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You searched for: Subject term gases Remove constraint Subject term: gases Subject term ionization Remove constraint Subject term: ionization Text availability Citation in PubAg Remove constraint Text availability: Citation in PubAg
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1. A Reservoir of Ionized Gas in the Galactic Halo to Sustain Star Formation in the Milky Way

Author:
Nicolas Lehner; J. Christopher Howk
Source:
Science 2011 v.334 no.6058 pp. 955-958
ISSN:
0036-8075
Subject:
gases; ionization; telescopes
Abstract:
... Without a source of new gas, our Galaxy would exhaust its supply of gas through the formation of stars. Ionized gas clouds observed at high velocity may be a reservoir of such gas, but their distances are key for placing them in the galactic halo and unraveling their role. We have used the Hubble Space Telescope to blindly search for ionized high-velocity clouds (iHVCs) in the foreground of galact ...
DOI:
10.1126/science.1209069

2. A compact high resolution electrospray ionization ion mobility spectrometer

Author:
T. Reinecke; A.T. Kirk; A. Ahrens; C.-R. Raddatz; C. Thoben; S. Zimmermann
Source:
Talanta 2016 v.150 pp. 1-6
ISSN:
0039-9140
Subject:
ambient temperature; bentazon; droplets; electric field; evaporation; gases; halides; ionization; ions; methanol; solvents; spectrometers; tritium
Abstract:
... Electrospray is a commonly used ionization method for the analysis of liquids. An electrospray is a dispersed nebular of charged droplets produced under the influence of a strong electrical field. Subsequently, ions are produced in a complex process initiated by evaporation of neutral solvent molecules from these droplets. We coupled an electrospray ionization source to our previously described hi ...
DOI:
10.1016/j.talanta.2015.12.006

3. A mass spectrometric study and computer modeling of noncovalent interactions of cytosine with polyethylene glycol oligomers

Author:
V. G. Zobnina; V. V. Chagovets; O. A. Boryak; M. V. Kosevich
Source:
Journal of analytical chemistry 2015 v.70 no.13 pp. 1533-1541
ISSN:
1061-9348
Subject:
biophysics; computers; cytosine; evaporation; gases; ionization; mass spectrometry; methanol; molecular dynamics; molecular models; nanoparticles; nitrogen; nucleic acids; polyethylene glycol; protons; solvents
Abstract:
... Data on intermolecular noncovalent interactions of nitrogen base components of nucleic acid with organic polyethers are of interest both for fundamental molecular biophysics and for applications in the production of pharmaceutical organic nanoparticles. In the present work, systems composed of pyrimidine nitrogen base cytosine (Cyt) or its methyl derivatives and polyethylene glycol PEG-400 oligome ...
DOI:
10.1134/S1061934815130110

4. A method for quantitative analysis of gases evolving during formation applied on LiNi0.6Mn0.2Co0.2O2 ∣∣ natural graphite lithium ion battery cells using gas chromatography - barrier discharge ionization detector

Author:
Marco Leißing; Martin Winter; Simon Wiemers-Meyer; Sascha Nowak
Source:
Journal of chromatography 2020 v.1622 pp. 461122
ISSN:
0021-9673
Subject:
additives; anodes; calibration; cathodes; detection limit; electrolytes; gas chromatography; gases; graphene; hydrocarbons; ionic liquids; ionization; lithium batteries; mixing; quantitative analysis
Abstract:
... To understand the overall processes behind the decomposition of state-of-the-art organic liquid electrolytes in lithium ion batteries (LIBs), it is necessary to investigate and quantify the permanent gases and light hydrocarbons evolving during electrolyte decomposition. In this work a convenient way of sampling gas from pouch cells without any previous preparation of the cell as well as a compreh ...
DOI:
10.1016/j.chroma.2020.461122

5. A multichannel rotating electrospray ionization mass spectrometry (MRESI): instrumentation and plume interactions

Author:
Ran Qiu; Chengsen Zhang; Zhen Qin; Hai Luo
Source:
RSC advances 2016 v.6 no.43 pp. 36615-36622
ISSN:
2046-2069
Subject:
chemical species; desorption; droplets; electrospray ionization mass spectrometry; electrostatic interactions; gases; instrumentation; ionization; liquids; solvents
Abstract:
... A multichannel rotating electrospray ionization (MRESI) mass spectrometry method is described. It is carried out by rotating three spray emitters infused with the same or different kinds of solvents or solutions. Rotation effect is shown as a critical factor in equalizing the sampling processes from different channels. The interactions of plumes generated from different spray emitters in MRESI has ...
DOI:
10.1039/c6ra06471j

6. A neutralization-reionization and reactivity mass spectrometry study of the generation of neutral hydroxymethylene

Author:
Lin, Yawei; Crestoni, Maria Elisa; Fornarini, Simonetta; Mayer, Paul M.
Source:
Journal of mass spectrometry 2011 v.46 no.6 pp. 546-552
ISSN:
1076-5174
Subject:
dissociation; energy; formaldehyde; gases; ionization; ions; isotope labeling; isotopes; mass spectrometry; neutralization; protons; pyridines
Abstract:
... Neutral hydroxymethylene HCOH is an important intermediate in several chemical reactions; however, it is difficult to observe due to its high reactivity. In this work, neutral hydroxymethylene and formaldehyde were generated by charge exchange neutralization of their respective ionic counterparts and then were reionized and detected as positive-ion recovery signals in neutralization-reionization m ...
DOI:
10.1002/jms.1923

7. A pitfall of using 2-[(2E)-3-(4-tert-butylphenyl)-2-methylprop-2-enylidene]malononitrile as a matrix in MALDI TOF MS: chemical adduction of matrix to analyte amino groups

Author:
Lou, Xianwen; de Waal, Bas F.M.; van Dongen, Joost L.J.; Vekemans, Jef A.J.M.; Meijer, E.W.
Source:
Journal of mass spectrometry 2010 v.45 no.10 pp. 1195-1202
ISSN:
1076-5174
Subject:
aromatic amines; cations; desorption; gases; ionization; mass spectrometry; secondary amines; tertiary amines
Abstract:
... 2-[(2E)-3-(4-tert-Butylphenyl)-2-methylprop-2-enylidene]malononitrile (DCTB) has been considered as an excellent matrix for matrix-assisted laser desorption/ionization (MALDI) of many types of synthetic compounds. However, it might provide troublesome results for compounds containing aliphatic primary or secondary amino groups. For these compounds, strong extra ion peaks with a mass difference of ...
DOI:
10.1002/jms.1814

8. A simple approach to multifunctionalized N1-alkylated 7-amino-6-azaoxindole derivatives using their in situ stabilized tautomer form

Author:
Nikolay T. Tzvetkov; Beate Neumann; Hans-Georg Stammler; Liudmil Antonov
Source:
Tetrahedron 2016 v.72 pp. 6455-6466
ISSN:
0040-4020
Subject:
alkylation; chemical elements; chemical structure; gases; ionization; organic compounds; physicochemical properties
Abstract:
... A simple approach for the synthesis of multifunctionalized N1-alkyl 7-amino-6-azaoxindole derivatives was developed and investigated. Formation of 5-amino- and 7-amino-6-aza-2-oxindoles 12a and 13a, respectively, was achieved using an intramolecular reductive cyclization as a key step. Subsequent alkylation of the pyrrole N1 atom in 12a led to the desired N1-alkylated compounds 22a–24 comprising d ...
DOI:
10.1016/j.tet.2016.08.055

9. Ab initio investigations on the gas phase basicity and nonlinear optical properties of FLiₙOH species (n = 2–5)

Author:
Ambrish Kumar Srivastava; Neeraj Misra
Source:
RSC advances 2015 v.5 no.91 pp. 74206-74211
ISSN:
2046-2069
Subject:
alkalis; energy; gases; hydroxides; ionization; optical properties; salts; synthesis
Abstract:
... Superalkalies, due to lower ionization potentials than alkalies, possess potential reducing capability and can be used in the synthesis of a variety of charge transfer salts. In order to check whether superalkali hydroxides are as basic as a typical alkali hydroxide, we have performed a systematic investigation on the hydroxides of small FLiₙ (n = 2–5) superalkali clusters. The equilibrium structu ...
DOI:
10.1039/c5ra14735b

10. Ab initio quantum chemical study on the mechanism of exceptional behavior of lysine for ion yields in MALDI--role of vibrational entropic contribution in thermally averaged proton affinities

Author:
Hatakeyama, Makoto; Tachikawa, Masanori
Source:
Journal of mass spectrometry 2011 v.46 no.4 pp. 376-382
ISSN:
1076-5174
Subject:
Gibbs free energy; desorption; gases; hydrogen bonding; ionization; lysine; mass spectrometry; temperature
Abstract:
... To elucidate the mechanism of the exceptional behavior of lysine for the ionization (protonation) yields in matrix-assisted laser desorption/ionization (MALDI) observed by Nishikaze and Takayama [Rapid Commun. Mass Spectrom. 2006, 20, 376], the temperature dependences of proton affinity (PA) and gas phase basicity for 20 amino acids are theoretically analyzed with correlated ab initio molecular or ...
DOI:
10.1002/jms.1903

11. Accuracy of Ion Mobility Measurements Dependent on the Influence of Humidity

Author:
Mayer Thomas; Borsdorf Helko
Source:
Analytical chemistry 2014 v.86 no.10 pp. 5069-5076
ISSN:
1520-6882
Subject:
analytical chemistry; gases; humidity; ionization; ions; spectrometers
Abstract:
... Measurements with sensor techniques in field analytical chemistry can be considerably affected by varying ambient conditions such as humidity. We systematically investigated the way in which ion mobility measurements are influenced by moisture. Both the peak positions of product ions within the spectrum and their relative abundance can vary depending on humidity. The transportation of humidity via ...
DOI:
10.1021/ac5007393

12. Acylated glucosinolates with diverse acyl groups investigated by high resolution mass spectrometry and infrared multiphoton dissociation

Author:
Giuliana Bianco; Niels Agerbirk; Ilario Losito; Tommaso R.I. Cataldi
Source:
Phytochemistry 2014 v.100 pp. 92-102
ISSN:
0031-9422
Subject:
Barbarea vulgaris; dissociation; esterification; esters; gases; glucobrassicin; ionization; isomers; mass spectrometry; reversed-phase liquid chromatography; seeds; sinapic acid; substrate specificity
Abstract:
... With the aim of developing a procedure for detecting and identifying intact acylated glucosinolates (a-GLSs) found in trace quantities in natural plant samples, extracts of Barbarea vulgaris seeds were analyzed by reversed-phase liquid chromatography coupled with electrospray ionization and Fourier-transform ion cyclotron resonance mass spectrometry (RPLC-ESI FTICR MS). After a preliminary optimiz ...
DOI:
10.1016/j.phytochem.2014.01.010

13. Aliphatic and aromatic amines in atmospheric aerosol particles: Comparison of three ionization techniques in liquid chromatography-mass spectrometry and method development

Author:
José Ruiz-Jiménez; Sanna Hautala; Jevgeni Parshintsev; Totti Laitinen; Kari Hartonen; Tuukka Petäjä; Markku Kulmala; Marja-Liisa Riekkola
Source:
Talanta 2012 v.97 no. pp. 55-62
ISSN:
0039-9140
Subject:
aerosols; aromatic amines; atmospheric pressure; derivatization; gases; ionization; liquid chromatography; mass spectrometry
Abstract:
... A complete methodology was developed for the determination of ten aliphatic and nine aromatic amines in atmospheric aerosol particles. Before the liquid chromatography — tandem mass spectrometric separation and determination, the derivatization reaction of the analytes using dansyl chloride was accelerated by ultrasounds. From three different ionization techniques studied electrospray ionization w ...
DOI:
10.1016/j.talanta.2012.03.062

14. Ambient analysis by thermal desorption atmospheric pressure photoionization

Author:
Kaveh Jorabchi; Karl Hanold; Jack Syage
Source:
Analytical and bioanalytical chemistry 2013 v.405 no.22 pp. 7011-7018
ISSN:
1618-2642
Subject:
atmospheric pressure; desorption; gases; helium; ionization; ions; mass spectrometry; nitrogen; non-polar compounds; spectrometers; thermal analysis
Abstract:
... Ambient mass spectrometry has attracted substantial attention in recent years. Among ambient ionization methods, thermal desorption ionization stands out because of two attributes: (1) simplicity, rendering the technique suitable for in-field applications, and (2) ability to couple with a variety of gas-phase ionization methods thereby broadening the range of molecules that can be analyzed with th ...
DOI:
10.1007/s00216-012-6536-z

15. An Ammonium Bicarbonate-Enhanced Stable Isotope Dilution UHPLC-MS/MS Method for Sensitive and Accurate Quantification of Acrolein–DNA Adducts in Human Leukocytes

Author:
Yin Ruichuan; Liu Shengquan; Zhao Chao; Lu Meiling; Tang Moon-shong; Wang Hailin
Source:
Analytical chemistry 2013 v.85 no.6 pp. 3190-3197
ISSN:
1520-6882
Subject:
DNA; acrolein; ammonia; ammonium acetate; ammonium bicarbonate; ammonium salts; carbon dioxide; detection limit; electrospray ionization mass spectrometry; formates; formic acid; gases; humans; ionization; isotope dilution technique; leukocytes; mutagenicity; nucleotides; pollutants; stable isotopes; stereoisomers; ultra-performance liquid chromatography
Abstract:
... Acrolein (Acr), a ubiquitous environmental pollutant, can react directly with genomic DNA to form mutagenic adducts without undergoing metabolic activation. To sensitively and accurately quantify Acr–DNA adducts (including structural isomers and stereoisomers) in human leukocytes, we developed an enhanced stable isotope dilution ultrahigh performance liquid chromatography (UHPLC)–tandem mass spect ...
DOI:
10.1021/ac3034695

16. An Experimental and Computational Investigation into the Gas-Phase Acidities of Tyrosine and Phenylalanine: Three Structures for Deprotonated Tyrosine

Author:
Bokatzian Samantha S.; Stover Michele L.; Plummer Chelsea E.; Dixon David A.; Cassady Carolyn J.
Source:
Journal of physical chemistry 2014 v.118 no.44 pp. 12630-12643
ISSN:
1520-5207
Subject:
energy; gases; ionization; ions; mass spectrometry; phenylalanine; physical chemistry; solvents; tyrosine
Abstract:
... Using mass spectrometry and correlated molecular orbital theory, three deprotonated structures were revealed for the amino acid tyrosine. The structures were distinguished experimentally by ion/molecule reactions involving proton transfer and trimethylsilyl azide. Gas-phase acidities from proton transfer reactions and from G3(MP2) calculations generally agree well. The lowest energy structure, whi ...
DOI:
10.1021/jp510037c

17. An Experimental and Computational Study of the Gas-Phase Acidities of the Common Amino Acid Amides

Author:
Plummer Chelsea E.; Stover Michele L.; Bokatzian Samantha S.; Davis John T. M.; Dixon David A.; Cassady Carolyn J.
Source:
Journal of physical chemistry 2015 v.119 no.30 pp. 9661-9669
ISSN:
1520-5207
Subject:
amides; aspartic acid; cysteine; energy; gases; glutamic acid; histidine; ionization; ions; models; nitrogen; peptides; physical chemistry; proteins; spectrometers; tryptophan; tyrosine
Abstract:
... Using proton-transfer reactions in a Fourier transform ion cyclotron resonance mass spectrometer and correlated molecular orbital theory at the G3(MP2) level, gas-phase acidities (GAs) and the associated structures for amides corresponding to the common amino acids have been determined for the first time. These values are important because amino acid amides are models for residues in peptides and ...
DOI:
10.1021/acs.jpcb.5b04486

18. An approach toward quantification of organic compounds in complex environmental samples using high-resolution electrospray ionization mass spectrometry

Author:
Tran B. Nguyen; Sergey A. Nizkorodov; Alexander Laskin; Julia Laskin
Source:
Analytical methods 2012 v.5 no.1 pp. 72-80
ISSN:
1759-9679
Subject:
aerosols; calibration; chemical species; electrospray ionization mass spectrometry; gases; ionization; isoprene; molecular weight; photooxidation; quantitative analysis
Abstract:
... Quantitative analysis of individual compounds in complex mixtures using high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) is complicated by differences in the ionization efficiencies of analyte molecules, mainly resulting in signal suppression during ionization. However, the ability to obtain concentration estimates of compounds in environmental samples is important for data in ...
DOI:
10.1039/c2ay25682g

19. An investigation of thermochemical changes in Canadian hardwood species during wood welding

Author:
B. Belleville; T. Stevanovic; A. Cloutier; A. Pizzi; M. Prado; S. Erakovic; P. N. Diouf; M. Royer
Source:
European Journal of Wood and Wood Products 2013 v.71 no.2 pp. 245-257
ISSN:
0018-3768
Subject:
Acer saccharum subsp. saccharum; Betula alleghaniensis; Fourier transform infrared spectroscopy; X-ray photoelectron spectroscopy; carbohydrates; depolymerization; detectors; dowels; gas chromatography; gases; hardwood; ionization; mass spectrometry; mechanical properties; polymers; thermal conductivity; wood properties
Abstract:
... Thermochemical changes during wood-dowel welding were investigated in two Canadian hardwood species commonly used for indoor appearance applications: sugar maple (Acer saccharum) and yellow birch (Betula alleghaniensis). The original reference wood sample and the welded interface between two bonded wood pieces, a dowel and a substrate, were compared to explain differences in mechanical properties ...
DOI:
10.1007/s00107-013-0671-x

20. Analysis of Intrinsic Peptide Detectability via Integrated Label-Free and SRM-Based Absolute Quantitative Proteomics

Author:
Jarnuczak Andrew F.; Lee Dave C. H.; Lawless Craig; Holman Stephen W.; Eyers Claire E.; Hubbard Simon J.
Source:
Journal of Proteome Research 2016 v.15 no.9 pp. 2945-2959
ISSN:
1535-3907
Subject:
gases; hydrophobicity; ionization; ions; liquid chromatography; mass spectrometry; models; peptides; proteome; proteomics; yeasts
Abstract:
... Quantitative mass spectrometry-based proteomics of complex biological samples remains challenging in part due to the variability and charge competition arising during electrospray ionization (ESI) of peptides and the subsequent transfer and detection of ions. These issues preclude direct quantification from signal intensity alone in the absence of a standard. A deeper understanding of the governin ...
DOI:
10.1021/acs.jproteome.6b00048