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关键词： 8-HETE   UPLC-MS/MS法   人血浆替代基质   不确定度   扩展不确定度  

摘要： 目的评定UPLC-MS/MS法测定人血浆替代基质中8-HETE浓度的不确定度。方法借助数学模型分析不确定度的来源,确定影响因素。以A类评定程序评价分析过程中随机效应引起的不确定度,以B类评定程序评价分析过程的其他因素引起的不确定度,包括:称量、标准品纯度、量瓶允差、移液器及移液管允差、回收率及标准曲线的拟合等,计算合成不确定度及扩展不确定度。结果置信概率P为95%时,人血浆替代基质中低(2.06μg/L)、中(25.28μg/L)、高(80.72μg/L)浓度8-HETE的扩展不确定度分别为1.44μg/L、3.08μg/L及8.78μg/L。结论本方法绿色环保,样品回收率高,数据准确、可靠,适用于UPLC-MS/MS法测定人血浆替代基质中8-HETE浓度,测量不确定度主要由线性回归过程引入,其他分量影响较小。该方法能够满足检测标准的要求,确保数据的国际互认。

关键词： 计算流体力学(CFD)   膜生物反应器(MBR)   曝气   多孔介质  

摘要： 利用Fluent软件对曝气膜生物反应器中气液两相流动进行模拟计算,探讨了进气气泡的直径、进气速度及膜纤维束的长度等因素对膜生物反应器内液体流动、气体分布的影响。结果表明,减小气泡的直径并适当增大进气速度、膜纤维束长度可以有效提高膜生物反应器内气体的分布和液体与气体的接触,从而促进气液两相进行高效的传质。

关键词： 氨氮(NH_(4)^(+)-N)   游离氨(FA)   游离亚硝酸(FNA)   短程硝化   中试膜生物反应器(MBR)  

摘要： 为探究FA(游离氨)与FNA(游离亚硝酸)对短程硝化及微生物群落结构的影响,采用中试MBR(膜生物反应器),以高浓度NH_(4)^(+)-N废水为处理对象,考察MBR对NH_(4)^(+)-N的去除效果,通过计算FA与FNA浓度,分析其对短程硝化的影响,利用16S rRNA基因高通量测序技术分析微生物群落结构并对功能基因进行预测.结果表明:①通过将NH_(4)^(+)-N容积负荷逐渐从0.11 kg/(m^(3)·d)提升至0.75 kg/(m^(3)·d),MBR在第18天实现了全程硝化向短程硝化的转变.②MBR稳定运行过程中,FA和FNA浓度分别维持在1.03~3.52和0.033~0.118 mg/L,NAR(亚硝酸盐积累率)为65.70%~80.24%,实现了NO_(2)^(-)-N的稳定积累,此时NH_(4)^(+)-N去除率为87.92%~97.18%.③进水由模拟废水向实际工业废水的转变没有对NAR产生较大影响,表明中试MBR具有较强的适应能力.④16S rRNA基因高通量测序分析结果表明,维持MBR内FA和FNA浓度能够富集AOB(氨氧化菌)Nitrosomonas(7.99%),抑制NOB(亚硝酸盐氧化菌)活性,进而实现短程硝化;MBR运行第50天时,Amo(氨单加氧酶)功能基因相对丰度为第0天时的371倍,进一步验证了短程硝化过程的实现.研究显示,FA与FNA对NOB的抑制在维持中试MBR短程硝化中起重要作用,微生物群落结构的变化与MBR内FA和FNA浓度有关.

关键词： Polyhydroxyalkanoates   High cell density culture   Astaxanthin  

摘要： A cell retention culture of Paracoccus sp. LL1 was performed in a membrane bioreactor equipped with an internal ceramic filter module to reach high cell density and thus enhance the co-production of polyhydroxyalkanoates (PHA) and astaxanthin as growth-associated products. Cell retention culture results showed that PHA accumulation increased with increasing dry cell weight (DCW), giving rise to a maximum of 113 +/- 0.92 g/L of DCW with 43.9 +/- 0.91 g/L of PHA (38.8% of DCW) at 48 h. A significant increase in both intracellular and extracellular astaxanthin concentrations was also recorded during fermentation process achieving a maximum of 8.51 +/- 0.20 and 10.2 +/- 0.24 mg/L, respectively. Amounts of PHA and total astaxanthin produced by cell retention culture were 6.29 and 19.7-folds higher, respectively, than those recorded under batch cultivation. PHA and total astaxanthin productivities by cell retention culture also increased up to 0.914 g/L/h and 0.781 mg/L/h, respectively, which were 3.54 and 11.1-folds higher than those of batch culture. Based on gas chromatography, Fourier transform infrared spectroscopy, and 1H nuclear magnetic resonance spectroscopy, the extracted PHA was identified as a copolymer of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) with a 3-hydroxyvalerate content of 3.78 mol%.

关键词： 昆明理工大学   高等真菌   发酵工程   代谢工程   生物反应器   可持续开发利用   活性功能   活性物质  

摘要： 研究室现有研究人员3人,其中教授1人,副教授2人。近年来已培养微生物学和生物工程专业研究生30余名,在读硕士9人、博士1人。团队长期从事高等真菌发酵工程与代谢工程研究,构建活性功能物质高效生产工程菌株,建立菌丝体悬浮培养方法,在生物反应器上实现活性物质的大量生产,为高等真菌资源可持续开发利用、产业创新发展提供重要的理论与技术保障。

关键词： Membrane bioreactor   Fouling   Permeate backwashing   NaClO backwashing   UV irradiation  

摘要： Membrane fouling is a major bottleneck to cost effective application of membrane bioreactor (MBR) for wastewater treatment. This study evaluated a novel fouling control strategy of using UV irradiation to enhance the effectiveness of backwashing. Coupling UV irradiation with NaClO backwashing resulted in significantly lower membrane fouling, suggesting a higher fouling control efficacy than only NaClO backwashing. The signal molecule (C8-HSL) monitoring results suggested the NaClO backwashing could remove the foulants but lead to bacterial stress and thus resulted in more signal molecule being secreted by the microorganisms in the MBR. In contrast, UV irradiation in the mixed liquor constantly suppressed the signal molecule levels and thereby inhibited the fouling development. The confocal laser scanning microscopy analysis suggested that the significant formation of large bacterial aggregates on the membrane surface were avoided after UV assisted backwashing compared to permeate or NaClO backwashing without UV irradiation. Besides, the UV assisted backwashing did not significantly affect the microbial community structure and compromise the water treatment performance of the MBR.

关键词： Membrane bioreactors   External membrane   Submerged membrane   Reversible and irreversible fouling rates   Box-behnken experimental design  

摘要： The response surface methodology has been applied to study reversible and irreversible fouling rates caused by anaerobic sludge in membrane bioreactors, with the aim of controlling membrane fouling by adjusting filtration conditions. The challenge of obtaining statistically significant results of long-term fouling by means of mid-term assays has been addressed. The individual and combined effects of the filtration flux, backwashing intensity, gas sparging and crossflow velocity on membrane fouling, were analyzed in two types of membranes: an external tubular membrane and a submerged hollow fiber membrane. In the external membrane, the reversible fouling rate was as low as 0.27 +/- 0.10 mbar/min, depending mainly on the filtration flux and gas sparging. However, the principal control parameter of the irreversible fouling rate was the crossflow velocity, reaching 2.12 +/- 1.75 1012 m 2 in terms of increase of resistance per cubic meter filtered by square meter of membrane. In the submerged membrane, the irreversible fouling rate was quite lower, 0.78 +/- 0.40 mbar/d, despite the reversible fouling rate was higher, 1.26 +/- 0.42 mbar/min. In this case, the irreversible fouling depended mainly on the backwashing frequency despite the reversible fouling was more affected by the filtration flux and gas sparging. Hence, the approach used to control the reversible fouling rate does not involve mitigating irreversible fouling on both submerged and external membranes. This study provides a methodological basis for the selection of site-specific operating conditions, under which sustainable operation of membrane bioreactors could be achieved.

关键词： 固态发酵   生物反应器   菌剂  

摘要： 固态发酵在食品发酵、饲料加工、生物制药、环保菌剂等生产中的应用越来越广泛。固态发酵生物反应器的开发也随之成为研究的热点。固态发酵中如何根据物料差异、传质需求、开放环境以及规模放大等特征参数,设计反应器并实现自动化和智能控制发酵过程是亟待解决的关键共性技术问题。对固态发酵生物反应器的类型、特征等相关的研究和应用进展进行评述,并建议根据我国国情,利用固态发酵生物反应器进行有机污染物降解菌的扩繁。

关键词： 餐厨沼液   膜生物反应器(MBR)   膜通量   气浮   预处理  

摘要： 随着我国垃圾分类制度的实施和推广,餐厨垃圾已逐步实现单独收集、运输和处置。湿式厌氧工艺是目前餐厨垃圾处理的主要工艺,伴有大量餐厨沼液产生。实际工程多采用膜生物反应器(MBR)处理餐厨沼液,但膜生物反应器(MBR)系统超滤膜通量受沼液进水水质影响较大。本论文通过工程试验探讨了气浮系统对餐厨沼液的预处理效果,试验结果显示:气浮预处理对沼液中的SS、COD、油脂、TP均有较显著的去除效果,能优化膜生物反应器(MBR)的进水水质,利于保持超滤膜系统通量的稳定性。

关键词： 碳中和   微藻   资源化   废水处理   光生物反应器  

摘要： 污水资源化高效回收利用是实现碳中和的关键一环。基于微藻的污水处理技术可实现同步污染物去除,从而达到环境保护和高附加值产品资源转化的碳中和目标。从微藻培养工艺中藻种种类、光生物反应器的特性以及基于光、二氧化碳、菌藻共生体系的微藻强化技术,营养物质、环境因子等对微藻培养的影响因素,微藻处理废水机制以及未来研究方向展望等方面进行详尽阐述,以期为微藻资源化技术处理废水的应用提供理论与技术支持。