Scanning application

Optical microactuators like a micromirror for scanning applications have been proposed by Orsier et al. (1996). A two-dimensional bimorph (Si 4- magnetostrictive film) is driven remotely by two differently oriented magnetic fields working at different frequencies in order to obtain the bending and torsional vibrations due to the magnetostrictive strain. 

In addition to the continuum sources just discussed, line sources are also important for use in the UV/visible region. Low-pressure mercury arc lamps are very common sources that are used in liquid chromatography detectors. The dominant line emitted by these sources is the 253.7-nm Hg line. Hollow-cathode lamps are also common line sources that are specifically used for atomic absorption spectroscopy, as discussed in Chapter 28. Lasers (see Feature 25-1) have also been used in molecular and atomic spectroscopy, both for single-wavelength and for scanning applications. Tunable dye lasers can be scanned over wavelength ranges of several hundred nanometers when more than one dye is used. 

The problem in slow scan applications is often to synchronise the recording process in the TCSPC device with the scanner. Attempts to control both the scanning and the TCSPC recording per software usually fail because of undefined processing times in a multitask operating system. 

The metal-channel design of the R5600 and R7400 results in slight periodical variations of the efficiency and the IRF over the active area, see Fig. 6.41. Consequently, either the entire active area should be illuminated or the position of the illuminated spot should be kept stable. Variations in the position can be a pitfall in TCSPC scanning applications (see Fig. 5.93, page 158). 

The next step is evaluation in the error of chromatography. Standard tracks (after development) are integrated, and the error in chromatography determined from the calculated variance, which is the sum of the variances of scanning, application, and chromatography ... 

UV-visible spectra were determined using a Varian Cary 100 Bio-UV-Visible split-beam spectrophotometer running with Cary WinUV scan application with a capacity of measuring six samples at a time. Samples were scanned at 500 nm. A high-intensity Xe flash lamp was used as the source for UV light, which permits taking 80 data per second. 

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