Laser microprobe mass spectrometry, for

Hgure 3 Scheme for molecular speciation of inorganic compounds using FT-LMMS. (Reprinted with permission from Struyf H, Van Vaeck L, Poels K, and Van Grieken R (1998) Fourier transform laser microprobe mass spectrometry for the molecular identification of inorganic compounds. Journal of the American Society for Mass Spectrometry 9 482-497 Elsevier.)... 

Figure 11 Identification of the interaction products between the triethanolamine oleate additive of a lubricating emulsion and rolled aluminum. Top positive ion mass spectrum recorded using FT-LMMS with an external ion source. Bottom structural assignment of the ions of major diagnostic interest. The corresponding high accuracy miz data are listed in Table 2. The framed structures are indicative of the binding of the additive to aluminum. (Reprinted from Poels K, Van Vaeck L, Van Espen P, Terryn H, and Adams F (1996) Feasibility of Fourier transform laser microprobe mass spectrometry for the analysis of lubricating emulsions on rolled aluminum. Rapid Communications in Mass Spectrometry W 1351-1360 Wiley.)...

Reprinted from Poels K, Van Vaeck L, Van Espen P, Terryn H, and Adams F (1996) Feasibility of Fourier transform laser microprobe mass spectrometry for the analysis of lubricating emulsions on rolled aluminum. Rapid Communications in Mass Spectrometry W 1351-1360 Wiley. 

Ignatova, V.A., Van Vaeck, L., Gijbels, R., Adams, F. (2002) Capabilities and limitations of Fourier transform laser microprobe mass spectrometry for molecular analysis of solids. Vacuum, 69,307-313. 

Infrared and ultraviolet probes for surface analysis are then considered.The applications of IR spectroscopy and Raman microscopy are discussed, and a brief account is also given of laser-microprobe mass spectrometry (LAMMA). 

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. 

Characterization thus involves analytical electron microscopy, ordinary microprobe analysis or other techniques for localizing elements or chemical compounds (Scanning Auger Spectroscopy, Raman Microprobe, Laser Microprobe Mass Spectrometry). It also requires, in most cases, some physical separation of the catalyst for separate analysis (e.g., near surface parts and center of pellets, by peeling or progressive abrasion pellets present at various heights in the catalyst bed, etc.). 

Optical microscopy (OM), polarized light microscopy (PLM), phase contrast microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and scanning transmission electron microscopy (STEM) are the methods normally used for identification and quantification of the trace amounts of asbestos fibers that are encountered in the environment and lung tissue. Energy-dispersive X-ray spectrometry (EDXS) is used in both SEM and TEM for chemical analysis of individual particles, while selected-area electron diffraction (SAED) pattern analysis in TEM can provide details of the cell unit of individual particles of mass down to 10 g. It helps to differentiate between antigorite and chrysotile. Secondary ion mass spectrometry, laser microprobe mass spectrometry (EMMS), electron probe X-ray microanalysis (EPXMA), and X-ray photoelectron spectroscopy (XPS) are also analytical techniques used for asbestos chemical characterization. 

The potential of laser microprobe mass spectrometry (LMMS) has been investigated for structural characterization of nucleosides and nucleotides. This technique is based on the measurement of ions formed promptly by direct desorption and ionization (DI) of solid microscopic samples. The DI process is very fast for nucleosides, which makes it possible to apply a relatively high laser energy to the sample. In the case of nucleosides, LMMS gives... 

Laser microprobe mass spectrometry (LMMS) confirms the existence of true interlayer complexes between cations and macrocyclic ligands (47). This technique, which provides mass spectra of fragmented solids after irradiation with a laser beam, was first used to characterize the intercalation compounds of crown ether- and cryptand-smectite complexes (47,48). One of the most interesting results derived from LMMS of these materials is the ability to corroborate the macrocycle-interlayer cation complexation, such as cryptand C(222)-Na-montmorillonite vs. Cu-montmorillonite. Alkaline-cryptand complexes are clearly assigned since the m/e values correspond to the sum of both the sodium and cryptand atomic mass (i.e., 399 Daltons for Na /C(222)). Transition metal... 

The main features of LMMS are summarised in Table 3.27. Laser microprobe mass spectrometry is a valuable tool for inorganic and oi anic analysis. Element location and quantification on the )u.m scale can be achieved (spot analysis) and speciation possibilities are available, which are unsurpassed by other... 

LMMS has also been used for direct analysis of normal-phase HPTLC plates (cfr. Chp. T.3.5.4 of ref. [13a]) and for identification of cloth samples by means of fingerprints from dyes and fabric softeners for forensic purposes [350], Applications of laser microprobe mass spectrometry were reviewed [53a, 328,334]. 

Mathey A, Van Roy W, Van Vaeek L, Eekhardt G, Steglich W (1994) In situ Analysis for a New Perylene Quinone in Lichens by Fourier-Transform Laser Microprobe Mass Spectrometry with External Source. Rapid Commun in Mass Spectrom 8 46... 

Van Vaeck L, Gijbels R and Lauwers W (1989) Laser microprobe mass spectrometry an alternative for structural characterisation of polar and thermolabile organic compounds. In Longidvalle P (ed) Advances in Mass Spectrometry, Vol. 11 A, pp. 348-349. London Heyden. 

Laser ionization mass spectrometry or laser microprobing (LIMS) is a microanalyt-ical technique used to rapidly characterize the elemental and, sometimes, molecular composition of materials. It is based on the ability of short high-power laser pulses (-10 ns) to produce ions from solids. The ions formed in these brief pulses are analyzed using a time-of-flight mass spectrometer. The quasi-simultaneous collection of all ion masses allows the survey analysis of unknown materials. The main applications of LIMS are in failure analysis, where chemical differences between a contaminated sample and a control need to be rapidly assessed. The ability to focus the laser beam to a diameter of approximately 1 mm permits the application of this technique to the characterization of small features, for example, in integrated circuits. The LIMS detection limits for many elements are close to 10 at/cm, which makes this technique considerably more sensitive than other survey microan-alytical techniques, such as Auger Electron Spectroscopy (AES) or Electron Probe Microanalysis (EPMA). Additionally, LIMS can be used to analyze insulating sam-... 

The technique is referred to by several acronyms including LAMMA (Laser Microprobe Mass Analysis), LIMA (Laser Ionisation Mass Analysis), and LIMS (Laser Ionisation Mass Spectrometry). It provides a sensitive elemental and/or molecular detection capability which can be used for materials such as semiconductor devices, integrated optical components, alloys, ceramic composites as well as biological materials. The unique microanalytical capabilities that the technique provides in comparison with SIMS, AES and EPMA are that it provides a rapid, sensitive, elemental survey microanalysis, that it is able to analyse electrically insulating materials and that it has the potential for providing molecular or chemical bonding information from the analytical volume. 

The technique based on laser-induced breakdown coupled to mass detection, which should thus be designated LIB-MS, is better known as laser plasma ionization mass spectrometry (LI-MS). The earliest uses of the laser-mass spectrometry couple were reported in the late 1960s. Early work included the vaporization of graphite and coal for classifying coals, elemental analyses in metals, isotope ratio measurements and pyrolysis [192]. Later work extended these methods to biological samples, the development of the laser microprobe mass spectrometer, the formation of molecular ions from non-voIatile organic salts and the many multi-photon techniques designed for (mainly) molecular analysis [192]. 

Lasers have been used in mass spectrometry for many years. Trace elements in biological samples [90] can be determined by using laser microprobes (LAMMA, laser microprobe mass analyzer) or a combination of laser ablation with ICPMS. For the analysis of bulk materials, techniques such as resonance ionization mass spectrometry (RIMS) and laser ablation MS (LAMS) are employed for a review see [91]. 

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