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1.
利用动态水热合成工艺,用电石渣作钙质原料合成了硬硅钙石活性料浆。采用XRD和SEM对合成的硬硅钙石料浆结构和形貌进行了检测及表征。结果表明,煅烧后的电石渣可以制备出纯度较高的,毛栗状球形"二次粒子"明显,且数量多直径大的硬硅钙石活性料浆。研究表明,制备硬硅钙石为电石渣二次回收利用提供了一条有效的途径。  相似文献   

2.
研究了CaCl_2、Sr(NO_3)_2、Mn(CH_3COO)_2·4H_2O和ZrOCl_2·8H_2O作为矿化剂对硬硅钙石纤维合成过程、形貌和性能的影响规律;同时,采用场发射扫描电镜、X射线衍射等测试手段对硬硅钙石纤维显微形貌和物相进行分析和表征。结果表明:配料中加入CaCl_2、Sr(NO_3)_2,硬硅钙石的球形团聚体未明显变大,粒子呈片状结构,体积密度较大。加入矿化剂Mn(CH_3COO)_2·4H_2O、ZrOCl_2·8H_2O,硬硅钙石纤维细长且交织缠绕,形成了良好的中空结构,故合成产物体积密度较小,这有利于提高硬硅钙石的保温隔热性能。  相似文献   

3.
晶质二氧化硅与工业石灰水热合成硬硅钙石反应历程   总被引:1,自引:0,他引:1  
针对硬硅钙行水热反应历程研究中存在的分歧,以不同活性的石英粉和工业石灰为原料,在200℃保温条件下对此进行了研究.X射线衍射及SEM扫描电镜对水热产物的分析结果表明,原料活性,尤其晶质二氧化硅的粒度,对硬硅钙石水热反应历程有很大影响.石英粉的中位径为13.13μm时,SiO2与Ca(OH)2的水热反应经过C-S-H相后,不经过托贝莫来石中间相,直接转化为硬硅钙石相.而石英活性较大时,托贝莫来石与硬硅钙石共存于水热产物中.通过控制原料活性以及反应条件,可提高硬硅钙石转化率,有利于提高硬硅钙石型保温制品的性能.  相似文献   

4.
为了研究纤维加入量和烧制温度对硬硅钙石性能的影响,采用动态水热法合成硬硅钙石。在硬硅钙石粉体中加入硅酸铝陶瓷短纤维,压滤成型后烘干,并在600、800和1 000℃分别煅烧2 h。结果表明:硬硅钙石试样的抗弯强度随温度增加而增大,1 000℃烧制的试样中硬硅钙石纤维熔融形成珊瑚状骨架结构,具有较高的抗弯强度。当烧制温度为1 000℃时,纤维质量分数为10%和15%时的样品抗弯强度较好;当纤维质量分数为15%时,导热系数为最低值0.139 8 W/(m·K);陶瓷纤维掺量的增加使硬硅钙石试样的体积密度增大。  相似文献   

5.
根据硬硅钙石-气凝胶复合绝热材料的微观结构特点,建立了描述材料内气固耦合导热的三维单元体传热模型.通过模型计算对硬硅钙石型硅酸钙、气凝胶及硬硅钙石-气凝胶复合绝热材料的导热系数进行了对比研究.结果表明:硬硅钙石型硅酸钙密度是影响复合绝热材料有效导热系数的关键因素,而气凝胶密度的影响不大;在高温下,复合绝热材料的导热系数要明显低于硬硅钙石型硅酸钙及二氧化硅气凝胶的导热系数.  相似文献   

6.
采用金红石型钛白粉和超轻硬硅钙石型硅酸钙为隔热功能填料,制备复合隔热外墙乳胶涂料。研究了钛白粉掺量和硬硅钙石掺量对涂层隔热性能的影响,以及钛白粉和硬硅钙石协同作用对隔热性能的影响。研究表明:分别添加钛白粉和硬硅钙石均能提高涂层的隔热性能;复合添加钛白粉和硬硅钙石能进一步提升涂层隔热性能,复合涂层的热反射率可达80.54%,超过M IL-E-46117标准中热反射率高于75%的要求。  相似文献   

7.
通过观察水泥净浆试件在电脉冲和常规浸泡条件下不同龄期的外观变化,并结合扫描电镜(SEM/EDS)、X射线衍射、红外光谱(FTIR)分析侵蚀产物的组成,对试件遭受硫酸盐侵蚀后碳硫硅钙石的生成速度进行了比较.结果表明:电脉冲明显加速了水泥基材料中碳硫硅钙石的生成速度.在电脉冲作用90~120天时试件内部有一个生成碳硫硅钙石的准备期,作用120天后侵蚀产物中出现大量的碳硫硅钙石;常规浸泡1年后,试件内部只检测到生成碳硫硅钙石所需的中间体,并无大量碳硫硅钙石生成.  相似文献   

8.
C2S对硬硅钙石型硅酸钙保温材料质量影响   总被引:2,自引:0,他引:2  
研究了以天然石灰和天然粉石英为基本原料,添加了2CaO,SiO2对合成硬硅钙石型硅酸钙保温材料的影响,结果表明,随着2CaO,SiO2加入量的逐渐增多,硬硅钙石型硅酸钙保温材料的烘干收缩率逐渐降低,当添加量由0上升到5%时,制品的烘干收缩率由2.19%降低到0.92%,制品由不合格变为合格;烘干收缩率降低的原因是2CaO.SiO2的加入促进了二次粒子形成。  相似文献   

9.
制备条件对硅酸钙复合纳米孔超级绝热材料热导率的影响   总被引:1,自引:0,他引:1  
为解决SiO2气凝胶质脆和硬硅钙石热导率偏高的问题,以正硅酸乙酯为硅源采用溶胶-凝胶法制备SiO2气凝胶先驱体,而后将其与硬硅钙石复合经超临界干燥制备了硅酸钙复合纳米孔超级绝热材料.采用瞬时热带法测试样品常温下1.01×105~1×10-2Pa范围内的热导率,研究了制备条件对复合材料热导率的影响.结果表明,复合材料热导率随硬硅钙石体积质量的减小以及复合增重率的增加而降低,但随气凝胶体积质量的增大先降低后升高.  相似文献   

10.
以电石渣和白炭黑为原料合成硅钙石,并以硅钙石为晶种结晶,考察了不同钙硅摩尔比对硅钙石及磷结晶产品结构的影响;研究发现钙硅比的差异对硅钙石及磷结晶产品的影响较大,钙硅比为1.75∶1时合成羟基硅钙石与磷酸盐反应后的磷结晶产品主要为晶型异常的羟基磷灰石晶体,而其他几种钙硅比下的磷结晶产品主要为不同形式的磷酸钙,不同的钙硅比导致了硅钙石结晶程度的差异,影响了其反应活性,进而影响硅钙石释放Ca2+和OH-的能力,因此得到不同结构的磷酸钙及羟基磷灰石;钙硅比为1.75∶1的条件下合成的羟基硅钙石最有利于以结晶为羟基磷灰石的形式从废水中回收磷。  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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