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1.
通过 XRD、DTA对合成的 CMS、CFS、C3MS2 的水热活性及水热产物进行了研究。结果表明 :常温下不具有水硬性的 CMS、CFS、C3MS2 在水热条件下具有水硬性 ;水热活性 :C3MS2>CMS>CFS;CMS、C3MS2 水热形成富镁的水化硅酸钙 ,CFS水热形成富铁的水化硅酸钙  相似文献   

2.
以硝酸镧为原料,以炭黑作吸附剂,利用正交实验法设计出实验方案,用碳吸附水热合成法制备出氧化镧纳米粉体。研究了溶液酸碱度(p H)、水热时间、煅烧温度对纳米氧化镧生成的影响。结果表明,氢氧化镧在750℃下煅烧2 h,可以有效转化为纳米氧化镧粉体;溶液p H增大,平均原始粒径下降,团聚现象加剧,反应前加入炭黑可有效降低纳米氧化镧粉体的团聚程度。  相似文献   

3.
通过研究富镁低碱度钢渣的水热反应得出富镁低碱度钢渣具有水热活性,水热条件下形成具有胶凝性的富镁水化硅酸钙产物.钢渣中CMS、C3MS2的水热活性高于纯CMS、C3MS2的水热活性.Mg2+优先固溶于水化硅酸钙中,其余部分根据水热温度不同而形成Mg(OH)2或蛇纹石.  相似文献   

4.
以NH4VO3、LaCl3·nH2O等为原料,采用水热法合成了铕掺杂LaVO4纳米粉体,通过X射线粉末衍射、扫描电子显微镜、荧光测试仪等对制备的粉体进行了表征,考察了不同水热体系pH值(4-13)对产物晶相、微观形貌及荧光性能的影响,探讨了LaVO4晶体的生长机理.结果表明:产物的微观形貌为纳米颗粒或纳米棒,pH值低于10时,产物为单斜相LaVO4纳米晶,荧光强度较低;当pH值为11-13时,产物为四方相和单斜相两相,表现出较强的荧光性.  相似文献   

5.
采用优质生石灰、低铁粘土和石膏为原料 ,通过水热合成、低温煅烧工艺 ,初步探索了低温合成白水泥的可行性 ,并用 XRD和 DTA分析了水热合成的产物及低温煅烧形成的矿物 .分析认为水热反应形成的产物是 C3AH6和 C2 SH(A) ,低温煅烧后形成的矿物是结晶程度极差的 C12 A7和 β-C2 S及部分 f Ca O(游离 Ca O) .通过测定净浆水泥的力学性能 ,分析了水泥的水化产物 ,从理论上探讨了水泥的形成及水化机理 .  相似文献   

6.
原硅酸钙在铝酸钠溶液中的反应行为   总被引:2,自引:0,他引:2  
以CaO和SiO2为原料合成2CaO·SiO2,通过测定SiO2浓度分析原硅酸钙反应活性的变化规律;基于质量守恒,计算渣中钠硅渣和钙硅渣分配比例.实验结果表明,在铝酸钠溶液体系中,反应时间的延长、氧化铝浓度的升高均有利于原硅酸钙的分解和溶出液中二氧化硅浓度的升高,溶出液中二氧化硅浓度最高增幅可分别达到9.97倍和11倍;同时,温度升高会显著促进原硅酸钙的分解与钙硅渣的生成,在136 ℃反应1 h后二氧化硅总反应率可达43.06%;在铝酸钠溶液中加入碳酸钠,可能因"协同效应"而促进原硅酸钙的分解;铝酸钠溶液苛性比变化对原硅酸钙的分解影响不明显.随着纯铝酸钠、碳酸钠和氢氧化钠溶液浓度的升高,原硅酸钙的Zeta电位绝对值增大,其原因可能是溶剂化层相应的Al(OH)4-,CO32-和OH-含量增多,有利于原硅酸钙的分解.  相似文献   

7.
聚羧酸系减水剂对水泥水化产物的影响   总被引:1,自引:0,他引:1  
为了研究聚羧酸系减水剂与水泥水化产物间的作用机理,利用差示扫描量热仪研究了减水剂对水泥水化产物组成的影响;采用化学合成法制备出水化硅酸钙,在合成过程中分别掺入聚羧酸系或萘系减水剂,对合成的水化硅酸钙进行扫描电镜分析、核磁共振测试和傅里叶红外光谱分析.结果表明:与萘系减水剂相比,聚羧酸系减水剂促进了水泥的水化,使水泥石中水化硅酸钙凝胶及氢氧化钙的生成总量增大;聚羧酸系减水剂可以减小水化硅酸钙的颗粒尺寸,使其聚合度增大;减水剂能促使水化硅酸钙中的硅氧四面体聚合度增加,且聚羧酸系减水剂的增强效果优于萘系减水剂.  相似文献   

8.
以Na_2Si O_3·9H_2O和CaO为原料,采用水热合成法通过控制反应时间合成了不同结晶度的硅酸钙产品.利用XRD和SEM等技术手段对合成样品的结晶状态进行表征,并利用自组装过滤性能测试装置对合成样品的过滤性能进行分析.研究了硅酸钙类材料结晶状态对其过滤性能的影响.结果表明,在200,℃条件下,经过8,h的合成反应结晶过程基本完成,反应的历程为:C—S—H凝胶→结晶C—S—H→硬硅钙石晶体.随着反应时间的延长,硅酸钙产品的晶体结构由团絮状向纤维状结构转化.4,h样品过滤性能最好,其平均过滤速度比结晶过程完成时提高了40%,,滤饼含水率下降了4%,.  相似文献   

9.
采用3Ti/Si/2C单质粉体为原料,进行机械合金化,以合成Ti3SiC2粉体.研究了Al和过量Si对机械合金化合成Ti3SiC2的影响.研究结果表明,机械合金化单质混合粉体,会诱发自蔓延反应.反应后产生大量坚硬的颗粒状产物.机械合金化3Ti/Si/2C粉体,会产生组成相为TiC、Ti3SiC2、TiSi2和Ti5Si3的粉体与颗粒产物.添过量Si并不会促进机械合金化反应合成Ti3SiC2.添适量Al可消除硅化物,明显促进反应合成Ti3SiC2.采用3Ti/Si/2C/0.15A1粉体作原料时,颗粒产物中Ti3SiC2含量最高,为92.8wt%;而采用3Ti/Si/2C/0.20A1粉体作原料时,粉体产物中Ti3SiC2含量最高,为61.9wt%.  相似文献   

10.
高密度氧化铟锡(ITO)靶材的制备研究   总被引:1,自引:0,他引:1  
 以水热合成的2种不同粒径(70±8)nm和(40±6)nm单分散ITO粉末为原料,对原料粉体粒径分布、冷等静压成型压力、烧结温度和时间等与靶材烧结密度之间的关系进行了研究.当2种粒径原料按7:3质量比混合均匀,成型压力为250MPa,成型坯体经1300℃预烧1.5h和在1400℃烧结1h后可以得到相对密度大于99%的高密度、高纯度ITO靶材.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
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   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

18.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
赵英华 《科技信息》2008,(12):219-220
0.Preface China has long been boasting of its colorful and immense culture which comprises of Taoism,Confucianism and Buddhism.The interwoven influence among the religions on Chinese way of thinking,on the nation's behavior in their social life throughout the long history is beyond list.  相似文献   

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