Title Page
초록
ABSTRACT
Contents
1. INTRODUCTION 18
1.1. Research Background 18
1.2. Chemical warfare agents 21
1.2.1. Nerve agents 21
1.2.2. Blister Agents 25
1.2.3. Blood agents 26
1.2.4. Choking agents 27
1.3. CWA simulants 28
1.4. Toxic industrial chemicals 30
1.5. Gas detection technologies 32
1.5.1. Surface Acoustic wave 32
1.5.2. Infrared spectroscopy 34
1.5.3. Raman spectroscopy 35
2. DETECTION TECHNOLOGIES OF CWAs 36
2.1. Surface Acoustic Wave (SAW) sensor 36
2.1.1. Piezoelectric materials 38
2.1.2. Interdigital transducer 39
2.1.3. Detection mechanism 41
2.2. Quantum cascade laser 43
2.2.1. IR spectrometry 45
2.2.2. Beer-Lambert law 46
3. EXPERIMENTS 47
3.1. Design of gas generating system 47
3.1.1. Bubbler based gas generator 47
3.1.2. Syringe based gas generator 49
3.2. SAW gas sensor 52
3.2.1. Design of SAW sensor 52
3.2.2. 4-channels array sensor 55
3.2.3. Sensing receptors 58
3.2.4. Experimental setup 60
3.3. QCL based gas detector 62
3.3.1. Configuration of QCL gas detector 62
3.3.2. Experimental setup 64
4. EXPERIMENTAL RESULTS 66
4.1. SAW sensor 66
4.1.1. Detection to GA 66
4.1.2. Detection to GB 68
4.2. QCL based gas detector 71
4.2.1. Gas concentration analysis 71
4.2.2. Chemical gas detection 76
5. CONCLUSIONS 81
REFERENCES 84
OUTCOMES OF RESEARCH 92
Table 1-1. Nerve agents 22
Table 1-2. Blister agents 25
Table 1-3. Blood agents 26
Table 1-4. Choking agents 27
Table 1-5. The simualnts of chemical warfare agents 28
Table 1-6. Hazard index parameter 30
Table 1-7. Classifications of TIC by hazard levels 31
Table 2-1. Properties of piezoelectric materials 38
Table 2-2. Properties of IDT electrode metal 40
Table 3-1. Design parameter of the SAW sensor 53
Table 3-2. Liquid injection (ύ=5L/min) for generating gases and temperature of gas heater 65
Table 4-1. Physical properties of toxic materials tested 74
Figure 1-1. Representative chemical incidents in modern society: (a) Tokyo subway sarin terror, (b) Sulfur mustard poisoning symptom in Iraq-Iran War, (c) Chest X-rays of a patient... 20
Figure 1-2. Nerve agents' effects on the body 23
Figure 1-3. Attack mechanism of the nerve agent 24
Figure 1-4. Configuration of the surface acoustic wave sensor 33
Figure 1-5. Infrared spectrometry 34
Figure 1-6. Schematic showing energy transition of Rayleigh and Raman scattering 35
Figure 2-1. SAW sensor design 37
Figure 2-2. Schematic of SAW structure 39
Figure 2-3. Schematic diagram of the SAW sensor detection 42
Figure 2-4. Electronic energy band structure of the gain superlattice: (a) under zero-applied electrical field, (b) under an applied electric field sufficiently large to form a Wannier-Stark... 44
Figure 3-1. Bubbler type gas generator 48
Figure 3-2. 3D modeling of the syringe-based gas generator 50
Figure 3-3. Photolithography process 53
Figure 3-4. SAW sensor: (a) top, (b) side, (c) optical microscope image 54
Figure 3-5. Frequency response of manufactured SAW sensor 54
Figure 3-6. Signal processing diagram 56
Figure 3-7. SAW array device with a portable battery 56
Figure 3-8. Circuit diagram of SAW oscillator 57
Figure 3-9. Sensing materials for detecting nerve agents: (a) POSS based polymer with 4-(Trifluoromethyl) phenol and PSS-Octakis (dimethylsilyloxy), (b) TU based polymer... 58
Figure 3-10. Drop casting process 59
Figure 3-11. Experimental setup for SAW array device (a) Exposure condition to nerve agents, and (b) Cleaning process. 61
Figure 3-12. Schematic of the QCL based detector 63
Figure 3-13. Experiment set up for evaluating the QCL based gas detector 65
Figure 4-1. Sensitivity of SAW array device to GA: (a) SAW sensor coated with POSS, (b) SAW sensor coated with TU-1, and (c) SAW sensor coated with TU-2 67
Figure 4-2. Sensitivity of SAW array device to GB: (a) SAW sensor coated with POSS, (b) SAW sensor coated with TU-1, and (c) SAW sensor coated with TU-2 69
Figure 4-3. Comparison of SAW sensor's performance under GB exposure condition 70
Figure 4-4. Gas chromatography analysis of toxic gas generated self-made equipment (a)DMMP, (b)CEES, (c)Methanol, and (d)Ethanol 74
Figure 4-5. Comparison of GC analysis result by toxic materials 75
Figure 4-6. Gas detection performance of QCL based detector under exposure to various toxic gases (a)DMMP, (b)CEES, (c)DEP, (d)Ethanol, (e)Methanol, and (f)Ammonia 78
Figure 4-7. Gas detection performance of QCL based detector under exposure to chemical warfare agents (a)Tabun (GA), (b)Sarin (GB), (c)Soman (GD), and (d)Sulfur mustard (HD). 80