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1.
在硅酸盐水泥熟料中加入铁矾渣,制备成胶凝材料.分别以粉煤灰沸石、硫化钠和粉煤灰为外加剂,研究其对水泥固化体强度和浸出毒性的影响.在胶凝材料中铁矾渣加入量为60%时,加入沸石、硫化钠为稳定剂,均可提高重金属离子的稳定性,不同固化体的浸出毒性值均低于国家标准.在胶凝材料中加入粉煤灰,粉煤灰掺量增加,固化体强度下降,不同固化体的浸出毒性值也均低于国家标准.  相似文献   

2.
为了研究水泥基复合固化剂对重金属混合污染土的固化稳定效果及其与单一重金属污染土的固化效果差别,探究锌和镉离子之间是否有协同或拮抗作用,采用水泥、石灰、粉煤灰和蒙脱石等作为复合固化剂,通过开展无侧限抗压强度试验、毒性浸出试验、X射线衍射分析(XRD)以及电镜扫描分析(SEM),研究锌镉混合污染土在不同固化剂掺量下的强度特性与浸出毒性、pH值与浸出毒性间的关系、重金属混合污染土与单一重金属污染土的固化效果差异,并通过XRD和SEM分别对固化产物的成分和形貌进行微观分析,进而分析固化机理。试验结果表明:用生石灰、粉煤灰、海泡石、蒙脱土替代等量水泥可使固化产物的强度提高;Zn2+与Cd2+之间不存在拮抗作用,Cd2+的存在还会有助于Zn2+的固定;重金属离子的浸出浓度随浸出液pH值的增大而明显降低;固化效果好的样品相较于固化效果差的样品有更多的针状、网状等较为致密的结构。  相似文献   

3.
高重金属含量垃圾焚烧飞灰经高温复合矿渣熔融重构,一次固化制备重构水淬渣,并将重构水淬渣复合水泥体系进行二次固化,采用TCLP法测试并分析垃圾焚烧飞灰双重固化全过程中重金属浸出特征。结果表明:垃圾焚烧飞灰中典型重金属Zn、Cu、Pb和Cr浸出的质量浓度分别高达1 686.00、321.85、10.17和29.96 mg·L-1;重构水淬渣颗粒越细,其重金属浸出质量浓度越高,但均低于固体废物浸出毒性鉴别标准,可安全用于建材行业;重构水淬渣-水泥净浆体系重金属浸出的质量浓度远远低于固体废物浸出毒性鉴别标准,重构水淬渣细度对该体系重金属浸出影响极小。  相似文献   

4.
矿渣硅酸盐水泥水化反应的理论模型与应用   总被引:1,自引:0,他引:1  
提出了一种矿渣硅酸盐水泥水化反应的理论模型,考虑了矿渣成分、熟料成分、矿渣掺量、矿渣水化程度对其水化产物成分和微观结构的影响,可以定量地预测C-S-H凝胶的成分和浆体不同组份的相对比例.与普通硅酸盐水泥浆体相比较,矿渣硅酸盐水泥浆体最主要的差别是Ca(OH)2含量显著降低、C-S-H的钙硅比明显降低,同时孔隙率也不断增加.  相似文献   

5.
为了提高混凝土结构抗硫酸盐侵蚀,采用共沉淀法制备钴铁镁铝四元水滑石,采用固相混合法制备钴铁镁铝水滑石-碳纳米管复合材料。将其应用于水泥净浆中,研究了龄期、浓度对固化硫酸根离子性能的影响,结果表明:和普通水泥净浆相比,加入钴铁镁铝水滑石-碳纳米管后,对SO2-4固化能力得到了明显的提升,在7 d,SO2-4浓度为0.05 mol/L时,其固化量由97.46 mg/g增加到107.11 mg/g;CoFeMgAl-LDHs/CNTs本身对SO2-4固化量随着SO2-4浓度的增加而增加,在SO2-4浓度为0.5~1.5 mol/L时,固化量增长较为平缓,在1.5~2.5 mol/L时,固化量增长较快;固化量随着龄期的增加而增加。  相似文献   

6.
利用固相反应与球磨相结合的方法,制备了(Cu1-xMnx)CrO2 (0≤x≤6 at%) 和 Cu(Cr1-yMny)O2 (0≤y≤6 at%)两个系列的纳米粉体.结果表明,所有样品都具有3R-CuCrO2铜铁矿单相结构.晶格膨胀说明Mn离子已分别固溶到(Cu1-xMnx)CrO2的Cu亚晶格中和Cu(Cr1-yMny)O2的Cr亚晶格中,这在X射线光电子能谱的分析中得到了进一步的证实.B位Mn掺杂样品具有室温铁磁性,磁性源于Cr3+-Mn3+离子对间以空穴为媒介的双交换相互作用.CuMO2(M=Cr,Mn)铜铁矿纳米粉体的饱和磁化强度比文献值高出约一个数量级,并随着Mn含量的增大而逐渐减小,主要受到3个因素的共同影响:M-M离子对数目、M-M离子间距及空穴浓度.  相似文献   

7.
对白魔芋实生种子分别进行4℃层积、室内常温层积和25℃层积处理,应用酶联免疫吸附法(ELISA)测定其内源激素的质量比,并结合发芽试验,探讨种子中内源激素质量比的变化与其休眠萌发的关系.结果表明:①种子经层积处理后发芽率明显高于对照,其中,以25℃层积处理的种子发芽率最高.② 3种层积处理的种子中IAA,GA3,ZT质量比均呈现先升高后降低的趋势,且在层积末期其质量比均高于对照,而ABA与之相反,ABA质量比呈现“V”型变化趋势;所有激素均在层积40~60 d时出现峰值.③ 3种处理的种子中ωIAA/ωABA,ωGA3/ωABA,ωZT/ωABA比值均呈倒“V”型变化趋势,可见,在层积处理40~60 d时,促进萌发的激素质量比较高,而抑制萌发的激素ABA质量比较低.  相似文献   

8.
以固化体强度、增容比、浸出液pH值以及重金属浸出率为指标,通过无侧限抗压强度和毒性浸出试验,考察以碱渣为添加剂辅助水泥固化/稳定化处理生物脱毒底泥的效果。结果表明,脱毒底泥经碱渣预调理后(泥渣比=10∶0.8),在0.2—0.4kg/kg不同水泥掺入量下形成的底泥固化体的无侧限抗压强度均可达140kPa以上(龄期14d),增容比仅为1.17—1.31,固化体浸出液pH值在11.3—11.7之间,Zn、Cu和Cr等重金属浸出得到明显控制(浸出率均≤2.2%).与固化前相比,底泥固化体环境风险大大降低,且满足填土材料与填埋处置要求.从固化效率角度考虑,生物脱毒底泥固化/稳定化实际应用中较为合适的水泥掺入量为0.2kg/kg,即碱渣∶水泥∶底泥=6∶17∶77.  相似文献   

9.
焚烧飞灰水泥固化体的安全性评价   总被引:17,自引:0,他引:17  
通过城市生活垃圾焚烧飞灰水泥固化体中重金属的浸出毒性以及表面浸出毒性等研究 ,对焚烧飞灰水泥固化体的安全性进行了评价 .研究表明 ,水泥稳定固化焚烧飞灰的效果良好 ,焚烧飞灰水泥固化体在实际使用环境中 ,重金属浸出是一个非常缓慢的过程 ,其释放量远远低于国家标准规定值 ,而且 ,环境对微量有害物质还有包容和稀释的作用 ,因此焚烧飞灰水泥固化体不会对环境造成危害 .焚烧飞灰水泥固化体资源化利用是安全可行的 .  相似文献   

10.
分别研究了不同硅酸根与碱金属阳离子比(Si/M比)的钠、钠钾复合硅酸盐溶液和由硅酸盐溶液激发的碱矿渣水泥浆体的黏度和凝结时间。并结合硅酸盐溶液的傅里叶红外光谱试验对溶液中硅酸根离子的聚合度进行研究。结果表明:硅酸盐溶液的Si/M比越低,硅酸根的聚合度越小。在硅酸钠溶液体系中掺入一定量的K+离子可以降低体系中硅酸根离子的聚合度,显著降低溶液和浆体的黏度,使碱矿渣水泥获得更好的工作性能。同时,在较低Si/M比(Si/M≤1.5)情况下,K+离子还能够延长碱矿渣水泥的初凝时间。  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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