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1.
钢渣及脱硫石膏-粉煤灰复合胶凝材料的改性研究   总被引:4,自引:0,他引:4  
研究了单掺钢渣对脱硫石膏-粉煤灰复合胶凝体系的影响.在引入钢渣的基础上,用复掺矿物外加剂水泥与石灰的方法对复合胶凝体系改性;并在此基础上,探讨了传统的碱激发与硫酸盐激发对该复合胶凝体系的影响,选取的化学激发剂有Na2SO4、CaCl2、Al2(SO4)3·18H2O、KOH.用XRD与SEM对较优配比的试样各龄期水化产物种类及形貌进行观测,在此基础上,对复合胶凝体系的水化反应及其进程进行分析.最后,对较优配比的复合肢凝材料的各项基本性能进行检测,结果显示,该复合胶凝材料性能优异.  相似文献   

2.
粉煤灰-脱硫石膏-矿渣复合胶凝材料性能初步研究   总被引:1,自引:0,他引:1  
以脱硫石膏和粉煤灰作为矿渣粉的激发剂和填料,制备成复合胶凝材料。研究了脱硫石膏和粉煤灰的掺加量对复合胶凝材料的浆体流动性能和硬化体力学强度进行了研究,发现流动性能随着粉煤灰掺加量的降低而下降,3d强度随着脱硫石膏的掺加量的增大而下降,7d强度则当脱硫石膏掺加量为20%时强度最高。同时还研究了3种常用碱激发剂NaOH、KOH和Na2SiO3对其流动性能和力学强度的影响。NaOH、KOH对流动性能的作用相似,随着加入量的增大而增大,而Na2SiO3则相反。3d强度随NaOH和KOH的掺量增大而增大,14d强度相反;Na2SiO3的3d激发作用不明显,14d强度则低于不掺入任何其他激发剂时的强度。  相似文献   

3.
崔孝炜  倪文  狄燕清 《硅酸盐通报》2018,37(4):1411-1417
为了促进钢铁冶金渣的高附加值应用,以钢渣、矿渣和脱硫石膏为原料制备胶凝材料,研究了不同掺量CaO或Na2SO4对胶凝材料的化学活化作用,并利用XRD、SEM对掺入激发剂胶凝材料的水化产物进行了分析.结果表明,掺入少量CaO或者 Na2SO4的胶凝材料净浆试块早期抗压强度会有一定的提高,后期强度变化不大;但当Na2SO4掺量超过2%时,净浆试块的抗压强度会降低.掺入激发剂对胶凝材料的水化产物种类不会造成影响,其水化产物主要包括钙矾石(AFt)、水化硅酸钙(C-S-H)凝胶和氢氧化钙(CH).  相似文献   

4.
施惠生  郭晓潞  张迪 《水泥》2010,(12):1-4
以钢渣、粉煤灰等固体废物,掺加少量的普通硅酸盐水泥、脱硫石膏,辅以适量化学激发剂,研制开发新型复合胶凝材料。试验表明,少量水泥能够有效地激发出钢渣-粉煤灰体系潜在的活性,单掺水泥的钢渣-粉煤灰体系最优配比为:钢渣/粉煤灰=6:4,水泥掺量为15%;对于复掺水泥和脱硫石膏的钢渣-粉煤灰体系来说,最优配比为钢渣/粉煤灰=6:4,水泥掺量为15%,脱硫石膏掺量为10%。合适的化学激发剂可以较好地提高复合胶凝材料的性能,复合胶凝材料在自然养护的条件下比标准养护条件下强度增长更快。  相似文献   

5.
矿渣及脱硫石膏-粉煤灰复合胶凝材料的试验研究   总被引:3,自引:0,他引:3  
吴敏  施惠生 《水泥》2008,(2):1-6
研究了不同的煅烧温度及保温时间对脱硫石膏-粉煤灰新型复合胶凝体系抗压强度的影响.在此基础上引入矿渣,研究矿渣及其掺量时脱硫石膏-粉煤灰复合胶凝体系的影响,并通过掺加矿物激发剂和化学激发剂对其改性.对较优配比的复合胶凝材料进行XRD与SEM研究,分析了其水化产物的成分与形貌.最后,对复合胶凝材料的基本性能进行检测.结果显示,适当的脱硫石膏的煅烧温度与保温时间、适宜掺量的矿渣、矿物激发剂与化学激发剂均能提高复合胶凝体系的强度;经改性的复合胶凝材料具有较好的性能.  相似文献   

6.
从城市生活垃圾焚烧飞灰在水泥混凝土材料领域中的资源化利用角度出发,采用比强度分析方法试验研究了飞灰的胶凝活性,探讨了化学激发剂对飞灰-水泥复合胶凝体系早期强度的活性激发以及相关的机理。结果表明:飞灰早期胶凝活性较低,尤其当掺量高于20%后,表现十分明显。分别掺入1%~3%的CaSO4,KAl(SO4)2,Al2(SO4)3和Na/SiO3的化学激发剂后,浆体的早期抗压强度明显提高,激发效果显著,但随龄期的延长,激发效果减弱。  相似文献   

7.
脱硫石膏-粉煤灰复合胶凝材料基胶砂试验研究   总被引:3,自引:0,他引:3  
脱硫石膏和粉煤灰混合后,在水泥、石灰、复合激发剂的作用下,可制备成一种新型复合胶凝材料。通过试验,在对水泥、激发剂及其最佳掺量的优选的基础上确立复合胶凝材料基本比例关系。结果表明,脱硫石膏与粉煤灰的最佳配比为2:3;水泥掺量对复合胶凝材料基胶砂强度影响明显,强度随水泥用量增加而增大;适宜用量的激发剂有助于提升强度。  相似文献   

8.
脱硫石膏-粉煤灰复合胶凝体系强度的改性研究   总被引:1,自引:0,他引:1  
脱硫石膏是燃煤电厂、炼油厂等排放的二氧化硫采用脱硫净化工艺技术处理所得的一种工业废石膏。研究了脱硫石膏不同的煅烧温度及保温时间对脱硫石膏-粉煤灰新型复合胶凝体系抗压强度的影响,并在此基础上采用矿物激发剂与化学激发剂对该复合体系进行改性,结果显示:适当的脱硫石膏煅烧温度与保温时间、适宜掺量的矿物激发剂与化学激发剂均能提高复合胶凝体系的强度。因此,这些方法郜是改善脱硫石膏-粉煤灰复合胶凝材料性能的有效措施.  相似文献   

9.
以原状脱硫石膏、粉煤灰、矿渣作为基本材料,运用正交试验研究了由NaOH、生石灰和水泥组成的复合碱性激发剂对于原状脱硫石膏-粉煤灰-矿渣复合胶凝材料基本力学性能的影响,确定了NaOH、生石灰、水泥的最佳掺量.在此基础上,研究了不同植物纤维、水胶比、减水剂对复合胶凝材料基本力学性能的影响,确定了纤维石膏基复合墙材的最佳配比.试验结果表明:NaOH、生石灰、水泥的最佳掺量分别为0.5%,8%,10%,该复合墙材选用苎麻纤维和萘系减水剂为宜,最佳掺量分别为2%和1%,最佳水胶比为0.38,所有组分均在脱硫石膏、粉煤灰和矿渣质量和的基础上按质量比外掺.  相似文献   

10.
黄科  马玉玮  郭奕群  李兆恒 《硅酸盐通报》2015,34(10):2769-2774
研究了碱激发剂中SiO2与Na2O含量对碱激发粉煤灰/矿渣复合体系凝结时间和抗压强度的影响,并采用扫描电镜对样品的微观形貌进行表征,研究结果表明:碱激发粉煤灰/矿渣的凝结时间在15~705 min总体而言,激发剂中Na2O含量越高(>4%),样品的凝结时间越长;SiO2含量越高(>2%),样品的凝结时间越短.激发剂中SiO2含量为4%,Na2O含量为6%时,样品抗压强度增幅最大.扫描电镜(SEM)结果表明,SiO2含量越高,材料结构越致密;当Na2O含量高于6%时,材料结构变松散.颗粒较细,比表面积较大的粉煤灰碱激发活性高,样品的抗压强度也越高.  相似文献   

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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   

13.
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

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In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  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   

19.
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   

20.
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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