摘要
空气中的水汽在远红外区(特别是400 cm-1以下)有强吸收,因此水汽峰的存在严重干扰远红外光谱的质量。该文利用湿度补偿原理除去水汽峰的干扰。在光谱采集过程中,观察水汽吸收带的大小和方向,在采集光谱的同时向光谱仪样品室通入干燥空气或潮湿空气来实时调节光谱仪样品室的相对湿度,使水汽的吸收峰随着扫描次数的增加而变小,最后获得无水汽吸收峰干扰的远红外光谱。实验结果表明,湿度补偿法可以彻底消除水汽吸收峰的干扰,并且具有快速和经济的特点。
Atmospheric water vapor exhibits strong spectral features in the far-IR region,particularly below 400 cm-1.Therefore,water vapor absorption bands may severely obscure important sample features in a far-IR spectrum.In this article,humidity compensation was applied to remove water vapor bands during the acquiring process of a far-IR spectrum.The scanning procedure of a single-beam sample spectrum was divided into two stages.At the first stage,the appearance of water vapor peaks is allowed and the absorption direction and intensity of water vapor bands can be observed easily at the end of this stage.Then,the relative humidity in the sample compartment of the spectrometer has to be changed by a dry or a wet air supply depending on the absorption direction of water vapor bands.For example,if the absorbance of water vapor is negative at the end of the first stage,then a wet air supply is necessary.After the relative humidity changes to a certain extent,water vapor peaks will become smaller and smaller with the increase in scanning number during the second stage.By this way,water vapor noise can be removed progressively and completely at last.
出处
《分析测试学报》
CAS
CSCD
北大核心
2012年第9期1142-1145,共4页
Journal of Instrumental Analysis
基金
国家自然科学基金资助项目(20873136)
关键词
远红外光谱
水汽干扰
湿度补偿
消除水汽谱带
far infrared spectrum
water vapor noise
humidity compensation
removing water vapor bands
