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[Display omitted] • Five kinds of single hydrolyzing bacteria were selected to mineralize long flame coal, and the hydrolysis ways were different. • KEGG metabolic pathway was used to investigate the metabolic process of hydrolytic bacteria. The results showed that acetic acid conversion was the main methanogenesis of bacteria B3, and methylamine conversion was the main methanogenesis of bacteria K2. • According to methane production and microbial activity, B3 was determined to be the best hydrolytic bacterium. The hydrolysis process is the rate-limiting step of coal anaerobic fermentation, and the selection of high-efficiency hydrolysis bacteria determines the hydrolysis of coal efficiency. To optimize the hydrolysis of the coal, five different single hydrolytic bacteria were extracted from long-flame coal for hydrolysis and gas production experiments. The solid–liquid two-phase products after hydrolysis were analyzed by using the Fourier Transform Infrared Spectrometer test (FTIR), three-dimensional Excitation Emission Matrix test (3D-EEM), and Gas Chromatography Mass Spectrometer test (GC–MS). The metabolic differences of the two strains with better degradation effects were analyzed. The results showed that the metabolites in the hydrolysis stage of coal to methane were mainly aromatic compounds and organic acids. The gas production cycle of coal samples without microbial hydrolysis treatment was 27 days, while that with microbial hydrolysis treatment was significantly shortened. The cumulative methane production capacities of the Bacillus polymorpha and Bacillus sphaericus strains were 4.28 mL/g and 3.75 mL/g, respectively. After the coal was degraded by Bacillus polymorpha bacteria, the methane production rate of coal samples was 58.6 %, with the degradation rate constant k was 0.488. Strain Bacillus sphaericus had better transport capacity for amino acids, proteins, and the degradation solution contained more soluble organic matter. The methanogenesis process was dominated by methylamine conversion. The Bacillus polymorpha could degrade aromatic carbon, and its degraded products had the highest content of polymer compounds, organic acids, benzene, and its derivatives. The reaction process could secrete more coenzymes. The methanogenic process mainly involved acetic acid decarboxylation conversion, and its hydrolysis effect was the best. Bacillus polymorpha and Bacillus sphaericus strains screened in this experiment can be used as highly efficiency hydrolytic bacteria to promote anaerobic fermentation to produce methane, which could significantly improve the hydrolysis efficiency. In practical applications, a more suitable on-site hydrolytic bacteria expansion method should be considered, and the feasibility of pure strain application should be fully considered to make it better applied to the bioengineering site of Coalbed methane. [ABSTRACT FROM AUTHOR]

In this research, Ti/SnO 2 –RuO 2 stable anode was successfully prepared by thermal decomposition method, and low concentration cefotaxime sodium (CFX) was degraded by green and sustainable electrocatalytic oxidation technology. The electrocatalytic activity and stability of the Ti/SnO 2 –RuO 2 coating electrode were studied according to the polarization curve of oxygen and chlorine evolution. The effects of current density, initial concentration, pH, electrolyte concentration, and other technological parameters on the degradation efficiency were discussed. Orthogonal experiment results indicated that when the current density was 25 mA cm−2, concentration of electrolyte was 5 mM and the pH value was 7, the best CFX removal rate of 86.33% could be obtained. The degradation efficiency of electrocatalytic oxidation was discussed through electrochemical analysis. Fourier transform infrared spectroscopy was used to analyze the different inlet and outlet stages before and after the degradation of CFX, and the possible degradation process was discussed. Therefore, the electrocatalytic oxidation of Ti/SnO 2 –RuO 2 electrode was a clean and efficient technology, which could be widely used in the treatment of CFX wastewater. [Display omitted] • SnO 2 and RuO 2 are used as dopant to DSA to the degradation of cefotaxime sodium. • Ti/SnO 2 –RuO 2 anode displays excellent stability and electrochemical activity. • ·OH and ClO− play a decisive role in the removal of cefotaxime sodium. • Cefotaxime sodium removal efficiency of 86.33% is reached. [ABSTRACT FROM AUTHOR]

The increase of water temperature caused by the thermal effect of cooling water discharged from power plants has become a major environmental problem, especially its influence on phytoplankton community. The change of water temperature usually reshapes the structure of phytoplankton community. A research combining phytoplankton community and thermal discharge of power plants was conducted to identify the potential influences. Results indicated the average annual water temperature of the reservoir increased gradually by 5–11 °C because of the thermal discharge. Through annual diversity analysis, 139 species or taxa from 6 phyla (i.e. , Bacillariophyta, Chlorophyta, Cyanobacteria, Euglenophyta, Dinoflagellata, and Cryptophyta) were found in different sampling sites, among which Bacillariophyta was the dominant community. Preliminary experimental results revealed the increasing temperature completely reshaped the phytoplankton community structure, especially during the cold season, and this was confirmed by the results of redundancy analysis. In addition, lots of thermophilic genera (i.e. , Synedra , Nitzschia , and Navicula) were detected at sampling station 1 (Spt1) and sampling station 2 (Spt2) where the effect of thermal discharge was the most obvious. The increase in biomass and cell count of Bacillariophyta was the result of thermal effect, especially in cold season. Besides, consequences also revealed some environmental parameters (i.e. , dissolved oxygen concentration, chlorophyll a concentration, and transparency) were affected by the thermal discharge. Chlorophyll a concentration exhibited a slow rising trend while dissolved oxygen concentration and transparency gradually decreased. [Display omitted] • Thermal discharge thoroughly reshaped the phytoplankton community structure. • Thermal effect increased the abundance of Bacillariophyta while weakening others. • Thermal effect on phytoplankton community was more notable in cold seasons. • Phytoplankton possess effective physiological mechanisms for varied temperature. Investigated to the effect of thermal discharge from a power plant on the aquatic environmental parameters and observed change in phytoplankton communities. [ABSTRACT FROM AUTHOR]