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关键词： Denitrification   DEP removal   MWSB@Fe3O4   Immobilized bioreactor   Sponge-based biocarrier  

摘要： A novel biological carrier combining sponge and modified walnut shell biochar with Fe3O4 (MWSB@Fe3O4) was fabricated to achieve simultaneous removal of nitrate and diethyl phthalate (DEP). The optimal reaction conditions of the immobilized bioreactor were: carbon to nitrogen (C/N) ratio of 1.5, Fe2+ concentration of 20 mg L-1, and hydraulic retention time (HRT) of 8 h. Under the optimal conditions and DEP concentration of 800 mu g L-1, the highest removal efficiency of DEP and nitrate in the immobilized bioreactor with the novel biological carrier were 67.87% and 83.97% (68.43 mu g L-1 h(-1) and 1.71 mg L-1 h(-1)), respectively. Scanning electron microscopy (SEM) showed that the novel biological carrier in this study carried more bio-sediments which is closely related to the denitrification efficiency. The gas chromatography (GC) data showed that the nitrogen production of the immobilized bioreactor (99.85%) was higher than that of another experimental group (97.84%). Fluorescence excitation-emission matrix (EEM) and Fourier transform infrared spectrometer (FTIR) indicated the immobilized bioreactor emerged more extracellular polymeric substances (EPS) which was related to favourable biological stability under the DEP environment. Moreover, according to high-throughput sequencing data, the Zoogloea sp. L2 responsible for iron-reduction and denitrification was the main strain in this immobilized bioreactor.

关键词： Membrane bioreactor   Hydrogen   Dark fermentation   Continuous fermentation strategies   Gas extraction   Hydraulic retention time  

摘要： A liquid/gas membrane bioreactor (L/G MBR) was developed to intensify the dark fermentation process. A hollow fiber membrane module was used to combine biohydrogen production, in situ liquid?gas separation and hydrogen producing bacteria retention in a single unit. The L/G MBR was seeded once and did not require further microbial input, as consistent average hydrogen yield of 0.97 ? 0.09 mol-H2/added mol-glucose and hydrogen production rate of 106.5 ? 10.6 mL-H2/L-medium/h were reached over a year. Different biogas extraction strategies showed that efficient in situ H2 extraction is possible without sweeping gas in the lumen of the fibers, thus facilitating H2 purification in an industrial setting. Modelling predicted an optimal hydrogen yield of 1.2 mol/mol-glucose added for a glucose concentration in the feed of 13.1 g/L, close to experimental hydraulic retention time of 8?10 h with an organic loading rate of 1.4 g-glucose/L-medium/h. No washout of hydrogenproducing bacteria was observed at low HRT (2 h), suggesting the possibility of further hydrogen production rate enhancement using an optimized organic loading rate. Acetate and butyrate were the main metabolites identified. Clostridium and Enterobacter dominated in the liquid outlet. The relative abundance of Clostridium pasteurianum increased with glucose concentration in the bioreactor, as opposed to Clostridium beijerinckii which was more abundant at low glucose concentration. The original hollow fiber L/G MBR configuration enabled the testing and selection of fermentation strategies that greatly simplified the implementation of the dark fermentation process by addressing its key operational bottlenecks. Indeed, the L/G membrane surface served as a support and reservoir for the hydrogen producing bacteria across a wide range of HRT conditions.

关键词： transgenic hairy roots   sprinkle bioreactor   gene expression   anticancer   antimicrobial   antiviral activity  

摘要： Front Cover. Betulinic acid is a pentacyclic triterpene with distinctive pharmacological activities. As reported by Kowalczyk et al. in their full paper at 10.1002/cbdv.202100455 there are differences in the content of betulinic acid and selected anthraquinones in transgenic Senna obtusifolia hairy roots with overexpression of the PgSS1 gene and in transformed hairy roots without this genetic construct. Both hairy root lines grew in 10 L sprinkle bioreactor. The extracts obtained from this plant material were used for biological tests showing a cytotoxic and antiproliferative effect on U-87MG glioblastoma cells and altering the level of apoptotic proteins (Bax, p53, Puma and Noxa). Antimicrobial and antiviral properties were also demonstrated for both tested extracts, with a stronger effect of transgenic hairy root extract.

关键词： 插穗   无性系扩繁   希腊牛至   营养液浓度   基质   生长发育   根系发展  

摘要： 唇形科多年生植物牛至(Origanum vulgare)扦插繁殖的主要技术难题是如何改善牛至根系生长情况和提高壮苗率,本研究以希腊牛至(*** ***)为材料,探究不同营养液浓度和基质配比对其扦插繁殖的影响。结果表明,随着营养液中大量元素浓度的增加,牛至插穗的鲜重、分枝、株高以及总根长、根表面积、根体积、根尖数、毛细根根长和总体积均呈现先增加后降低的趋势,其中0.25×Hoagland营养液效果最佳,与浇灌清水的对照相比,植株鲜重和根体积分别增加了242%和464%。以不同体积配比的泥炭土和蛭石为扦插基质,牛至插穗存活率和各项生长指标也呈现显著差异(P<0.05)。其中,在泥炭土和蛭石体积比为25꞉75的基质中,牛至插穗存活率为100%,插穗生长和根系发育均为各处理最佳。因此,使用泥炭土꞉蛭石(25꞉75)作为扦插基质并每周浇灌0.25×Hoagland营养液是牛至无性系扩繁的适宜条件。

关键词： 膜生物反应器   臭氧工艺   工业区   水处理   应用  

摘要： 以膜生物反应器和臭氧工艺在工业区污水回用处理中的应用为课题进行了深入探讨研究,为工业污水处理和节能减排提供参考。

关键词： 水力停留时间   膜生物反应器   膜污染   溶解性微生物产物   胞外聚合物  

摘要： 为考察水力停留时间(hydraulic retention time,HRT)对膜生物反应器(membrane bioreactor,MBR)体系内的混合液特性和膜污染的影响,对兰州某生活污水处理厂生化尾水进行了浸入式中空纤维MBR现场实验。结果表明,在HRT由6 h逐渐升高至12 h的过程中,胞外聚合物(extracellular polymeric substances,EPS)中大分子质量颗粒物的比例、溶解性微生物产物(soluble microbial products,SMP)的含量和污泥的Zeta电位分布均逐渐增大。同时,EPS多糖含量、污泥粒径和黏度均出现逐渐降低的趋势,这些因素可能共同作用导致膜组件的运行时间缩短、过膜压差(transmembrane pressure,TMP)快速增大,最终致使膜污染进程的加快。在HRT为6 h、膜通量15 L·(m^(2)·h)^(−1)、污泥质量浓度为4000 mg·L^(−1)的条件下,中空纤维式MBR处理生化尾水可以获得较好的混合液特性和处理效果。

关键词： 苯酚高盐废水   萃取膜生物反应器   聚二甲基硅氧烷   相转化膜   跨膜传质  

摘要： 萃取膜生物反应器(EMBR)可将难降解的苯酚高盐废水分离为易降解的低浓度苯酚废水,从而实现苯酚高盐废水的高效降解。针对EMBR中传统硅橡胶管式膜苯酚跨膜传质速率较慢的问题,研究采用相转化法直接制备聚二甲基硅氧烷(PDMS)薄膜,可同时实现苯酚高渗透性与无机盐高截留率。探究了萃取膜生物反应器中废水、微生物单元的流量、pH、温度等参数对苯酚跨膜传质与无机盐截留的影响,优化了EMBR运行条件,并探究了EMBR内微生物的苯酚降解能力及对苯酚跨膜传质的影响。研究发现EMBR最优运行条件:废水单元流量为0.17 L/h、pH值=5.1、温度为34℃;微生物单元流量为0.17 L/h、pH值=5.75、温度为30℃。投加微生物后,该EMBR的苯酚跨膜传质系数最高可达到(4.0~4.3)×10^(-7)m/s,苯酚去除率始终维持在100%,NaCl截留率高于99.9%。研究成果有助于解决EMBR应用推广的瓶颈,对我国水环境污染治理和水资源安全保障有积极意义。

关键词： 生物膜   亚硝化   厌氧氨氧化   DO/NH_(4)^(+)  

摘要： 采用多孔凝胶填料,在低氨氮浓度下接种亚硝化絮体污泥进行填料挂膜,研究了反应器中填料的挂膜过程和不同DO/NH_(4)^(+)下亚硝化效果,采用MiSeq高通量测序技术分析了反应器中微生物种群结构。结果表明:在初始的1~3 d,有大量悬浮絮体污泥进入填料内部,反应器中基本无絮体污泥;随后填料内部的微生物不断由内向外生长,填料表观颜色不断加深,30 d时填料挂膜成功;DO/NH_(4)^(+)比值为0.09~0.2,氨氮容积负荷为1 kg·(m^(3)·d)^(−1)时,亚硝化效果最好,亚硝积累率最高达86.13%。随着DO/NH_(4)^(+)的比值增加,亚硝积累率有所下降。批次实验结果表明,通过控制DO/NH_(4)^(+)的值,能够使生物膜表面形成一层耗氧屏障,则生物膜内部所能利用的氧有限,以此达到抑制NOB的目的。微生物分析结果表明:生物膜中AOB/NOB值为3,AOB在硝化细菌中占主导地位,生物膜中厌氧氨氧化菌得到富集,在34 d时丰度增加至25.13%,符合反应器总氮去除率上升的特征。

关键词： 固定化   多细胞   生物反应器   发酵   膜材料  

摘要： 细胞固定化技术具有高效、反应操作简便、能长时间保持细胞活力且可反复利用、稳定性好、耐受性强等优点,在生物发酵等领域显示出巨大的应用潜力。本文介绍了近年来高分子载体材料、无机载体材料和复合载体材料的细胞固定化技术在生物发酵领域的研究进展,分析了不同材料介导固定化细胞在复杂的环境,如低或高pH、毒性底物和高浓度产物等条件下与游离细胞生长代谢性能差异;并阐述了新型高分子膜材料(中空纤维膜和微米/纳米纤维膜)作为载体在生物发酵中的优势和应用;最后展望了通过设计新型优良聚合物载体来实现人工混菌体系在生物发酵中的可控性和鲁棒性。材料作为生物与非生物中物质界面上的活性和可调成分,为细胞提供了适宜的微环境,在生物发酵领域将得到更广泛应用。

关键词： 生物膜   膜生物反应器   好氧颗粒污泥   生物填料  

摘要： 随着水资源的不断破坏以及人们环保意识的不断增强,研发一种绿色环保的污水处理技术迫在眉睫。目前,生物技术作为绿色环境友好型技术得到了社会广泛认可和应用,而一体化生物膜—膜生物反应器技术是目前污水处理技术中最有发展前景的生物技术之一。因此,本文重点针对一体化生物膜—膜生物反应器技术在污水处理中的机制进行综述分析。