Quantitative measurements of broad-band mid-infrared absorption spectra of formaldehyde, acetaldehyde, and acetone at combustion-relevant temperatures near 5.7 µm

2020 ◽  
Vol 248 ◽  
pp. 106981
Author(s):  
Y. Ding ◽  
W.Y. Peng ◽  
C.L. Strand ◽  
R.K. Hanson
Keyword(s):  
Absorption Spectra ◽  
Infrared Absorption ◽  
Broad Band ◽  
Mid Infrared ◽  
Quantitative Measurements ◽  
Infrared Absorption Spectra

scholarly journals Optical and FT Infrared Absorption Spectra of 3d Transition Metal Ions Doped in NaF-CaF2-B2O3 Glass and Effects of Gamma Irradiation

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
F. H. A. Elbatal ◽  
M. A. Marzouk ◽  
Y. M. Hamdy ◽  
H. A. ElBatal
Keyword(s):  
Gamma Irradiation ◽  
Absorption Spectra ◽  
Infrared Absorption ◽  
Raw Materials ◽  
Broad Band ◽  
Transition Metal Ions ◽  
Nonbridging Oxygen ◽  
Hole Center ◽  
Doped Glasses ◽  
Infrared Absorption Spectra

Combined optical and FTIR spectroscopy has been employed to investigate the undoped NaF-CaF2-B2O3 glass together with samples containing 0.2% dopant of 3d TM ions before and after gamma irradiation. The optical spectrum of the undoped glass reveals strong UV absorption with two peaks which are related to unavoidable trace iron impurity within the raw materials. Upon gamma irradiation, an induced visible broad band centered at 500 nm is resolved and is related to B-O hole center or nonbridging oxygen hole center. TMs-doped samples exhibit characteristic absorption due to each respective TM ion but with faint colors. Gamma irradiation of TMs-doped samples reveals the same induced visible band at 500–510 nm in most samples except CuO and Cr2O3-doped glasses. Infrared absorption spectra reveal characteristic vibrational bands due to triangular and tetrahedral borate groups. The introduction of NaF and CaF2 modifies the borate network forming BO3F tetrahedra. The introduction of 3d TMs as dopants did not make any obvious changes in the FTIR spectra due to their low content (0.2%). Gamma irradiation causes only minor variations in the intensities of the characteristic IR borate bands while the bands at about 1640 cm−1 and 3450 cm−1 reveal distinct growth in most samples.

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