13. 50 ml reaction flasks (for manual ammonium analysis).
14. 25 ml reaction flasks with screw caps (e.g., Pyrex containers for
manual nitrate analysis).
15. 50 ml graduated cylinders.
16. 100–1000 ml volumetric flasks.
17. 100–1000 ml storage bottles.
18. Spatulas.
19. Adjustable pipettes and pipette tips.
20. Analytical balance.
21. Oven capable of being maintained at 45
C.
22. Refrigerator.
23. 1 cm quartz glass cuvette or flow through cuvette (for manual
nitrate analysis).
24. 5 cm quartz glass cuvette (for manual ammonium analysis).
25. Spectrophotometer or automatic analyzer.
2.2 Dissolved
Organic Nitrogen
(Total Dissolved
Nitrogen)
1. 24 ml glass autosampler vials with screw caps.
2. Oven (450
C).
3. Concentrated hydrochloric acid (37% HCl).
4. Ultrapure water (e.g., Milli-Q).
5. 0.7 μm glass fiber filters (25 mm Ø) and Swinnex filter holders.
6. Disposable 20 ml sterile syringes.
7. Ammonium sulfate (NH 4 SO 4 ).
8. Spatulas.
9. Analytical balance.
10. 100–1000 ml volumetric flasks.
11. Adjustable pipettes, pipette tips.
12. Ultrasonicator bath.
13. Plastic film (e.g., Parafilm).
14. Refrigerator and freezer.
15. CN analyzer with autosampler and instrument specific carrier
gas and oxidizing agents.
2.3 Particulate
Organic Nitrogen
1. 0.7 μm glass fiber filters (25 mm Ø)
2. Concentrated hydrochloric acid (37% HCl).
3. Forceps.
4. Ultrapure water (e.g., Milli-Q).
5. Oven (450
C).
6. Vacuum filtration device with a vacuum pump.
Determining Inorganic and Organic Nitrogen
73
14. 25 ml reaction flasks with screw caps (e.g., Pyrex containers for
manual nitrate analysis).
15. 50 ml graduated cylinders.
16. 100–1000 ml volumetric flasks.
17. 100–1000 ml storage bottles.
18. Spatulas.
19. Adjustable pipettes and pipette tips.
20. Analytical balance.
21. Oven capable of being maintained at 45
C.
22. Refrigerator.
23. 1 cm quartz glass cuvette or flow through cuvette (for manual
nitrate analysis).
24. 5 cm quartz glass cuvette (for manual ammonium analysis).
25. Spectrophotometer or automatic analyzer.
2.2 Dissolved
Organic Nitrogen
(Total Dissolved
Nitrogen)
1. 24 ml glass autosampler vials with screw caps.
2. Oven (450
C).
3. Concentrated hydrochloric acid (37% HCl).
4. Ultrapure water (e.g., Milli-Q).
5. 0.7 μm glass fiber filters (25 mm Ø) and Swinnex filter holders.
6. Disposable 20 ml sterile syringes.
7. Ammonium sulfate (NH 4 SO 4 ).
8. Spatulas.
9. Analytical balance.
10. 100–1000 ml volumetric flasks.
11. Adjustable pipettes, pipette tips.
12. Ultrasonicator bath.
13. Plastic film (e.g., Parafilm).
14. Refrigerator and freezer.
15. CN analyzer with autosampler and instrument specific carrier
gas and oxidizing agents.
2.3 Particulate
Organic Nitrogen
1. 0.7 μm glass fiber filters (25 mm Ø)
2. Concentrated hydrochloric acid (37% HCl).
3. Forceps.
4. Ultrapure water (e.g., Milli-Q).
5. Oven (450
C).
6. Vacuum filtration device with a vacuum pump.
Determining Inorganic and Organic Nitrogen
73