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为更有效利用燃煤电厂两大工业固体废弃物:粉煤灰及原状未煅烧脱硫石膏,进一步揭示粉煤灰-未煅烧脱硫石膏体系胶凝性能产生机制,采用NaOH溶液与水泥对其活性进行激发.80℃条件下养护7d后测定试件抗压强度,并分析水化产物的矿物组成.试验发现,在用水泥作为碱性激发剂时,适量脱硫石膏的存在对强度有较大的促进作用;但脱硫石膏的用量要适宜,用量过高,钙矾石数量增多,会引起体积稳定性的降低;NaOH作为碱性激发剂,无法使免煅烧脱硫石膏-粉煤灰胶凝体系形成有效强度,表明体系中足够的氧化钙是最终形成有效强度的重要保证. 相似文献
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将燃煤电厂的2大固体废弃物烟气脱硫石膏和粉煤灰变废为宝,研制出绿色环保的免煅烧脱硫石膏-粉煤灰复合胶凝材料.采用八通道热导式等温量热仪,通过研究单掺激发剂:氧化钙、硫酸铝、硅酸钠及三乙醇胺对脱硫石膏-粉煤灰复合胶凝材料的水化放热影响,得出各激发剂单独作用时胶凝材料的活性激发规律.在此基础上,通过正交试验得到脱硫石膏-粉煤灰复合胶凝材料中三种激发剂最佳配比:CaO为10%,Al2(SO4)3为7%,Na2SiO3为0.3%,且影响复合胶凝材料反应放热量的主次顺序为:Al2(SO4)3>CaO>Na2SiO3. 相似文献
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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
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煅烧电解锰渣-粉煤灰复合掺合料的试验研究 总被引:2,自引:0,他引:2
将电解锰渣分别在300℃、600℃、700℃、750℃、800℃和850℃温度下煅烧,制得煅烧电解锰渣料,再将其与不同比例的粉煤灰配合制成煅烧电解锰渣-粉煤灰复合掺合料,利用化学成分分析、DTA和XRD图谱分析及强度测试,对各掺合料-水泥体系的水化性能进行了研究。研究表明:电解锰渣属工业副产品化学石膏,未经煅烧的电解锰渣无水化活性和胶凝性,经一定温度煅烧后,具有较好的脱水石膏活性和火山灰活性,煅烧电解锰渣对粉煤灰-水泥体系有较好的强度激发作用,选择适宜的锰渣煅烧温度和掺入量可制得性能良好的复合掺合料。 相似文献
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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
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
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研究了由煅烧脱硫石膏与活性铝矿物制备的复合矿物外加剂,分析了它的组成对胶砂性能的影响及复合矿物外加剂替代的水泥种类对脱硫石膏与活性铝矿物复合效应的影响,确定了选用何种活性铝矿物配伍最好及脱硫石膏与活性铝矿物的最佳配伍比例;利用该比例的复合矿物外加剂配制不同强度等级的混凝土,对该体系的和易性、强度及收缩性能进行了研究.结果表明,脱硫石膏与非晶化程度较高的活性铝矿物配伍比例为3∶7时,该复合矿物外加剂活性指数最高,且对胶砂体系安定性没有不良影响,但对胶砂流动性略有影响;该复合矿物外加剂适于配制强度等级低于C60的混凝土,且混凝土中脱硫石膏与活性铝矿物的复合效应在一定程度上抑制了混凝土的收缩. 相似文献
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研究了碱、石膏、石灰和温度对粉煤灰火山灰活性的激发作用.结果表明,粉煤灰不具有自硬性,碱、石膏和石灰对粉煤灰火山灰活性有很强的激发作用. 相似文献
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《粉煤灰》2015,(4)
利用自制SFA防水剂及自配粉煤灰活性掺合料对生产砌块用脱硫石膏进行复合防水改性,研究了不同掺量粉煤灰活性掺合料对脱硫石膏标准稠度用水量、凝结时间、2h、28d强度及软化系数的影响,分析了外掺SFA防水剂和内掺粉煤灰活性掺合料对石膏试样强度与耐水性能的协同作用机理。结果表明:当外掺9%SFA防水剂、内掺30%粉煤灰活性掺合料量时,脱硫石膏试样的性能较优且适宜石膏砌块的生产工艺;SFA防水剂形成的不溶性阻水膜和粉煤灰活性掺合料水化形成的溶解性小的水化产物包覆在石膏结晶体表面或填充于石膏晶体间隙中,相互交叉共生,降低其溶解性,提高其结构密实度,有效改善石膏的耐水性和后期强度。 相似文献
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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
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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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
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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Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US
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
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中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2009,37(3)
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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中蓝晨光化工研究院《塑料工业》编辑部 《塑料工业》2007,35(3):1-25,67
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