Graphite diode lasers

Ng K. C., Ali A. H., Barber T. E. and Winefordner J. D. (1988) Multiple mode semiconductor diode laser as a spectral line source for graphite furnace atomic absorption spectroscopy, Anal Chem 62 1893-1895. 

Zybin A., Schurer-Patschan C. and Niemax K. (1992) Simultaneous multi-element analysis in a commercial graphite furnace by diode laser induced fluorescence, Spectrochim Acta, Part B 47 1519-1524. 

Wizemann HD and Niemax K (2000) Measurement of Li-7/Li-6 isotope ratios by resonant Doppler-free two-photon diode laser atomic absorption spectroscopy in a low-pressure graphite furnace. Spectrochimica Acta B 55 637-650. 

Laser desorption atmospheric pressure chemical ionization (LD-APCI) combines a laser system and an APCI source to desorb and ionize small chemical compounds on TLC plates (Figure 7.3) [29]. Vaporization and desorption of analytes from the TLC gel bed was achieved by surface heating with a continuous wave (CW) diode laser operated at 808 nm. It was reported that a laser power density of 10 W/cm enables desorption of analytes from white TLC plates. Furthermore, the application of a graphite suspension (10 mg/mL in isopropanol) on the TLC gel decreased the CW laser power required for analyte desorption to 10" W/cm. Thermally desorbed analytes were postionized by reacting with charged species generated by corona discharge of the air. The TLC LD-APCI/MS approach was first used to characterize... 

P. Ljung, O. Axner Measurements of rubidium in standard reference samples by wavelength-modulation diode laser absorption spectrometry in a graphite furnace. Spectrochim. Acta B 52, 305 (1997)... 

Raman spectra were recorded using a Spex Triplemate spectrograph equipped with a diode array detector. The 514 nm line of an Ar+ laser was used for excitation. The Raman spectra displayed a band at approximately 1600 cm-1 due to C-C vibrations of graphite-like structures and a band at 1365 cm 1 due to imperfections of the graphite lattice and to amorphous carbon. The width of the 1600 cm"1 band in the Raman spectra has been reported to be inversely proportional to the degree of graphitization [5,6]. 

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