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1. Gas Chromatographic Analysis of Soil Atmospheres

Author:
A. M. Blackmer; J. M. Bremner
Source:
Soil Science Society of America journal 1977 v.41 no.5 pp. 908-912
ISSN:
0361-5995
Subject:
argon (noble gases); carbon dioxide; detectors; gas chromatography; gases; helium; ionization; methane; nitrogen; nitrous oxide; soil; streams; temperature; thermal conductivity; ultrasonics
Abstract:
... A gas chromatographic procedure is described that permits rapid, specific, and precise determination of N₂, O₂, Ar, CO₂, CH₄, N₂O, and other gases in soil atmospheres. It involves use of an ultrasonic detector and two columns of Porapak Q at different temperatures, and it does not require temperature programming, column conditioning, stream splitting, column switching, or switching of recorder pol ...
DOI:
10.2136/sssaj1977.03615995004100050019x

2. Determination of acetone, 2-butanone, diethyl ketone and BTX using HSCC-UV-IMS

Author:
Z. Xie; S. Sielemann; H. Schmidt; F. Li; J.I. Baumbach
Source:
Analytical and bioanalytical chemistry 2002 v.372 no.5-6 pp. 606-610
ISSN:
1618-2642
Subject:
acetone; benzene; detection limit; gases; humans; ionization; nitrogen; toluene; volatile organic compounds; xylene
Abstract:
... A combination of a custom-designed ion mobility spectrometer (IMS) with a UV ionization source and a high speed capillary column (HSCC) has been developed as an analytical device for the sensitive detection of volatile organic compounds (VOCs), e.g. 2-propanone (acetone), 2-butanone and 3-pentanone (diethyl ketone) in the gas phase. A fast separation of the three selected substances and benzene, t ...
DOI:
10.1007/s00216-002-1248-4

3. Soccer-playing metal oxide giant spheres: a first step towards patterning structurally well defined nano-object collectives

Author:
Achim Müller; Ekkehard Diemann; S. Qaiser Nazir Shah; Christoph Kuhlmann; Matthias C. Letzel
Source:
Chemical communications 2002 v. no.5 pp. 440-441
ISSN:
1364-548X
Subject:
desorption; gases; ionization; mass spectrometry; molecular weight; molybdenum; sports
Abstract:
... In context with the challenge to assemble giant molecules into patterns with limited size, molybdenum oxide giant spheres (with a molecular mass of about 16 kDa) could be ‘kicked out’ like soccer balls into the gas phase using matrix assisted laser desorption and ionization (MALDI) and detected by TOF mass spectrometry while cluster collectives ranging from dimers to pentamers were observed. ...
DOI:
10.1039/b110917k

4. Gas-phase reactions for selective detection of the explosives TNT and RDX

Author:
Eduardo C. Meurer; Hao Chen; Leah Riter; Ismael Cotte-Rodriguez; Marcos N. Eberlin; R. Graham Cooks
Source:
Chemical communications 2003 v. no.1 pp. 40-41
ISSN:
1364-548X
Subject:
acetaldehyde; cycloaddition reactions; ethanol; explosives; gases; ionization; ions; tandem mass spectrometry; trinitrotoluene
Abstract:
... Highly selective gas-phase reactions with ethyl vinyl ether (EVE) of major electron (EI) and chemical ionization (CI) fragment ions of the explosives TNT and RDX have been uncovered. The fragment ion of m/z 210 from TNT undergoes [4⁺ + 2] cycloaddition with EVE to form an oxo-iminium ion of m/z 282, which dissociates by acetaldehyde loss after a [1,5-H] shift to form a quinolynium ion of m/z 238. ...
DOI:
10.1039/b309962h

5. Discrimination of three tobacco types (Burley, Virginia and Oriental) by pyrolysis single-photon ionisation–time-of-flight mass spectrometry and advanced statistical methods

Author:
T. Adam; T. Ferge; S. Mitschke; T. Streibel; R. R. Baker; R. Zimmermann
Source:
Analytical and bioanalytical chemistry 2005 v.381 no.2 pp. 487-499
ISSN:
1618-2642
Subject:
chemical composition; data collection; discriminant analysis; gases; ionization; ions; mass spectrometry; models; monitoring; nitrogen; principal component analysis; pyrolysis; smoke; tobacco
Abstract:
... Pyrolysis single-photon ionisation (SPI)–time-of-flight mass spectrometry (TOFMS) and statistical analysis techniques have been applied to differentiate three major tobacco types, Burley, Virginia and Oriental, by means of the gas phase. SPI is known as a soft ionisation technique that allows fast and comprehensive on-line monitoring of a large variety of aliphatic and aromatic substances without ...
DOI:
10.1007/s00216-004-2935-0

6. The 3D quadrupole ion trap mass spectrometer as a complete chemical laboratory for fundamental gas-phase studies of metal mediated chemistry

Author:
Richard A. J. O'Hair
Source:
Chemical communications 2006 v. no.14 pp. 1469-1481
ISSN:
1364-548X
Subject:
catalytic activity; chemical bonding; chemical compounds; dissociation; gases; ionization; ions; mass spectrometry; spectrometers
Abstract:
... Electrospray ionization provides a “treasure trove” of metal containing ions whose fundamental reactivity can be studied via collision induced dissociation and ion–molecule reactions using the multistage mass spectrometry capabilities of the quadrupole ion trap mass spectrometer. Examples of metal mediated chemistry relevant to catalysis, C–C bond coupling, bioinorganic and supramolecular chemistr ...
DOI:
10.1039/b516348j

7. Application of FT-ICR-MS for the study of proton-transfer reactions involving biomolecules

Author:
Raczyńska, E. D.; Gal, J.-F.; Maria, P.-C.; Zientara, K.; Szelag, M.
Source:
Analytical and bioanalytical chemistry 2007 v.389 no.5 pp. 1365-1380
ISSN:
1618-2642
Subject:
amino acids; bioactive properties; capillary electrophoresis; dissociation; gases; high performance liquid chromatography; ionization; mass spectrometry; nucleic acids; nucleosides; photolysis; polynucleotides; polypeptides; polysaccharides; proteins; zwitterions
Abstract:
... Fourier transform ion cyclotron resonance mass spectrometry, combined with modern ionization (fast atom bombardment , electrospray ionization, matrix-assisted laser desorption-ionization), fragmentation (collision-induced dissociation, surface-induced dissociation, one-photon ultraviolet photodissociation, infrared multiphoton dissociation, blackbody infrared radiative dissociation, electron-captu ...
DOI:
10.1007/s00216-007-1508-4

8. Assessment of metastable atom bombardment (MAB) ionization mass spectrometry for the fast determination of heterocyclic aromatic amines in cooked meat

Author:
Jamin, E.; Chevolleau, S.; Touzet, C.; Tulliez, J.; Debrauwer, L.
Source:
Analytical and bioanalytical chemistry 2007 v.387 no.8 pp. 2931-2941
ISSN:
1618-2642
Subject:
aromatic amines; chicken meat; cooked foods; cooking; gases; heat; heterocyclic amines; ionization; mass spectrometry; meat extracts; mutagenicity; nitrogen; pyrolysis; spectrometers
Abstract:
... An investigation of metastable atom bombardment (MAB) ionization mass spectrometry for the fast characterization of mutagenic/carcinogenic heterocyclic aromatic amines (HAAs) formed during heating processes of meats is presented. The aim of our study was to use the selective ionization of MAB to develop a detection method for HAAs in non-purified meat extracts, thus avoiding purification and conce ...
DOI:
10.1007/s00216-007-1170-x
PubMed:
17333148

9. ESI-MS analyses of lake dissolved organic matter in light of supramolecular assembly

Author:
Peuravuori, J.; Bursáková, P.; Pihlaja, K.
Source:
Analytical and bioanalytical chemistry 2007 v.389 no.5 pp. 1559-1568
ISSN:
1618-2642
Subject:
carbon; dissolved organic matter; electrospray ionization mass spectrometry; freshwater; gases; gel chromatography; ionization; ions; lakes; molecular weight; nitrogen; solutes; stable isotopes
Abstract:
... A high-performance size-exclusion chromatography (SEC) system was coupled on-line to an electrospray ionization (ESI) interface to detect gas-phase ions by an API 365 LC/MS/MS triple quadrupole analyzer. The SEC fractions of a strongly coloured freshwater solution containing dissolved organic matter-humic substances (DOM-HS) were screened both by UV₂₅₄ and by ESI mass spectrometry (ESI-MS) in the ...
DOI:
10.1007/s00216-007-1553-z
PubMed:
17899038

10. Enhancement of intensities in glow discharge mass spectrometry by using mixtures of argon and helium as plasma gases

Author:
Lange, Britta; Matschat, Ralf; Kipphardt, Heinrich
Source:
Analytical and bioanalytical chemistry 2007 v.389 no.7-8 pp. 2287-2296
ISSN:
1618-2642
Subject:
argon (noble gases); carbon; chlorine; copper; energy; fluorine; gases; helium; ionization; mass spectrometry; nitrogen; oxygen; phosphorus; sulfur
Abstract:
... Glow discharge mass spectrometry (GD-MS) is an excellent technique for fast multi-element analysis of pure metals. In addition to metallic impurities, non-metals also can be determined. However, the sensitivity for these elements can be limited due to their high first ionization potentials. Elements with a first ionization potential close to or higher than that of argon, which is commonly used as ...
DOI:
10.1007/s00216-007-1649-5

11. Laser-induced Fourier transform ion cyclotron resonance mass spectrometry of organic and inorganic compounds: methodologies and applications

Author:
Aubriet, Frédéric
Source:
Analytical and bioanalytical chemistry 2007 v.389 no.5 pp. 1381-1396
ISSN:
1618-2642
Subject:
biochemical compounds; energy; gases; inorganic compounds; ionization; ions; light intensity; mass spectrometry; organic compounds; photonics; spectrometers
Abstract:
... The combination of a laser with a Fourier transform ion cyclotron resonance mass spectrometer (FTICRMS) enables a variety of MS experiments to be conducted. The laser can be used either as an intense photonic source for the photoionization of neutral species introduced in a variety of ways into the FTICR cell, or it can be made to directly interact with a solid, generating gas-phase ions. Dependin ...
DOI:
10.1007/s00216-007-1491-9
PubMed:
17657480

12. Linear free energy relationships in C----N bond dissociations in molecular ions of 4-substituted N-(2-furylmethyl)anilines in the gas phase

Author:
Solano Espinoza, Eduardo A.; Stashenko, Elena; Martínez, Jairo; Mora, Uriel; Kouznetsov, Vladimir
Source:
Journal of mass spectrometry 2007 v.42 no.11 pp. 1496-1503
ISSN:
1076-5174
Subject:
dissociation; energy; enthalpy; gases; ionization; ions; mass spectrometry; spectral analysis
Abstract:
... The substituent effect on the reactivity of the C----N bond of molecular ions of 4-substituted N-(2-furylmethyl)anilines toward two dissociation pathways was studied. With this aim, six of these compounds were analyzed by mass spectrometry using electron ionization with energies between 7.8 and 69.9 eV. Also, the UB3LYP/6-31G (d,p) and UHF/6-31G (d, p) levels of theory were used to calculate the c ...
DOI:
10.1002/jms.1258

13. Top-down MS, a powerful complement to the high capabilities of proteolysis proteomics

Author:
McLafferty, Fred W.; Breuker, Kathrin; Jin, Mi; Han, Xuemei; Infusini, Giuseppe; Jiang, Honghai; Kong, Xianglei; Begley, Tadhg P.
Source:
FEBS journal 2007 v.274 no.24 pp. 6256-6268
ISSN:
1742-464X
Subject:
amino acid sequences; complement; digestion; dissociation; disulfide bonds; electrospray ionization mass spectrometry; electrostatic interactions; gases; hydrogen bonding; ionization; ions; isomers; peptides; post-translational modification; prediction; proteins; proteolysis; proteomics; spectrometers
Abstract:
... For the characterization of protein sequences and post-translational modifications by MS, the 'top-down' proteomics approach utilizes molecular and fragment ion mass data obtained by ionizing and dissociating a protein in the mass spectrometer. This requires more complex instrumentation and methodology than the far more widely used 'bottom-up' approach, which instead uses such data of peptides fro ...
DOI:
10.1111/j.1742-4658.2007.06147.x

14. 4-Chloro-α-cyanocinnamic acid is an advanced, rationally designed MALDI matrix

Author:
Jaskolla, Thorsten W.; Lehmann, Wolf-Dieter; Karas, Michael
Source:
Proceedings of the National Academy of Sciences of the United States of America 2008 v.105 no.34 pp. 12200-12205
ISSN:
0027-8424
Subject:
bovine serum albumin; gases; gels; ionization; ions; mass spectrometry; models; peptides; proteomics
Abstract:
... Matrix-assisted laser desorption ionization (MALDI) has become an enabling technology for the fields of protein mass spectrometry (MS) and proteomics. Despite its widespread use, for example, in protein identification via peptide mass fingerprinting, a comprehensive model for the generation of free gas-phase ions has not yet been developed. All matrices in use today, such as α-cyano-4-hydroxycinna ...
DOI:
10.1073/pnas.0803056105
PubMed:
18723668
PubMed Central:
PMC2527889

15. Can electrospray ionization help the characterization of iron gall inks? Investigation on the interactions of gallic acid with iron ions in aqueous solutions

Author:
Lutui, Marie-Anne; Gilard, Françoise; Sablier, Michel
Source:
Journal of mass spectrometry 2008 v.43 no.8 pp. 1123-1131
ISSN:
1076-5174
Subject:
aqueous solutions; dissociation; gallic acid; gases; ionization; ions; mass spectrometry; recipes; salts
Abstract:
... In the present work, an investigation has been conducted by electrospray ionization (ESI) experiments to characterize the structures of iron gall ink complexes in solution. Simple mono and polyphenolic acid molecules added to iron sulfate salts were chosen to model the recipes of ink composition. Theoretical calculations have been used (1) to determine the stability of the ionic complexes generate ...
DOI:
10.1002/jms.1396

16. Fragmentation of aromatic sulfonamides in electrospray ionization mass spectrometry: elimination of SO₂ via rearrangement

Author:
Sun, Mingjiang; Dai, Wenning; Liu, David Q.
Source:
Journal of mass spectrometry 2008 v.43 no.3 pp. 383-393
ISSN:
1076-5174
Subject:
aromatic compounds; atmospheric pressure; chlorine; dissociation; drugs; electrospray ionization mass spectrometry; extrusion; gases; ionization; ions; nitrogen; pharmacology; sulfonamides; sulfur; sulfur dioxide
Abstract:
... Arylsulfonamides are attractive pharmacophores for drug candidates. Fragmentation behaviors of selected aromatic sulfonamides were investigated using electrospray ionization mass spectrometry in the positive ion mode. Some of the sulfonamides afforded unique loss of 64 (loss of SO₂) ions upon collision-induced dissociation followed by intramolecular rearrangements in the gas phase. This SO₂ elimin ...
DOI:
10.1002/jms.1335

17. Gas-phase synthesis of the rare-gas carbene cation ArCH₂⁺ using doubly ionised bromomethane as a superelectrophilic reagent

Author:
Daniela Ascenzi; Paolo Tosi; Jana Roithová; Detlef Schröder
Source:
Chemical communications 2008 v. no.34 pp. 4055-4057
ISSN:
1364-548X
Subject:
argon (noble gases); carbenes; cations; gases; ionization
Abstract:
... The bimolecular reaction of mass-selected CH₃Br²⁺/CH₂BrH²⁺ dications with argon leads to the rare-gas carbene cation ArCH₂⁺, which represents an example of a new kind of organo rare-gas compound. ...
DOI:
10.1039/b811115d

18. Mass spectrometric study of the ionized C₆₀: (γ-Cyclodextrin)₂ inclusion complex by collision induced dissociation

Author:
Greisch, Jean-François; Kyritsoglou, Sam; Leyh, Bernard; De Pauw, Edwin
Source:
Journal of mass spectrometry 2008 v.43 no.2 pp. 242-250
ISSN:
1076-5174
Subject:
dissociation; electrons; fullerene; gamma-cyclodextrin; gases; ionization; ions; tandem mass spectrometry
Abstract:
... The water soluble inclusion complex [C₆₀:(γ-cyclodextrin)₂] has been characterized using electrospray tandem mass spectrometry and collision induced dissociation. [C₆₀:(γ-cyclodextrin)₂] ions were detected in the gas phase as doubly deprotonated, doubly protonated and doubly sodiated ions. The absence of monocharged complex ions following electronebulization is a likely consequence of the dimeric ...
DOI:
10.1002/jms.1296

19. Optimisation of a gas chromatographic method for trace gaseous impurities in nitrogen trifluoride by column sequence reversal

Author:
de Coning, Johannes Petrus; Swinley, John McNeil
Source:
Journal of chromatography 2008 v.1180 no.1-2 pp. 151-158
ISSN:
0021-9673
Subject:
carbon; carbon dioxide; carbon monoxide; detectors; equipment performance; gas chromatography; gases; helium; ionization; methane; nitrogen; nitrous oxide; oxygen; sulfur hexafluoride; system optimization
Abstract:
... Highly reactive fluorinated gaseous matrices require special equipment and techniques for the gas chromatographic analysis of trace impurities in these gases. The impurities that were analysed at the low mg/L levels included dioxygen (O₂), dinitrogen (N₂), carbon dioxide (CO₂), carbon monoxide (CO), sulfur hexafluoride (SF₆), methane (CH₄) and nitrous oxide (N₂O). Carbon tetrafluoride (CF₄) is als ...
DOI:
10.1016/j.chroma.2007.12.007

20. Protein structure and dynamics studied by mass spectrometry: H/D exchange, hydroxyl radical labeling, and related approaches

Author:
Konermann, Lars; Tong, Xin; Pan, Yan
Source:
Journal of mass spectrometry 2008 v.43 no.8 pp. 1021-1036
ISSN:
1076-5174
Subject:
additives; deuterium; electrospray ionization mass spectrometry; free radical scavengers; gases; hydroxyl radicals; ionization; ions; isotopes; monitoring; protein structure; proteins; solvents
Abstract:
... Mass spectrometry (MS) plays a central role in studies on protein structure and dynamics. This review highlights some of the recent developments in this area, with focus on applications involving the use of electrospray ionization (ESI) MS. Although this technique involves the transformation of analytes into highly nonphysiological species (desolvated gas-phase ions in the vacuum), ESI-MS can prov ...
DOI:
10.1002/jms.1435