摘要
在常规的傅里叶变换红外光谱（ＦＴＩＲ）学中，干涉图的直流成分为∫∞０Ｂ（σ）ｄσ，而在时间分辨ＦＴＩＲ中，直流成分Ｉｄｃ（τ）成为∫∞０Ｂ（σ，τ）ｄσ，即与信号出现的时间τ有关，称为定时直流成分。Ｉｄｃ（τ）具有随红外信号强度Ｂ（σ）成正比以及不可被滤除等性质。Ｉｄｃ（τ）经傅氏变换后在光谱中出现定时零频信号Ｂτ（０）。Ｉｄｃ和Ｂτ（０）可用来多方面监测实验条件如气压、激光强度和窗口碳化的变化，以及可用于测量仪器的响应时间和带通频率。
The direct current component in the interferogram of conventional FTIR spectroscopy is expressed by ∫ ∞ 0 B(σ) d σ.However,in time resolved FTIR spectroscopy,the direct current component I dc (τ) also depends upon τ,the time which IR signal appears.I dc (τ) is then represented by ∫ ∞ 0 B(σ,τ) d σ,called as constant in time DC component by us.I dc (τ) is proportional to the signal intensity B(σ).I dc (τ) can not be filtered by any band pass filter.After Fourier transforming,the I dc (τ) converts to a strong peak at 0cm -1 in the IR spectrum.We call it as constant in time zero frequency signal B τ(0).Either I dc or B τ(0) can be used to monitor a variety of experimental conditions,such as the variation of gas pressure,laser intensity,the carbon deposition on the optics,etc.They can also be applied to measure the instrumental response time and the band pass frequency.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
1998年第2期152-157,共6页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金
关键词
时间分辨
FTIR
干涉谱
直流成分
Time resolved FTIR spectroscopy, Interferogram, Direct current component
