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1.
光合细菌的分离鉴定及在河蟹养殖中的应用   总被引:2,自引:0,他引:2  
我国水产养殖业迅猛发展,水质恶化日益严重,如何改善水产养殖水域的水质状况已成为水产养殖业发展的关键技术和研究热点.本研究对能净化养殖水质的光合细菌进行研究,分离得到纯菌株S2、S3、S4、S9,鉴定分别为沼泽红假单胞菌,胶质红假单胞菌,荚膜红假单胞菌和球形红假单胞菌.通过一系列试验证明4种光合细菌的混合菌株可有效去除养殖水中CODCr和NH3-N,提高水中溶解氧含量,并促进河蟹生长,为光合细菌在河蟹养殖中的进一步应用提供了理论依据和技术支持.  相似文献   

2.
从保定市护城河及白洋淀底泥中富集分离出6株光合细菌,分别编号为PSB-1、PSB-2A、PSB-2B、PSB-3、PSB-4、PSB-5.通过形态学观察及生理生化特性试验,以伯杰细菌鉴定手册第九版为依据,鉴定认为PSB-1、PSB-2B、PSB-3、PSB-5属于红假单胞菌属(Rhodopseudomonas)的成员,PSB-2A属于红细菌属(Rhodobacter)的成员,PSB-4属于蓝细菌(Cyanobacteria).  相似文献   

3.
6株光合细菌的富集分离及初步鉴定   总被引:4,自引:0,他引:4  
从保定市护城河及白洋淀底泥中富集分离出6株光合细菌,分别编号为PSB-1、PSB-2A、PSB-2B、PSB-3、PSB-4、PSB-5。通过形态学观察及生理生化特性试验,以伯杰细菌鉴定手册第九版为依据,鉴定认为PSB-1、PSB-2B、PSB-3、PSB-5属于红假单胞菌属(Rhodopseudomonas)的成员,PSB-2A属于红细茵属(Rhodobacter)的成员,PSB-4属于蓝细菌(Cyanobacteria)。  相似文献   

4.
报导了沼泽红假单胞菌在暗纹东方育苗中应用的初步研究 .试验过程中按水体 5 0 μg/L的浓度向试验池投放沼泽红假单胞菌 ,研究该菌对育苗池水质、仔鱼育成率以及生长情况的影响 .结果表明 :5 0 μg/L的沼泽红假单胞菌可以有效去除育苗池水的COD(化学需氧量 )、N NH+ 4(氨氮 )以及N NO- 2 (亚硝氮 ) ,从而显著改善育苗池水质 ,稳定水体DO(溶氧 ) ;同时 ,暗纹东方仔鱼育成率以及生长都有了显著的提高  相似文献   

5.
从天津北运河沉积物中分离得到3株以亚硝酸氮(NO-2-N)为氮源的异养硝化菌HN4、HN5和HN6.对3菌株降解NO-2-N与总有机碳(TOC)能力进行了研究.结果表明,3菌株富集培养期内降解NO-2-N与TOC效率均在60%以上,富集培养期间NO-2-N含量变化和TOC含量变化高度相关,3株异养硝化菌能在进行脱氮作用的同时利用有机碳.以细菌16S rDNA序列和真菌ITS序列进行分子生物学鉴定,初步认定HN4为Shigella,HN5和HN6为Candida palmioleophila.  相似文献   

6.
二株细菌处理石油废水的比较研究   总被引:1,自引:0,他引:1  
从成都市郊区加油站附近分离到二株以石油烃类为碳源与能源的优势菌C-1与C-2,初步鉴定为假单胞菌(Pseudomonassp.)与芽孢杆菌(Bacillussp.),采用生物膜法对二株菌降解石油废水能力进行了比较.30℃,1.25L/min通气挂膜2星期后,处理南充炼油厂石油废水,处理效果C-1好于C-2,不同营养盐NH4NO3、K2HPO4·2H2O、NaH2PO4、NH4Cl对菌株C-1处理石油废水的作用不同,浓度为1000mg/LNH4NO3对菌株C-1处理石油废水效果最佳.  相似文献   

7.
目的研究p H值和有机碳源对匹配厌氧氨氧化的前置亚硝化反应的影响,确定实现NO-2-N稳定高效积累的最佳运行参数.方法试验采用人工配水,控制反应温度为28℃,DO质量浓度在1.0 mg/L左右,进水NH+4-N质量浓度为150 mg/L,分别通过静态试验和动态试验考察在不同p H值(6.0、6.5、7.0、7.5、8.0、8.5)和不同COD质量浓度(50 mg/L、100 mg/L、150 mg/L、200 mg/L、250 mg/L)条件下,NH+4-N去除情况和NO-2-N累积情况.结果在本实验条件下,当p H值为7.5~8.0、ρ(COD)150 mg/L时,SBR反应器可以获得理想的亚硝化效果,NH+4-N去除率和NO-2-N累积率分别可以维持在90%和75%以上.结论 p H值偏碱性有利于实现较高质量浓度的NO-2-N积累.当进水中存在适量有机碳源时,匹配厌氧氨氧化的亚硝化反应可以正常进行,但有机碳源质量浓度过高会对亚硝化细菌的生长繁殖产生明显的抑制作用.  相似文献   

8.
光合细菌是的水体微生物,在水体中有重要的生态作用.为了用于本地区的水体净化,从南湾水库分离了一株光合细菌菌株(PSB-1),初步菌体液体培养物为红色.研究了它的生理生化特征和菌落特征,拍摄了电子显微照片.结果鉴定为红螺菌科沼泽红假单胞菌(Rhodopseudanonas palustris).  相似文献   

9.
从养殖池塘底泥样品中分离纯化得到紫色非硫光合细菌1株,通过观察分离菌株的细胞形态结构和16SrDNA序列分析,鉴定该株光合细菌属于沼泽红假单胞菌(Rhodops eudomonaspalusteris).采用三级扩大培养法生产光合细菌,活菌数达3×10~9 cfu/mL.在草鱼鱼苗养殖池塘投加光合细菌,可维持池塘透明度,明显降低亚硝酸盐和氨氮含量.  相似文献   

10.
从荚膜红假单胞菌细胞中提取类胡萝卜素,探讨光照、pH、金属离子、温度和氧化还原剂等对色素稳定性的影响.结果表明,光、温度、酸碱、Fe+3、Cu+2、H2O2和Na2SO3对荚膜红假单胞菌类胡萝卜素的稳定性均有较大影响,而金属离子Na+、Ca+2、K+、Zn+2与抗坏血酸对色素稳定性无影响.荚膜红假单胞菌类胡萝卜素在中性pH下、避光4℃冷藏,其稳定性较好.  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.
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   

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.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
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   

18.
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   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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