Introduction ferents with isotopes of analytical interest or that are incorporated into polyatomic interferences. 2 Evolution of LA-ICP-MS 3 Laser principles Motivated partly by such difficulties, alternative sample introduction methods such as direct sample insertion (DSI),4 3.1 Ruby 3.2 Nd5YAG electrothermal vaporization (ETV),5 spark ablation (SA)6 and laser ablation (LA)7 began to be used with ICP-MS. The 3.3 Excimer 4 Laser ablation systems ability of the ICP to accept vapours and solid aerosols produced by such methods for atomization and ionization was 5 Laser-solid interactions 6 Particle transport already known from optical emission spectrometry (OES). Indeed, development of these sample introduction techniques 7 Optimization 8 Calibration strategies for ICP-OES continues in parallel with their use in ICP-MS. Ablation of solids using pulses from a laser and carriage of 9 Performance and problems 10 Growth areas the released material to the ICP in a gas flow, usually of argon, is a very attractive alternative to the nebulization of 10.1 Fingerprinting 10.2 Geological microprobe analysis aqueous sample solutions. In addition to the usual analytical advantages of ICP-MS, LA offers reduced sample preparation, 10.3 Isotope ratios 11 Prospects rapid sample exchange and throughput, reduced spectral interferences and the possibility of in situ spatially resolved analysis. 12 References The key challenge in LA-ICP-MS, evident from the first feasibility study of the technique, which employed pulses from

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Molybdenum oxide thin films find diverse applications as catalysts, gas sensors, and electrochromic devices. Such films are produced mainly by reactive sputtering and thermal evaporation but other techniques such as chemical vapor deposition and electrochemical deposition have been used. In the present work, the feasibility of an alternative method for the production of molybdenum oxide films using a molybdenum filament heated in a rarefied oxygen atmosphere is demonstrated. The filament heating current, I F , and the oxygen flow rate, F O 2 , are the key deposition parameters and their effect on the deposition rate, R, was investigated. For I F ) 12.5 A, an increase in the R-value from 7.5 to 31 nm/min was observed as F O 2 was increased from 6.0 to 21 sccm. To characterize the chemical bonds, infrared spectroscopy, using both unpolarized and p-polarized infrared beams, and X-ray photoelectron spectroscopy (XPS) were employed. Line shape analysis of the Mo(3d) XPS peak revealed that the Mo atoms were in mixed valence states, Mo 6+ and Mo 5+ , with a high predominance of the former over the latter, thus indicating an oxygen-deficient MoO 3 film. From Rutherford backscattering spectroscopic analysis of the films, an average O/Mo atomic ratio of 2.9 was calculated, consistent with the XPS results. A combination of the XPS and RBS results and the data of other investigators on the oxidation of molybdenum suggests that the film is formed from MoO 2 and MoO 3 species desorbed from the Mo filament. The optical gap, E g , was determined from transmission UV-visible spectra of the films. An average E g value of 3.03 eV was found. The electrochromic properties of the films were investigated for Li + intercalation using an electrochemical cell. A coloration efficiency of 19.5 cm 2 /C at a wavelength of 700 nm was observed.

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