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Walter J. Lafferty, Jean-Marie Flaud, F. Kwabia Tchana, L. Manceron
Fourier transform spectra of phosgene (Cl2CO) have been recorded in the 11.75 μm and 5.47 μm spectral regions using a Bruker IFS125HR spectrometer at resolutions of 0.00102 cm-1 and 0.0015 cm-1 respectively leading to the observation of the ν5 and ν1
Pawel Jaruga, Natalie R. Gassman, Erdem Coskun, Donna F. Stefanick, Julie K. Horton, M Miral Dizdar, Samuel H. Wilson
Metabolism of bisphenol A (BPA) generates reactive oxygen species causing DNA strand breaks and damaged DNA bases. Base excision repair (BER) is responsible for removing oxidatively induced DNA base lesions and for repairing single strand breaks (SSBs)
The National Institute of Standards and Technology (NIST) has established a Vitamin D Metabolites Quality Assurance Program (VitDQAP) in collaboration with the National Institutes of Health (NIH) Office of Dietary Supplements. Participants in the seventh
Yuxue Liang, Pedatsur Neta, Yamil Simon, Stephen E. Stein
RATIONALE: Tandem mass spectra of many compounds contained peaks which could not arise from the precursor ion and were different in different instruments. Such peaks were found to be due to reaction of arylium ions with N2 in the collision cell. Therefore
Lucy J. Carpenter, Stefan Reimann, Andreas Engel, Stephen Montzka, James B. Burkholder, Cathy Clerbaux, Bradley Hall, Shari A. Yvon-Lewis, Donald R. Blake, Marcel Dorf, Geoffre S. Dutton, Paul J. Fraser, Lucien Froidevaux, Fran?ois Hendrick, Jianxin Hu, Ashley Jones, Paul B. Krummel, Lambert J. Kuijpers, Michael J. Kurylo, Qing Liang, Emmanuel Mahieu, Jens M?hle, Simon O?Doherty, Keiichi Ohnishi, Vladimir L. Orkin, Klaus Pfeilsticker, Matt Rigby, Isobel J. Simpson, Yoko Yokouchi
Changes in the global atmospheric abundance of a substance are determined by the balance between its emissions and removal. Declines observed for ozone-depleting substances (ODSs) controlled under the Montreal Protocol are due to global emission reductions
Walter R. Miller Jr., George C. Rhoderick, Franklin R. Guenther
Between June 2010 and June 2011, the National Institute of Standards and Technology gravimetrically prepared a suite of 20 carbon dioxide [CO2] in air primary standard mixtures [PSMs]. Ambient mole fraction levels were obtained through six levels of
Walter J. Lafferty, Jean-Marie Flaud, Fridolin Kwabia
Absolute individual line intensities of numerous transitions of the fundamental ν15, ν12 and ν5 bands of oxirane (ethylene oxide, cyc-C2H4O) have been measured in the 790-940 cm-1 region using seven high-resolution Fourier transform spectra recorded at 0
V. Goian, S. Kamba, D Nuzhnyy, Nathan Orloff, T. Birol, C.-H Lee, D. G. Schlom, James Booth
Recently, Lee et al. [1] used1% tensile strain to induce a ferroelectic instability in thin films of Srdn+1uTi nuO 3n+1u (n=1-6) phases. They showed that the Curie temperature T cu gradually increased with n, reaching 180 K for Sr7Ti6O19 (n=6). The
Vladimir L. Orkin, Victor Khamaganov, A G. Guschin
Rate constants for the gas phase reactions of OH radicals with three partially fluorinated ethers, CH3OCF3 (kHFE-143a), CH3OCHF2 (kHFE-152a), and CHF2OCH2CF3 (kHFE-245fa), were measured using a discharge flow electron paramagnetic resonance technique
Pedatsur Neta, Yamil Simon, Yuxue Liang, Stephen Stein
Electrospray ionization mass spectrometry of 3-formylchromones and 3-formylcoumarins shows that collision-induced dissociation of the protonated ions results in elimination of H¬¬2 as a major fragmentation route. This loss of H2 yields an unstable carbonyl
David L. Duewer, Kenneth W. Pratt, Chainarong Cherdchu, Nongluck Tangpaisarnkul2 Nongluck Tangpaisarnkul2, Akiharu Hioki, Masaki Ohata, Petra Spitzer, Michal M?ri?ssy, Leo? Vysko?il
The Key Comparison (KC) studies of the Consultative Committee for Amount of Substance Metrology in Chemistry (CCQM) help ensure the reliability of chemical and biochemical measurements relevant to international trade and environmental , health , and
S. Avgeri, Marc J. Assael, Marcia L. Huber, Richard A. Perkins
This paper contains new, representative reference equations for the viscosity of benzene. The equations are based in part upon a body of experimental data that has been critically assessed for internal consistency and for agreement with theory whenever
David J. Vanderah, Marlon L. Walker, David T. Gallagher, Ryan Vierling, Fay Crawshaw
Spectroscopic ellipsometry was used to evaluate the resistance to protein adsorption (RPA) of self- assembled monolayers (SAMs) of HS(CH2)3O(CH2CH2O)6M and [HS(CH2)3CH]2O-(CH2CH2O)6M, where M = CH3 or H, on Au. The SAMs were exposed to fibrinogen, a
Jack A. Stone Jr., Patrick F. Egan, Jay H. Hendricks, Gregory F. Strouse, Douglas A. Olson, Jacob E. Ricker, Gregory E. Scace, Donavon Gerty
An apparatus capable of comparing displacements with picometer accuracy is currently being designed at NIST. In principle, we wish to compare one displacement in vacuum to a second, equal displacement in gas, in order to determine gas refractive index. If
Anzor I. Mikaia, Leonid S. Glebov, Vladimir G. Zaikin, George A. Kliger
A new reductive dimerization and oligomerization reaction of (C5 and C6) cycloalkanols and cycloalkanones, benzaldehyde, and benzyl alcohol to hydrocarbons containing as many, or more, carbon atoms as the reactant oxygenated compound on a promoted, fused
Christopher W. Szakal, Lyubov Tsytsikova, David Carlander, Timothy V. Duncan
This article is one of a series of 4 that report on a task of the NanoRelease Food Additive (NRFA) project of the International. Life Science Institute Center for Risk Science Innovation and Application. The project aims are to identify, evaluate, and
This chapter reviews the currently available information concerning the behavior of transport properties near the vapor-liquid critical point of fluids and fluid mixtures. Special attention is devoted to the behavior of the thermal conductivity which
Engineered safety equipment is preferred over the reliance on personal protective equipment, and the fume hood is one such engineered safety device that is nearly ubiquitous in laboratories. Laboratories concerned with biological specimens (microbes
The literature of gas and liquid chromatography frequently contains schematic diagrams that depict analytical apparatus and peripherals. The interpretation of such diagrams can be facilitated by the following graphics that show the most common symbols used
In the interpretation of results from a particular technique, one often must evaluate the performance of the measurement on the basis of objective measures that are called figures of merit. The following table provides a description of the more common
Xiaoyu (Sara) Yang, Pedatsur Neta, Stephen E. Stein
Electrospray ionization (ESI) tandem mass spectrometry coupled with liquid chromatography is a routine technique for identifying and quantifying compounds in complex mixtures. The identification step can be aided by matching acquired tandem mass spectra
Because of the very powerful and common application of mass spectrometry with gas chromatography, the various technologies warrant more detailed consideration.[1-4] The following table provides basic information on the capabilities and applicability of the
This article reviews the early history of radiation-induced sugar damage in DNA in dedication to Prof. Clemens von Sonntag, who recently passed away. It covers the ten years between 1968 and 1978, during which most of the work on the ionizing radiation
Measurements of total pH, pHT, in electrochemical cells without transference are reported for 2 amino-2-hydroxymethyl 1,3-propanediol (Tris) buffers in synthetic seawater (SSW) of salinity 35 at three molality ratios of Tris to TrisHCl: 0.03:0.05, 0.04
Iulia A. Sacui, Jeffrey W. Gilman, Ryan C. Nieuwendaal, Stephan J. Stranick, Henryk Szmacinski, Mehdi Jorfi, Christopher Weder, Johan Foster, Richard Olsson, Daniel Burnett
This work describes the study and characterization of native cellulose nanocrystals and nanofibrils (CNCs, CNFs), whose crystallinity, morphology, aspect ratio, and surface chemistry depend on the raw material source and hydrolysis conditions. Measurement