Determination of Antioxidant Capacity by Using Xanthine Oxidase Bioreactor Coupled with Flow‐through H2O2 Amperometric Biosensor

A new flow system for antioxidant capacity (AOC) estimation, consisting of a bioreactor, containing immobilized xanthine oxidase (XOD), coupled with a H₂O₂ amperometric biosensor, based on Os‐wired horseradish peroxidase, was developed. The H₂O₂, resulting from the enzymatic reaction between xanthine (XA) and XOD, was amperometrically monitored at ?0.1 V vs. Ag/AgCl/KCl_sat, in order to avoid the electrochemical interferences. Two protocols were used to perform the AOC evaluation: “steady‐state”, when the antioxidant (AOX) was injected in the XA flow, and “transient state”, when XA and AOX were simultaneously injected in the carrier flow. The AOC of some commercial beverages were evaluated and compared with those obtained with 2,2‐diphenyl‐1‐picrylhydrazyl radical and Folin–Ciocalteu methods.     

混合抗体的亲和色谱分离策略

乳腺生物反应器可以高效表达重组人单克隆抗体,但是目标产品与乳液原料中的牛抗体性质、结构非常类似,分离难度很大。本文对牛抗体和重组人抗体的种属差异进行了分析,并在此基础上制定了新型分离策略,采取Protein A亲和色谱和免疫亲和色谱来解决混合抗体的分离问题,并讨论了色谱洗脱模式对分离效果的影响。结果表明,Protein A亲和色谱结合梯度洗脱可以有效地纯化得到混合抗体,但是难以彻底分离重组人抗体和牛抗体;相比之下,使用Protein A亲和色谱结合置换色谱模式可以更加高效地分离混合抗体,最终可以得到纯度高达95%以上的重组人抗体,回收率可达95%以上。免疫亲和色谱同样可以有效地分离纯化重组单克隆抗体,且其通用性更强,可以应用于任何动物乳腺表达重组人抗体的分离纯化中。     

Impulse and mass transport in a cartilage bioreactor using the lattice Boltzmann method

Mass and Impulse transport of oxygen enriched water in cartilage cell breeding reactor are simulated using the lattice Boltzmann method (LBM). The solver is attached with a shear stress and pressure calculator to quantify the load distribution on the cells. The solver was validated using the backward-facing step flow, which is a classical benchmark of similar discrete geometry for the bioreactor. This is achieved by comparing the qualitative and quantitative results obtained by LBM with the traditional solution and experimental approach for such a problem. The D2Q9 lattice model is used to carry out the calculations for the flow field, with a first order bounce-back boundary condition. Oxygen consumption efficiency levels in the bioreactor were reported.     

MBR中中空纤维膜和板式膜不同的膜污染机理

分析了中空纤维膜和板式膜MBR在膜污染过程中表现出的不同特点,研究了2种膜不同的膜污染机理.平行实验表明,中空纤维膜的膜面附着物是污泥泥饼层,而板式膜的膜面附着物是一层二次动态膜,这导致两者的膜污染杌理有显著区别.泥饼层是中空纤维膜的主要污染因素,二次动态膜则可以缓解作为板式膜主要污染因素的膜孔堵塞污染;同时,由于泥饼层的作用,EPS与中空纤维膜的膜污染相关性良好,而在板式膜中,EPS与其膜污染相关性很差,并且二次动态膜显著降低了SMP与膜污染的相关性;在2种膜长期运行时,相比中空纤维膜过膜压力呈现2个阶段的变化,板式膜的过膜压力经历了3个阶段的变化,这是因为二次动态膜起到了初期缓解膜污染、后期加剧膜污染的作用.     

Application of immobilized psychrotrophs in ICCBR to treat domestic wastewater and its microbiological investigation

To guarantee the efficiency of biotreatment of domestic wastewater in chilly season, six high efficient cold-adapted microorganisms were isolated, and identified as Zoogloea, Aeromonas, Flarobacterium, Micrococcus, Bacillus, Pseudomonas. These cold-adapted microorganisms with 63.67% Chemical Oxygen Demand (COD) removal efficiency higher than that of mesophiles at low temperature were immobilized on soft polyurethane foams and applied to internal circulation compound bioreactor (ICCBR) to treat domestic wastewater. In an experiment period of 12 months, the treatment efficiency, ecological factors, sludge physicochemical properties, and microbiology were studied. Results showed that the average COD removal efficiency in the ICCBR was 85.79% between 4℃ and 10℃ in winter, and 86.66% in the whole year, and COD of systemic effluent was below 60 mg•L⁻¹ which could achieve the first-degree B discharge standard of pollutants in China for municipal wastewater treatment plant. The reduction in microfauna and biomass on carriers could be associated with the seasonal temperature transients, the concentrations of protozoa and metazoan decreased from 110000±30000 microorganisms/mL sludge in summer to 35000±20000 microorganisms/mL sludge in winter, and biomass on carriers increased in the beginning and slightly reduced in the end.     

A/OMBR组合工艺处理酞菁染料KN-G废水

采用厌氧-好氧膜生物反应器组合(A/O MBR)工艺,处理含酞菁染料KN-G废水.研究A/O MBR对酞菁印染废水的降解能力,以及在添加微量元素Mn和不同的进水pH值条件下的降解特性.结果表明:A/O MBR工艺对酞菁染料KN-G印染废水的化学需氧量去除率可达到90%以上,脱色率为63%;添加微量元素Mn,A/O MBR系统对酞菁染料KN-G染料的脱色率下降.当进水pH值为3.0时,平均脱色效率最高达到80%,在酸性条件下酞菁染料的脱色率优于碱性条件.     

混凝-膜生物反应器工艺处理印染废水

采用膜生物反应器对印染废水进行好氧生物活性处理,并对处理水样的化学耗氧量、生物耗氧量、色度和浊度等各项水质指标进行连续测定、分析与处理.实验结果表明:膜生物反应器在混合液悬浮固体(MLSS)质量浓度约5～8 g/L的条件下运行,当系统进水的化学耗氧量(COD_(Cr))为750-900 mg/L,生物耗氧量(BOD)为130-250 mg/L,色度为100-200倍时,出水COD_(Cr),去除率可高达86.6%,BOD、色度、浊度以及悬浮固体(SS)质量浓度几乎为0,处理效果较好.采用混凝-膜生物反应器工艺处理印染废水技术可行.     

脱硫菌最佳载体的选取研究

以炉渣、活性炭和实验室自制生物陶粒作为吸附载体来固定脱硫菌—硫酸盐还原菌（SRB）,并以吸附载体对脱硫菌的吸附量和吸附后的脱硫能力作为衡量标准来筛选固定化载体,最终可确定生物陶粒为脱硫菌的最佳载体。     

好氧颗粒污泥膜生物反应器处理焦化废水

为了提高焦化废水的处理效果,减轻对环境的污染,选择好氧颗粒污泥膜生物反应器处理人工模拟焦化废水,探讨了不同颗粒污泥浓度对焦化废水的处理效果及膜污染的情况。结果表明,不同颗粒污泥浓度对焦化废水的处理效果有显著差别。投加颗粒污泥后,反应器对不同颗粒污泥浓度条件下COD、NH3-N、苯酚、TP的去除效果不同。好氧颗粒污泥内部缺氧和厌氧环境下,反应器中的好氧颗粒污泥质量分数为100%时对COD去除率为99.17%、NH3-N去除率为95.00%、苯酚去除率为99.90%、TP去除率为85.22%。同时,比较了不同颗粒污泥浓度下反应器运行中膜通量的变化趋势及膜表面的变化情况。颗粒污泥投加量的不同对膜污染的抑制作用也不同。颗粒污泥使膜污染减轻,膜通量恢复率升高。     

固定床生物反应器处理铀矿冶废水中NO-3模拟试验研究

针对铀矿冶废水中存在过量硝酸根的问题,通过以轻质黏土陶粒为载体的上流式固定床生物反应器对模拟的铀矿山废水进行了NO－₃的去除试验研究。考察了载体种类、挂膜次数、NO－₃质量浓度、pH、n(C)/n(N)和水力停留时间(hydraulic retention time ,HRT)等因素对反硝化效果的影响,结果表明生物反应器对硝酸根去除效果良好。以NO－₃质量浓度为500 mg/L模拟废水进行流动实验,tHRT由6 h下降至2 h的过程中,反应体系稳定后NO－₃去除率均为100%,达到了预期的去除效果。