Microanalysis Applications

LIMS is primarily used in failure microanalysis applications, which make use of its survey capability, and its high sensitivity toward essentially all elements in the periodic table. The ability to provide organic molecular information on a microanalyt-ical scale is another distinctive feature of LIMS, one that is likely to become more important in the future, with improved knowledge of laser desorption and ionization mechanisms. 

L. E. Murr, Electron and Ion Microscopy and Microanalysis Principles and Applications, 2nd ed.. Optical Engineering Vol. 29, Dekker, New York, 1991. 

J. I. Goldstein, Dale E. Newbury, P. Echlin, D. C. Joy, C. Fiori, and E. Lif-shin. Scanning Microscopy and X-Ray Microanalysis. Plenum Press, New York, 1981. An excellent and widely ranging introductory textbook on scanning microscopy and related techniques. Some biological applications are also discussed. 

The STEM is unrivaled in its ability to obtain high-resolution imaging combined with microanalysis from specimens that can be fashioned from almost any solid. Major applications include the analysis of metals, ceramics, electronic devices... 

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-... 

Relatively little has been reported regarding the determination of the purity of the halide salts other than by standard spectroscopic measurements and microanalysis. This is largely because the halide salts are rarely used as solvents themselves, but are generally simply a source of the desired cation. Also, the only impurities likely to be present in any significant quantity are unreacted starting materials and residual reaction solvents. Thus, for most applications it is sufficient to ensure that they are free of these by use of FF NMR spectroscopy. 

The application of surface analytical techniques, most notably X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES), or its spatially resolved counterpart. Scanning Auger Microanalysis (SAM), is of great value in understanding the performance of a catalyst. However, the results obtained from any of these techniques are often difficult to interpret, especially when only one technique is used by itself. 

Specific Application Petrogenic Modelling Based on Microanalysis... 

Miller, M.K. Smith, G.D.W. (1989) Atom Probe Microanalysis Principles and Applications to Materials Problems, Materials Research Society, Pittsburgh, PA, USA. 

We have not included Atom Probe Microanalysis in this scheme. It constitutes the ultimate in local analysis - in that individual atoms can be selected and identified by TOF spectroscopy. Chapter 1 gives an account of the range of applications of the technique at the present time the development in atom-probe methods has allowed the continuing increase of both the volume of material that can be mapped at the atomic scale and the quality of the data obtained. 

G. Chiavari, D. Fabbri, S. Prati, R. Mazeo, D. Bikiaris, S. Daniilia and Y. Chrussoulakis, Analytical pyrolysis application to the characterisation of Byzantine painting layers, Proceedings of 6th International Conference on Non Destructive Testing and Microanalysis for the Diagnostics and Conservation of the Cultural and Environmental Heritage (Eds M. Marabelli and C. Parisi), Euroma, Rome, 1999, pp. 1145 1162. 

Furthermore, under controlled bombardment conditions, peak intensity measurements may be used for a quantitative determination of the appropriate element. Measurements of the characteristics and intensity of primary X-rays produced by electron bombardment constitute the basis of electron probe microanalysis. Figure 8.33 illustrates the complex nature of the reactions initiated by the impact of an electron beam on a target. As a consequence of this complexity it has proved extraordinarily difficult to make fully quantitative measurements, and it is only recently with the widespread application of dedicated computers and sophisticated software that this has become possible. 

Sigee DC. X-ray Microanalysis in Biology Experimental Techniques and Applications, Cambridge University Press, Cambridge, UK, 1993. 

With some exceptions (2-4), there have been relatively few recent reviews of microanalysis that have considered applications to plant science. In a previous review of this topic (5), I concentrated almost entirely on methods of specimen preparation for electron probe X-ray microanalysis. Here I highlight further developments in this area, and also broaden the scope of the review to include other microanalytical techniques. This chapter introduces the main types of hardware that are now available for microanalysis, reviews the main techniques used to prepare plant material prior to analysis, and provides protocols for the two major techniques. 

Harvey DMR. Applications of x-ray microanalysis in botanical research. Scanning Electron Microsc 1986 HI 953-973. 

Z.G. Li, Applications of microscopy in Organic Light-Emitting Diode Research and Development, Proc. Microscopy and Microanalysis, 1352-1353, 2004. 

Electron and Ion Microscopy and Microanalysis Principles and Applications, Lawrence E. Murr... 

Local thickness variations in a thin specimen complicate the quantitative analysis of a single element in the absence of precise knowledge of specimen thickness and without the ability to compare the measured x-ray intensities with those of thin standards. To avoid this difficulty, the x-ray intensity for the element of interest can be divided either by the intensity of a region of background between peaks as in the Hall method[8], or by the intensity from another element as in the Cliff-Lorimer method[9]. The former is largely used for biological analysis while the latter has become the standard thin specimen microanalysis method for materials science applications. The Cliff-Lorimer method is expressed in the following equation ... 

Synchrotron applications in archaeology date back to 1986 (Harbottle et al. 1986), and have been subsequently documented on a dedicated website at Daresbury [http //www.srs.ac.uk/srs/]. The majority of the early applications use SR as a source for X-ray fluorescence microanalysis on a variety of materials, including glass (Schofield et al. 1995, Janssens et al. 1996), ink and paper (Mommsen et al. 1996), dental calculus (Capasso et al. 1995), and bone (Janssens et al. 1998b). The repertoire has been expanded to include X-ray... 

Owing to the small size of the electron beam on the one hand, and to the high sensitivity of the method on the other (a sensitivity which can go down to detection of 10 16g), electron-probe microanalysis has found applications in many fields. 

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