Researches On Application Of Artificial Nose And Artificial Tougue In Environment Dectecting

With the rapid increase of economy and the excessive exploitation of resources, The problems of pollution more and more are focused by people's eyes.Among the problems, toxic and harmful organic gases and heavy metals distributing comprehensively various waters which are severely endangering human health are more paid attention to by society. It is urgent to detect toxic and harmful organic gas and heavy metals on-line and rapidly.At the same time, with the development of technology of artificial olfactory, artificial taste and chemical sensor, the research about artificial nose and artificial tongue is on the way to be a focus in the world and are applied in the detection of gas and ion in the liquid .The research about gas sensors and heavy metal sensors and real-time detection and analyse techniques are also foreland topics to research in the world. For the reasons above-mentioned, the researches on optical artificial nose based on the optical fibre sensors and artificial tongue based on the heavy metal ion selective sensors are as major tasks in the thesis and financed by Nation 863 High-tech Project Fund, China-Russia Special Fund in International Cooperation at Nation Nature Science Fund (NSFC) and Key Project of Department of Science and Technology in Zhejiang Province.The major contents of this thesis are given in the following aspects:1. A kind of laboratorial system of artificial optical nose with the characteristic of bionics is introduced Utilizing the design metheod of bionics of biologic olfactory and the characteristic of optic fiber sensor about easily to combine with lots of sensitive polymer to achieve many quantificational confections of sensitive polymers and fluorescent reagents, and develop the optic fiber sensor array with different selectivities.Besides,an olfactory mechanism was adopted to the artificial nose, which can differentiate the component and concentration information of mixed gases from the responsive signal data of the optic fiber sensor array adopting OSN-OB-DLNN (olfactory sensory neuron-olfactory bulb-delay line neural network)arithmetic by simulating biological olfaction.2. Based on light-addressable potentiometric sensor (LAPS) and pulsed laser deposition (PLD) technique, a kind of cadmium (â…¡) ion selective thin film sensor with glass state structure has been developed for the first time. The chalcogenide material of a kind of ion selective electrode (Cd—ISE) sensitive to cadmium (â…¡) ion used as a target of PLD device, correspondingly thin film sensor (Cd—LAPS) with glass state structure sensitive to cadmium (â…¡) ion was prepared on the surface of LAPS. The Cd—LAPS has a good linearity range of 10^-4～10^-7mol/L, the limit of determination 1.15×10^-7 mol/L, suitable pH range 4 to 7.The calibration curve has good repetitiveness in 2 weeks.3. Based on LAPS and PLD technique, a kind of copper (â…¡) ion selective thin film sensor with glass state structure has been developed for the first time. The chalcogenide material of a kind of ion selective electrode (Cu—ISE) sensitive to copper (â…¡) ion used as a target of PLD device, correspondingly thin film sensor (Cu—LAPS) with glass state structure sensitive to copper (â…¡) ion was prepared on the surface of. LAPS. The Cu—LAPS has a good linearity range of 10^-4～10^-6 mol/L, the limit of determination 5.44×10^-7 mol/L, suitable pH range 4 to 7.The calibration curve has good repetitiveness in 1 weeks.4. Combine the technology of micro-lens array and the LAPS thin film sensors, two types of LAPS array sensors are developed which can realize the differentiation and dection of Cu²⁺,Cr⁶⁺,pb²⁺,Fe³⁺ and Cr⁶⁺,pb²⁺,Fe³⁺ respectively.5. The existing form of Hg in the solution system is discussed and the free Hg²⁺ with stable and low concentration and the relationship between the free Hg²⁺ and the total Hg in the solution. After the calibration to the buffer solution whose composition is like the seawater with the Hg ion selective electrode (Hg-ISE), it seems that the relationship between the concentration of total Hg and the concentration of free Hg²⁺ is approximately linear when the concentration of the free Hg²⁺ is higher than 10^-19mol/L.In the same way, the characteristic of Zn-ISE in the buffer system is studied and it seems that the detection limit of Zn-ISE is higher than 10^-8 mol/L.6. A automatic analysis experimental device of artificial tongue is preprared based on membrane electrode,LAPS and ISE technique for the determination of heavy metals,which is used in the detection in water environment.It seems that the device can satify need of the detection of water environment from the data of experiment.7. The development prospect of gas sensor, heavy metal sensor and the analysis system are viewed .The application prospect of the optical fiber network monitoring harmful gases and flow injection analysis, capillary electrophoresis, microelectro- mechanical system (MEMS) and micro total analysis system (or microfluidic chip systems) monitoring heavy metal ions on-line are pointed out.