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Column selection is probably the single most important aspect of method development that will directly affect measurement accuracy and precision of liquid chromatographic (LC) measurements. An understanding of physical and chemical properties of LC columns
Joshua R. Biller, Karl F. Stupic, Anthony B. Kos, Timothy Weilert, George Rinard, Yoshi Nakashima, John M. Moreland
A low-field nuclear magnetic resonance (NMR) instrument is an important tool for investigating a wide variety of samples under different conditions. In this paper, we describe a system constructed primarily with commercially available hardware and control
New wavelength measurements in the vacuum ultraviolet (VUV), ultraviolet and visible spectral regions have been combined with available literature data to refine and extend the description of the spectrum of singly ionized copper (Cu II). In the VUV region
Rohit J. Jacob, Diana Ortiz-Montalvo, Kyle R. Overdeep, Timothy P. Weihs, Michael R. Zachariah
Exothermic reactions between oxophilic metals and transition/ post transition metal-oxides have been well documented owing to their fast reaction time scales (10 μs). This article examines the extent of reaction in nano-aluminum based thermite systems
Gillian Nave, Craig J. Sansonetti, Keeley I. Townley-Smith, J C. Pickering, Florence Liggins, Anne P. Thorne, Christian Clear
We summarize recent work at the National Institute of Standards and Technology and Imperial College London on wavelengths, hyperfi ne structure, energy levels, and analysis of singly-ionized iron-group elements of astrophysical interest.
James E. Lawler, Chris Sneden, Gillian Nave, E. A. Den Hartog, N Emrahoglu, John J. Cowan
New emission branching fraction (BF) measurements for 183 lines of the second spectrum of chromium (Cr II) and new radiative lifetime measurements from laser induced fluorescence for eight levels of the z4F and z4D levels of ionized Cr are reported. The
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
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
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
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
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
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
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