Fluorescence spectrometry steady state

The application of semiconductor lasers to a broad range of areas in spectrometry has recently been reviewed by Imasaka. 67, 68) Topics covered include photoacoustic, absorption, and thermal lens, as well as steady-state and time-resolved fluorescence. Patonay et al. have reviewed the application of diode lasers to analytical chemistry.(69) The performance of several commercially available laser diodes for fluorimetry has recently been compared. 70 ... 

Patton, W. F. (2004). Gharacterization of dynamic and steady-state protein phosphorylation using a fluorescent phosphoprotein gel stain and mass spectrometry. Electrophoresis 15, 2526-2532. 

The theory of rotation effects on prolate luminescent molecules in solution and its experimental verification have been developed and compared. Generalized diffusion equations for the rotational motion of an asymmetric rigid motor have been used to given an expression for steady-state fluorescence depolarization. " The radiationless transition from the first excited singlet state of Eosin has been measured by optoacoustic relaxation, and the absolute fluorescence quantum yields of organic dyes in poly(vinyl alcohol) have also been measured by the photoacoustic method. The accuracy of the method has been discussed in the latter paper. Actinometry in flash photolysis experiments has been assisted by new measurements on the extinction coefficient of triplet benzophenone. Matrix-isolation fluorescence spectrometry has been used to detect polycyclic aromatic hydrocarbons from gas chromatography. ... 

Most importantly, however, photoexcitation methods allow the detection of transient species. While an entity with a lifetime of 50 ns or less can be comfortably analyzed by transient absoiption or fluorescence spectrometry, other physical methods of steady-state character are likely to fail. For example, the timescale of most NMR experiments is longer than ca. 100 ms. which renders this method unsuitable for studies of short-lived species. 

X-ray Fluorescence Spectrometry and Inductively Coupled Plasma analysis reveal the presence in the zircons of all existing REE. The steady-state luminescence in natural zircons is dominated by broad emission arising from radiation-induced centers and narrow emission lines of Dy " (Trofimov 1962 Tarashchan 1978). These emissions obscure the spectra of other REE. The thermal treatment enables to solve this problem in certain cases using the fact that the intensity of broad band luminescence quickly decreases after heating at 700 °C-800 °C, while the intensities of the REE lines remain nearly constant (Shinno 1986, 1987). Even after heating the samples not all the REE can be identified by steady-state spectroscopy since the weaker luminescence lines of certain REE are obscured by stronger luminescence of others. For example, luminescence of Pr " is difficult to... 

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