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为加强各省市水泥协会及大型水泥企业办公室之间的工作联系,增进相互间的沟通、交流与合作,充分发挥好行业协会的双向服务功能,用创新的思维,把协会办成会员之家。根据中国水泥协会提议,在本次秘书长联席会议上,经过认真讨论修订,一致同意《关于中国水泥协会与各省市水泥协会、大型水泥企业加强工作合作的建议书》。 相似文献
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以标准石灰率=90,硅率=2.0,铝氧率=1.7的实验室熟料作为基准试样,在煅烧前逐级地加入TiO_2一直到3.9%作为第一组,以逐级地加到1.5%的TiO_2取代当量的SiO_2为第二组。通过TiO_2的掺入对煅烧产生有利的影响。在熟料的显微镜探针检验中,发现钛以不同的程度加入到4个主要相中,阿利特结晶为单斜晶系的变体MⅡ;贝利特是β型的;铝酸钙成为立方形变体。阿利特结晶尺寸,随着TiO_2从0提高到1.5%而成倍地大约从20微米增大到40微米。提高TiO_2的含量会成正比例地增加贝利特含量而使阿利特含量减少(TiO_2从0到1%大约引起硅酸盐含量10%的变化)。相反,铝酸盐和铁酸盐含量却基本上没有变化。硅酸钙含量的可观的变化证明加入的Ti部分取代了硅酸盐中的Si,此外作为固溶态的CaO吸收到贝利特中是可能的。也是在CaO-Al_2O_3-Fe_2O_3-SiO_2的四元系统中的变化(无变点的变化),通过Ti的存在能够阐明相含量的变化。水泥(布氏比面积3780±40厘米~2/克)由于TiO_2含量的提高而成为深灰色。强度(不是2天强度)由于大约1%的TiO_2成分而有所提高。虽然,阿利特含量减少了,并且标准石灰率下降(Ti在分母中必须考虑到),但却出现了强度的增长(<10%),这可以通过高强度发展的含钛的阿利特来说明。水化热的发展与强度发展相似,符合原来的设想。TiO_2延缓了第一天的水化作用而对于以后的令期则起加速作用。初凝时间由于TiO_2含量的提高而延迟,对于含硫酸盐水泥的抵抗能力,相反地没有明显的影响。 相似文献
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波特兰水泥的水化机理 总被引:1,自引:0,他引:1
泰勒(H.F.W.Taylor)教授是英国阿伯丁(Aberdeen)大学化学系主任,国际知名化学家。他应建材部建筑材料科学研究院邀请,于一九八○年三月十七日至四月八日来我国访问和讲学。讲学内容由孙国匡同志翻译、整理,座谈内容由孙国匡同志翻译、席耀忠同志整理。由吴中伟、薛君玕同志审校。 相似文献
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2011年9月13日,中国橡胶工业协会与橡胶谷有限公司建立战略合作关系的签约仪式在橡胶谷举行。中国橡胶工业协会副秘书长徐文英代表中国橡胶工业协会,橡胶谷管委会副主任、橡胶谷有限公司总经理张焱代表橡胶谷在合作协议书上签字。中国橡胶工业协会会长范仁德.青岛市四方区副区长蔡全记,青岛科技大学副校长王文哲,中橡协胶管胶带分会秘书长李鸿,四方区科技局局长张永伟,青岛科技大学科技处处长郭仲聚,橡胶谷有限公司副总经理路建平、周杭生、郭磊等领导出席了签约仪式。 相似文献
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为了研究磷酸钾镁水泥基材料与硅酸盐水泥混凝土的粘结性能,测试了磷酸钾镁水泥基材料浆体的抗压强度,同时测试了磷酸钾镁水泥基材料浆体与不同状态的硅酸盐水泥砂浆的粘结抗折强度和收缩变形,分析了磷酸钾镁水泥基材料硬化体的物相组成、微观形貌以及与硅酸盐水泥砂浆基体的粘结界面结构.结果表明:双掺粉煤灰和石灰石粉,使磷酸钾镁水泥基材料硬化体的结构更完善,抗压强度、粘结抗折强度和体积稳定性均明显提高.保持硅酸盐水泥砂浆基体的龄期大于7d和气干含水状态,磷酸钾镁水泥基材料与硅酸盐水泥砂浆界面的结合力加强,粘结抗折强度明显提高. 相似文献
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用微波在1370℃,1400℃,不同生料组成下煅烧了硅酸盐水泥,并与在1450℃的电炉煅烧进行了比较.结果显示:微波煅烧比电炉煅烧的温度至少降低50℃,煅烧时间减少约70%.微波煅烧(1400℃,10min)水化活性优于电炉煅烧(1450℃,30min),强度也提高.同种生料,两种不同煅烧模式得到的熟料中,其四大矿物(C3S,C2S,C3A,C4AF)是相同的,阿利特相结构都属于Ⅲ型和Ⅰ型单斜晶系,但微波煅烧的熟料中硅酸盐矿物(C3S+C2S)总含量提高了约10%,晶体的尺寸较小且比例较高,中间相(C3A+C4AF)的含量降低了约10%,黑色中间相的尺寸有增大趋势.结果还表明,适宜的组成有利于微波烧成硅酸盐水泥,并且其矿物形成过程也不同于电炉煅烧. 相似文献
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Analytical Study of Pure and Extended Portland Cement Pastes: I, Pure Portland Cement Pastes 总被引:1,自引:0,他引:1
A range of portland cement pastes were examined by X-ray diffraction, analytical electron microscopy, thermogravimetry, and CO2 analyses. Quantitative estimates of the phase compositions of the pastes and of the chemical compositions of the individual phases within them were obtained, and mass balance calculations were done for each oxide component to test the mutual consistency of the results. As a further test, thermo-gravimetric curves were calculated from the phase compositions and compared with those found experimentally. Volume percents of phases, porosities, and related quantities were also calculated. For a typical cement cured for 28 d in a sealed container at a water, cement ratio of 0.5 and equilibrated at 11% rh, the calculated volume percents are as follows: unreacted clinker phases, 11; C-S-H, 29; Ca(OH)2 , 11; AFm phase, 9; CaCO3 , 1; pores, 39. 相似文献
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Experimental data on the interfacial reaction between portland cement clinker and molten coal ash at 1400° to 1500°C are consistent with a mechanism involving diffusion in the melt as the rate-controlling step. The formation and growth of well-defined zones between the reactants are characteristic of the reaction. Equations were solved for diffusion with two moving interfaces. On the basis of these equations and data from the lime-alumina-silica phase equilibrium diagram, the diffusion coefficient for CaO in the interstitial melt in the clinker is about 5±10-6 cm2 /s at 1500°. The results imply that the clinkering reaction in the burning of portland cement clinker is also controlled by diffusion in the melt. 相似文献
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Adsorption of Admixtures on Portland Cement 总被引:1,自引:0,他引:1
B. BLANK D. R. ROSSINGTON L. A. WEINLAND 《Journal of the American Ceramic Society》1963,46(8):395-399
In an attempt to verify theories on the effect of admixtures on portland cement, the adsorption isotherms for calcium lignosulfonate and salicylic acid on cement have been determined. The adsorption isotherms for these compounds on 3CaO·SiO2, 2CaO·SiO2, 3CaO·Al2O3, and 4CaO·Al2O3·Fe2O3 and on a mixture of these components in the ratio 60/25/5/10 have also been determined. Adsorption isotherms were determined at 24°C by a spectrophotometric method, using a Beckman DU spectrophotometer. As a check on the method, previous work of Ernsberger and France on the adsorption of lignosulfonates on portland cement was repeated and their results were confirmed. Results indicate that in aqueous solution the constituents of portland cement mainly responsible for the adsorption of the two compounds studied are the hydration products of 3CaO·Al2O3 and 4CaO·Al2O3·Fe2O3. Salicylic acid adsorption on cement compounds does not fit the Langmuir form. However, adsorption of salicylic acid on type I portland cement, for equilibrium concentrations above 0.005%, fits the form. Calcium lignosulfonate adsorption on type I portland cement, 3CaO·SiO2, 2CaO·SiO2, and partly on 4CaO·Al2O3·Fe2O3 fits the Langmuir form. Adsorption isotherms of salicylic acid on the major cement compounds were determined from ethyl alcohol solution to eliminate the hydration of the compounds occurring in aqueous solution. The adsorption of salicylic acid on the materials studied was found to be in the order: The effect of water on the adsorption of salicylic acid from ethyl alcohol solution was studied. It was found that the smaller the amount of water present, above a minimum value, the greater was the adsorption on 3CaO·Al2O3, 2CaO·SiO2, and 3CaO·SiO2. In the case of 4CaO·Al2O3·Fe2O3 the adsorption of salicylic acid was proportional to the amount of water present at all concentrations studied. It is observed in certain cases that it is probably not surface adsorption but a compound formation with salicylic acid. 相似文献
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中热硅酸盐水泥的研制 总被引:1,自引:0,他引:1
新疆和静天山水泥有限责任公司位于新疆小三峡工程东南80km处,因开都河上阶梯电站的建设,需要大量的中热硅酸盐水泥,而和静公司无论在地理、资源、设备装备都具有优势,具备生产中热水泥的条件。1原燃材料的选择根据中热硅酸盐水泥的标准要求,结合本地的资源状况,原燃材料选择情 相似文献
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试验研究了一种新的硅酸盐水泥熟料煅烧方法:先用电炉将生料加热到一定温度后再用微波进行强化烧成,实验发现在较低的电加热温度下(1000-1200℃左右),再使用微波强化煅烧1-2min即可烧成熟料,熟料中f-CaO的质量分数在1%-2%之间;人微波炉的物料温度越高,微波加热需要的时间越短,加热到1300℃的物料,微波加热只需40s,熟料中f-CaO的质量分数可降至0.65%,试验证明,采用新的煅烧方法可大幅度提高硅酸盐熟料形成速度;Fe2O3对熟料的微波烧成有很好的促进作用,熟料的XRD图谱显示,熟料矿物的组成和XRD特征衍射与传统方法烧成的熟料一致。 相似文献