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1.
研究粉煤灰掺量对碱激发矿渣砂浆的凝结时间、抗压强度、化学收缩和自收缩的影响因素和影响规律.结果表明,加入粉煤灰不仅能有效改善碱激发矿渣砂浆凝结快,收缩变形大的问题,同时也能够解决碱激发粉煤灰砂浆在常温条件下早期强度低和强度发展缓慢等问题.配比不同掺量的粉煤灰,以寻求最佳的掺量,在保证碱激发矿渣砂浆强度的同时提高减缩效果.  相似文献   

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朱春启  杨春保 《四川水泥》2013,(Z1):103-105
以粉煤灰、矿渣为基本原料,以水玻璃为碱激发剂,研究了在实验条件下制备粉煤灰—矿渣基水泥的碱激发规律。结果表明,粉煤灰、矿渣的相对掺加量、水玻璃的掺量及模数、熟料、Na2SO4、CaO掺加量对强度都有显著的影响。  相似文献   

3.
影响碱—粉煤灰—矿渣基胶凝材料性能因素的探讨   总被引:16,自引:0,他引:16  
该文论述了影响碱-粉煤灰-矿渣基胶凝材料性能的主要因素,就粉煤灰矿渣比、碱的类型及掺量、粉煤灰的机械活化和碱激发的复合作用、早强剂及晶种等因素进行了系统的研究。  相似文献   

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复合碱组分对矿渣粉煤灰碱胶凝材料性能的影响   总被引:8,自引:0,他引:8  
研究了复合碱组分NaOH、Na2 CO3 对矿渣粉煤灰碱胶凝材料性能的影响。结果表明 :与单掺NaOH相比 ,采用复合碱组分激发矿渣粉煤灰体系 ,强度更高 ,凝结时间更趋合理。另外 ,还对水化产物进行了探讨  相似文献   

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碱激发胶凝材料是以工业固体废弃物为原料制备的一种绿色无机胶凝材料,具有良好的力学性能与耐久性能。粉煤灰因其独特的球体微观结构与其他固废微粉存在本质区别,因此粉煤灰在碱激发胶凝材料体系中的作用机理亟待研究。以矿渣与粉煤灰为原料,利用碱激发剂制备胶凝材料,并对材料进行抗压强度测试,最后采用XRD、FTIR和SEM探究碱激发矿渣/粉煤灰体系的水化反应机理,研究粉煤灰对矿渣/粉煤灰体系的作用机理。结果表明:外掺3%(质量分数)NaOH作为碱激发剂,水固比为0.4时,随粉煤灰掺量减少,抗压强度呈现先上升后下降的趋势;m(矿渣):m(粉煤灰)为4:1时,28 d抗压强度达到峰值(37.1 MPa)。粉煤灰颗粒在不同龄期形成具有不同反应程度与尺寸的嵌入式微观结构,对材料力学性能起到不利影响;但粉煤灰的活化程度随龄期延长逐渐变大,对后期强度发展有持续贡献。碱激发矿渣/粉煤灰体系水化产物中含有Friedel盐、托贝莫来石、钙矾石、C-S-H/C-A-S-H凝胶,以及粉煤灰中残留的α石英相。随粉煤灰掺量增加,托贝莫来石生成量减少,钙矾石向Friedel盐转变,钙矾石生成量减少,Friedel盐生成量增多。  相似文献   

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伍勇华  胡宇博  南峰  何娟  陈畅 《硅酸盐通报》2019,38(4):1166-117
为了研究粉煤灰对碱激发矿渣胶凝材料耐盐酸腐蚀性能的影响,对不同粉煤灰掺量下碱激发矿渣砂浆在pH=1的盐酸环境中浸泡14 d、28 d和60 d后的外观、质量损失、腐蚀深度、抗压强度和耐蚀系数进行了研究,通过X射线衍射和化学滴定方法对其机理进行了分析.结果表明:碱激发矿渣砂浆在盐酸溶液中浸泡后表面被严重腐蚀,质量与强度损失均很大.粉煤灰的掺入使试块表面被腐蚀情况明显变好,质量与强度损失也明显减少,但粉煤灰的掺入会降低碱激发矿渣砂浆的强度,增大其腐蚀深度.XRD与化学分析的结果表明碱激发粉煤灰中可被盐酸溶出的物质含量较少,因而掺入粉煤灰可以提高碱激发矿渣胶凝材料的耐盐酸腐蚀性能.  相似文献   

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固体碱激发制备碱-矿渣-高钙粉煤灰水泥的研究   总被引:16,自引:1,他引:15  
研究了采用固体碱激发制备碱 -矿渣 -高钙粉煤灰水泥的方法途径。结果表明 :在碱激发剂最佳掺量条件下 ,调整矿渣与高钙粉煤灰的配比 ,可制备出 32 5号~ 5 2 5号的碱 -矿渣 -高钙粉煤灰水泥。该水泥生产成本低、性能优良 ,是一种具有发展前景的绿色环保节能建材。  相似文献   

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本文在碱激发粉煤灰矿物聚合物的基础上,研究了在粉煤灰中掺人适量硅灰形成碱激发硅灰-粉煤灰基矿物聚合物的性能.结果表明,当碱激发剂Na2SiO3·9H7O用量20wt%,硅灰掺量10wt%时,碱激发硅灰-粉煤灰基矿物聚合物在室温养护下抗压强度达到58.83 Mpa,较不掺硅灰的矿物聚合物强度提高了72%.X衍射分析表明,形成的矿物聚合物为无定形矿物相,SEM微观形貌分析表明,掺入硅灰后,矿物聚合物的微观结构更加致密,其强度大幅度提高.  相似文献   

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为探究矿渣、粉煤灰及电石渣的资源化利用,以电石渣作为碱激发剂,研究了矿渣-粉煤灰复合胶凝材料的水化产物组成及强度特征。采用X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、热重-差示扫描热(TG-DSC)、扫描电子显微镜及能谱(SEM-EDS)等微观测试技术,分析了复合胶凝材料的晶体结构、热化学性质以及微观形貌等特性,研究了电石渣激发矿渣-粉煤灰复合胶凝材料的作用机制。结果表明:电石渣作为碱激发剂时能为矿渣-粉煤灰复合胶凝材料提供初始水化所需要的强碱环境,驱动矿渣和粉煤灰发生水化反应。随着矿渣掺量的增加,复合胶凝材料的强度发展呈先增加后减小的变化趋势,在粉煤灰与矿渣掺量质量配比为4∶6、外掺电石渣质量分数为4%时,复合材料浆体经4 d常温养护+32 h高温蒸汽养护后抗压强度达到25.9 MPa;矿渣-粉煤灰复合胶凝体系中水化产物分布不均,主要组成为水化硅酸钙、水化铝酸钙、水化硅铝酸钙等凝胶。电石渣作为矿渣-粉煤灰体系的碱激发剂使用时效果良好。  相似文献   

10.
为实现滩涂淤泥质土和工业废料资源化利用,定量优化地聚物固化淤泥质土的关键因素,基于Box-Behnken响应面法对碱激发矿渣-粉煤灰基地聚物固化淤泥质土的配合比进行优化,选取矿渣掺量、碱激发剂模数和碱激发剂掺量为主要考察因素,并结合宏观性能和微观形貌进行固化机理分析。结果表明:固化土最优配合比为矿渣掺量86.5%(质量分数),碱激发剂模数0.84,碱激发剂掺量7.3%(质量分数),此时固化土7和28 d无侧限抗压强度分别为5 823和7 027 kPa,预测值与实际值误差较小,所建立的模型与实际数据拟合准确可靠;固化土的水化产物主要为无定形凝胶水化硅铝酸钙(C-(A)-S-H)和硅铝酸盐聚合物(N-A-S-H),可增强土体的密实程度和骨架结构,以此提高固化土的强度。本研究为碱激发地聚物固化淤泥质土提供了理论依据和实验基础。  相似文献   

11.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

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收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

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Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.  相似文献   

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