Tunable Diode Laser Absorption Spectroscopy (TDLAS) is a non-intrusive method of measurement, which has lots of advantages, such as real-time, fast response, high sensitivity, easy operation, harsh condition applicability and so on. In this paper, the 7173.781201 and 7199.37761 cm-1 line pair of water vapor were selected for the temperature measurement of the flat flame burner. In order to observe the non-uniform temperature distribution, the Fourier-Hankel transform in the inverse Abel transform was used to convert the integrated temperature, which got by TDLAS, into temperature field.
The full color greenish-white-emitting phosphors Eu 2+ -doped Sr 3 Bi(PO 4 ) 3 have been successfully synthesized by the conventional solid-state reaction, and its photoluminescence properties have been investigated for the first time. The emission spectra of Sr 3 Bi(PO 4 ) 3 ∶Eu 2+ phosphors exhibit a greenish-white-emitting by combining blue, green, and red emissions, which are originated from the 5d→4f transition of the Eu 2+ . The excitation spectra reveal broad strong bands from 300 to 400 nm, which match well with the readily available emissions from near-ultraviolet light-emitting diode (LED) chips. The correlated color temperature, color rendering index (CRI), and Commission Internationale de I’Eclairage chromaticity coordinates of the entitled phosphors excited by 330 and 365 nm are also investigated. The experimental results indicate that the Eu 2+ -doped Sr 3 Bi(PO 4 ) 3 phosphors are a promising innovative greenish-white-emitting phosphor for white LEDs.
Wavelength modulation spectroscopy has not yet formed an efficient method applied to measure line shape, which has restricted the development of tunable diode laser absorption spectroscopy. In the present paper, we have established a method which can recover line shape directly by using the data of the X and Y axes of odd harmonics based on the absorption spectral and harmonic theories. And then, in validating the accuracy of this method, the numerical simulation was used to recover the line shape of the transition at 6527.641cm-1. Meanwhile, the experimental results show that the method established in this paper can recover the line shape accurately.