EDXRS Experimental Study For The Application Of Detecting Illegal And Heavv Metal

In this dissertation, the feasibility of energy dispersive X-ray scattering (EDXRS) method for security detection of drugs which hidden inside and outside the human body was studied under simulating in complex backgrounds, and extended the technique applied to detection and recognition of water heavy metal and liquid precursor chemicals. The main contents and conclusions are summarized as follows:1. Implementing EDXRS technique and coupling with the appropriate analysis algorithm provide specific material identification. Profile analysis of herion has been performed using the Coherence Function. The Results suggest that it is feasible to recognize heroin covered by simulation skin through coherence function analysis method. Meanwhile, the coherence coefficient can also be made as criterion of characteristic signal recognization. Thus, heroin in the body can be identified automatically.2. The Energy Dispersive X-ray Diffraction (EDXRS) is one of the most detection techniques used in inspecting. By means of this measurement, the energy dispersive diffraction profiles at different scattering angles of methamphetamine, heroin, simulated human body, methamphetamine concealed in simulated human body and heroin concealed in simulated human body had been investigated respectively in order to accurately and rapidly confirm methamphetamine and heroin concealed in simulated human body. Combine EDXRS with similarity theory were used to analysis the detection data of EDXRS. On the one hand, the norm and calculation method of similarity between drug standard profile and test profile were proposed. On the other hand, method of deduction background was proposed and be used to analysis the drugs covered by simulated skin. The results shown the data analysis method can be used to analyze test data and to accurately identify methamphetamine concealed in simulated human body and heroin concealed in simulated human body.3. Cadmium, mercury, arsenic and lead in the water were detected analysis using energy dispersive X-ray scattering experiment platform. Heavy metal elements of the solution can be qualitatived analysis according to the fluorescence peak position of the EDXRS spectra. The results shown that energy dispersive X-ray scattering experiment platform can be used to identification high concentration heavy metal of aqueous solution. Furthermore, the method of detection and identification of low concentration heavy metal of aqueous solution is put forword by the energy dispersive X-ray scattering testing technology.4. The common nine liquid precursor substances including formaldehyde, sulfuric acid, pyridine, chloroform, hydrogen peroxide, ether and hydrochloric acid and acetyl acetone) and distilled water were detected using the EDXRS liquid detection platform device. The spectra of energy dispersive X-ray scattering were obtained. The results shown that the peak shape, the maximal peak position and the peak scattering intensity of each liquid precursor substances EDXRS spectral are different at the same detection conditions. The peak shapes and the maximal peak position of the EDXRS spectra can be considered as the main features of information for liquids identification, and the scattering intensity of the EDXRS spectra was the assistant features of identification information. Liquid precursor chemicals characteristics can be classified and identified combine with computer algorithm identification research (PCA). Therefore, EDXRS might become a kind of non destructive non-contact rapid detection and identification of liquid precursor material of a kind of effective method.