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After the closure of the Yudong coal mine, the pH value was approximately 3.0, and the Fe and Mn concentrations reached 380 and 69 mg/L, respectively, in the acid mine drainage (AMD), causing serious pollution to the water bodies in the nearby watershed. Combined with the formation conditions of AMD, the comprehensive treatment technology of source reduction-end treatment is adopted to treat the AMD. The treatment area of the goaf is 0.3 km 3 , the filling and grouting volume is about 6.7 m 3 , and the curtain grouting volume is 4,000 m 3 . Through the grouting and sealing treatment in the goaf, the water volume is reduced to less than 85% of the initial volume (100 m 3 /h). After the end treatment, the pH value of the effluent is around 7.0, the content of Fe and Mn is less than 0.1 mg/L, and the removal rate is above 99%. The project was subsequently operated at RMB 0.85 yuan/t. This project is aimed at the treatment of AMD from small coal mines in complex terrain conditions. It has the characteristics of low cost and high efficiency and can provide an effective treatment technology for AMD in southwestern China and areas with the same geological conditions.

Chinese herbs are a useful resource bank for natural drug development, and have attracted considerable attention to exploit quorum sensing inhibitors (QSIs). This study was designed to screen QSIs from raw Chinese herb materials. Of the 38 common herbs examined, the ethanol extract of Campsis grandiflora flower had the strongest QSI activity. The C. grandiflora flower ethanol extract (CFEE) was purified by HPD600, and the QSI activities were examined in further detail. CFEE inhibited violacein production of Chromobacterium violaceum 026 in a dose-dependent manner, and inhibit the swarming abilities of Escherichia coli K-12 and Pseudomonas aeruginosa PAO1. Furthermore, CFEE could inhibited biofilm formation and destroyed mature biofilms of E. coli K-12 and P. aeruginosa PAO1. The composition of CFEE was determined by UPLC-MS/MS to distinguish active QSI compounds, and 21 compounds were identified. In addition to gallic acid and caffeic acid, two organic acids, malic acid and succinic acid, were confirmed for the first time to have autoinducer type 1 QSI activities. Therefore, CFEE is a potential QSI that could be used as a novel antimicrobial agent and should be considered for medicinal development.

In this study, a resin glycoside fraction with cytotoxic activity was isolated from the alcoholic extract of C. arvensis whole plants. To describe the chemical feature of the resin glycosides, the fraction was alkaline hydrolyzed and four novel glycosidic acids, named arvensic acids A-D (1-4), were isolated. Their structures were thoroughly elucidated on the basis of spectroscopic data and chemical evidences. They all possess a same heptasacharride core, consisting of one D-fucose, two L-rhamnose and four d-glucose units. The difference among these glycosidic acids was placed on the aglycone, which is 12S-hydroxypentadecanoic acid for 1, 12S-hydroxyhexadecanoic acid for 2, 3S,12S-dihydroxypentadecanoic acid for 3, and 3S,12S- dihydroxyhexadecanoic acid for 4. These aglycones are rarely found in the structures of resin glycosides and are firstly identified in the genus Convolvulus., (Copyright © 2018. Published by Elsevier B.V.)

Objective: The aim of this study was to screen acid-producing strains from the broth of psychrotolerant biogas fermentation and evaluate the acid-producing character of them., Methods: Acid-producing strains were isolated by a medium with methyl red at 4 degrees C in Petri dishes and identified by morphology observation and 16S rRNA sequencing. Moreover, the ability of hydrolysis of starch, fermentation of carbohydrates, liquefaction of gelatin and production of catalase were studied., Results: Two acid-producing strains (FJ-8 and FJ-15) were isolated. The result of the 16S rRNA phylogenetic tree shows that FJ-8 and FJ-15 belong to Pseudomonas sp. and Shewanella sp., respectively. Both FJ-8 and FJ-15 could hydrolyze starch, liquidize gelatin and produce catalase. The optimum temperature for acid-producing of FJ-8 and FJ-15 is 15 degrees C and 20 degrees C, respectively. After 10 days cultivation at 4 degrees C, the concentration of acetic acid was 792 mg/L and 966 mg/L of FJ-8 and FJ-15, respectively., Conclusion: The selected strains, FJ-8 and FJ-15, have the potential to produce acids at low temperature.

The surface layer of sediment and overlying water samples of Foshan Waterway, a typical municipal polluted river in Pearl River Delta, have been sampled and analyzed. The analytical items of sediment and overlying water include AVS, Eh, SEM(Pb), SEM(Cd), SEM(Cu), SEM(Zn), SEM(Ni), SEM(Cr), and Eh, DO, respectively. The benthic macroinvertebrate investigation has been done at the same time in the same place. Combing the results above, the relationship between AVS and heavy metals biotoxicity in Foshan waterway has been discussed. The main object is to examine if the SEM-AVS criterion is valid in judging the biotoxicity of heavy metals in the heavily polluted river. The range of AVS is from 0.339 micromol/g to 69.579 micromol/g, with the average of 20.283 micromol/g. The maximum sigmaSEM5 (Sum of SEM(PB), SEM(Cd), SEM(Cu), SEM(Zn), SEM(Ni)) is 23.067 micromol/g, while the minimum is 1.062 micromol/g. Both the species and quantity of benthic macroinvertebrate are little, and most of them belong to pollution bearable species, with Limnodrilus sp. as dominative species. There are 9 sampling stations where the sigmaSEM5-AVS are below zero, and the analytical results of Non-matric multi-dimentional scaling (MDS) indicate the benthic community structure of 7 sampling stations among them are similar. It means that the heavy metals biotoxicity in the heavily polluted river has close relationship with the value of SEM-AVS. It also proves that heavy metals biotoxicity in sediment is complicated, which can't be explained by SEM-AVS completely.

The montmorillonite sample from Heping, China had been studied by chemical analysis, XRD, IR, AFM and MAS NMR. The results showed that acid concentration had much influence on surface structure of montmorillonite. When the acid concentration reached 2M, the Q3Si structure in silica-oxygen tetrahedron recombined, some Q3Si structure in montmorillonite transformed to distortion Q3Si structure and Q4Si structure. However, the structure of Al had no changes, according with the observation results of atomic force microscope. The Brønsted acid site of montmorillonite increases with the accretion of the concentration of acid activation, while oversize concentration of acid activation will decrease the surface site of montmorillonite.

More than 30 aerosol samples were collected from 1 place near Zaojiaban Road (downtown of Shanghai) and 1 village near Jiading country (suburb) by a stacked-filter air sampler. The coarse particulates (>2.5 microm) and the fine particulates (PM2.5) and their unsoluble parts were analyzed by proton-induced X-ray emission. The cytotoxicity of particulates from the two places was evaluated by malondialdehyde (MDA) and thiazolyl blue (MTT) methods. The results show that the transition metal Fe, Cr, and Mn compounds from downtown are more easily soluble than those from the suburb, both in coarse and fine particulates, and the S content is much higher in particulates from downtown than that from the suburb. The cytotoxicity of the particulates from downtown is higher than that from the suburb and the cytotoxicity of acidified particulates is significantly higher than that of the controls. Because there are higher-soluble transition metal compounds that can induce free radicals in acidified particulates, the soluble transition metals may be one of the main factors for cytotoxicity.