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1.
微氧条件下固定化颗粒污泥的氯酚降解及菌群结构   总被引:5,自引:0,他引:5  
将氯酚优势好氧菌与厌氧颗粒污泥以三种不同方式组合:(1)以聚乙烯醇和海藻酸钠为载体,采用冷冻法将氯酚优势好氧菌和厌氧颗粒污泥进行混合固定;(2)将氯酚优势好氧菌单独固定后再与厌氧颗粒污泥混合;(3)将氯酚优势好氧菌直接投加到厌氧颗粒污泥.比较三种固定化颗粒污泥在微好氧及厌氧条件下的五氯酚降解效果.结果表明:在氯酚优势好氧菌和厌氧颗粒污泥的混合固定中,微好氧条件下可通过厌氧菌与好氧菌的协同作用实现氯酚的厌氧好氧同时降解,而在厌氧过程中,三种固定化颗粒污泥的氯酚降解速率没有明显差别.厌氧好氧活性实验也进一步证实了固定化颗粒污泥中厌氧、好氧菌活性的存在,并进一步推导出了微氧条件下氯酚固定化颗粒污泥的菌群结构.  相似文献   

2.
采用DM-130大孔树脂为载体,对脂肪酶进行了固定化,研究了固定化条件对催化活性的影响,得到了最佳固定化条件:温度为45℃,pH值为8.0,吸附时间为6h,载体与脂肪酶的质量比为30:1。  相似文献   

3.
几种交联剂对PVA固定化活性污泥的活性比较   总被引:7,自引:0,他引:7  
为了优化选择聚乙烯醇(PVA)固定化方法中的交联剂,运用氧吸收速率作为评价指标,对聚乙烯醇(PVA)固定化方法中不同交联剂对固定化活性污泥的生物活性的影响进行了研究。采用3种不同交联剂,即饱和硼酸 1?Cl2、50%NaNO3 1?Cl2、饱和硼酸 NaH2PO4,制得PVA固定化污泥。通过测量不同营养液中固定化污泥的氧吸收速率,比较了3种固定化颗粒中自养菌和异养菌的生物活性。试验结果表明:在经过活化之后,各类固定化污泥的生物活性和稳定性均得到很大的提高;而且在3种颗粒中,采用饱和硼酸 NaH2PO4作为交联剂制得的固定化颗粒,其自养菌和异养菌的生物活性最高;该法为利用PVA载体固定化活性污泥的较好方法。  相似文献   

4.
硅 藻 土 固 定 化 脂 肪 酶   总被引:14,自引:4,他引:14  
采用硅藻土作为载体, 对脂肪酶进行固定化, 研究了固定化条件对固定化脂肪酶 的催化活性以及硅藻土吸附脂肪酶量的影响. 得到最适的固定化反应条件: 温度为30~35 ℃; pH值为7.7; 缓冲液离子浓度在0.01~0.03 mol/L之间; 载体与脂肪酶的质量比为 8∶1.  相似文献   

5.
采用上流式厌氧污泥床反应器(UASB)作为反应装置,以颗粒活性炭为污泥载体进行污泥固定化,以豆制品加工废水为发酵底物,考察系统启动过程运行特性及水力停留时间(HRT)对系统运行性能的影响.研究表明,通过调控系统pH值可在20 d达到污泥固定化生物制氢系统的稳定持续产氢运行状态,并通过优化系统HRT条件可实现生物制氢系统的最大产氢量6. 3 L·L~(-1)·d~(-1).  相似文献   

6.
固定化桔青霉发酵核酸酶P1的研究   总被引:3,自引:0,他引:3  
以玉米芯颗粒吸附桔青霉(Penicillium citrirum)孢子,再用1.5%的海藻酸钠包埋吸附固定化细胞玉米芯颗粒,于摇瓶中进行分批培养。实验结果表明:在固定化细胞产酶的条件下,培养基中淀粉水解糖浓度为9g/L,蛋白胨浓度为1g/L,摇瓶转速为180r/min,产酶发酵周期为50h,发酵液中核酸P1的活力高达503U/ml。双载体固定化细胞经30批次连续重复发酵产酶稳定在较高水平,固定化细胞粒子机械强度高。  相似文献   

7.
为考察温度对生物吸附性能的影响,采用传统的静态试验方法,以4-氯酚为吸附质,厌氧颗粒污泥为吸附剂,研究了温度对4-氯酚在厌氧颗粒污泥上吸附性能的影响。实验结果表明:不同温度下4-氯酚在厌氧颗粒污泥上的吸附可以很好地用Langmuir吸附等温方程(L方程)和Freundlich吸附等温方程(F方程)进行描述。L方程和F方程的相关系数R2分别在0.92~0.99和0.82~0.97之间,25℃时达到最高,分别为0.97(L方程)和0.99(F方程)。结果还表明,温度是影响4-氯酚在厌氧颗粒污泥上吸附的重要因素,随着温度的增高,平衡吸附量降低,4-氯酚在厌氧颗粒污泥上的吸附过程为放热过程。  相似文献   

8.
为考察温度对生物吸附性能的影响,采用传统的静态试验方法,以4-氯酚为吸附质,厌氧颗粒污泥为吸附剂,研究了温度对4-氯酚在厌氧颗粒污泥上吸附性能的影响。实验结果表明,不同温度下4-氯酚在厌氧颗粒污泥上的吸附可以很好地用Langmuir吸附等温方程(L方程)和Freundlich吸附等温方程(F方程)进行描述。L方程和F方程的相关系数R2分别在0.92~0.99和0.82~0.97之间,25℃时达到最高,分别为0.97(L方程)和0.99(F方程)。结果还表明,温度是影响4-氯酚在厌氧颗粒污泥上吸附的重要因素,随着温度的增高,平衡吸附量降低,4-氯酚在厌氧颗粒污泥上的吸附过程为放热过程。  相似文献   

9.
膨润土基固定化细胞颗粒材料的研制   总被引:7,自引:0,他引:7  
首次采用成型化的膨润土基多孔粘土材料,作为固定混合脱色菌的载体,成功地制成膨润土基固定化细胞颗粒材料,应用于红色梁液废水的脱色处理,取得良好的效果。探讨载体制备条件对形成微生物细胞颗粒材料的影响,以及润土基固定化细胞颗粒材料染料阳离子红XGRL的脱色作用。  相似文献   

10.
采用载体吸附法的固定化方式培养了高活性的厌氧生物膜颗粒,并研究了反应器的启动运行、工艺特性及污泥特性等规律,探索用生物膜颗粒取代厌氧颗粒污泥的可行性,以缓解国内颗粒污泥供应不足的问题.实验装置采用厌氧附着膜膨胀床,投加人工配水,裸载体为陶粒(湿视密度1310kg·m-3,平均粒径0.32mm).实验分初次启动、二次启动及稳定运行两个阶段进行,反应器仅需24 d就可完成启动,COD容积负荷最高达到18kg·m-3·d-1,相应的COD去除率在70%~80%之间.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

17.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

18.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
1 Rise of studies on climate change's effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America's annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].  相似文献   

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