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1.
研究了无限箭图的Clebsch-Gordan问题及其表示环,利用箭图的特征表示推导出A∞型箭图的Cleb-sch-Gordan公式,证明了A∞型箭图的表示环是An型表示环的正向极限.  相似文献   

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以纯化学试剂配料 ,研究ZnO及ZnO与CaF2 复合对C3S和C4A3S矿物形成及共存的影响。结果表明 ,一定量的ZnO可改善配合料的易烧性 ,促进C3S及C4A3S矿物的形成 ,有利于其在熟料中的共存 ;当同时添加ZnO与CaF2时 ,效果更显著  相似文献   

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以纯化学试剂配料, 研究了 Mg O 对 C3 S C2 S C4 A3 S C4 A F Ca S O4 五元系统中 C3 S和 C4 A3 S两种矿物形成的影响。结果表明,掺加适量的 Mg O 可促进 C3 S及 C4 A3 S矿物的形成,有利于其在熟料中的共存; Mg O 可显著降低 C3 A 的形成量并可增加 Si O2 在中间相中的固溶量。  相似文献   

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以纯化学试剂配料 ,研究了CaF2 对C3S和C4 A3S矿物形成及共存的影响。结果表明 ,掺加适量的CaF2 可改善配合料的易烧性 ,促进C3S及C4 A3S矿物的形成 ,有利于其在熟料中的共存  相似文献   

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通过X线衍射仪(XRD)、扫描电子显微镜(SEM)、能谱仪(EDS)和透射电子显微镜(TEM)等现代分析技术以及选择性萃取的方法对利用粉煤灰煅烧的硅酸二钙(C2S)-无水硫铝酸钙(C4A3)水泥熟料矿物组成和微结构进行研究。结果表明:熟料主要矿物为正交和立方晶型的C4A3以及β和α'晶型的C2S。C4A3的2种晶型均存在调制结构。此外熟料中还存在少量钛酸钙(CT)、钙铝黄长石(C2AS)以及MgO。熟料结构疏松多孔,C2S和C4A3结晶均较为细小。  相似文献   

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An Agilent 6890N GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5—C13 hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5—C13 compounds on a PONA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograms (MID and full scan) could be obtained at the same time. The retension time differences of nC6—nC13 alkanes between GC and TIC were in the range of 0.02—0.58 minutes. Totally 286 peaks have been assigned group compositions. Results on 8 typical oil samples from CNPC Key Laboratory Crude Oil Library showed that the characteristics of C6—C13 hydrocarbon group composition could be used in oil-oil correlation studies.  相似文献   

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本文采用X射线衍射分析方法,研究了影响C_(11)A_7·CaF_2稳定性的因素,结果表明C_(11)A_7·CaF_2在1450℃以内,能够稳定存在;Mgo,K_2O对C_(11)A_7·CaF_2稳定性没有影响;Na_2O、P_2O_5和CaO能与C_(11)A_7·CaF_2发生反应、分别生成少量NC_6A_3、Ca_5F(PO_4)_3和C_3A,但在硅酸盐水泥熟料的正常煅烧制度下,反应程度较低,对C_(11)A_7·CaF_2稳定性不大.熟料中铝酸盐相存在的形式,主要取决于氟在熟料中的分布,CaF_2掺量较低,温度超过1350℃,C_(11)A_7CaF_2消失,生成C_3A;CaG_2掺量较高时,温度高达1450℃,熟料中的铝酸盐相仍为C_(11)A_7·CaF_2,而不生成C_2A.  相似文献   

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将粉煤灰、石灰石和少量石膏配合制成生料,烧成以硅酸三钙和硫铝酸钙为主要矿物成分的早强熟料,再掺加40%左右的粉煤灰作为混合材料而磨成的水泥,标号能够达到325~425,早期强度较高。矿物形成过程的实验室研究和φ3.1/2.5×78米回转窑的试生产都证明,C_aO-SiO_2-Al_2O_3-Fe_2O_3系统中引入一定量的SO_3和少量的C_aF_2.硅酸三钙的形成温度可大幅度降低。同时,所形成的一定量的硫铝酸钙等矿物对早强是有利的。当石膏和粉煤灰的掺加量控制适当时,能制造出性能良好的水泥,可望成为一种应用广泛的新品种.  相似文献   

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Solvatochromism was observed in some solutions of C60 or C70, which was thought to arise from the formation of fullerene clusters[1—6]. This special type of solvato- chromism has aroused much interest because it has some potential applications in material science and sensor tech- nology. On the other hand, C60 or C70 can be made soluble in water by connecting it to various functional groups[7—20]. Those functionalized fullerenes not only have been found a number of important applicati…  相似文献   

12.
Relations among gauge functions, metrics and Hausdorff measures   总被引:1,自引:0,他引:1  
In this paper we discuss the relations among the doubling condition, equivalence of the Hausdorff measures and equivalence of metrics. We will show that H ρ,g1 and H ρ,g2 are equivalent for any compact metric space (X,ρ) if and only if g1 and g2 are equivalent gauge functions. Then, we prove that for given c∈(0,∞)\{1}, H ρ,g and H cρ,g are equivalent for any compact metric space (X,ρ) if and only if the gauge function g satisfies the doubling condition, where H ρ,g is the Hausdorff measure with respect to the metric ρ and gauge function g.  相似文献   

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该文分析了2种CCC(C_4A_3$-CaSO_4-CaO)体系在混凝土中的作用效果,揭示了掺入CCC体系的混凝土产生失水膨胀的原因。测试了2种CCC体系对混凝土工作性、抗压强度、自收缩和干燥收缩、水化热、XRD图谱的影响。CCC体系中的CaO组分由于制备阶段的死烧或低水胶比条件下水化过程受阻,不能在水化早期阶段完成水化;之后,非饱水条件下CaO通过原位反应产生膨胀,使得混凝土表现出失水膨胀现象。结果表明:CCC体系可有效补偿混凝土的自收缩和干燥收缩。研究结果揭示了CCC体系中组分活性与膨胀特性的关系。CCC体系制备过程中应避免对CaO组分的死烧;同时,低水胶比混凝土中应降低CCC体系的掺量。  相似文献   

14.
The controller designed according to classical or modern control theory will not satisfy the performance requirements when the controlled object in industrial field can not be described by exact mathematical model or the disturbance of the controlled system. In order to make the controlled system stable and having good performance, H∞ control theory was put forward to solve this practical problem. Taking the position of a rolling mill as the controlled object, it was rectified by optimal engineering way. Then, three different plans were put forward according to Bang-Bang control, LQ control and H∞ control, respectively. The result of the simulation shows that the controller designed according to H∞ method whose robust performance and ability to restrain colors disturbance is satisfactory.  相似文献   

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The paper reports investigation which have confirmed the relation between burningtemperature and formation of minerals,which exists in iron-rch fluornluminate cementIn order to burn iron-rich fluoraluminate cement at lower temperature,the SO_3 contentmust be controlled.  相似文献   

18.
Using Fuzzy Relations and GIS Method to Evaluate Debris Flow Hazard   总被引:3,自引:0,他引:3  
The study area, located in the southeast of Tibet along the Sichuan-Tibet highway, is a part of Palongzangbu River basin where mountain hazards take place frequently. On the ground of field surveying, historical data and previous research, a total of 31 debris flow gullies are identified in the study area and 5 factors are chosen as main parameters for evaluating the hazard of debris flows in this study. Spatial analyst functions of geographic information system (GIS) are utilized to produce debris flow inventory and parameter maps. All data are built into a spatial database for evaluating debris flow hazard. Integrated with GIS techniques,the fuzzy relation method is used to calculate the strength of relationship between debris flow inventory and parameters of the database. With this methodology,a hazard map of debris flows is produced. According to this map,6.6% of the study area is classified as very high hazard, 7.3% as high hazard,8.4% as moderate hazard,32. 1% as low hazard and 45.6% as very low hazard or non-hazard areas. After validating the results, this methodology is ultimately confirmed to be available.  相似文献   

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In this paper,the effects of various structural properties on the synchronization of coupled oscillators with local-world coupling configurations are investigated.It is found that for local world networks,the larger heterogeneity of the degree distribution,the enhanced interconnection of nodes,and the increased clustering do not improve the synchronizability of dynamical systems.On the con- trary,the increase of the maximum betweenness centrality appears to be responsible for the decrease of the synchronizability.  相似文献   

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