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Measurement of Humic Substance in Tap Water (3D Fluorescence Spectra)

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Measurement of Humic Substance in Tap Water (3D Fluorescence Spectra) Measurement of Humic Substance in Tap Water (3D Fluorescence Spectra) INTRODUCTION Humic substances are dissolved organic matters contained in environmental water such as river and lake water. Humic substances, depending on their forms, have different fluorescence properties and thus, the fluorescence spectrum analysis is a useful analysis method for the identification of humic substances. This time, the humic substances contained in tap water were analyzed by a fluorophotometer. By analyzing the fluorescence spectrum, the decrease in the amount of the humic substances in the tap water treated with a home use water purifier was confirmed. By using the F-7000 fluorophotometer, the data is obtained at the ultra-high scan speed of 60000 nm/min and therefore, the fluorescence properties can be easily confirmed even when a large number of samples are to be analyzed. In addition, the instrument has the highest sensitivity for the instrument class and is suitable for the analysis of trace humic substances contained in samples such as tap water. SAMPLE ACCESSORY SAMPLE: Tap water (untreated, treated with a water purifier) Fluorophotometer cell: 10 mm rectangular cell (Sampling location: Hitachinaka-shi, Ibaraki) (synthetic quartz, four-side transparent) ANALYSIS CONDITIONS Instrument : F-7000 Slit on excitation side : 10 nm Filter : GG295 Photomultiplier Vol. : 650V Slit on fluorescence side : 10 nm Response : Automatic Full scale : 1000 Scan speed : 60000 nm/min Detector : R928F Contour line interval : 25 Excitation Excitation Wavelength (nm) Wavelength (nm) Fluorescence Fluorescence 500 Ex/Em 500 Ex/Em intensity intensity 1 : 240 / 410 nm 962.5 1 : 230 / 425 nm 330.3 2 : 310 / 410 nm 475.1 2 : 310 / 425 nm 85.84 400 400 ● ● 300 300 ● ● 200 200 300 400 500 600 300 400 500 600 Fluorescence wavelength (nm) Fluorescence wavelength (nm) 3D Spectrum of Tap Water (Untreated) 3D Spectrum of Tap Water (Treated with Water Purifier) x The amount of the humic substances in tap water varies depending on the sampling locations, seasons, treatment processes at water purification plants. x This data sheet does not warrant the performance of the home-use water purifier. KEY WORDS Environmental Analysis Related, Environmental Water, Humic Substance, Fluorophotometer (FL) Tap Water, Dissolved Organic Matter, Clean Water, Treated Water, Humic Acid, Fulvic Acid, Filter, Filtration, Sheet No. FL110013-01 3D Fluorescence Spectrum, 3D, FL, F-7000 Hitachi High-Technologies Corporation Measurement of Humic Substance in Tap Water (Comparison of Fluorescence Method and Absorption Method) INTRODUCTION Humic substances are dissolved organic matters contained in environmental water such as river and lake water. Humic substances, depending on their forms, have different fluorescence properties and thus, the fluorescence spectrum analysis is a useful analysis method for the identifications of humic substances. This time, the humic substances contained in tap water were analyzed by a fluorophotometer. By analyzing the fluorescence spectrum, the decrease in the amount of the humic substances in the tap water treated with a home use water purifier was confirmed. One of the methods used to analyze the contents of organic matters is UV absorption spectrum analysis. However, in samples such as tap water, the concentrations of humic substances are low. As there is no sufficient difference between the absorbances, it is difficult to confirm the effects of water purifiers by the UV analysis. The fluorescence spectrometric analysis, especially with the F-7000 fluorophotometer which has the highest sensitivity for the instrument class, is suitable for the analysis of trace humic substances. SAMPLE ACCESSORY SAMPLE : Tap water (untreated, treated by water purifier) Fluorophotometer cell: 10 mm rectangular cell (synthetic quartz, four-side transparent) (Sampling site: Hitachinaka-shi, Ibaraki) Spectrophotometer cell: 10 mm rectangular cell (synthetic quartz, two-side transparent) ANALYSIS CONDITIONS Instrument : F-7000 Slit on fluorescence side : 10 nm Response : Automatic Excitation wavelength : 310 nm Scan speed : 240 nm/min Detector : R928F Slit on excitation side : 10 nm Filter : GG295 Photomultiplier Vol.: 650 V Instrument : U-3900 Scan speed : 300 nm/min Sampling interval : 1 nm Measurement wavelength range: 200 - 400 nm Slit : 5 nm Control : Ultrapure water Tap water (untreated) Tap water (untreated) 1000 Tap water (treated with water purifier) Tap water (treated with water purifier) 1.0 800 0.8 Fluorescence intensity: 469.7 600 0.6 Fluorescence intensity: 400 79.76 0.4 Absorbance (Abs) Absorbance 200 0.2 Relative fluorescence intensity 0 0 300 400 500 200 300 400 Fluorescence wavelength (nm) Wavelength (nm) Fluorescence Spectrum of Tap Water Absorption Spectrum of Tap Water (Untreated, Treated with Water Purifier) (Untreated, Treated with Water Purifier) x The amount of humic substances varies depending on the sampling locations, seasons, and treatment processes at water purification plants. x This data does not warrant the performance of the home use water purifier. KEY WORDS Fluorophotometer (FL) Environmental Analysis Related, Environmental Water, Humic Substance, Tap Water, Dissolved Organic Matter, Clean Water, Treated Water, Humic Acid, Fulvic Acid, Filter, Filtration, Fluorescence Spectrum, Sheet No. FL110013-02 Absorption Spectrum, FL, F-7000, UV, U-3900 Hitachi High-Technologies Corporation.
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