【正文】 鐵鋁酸四鈣的比例。IM值過高時，熟料液相的黏度增大，生料難燒，不利于擴散吸收其中的游離氧化鈣，最終導致游離氧化鈣偏高；IM值過低時，液相的黏度過小，物料的燒結(jié)范圍變窄，煅燒溫度更是不易控制；溫度低時會造成物料預燒不夠；溫度控制高時容易燒流結(jié)大塊，導致窯況的不易穩(wěn)定，最終也會導致游離氧化鈣含量的偏高。不過會導致C3S、C2S含量下降，強度下降，影響質(zhì)量。其結(jié)構(gòu)致密，晶體一般達10～20um，較大，往往成堆聚集分布，形成礦巢，熟料礦物并將其包裹在其中，且受雜質(zhì)離子的影響，使生成氫氧化鈣的反應很慢，通常要在加水3天以后才反應明顯，在水泥混凝土硬化較長一段時間后才水化完全。因為氧化鈣化合后又游離出來，故稱之為二次游離氧化鈣。適當提高水泥的粉磨細度，降低熟料中游離氧化鈣的含量，并提高fCaO的水化活性等均有利于改善游離氧化鈣對安定性的影響。因為熟料中三氧化硫除來源于煤外，還來源于原料，此分析不能作為理論成立，該結(jié)論不成立。相對于同種煤粉來看，粗顆粒煤粉要比細顆粒煤粉需要較長的燃燒時間，所以煤粉的細度變化將直接影響煤粉在預分解窯系統(tǒng)中的燃燒效率和窯的操作運行條件，從而最終影響到窯系統(tǒng)的生產(chǎn)能力和熱耗。有3天強度有上升趨勢。圖315中，～，B線窯28天強度是下降的，又開始增加。煤灰作為原料是熟料的一部分，煤中所帶的硫直接影響到所生產(chǎn)熟料的強度和生料的易燒性。當然，要是在無旁路放風的情況下，氯、鉀、硫、鈉不斷揮發(fā)、冷凝，如果硫堿比太低則會形成以碳酸堿為主的堅硬窯皮；如果堿和硫反應達到平衡后還有過剩的硫存在，那么過剩的硫在窯中循環(huán)也會引起結(jié)皮，其主要成分是硫硅酸鈣（2C2S?CaSO4）和硫酸鈣形成的致密層，且很難清除。 SO3含量(%)fCaO百分含量(%)圖316 A線窯熟料SO3含量與fCaO含量SO3含量(%)fCaO百分含量(%)圖317 B線窯熟料SO3含量與游離氧化鈣含量在圖316中，～，其游離氧化鈣含量呈上升趨勢，又開始下降；在圖317中，～，游離氧化鈣含量先上升，之后下降。4 結(jié)論(1)熟料中游離氧化鈣的百分含量與入窯生料的細度都基本成正相關(guān)量的關(guān)系，熟料中游離氧化鈣含量都隨生料細度的增大而增多。當硅率和鋁率相同的情況下，石灰飽和系數(shù)在一定范圍內(nèi)，游離氧化鈣含量會隨KH值的上升而上升，超出一定范圍后會有下降的趨勢。(5) 熟料中的游離氧化鈣含量隨SO3含量先增后降，但是影響不明顯。在畢業(yè)設(shè)計期間，郁老師提供給我許多鍛煉的機會，培養(yǎng)我獨立思考問題、解決問題以及將理論應用于實際的能力，在此論文完成之際，謹向郁老師表示崇高的敬意和誠摯的感謝，祝福郁老師及其家人身體健康、工作順利。四年的大學生活讓我豐富了見識，我相信在以后的工作中會對我產(chǎn)生深遠的影響。 Concrete Composites,1999,21:99104附錄外文資料An AFMSEM investigation of the effect of silica fume and fly ash on cement paste microstructureAtomic force microscopy (AFM) was used to observe particle shape and surface texture details of normal portland cement and supplementary cementing materials (silica fume,lowcalcium fly ash,and highcalcium fly ash).The latter maerials mixed with cement were examined after prolonged innovative information on particle shape and hydrated paste microstucture was microscopy techniques,such as scanning electron microscopy(SEM),cannot provide such detailed images and surface texture characteristics of the fine materials (especially silica fume )and of the product showed ,for the first time ,that silica fume particles are primarily posed of two plimentary parts(hemispheres or semicylinders).Nanosize particles were found in all relatively smooth product surface was observed in the hydrated cement hydrated surface of the additioncement pastes presented small spheroid bulges,giving an additional roughness as was measured by sufficient correlation of this microscopical quantitative information with macroscopical engineering and durability properties of cement products is also presented.For technical and economic reasons,new materials with pozzolanic and cementitious properties have been mixed with cement during the last these materials are industrial byproducts such as fly ash from coalburning electric power plants,slags from metallurgical furnaces,silica fume (or microsilica) from electric arc furnaces producing silicon and ferrosilicon alloys,and some naturally active materials such as volcanic activity is mainly due to te reaction of their active constituents with Ca(OH)2 produced from cement hydration(pozzolanic activity)and the formation of hydrated products with binding exact stucture and chemical formula of these products are still unknown.The detailed knowledge of cement paste microstructure is of great importance for the understanding and predictionof cement applications’ examination,optical microscopy,and scanning electron microscopy(SEM) have been extensively used in microstucture research of hardened cement paste and concrete,providing additional understanding of macroscopical microprobe analysis studies of hardened cement pastes have contributed to the positional characterization of hydration products and spatial energy microscopy(TEM) enables the identification and analysis of features on a significantly submicrometre ,these techniques most monly investiate specimens under high vacuum,and thus alteration of damage on microstructure morpology may ,some of these materials,such as silica fume,with a grain size distribution in the to range,are too small to be observed in detail by with stronger magnification capabilities would be very useful in these cases,as well in the better conception of the pure cement paste microstructure. By atomic force microscopy (AFM),a sharp tip is scanning over a sample surface and three dimensional images haveing resolution at nanometer level are obtained at atmospheric conditions (room temperature,humidity,and ambient pressure).AFM has been used to produce atomic resolution images of both conductors and the present decade,AFM has also been used in the study of cement surface microstucture,especially because surfaces can be imaged under aqueous solutions at normal has been applied to investigate the surface of alite alone and of alite covered with an organic admixture and has shown that the surface roughness of the alite decreased markedly after reaction with the organic was also used to investigate the early period of portland cement hydration ,and a membrane/osmosis model was bination of nuclear magnetic resonance(NMR)and AFM showed that the hydration rate is highly correlated with the roughness of the gel fly ash particles,AFM showed two types of spheres ,dark,large ones (approximately 100um)with numerous craters on their surface and clear,small ones (approximately 10 um)with smooth surface. In the present work ,AFM was used to observe particle shape and surface texture details of cement silica fume,fly ashes ,and hydrated micrographs of 1um1um were taken ,providing information on the particle shape of the additions and microstructure of the hydrated same materials were examined under SEM to obtain a general overview,and the parative use of these two methods(SEMAFM) is ,the correlation between the microstructure and the macroscopical engineering and durability properties of cement products is discussed. procedure and sample preparationThree typical cementitious and/or pozzolanic additions were examined