표제지
목차
요약 13
1. 서론 15
2. 실험방법 18
2.1. 토양 시료 준비 18
2.2. 논토양을 이용한 microcosm 실험 20
2.3. 2-line ferrihydrite의 합성 22
2.4. 2-line ferrihydrite에 대한 각 비소 화학종 별 등온흡착실험 22
2.5. 물벼룩(Daphnia magna)를 이용한 급성독성실험 23
2.6. HPLC-ICPMS를 이용한 Methylated thioarsenicals 분석방법 25
3. 결과 및 토의 26
3.1. 논토양을 이용한 microcosm 실험 26
3.1.1. ORP, pH 및 DOC 농도 변화 26
3.1.2. total As 및 As species 농도 변화 34
3.2. 2-line ferrihydrite 합성 결과 44
3.3. 2-line ferrihydrite에 대한 각 비소 화학종 별 등온흡착실험결과 45
3.4. D. magna에 대한 급성독성실험 결과 52
4. 결론 54
5. 참고문헌 56
Abstract 65
Table 1. Result of analysis of physicochemical properties of paddy soil 19
Table 2. Analysis conditions of inductively coupled plasma mass spectrometer (ICPMS) and high performance liquid chromatography (HPLC). 25
Table 3. Brunauer-Emmett-Teller (BET) analysis result of synthesized 2-line ferrihydrite. 45
Table 4. Maximum sorption capacity (qm) and coefficient of determination (R²) for arsenicals obtained by Langmuir isotherm equation fitting[이미지참조] 46
Table 5. 24 h and 48 h EC50 of each arsenic species for D. magna obtained by acute toxicity test. 53
Fig. 1. Paddy soil sampling 18
Fig. 2. Paddy soil microcosm setup. For pore water collection between experiments, a hole of 1 cm in diameter was made... 21
Fig. 3. Changes in reduction-oxidation potential between microcosm experiments (reduction period 20 days, oxidation period... 28
Fig. 4. Changes in reduction-oxidation potential for each control and experimental group between microcosm experiments... 29
Fig. 5. Changes in pH between microcosm experiments (reduction period 20 days, oxidation period 28 days). The black line indicates... 30
Fig. 6. Changes in pH for each control and experimental group between microcosm experiments (reduction period 20 days).... 31
Fig. 7. Changes in DOC concentrations between microcosm experiments (reduction period 20 days, oxidation period 28 days).... 32
Fig. 8. Changes in DOC concentrations for each control and experimental group between microcosm experiments (reduction... 33
Fig. 9. Changes in total As concentrations between microcosm experiments (reduction period 20 days, oxidation period 28 days).... 36
Fig. 10. Results of arsenic species analysis for each control group and experimental group between microcosm experiments 37
Fig. 11. Changes in total Fe concentrations between microcosm experiments (reduction period 20 days, oxidation period 28 days).... 38
Fig. 12. Changes in total Fe concentrations for each control and experimental group between microcosm experiments (reduction... 39
Fig. 13. Changes in sulfate concentrations between microcosm experiments (reduction period 20 days, oxidation period 28 days).... 40
Fig. 14. Changes in sulfate concentrations for each control and experimental group between microcosm experiments (reduction... 41
Fig. 15. Changes in sulfide concentrations between microcosm experiments (reduction period 20 days, oxidation period 28 days).... 42
Fig. 16. Changes in sulfide concentrations for each control and experimental group between microcosm experiments (reduction... 43
Fig. 17. X-ray diffraction (XRD) analysis result of synthesized 2-line ferrihydrite 44
Fig. 18. Particle size analysis results of synthesized 2-line ferrihydrite 45
Fig. 19. Sorption isotherm at different pH values (4, 7, and 10) for As(V) on 2-line ferrihydrite. qe is the concentration (mg/g) of... 47
Fig. 20. Sorption isotherm at different pH values (4, 7, and 10) for DMA on 2-line ferrihydrite. qe is the concentration (mg/g) of DMA... 48
Fig. 21. Sorption isotherm at different pH values (4, 7, and 10) for DMMTA on 2-line ferrihydrite. qe is the concentration (mg/g) of... 49
Fig. 22. Sorption isotherm at different pH values (4, 7, and 10) for DMDTA on 2-line ferrihydrite. qe is the concentration (mg/g) of... 50