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Shinichiro Muramoto, Thomas P. Forbes, Matthew E. Staymates, John G. Gillen
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used to characterize the desorption performance of two emerging ambient ionization mass spectrometry (MS) sources; desorption electrospray ionization (DESI) and low temperature plasma (LTP)
Li-Hong Xu, Ronald M. Lees, Jon T. Hougen, Joel M. Bowman, Xinchuan Huang, Stuart Carter
Comparison of graphical displays of normal-mode coefficients from recent quantum chemical projected-frequency calculations with analogous displays constructed after reexamination of results from more extensive higher-level calculations described earlier in
Jessica L. Burger, Raina V. Gough, Tara Lovestead, Thomas J. Bruno
Cetane number (CN) is a measure of the ignition quality of a fuel for compression ignition engines according to the self-ignition delay and serves a function similar to that of the octane rating method used for fuel for spark ignition engines. If the
Introduced here is a method for determining the solution conformational entropy of oligosaccharides (-S) that relies on the on-line coupling of size-exclusion chromatography (SEC), an entropically-controlled separation technique, and differential
Aaron M. Katzenmeyer, Jerome Canivet, Glenn Holland, David Farrusseng, Andrea Centrone
Metal-organic frameworks (MOFs), are crystalline, micro to mesoporous functional materials consisting of inorganic clusters interconnected by organic linkers. The possibility of tailoring the chemical functionality and pore size while maintaining the
Kurt D. Benkstein, Phillip H. Rogers, Christopher B. Montgomery, Jerry Jin, Baranidharan Raman, Stephen Semancik
The capabilities of a chemiresistive microsensor array for detecting and identifying four trace target analytes were examined under a simulated Martian atmosphere. The simulated environment included low oxygen content (0.15 %) balanced by carbon dioxide
We present a theoretical investigation of optical self-focusing effects in light scattering with condensates. Using long (>200 μs), red-detuned pulses we show numerically that a nonnegligible self-focusing effect is present that causes rapid optical beam
Rick L. Paul, William C. Davis, Karen E. Murphy, Colleen E. Bryan Sallee, Lee L. Yu, William F. Guthrie, Dennis D. Leber, Thomas W. Vetter
A newly developed procedure for determination of arsenic by radiochemical neutron activation analysis was used to measure arsenic in SRM 955c Toxic Elements in Caprine Blood and SRM 2668 Toxic Elements in Frozen Human Urine for the purpose of providing
Paul A. Rudnick, Xinjian Yan, Stephen E. Stein, Xia Wang, Nell Sedransk
Systematic biases, or batch effects, in high-throughput biological datasets can be described as obscuring variabilities introduced during experimental design or analytical processing. These biases, if left unresolved, can lead to misinterpretation of
James Radney, Rian You, Xiaofei Ma, Joseph Conny, Michael R. Zachariah, Joseph T. Hodges, Christopher D. Zangmeister
We measure the mass-specific absorption and extinction cross sections for laboratory-generated soot aerosols. Two soot morphologies are investigated, both comprising fractal aggregates of nearly spherical monomers. The first type consists of monomer chains
The absorption coefficient and mass specific absorption cross section were determined for nigrosin-laden quartz, Teflon, and polycarbonate filters in inert surroundings at different steady-state temperatures and particle mass loadings. The objective was to
George C. Rhoderick, David L. Duewer, Eric Apel, Annarita Baldan, Bradley Hall, Alice Harling, Detlev Helmig, Gwi S. Heo, Jacques Hueber, Mi E. Kim, Yong D. Kim, Benjamin Miller, Stephen Montzka, Daniel Reimer
Studies of climate change increasingly recognize the diverse influences of hydrocarbons in the atmosphere, including roles in particulates and ozone formation. Measurements of key non methane hydrocarbons (NMHCs) suggest atmospheric mole fractions ranging
Stephen E. Stein, David M. Bunk, Xia Wang, Matthew Chambers, Lorenzo J. Vega-Montoto, David L. Tabb
Shotgun proteomics experiments integrate a complex sequence of processes, any of which can introduce variability. Quality metrics computed from LC-MS/MS data have relied upon identifying MS/MS scans, but a new mode for the QuaMeter software produces
Alexander (. Vergara Tinoco, Fonollosa Jordi, Huerta Ramon, Santiago Marco
Definitions of the Limit of Detection (LoD) based on the probability of false positive and/or false negative errors have been proposed over the past years. Although such definitions are straightforward and valid for any kind of analytical system, the
Elyssia S. Gallagher, Elisabeth Mansfield, Craig A. Aspinwall
Transmembrane protein (TMP)-functionalized analytical platforms represent a powerful new paradigm in chemical analysis. Of particular interest is the development of high throughput, TMP-functionalized stationary phases for affinity chromatography of
RATIONALE: N-Alkylation of sulfonylbenzamides was reported recently to cause a dramatic and surprising change in electron ionization mass spectrometry (EIMS), leading to a closed-shell base peak. Only an incomplete, speculative mechanism was available at
Elyssia S. Gallagher, Seid M. Adem, Leonard K. Bright, Elisabeth Mansfield, Craig A. Aspinwall
Separations of proteins and peptides in capillary zone electrophoresis suffer from non-specific adsorption of the analytes to the capillary surface. Semi-permanent phospholipid bilayers have been used to minimize adsorption, but must be regenerated
Yoana Y. Nuevo Ordonez, William C. Davis, Raymond F. Anton
Carbohydrate deficient transferrin (CDT) measurements in human serum constitute the most specific marker for chronic heavy alcohol use and congenital disorders of glycosylation in proteins. Therefore, the development of precise and accurate analytical
Ryan C. Nieuwendaal, Chad R. Snyder, Dean M. DeLongchamp
We report on details of molecular packing in high molar mass poly(3-hexylthiophene) (P3HT) by solid-state 13C {1H} cross-polarization magic angle spinning (CPMAS) NMR measurements. The degree of polymer order was estimated for two films of varied drying
Benjamin B. Parrott, John Bowden, Satomi Kohno, Jessica A. Cloy-McCoy, Jacqueline T. Bangma, Thomas R. Rainwater, Phillip M. Wilkinson, John Kucklick, Louis J. Guillette
Epigenetic modifications are key mediators of the interactions between the environment and an organism's genome. DNA methylation represents the best-studied epigenetic modification to date and is known to play key roles in regulating transcriptional
Brent A. Sperling, William A. Kimes, James E. Maslar
Infrared spectroscopy has been widely used for in situ analysis of the gas phase during chemical vapor deposition (CVD) and atomic layer deposition (ALD). For both process monitoring and research applications, accurate determination of absorptivity is
Steve Y. Rhieu, Aaron A. Urbas, Daniel W. Bearden, John P. Marino, Vytautas Reipa, Katrice A. Lippa
Non-invasive and real-time analysis of cellular redox processes has been greatly hampered by lack of suitable measurement techniques. Here we describe an in-cell nuclear magnetic resonance (NMR)-based method for measuring the intracellular glutathione
Second order nonlinear spectroscopies such as sum frequency generation (SFG) are intrinsically interface sensitive and enable sub monolayer sensitivity to be achieved at buried, optically accessible interfaces. Vibrationally-resonant SFG allows bond
Thomas J. Bruno, Benjamin Kehimkar, Jamin C. Hoggard, Luke C. Marney, M. C. Billingsley, C. G. Fraga, R. E. Synovec
There is an increased need to more fully assess and control the composition of kerosene-based rocket propulsion fuels such as RP-1. In particular, it is critical to make better quantitative connections among the following three attributes: fuel performance
Rusen Yan, Jeffrey R. Simpson, Simone Bertolazzi, Jacopo Brivio, Michael Watson, Xufei Wu, Andras Kis, Tengfei Luo, Angela R. Hight Walker, Huili G. Xing
Atomically thin molybdenum disulphide (MoS2) is emerging as a potential alternative to graphene due to presence of bandgap, which is particularly advantageous to optoelectronic applications. The temperature-dependent Raman spectra of exfoliated monolayer