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Wastewater with residual streptomycin sulphate usually contains high content of ammonia-nitrogen. However, the biological removal process of ammonia-nitrogen under streptomycin sulphate circumstance was unclear. In this study, short-term and long-term effects of streptomycin sulphate on biological nitrification systems, including AOB, NOB, SAOR, SNOR and SNPR, were evaluated comprehensively. The results indicated IC50 for AOB and NOB were 7.5 and 6.6 mg/L. SAOR and SNPR could be decreased to 3.43 ± 0.52 mg N/(g MLSS·h) and 0.24 ± 0.03 mg N/(g MLSS·h) while the addition of streptomycin sulphate was 10 mg/L. When streptomycin sulphate addition was stopped, nitrification ability recovered slightly, SAOR and SNPR increased to 9.37 ± 0.36 mg N/(g MLSS·h) and 1.66 ± 0.49 mg N/(g MLSS·h), respectively. The protein of EPS increased gradually during the acclimatization process, and the maximal protein value was 68.24 mg/g MLSS on the 100th day, however, no significant change of polysaccharose was observed during the acclimatization process. High abundance of ARGs and intI1 was detected in effluent and sludge of the biological treatment system. The maximal relative abundance of aadA1 in the sludge appeared on the 140th day, and increased by 0.99 orders of magnitude. Biological diversity decreased significantly during the acclimatization process, relative abundance of nitrosomonas was changed from 9.07% to 38.68% on the 61st day, while relative abundance of nitrobacter was changed from 1.30% to 0.64%. It should be noted that relative abundances of nitrosomonas and nitrobacter were reduced to 16.17% and 0.25% on the 140th day. This study would be helpful for nitrogen removal in wastewater with antibiotic.

Red mud/biochar composite material (RMBC), which was applied as heavy metal passivator in this research, was prepared with red mud (the bauxite residue) and cornstalk under anoxic sintering condition. Based on the batch experiments in Pb contaminated soil, the passivating properties of several materials, including red mud (RM), biochar (BC), RMBC and phosphate-containing RMBC (PRMBC), were investigated in comparison with each other. Some interesting results are as follows: through anoxic thermal activation, a rough and porous structure of RMBC was obtained. Substances such as Fe

This study developed an electrochemical sensor for Mn2+ assay in Baijiu based on TiO2-NH2@COFDPTB nanocomposite, which was synthesized via the controllable growth of COFDPTB onto the surface of TiO2-NH2 using the Schiff-base condensation reaction.

Biotrickling filters (BTFs) for hydrophobic chlorobenzene (CB) purification are limited by mass transfer and biodegradation. The CB mass transfer rate could be improved by 150 mg/L rhamnolipids. This study evaluated the combined use of Fe3+ and Zn2+ to enhance biodegradation in a BTF over 35 day. The effects of these trace elements were analysed under different inlet concentrations (250, 600, 900, and 1200 mg/L) and empty bed residence times (EBRTs; 60, 45, and 32 sec). Batch experiments showed that the promoting effects of Fe3+/Zn2+ on microbial growth and metabolism were highest for 3 mg/L Fe3+ and 2 mg/L Zn2+, followed by 2 mg/L Zn2+, and lowest at 3 mg/L Fe3+. Compared to BTF in the absence of Fe3+ and Zn2+, the average CB elimination capacity and removal efficiency in the presence of Fe3+ and Zn2+ increased from 61.54 to 65.79 g/(m3⋅hr) and from 80.93% to 89.37%, respectively, at an EBRT of 60 sec. The average removal efficiency at EBRTs of 60, 45, and 32 sec increased by 2.89%, 5.63%, and 11.61%, respectively. The chemical composition (proteins (PN), polysaccharides (PS)) and functional groups of the biofilm were analysed at 60, 81, and 95 day. Fe3+ and Zn2+ significantly enhanced PN and PS secretion, which may have promoted CB adsorption and biodegradation. High-throughput sequencing revealed the promoting effect of Fe3+ and Zn2+ on bacterial populations. The combination of Fe3+ and Zn2+ with rhamnolipids was an efficient method for improving CB biodegradation in BTFs.

CircPRTM5 is associated with cell proliferation and migration in many kinds of malignancies. However, the functions and mechanisms of CircPRTM5 in CRC progression remain unclear. We explored the role and the mechanisms of CircPRTM5 in the development of CRC. Tissues of CRC patients and matched adjacent non‐tumour tissues were collected to evaluate the expression of CircPRTM5. The expression of CircPRTM5 in CRC tissues was significantly higher than that in adjacent tissues. The biological functions of CircPRTM5 in CRC were determined by overexpression and down‐regulation of CircPRTM5 in CRC cells in vitro and in vivo. The results indicate that knockdown of CircPRTM5 can significantly inhibit the proliferation of CRC cells. The potential mechanisms of CircPRTM5 in CRC development were identified by RT‐qPCR, Western blotting analysis and luciferase reporter assay. CircPRTM5 competitively regulates the expression of E2F3 by capillary adsorption of miR‐377. CircPRMT5 regulates CRC proliferation by regulating the expression of E2F3, which affects the expression of the cell cycle‐associated proteins cyclinD1 and CDK2. CircPRTM5 exerts critical regulatory role in CRC progression by sponging miR‐377 to induce E2F3 expression.

In this study, the effect of rhamnolipids (RL) on m-dichlorobenzene (m-DCB) removal and biofilm was investigated in two biotrickling filters (BTF) (BTF1: blank control; BTF2: RL addition). The critical micelle concentration (CMC) value of RL was 75.6 mg L

Biofilms drive crucial ecosystem processes in rivers. This study provided the basis for overall quantitative calculations about the contribution of biofilms to the nitrogen cycle. At the early stage of biofilm formation, dissolved oxygen (DO) could penetrate the biofilms. As the biofilm grew and the thickness increased, then the mass transfer of DO was restricted. The microaerobic layer firstly appeared in biofilm under the turbulent flow conditions, with the appearance of the microaerobic and anaerobic layer, the nitrification and denitrification reaction could proceed smoothly in biofilm. And the removal efficiency of total nitrogen (TN) increased as the biofilm matured. Under the turbulent flow conditions, mature biofilms had the smallest thickness, but the highest proportion the anaerobic layer to the biofilm thickness, the highest density, and the highest nitrogen removal efficiency. However, the nitrogen removal efficiency of biofilm was the lowest under laminar flow conditions. The difference of layered structure of biofilm and the DO flux in biofilm explained the difference of nitrogen migration and transformation in river water under different hydrodynamic conditions. This study would help control the growth of biofilm and improve the nitrogen removal capacity of biofilm by regulating hydrodynamic conditions.

Microbial biofilms are common on abiotic and biotic surfaces, especially in rivers, which drive crucial ecosystem processes. The microorganisms of biofilms are surrounded by a self-produced extracellular polymeric substance (EPS). In this study, we investigated the effects of different hydrodynamic conditions on the composition, spatiotemporal distribution of different extracellular polymeric substances, and the architecture of biofilms. Multidisciplinary methods offer complementary insights into complex architecture correlations in biofilms. The biofilms formed in turbulent flow with high shear force were thin but dense. However, the biofilms formed under laminar flow conditions were thick but relatively loose. The thickness and compactness of the biofilms formed in the transitional flow were different from those of the other biofilms. The compact structure of the biofilm helped to resist shear forces to minimize detachment. Under the turbulent flow condition, bacteria, exopolysaccharides, and extracellular proteins permeated through the biofilm, and more extracellular polysaccharides enveloped bacteria and extracellular proteins. However, under the transitional flow condition, the extracellular polysaccharides and proteins were fewer than those under the turbulent flow condition; bacteria and algae were seen more prominently in the upper layer of the biofilm. Under the laminar flow condition, the distribution of extracellular polysaccharides, extracellular proteins, and bacteria was relatively uniform throughout the biofilm. The number of extracellular polysaccharides was greater than that of extracellular proteins. The total number of EPS in the biofilm was the largest under turbulent flow condition, followed by that under transitional flow condition and then under laminar flow condition. This study also observed that soluble EPS (S-EPS) were secreted first, followed by loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS). In particular, the adhesion of LB-EPS and flocculation capability of TB-EPS play some role in regulating biofilm formation. This study would help to perfect the five-stages theory of biofilm formation.

Biofilters usually have poor VOC removal performance at temperatures lower than 20 °C. In this study, two quorum sensing (QS) enhancement methods, which are addition of exogenous N-acyl-homoserine lactones (AHLs) and inoculation of AHL-producing bacteria, were applied in biofilters treating gaseous toluene at a low temperature of 12 °C. Their effects on biofilter performance and biofilm characteristics were investigated. The results showed that adding exogenous AHLs and AHL-producing bacteria in biofilters raised the average toluene elimination capacity by 39% and 26% respectively, and raised the average mineralization efficiency by 25% and 47% respectively in first 24 days. In addition, the two QS enhancement methods could increase the attached biomass by 48% and 87% respectively and made the biofilm distribute more uniform by increasing its extracellular polymeric substances content and microbial adhesive strength. The two QS enhancement methods resulted in more mesopores in biofilm, lower O/C and (O+N)/C of organic elements in biofilm, and increased the solubility of toluene in liquid phase, which all benefit VOCs mass transfer in biofilters. These results demonstrate that QS enhancement methods have the potential to optimize the biofilm and thus improve the performance of biofilters treating VOCs at a low temperature. This work provides us a new choice to improve industrial-scale biofilters treating VOCs at high latitude regions or in winter.

Sudden odor incidents occurring in the source water have been a severe problem for water suppliers. In order to apply emergency control measures effectively, it is necessary to identify the target compounds responsible for odor incidents rapidly. The present work identified the odorants and explored emergency disposal mechanisms for sudden and severe odors in the QT River's drinking water source (HZ city, China). Medicinal, chemical, septic, and musty odors with strong intensities were detected in the source water. The effect of conventional treatments of drinking water treatment plant (DWTP) on odors' removal was limited, which was evident by the presence of medicinal, chemical, and musty odors with moderate intensities in the effluent of DWTP. Total seventeen odorants were identified successfully in the source water of QT River and the effluent of DWTP. The measured OAVs and reconstituting the identified odorants explained 87%, 87%, 89%, and 94% of medicinal, chemical, septic, and musty odors, respectively, in the source water of the QT River and 90%, 87%, and 88% of medicinal, chemical, and musty odors in the effluent. Styrene, phenol, 2-chlorophenol, 2-tert-butylphenol, and 2-methylphenol were associated with the medicinal odor, while propyl sulfide, diethyl disulfide, propyl disulfide, and indole were related to the septic odor. Geosmin and 2-methylisoborneol (2-MIB) were responsible for the musty odor, and cyclohexanone, 1,4-dichlorobenzene, and nitrobenzene were involved with the chemical odor. Based on the characteristics of identified odorants, powdered activated carbon (PAC) was applied to control the odors in the QT River. The results indicated that the medicinal, chemical, septic, and musty odors could be removed entirely after adding 15 mg/L PAC, which effectively controlled emergency odor problems. Overall, the study would offer a scientific basis and operational reference for emergency odor management and control in DWTP with similar complicated odor incidents.

M-dichlorobenzene can be degraded through biotrickling filter (BTF). However, its degradation needs to be enhanced, and the mechanism of enhancement is unclear. In this study, Zn(II) was taken as the biological growth promoter; the polysaccharides and proteins, zeta potential, Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, and the enzyme activity of the strains were analyzed. The results indicated that Zn(II) at 5mg/L promoted the growth of the strain. When the inlet concentration was 505.74 mg/m3 and the empty bed resistance time (EBRT) was 90 s, the removal efficiency of BTF2 was 86.15%. In BTF2, the enzyme activity, polysaccharide, and protein content increased, while the zeta potential decreased. The changes of zeta potential indicated that there existed an electrostatic interaction between extracellular polymeric substance (EPS) and Zn(II). The results of Fourier transform infrared spectroscopy and x-ray photoelectron spectroscopy confirmed that there was a bond between the EPS surface functional groups and Zn(II).

The odor problems in river-type micro-polluted water matrixes are complicated compared to those in lakes and reservoirs. For example, the TY River in Jiangsu Province has been associated with complex odors, whereas the specific odor compounds were not clear. In this paper, a comprehensive study on characterizing the odors and odorants in source water from the TY River was conducted. Six odor types, including earthy, marshy, fishy, woody, medicinal, and chemical odors, were detected for the first time; correspondingly, thirty-three odor-causing compounds were identified. By means of evaluating odor activity values and reconstituting the identified odorants, 95, 93, 92, 90, 89 and 88% of the earthy, marshy, fishy, woody, medicinal and chemical odors in the source waters could be clarified. Geosmin and 2-methylisoborneol were associated with earthy odor, while amyl sulfide, dibutyl sulfide, propyl sulfide, dimethyl disulfide, dimethyl trisulfide and indole were related to marshy odor. The major woody and fishy odor compounds were vanillin, geraniol, β-cyclocitral and 2,4-decadienal, 2-octenal, respectively. Medicinal and chemical odors were mainly caused by 2-chlorophenol, 4-bromophenol, 2,6-dichlorophenol and naphthalene, and 1,4-dichlorobenzene, respectively. This is the first study in which six odor types and thirty-three odorants were identified simultaneously in a river-type micro-polluted water source, which can offer a reference for odor management in drinking water treatment plants.

Here, a new porous graphene (PGR) based nanocomposite was synthesized by a chemical and thermal reduction of graphite oxide in the assistance of calcium lignosulfonate (CLS), and characterized by scanning electron microscopy SEM, TEM, XPS, Zeta potential analysis, FTIR and EIS. Then the as-prepared CLS/PGR was used along with Nafion to modify a glassy carbon electrode (GCE) for constructing electrochemical sensor to detect Pb2+ and Cd2+ simultaneously. Compared with the bare GCE, the reduced graphene oxide/GCE, and the CLS/PGR/GCE, the Nafion/CLS/PGR/GCE exhibited improved electrochemical performance in detecting the two ions. It could be ascribed to the synergistic contribution from PGR, CLS and Nafion, which integrated the advantageous features of high active surface area, good cation exchange ability and strong adsorption capacity. Under optimum conditions, this novel sensor showed a wide detection range for Pb2+ and Cd2+ (0.05–5.0 μM) with the limit of detection and limit of quantification for Pb2+ 0.01 and 0.03 μM, for Cd2+ 0.003 and 0.01 μM, respectively. It was successfully applied for the simultaneous determination of Pb2+ and Cd2+ in real water samples with satisfying recoveries of 93.6–105.3% for Pb2+ and 93.5–102.5% for Cd2+, demonstrating its feasibility for the determination of environmental metallic pollutants.

A strain, Brevibacillus agri DH-1, isolated from dry lands was used to remove m -dichlorobenzene. After 48 h culturing, the concentrations of m -dichlorobenzene decreased from 26–130 to 7.87–28.87 mg/L and dry cell weight for bacterial growth reached 52.43–75.05 mg/L. The growth and degradation kinetics were analyzed by the fitting of Haldane-Andrews model and pseudo first-order model. A degradation pathway was proposed according to major intermediates (phenol), chloride ion variation, ring-opening enzyme activity, and high mineralization (0.47 g Cl- /g m -dichlorobenzene , 0.65 g co2 /g m -dichlorobenzene , 0.15 g DCW /g m -dichlorobenzene ). In addition, the performance in a biotrickling filter (BTF) was evaluated through removal efficiency and pressure drop values with increasing inlet loading rate from 4.10 to 122.57 g/m 3 /h at three empty bed residence time points (30 s, 60 s, and 90 s). The results demonstrated that strain DH-1 possessed high removal efficiency and stable operation in a BTF.

Polyurethane (PU) sponges are popular packing material in biofilters and their smooth and hydrophobic surface often leads to an uneven distribution and detachment of biofilms. In this work, the surface of PU sponge was modified to obtain higher roughness and positive charge. The performances of two biofilters (BF1 with pristine sponge and BF2 with modified sponge) for benzene, toluene, ethylbenzene, and xylene (BTEX) removal were investigated. Total Volatile Organic Compound (TVOC) removal efficiency and CO2 increment were 61% and 804 ppm for BF2 respectively after start-up, compared with 51% and 538 ppm for BF1. Analysis on biofilms showed that the modification of PU sponge significantly improved the microbial growth, viability and adhesive strength in biofilms, reduced extracellular polymeric substance (EPS) and changed the microbial community. These results demonstrate that modified sponge can enhance biofilm formation and BTEX removal in biofilters and may applied in large-scale applications.

Herein, Fe3O4@Ru-doped TiO2 photocatalyst was developed successfully by a facile chemical strategy. The sample with 0.2% doping Ru showed the best photocatalytic activity, which could photodegrade 70.20% of methylene blue after 120 min of simulated sunlight exposure, and kept good degradation efficiency and recovery after 5 cycles. It could be attributed that the Ru-doping alleviated the band gap energy to make the electron-hole pairs easier to generate and enhanced the synergistic effect to increase the carrier separation efficiency. The present work provided a development prospect of simple preparation of recoverable photodegradation catalyst for environmental organic pollutants.

Ozone and biological activated carbon (BAC) are known to be effective at removing odors in drinking water. However, the specific variations in complex odors and odorants along the course of advanced treatments in full-scale drinking water treatment plants (DWTP) have remained unclear. In this paper, the migration of odors and odorants through pre-ozonation, sedimentation, post-ozonation, and BAC treatment processes were studied from January to December 2019 in a DWTP. The results indicated that septic, musty, and chemical odors with intensities of 6-6.7, 6-7.5, 4-5 could be removed by both ozonation and BAC, while grassy, fishy odors with intensities of 3.3-4.8, 2.3-5.8 could not be removed until the BAC step. Twenty-four odorants identified in raw water were classified as musty (2-methylisoborneol, geosmin), chemical (e.g. indane, eucalyptol), septic (e.g. dimethyl disulfide, pentanethiol), fishy (2,4-decadienal) and grassy (nonanal, decanal) odor compounds. It is noteworthy that eleven additional odorants were produced after ozonation; in addition, the concentrations of fishy and grassy odorants were increased after ozonation, and the concentrations of musty, septic, fishy, and grassy odorants were increased after sedimentation, suggesting that sedimentation and ozonation should be carefully managed. BAC was the most effective at removing the above odorants simultaneously. This study would be helpful for providing more insights into the migration of odorants along treatment processes and understanding the mitigation of odors in DWTPs using raw waters with complex odors.

WO3 thin films loaded with Pt–Ag bimetallic alloy nanoparticles were successfully synthesized by a three-step method involving the formation of a homogeneous precursor sol, spin coating as well as UV-light reduction, and calcination. Moreover, a systematic, comparative study of the microstructure, chemical environment and electrochemical characteristics of the as-prepared Pt/WO3, Ag/WO3, and Pt–Ag/WO3 thin films was carried out. It was found that the Pt–Ag/WO3 thin film exhibited a highly enhanced photocatalytic performance for the degradation of methylene blue solution compared with the pure WO3, Pt/WO3 and Ag/WO3 thin films. Based on the experimental results and the energy-band diagrams, the transfer paths of photogenerated charges and the enhanced photocatalytic mechanism were proposed. It was suggested that the photogenerated electrons from the conduction band of WO3 first transferred to Ag and then to Pt in the Pt–Ag/WO3 sample during the photocatalytic process, promoting the efficient two-electron reduction of O2 compared to in the Pt/WO3 and Ag/WO3 samples. In addition, this process prevented the oxidation of Ag in the Pt–Ag/WO3 sample during the photodegradation process in air. Overall, this study provides a novel approach to design efficient photocatalysts decorated by bimetallic alloy nanoparticles.

In this work, ceramic pellets were used as packing material to establish a biotrickling filter (BTF) with acclimated sludge being inoculated on the surface of the packing to purify waste gas containing styrene. A method of toluene-styrene secondary acclimation was applied to achieve rapid formation of biological films. Results showed that the total time of start-up was 48 days and the removal efficiency (RE) of styrene reached up to 95%. The suitable empty bed residence time (EBRT) was obtained that is 57 s for higher RE of styrene with the inlet loading rates of 6.7–271.6 g/m3/h. The pH and moisture content showed small effect on styrene removal indicating that the operation of BTF was stable. Biomass accumulation was normal and its rising velocity under the condition of short EBRT was faster than that of long EBRT.

The use of pentachlorophenol (PCP) was banned or restricted in many countries worldwide because of its adverse influences on the ecological environment and humans. However, the potential disrupting effects of PCP on denitrifying microorganisms have warranted more analysis. In this study, the impacts of PCP on denitrification were investigated by using Paracoccus denitrificans as a model denitrifying bacterium. Compared with the control, the presences of 10 and 50 μM of PCP were found to significantly decrease the denitrification efficiencies from 98.5 to 87.2% and 68.7%, respectively. The mechanism studies showed that PCP induced the generation of reactive oxygen species, which decreased the vital enzymes activities related to glycolysis process, causing the disturbance of the metabolism of P. denitrificans utilizing carbon source (glucose) and the growth of the cell, and subsequently the generation of electron donor (NADH) for denitrification via NAD+ reduction was severely depressed. Further studies indicated that PCP also decreased the genes expression of several key enzymes responsible for denitrification, such as napA of nitrate reductase (NAR), nirS of nitrite reductase, norB of nitric oxide reductase, and nosZ of nitrous oxide reductase; however, there was only the enzyme activity of NAR was remarkably inhibited.

The aim of this study was to evaluate the influence of rhamnolipid (RL) and ferric ions on the performance of a biotrickling filter (BTF) for the removal of gas-phase 1,2-dichlorobenzene (o-DCB). A comprehensive investigation of microbial growth, pollutant solubility, extracellular polymeric substances (EPS) and enzymatic activity in o-DCB degradation by an isolated strain Bacillus cereus DL-1 with/without RL and Fe3+ were carried out using batch microcosm experiments. In addition, o-DCB removal performance, biofilm morphology, and microbial community structures in two identical lab-scale biotrickling filters (named BTF1 and BTF2) inoculated with strain DL-1 were studied. The batch microcosm experiments demonstrated that 120 mg L−1 RL and 4 mg L−1 Fe3+ could enhance the biodegradation of o-DCB, which may be due to promotion on bacterial growth, o-DCB solubilization, C12O enzyme activity, and polysaccharide (PS) and protein (PN) in EPS. Fourier transform infrared (FTIR) spectra indicated that the addition of RL with Fe3+ had notable effects on the functional groups of PS and PN in EPS. The experimental results in BTFs indicate that the removal efficiency of o-DCB decreased from 100% to 56.4% for BTF1, which was not fed with RL and Fe3+, and from 100% to 80.3% for BTF2, which was fed with RL and Fe3+, when the inlet loading rate increased from 4.88 to 102 g m−3 h−1 at an empty bed residence time of 60 s. In addition, the microbial adhesive strength and the microbial community structure were different among both BTFs, highlighting the positive effects of RL and Fe3+.

In this study, the effect of rhamnolipid and Mg (II) on microbial growth and 1,3-dichlorobenzene removal was investigated in two identical lab-scale biotrickling filters (named BTF1 and BTF2). The contact angle and Henry’s constant were detected at various concentrations of rhamnolipid and the results indicated that rhamnolipid is able to effectively improve the solubility of 1,3-dichlorobenzene in medium. The results of the experiments in BTFs showed that the optimal concentrations of rhamnolipid and Mg (II) were 170 mg/L and 2 mg/L, respectively. The removal efficiency (RE) of 1,3-dichlorobenzene decreased from 100% to 57.13% for BTF1 that was not fed with rhamnolipid and Mg (II) and from 100% to 86.26% for BTF2 that was fed with rhamnolipid and Mg (II) when the inlet loading rate increased from 2.87 to 83.83 g/(m3 h) at an empty bed residence time (EBRT) of 60 s. The dissolved oxygen (DO) was analyzed throughout the entire period and the results showed that the two additives can significantly promote oxygen transfer. In addition, the microbial adhesive strength and community were observed and compared to show the positive role of rhamnolipid and Mg (II).

In this study, m-xylene biodegradation was examined in bacteria-water mixed solution and biotrickling filter (BTF) systems amended with the nonionic surfactant Tween 80. The mixed bacteria were obtained from the activated sludge of a coking plant through a multisubstrate acclimatization process. High-throughput sequencing analysis revealed that Rhodanobacter sp. was the dominant species among the mixed bacteria. In the bacteria-water mixed solution, the bacterial density increased with increasing Tween 80 concentration. Hence, Tween 80 could be utilized as substrate by the mixed bacteria. Tween 80, with concentrations of 50-100 mg LThe integrated application of mixed bacteria and surfactant was demonstrated to be a promising approach for the highly efficient removal of m-xylene. Surfactant can activate mixed bacteria to degrade m-xylene by increasing its bioavailability. Besides, surfactant can be utilized as carbon source by the mixed bacteria so that the growth of mixed bacteria can be promoted. It is expected that the integrated application of both technologies will become more common in future chemical industry.

miR-335 and miR-34a are two microRNAs (miRNAs) usually downregulated in gastric cancer (GC). But, their exact regulative roles were not fully elucidated. In this study, we studied the association between miR-335 and/or miR-34a expression and overall survival of GC patients and explored the regulative role of miR-335 and -34a over survivin expression and GC cell growth and invasion. Fifty patients with GC were regularly followed up from 2011 to 2015. miRNA microarray was used to examine the expression trend of miRNAs in eight tumor tissue samples and adjacent normal tissue samples. The possible binding site between miR-335 and survivin messenger RNA (mRNA) was predicted using online database and verified using qRT-PCR, Western blot, and dual luciferase assay. The regulative role of miR-335 and miR-34a over GC cell growth, apoptosis, and invasion was studied using Cell Counting Kit-8 (CCK-8) assay, flow cytometry, and transwell assay, respectively. Among the GC patients, low miR-335 or miR-34a expression is associated with higher clinical stage and lymph node metastasis. Patients with low miR-335 or miR-34a had poor overall survival, while those with combined low miR-335 and miR-34a expression had even poorer overall survival. miR-335 can directly regulate survivin expression through binding to the 3'UTR, while miR-34a has indirect modulating effect. Both miR-335 and miR-34a could inhibit cell proliferation and invasion and enhance cell apoptosis. But, these effects are largely abrogated by overexpression of survivin without 3'UTR. Therefore, besides the targets identified in previous studies, miR-335 and miR-34a can also regulate GC cell growth, apoptosis, and invasion at least partly through survivin.

The potential disrupting effects of Azo dye on wastewater nutrients removal deserved more analysis. In this study, 15 days exposure experiments were conducted with alizarin yellow R (AYR) as a model dye to determine whether the dye caused adverse effects on biological removal of both the dye and nutrients in acclimated anaerobic–aerobic–anoxic sequencing batch reactors. The results showed that the AYR removal efficiency was, respectively, 85.7% and 66.8% at AYR concentrations of 50 and 200 mg l−1, while higher AYR inlet (400 mg l−1) might inactivate sludge. Lower removal of AYR at 200 mg l−1 of AYR was due to the insufficient support of electron donors in the anaerobic process. However, the decolourized byproducts p-phenylenediamine and 5-aminosalicylic were completely decomposed in following aerobic stage at both 50 and 200 mg l−1 of AYR concentrations. Compared with the absence of AYR, the presence of 200 mg l−1 of AYR decreased the total nitrogen removal efficiency from 82.4 to 41.1%, and chemical oxygen demand (COD) removal efficiency initially decreased to 68.1% and then backed to around 83.4% in the long-term exposure time. It was also found that the inhibition of AYR, nitrogen and COD removal induced by a higher concentration of AYR was due to the increased intracellular reactive oxygen species production, which caused the rise of oxidation–reduction potential value and decreased ammonia monooxygenase and nitrite oxidoreductase activities.

Removal of gaseous chlorobenzene (CB) by a biotrickling filter (BTF) filled with modified ceramics and multi-surface hollow balls during gas–liquid mass transfer at the steady state was by microbial degradation rather than dissolution in the spray liquid or emission into the atmosphere. The BTF was flexible and resistant to the acid environment of the spray liquid, with the caveat that the spray liquid should be replaced once every 6–7 days. The BTF, loaded with Lysinibacillus fusiformis, performed well for purification of high-loading CB gas. The maximum CB gas inlet loading rate, 103 g m−3 h−1, CB elimination capacity, 97 g m−3 h−1, and CB removal efficiency, 97.7 %, were reached at a spray liquid flow rate of 27.6 ml min−1, an initial CB concentration of up to 1,300 mg m−3, and an empty bed retention time of more than 45 s. Electronic supplementary material The online version of this article (doi:10.1007/s10529-014-1559-5) contains supplementary material, which is available to authorized users.

The potential disrupting effects of Azo dye on wastewater nutrients removal deserved more analysis. In this study, 15 days exposure experiments were conducted with alizarin yellow R (AYR) as a model dye to determine whether the dye caused adverse effects on biological removal of both the dye and nutrients in acclimated anaerobic–aerobic–anoxic sequencing batch reactors. The results showed that the AYR removal efficiency was, respectively, 85.7% and 66.8% at AYR concentrations of 50 and 200 mg l −1 , while higher AYR inlet (400 mg l −1 ) might inactivate sludge. Lower removal of AYR at 200 mg l −1 of AYR was due to the insufficient support of electron donors in the anaerobic process. However, the decolorized by-products p -phenylenediamine and 5-aminosalicylic were completely decomposed in the following aerobic stage at both 50 and 200 mg l −1 of AYR concentrations. Compared with the absence of AYR, the presence of 200 mg l −1 of AYR decreased the total nitrogen removal efficiency from 82.4 to 41.1%, and chemical oxygen demand (COD) removal efficiency initially decreased to 68.1% and then returned to around 83.4% in the long-term exposure time. It was also found that the inhibition of AYR, nitrogen and COD removal induced by a higher concentration of AYR was due to the increased intracellular reactive oxygen species production, which caused the rise of oxidation–reduction potential value and decreased ammonia monooxygenase and nitrite oxidoreductase activities.

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Two 90 L anaerobic baffled reactors were used to study the granulation of sludge and the effect of the organic loading rate and NaHCO3/COD ratios on reactor performance. Furthermore, it was determined whether an anaerobic baffled reactor would promote phase separation and if additive of bentonite or granular active carbon was capable of enhancing granule formation. In order to minimize feed variations, and have a totally biodegradable substrate, a synthetic sucrose substrate was used. Granulation was achieved in both reactors within 75 days. However, the granules from the granular active carbon amended reactor appeared earlier and were larger and more compact. The reactors were maintained at a hydraulic retention time of 20 h during performance study stage. The results showed that when organic loading rate were changed from 2.15 to 6.29 kg COD m−3 day−1, chemical oxygen demand (COD) removal was not decreased (91–93%), but a slight increase in effluent COD was observed. It was found that the COD removals were generally good (87–92%) and had not obviously change with the decreasing NaHCO3/COD ratios. From the bacterial distribution and the concentration of volatile fatty acids in four compartments, it was concluded that a separation of phases occurred within the anaerobic baffled reactors.

Activated carbon fibers and multi-surface hollow balls were used to establish biotrickling filter (BTF), and the acclimated sludge was inoculated on surface of packing to purify waste gas containing chlorobenzene. The BTF performance was examined under different conditions in steady state. Results showed that the maximum removal efficiency (RE) could be reached under the condition of chlorobenzene initial concentration of 878.53–1522.48 mg· m-3 and the empty bed retention time (EBRT) of 56 s, while the average removal efficiency was 91.34%. EBRT of 45 s was determined appropriately, and the maximum chlorobenzene removal rate of 102.79 g·m-3·h had been achieved under the condition of chlorobenzene initial concentration of 920.36–2019.85 mg· m-3 and EBRT of 28 s. In the experiment, the BTF system ran stably and had no problem of reactor clogging.