Applications laser ablation

Barefoot, R.R. Determination of platinum group elements and gold in geological materials a review of recent magnetic sector and laser ablation applications. Anal. Chim. Acta 509, 119-125 (2004)... 

Laser Ablation Applicable to a wide family of materials fast and computer controlled possibility to incorporate bioactive molecules no toxic solvent no high temperature control on pore size and orientation control on scaffold porosity Resolution depending on the spot diameter frnpossible to produce complex structures with overhangs or interior geometry... 

Y is monitored as it can be aspirated during laser ablation applications where a small bleed is useful for tuning and centring purposes. 

Laser based mass spectrometric methods, such as laser ionization (LIMS) and laser ablation in combination with inductively coupled plasma mass spectrometry (LA-ICP-MS) are powerful analytical techniques for survey analysis of solid substances. To realize the analytical performances methods for the direct trace analysis of synthetic and natural crystals modification of a traditional analytical technique was necessary and suitable standard reference materials (SRM) were required. Recent developments allowed extending the range of analytical applications of LIMS and LA-ICP-MS will be presented and discussed. For example ... 

Initial results prove the high potential of LA-based hyphenated techniques for depth profiling of coatings and multilayer samples. These techniques can be used as complementary methods to other surface-analysis techniques. Probably the most reasonable application of laser ablation for depth profiling would be the range from a few tens of nanometers to a few tens of microns, a range which is difficult to analyze by other techniques, e. g. SIMS, SNMS,TXRE, GD-OES-MS, etc. The lateral and depth resolution of LA can both be improved by use of femtosecond lasers. 

Laser ablation of polymer films has been extensively investigated, both for application to their surface modification and thin-film deposition and for elucidation of the mechanism [15]. Dopant-induced laser ablation of polymer films has also been investigated [16]. In this technique ablation is induced by excitation not of the target polymer film itself but of a small amount of the photosensitizer doped in the polymer film. When dye molecules are doped site-selectively into the nanoscale microdomain structures of diblock copolymer films, dopant-induced laser ablation is expected to create a change in the morphology of nanoscale structures on the polymer surface. 

Wang, Z., Masuo, S., Machida, S. and Itaya, A. (2005) Application of dopant-induced laser ablation to site-selective modification of sea-island structures of polystyrene-fclock-poly(4-vinylpyridine) films. Jpn. J. Appl. Phys., 44, L402-L404. 

The increasing application of laser ablation or induced techniques for local and bulk analysis, whereby either the sampled vapor or the excited light becomes trans-... 

Horn I, Rudnick RL, McDonongh WF (2000) Precise elemental and isotope ratio determination by simultaneous solution nebnlization and laser ablation-ICP-MS Application to U-Pb geochronology. ChemGeol 164 281-301... 

There are a few drawbacks to this method. Using 4 or 5 TIMS measurements to produce a U-series date profile across a bone is time consuming, although a single reliable U-series date is surely worth hundreds where the accuracy is not known. In future, the application of Laser-Ablation ICP-MS to measuring profiles will significantly reduce the analytical effort required to obtain a date. 

The application of the Diffusion-Adsorption model to dating bone (by AP) was funded by a NERC grant to Robert Hedges at the Research Laboratory for Archaeology, University of Oxford. The U-series date profiles shown here were measured at the NERC U-series dating facility at Open University, and the laser ablation U-series profile was measured at the Research School for Earth Sciences, Australian National University, Canberra in collaboration with Steve Eggins and Rainer Griin. 

Prochazka M., Mojzes P., Stepanek J., Vlckova B., Turpin P.Y., Probing applications of laser ablated Ag colloids in SERS spectroscopy Improvement of ablation procedure and SERS spectral testing, Anal. Chem. 1997 69 5103-5108. 

Despite the frequent use of arc-discharge and laser ablation techniques, both of these two methods suffer from some drawbacks. The first is that both methods involve evaporating the carbon source, which makes it difficult to scale up production to the industrial level using these approaches. Second, vaporization methods grow CNTs in highly tangled forms, mixed with unwanted forms of carbon and/or metal species. The CNTs thus produced are difficult to purify, manipulate, and assemble for building nanotube-device architectures in practical applications. 

Photo/Thermal Reactions. The fifth basic class of photopolymer chemistry that can be used in commercial applications is based more on physical changes in a polymer-based matrix than on chemical reactions. A recent application of this technology is the laser ablation (77) of an organic coating on a flat support to directly produce a printing plate. The availability of newer high energy lasers will allow more applications to be based on the photo/thermal mechanism. 

For the majority of applications, the sample is taken into solution and introduced into the plasma as an aerosol in the argon stream. The sample solution is pumped by a peristaltic pump at a fixed rate and converted into an aerosol by a nebulizer (see atomic absorption spectrometry). Various designs of nebulizer are in use, each having strengths and weaknesses. The reader is directed to the more specialist texts for a detailed consideration of nebulizers. There is an obvious attraction in being able to handle a solid directly, and sample volatilization methods using electric spark ablation, laser ablation and electrothermal volatilization have also been developed. 

A particular advantage of ICP-MS derives from its ability to display a complete mass spectrum at one time. Combined with sample introduction by laser ablation it constitutes a very powerful tool for first-look analysis, e g. in geological prospecting or ecological surveys. ICP-MS is applicable to the whole range of areas where minor or trace elements are to be determined. 

Laser ablation has become a prominent analytical technique over the past decade with applications crossing into many scientific disciplines, including geoscience, environmental, and forensics, among others (Baudelet, et al. 2007 ... 

In most applications of ICP-AES, the sample is introduced as a liquid (although solid samples can be dealt with using laser ablation, discussed in Section 9.1 in the context of ICP MS). Usually a small pump sucks up the... 

Inductively coupled plasma mass spectrometry is now such an important technique in archaeology, as elsewhere, that we devote a whole chapter to it. There are now a number of different ICP MS modes of operation (solution analysis, laser ablation, multicollector, high resolution) this chapter provides a general overview. Further description of the instrumentation for ICP MS may be found in Harris (1997) and Montaser (1998). Some general applications of solution ICP MS are discussed by Date and Gray (1989), Platzner (1997), and Kennett et al. (2001). 

Evans, R. D. and Outridge, P. M. (1994). Applications of laser ablation inductively coupled plasma mass spectrometry to the determination of environmental contaminants in calcified biological structures. Journal of Analytical Atomic Spectroscopy 9 985-989. 

Gratuze, B. (1999). Obsidian characterization by laser ablation ICP-MS and its application to prehistoric trade in the Mediterranean and the Near East sources and distribution of obsidian within the Aegean and Anatolia. Journal of Archaeological Science 26 869-881. 

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