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关键词： Coal gasification wastewater   A   O-MBR   Polyurethane foam   Membrane fouling   Microbial community structure  

摘要： Coal gasification wastewater (CGW) is a typical toxic and refractory industrial wastewater with abundant phenols contained. Two identical anoxic/aerobic membrane bioreactors (with (R2) and without (R1) polyurethane (PU) foam) were carried out in parallel to investigate the role of PU foam addition in enhancing pollutants removal in CGW. Results showed that both systems exhibited effective removal of chemical oxygen demand (>93%) and total phenols (>97%) but poor ammonia nitrogen removal (<35%) constrained by ammonia oxidation process. GC-MS analysis revealed that aromatic and other refractory intermediates were dramatically reduced in R2. Moreover, the PU addition had negligible influence on the total soluble microbial products and extracellular polymeric substances contents but significantly alleviated membrane fouling with the operating time 33% prolonged. Microbial community revealed that Flavobacterium, Holophaga, and Geobacter were enriched on PU. Influent type might be a main driver for microbial community succession. (c) 2021 Published by Elsevier B.V.

关键词： Fe S-based cascade bioreactor   Glucose oxidase   Tumor penetration   Synergistic therapy   ICD amplifier   Cancer immunotherapy   Metastasis inhibition  

摘要： Major challenges for cancer treatment are how to effectively eliminate primary tumor and sufficiently induce immunogenic cell death(ICD)to provoke a robust immune response for metastasis ***,a self-assembled cascade bioreactor was developed to improve cancer treatment with enhanced tumor penetration and synergistic therapy of starvation,chemodynamic(CDT)and photothermal *** Fe S-GOx nanodots were synthesized with glucose oxidase(GOx)as template and induced by paclitaxel(PTX)to form self-assembling Fe S-GOx@PTX(FGP)via hydrophobic *** accumulated at tumor sites,FGP disassembles to smaller Fe S-GOx for enhanced deep tumor *** maintains high enzymatic activity to catalyze glucose with assistant of oxygen to generate hydrogen peroxide(H2O2)as starvation *** reaction involving the regenerated H_(2)O_(2) in turn produced more hydroxyl radicals for enhanced *** near-infrared laser at 808 nm,FGPs displayed pronounced tumor inhibition in vitro and in vivo by the combination *** consequent increased exposure to calreticulin amplified ICD and promoted dendritic cells *** combination with anti-CTLA4 checkpoint blockade,FGP can absolutely eliminate primary tumor and avidly inhibit distant tumors due to the enhanced intratumoral infiltration of cytotoxic T *** work presents a promising strategy for primary tumor and metastasis inhibition.

关键词： 何首乌   Polygonum multiflorum   扦插   正交试验   成活率   根系效果指数  

摘要： 通过正交试验,研究不同扦插枝条、不同生根剂及其浓度、基质对何首乌(Polygonum multiflorum)扦插成活及扦插苗生长的影响。结果表明,影响何首乌扦插成活率的主要因素是扦插枝条和基质;以扦插成活率和根系效果指数作为综合评价指标,何首乌扦插最适扦插组合为采用半木质化枝条,基质采用河沙∶壤土=1∶2。

关键词： E-waste   Bubble column bioreactor   Acidithiobacillus ferrooxidans   Basis metal recovery   Optimization  

摘要： The high amount of base metals poses an important challenge in gold bioleaching from spent printed circuit boards (PCBs). This study aims to investigate the bioleaching of important base metals (Cu, Ni, and Fe) from a mixture of spent PCBs (E-waste) using adapted Acidithiobacillus ferrooxidans in the bubble column bioreactors. Firstly, the adaptation process is done from 1 to 15 g/L in Erlenmeyer flasks in 187 days, then the concentration of E-waste increased to 40 g/L in bubble column bioreactors in 44 days. The concurrent recovery of copper, nickel, and iron using adapted bacterium in a bioreactor was optimized by central composite design. Various effective parameters such as aeration rate, initial ferrous sulfate concentration, and solid waste loading that significantly affected bioleaching yields were studied. 54% of Cu (6% dissolution/d), 75% of Ni (8% dissolution/ d), and 55% of Fe (6.1% dissolution/d) were simultaneously recovered under the optimum condition of 20 g/L of solid content, 1.5 vvm of aeration rate, and 40 g/L of the initial concentration of ferrous sulfate after only 9 days. The results proved 100% recovery of each metal is separately possible;100% of Cu and Fe are extracted maximally on the 4th and 13th day, respectively. Ni is recovered maximally 96% on the 17th day. This is the first report of an ecofriendly method for the bioleaching of important base metals from E-waste in a bubble column bioreactor. Thus, the obtained results contribute to the knowledge of microbial hydrometallurgy on a large scale.

关键词： Anaerobic membrane bioreactor   Flat-sheet ceramic membrane   Extracellular polymeric substances (EPS)   Soluble microbial products (SMP)   Membrane cleaning  

摘要： In this study, the feasibility of an anaerobic flat-sheet ceramic membrane reactor for sewage treatment was evaluated, and the membrane fouling mechanism and membrane cleaning methods were studied. The results showed that when the transmembrane pressure was greater than 35 kPa, the hydraulic retention time and temperature affected the membrane fouling by causing the microbial metabolism to produce extracellular polymeric substances and soluble microbial products. In addition, the surfaces of the initial, polluted, and cleaned membranes were analyzed using scanning electron microscopy, and the fouling mechanism of the flat-sheet ceramic membrane was analyzed. With the combination of physical and chemical cleaning, most pollutants on the membrane surface and pores were removed;however, a small amount of pollutants remained in the pores. The results showed that the cleaning methods were effective in controlling membrane fouling.

关键词： 膜生物反应器:污水处理   工作原理  

摘要： 膜生物反应器(Membrane Bio-Reactor,MBR)是一种由膜分离单元与生物单元相结合的新型水处理技术,被广泛应用于污水处理,水资源再利用领域。与传统的污水处理技术相比较,MBR技术更加高效,而且污水的处理效果更好,能够实现自动化。文章主要对膜生物反应器的原理、类型及工艺特点等方面进行探讨,对其在实际运用中膜污染产生的机理展开分析并提出解决措施,对新型膜生物反应器及其工艺改进方法进行详细介绍,为进一步优化膜生物反应器提供参考。

关键词： 陶瓷膜   污水治理   脱氮   农村用水  

摘要： 基于我国农村农户居住分散的特点,采用低投资、能耗少、操作管理要求低的分散式污水处理技术处理农村污水较为适宜。文章通过对相关领域的研究成果及进展进行研究分析,以此为基础视角,从膜生物技术应用角度展开,分析了膜生物技术处理污水的技术原理,进而围绕已有膜生物技术对于各方面污水处理应用进行综合探讨,分析陶瓷膜在污水治理方面的技术可行性、策略研究性、生态性、优越性等。

关键词： Azolla filiculoides   batch reactor   continuous reactor   dairy wastewater   removal  

摘要： Fast and proper treatment of dairy wastewater is necessary before discharging it to the environment. In this study, healthy Azolla filiculoides was used to remove pollutants, including phosphorus (P), sodium (Na), chemical oxygen demand (COD), biological oxygen demand (BOD), and total dissolved solids (TDS) of dairy effluent in batch, continuous system, as well as continuous with the slow stirring system. These systems were handmade. The maximum removal efficiency was related to the P, which obtained 66.25% after 12 h in the batch bioreactor system. The highest removal of 13.69% after 21 h was obtained for Na using continuous with a slow stirring method. The highest removal related to the COD and BOD was 33.53% and 29.93% after 18 h, respectively, in continuous with the slow stirring system. TDS removal was achieved 31.44% after 24 h using the batch system. The results of these three systems were compared with each other using a one-way analysis of variance (ANOVA). There was no significant difference between them. Azolla filiculoides is an abundant plant in northern nature that a biosystem was used for optimum usage. It can be used as an efficient, inexpensive, and affordable bioadsorbent for dairy wastewater treatment. Practitioner points Live Azolla filiculoides was used to remove pollutants. P, Na, BOD, COD, and TDS were removed from dairy wastewater. Batch, continuous, and continuous with the slow stirring systems were used. Live Azolla was an efficient, inexpensive, and affordable bio-adsorbent for dairy wastewater treatment.

关键词： Biohydrogen production   Baffled bioreactor   Hydraulic retention time   Dilution ratio   Electron balance  

摘要： This work studied the sequential hydrogen production by dark and photo-fermentation (HPDPF) in continuous baffled bioreactors. Taken enzymatic hydrolysate of corn stover as initial carbon source, the influence of hydraulic retention time (HRT) of dark fermentation (DF) and the dilution ratio (DR) of dark fermentation effluents (DFEs) on the hydrogen production performance of the combined fermentation system and electron distribution were investigated. For DF unit, the highest hydrogen production rate (HPR) of 5.24 L/(L center dot d) was detected at HRT of 18 h, however, the maximum HPR of 4.60 L/(L center dot d) was obtained from DFEs with HRT of 12 h and DR of 1:0.5 during photo fermentation unit, meanwhile, the electrons in substrate partitioning to H2 reached the maximum value of 35.69%. In terms of hydrogen yield, the optimum operating conditions of the combined system were HRT of 12 h (DF) and DR of 1:0.5(DFEs), in which the hydrogen yield reached 12.73 L/d.

关键词： Nitrogen removal   Ferrous sulfide   Autotrophic denitrification   Anammox   Fluidized bed bioreactor  

摘要： On the basis of the metabolic synergy between autotrophic denitrification (AuDen) and anaerobic ammonium oxidation (Anammox), the feasibility of a novel ferrous sulfide (FeS)-driven AuDen and Anammox coupled system (FS-DADAS) was investigated. The nitrogen removal performance of FS-DADAS was investigated in a labscale fluidized bed bioreactor fed with synthetic wastewater containing NH4+-N and NO3--N. The results of long-term operation (120 days) demonstrated the promising performance of the system with 100% NO3--N removal and NH4+-N concentrations lower than 8.11 mg L-1 in the effluent at a nitrogen loading rate of 0.20 g-N.(L.d)(-1). Sufficient NOi-N was provided by the AuDen for Anammox where a high removal rate of total nitrogen (TN) was achieved. The contribution of Anammox to TN removal was at >80%. The reactor could maintain a stable pH with less SO42- production owing to the fact that Fe(II) and S acted as electron donors. FeS gradually transformed into a sheet-like secondary mineral, FeOOH. AuDen (Thiobacillus) and Anammox bacteria (Candidatus Kuenenia) were successfully retained in the bioreactor, with relative abundance values of 18.82%-23.64% and 3.52%-8.67%, respectively. FS-DADAS is a promising technology for the complete removal of TN from wastewaters with low C/N ratios at low energy consumption.