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关键词： Alkaline protease   Aspergillus tamarii   response surface methodology   stirred tank bioreactor  

摘要： Proteolytic enzymes are one of the significant commercially manufactured enzymes. The manufacture of extracellular alkaline protease byAspergillus tamariiMTCC5152 was explored using several agricultural by-products as substrates viz., cottonseed meal, wheat bran, skimmed milk and soya flour in submerged fermentation, were found to be efficient for enzyme production and commercially significant. Response surface methodology (RSM) is a statistics-based experimental design, sourced to explore the impact of physical parameters on the manufacture of protease fromA. tamariiin a batch stirred tank bioreactor (STBR). The four substantial variables (pH, temperature, inoculum size, and agitation) were carefully chosen for optimization analyses and the statistical pattern was created using a central composite design and the quadratic model has been developed. The optimum conditions for protease production (1.51 U mL(-1)) where: pH 6.4, temperature 27 degrees C, inoculum size 2.6%, and agitation 327 rpm. The analysis revealed that the anticipated values were in accord with trial data with a correlation coefficient of 0.969.

关键词： 生物反应器   搅拌速度   计算流体力学模拟   CHO细胞   悬浮培养  

摘要： 目的考察搅拌式生物反应器不同搅拌速度对悬浮培养的CHO细胞生长、代谢及促卵泡激素(follicle stimulating hormone,FSH)表达的影响。方法采用计算流体力学(computational fluid dynamics,CFD)技术对5 L生物反应器在100、200、300、400 r/min搅拌速度下的内部流场进行模拟;对培养过程中的细胞密度、细胞活率、细胞直径、pH、生化参数及FSH浓度进行检测,根据细胞比生长速率、葡萄糖比消耗速率、谷氨酰胺比消耗速率、乳酸比生成速率、氨比生成速率以及FSH浓度变化,确定不同搅拌速度对细胞生长、代谢及FSH产量的影响。结果在100、200、300、400 r/min搅拌速度下,随着搅拌速度的增加,反应器内的剪切速率逐渐增大;导致最大细胞密度逐渐降低,依次为6.22×10^6、6.14×10^6、5.87×10^6、5.72×10^6个/mL;细胞比生长速率逐渐降低,依次为0.52、0.49、0.47、0.47/d;培养前5 d,在100 r/min搅拌速度下,较其他条件下细胞代谢变慢,培养后5 d无明显差异;搅拌速度对FSH产量无显著影响。结论本研究从微观角度了解了反应器内的流场特性,将仿真与实验结合,确定了不同搅拌速度下产生的剪切力对CHO细胞悬浮培养的影响,为细胞培养工艺参数的优化奠定了基础。

关键词： 微型生物反应器   平行生物反应器   高通量技术   生物医药  

摘要： 微小型生物反应器体积微小但在线分析检测和过程控制功能媲美台式装备。其核心支撑技术包括一次性材料及微加工技术、非接触式光学传感器、自动化以及实验设计(DOE)、数据分析软件与过程控制的整合。由于体积微小、湍流程度和单位能耗较低,微小型反应器内的混合、传质、剪切特性与工业规模设备有一定的区别。现阶段微小型生物反应器主要用于菌株和细胞系筛选和工艺优化,在实现高通量工艺的同时确保了数据的丰度,对缩短研发周期和加速产品上市,尤其是在应对突发性传染性疾病方面有着重要的意义。未来,精准医疗概念的落实也依赖功能柔性化的微小型生物反应器系统。

关键词： Leachate effluent from a membrane bioreactor   Microwave irradiation   Persulfate   Hydrogen peroxide   Refractory organic substances  

摘要： This study systematically compared the effect of microwave irradiation activated persulfate (MW/PS) and hydrogen peroxide (MW/H2O2) on organic matter removal in mature landfill leachate effluent from a membrane bioreactor (MBR), the reactive oxygen species (ROS) produced, and the degradation and transformation mechanisms of organic substances. An obvious synergistic effect was identified in the MW/PS and MW/H2O2 processes. The synergistic effect of the MW and PS (synergy coefficient F = 23.67) was significantly higher than that of the MW and H2O2 (synergy coefficient F = 11.43). The MW/PS process had a stronger degradation effect on organic substances than the MW/H2O2 process, even when the PS dosage was significantly lower than the H2O2 dosage. The removal rate and k(obs) (initial reaction rate) of the two processes could be raised by increasing the oxidant dosage. Increasing the MW output power improved the removal rate of organics by the two processes, but an excessive MW output power only improved the k(obs) of the two processes, while the effect on organic matter removal was not significant. The MW/H2O2 process only removed organics expeditiously under acidic conditions, while the MW/PS process resulted in a strong degradation of organic matter under a wide range of pH values. A quenching experiment using alcohols indicated that both SO4 center dot- and (OH)-O-center dot existed in the MW/ PS process, with SO4 center dot- playing a leading role in the degradation of organics, while (OH)-O-center dot played a leading role in the MW/H2O2 process. A spectrum analysis based on the quenching experiment demonstrated that the two processes destroyed the characteristic structure of humus and refractory organics in the leachate (i.e., humic acid-like (HAL) and fulvic acid-like (FAL) substances), mainly through the free radical oxidation mechanism. The SO4 center dot- degraded HAL substances efficiently, while (OH)-O-center dot had a better degradation effect on FAL subs

关键词： 大熊猫犬瘟热   微载体悬浮培养   生物反应器  

摘要： 根据正交试验对大熊猫犬瘟热病毒(CDV-PA-1421株)在生物反应器中的培养工艺进行优化,确定关键技术参数。结果表明,大熊猫犬瘟热病毒悬浮培养最佳组合条件为:Vero细胞长成单层后,接种到生物反应器,细胞接种浓度为0.2×10^6/mL^0.4×10^6/mL,微载体浓度为8.0 g/L,加入MSVP培养基至工作体积。按0.01~0.1感染复数(MOI)接种病毒,在37℃pH7.2条件下培养96~120 h,细胞病变(CPE)达70%~80%时收获病毒上清液,即可获得高滴度病毒液。3批培养结果显示病毒培养工艺稳定,收获液病毒含量均在10^7.0~10^7.5 TCID50/0.1mL之间。

关键词： 营养液   基质栽培   阳台生菜   长势   影响  

摘要： 试验以常见的阳台蔬菜种类——生菜作为研究对象,考察不同用量的日本园试营养液对生菜阳台基质栽培的影响,考察指标包括株高、茎粗。研究结果表明,在1/6~1/2浓度范围内,营养液浓度的提高有助于生菜的生长,株高、茎粗均随营养液浓度的增加而增加,且1/2浓度处理的生菜长势最好。

关键词： 厌氧膜生物反应器   有机物转化   水处理新技术   能源回收   有机负荷   产甲烷菌   资源回收   全球可持续发展  

摘要： 水资源短缺与能源危机是人类繁荣发展面临的重大挑战。"以能耗换水质"的传统污水处理技术已无法满足全球可持续发展的需求。开发以"能源再生-资源回收"为目标的新技术成为污水处理革新的新趋势[1]。污水中所蕴含的潜能可达污水好氧生物处理所需能耗近10倍[2]。通过厌氧生物技术将污水有机物转化为甲烷能源是目前普遍认可的实现污水处理能量收支平衡的重要方法。然而,传统厌氧技术受制于污泥流失量大、能源转化率低等瓶颈。厌氧膜生物反应器(anaerobic membrane bioreactor,AnMBR)是厌氧消化与膜过滤技术有机结合的污水处理新技术。AnMBR在膜截留的作用下,可实现对反应器水力停留时间和污泥龄的解偶联,从而维持反应器内较长的污泥龄及较高的有机负荷,以有效防止产甲烷菌流失,并提升甲烷转化效率。

关键词： Self-forming dynamic membrane   Dynamic cake characterization   Dye reduction   Membrane fouling   Cake layer formation  

摘要： The study aimed at investigating the performance of anaerobic dynamic MBR (AnDMBR) for the treatment of synthetic textile wastewater. A laboratory scale anaerobic bioreactor was operated to test nylon mesh support materials with different pore sizes (20 mu m, 53 mu m and 100 mu m). The performances of the AnDMBR were evaluated with a stimulated wastewater containing 1,000 mg.L-1 COD and 100 mg.L-1 dye (Remazol Brilliant Violet 5R). To develop an effective dynamic cake layer on the support material, different operational strategies, i.e. high flux, continuous and intermittently biogas recycle were studied for process optimization and increase the filtration performances. Initially, the bioreactor was operated under continuous biogas recycle. Under this operation strategy, the cake layer was not formed, then intermittent biogas recycle was applied to improve the development of dynamic layer. Effluent SS decreased below 20 mg-SS.L-1 for all the tested different pore sized supports after the development of the cake layer. Almost complete color (>99%) and high COD removal efficiencies (95-97%) were observed. For all the three supports, the bioreactor was operated at fluxes of 5-15 L.(m(2). h)(-1) (LMH), which was quite high compared to conventional AnMBRs equipped with micro/ultra-filtration membranes. In order to better understand the formation and its structure, detailed cake layer characterization analyses were conducted with scanning electron microscopy (SEM), SEM coupled Energy Dispersive X-ray Spectroscopy (EDS) and inductively coupled plasma-optical emission spectrometer (ICP). Provided the formation of the cake layer, the comparable flux and removal performances with AnMBRs for all three tested support materials were possible.

关键词： 生物反应器   数值模拟   气液两相流   气含率   传质  

摘要： 使用生物可降解塑料是解决白色污染的有效手段,然而在生物反应器中生产可降解塑料过程中会面临气体传质能力不足和能耗过大等问题,导致生产成本居高不下。为解决这些问题,提出了一种共轴反转型机械搅拌式生物反应器,并通过数值模拟对新型反应器内两相流场进行了仿真及定量分析。通过模拟气泡羽流、鼓泡塔及搅拌器系统内流场,并与实验结果对比,在双流体模型中引入了曳力、升力及湍流扩散力以及基于Troshko-Hassan模型的两相湍流模型,验证了双流体模型在该问题中的有效性。对新设计的反应器内流场模拟结果表明,两相作用力模型对模拟准确性影响较大,而共轴反转能够在流场中形成更好的剪切效应,增强气体分散能力,从而提高整体气含率及相对功率准数。

关键词： Electrochemical membrane bioreactor (eMBR)   Electrochemical oxidation   Electrocoagulation   Membrane fouling   Micropollutants   Sludge properties  

摘要： Integration of an electrochemical process with membrane bioreactor (MBR) has attracted considerable attention in the last decade for simultaneous improvement in pollutant removal and hydraulic performance of MBR. Electrochemical MBR (eMBR) with sacrificial anodes has been observed to achieve enhanced phosphorus (up to 40%) and micropollutant removal (5-60%). This is because direct anodic oxidation, indirect oxidation by reactive oxygen species and electrocoagulation can supplement the biological process. The application of an electric field can substantially reduce membrane fouling by 10% to 95% in the eMBR as compared to the conventional MBR. Sacrificial electrodes (e.g., iron or aluminium) have been reported to be more suitable for fouling mitigation than nonsacrificial electrodes (e.g., titanium). However, during prolonged operation, metal ions released from sacrificial electrodes can adversely affect microbial activity and could accumulate in activated sludge. Depending on the current density and electrode material (sacrificial or nonsacrificial), anodic oxidation, electrocoagulation, electrophoresis and/or electroosmosis mechanisms are responsible for suppressing membrane fouling propensity. This paper critically reviews the current status of the electrochemical MBR technology and presents a concise summary of eMBR configurations and electrode materials. Comparative removal of bulk organics, nutrients and micropollutants in the eMBR and conventional MBR is discussed, and performance governing factors are elucidated. Impacts of operating conditions such as current density on mixed liquor properties (e.g., floc size and zeta potential) and microbial activity are elucidated. The extent of membrane fouling mitigation along with associated mechanisms as well as energy consumption is explained and critically analysed. Future research directions are suggested to fast track the scalability of eMBR, which include but are not limited to electrode lifetime, development of