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Letter to the Editor I Mass-to-Charge Ratio Misassignments of Molecular Ions in Ion-Trap Mass Spectrometry To the Editor:

by unknown authors
"... Ion-trap mass pectrometers have been increasingly used for gas chromatography-mass spectrometry (GC-MS) analysis in analytical toxicology. Because the ion trap is operated in the mass-selective ejection m de (1), the stored ions have the opportunity to undergo a variety of ion-ion or ion-neutral int ..."
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Ion-trap mass pectrometers have been increasingly used for gas chromatography-mass spectrometry (GC-MS) analysis in analytical toxicology. Because the ion trap is operated in the mass-selective ejection m de (1), the stored ions have the opportunity to undergo a variety of ion-ion or ion

Galactic cosmic rays from supernova remnants. I. A cosmic-ray composition controlled by volatility and mass-to-charge ratio. Astrophys

by Jean-paul Meyer, Luke O’c. Drury, Donald C. Ellison - J , 1997
"... We show that the Galactic Cosmic Ray source (GCRS) composition is best described in terms of (i) a general enhancement of the refractory elements relative to the volatile ones, and (ii) among the volatile elements, an enhancement of the heavier elements relative to the lighter ones; this mass depend ..."
Abstract - Cited by 11 (1 self) - Add to MetaCart
dependence most likely reflects a mass-to-charge (A/Q) dependence of the acceleration efficiency; among the refractory elements, there is no such enhancement of heavier species, or only a much weaker one. We regard as coincidental the similarity between the GCRS composition and that of the solar corona

An approach to correlate tandem mass spectral data of peptides with amino acid sequences in a protein database

by Jimmy K. Eng, Ashley L. Mccormack, John R. Yates - J. Am. Soc. Mass Spectrom , 1994
"... A method to correlate the uninterpreted tandem mass spectra of peptides produced under low energy (lo-50 eV) collision conditions with amino acid sequences in the Genpept database has been developed. In this method the protein database is searched to identify linear amino acid sequences within a mas ..."
Abstract - Cited by 944 (19 self) - Add to MetaCart
mass tolerance of * 1 u of the precursor ion molecular weight. A cross-correlation function is then used to provide a measurement of similarity between the mass-to-charge ratios for the fragment ions predicted from amino acid sequences obtained from the database and the fragment ions observed

Summary

by unknown authors
"... LC, liquid chromatography; MS, mass spectrometry; MS/MS, tandem mass spectrometry; ESI, electrospray ionization; MALDI, matrix assisted laser desorption/ionization; CID, collision-induced disassociation; QTOF, quadrupole time-of-flight; RP, reversed phase; CV, coefficient of variation; zm / , mass-t ..."
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LC, liquid chromatography; MS, mass spectrometry; MS/MS, tandem mass spectrometry; ESI, electrospray ionization; MALDI, matrix assisted laser desorption/ionization; CID, collision-induced disassociation; QTOF, quadrupole time-of-flight; RP, reversed phase; CV, coefficient of variation; zm / , mass-to-charge

MASS SPECTROMETRY-BASED PROTEOMICS OVERVIEW

by unknown authors
"... Perhaps the most common and effective mass spectrometry-based protein sequencing methods have been those based on the bottom-up strategy (1–3). Here a protein or an entire proteome is enzymatically digested with trypsin (approximately 40 peptides/protein), chromatographi-cally separated, and interro ..."
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, and interrogated with tandem mass spectrometry [MS/MS; the process of ion fragmentation with subsequent mass-to-charge ratio (m/z) measurement]. Electrospray ionization (ESI) is the typical interface and is used to convert condensed phase ions

The Effect of the Argon Carrier Gas in the Multiphoton Dissociation-Ionization of Tetracene

by Juan Carlos Poveda, Ro San Román, Alfonso Guerrero, Ignacio Álvarez
"... Abstract: The multiphoton dissociation-ionization of tetracene at 355 nm using 6.5 nanosecond laser pulses, with and without argon as a carrier gas (CG), has been studied and compared. Ion fragments were analyzed in a time-of-flight mass spectrometer and separated according to their mass-to-charge r ..."
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Abstract: The multiphoton dissociation-ionization of tetracene at 355 nm using 6.5 nanosecond laser pulses, with and without argon as a carrier gas (CG), has been studied and compared. Ion fragments were analyzed in a time-of-flight mass spectrometer and separated according to their mass-to-charge

· ∆(m/q)

by S. A. Litvinov, A. Dolinskii, H. Geissel, Yu. A. Litvinov, H. Weick, Gsi Darmstadt
"... Exotic nuclei will be produced and separated in flight with the Super-FRS [1] at FAIR. The separated fragments will be injected and stored in the 13 Tm Collector Ring (CR) [2]. It will be used in the isochronous mode as a timeof-flight (TOF) spectrometer for short-lived exotic nuclides (T 1/2> 20 ..."
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; 20µs), a method which has been developed at the ESR [3]. The mass-to-charge ratio m/q of the stored ions circulating in the ring can be measured from the revolution frequency (f) and the velocity (υ) of the ions.

Statistics for Experimenters

by Gerald O. Hunter, Matthias Zeller, Brian D. Leskiw, Bruker Smart, Apex Ccd , 2005
"... R factor = 0.052; wR factor = 0.114; data-to-parameter ratio = 18.4. The title compound, [Zn(C8H10F3O2)2(CH4O)2], is a dimethanol coordinated zinc complex with the acetyl acetonate derivative 1,1,1-trifluoro-5,5-dimethylhexane-2,4dionate. The bis--diketonate complex, which is isostructural with its ..."
Abstract - Cited by 675 (1 self) - Add to MetaCart
R factor = 0.052; wR factor = 0.114; data-to-parameter ratio = 18.4. The title compound, [Zn(C8H10F3O2)2(CH4O)2], is a dimethanol coordinated zinc complex with the acetyl acetonate derivative 1,1,1-trifluoro-5,5-dimethylhexane-2,4dionate. The bis--diketonate complex, which is isostructural with its

Decimal place slope, a fast and precise method for quantifying 13C incorporation levels for detecting the metabolic activity of microbial species

by Nico Jehmlich, Ingo Fetzer, Jana Seifert, Jens Mattow, Carsten Vogt, Hauke Harms, Bernd Thiede, Hans-hermann Richnow, Martin Von Bergen, Frank Schmidt - Mol Cell Proteomics
"... *both authors contributed equally Abbreviations: 1-D – one dimensional, 2-DE – two-dimensional gel electrophoresis, CID-collision-induced dissociation, Da – Dalton, DNA – deoxyribonucleic acid, ESI- electrospray ionization, FT-ICR- fourier transform ion cyclotron resonance, HISH-SIMS- halogen in sit ..."
Abstract - Cited by 2 (0 self) - Add to MetaCart
in situ hybridization-secondary ion mass spectroscopy, HDPR- half decimal place rule, LC- liquid chromatography, LTQ- linear trap quadrupole, MALDI- matrix-assisted laser desorption/ionization, MS – mass spectrometry, m/z – mass-to-charge ratio, SIP – stable isotope probing, SDS-PAGE- sodium dodecyl

Ab Initio Prediction of Molecular Fragments from Tandem Mass Spectrometry Data

by Markus Heinonen A, Juha Kokkonen B, Juho Rousu A
"... Abstract: Mass spectrometry is one of the key enabling measurement technologies for systems biology, due to its ability to quantify molecules in small concentrations. Tandem mass spectrometers tackle the main shortcoming of mass spectrometry, the fact that molecules with an equal mass-to-charge rati ..."
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Abstract: Mass spectrometry is one of the key enabling measurement technologies for systems biology, due to its ability to quantify molecules in small concentrations. Tandem mass spectrometers tackle the main shortcoming of mass spectrometry, the fact that molecules with an equal mass-to-charge
Results 1 - 10 of 4,476