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1.
用藻类生长抑制试验研究光电催化水中五氯酚毒性特征   总被引:1,自引:0,他引:1  
采用96h藻类生长抑制试验考查了光电催化水中五氯酚过程中以及不同降解条件下的急性毒性变化规律.结果表明,光电催化去除五氯酚水溶液毒性的能力高于直接光解、电氧化;光电催化降解五氯酚的过程中溶液毒性逐步降低,反应2h后,溶液的毒性降低到初始毒性的11%.反应最佳条件为电解质Na2SO4浓度0.01mol/L,pH在7左右.  相似文献   

2.
催化湿式氧化法处理含酚废水   总被引:13,自引:1,他引:13  
进行了CuO/A12O3、CuO-MnO2/Al2O3、CuO-K2O/Al2O3、CuO/CeO2催化剂在160℃和1.6MPa的氧气压力条件下,催化氧化法处理含酚废水的实验,结果表明催化剂CuO/CeO2具有最高的催化活性,COD为3000ms/L左右含酚废水,反应50min后降解97%。并测定了在135~165℃和1.6MPa氧气压力下。加入催化剂CuO/Al2O3氧化含酚废水的COD与时间的的关系,求取了反应的动力学方程。初步探讨了氧分压和溶液的pH对催化氧化反应速率的影响。  相似文献   

3.
高压脉冲放电低温等离子体法降解废水中4-氯酚   总被引:17,自引:0,他引:17  
考察了多种因素对高压脉冲放电低温等离子体法降解废水中4-氯酚的影响。对降解过程所得的中间产物和终产物进行了分析。结果表明,提高脉冲电压峰值、延长放电时间、无机盐FeSO4的存在均可提高降解效果,自由基清除剂及缓冲剂的存在会显著降低降解效果。对100mg/L4-氯酚废水放电处理240min,是高降解率可达90%以上,降解产物主要有苯酚、对苯二酚、邻苯二酚、对氯邻苯二酚和对苯醌等。当放电时间足够长时,4-氯酚可完全降解为CO2和H2O等无机小分子。  相似文献   

4.
优势光合细菌处理炼焦废水的研究   总被引:4,自引:0,他引:4  
研究了从炼焦废水生物处理系统中分离出的PSB菌对炼焦有机废水的静态处理及动态处理试验,同时对PSB降解有机污染物的机理进行了探讨.结果表明,在pH为7及有氧条件下,PSB对炼焦有机废水有较好的处理效果,其有机物去除效率基本都在90%以上,脱酚效率达96%以上,氰化物去除率高达92%,氨氮去除效果在68%以上.  相似文献   

5.
对P-25 TiO2光催化剂在空气气氛中进行程序升温热处理,用于对高浓度苯酚废水的光催化降解.考察了焙烧温度、催化剂用量、溶液pH和H2O2对光催化降解苯酚的影响,并采用XRD和BET方法对各种温度焙烧的P-25 TiO2进行了表征.结果表明,500℃焙烧的P-25 TiO2光催化降解苯酚效率最高,适宜的晶相结构是500℃焙烧的P-25 TiO2光催化剂表现出较高催化活性的原因.苯酚在催化剂用量为2.0g/L、pH为7.0左右时降解较为适宜.HiO2对苯酚的光催化降解影响显著,在溶液中加入少量H2O3可大幅度提高光催化降解苯酚效率.  相似文献   

6.
电化学降解含酚焦化废水的研究   总被引:1,自引:0,他引:1  
选用Ti/Ir2O3/RuO2为阳极,C-PTFE气体扩散电极为阴极降解模拟含酚焦化废水。利用正交实验,求出最佳操作条件。考察了苯酚浓度、电流密度、电解质浓度、pH值等因素对苯酚去除效率的影响。对电化学降解苯酚进行动力学分析,蛄果证明了其反应为一级动力学反应。  相似文献   

7.
均相和非均相Fenton型催化剂催化氧化含酚废水   总被引:31,自引:4,他引:31  
研究了均相和非均相Penton型催化剂催化氧化含酚废水.对均相催化氧化反应进行正交试验和单因数试验,确定其氧化降解特定废水的最优化条件.在Fenton反应机理的基础上,探讨了Fe^3 在均相和非均相条件下的催化氧化机理;制备了Fe^3 /人造沸石和Fe^3 /活性炭催化剂;进行了非均相催化氧化降解高浓度含酚废水的试验;比较了均相和非均相催化氧化反应对苯酚降解率的影响.结果发现非均相反应能大大提高苯酚降解率,使用Fe^3 /活性炭为催化剂时可使苯酚的降解率达到93.02%.  相似文献   

8.
Ti/SnO2-Sb2O5电极催化电解含硝基苯酚废水的研究   总被引:8,自引:0,他引:8  
用Ti/SnO2,Sb2O5电极研究了含2-,3-,4-硝基苯酚、2,4-二硝基苯酚及2,4,6-三硝基苯酚模拟废水的电催化降解.研究了初始浓度、Cl离子对降解效率的影响并初步分析了电解中间产物.结果表明用Ti/SnO2-Sb2O5电极催化电解处理含硝基苯酚的有机废水是一种有效的方法.  相似文献   

9.
采用Fenton试剂预处理高氯化工废水,考察了主要影响因素,确定了最佳工艺参数.结果表明,在pH值为4,H202投加量325mmol,FeSO4投加量20.8mmol,反应时间90min的条件下处理250mL废水。COD去除率达到64%以上,B/C值由0.016提高到0.35,水质得到明显改善,有利于后续生化处理.  相似文献   

10.
探索了嗜热菌BF80分别在南充炼油厂废水、西河废水、印染厂废水中的生长和苯酚降解情况.结果表明:BF80在炼油厂废水中可正常生长并降酚,在添加0.5%酵母粉后的西河废水中能够旺盛生长并大量降酚,在印染厂废水中完全不能生长.为该菌株处理含酚废水提供了一定的依据.  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.
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   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
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   

15.
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   

16.
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   

17.
18.
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   

19.
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   

20.
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   

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