Three-dimensional fluorescence excitation–emission matrix (EEM) spectroscopy with regional integration analysis for assessing waste sludge hydrolysis treated with multi-enzyme and thermophilic bacteria

Insights into the respective role of acidification and oxidation for enhancing anaerobic digested sludge dewatering performance with Fenton process

“…Peaks at intermediate excitation wavelengths (250-280 nm) and shorter emission wavelengths (<380 nm) are related to soluble microbial byproduct-like material (Region IV) while peaks located at the excitation wavelengths (200-250 nm) and the emission wavelengths (>380 nm) represent fulvic acid-like substances (Region III). Peaks at longer excitation wavelengths (>280 nm) and longer emission wavelengths (>380 nm) are related to humic substances (Region V) (Chen et al, 2003;Guo et al, 2014). The influence of pH on dissolved biopolymers located in different fluorescent regions was presented in Table 2.…”

Enhancement of volatile fatty acid production by co-fermentation of food waste and excess sludge without pH control: The mechanism and microbial community analyses

“…The FRI, a quantitative technique that integrates volumes beneath different excitation-emission regions in EEM spectra, was used to quantitatively analyze EEM spectra of dissolved organic matter (DOM) (Yu et al, 2015). EEM peaks were divided into five regions, including simple aromatic proteins such as tyrosine (Region I) and tryptophan (Region II), fulvic acidlike substances (Region III), soluble microbial by-product-like materials (Region IV) and humic acid-like organics (Region V) (Guo et al, 2014). The volume beneath region ''i" of the EEM is / i .…”

Investigating Influence of Hydrological Regime on Organic Matters Characteristic in a Korean Watershed

“…Silt widths of the emission and excitation were set to a 5 nm bandwidth; with a 3000 nm/min scan speed. The EEM results were characterized by the fluorescence regional integration (FRI) method [30]. FRI divided the result into five regions based on the excitation and emission wavelength: (1) aromatic proteins group at region I and II where excitation wavelength is lower than 250 nm and emission wave length is lower than 350 nm, (2) fulvic acid organic group at region III where excitation wavelength is lower than 250 nm and emission wavelength is lower than 350 nm, (3) soluble microbial byproduct-like material group originating from microbial activity at region IV where excitation wavelength is lower than 280 nm and emission wavelength is lower than 380 nm, (4) humic acid-like organic group at region V where excitation wavelength is greater than 280 nm and emission wavelength is greater than 380 nm.…”