Showing papers in "International Journal of Mass Spectrometry and Ion Processes in 1992"

TL;DR: In the last few years negative thermal ionization IDMS has become a frequently used method as discussed by the authors, and it has been shown to be one of the most powerful analytical methods for speciation in the future.

TL;DR: The 351 nm photoelectron spectra of the phenide, benzyl and phenoxide anions are reported in this paper. But the results are limited to the presence of two vibrational modes at 600(10) and 968(15) cm −1, and an excited electronic state at ⩽ 1.7 eV.

TL;DR: In this paper, a thermal ionisation mass spectrometer was used to obtain absolute values for the iron isotope abundance ratios of a sample of metallic iron of natural isotopic composition.

TL;DR: In this paper, the isomerization is viewed in terms of a "proton transport" mechanism in which a "foreign" molecule transports the proton from a high energy site to a low energy site of a protonated molecule.

TL;DR: Reflection time-of-flight mass spectrometry in combination with laser ionization is described in this article, with special emphasis on the spatial focus of an ion source and on reflection techniques for correction of these time-ofthe-flight uncertainties.

TL;DR: A review of the literature on charge-remote fragmentation can be found in this article, where the authors focus on both expanding the scope of charge remote fragmentation and applying it to real problems.

TL;DR: In this paper, a dual cubic trap was used to store benzene molecular ions for several seconds at high pressure (> 1 x 10−5 mbar) in one half of a dual trap, as demonstrated by subsequent transfer of these ions to the other half for ICR excitation and detection.

TL;DR: The surface-induced dissociation (SID) as discussed by the authors showed that the fluorinated surface is a particularly hard surface, being effective at transferring projectile translational energy into internal energy.

TL;DR: The gas phase acidities of 19 α amino acids have been determined using the kinetic method of Cooks and co-workers [R.G. Cooks, J.L. Kruger, S.A. McLuckey, D. Cameron and R.G.

TL;DR: In this paper, the authors describe several new ion sources for FT-ICR MS (e.g., high pressure, fast neutral beam, and continuous flow atom bombardment), various new ion traps employing screens, and guard wires for improved isotopic abundance accuracy.

TL;DR: In this paper, a set of electron impact ionization cross-section data for O2 for electron impact energies from threshold to 1000 eV was generated using a crossed electron beam-molecular beam collision geometry and the relative flow technique measurements.

TL;DR: In this article, the Fourier transform ion cyclotron resonance mass spectrometry is evaluated in trapped ion cells which substitute open rectangular trapping electrodes for trapping plates positioned perpendicular to the magnetic field.

TL;DR: In this paper, a tandem mass spectrometer of EBEEBE geometry (B = magnetic sector; E = electric sector), designed for fundamental studies of gaseous ions and neutral reactive molecules, is described.

TL;DR: Analytical pyrolysis mass spectrometry (PYMS) is introduced and its applications to the analysis of synthetic polymers, biopolymers, biomacromolecular systems and geomacromoles are critically reviewed.

TL;DR: In this article, the authors used thermal ionization mass spectrometers for isotopic analysis of neodymium, samarium, gadolinium and lutetium.

TL;DR: The current status of PSMS is reviewed in this paper, with an emphasis on current capabilities and shortcomings, and a sampling of recent activities in the field is then documented, including modifications of conventional plasma ion sources, introduction of new plasmas for PSMS, and the use of alternative mass spectrometers for elemental analysis.

TL;DR: In this article, a commercially available secondary ion mass spectrometer equipped with an auxiliary high voltage electron flood gun and modified to allow the detection of secondary ions sputtered with initial kinetic energies up to 4500eV.

TL;DR: In this article, a procedure for the determination of chlorine isotopic ratios by positive thermal ionization mass spectrometry of the Cs2Cl+ ion has been investigated and optimal conditions for measurement have been established.

TL;DR: In this article, a correction function (extraction efficiency vs. fragment kinetic energy) is claculated for a given potential distribution of a Nier-type ion source extraction system, which is applied to previously measured partial ionization cross-sections of CF4.

TL;DR: In this paper, the yields of multiply charged ions produced from photoabsorption of Ne, Ar, Kr and Xe over the photon energy range 44-1300 eV have been measured using a time-of-flight mass spectrometer and monochromatized synchrotron radiation.

TL;DR: In this paper, a linear correlation was found between the proton affinities and the adiabatic nitrogen lone pair ionization energies for those amino acids which protonate on the amine group, even in cases where the nitrogen lone pairs is not the highest occupied molecular orbital.

TL;DR: In this article, the progress made during the past three years in all aspects of ion trap mass spectrometry is reviewed and a review of axial modulation, mass-selective axial ion ejection, ion isolation, collision-induced dissociation, and dynamically programmed scans is reviewed.

TL;DR: In this article, the dependence of H/D exchange on the pressure of ND3, on collision energy and on proton affinities (PAs) of the peptides is examined.

TL;DR: In this paper, a critical evaluation of existing energetic data for N 2 H + 3, CH 5 N + 2 and C 2 H 7 N + ions, and collision experiments on deuterium labelled species, was concluded that several reported appearance energy (AE) measurements on hydrazines are probably in error owing to interferences from traces of amines.

TL;DR: In this paper, one measure of the capacity of an ion mobility spectrometer (IMS) to distinguish between signals and relates the maximum theoretical discrimination to that obtained in real systems is described.

TL;DR: The tyrothricin peptide complex, isolated from the fermentation broth of Bacillus brevis, is comprised of a basic fraction of cyclic decapeptides and a neutral fraction composed of linear peptides (the gramicidins).

TL;DR: In this paper, a simulation of ion motion in a quadrupole ion trap is described, and a numerical solution to the Mathieu differential equation is obtained based on the Taylor series method.

TL;DR: Some of the models that have been proposed to account for ion formation during sputtering are reviewed in this article, with particular attention paid to models describing polyatomic ion formation, and some of the characteristics that a suitable model would possess are identified from the experimental data.

TL;DR: In this article, a trisector EBE mass spectrometer is modified to accommodate neutralization-reionization (NRMS) experiments and collisionally-activated dissociation (CAD) processes.

TL;DR: In this paper, the use of three commercial double-focussing mass spectrometers for double-charge transfer spectrometry is described, and the results are compared with those obtained by other experimental techniques and with data and state assignments from theoretical studies.