Research On Short NIR Spectroscopy Applying To Flammable Liquid Detection

Now the safety problem is becoming more and more important along with the unceasing change of international circumstance. At present widespread application the safety detection devices are based on the imaging theory of X-ray to obtain the information of people's parcels. To the combustible and explosive liquid, for example the ethanol, gasoline, petroleum, methyl alcohol and so on, visible and the smell examination method often be used in the inspection. So the application of new methods to detect liquid dangerous goods is the pop problem of this field. The near-infrared spectral analysis technology has the merit of high sensitivity, quick speed of response and so on,so it's suitable in in Situ and online analysis, In this paper,we reaserch the method of detect liquid on Short NIR Spectroscopy in Situ.This article uses the transmission analysis technology, spectroscope has conducted the background influence research of vessel on USB2000. The survey wave from 350nm-1000nm, we attempt to discover the appropriate wavelength in this wave band.First each kind of vessel primitive transmission spectrogram has been surveyed, and the absorbency of each vessil with taking air as the background, then carried on the comparison to the measurement result, and determined the appropriate research wave band (739nm-1000nm).And measured the absorbency of water with taking the vessel as the background and taking the air as background, validate that the vessel could not affect the absorbency of liquid in choosen wave band.We has measuired the absorbency of common flammable liquid such as absolute ethyl alcohol, absolute methanol, ammonia water, turpentine, gasoline, diesel oil, petroleum and the partial white liquors, the drink in short near-infrared (667-1000nm)in the infrared spectroscope absorption pectrum of Brucker Optics Company. Using the smooth method of Savitzky-Golay to carry on to the primitive absorption spectrum to remove the high frequency noise of the signal disturbance, the baseline adjustment deducte instrument background or the drifting to the influence of the signal, and so on normalization to the data. We mainly carries on the qualitative analysis to the data, therefore we can use the software of SPSS to carry on the distinction analysis to seek the characteristic point wave-length. the characteristic wave-length of the absorption spectrum was analyzed using the SPSS statistics software. A math model for flammable liquid distinction was established based on the designated characteristic wave-length and it can correctly detect flammable liquid using the absorbency of 3 wave-lengths (981nm,935nm, 881nm). The results indicated that, it is feasible to apply the short wave near-infrared spectroscopy in flammable liquid detection.Take this, we can use inexpensive spectrum installment whose photosource may make use of semiconductor laser (LD) or light emitter diode (LED) as the with these 3 wave-length to check the flammable liquid, for enhances the accuracy and the efficiency of security check.