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关键词： 膜生物反应器   垃圾渗滤液   膜污染   脱氮除磷  

摘要： 采用间歇曝气的序批式膜生物反应器(SMBR),在HRT为2 d、排泥条件下(SRT为30 d)运行,对TN的质量浓度低于2 g/L的渗滤液进行处理,并与连续曝气的普通MBR进行对比。结果表明,2种反应器可将垃圾渗滤液COD降至0.32~1.2 g/L;SMBR对NH_4^+-N与TN的去除率可分别达到77.1%和72.3%,对TN的去除效果远好于MBR的48.6%。间歇曝气的SMBR膜的污染速度相对MBR较慢,采用反冲洗+酸洗+碱洗+氧化剂的清洗方式可有效降低过膜压力;计算表明有机污染是膜污染的主要原因。投加粉末活性炭的SMBR减缓了膜的污染速率,其运行周期从32 d延长至44 d。

关键词： 厌氧   陶瓷膜   模拟生活污水   运行效能   膜污染  

摘要： 为强化厌氧系统的处理效能,延缓厌氧膜生物反应器膜污染速率,采用分置式厌氧陶瓷膜生物反应器处理模拟生活污水.结果表明:厌氧反应器UASB经过60 d的启动,可实现对模拟生活污水的良好处理,COD去除率超过90%;耦合膜组件运行后,膜出水COD在22.58 mg·L^(-1)左右,COD总去除率平均为95.53%,甲烷日均产量为352 mL·d^(-1),产率最高达到0.11 m^3·kg^(-1);跨膜压差(TMP)达到26.81 kPa时膜污染严重,周期为14 d,反冲洗能够去除膜表面的泥饼层,有效地延长膜污染周期;对混合液及滤饼层中的多糖和蛋白质浓度进行了分析,结果表明,蛋白质是引起膜污染的主要物质.

关键词： 混合生长式膜生物反应器   填料   导流板   隔离网   流体力学特性  

摘要： 在中试规模的混合生长式膜生物反应器(HG-MBR)中,采用导流板对膜区和填料区的隔离网进行了优化研究,通过清水试验分析了导流板面积和位置对反应器流体力学特性的影响。结果表明,使用导流板可以改善反应器的流体力学特性,减小隔离网对填料流动的负面效应,降低驱动填料流化所需的曝气量,促进填料在反应器内的循环流动,从而达到节能降耗的目的。优化运行结果表明,膜区和填料区之间的隔离网在上部采用导流板式封闭设计(面积约为0. 71 m^2),当填料填充率为50%时,驱动填料流动所需的曝气量可减少15%以上,节能效果明显。

关键词： 转基因动植物   生物反应器   药用蛋白   产业化   应用  

摘要： 转基因动植物作为生物反应器,有完善的真核表达系统,可以为多种外源蛋白提供正确的翻译后修饰,表达具有生物活性的外源蛋白,可以应用于人或动物的疾病治疗及预防,因其具有成本低、产出高、产品珍贵且需求高的特点而具有广阔的商业前景。目前,转基因动植物生物反应器研究领域已经取得多项成果与突破,以此生产的蛋白制品也有部分被权威机构批准上市应用,还有许多未上市的研究成果已经进入临床试验阶段,为产业化发展做准备。动植物生物反应器已成为重组药用蛋白生产的新趋势。综述了转基因植物和转基因动物作为生物反应器生产重组蛋白的研究进展及应用现状,介绍了生物反应器类型、生产的蛋白种类、已获批应用的动植物生物反应器,讨论了利用动植物生物反应器生产外源蛋白的意义及存在的问题,对其研究及应用前景进行展望。

关键词： 膜生物反应器   污泥   厌氧消化   污泥混合液   膜污染  

摘要： 结合厌氧消化和膜分离特点的厌氧膜生物反应器(AnMBR)应用于污泥处理,形成可提高污泥厌氧消化效率的污泥AnMBR。污泥AnMBR是目前污泥厌氧消化的重要研究方向,对污泥AnMBR的发展、研究和应用现状进行总结,分析了污泥AnMBR的膜污染及其影响因素,重点讨论了污泥混合液对污泥AnMBR膜污染的影响,并对污泥AnMBR下一步研究进行了展望。

关键词： Dendrogram   Geneious software   Mean population   Phylogenetic analyses   Shannon-Wiener index  

摘要： Nitrite is a well-known toxicant in aquaculture, produced as intermediate in nitrification. Two nitrite-oxidizing bacterial consortia, one from marine environment and the other from brackish water, were developed by enrichment technique at National Centre for Aquatic Animal Health, for removal of nitrite from recirculating aquaculture systems. In the present study, bacterial diversity of the consortia was assessed based on 16S ribosomal RNA and the functional gene analysis. Clone libraries of 16S ribosomal RNA gene and nitrite oxidoreductase A gene were constructed, and amplified ribosomal DNA restriction analysis was carried out to cluster the clones. Dendrograms generated through molecular characterization showed 29 and 27 clusters in marine and brackish water consortia, respectively. Phylogenetic analyses of representative clones from each cluster depicted profound diversity in the consortia consisting autotrophic nitrifiers belonging to Proteobacteria, anaerobic ammonia oxidizers, Actinobacteria, Bacteroidetes and heterotrophic denitrifiers. Functional gene analysis corroborated with the presence of specific nitrite oxidizers. Quantitative polymerase chain reaction showed the abundance of nitrite oxidizers in the order of 1.51 +/- 0.38 x 10(9)/g and 4.88 +/- 0.42 x 10(7)/g in marine and brackish water consortia, respectively. Diversity indices and pattern of distribution of organisms within the consortia were analyzed using Geneious, VITCOMIC, Mega 5 and Primer software. The marine nitriteoxidizing consortium showed higher Shannon-Wiener diversity and mean population diversity than brackish water consortium, suggesting that the former was having more diverse flora and higher potential to be used as startup cultures for activating nitrifying bioreactors subsequent to acclimatization to the required salinity.

关键词： Membrane fouling   interfacial interactions   XDLVO theory   Membrane bioreactor   Surface morphology  

摘要： While governing adhesion/deposition of various foulants on membrane surface and membrane fouling in membrane bioreactors (MBRs), interfacial interactions with real membrane surface have not yet been fully quantified. In this study, theoretical deduction and experiments were carried out to numerically elucidate interfacial interactions in a MBR. A continuous real membrane morphology was reconstructed based on atomic force microscopy (AFM) characterization and triangulation technique. Thereafter, a method to calculate those interactions was established by incorporating the spatial relationship between a foulant and the reconstructed morphology into surface element integration (SEI) method. A case study of the proposed method was conducted. With surface characterization of the foulants and membrane, the interfacial interactions with real membrane morphology were approximated for the first time by computer programming according to composite Simpson's rule. The results showed that rough morphology prolonged the interfacial interactions, indicating the profound role of morphology in the interfacial interactions related with membrane fouling. The new method would provide significant in-sights into membrane fouling in MBRs. (C) 2018 Elsevier Ltd. All rights reserved.

关键词： Parachlorella kessleri   Nutrient dilution   150-L mass cultivation   Whole genome sequencing   Mutation identification   Single-nucleotide polymorphism  

摘要： Parachlorella kessleri (formerly Chlorella kessleri) can accumulate high levels of both starch and lipids that can be used for the production of bioethanol and biodiesel, respectively. We mutagenized P. kessleri by heavy-ion beam irradiation and obtained a biotechnologically promising mutant strain, PK4, for further improvement of lipid productivity in comparison with wild type [1]. PK4 reached two times the optical density and accumulated 2.6 times as much starch in complete urea-phosphate (UP) media compared to Iris-acetate-phosphate (TAP) media under laboratory conditions. Similarly to wild type, PK4 accumulated only negligible amounts of lipids in complete UP media. PK4 accumulated more lipids (WT: 1.17 g L-1, PK4: 1.75 g L-1) and accumulated lipids faster than WT after dilution of the UP media (WT;0.22 g L-1 day(-1), PK4;0.43 g L-1 day(-1)). The productivity of PK4 was analyzed in mass culture using a 150-L thin-layer photo bioreactor housed in a temperature and ligh-tuncontrolled glass greenhouse. The PBR consisted of two glass plates (each 6 m long and 1 m wide) at an inclination of 1.6%, arranged in a meandering path and connected with a trough. The culture was diluted four-fold with water on day 7 post-inoculation to ensure prompt nutrient limitation in the UP media. Lipid accumulation in PK4 was significantly induced so that it accumulated 66% of lipid per dry weight. Under 150-L mass cultivation conditions, PK4 showed high biomass productivity (0.82 g L-1 day(-1)) and high lipid productivity (0.59 g L-1 day(-1)). In addition, the whole genome of PK4 was sequenced to clarify the genetic variation upon heavy-ion-beam irradiation by comparison with the reference genome of WT. As a result, genetic differentiation of PK4 was found at three genes encoding endo-1,4-beta-mannanase, an ATP/ADP transporter, and an elicitor response protein.

关键词： the body as a bioreactor   prefabrication   gastrocolic omentum   bone engineering   CAD/CAM  

摘要： In 2016, we reported the world's first reconstruction of a mandibular discontinuity defect using a custom-made bone transplant that had been prefabricated in the gastrocolic omentum using tissue engineering strategies. However, the tissue of an engineered human neomandible has not been evaluated histologically until now. The current study assessed the long-term histological characteristics of biopsies of the neomandible 9 months after transplantation. Histological analysis showed an increased amount of vital mineralized bone tissue after 10 months, in comparison to biopsies obtained earlier. The engineered bone covered the surface of the bone substitute material but also grew out typical structures of cancellous bone tissue without a core of BioOss. The amount of induced bone tissue was 32% in the biopsy. In addition, the soft tissue showed an alignment of the connective tissue fibres parallel to the trabecular bone. Increasing time and mechanical forces at the mandible led to an increased amount of mineralized tissue and remodelling of the connective tissue fibres after transplantation. Further research should focus on developing advanced scaffold materials, as the outer titanium mesh cage leads to complications.

关键词： Bioleaching   Bioreactor   Iron oxidation   Biocatalytic threshold   Cell concentration  

摘要： Microbial oxidation of ferrous to ferric iron allows efficient oxidative processing of sulfide minerals under ambient conditions. This study determined the effect of cell concentration of a mixed mesophilic microbial culture on iron oxidation rate, and evaluated if there was a cell concentration threshold that dictates a maximal volumetric iron oxidation rate. A bioreactor with feedback-loading of ferrous media was operated at 30 degrees C to maintain a redox potential of + 480 mV vs. Ag/AgCl at pH of 1.3. A positive and linear correlation (R-2 = 0.955) between the cell concentration (6.8 x 10(7)-7.1 x 10(9) cells mL(-1).) and volumetric biological iron oxidation (up to 6.9 g L-1 h(-1)) was observed. The specific iron oxidation was not affected by cell concentration, and no biocatalytic threshold was observed. This indicated that a high cell concentration can be used to achieve a high volumetric iron oxidation rate, enabling the use of a compact reactor size.