Resolution mapping —

A multiresidue analytical method based on sohd-phase extraction enrichment combined with ce has been reported to isolate, recover, and quantitate three sulfonylurea herbicides (chlorsulfuron, chlorimuron, and metasulfuron) from soil samples (105). Optimi2ation for ce separation was achieved using an overlapping resolution map scheme. The recovery of each herbicide was >80% and the limit of detection was 10 ppb (see Soil chemistry of pesticides). 

However, the spatial resolution of AES is mueh greater than that of XPS and ean approaeh approximately 25 nm. This makes AES a powerful technique for constructing high-resolution maps showing the distribution of chemical species across a surface. Because of the small analysis area, it is an easy matter to combine AES with inert gas sputtering to construct depth profiles showing the distribution of chemical species as a function of distance away from the surface and into the bulk of the solid. Quantitative analysis can be done using sensitivity factors and an equation similar to Eq. 17. 

The silicon map shows the distribution of slag inclusions, while the position of the weld lines can be seen to be marked by boundaries between areas of high and low phosphorus content and by enrichments of nickel and/or arsenic at the weld lines. Higher resolution maps can be made of welds to reveal their fine structure. 

An example of a higher resolution map from the EPMA is given in Figure 5.11, where the sample is again an archaeological specimen - a pair of shears from the same site as the specimen shown in Figure 5.10. Here the weld lines are marked by lines of sulphide and slag particles in an area depleted of phosphorus. 

Love, J.M., Knight, A.M., McAleer, M.A. and Todd, J.A. (1990) Towards construction of a high resolution map of the mouse genome using PCR-analysed microsatellites. Nucleic Acids Research 18, 4123 1130. 

Ng et al. [107] described a simple and rapid systematic optimization scheme, known as overlapping resolution mapping scheme, which make use of nine... 

FIGURE 5 Optimization of gradient time (to) resolution map and chromatogram. 

Kassabov, S.R., Henry, N.M., Zofall, M., Tsukiyama, T., and Bartholomew, B. (2002) High-resolution mapping of changes in histone-DNA contacts of nucleosomes remodeled by ISW2. Mol. Cell. Biol. 22, 7524-7534. 

Among the many microscopy-based techniques for the study of biomolecular interactions on surfaces, scanning probe microscopies, and especially the atomic force microscopies (AFM), are the most used because of their molecular and sub-molecular level resolution and in situ imaging capability. Apart from the high resolution mapping of siuface nanotopographies, AFM can be used for the quantification and visualisation of the distribution of chemistry, hydrophobicity and local mechanical properties on surfaces, and for the fabrication of nanostructmes on surfaces. 

In a high-resolution mapping of the cardiac activation in isolated rabbit hearts, the stochastic nature of propagation mentioned above may be reflected by the beat-to-beat variability observed by others [Dhein et al., 1990]. 

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