Transient-digitizer technique

IFast- transient digitizing ZBoxcar integration 3. Delayed coincidence 

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Transient-Digitizer Technique. The most direct way of capturing the transient signal from the photomultiplier tube is to use a normal fast oscilloscope and take a photograph of the screen with open camera shutter while the electron beam, whicli is trigged by the laser, sweej j the screen drawing the decay curve. Clearly, it is inconvenient to further process data... 

Examples of atomic excited-state decay curves recorded with the transient digitizer technique for a sequence of states in sulphur are shown in Fig. 9.20. The lifetimes increase with a r oc trend as expected for a Rydberg sequence... 

Fig. 9.20. Time-resolved laser-induced fluorescence recordings in a sequence of sulphur, employing the transient digitizer technique [9.122]...

The final point of comparison between the two techniques concerns the time required to record the data. A decent time resolution on the signal requires data to be taken at perhaps 100 time points following photolysis, and this is done in a facile manner by use of a transient digitizer, as described for... 

There has been a considerable decline in the number of papers which deal with the details of techniques of measurement of fluorescence decay. This is no doubt due to the fact that the alternative methods are now essentially well established. Nevertheless a microcomputerized ultrahigh speed transient digitizer and luminescence lifeline instrument has been described . A very useful multiplexed array fluorometer allows simultaneous fluorescence decay at different emission wavelength using single photon timing array detection . Data collection rates could approach that for a repetitive laser pulse system and the technique could be usefully applied to HPLC or microscopy. The power of this equipment has been exemplified by studies on aminotetraphenylporphyrins at emission wavelengths up to 680 nm. The use and performance of the delta function convolution method for the estimation of fluorescence decay parameters has been... 

Britz, D., Digital Simulation in Electrochemistry, Springer-Verlag, Berlin, 1981 and MacDonald, D., Transient Techniques in Electrochemistry, Plenum Press, New York, 1977. Both of these books contain copious details concerning electrochemical simulations. Although these texts are extremely mathematical (as all simulation work has to be), the basic concepts are not too difficult to follow. The application notes to Condecon (see URL on page 301) are also a feast of detail. 

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