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关键词： 厌氧氨氧化   短程硝化   基质浓度   固碳能力   微生物种群   废水处理  

摘要： 采用分体式厌氧氨氧化反应装置,以短程硝化-厌氧氨氧化工艺为研究对象,通过改变基质浓度探究其对工艺固碳潜力的影响,寻找最佳固碳量的运行工况;通过收集反应器运行各阶段的污泥样品,对其中的微生物种群多样性进行分析,确定工艺的固碳微生物。试验结果表明:确定进水中NH^+_4-N浓度为180 mg/L时,工艺展现出最佳的固碳能力;短程硝化阶段,当进水中NLR为0.44 kg-N/(m^3·d^(-1))、HRT为10 h时,固碳量为0.285 mg/mg-N;厌氧氨氧化阶段,当进水中NH^+_4-N和NO^-_2-N浓度分别为75 mg/L、95 mg/L,HRT为24 h、NLR为0.13 kg-N/(m^3·d^(-1))时,固碳量为0.16 mg/mg-N。微生物种群多样性分析表明:短程硝化反应器中的优势菌种为Acidobacteria Bacteria(酸杆菌)、Chlorobi(绿菌)、Proteobacteria Bacteria(变形杆菌);厌氧氨氧化反应器中的优势菌种为Planctomycete Bacteria(浮霉菌)、Actinobacteria Bacteria(放线菌)、Proteobacteria Bacteria(变形杆菌)。

关键词： IBA   基质   迷迭香   扦插生根  

摘要： 用50 mg/L IBA、100 mg/L IBA、300 mg/L IBA浸泡迷迭香嫩枝插穗、半木质化插穗、完全木质化插穗30min后,扦插在沙子及混合基质中,均促进生根,成活率83%～100%,其中100mg/L IBA促进迷迭香插穗在沙子里及混合基质里生根效果最好,不同部位枝条插穗生根总体效果:半木质化枝条>嫩枝>完全木质化枝条。

关键词： 家蚕   转基因   基因编辑   生物反应器  

摘要： 自家蚕基因组测序完成以来,家蚕的相关研究进入了后基因组时代,也使得家蚕的转基因技术得以迅速的发展。文章介绍了家蚕中转基因的技术及其发展现状,为今后的基因编辑技术、转基因家蚕研究以及生物反应器等应用提供了借鉴与参考。

关键词： 生物反应器   选型原则   设备选型   新发展  

摘要： 近几年,随着生物工业的发展,生物反应器工程也获得了显著的提高,生物反应器向着大型化、自动化发展,新型生物反应器得以涌现和发展,出现了一些新的变化。论述了国内外生物反应器发展的特点、选用原则,包括嫌气发酵生物反应器选用、通风发酵生物反应器选用、固态发酵生物反应器选用、酶生物反应器选用、动物细胞培养生物反应器选用、植物细胞培养生物反应器选用等,并对其未来发展趋势进行了展望。

关键词： Solid-state fermentation   Bioreactor   Scale-up   Mathematical modelling   Bioethanol  

摘要： Mathematical models can be useful to predict the behavior of particulate systems, as it is the case of packed-bed bioreactors (PBBs) used for solid-state fermentation (SSF). The models also simplify the processes scale-up, and depending on the accuracy of the model, critical parameters can be predicted, as temperature, moisture content and maximum bed height. In the current paper, mathematical models and simulations were used to predict the optimal conditions for enzymes production by means of SSF in PBBs. Two models available in literature were applied: a recently proposed two-phase and two-dimensional (2-D) model and a modified Damkohler number (Da(m)) approach, considering maximum temperatures of the bed and maximum bed height to allow good production of enzymatic activities by the fungus Myceliophtora thermophila I-1D3b. Based on simulation results, experiments in bench and pilot-scale PBBs were performed and analyzed. By comparing experimental and simulated results of temperatures, the 2-D model showed to be more accurate than Da(m) approach. Despite of the temperature increase in pilot-scale PBB, the bioreactor scale-up with the fungus M. thermophila in substrate composed of sugarcane bagasse (SCB) and wheat bran (WB) (weight proportion 7: 3) could be considered as feasible for cellulolytic and xylanolytic enzymes provision, for instance, for second generation ethanol production chain, although issues related to airflow distribution and substrate shrinkage in pilot-scale PBB must still be further overcome.

关键词： 肝衰竭   人工肝   生物人工肝   肝细胞   生物反应器  

摘要： 肝衰竭是临床常见的严重肝病症候群,病死率极高,除肝移植外,目前尚无有效的治疗方法。人工肝支持系统是治疗肝功能衰竭的重要方法之一,主要包括非生物型人工肝和生物型人工肝。结合了功能性肝细胞的生物型人工肝装置可发挥肝脏解毒、合成、代谢等功能,并且可以部分替代人体肝脏功能。生物型人工肝研发的关键在于种子细胞的筛选和生物反应器的构建。具有良好特性种子细胞的生物人工肝对于肝衰竭的疗效已在一些临床前研究中得以体现,并且目前已启动了多个生物人工肝的临床研究。该文从种子细胞的来源、生物反应器结构分类和临床应用等不同方面,对目前生物型人工肝的发展现状进行了综述。

关键词： Current density   Electrochemical chlorination   Fouling   Membrane bioreactor  

摘要： We interrogated the effects of in-situ electrochemical chlorination with Ti/IrO2 anodes on physicochemical properties of mixed liquor and fouling in membrane bioreactors (MBRs). Linear sweep voltammetry with variable concentrations of model organic foulant (alginic acid) indicated negligible direct oxidation. Batch electrolysis under current densities (j) up to 1.2 mA/cm(2) further indicated that free chlorine (FC) primarily mediates transformation of dissolved compounds such as NH4+-N and organic carbon (DOC) including protein and soluble microbial product (SMP, as noted in excitation-emission matrix, EEM). Owing to infinitesimal steady-state concentrations of FC under electrolytic generation, diffusion of FC determined the transformation kinetics in bulk, while floc/cell breakage and mineralization of extracellular polymeric substances (EPS) were marginal. Decay of negatively charged functionalities was found to compete with carbonyl generation on aromatic carbons (noted by red shift of EEM peak), which determined the magnitude of floc zeta-potential. A cathodic scale deposition was presumed to bring about PO43- removal and stimulate sludge flocculation. This study evinced that an increased floc size coupled with removal and/or transformation of hydrophobic DOC would contribute to the alleviated membrane fouling. However, significant decreases in microbial utilization rates of DOC under exposure to j > 0.8 mA/cm(2) accelerated fouling during continuous operations of MBRs. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： 音圈直线电机   脉动生物反应器   STM32   H桥驱动电路  

摘要： 脉动生物反应器能够模拟在体心脏瓣膜的流体力学特征,产生搏动性液体,为组织工程心脏瓣膜提供良好的体外培养环境,使得组织工程心脏瓣膜的表皮细胞在植入人体后能够经受人体内高速血流的冲击,不易脱落。为了实现模拟心脏搏动的功能,脉动生物反应器采用音圈直线电机作为系统的动力源,并以STM32微控制器、PWM驱动电路、H桥驱动电路和触摸屏等构成驱动控制系统。经过实际测试,该动力系统响应迅速、运行稳定,能够产生满足人体血流环境的流量和压力差。该驱动控制系统机械结构简单无中间转换机构有利于系统集成化,使用中噪声小,为脉动生物反应器提供临床应用从技术上铺平道路。

关键词： Bio-hydrogen   Granular sludge   Membrane bioreactor   Organic loading rate   Hydraulic retention time  

摘要： Biohydrogen was produced using a granular biomass reactor coupled to a submerged internal membrane. The reactor performance was evaluated under different organic loading rates (OLR) ranging from 5 to 60 g L-1 d(-1) and hydraulic retention times (HRT) from 5.5 to 1.25 h. The UASB reactor was operated at 35 degrees C and pH 4.5. It was observed that the membrane introduction to the reactor does not affect the granule size or integrity. The maximum hydrogen production rate was obtained at 30 g L-1 d(-1) and 4 h of HRT (475 +/- 15 mLH(2) L-1 h(-1)). A further increase of the OLR resulted in a lower hydrogen production due to a shift of the metabolism to solvent production. The use of membranes allowed the application of relatively low HRT;however, HRT lower than 2 h promoted the homoacetogenic metabolism, decreasing the hydrogen production. The results indicate that the membrane fouling is not only affected by the total EPS formed but also by the operational flux applied.

关键词： 猪瘟病毒   低血清反应器灌流培养   ST细胞   免疫效价  

摘要： 目的利用生物反应器低血清培养基灌流培养猪瘟病毒,制备猪瘟病毒活疫苗,检测其免疫效价。方法对猪睾丸ST细胞进行低血清培养驯化,待ST细胞适应低血清培养后,接种至生物反应器,当细胞达到接种密度后,感染猪瘟兔化弱毒株(Classical Swine)毒种,培养96 h后,连续收液48 d,收获的病毒液经滤膜过滤后,制备猪瘟病毒活疫苗。将疫苗免疫健康新西兰家兔和28日龄健康仔猪,检测病毒滴度及免疫效价。结果用2%血清培养ST细胞,细胞接毒密度为5×106个/m L,病毒按3%~5%比例接种。利用上述条件培养的猪瘟病毒连续收获20次,病毒滴度均在7 500 RID/m L以上。免疫仔猪后第14天抗体效价达1∶128,未免疫仔猪抗体效价低于1∶16;攻毒后观察16 d,免疫仔猪无任何猪瘟临床表现,保护率100%,而未免疫仔猪在攻毒后第6天开始陆续死亡,死亡率100%。结论用低血清培养ST细胞制备的猪瘟病毒活疫苗具有较高的免疫效价,为猪瘟病毒疫苗生产工艺的改进奠定了基础。