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1.
采用聚乙烯醇(PVA)为主要载体,添加少量壳聚糖(SA)、SiO_2和CaCO_3,利用聚乙烯醇-硼酸(PVA-H_3BO_3)包埋法,包埋苯酚降解菌TX1;并制备成胶珠,研究胶珠对含酚废水的降解。通过正交实验、单因素实验和传质性能分析,确定并优化包埋条件。结果表明PVA浓度8%、SA浓度0.2%、SiO_2浓度2.4%、CaCO_3浓度0.4%和饱和H_3BO_3液p H为6.7时,包埋胶珠机械强度好、结构稳定、无泄漏、固定化效果好;同时发现该条件下的固定化细胞培养12 h后对初始浓度为500 mg/L苯酚废水的降解率为78.1%。  相似文献   

2.
酚降解性活性污泥的固定化研究   总被引:3,自引:1,他引:2  
实验确定了以聚乙烯醇(PVA)为包埋剂固定化活性污泥的最佳条件,制备得到了固定化降解苯酚的活性污泥.最佳条件为:PVA质量浓度为100 g/L,交联剂pH值为7.0.固定化后活性污泥性能得到明显改善,缩短或消除了活性污泥降解苯酚的延滞期,可在较短时间内达到高降解率,对于质量浓度为1 500g/L的含酚废水,前5日的降解率可达98.3%.  相似文献   

3.
固定化微生物处理甲醇废水的包埋条件优化选择   总被引:9,自引:0,他引:9  
实验选取高浓度的甲醇废水,利用固定化包埋技术对甲醇废水进行污染物降解处理实验研究.分别以海藻酸钠和聚乙烯醇(PVA)为包埋材料,包埋驯化后的活性污泥,制成固定化小球颗粒,对甲醇废水中COD的降解为指标进行了正交试验.确定出海藻酸钠和聚乙烯醇的最佳包埋条件,并对在最佳包埋条件下制成的固定化小球进行了性能的改进.同时通过对固定化颗粒小球的比表面积、传质性能的测定以及电镜扫描分析了固定化小球的性能.实验表明,交联时间是固定化颗粒活性的主要影响因素;2种材料均有适合微生物附着生长的网状结构;加入添加剂后,PVA固定化小球的机械性能进一步得到改善.  相似文献   

4.
在相同的环境条件下,研究以聚乙烯醇(PVA)与海藻酸钠(SA)以及聚丙烯酰胺(PAM)与海藻酸钠为材料制成的固定化微生物小球对水中石油的降解效果.结果表明;在七天的培养实验中,以PVA为主要材料制成的固定化微生物小球对石油的降解率为80.09%;以PAM为主要材料对石油的降解率为74.40%.以聚乙烯醇与海藻酸钠制成的微生物小球对石油的降解效果要优于聚丙烯酰胺与海藻酸钠.  相似文献   

5.
针对重金属酸性矿山废水酸度和重金属浓度较高的问题,通过静态批实验,采用游离硫酸盐还原菌(SRB)、 SRB厌氧污泥、固定化SRB球状颗粒等修复材料处理模拟酸性矿山废水重金属离子(Zn~(2+)、 Cd~(2+)),探究3种修复材料的处理效果及机理。结果表明,固定化SRB球状颗粒、 SRB厌氧污泥处理重金属酸性矿山废水的效果好于游离SRB的,对硫酸根、重金属的去除效率较高,聚乙烯醇(PVA)、海藻酸钠(SA)包埋法制备的固定化SRB颗粒中的还原铁和生物炭能够提高SRB的活性和SRB对重金属的耐受性,同时包埋法避免SRB与重金属酸性矿山废水的直接接触。  相似文献   

6.
降解低浓度二氧化硫废气的菌株分离及其固定化研究   总被引:5,自引:0,他引:5  
 从硫泉中分离得到17株细菌,用碘量法测定了它们氧化降解SO2的性能.结果表明,菌株R-1氧化降解性能较强,经鉴定,R-1是氧化亚铁硫杆菌(Thiobacillus ferrooxidans).用海藻酸钠(sodiumalginate)进行固定化包埋试验,通过单因素分析,确定了最佳包埋条件.用上柱通气法测定其净化气相SO2的能力,其氧化降解SO2的效率最高达97.01%.结果显示,利用固定化细菌净化低浓度SO2烟气具可行性,但对其稳定性尚待进一步研究.  相似文献   

7.
为构建以铁氰化钾为探针的电化学用于化学品的毒性检测方法,初步探讨了聚乙烯醇(PVA)与添加剂海藻酸钠(SA)、活性炭(AC)共固定包埋大肠杆菌(E.coli)的活性微生物颗粒在实验室废水、毒物3,5-二氯苯酚(DCP)、杀虫剂乙嘧酚以及除草剂五氰磺草胺的水样毒性分析中的应用性能。结果表明:添加剂SA和AC的质量分数均为1%,交联剂CaCl2的质量分数为2%为本研究最优实验条件,此时所测毒物对微生物固定化颗粒的呼吸抑制作用依次为DCP乙嘧酚五氰磺草胺实验室废水,抑制率分别是30.23%~55.35%、25.14%~46.23%、20.12%~38.33%和5.74%~27.89%,抑制率和灵敏度均明显优于仅由PVA-SA单独固定包埋的大肠杆菌颗粒。  相似文献   

8.
选用海藻酸钠(CA)和聚乙烯醇(PVA)混合物作为包埋载体,对经富集培养的以反硝化聚磷菌为主的活性污泥固定化制备方法进行了研究.利用正交实验考察了包埋菌体量、海藻酸钠质量分数、沸石添加量和交联时间对固定化菌除磷效果的影响,着重研究了包埋菌体量和沸石添加量这2个显著性影响因素对固定化小球性能的影响.研究表明,制备固定化反硝化聚磷菌的最佳包埋条件是:PVA质量分数为8%,CA质量分数为3%,包埋菌质量体积浓度为25g/L,沸石质量体积浓度为20 g/L,固定化小球交联时间为18 h.  相似文献   

9.
采用聚乙烯醇(PVA)-海藻酸钠作为包埋材料,以氯化钙和饱和硼酸的混合溶液作为交联剂包埋富集培养后的活性污泥,制成固定化小球。用小球颗粒做乳品废水CODCr的去除试验,通过正交试验研究了3个因素pH、温度、小球颗粒浓度对CODCr去除率的影响程度,并对工艺条件进行了优化。  相似文献   

10.
 阿特拉津因其普遍性、高污染性和难降解性一直是历年来的研究热点.其降解方法很多,其中基于阿特拉津降解菌、生物固定化和一些无机材料的生物降解是最有效的.本文利用磷酸交联剂对聚乙烯醇(PVA)进行改性,以珍珠岩作为添加介质,对阿特拉津降解菌——Pseudomonas W4包埋固定,制备出一种新型珍珠岩-磷酸化聚乙烯醇(PPVA)生物活性材料(简称珍珠岩-PPVA),并对其最佳制备条件以及在不同反应条件下该材料降解阿特拉津的效果进行探讨.该材料最佳制备条件为,珍珠岩(粒径为0.60~2.00mm)/10% PVA(V/V)=35/65,Pseudomonas W4包埋量1.0g/L,磷酸盐浓度1.25mol/L;外加碳源、磷源能够促进其降解阿特拉津;珍珠岩-PPVA在pH值为5.99~9.03时具有较好的降解效果,其抗酸碱能力优于游离W4菌.说明珍珠岩-PPVA可有效去除阿特拉津,可以作为新型材料加以深入研究应用于废水或土壤中阿特拉津降解.  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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