Fourier transform mass spectrometry FT-MS

These developments [together with the availability of high-performance instruments, e.g., Fourier transform-mass spectrometry (FT-MS) and Orbitrap] make possible the application of MS in many different fields. The problem is to individualize the best instrumental choices and the related parameterization to obtain the analytically more valid results, which allows to propose new, highly specific analytical methods. 

The product phosphonomandelylThDP (PMThDP) formed on BFDC from MBP and ThDP was also confirmed (Fourier-transform mass spectrometry (FT-MS)) in solution,and of PLThDP (from MAP. ThDP) by X-ray methods on Elec and on POX. The X-ray structures of the PMThDP adduct on BAL... 

Results of Fourier-transform mass spectrometry (FT-MS) studies with the carbon oxides 3-5 conclusively demonstrate that one reaction pathway to the formation of fullerenes is the coalescence of large cyclocarbon ions [21, 23], In the negative-ion mass spectra of the carbon oxides, the expected successive losses of CO molecules from the precursor anions to give the cyclocarbon ions Cii, and were observed. In the positive-ion mode, gas-phase coalescence reactions of the cyclocarbon ions produced fullerene ions. Ion-molecule reactions starting from the cyclocarbon cations Cl s (formed by laser desorption of 3), and 2 (formed from 4) led through distinct intermediates Cjg -... 

Aaserud et al. reported an on-line coupling of SEC to Fourier transform mass spectrometry (FT-MS) using a modified commercial electron spray ionization (ESI) interface (Fig. 29) [169]. They analyzed a glycidyl methacrylate/butyl methacrylate copolymer with a broad molecular weight distribution, where fractionation and high resolving power were required for adequate characterization. The SEC/ESI/FT-MS also allowed for an unequivocal end-group determination and characterization of a secondary distribution due to the formation of cyclic reaction products. 

LC-TOF MS offers fuU-scan high sensitivity, high mass accuracy close to that provided by high-resolution Fourier-transform mass spectrometry (FT-MS) instruments (orbitrap and FT-ICR-MS). 

The term 1 or h indicates low or high coverage of adsorbed ethene, as inferred from ethene exposures.h TPD, temperature-programmed desorption LITD, laser-induced thermal desorption 1 FT-MS, Fourier-transform mass spectrometry SIMS, secondary-ion mass spectrometry MS, mass spectrometry T-NEXAFS, transient near-edge X-ray absorption fine structure spectroscopy RAIRS, reflection-absorption infrared spectroscopy. d Data for perdeut-erio species.1 Estimated value. 

Technological advances of ion-trap mass spectrometers are the ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and the recently released technique, the Orbitrap Fourier transform mass spectrometry (Hu et al., 2005), which enable the determination of molecular formulae with a high mass resolution and mass accuracy in mixtures. Today these ion-trap mass spectrometers are most frequently coupled with atmospheric pressure ionization (API) techniques such as electrospray ionization (ESI) (e.g., Fievre et al., 1997 Qian et al., 2001 Kujawinski et al., 2002 Llewelyn et al., 2002 Stenson et al., 2002,2003 Fard et al., 2003) or matrix-assisted laser desorption/ionization (MALDI) (e.g., Solouki et al.,... 

The first step is the priming of the NRPS active site and a subsequent limited tryptic digest of the protein. The digested sample is loaded on a reverse-phase liquid chromatography (RPLC) C18 column, which is directly connected to the inlet of an FT mass spectrometer. During online LC separation, the eluent is analyzed by MS and MS2 on an LC timescale. In the mass spectrometer the eluent is first analyzed by broadband Fourier transform mass spectrometry (FTMS). Then, peaks in the resulting broadband FT mass spectrum are... 

Fast Atom Bombardment-Fourier Transform-Mass Spectrometry (FAB-FT-MS) and low-energy collisional activation experiments proved that the oligomers of j3-ketolactone generally have a macrocyclic ring structure rather than a catenane ring. ... 

NMR) [24], and Fourier transform-infrared (FT-IR) spectroscopy [25] are commonly applied methods. Analysis using mass spectrometric (MS) techniques has been achieved with gas chromatography-mass spectrometry (GC-MS), with chemical ionisation (Cl) often more informative than conventional electron impact (El) ionisation [26]. For the qualitative and quantitative characterisation of silicone polyether copolymers in particular, SEC, NMR, and FT-IR have also been demonstrated as useful and informative methods [22] and the application of high-temperature GC and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) is also described [5]. 

Today the population is becoming increasingly exposed to ultrafine particles (< 20 nm, e.g., Aerosil, 2) in bodycare and household products. Ion microscopy studies revealed that such particles can, for example, penetrate the horny layer of the skin and can result in unexpected interactions. SIMS and Fourier transform laser microprobe mass spectrometry (FT LMMS) have been applied to study 2 stimulated interaction in thin layers of dermatological gels as a result of UV irradiation.175 For future studies of distribution of ultrafine particles LA-ICP-MS will be employed. 

MS, Mass spectrometry El, electron impact Cl, chemical ionization MID, multiple ion detection PICI, positive-ion chemical ionization NICI, negative-ion chemical ionization SIM, selected ion nmonitoring TSP, thermospray PPINICI, pulsed positive ion-negative ion chemical ionization ECD, electron-capture detector NPD, nitrogen/phosphorous detector NSTD, nitrogen-selective thermionic detector FT-IR, Fourier transform infrared spectrometry. 

Attempts have been made to observe and experimentally determine the structure of CH5+ in the gas phase and study it in the condensed state using IR spectroscopy,764 765 pulse electron-beam mass spectrometry,766 and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS).767 However, an unambiguous structure determination was unsuccessful. Retardation of the degenerate rearrangement was achieved by trapping the ion in clusters with H2, CH4, Ar, or N2. 

Kujawinski, E. B., Hatcher, P. G., and Freitas, M. A. (2002). High-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) of humic and fulvic acids Improvements and comparisons. Anal. Chem. 74,413 119. 

The quadrupole ion trap is seen as a compact and less expensive alternative to FT-ICR mass spectrometers employed for gas-phase metal ion chemical and mass analysis [28,29]. Although lacking the high mass resolving powers available in Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), the quadrupole ion trap has been investigated by using nonselective and resonance-selective ionization of ablated metal samples. 

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