(s)

David A. Long, Adam J. Fleisher, David F. Plusquellic, Joseph T. Hodges

An optical frequency comb generated with an electro-optic phase modulator and a chirped radiofrequency waveform is used to perform saturation spectroscopy on the D1 and D2 transitions of atomic potassium. With a comb tooth spacing of 2 MHz and a bandwidth

Interpenetrating polyaniline-gold electrodes for SERS and electrochemical measurements

November 30, 2016

Author(s)

Ryan West, Stephen Semancik

Facile fabrication of nanostructured electrode arrays is critical for development of bimodal SERS and electrochemical biosensors. In this paper, the variation of applied potential at a polyaniline- coated Pt electrode is used to selectivity deposit Au on

Sparse multidimensional iterative lineshape-enhanced (SMILE) reconstruction of both non-uniformly sampled and conventional NMR data

November 19, 2016

Author(s)

Jinfa Ying, Frank Delaglio, Dennis Torchia, Adriaan Bax

Implementation of a new algorithm, SMILE, is described for reconstruction of non-uniformly sampled two-, three- and four-dimensional NMR data, which takes advantage of the known phases of the NMR spectrum and the exponential decay of underlying time domain

Thermal Decomposition Kinetics of Polyol Ester Lubricants

November 18, 2016

Author(s)

Kimberly N. Urness, Raina V. Gough, Jason A. Widegren, Thomas J. Bruno

Synthetic lubricants are widely used for applications that require high-thermal and oxidative stability. In order to facilitate new designs and applications for these fluids we are measuring a suite of thermophysical and transport properties for lubricant

Integration of Redox-Active Diruthenium-based Molecular Layer onto Electrodes for Memory Device Applications

November 10, 2016

Author(s)

Sujitra J. Pookpanratana, Hao Zhu, Joseph W. Robertson, Sean Natoli, Emily G. Bittle, Curt A. Richter, Tong Ren, Qiliang Li, Christina A. Hacker

Attaching and integrating electrochemically-active molecules to a variety of different surfaces is of importance for applications in catalysis, memory devices, and molecular electronics. With the increasing demand for personal electronics, growth in Flash

Phase-specific Raman analysis of n-alkane melting by moving-window two-dimensional correlation spectroscopy

November 9, 2016

Author(s)

Ying Jin, Anthony Kotula, Angela R. Hight Walker, Kalman D. Migler, Young Jong Lee

We usemoving-window two-dimensional correlation spectroscopy (MW-2DCOS) for phase-specific Raman analysis of the n-alkane (C21H44) duringmelting from the crystalline solid phase to the intermediate rotator phase and to the amorphousmolten phase. In MW

VECSEL systems for generation and manipulation of trapped magnesium ions

November 8, 2016

Author(s)

Shaun C. Burd, David T. Allcock, Tomi Leinonen, Jussi-Pekka Penttinen, Daniel H. Slichter, Raghavendra Srinivas, Andrew C. Wilson, Robert Jordens, Micrea Guina, Dietrich G. Leibfried, David J. Wineland

Experiments in atomic, molecular, and optical (AMO) physics rely on lasers at many different wave- lengths and with varying requirements on spectral linewidth, power and intensity stability. Vertical external-cavity surface-emitting lasers (VECSELs), when

Identification of the Crystal Symmetry in 1T' MoTe2 with Polarization-Resolved Second Harmonic Generation and Raman Scattering

October 13, 2016

Author(s)

Ryan Beams, Luiz Gustavo Cancado, Sergiy Krylyuk, Irina Kalish, Berc Kalanyan, Arunima Singh, Kamal Choudhary, Patrick Vora, Francesca M. Tavazza, Albert Davydov, Stephan J. Stranick

We study the crystal symmetry properties of few-layer 1T' MoTe2 using the polarization dependence of the second harmonic generation (SHG) and Raman scattering. Bulk 1T' MoTe2 is know to be inversion symmetric, however, we nd that the inversion symmetry is

Supramolecular Hemicage Cobalt Mediators for Efficient and Stable Dye-Sensitized Solar Cells

October 11, 2016

Author(s)

Lisa A. Fredin, Marina Freitag, Wenxing Yang, Luca D' Amario, K. Martin Karlsson, Anders Hagfeldt, Gerrit Boschloo

A new class of DSCs using the hemicage cobalt based mediator [Co(ttb)] 2+/3+ using the hexadentate ligand 5,5'',5''''-((2,4,6- triethyl highly preorganized benzene-1,3,5-triyl)tris(ethane-2,1- diyl))tri-2,2'- bipyridine (ttb) were studied. Current-voltage

Light Source Effects on Aerosol Photoacoustic Spectroscopy Measurements

October 6, 2016

Author(s)

James G. Radney, Christopher D. Zangmeister

Photoacoustic spectroscopy measurements of flame-generated soot aerosol coated with small amounts of water yielded absorption enhancements that were dependent on the laser used: quasi- continuous wave (Q-CW, ≈ 650 ps pulse duration and 78 MHz repetition

The rheo-Raman microscope: Simultaneous chemical, conformational, mechanical, and microstructural measures of soft materials

October 4, 2016

Author(s)

Anthony P. Kotula, Matthew Meyer, Francesca De Vito, Jan Plog, Angela R. Hight Walker, Kalman D. Migler

We describe the design and demonstrate performance of an instrument capable of simultaneous Raman spectroscopy, rheology, and optical microscopy of materials. The instrument couples a Raman microscope with a rotational rheometer through an optically

Broadband Coherent Anti-Stokes Raman Scattering

August 11, 2016

Author(s)

Charles H. Camp

Broadband coherent anti-Stokes Raman scattering (BCARS) microspectroscopy is a unique label-free imaging modality that provides detailed chemical information at each pixel. In minutes, this technique captures a hyperspectral cube that co-registers

Ground-based, integrated path differential absorption LIDAR measurement of CO2, CH4, and H2O near 1.6 mm

August 5, 2016

Author(s)

Gerd A. Wagner, David F. Plusquellic

The eye-safe transmitter of a ground-based, integrated path differential absorption (IPDA) LIDAR (light detection and ranging) system is described and specified in detail. The transmitter is based on an actively stabilized, continuous-wave, single

Prediction of the UltravioletVisible Absorption Spectra of Polycyclic Aromatic Hydrocarbons (Dibenzo and Naphtho) Derivatives of Fluoranthene

August 3, 2016

Author(s)

Jorge O. Ona Ruales, Yosadara Ruiz-Morales

The annellation theory method has been used to predict the locations of maximum absorbance (LMA) of the ultravioletvisible (UV-Vis) spectral bands in the group of polycyclic aromatic hydrocarbons (PAHs) C24H14 (dibenzo and naphtho)derivatives of

Torsionally mediated spin-rotation hyperfine splittings at moderate to high J values in methanol

July 13, 2016

Author(s)

Sergey P. Belov, Alexandr V. Lapinov, Arthur A. Mescheryakov, Jon T. Hougen, Li-Hong Xu

This paper presents an explanation based on torsionally mediated proton-spinoverall-rotation interaction for the observation of doublet hyperfine splittings in some Lamb-dip sub-millimeter-wave transitions between ground-state torsion-rotation states of E

Measured Wavelength-Dependent Absorption Enhancement of Internally Mixed Black Carbon with Absorbing and Nonabsorbing Materials

June 30, 2016

Author(s)

Rian You, James Radney, Michael R. Zachariah, Christopher D. Zangmeister

Optical absorption spectra of laboratory generated aerosols consisting of black carbon (BC) internally mixed with nonabsorbing materials (ammonium sulfate, AS, and sodium chloride, NaCl) and BC with a weakly absorbing brown carbon surrogate derived from

Measuring multiple, weak heteronuclear 13C-2H couplings involving large 2H quadrupolar coupling constants and large 13C chemical shift anisotropy values: An experimental and theoretical REDOR study

June 30, 2016

Author(s)

Ryan C. Nieuwendaal

We discuss the implementation of a REDOR experiment that is capable of measuring multiple, weak 13C-2H dipolar couplings when 2H is a strong quadrupole and 13C exhibits large chemical shift anisotropy. We find that at 7.05 T in the presence of large 13C

Evaluating the Oxidative Potential of Indoor and Outdoor Particles with an EPR Assay

June 19, 2016

Author(s)

Shahana S. Khurshid, Steven Emmerich, Andrew K. Persily

The hydroxyl radical (OH) generating capacity of particles has been measured in several outdoor locations, but it remains unquantified in indoor environments where extended periods of exposure are likely. Total suspended particle samples were collected

Low Temperature Ionic Conductivity of an Acceptor Doped Perovskite Part II: Impedance Spectroscopy of Single Crystalline BaTiO3

June 16, 2016

Author(s)

Russell A. Maier

Low temperature conductivity mechanisms are identified in acceptor doped BaTiO3 single crystals equilibrated and quenched from high temperature under different oxygen partial pressures. A range of acceptor ionization states are quenched into samples doped

Hyperfine structure constants for singly-ionized manganese (Mn II) using Fourier Transform Spectroscopy

June 9, 2016

Author(s)

Keeley I. Townley-Smith, Gillian Nave, J C. Pickering, Richard J. Blackwell-Whitehead

We expand on the comprehensive study of hyperfi ne structure (HFS) in Mn II conducted by Holt et al. (1999) by verifying hyper fine magnetic dipole constants (A) for 20 levels previously measured by Holt et al. (1999) and deriving A constants for 47

XAFS Data Interchange: A single spectrum XAFS data file format

June 9, 2016

Author(s)

Bruce D. Ravel, M. Newville

We propose a standard data format for the interchange of XAFS data. The XAFS Data Interchange (XDI) standard is meant to encapsulate a single spectrum of XAFS along with relevant metadata. XDI is a text-based format with a simple syntax which clearly