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1.
硅酸二钙(Ca2SiO4简写为C2S)是硅酸盐水泥的主要成份,对硅酸二钙进行掺杂改性。可以影响C2S的微观结构,水化活性,烧成速度等.用正电子湮没技术研究了掺Na2O和P2O5的C2S正电子寿命谱,结果表明掺杂能增加C2S的微结构缺陷,使C2S烧成速度加快,水化活性增大.用正电子湮没技术X射线衍射线宽效应和扫描电镜等手段研究了不同燃烧条件下,C2S的中间体CaO的活性及其变化规律.结果表明,在快速烧成条件下的新生态CaO晶粒尺寸小,缺陷浓度高,CaO与C2S的活性也较高在硅酸盐水泥生料中掺杂和采用快速烧成工艺,可以增大硅酸盐水泥的烧成反应速度,有重要的实用价值.  相似文献   

2.
本文讨论了碱和液相碱度对少熟料低碱度钢渣水泥强度的促进作用。结果表明:水化液相具有高碱度和富Na2SO4的水化环境将促进低碱度钢渣和矿渣的水化,高C3S适量F—CaO的立窑熟料能显著改善少熟料低碱度钢渣水泥体系的早强和后期强度性能。  相似文献   

3.
研究了磷对C4A3S单矿物及C3S-C2S-C4A3S-C4AF-CaSO4五元系统矿物形成及其水泥性能的影响。结果表明,少量的磷能改善系统的易烧性,降低烧成温度。当P2O5含量小于0.3%时,基本不影响C3S的形成,但降低水泥3d强度,而7d,28d强度增进幅度较大;磷阻碍C4A3S单矿物的形成,当P2O5达0.5%以上时,系统的C4A3S及C3S形成量明显减少,f-CaO升高,水泥各龄期强度均显著降低。  相似文献   

4.
用一系列含同摩尔Na^+浓度的NaCl、Na2CO3、Na2SO4溶液以及用磷酸中和至PH值与含同摩尔Na^+浓度的NaCl溶液的PH值相等的Na2CO3溶液处理生长期为30天的玉米幼苗。处理一周后,测定离子含量、渗透势、光合性能和叶绿素含量等各项生理指标。结果表明:在同摩尔Na^+浓度条件下,玉米幼苗在NaCl、NaCO3和Na2SO4胁迫下产生胁变的顺序为:Na2CO3〉NaCl〉Na2SO4  相似文献   

5.
在50、100和200mmol/l下,研究了NaCI、Na2SO4和Na2CO3对小麦高生长、生物量生长、脯氨酸及Na+,K+含量的影响。NaCI处理使高度下降8.8%~35.4%、而Na2SO4和Na2CO3分别为8.8%~77.9%和53.1%~100.0%。NaCI处理使鲜重和干重分别降低14.3%~42.9%和6.1%~36.7%,而Na2SO4处理分别为14.3%~64.3%和7.2%~58.9%,Na2CO3处理分别为50.0%~74.1%和48.3%~72.8%。在NaCI、Na2SO4和Na2CO3处理下,脯氨酸含量分别增加0.0%~66.7%、0.0%~33.3%和66.7%~100.0%。Na+/K+分别提高2.5~11.9、3.6~114.1和35.1~156.6倍。结果表明:Na2CO3的胁迫比Na2SO4强,而Na2SO4的胁迫影响又比NaCl强  相似文献   

6.
测定了NaCl、KCl、Na2SO4、K2SO4、Na2CO3、Na3PO4在PEG水溶液中的相对粘度,利用Jones-Dole方程求出了粘度B系数,结果表明B系数具有良好的加和性,以KCl为参考电解质计算了单个离子B系数,发现SO^2-4,CO^2-3,PO^3-4的B系数随着PFG浓度的增大而减小,温度系数dB/dT大于零,表明SO^2-4,CO^2-3,PO^3-4对PEG水溶液结构呈破坏作  相似文献   

7.
定量研究了2;4-二硝基苯胺以NaHS,Na2S2或Na2/NaHCO3为还原剂的 选译还原;处在邻位的硝基优先被还原,其选择性约90%。反应介质是影响选择性 的主要因素;还原能力的顺序是NaNS>Na2S2>Na2S/NaHCO3。 这几种还原剂 均适用于本反应。其中以Na2S2为最好。  相似文献   

8.
十二烷基磺酸钠微乳状液的相行为及其结构转变   总被引:2,自引:0,他引:2  
制备了C12H25SO3Na/nC4H9OH/nC7H16/H2O和Na2SO4/H2O/C12H25SO3Na/nC4H9OH/nC7H16体系在km=WC4H9OH/WC12H25SO3Na=2时的相图.测定了起始含油质量分数为21的上述表面活性剂辅助表面活性剂正庚烷体系在纯水和在不同浓度Na2SO4水溶液中单相微乳状液的电导率随含水量的变化曲线.由电导率曲线研究了微乳状液由W/O→二连续→O/W型的结构转变.  相似文献   

9.
NaCI,Na2SO4和Na2CO3对小麦生长,脯氨酸及NA^+,k^+含…   总被引:1,自引:0,他引:1  
在50、100和200mmol/1下,研究了NaCI、NaSO4和Na2CO3对小麦高生长,生物量生长,脯氨酸及Na^+,k^+含量的影响。NaCI 处理使高度下降8.8%-35.4%、而Na2SO4和Na2CO3分别为8.8%-77.9%和53.1%-100.0%。结果表明:Na2CO3r elw rpd xx Ndisplay status  相似文献   

10.
研究了在CH3OH,C2H5OH,H2O3种溶剂体系中^99mTcO4-,乙酰苯肼、还原剂与本体Et2NCS2Na的反应,以制备含  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.
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   

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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