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Age dating of fingerprints can have a significant impact in forensic science, as it has the potential to facilitate the judicial process by assessing the relevance of a fingerprint found in a crime scene. However, no reliable method currently exists that
Nino G. Todua, Kirill V. Tretyakov, Anzor I. Mikaia
The central mission for the development of the NIST/NIH/EPA mass spectral library (The Library) is the acquisition of reference GC-MS data for important compounds and their chemical modification products 1. Addition of reliable reference data of various
Examined here is the feasibility of employing Raman spectroscopy as a detection method in size- exclusion chromatography (SEC) and related macromolecular separations, for the purposes of determining the chemical heterogeneity of copolymers. To this effect
We demonstrate a method to measure the absorption spectra of gas and aerosol species across the visible and near-IR (500 to 840 nm) using a photoacoustic (PA) spectrometer and a pulsed supercontinuum laser source. Measurements of gas phase absorption
Peter Y. Hsieh, Jason Widegren, Andrew Slifka, Andrew J. Hagen, Ronald A. Rorrer
Surface-active trace compounds present in diesel fuels protect pumps and injectors against premature wear through boundary lubrication. Due to the vast number of hydrocarbon compounds found in petroleum distillate fuels, it is difficult to measure the
Stephen A. Wise, Lane C. Sander, Michele M. Schantz
Since identified as priority pollutants by the U.S. Environmental Protection Agency (EPA) in 1979, the 16 EPA polycyclic aromatic hydrocarbons (PAHs) have been a key motivation for analytical methods development for the determination of PAHs. In this
Alfons Weber, A. Maki, J. E. Price, Jared Harzan, J. W. Nibler, T. Masiello, T Blake
The high resolution absorption spectrum of spiropentane (C5H8) from 200 cm-1 to 4000 cm−1 has been measured and a detailed analysis is presented for eight bands in the region from 700 cm−1 to 2200 cm−1. Two fundamental perpendicular bands were analyzed
The following table provides guidance in the recognition and interpretation of spurious signals (m/z peaks) that will sometimes be observed in mass spectra, especially mass spectra obtained from gas chromatography mass spectrometry systems (GC-MS) [1,2]
While trapping sorbents have been used for many years in headspace analysis (most commonly with gas chromatography), the modern techniques of solid phase microanalysis (SPME) are particularly applicable to survey analyses [1]. In the following tables, we
The practical application of solid adsorbents in capillary chromatography typically makes use of porous layer open tubular (PLOT) columns. Early capillary PLOT columns suffered from detector spiking due to particulates becoming dislodged and entering the
Much has been written over the last two decades about the advantages of separation orthogonality for the characterization of complex polymers and blends, and of the additive and synergistic benefits of combining various physical and chemical detection
Hyuk-Jae Jang, Jun-Sik Lee, Sujitra J. Pookpanratana, Ich C. Tran, Curt A. Richter, Christina A. Hacker
We present the results of experiments that explore the influence of molecular self-assembled monolayers (SAMs) on characteristics of spin injection into an organic semiconductor, Alq3 [tris-(8-hydroxyquinoline) aluminum] from a ferromagnetic metal, Co. Two
Mark S. Lowenthal, Eric L. Kilpatrick, Karen W. Phinney
Chromatographic separation of monosaccharides hydrolyzed from glycoconjugates or complex, aggregate biomaterials, can be achieved by classic analytical methods without a need for derivatizing the monosaccharide subunits. A simple and sensitive method is
Walter J. Lafferty, Jean-Marie Flaud, F. K. Kwabia Tchana
Fourier transform spectra of oxirane (ethylene oxide, c-C2H4O) have been recorded in the 3.17 μm - 3.5 μm region with a resolution of 0.005 cm-1. In addition, a Raman spectrum covering the same spectral region was recorded at a resolution of 0.44 cm-1
This chapter will provide an overview of the thermal techniques available to study nanoparticles, including thermogravimetric analysis, calorimetry and differential scanning calorimetry. The use of thermoanalysis for the measurement of nanoparticle purity
Raman scattering provides an intrinsic fingerprint of chemical composition. Spontaneous Raman spectroscopy has been used for many decades to interrogate biological materials and systems, but is not widely used for imaging due to relatively slow signal
Shinichiro Muramoto, Thomas Forbes, Arian C. van Asten, John Gillen
A novel standard for the forensic analysis of fingerprints was introduced and characterized using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and desorption electrospray ionization mass spectrometry (DESI-MS), aimed at the trace level
Jason P. Campbell, Jason T. Ryan, Pragya R. Shrestha, Zhanglong Liu, Canute I. Vaz, Jihong Kim, Vasileia Georgiou, Kin P. Cheung
Electron spin resonance (ESR) spectroscopys affinity for detecting paramagnetic free radicals, or spins, has been increasingly employed to examine a large variety of biochemical interactions. Such paramagnetic species are broadly found in nature and can
The first measurements of perfluorinated compounds (PFCs) in wildlife from the aqueous and terrestrial environment showed their ubiquitous presence. Since the initial studies in 2001 their presence, distribution, and fate in the environment has broadly
Lee J. Richter, Dean M. DeLongchamp, Natalie Stingelin, Alberto Salleo, Martin Heeney, Aram Amassian, John deMello, James Bannock, Fiona H. Scholes, Scott Watkins, Zhuping Fei, Koen Vandewal
ABSTRACT: Here, we show that the Charge Transfer (CT) absorption signal in bulk (BHJ) solar cell blends, measured by photothermal deflection spectroscopy (PDS), is directly proportional to the density of molecular donor/acceptor interfaces. Since the
Direct analysis in real time (DART) mass spectrometry was used for trace detection of the nitrate ester explosive, erythritol tetranitrate (ETN), and its sugar alcohol precursor, erythritol. The present investigation revealed the impact of competitive
Rick L. Paul, Rabia Oflaz, Jan Kucera, J W Bennett, E. A. De Nadai Fernandes, M. Kubesova, M. A. Bacchi, A. J. Stopic, R. E. Sturgeon, P. Grinberg
Instrumental neutron activation analysis with both relative and k0 standardization was used in four experienced laboratories to determine element mass fractions in single-wall carbon nanotube certified reference material (CRM) SWCNT-1. Results obtained