煤矸石颗粒群分布与煤矸石水泥活性的关系研究

本文将纯硅酸盐水泥、煤矸石按不同的粉磨时间序列处理成若干个不同颗粒群分布的试样,配制成一系列煤矸石硅酸盐水泥(煤矸石掺量均为30％),进行胶砂强度检验。采用灰色关联分析方法研究了煤矸石各粒径范围颗粒含量与煤矸石水泥强度的相互关系。结果表明:(1)煤矸石粒径在10μm以下的颗粒体积百分数与煤矸石水泥的强度均为正关联,而大于10μm的颗粒与煤矸石水泥的强度均为负关联,说明小于10μm的颗粒对强度增长有积极贡献;而大于10μm的颗粒对强度增长不利。(2)R-R分布表明:在煤矸石达到一定细度的条件下,宽分布试样有较多的小于10μm颗粒。     

水泥-粉煤灰的颗粒群匹配与其胶砂性能的关系研究

本文将某低钙灰试样经粉磨处理,以不同比例与一定细度的纯硅酸盐水泥进行匹配,制成一系列粉煤灰水泥试样。根据Dinger-Funk的数学模型可得出粉体最佳颗粒群分布(即堆积密度达最大时的分布),并通过水泥与粉煤灰激光粒度检测结果计算各粉煤灰水泥的实际颗粒群分布。运用灰色关联分析原理,考察各粉煤灰水泥试样的颗粒群分布与Dinger-Funk最紧密堆积颗粒群分布的相关性。同时,对各粉煤灰水泥进行标准稠度用水量以及胶砂强度测定。结果证明:当粉煤灰与水泥的匹配后的颗粒群分布与最紧密堆积的关联度较高时,相应的粉煤灰水泥标准稠度用水量较少,胶砂强度则较高。     

熟料和粉煤灰的颗粒尺寸分布与水泥性能的灰色关联分析

将不同比表面积的熟料和粉煤灰分别混合制得不同比表面积的粉煤灰水泥,分别测定粉煤灰水泥胶砂强度和熟料、粉煤灰的颗粒尺寸分布.运用灰色系统原理分别就熟料和粉煤灰的颗粒尺寸分布对水泥强度的影响进行数学分析.研究表明:熟料颗粒粒径在0～30 μm为正关联,>30 μm为负关联,其中10～20 μm颗粒对水泥强度的影响最大;粉煤灰颗粒粒径在0～40 μm为正关联,且其活性较高,>40 μm颗粒为负关联,其活性没有得到充分发挥.     

高钙灰-水泥颗粒群匹配与强度关系研究

本文将不同颗粒群分布的高钙灰、水泥按5:5比例混合,制成高钙灰水泥,测其3d、28d胶砂抗折、抗压强度。用激光粒度仪分别检测高钙灰、硅酸盐水泥的颗粒群分布。运用Rosin-Rammler公式对高钙灰、硅酸盐水泥及高钙灰水泥进行拟合。应用Origin软件,以宏观性能指标为z轴,水泥与高钙灰特征粒径之差为x轴,水泥与高钙灰复合胶凝粉体的特征粒径De 为y轴,进行三维区域图分析。给出强度发展趋势与水泥、高钙灰的相对位置以及复合胶凝体系总体细度的相互关系。     

粉煤灰组成与其胶砂活性的灰色关联分析

采用不同化学成分的粉煤灰试样,通过遴选试样及粉磨,使它们的细度及颗粒群分布基本一致,以50％的比例掺入纯硅酸盐水泥中,制成粉煤灰硅酸盐水泥。参照水泥标准测其各龄期的胶砂强度。采用灰色关联分析的方法,以粉煤灰水泥各龄期胶砂抗压强度为母序列,以相应的粉煤灰各组分含量为子序列,分析了粉煤灰各组分与其水泥胶砂宏观强度的关联度。本文进一步以XRD物相鉴定、酸溶解法等测试手段研究了粉煤灰矿物成分以及玻璃体含量与化学成分的关系,证实了灰色关联的分析结果。     

生物质灰对水泥硬化浆体抗压强度影响的试验研究

对比研究了生物质灰与普通粉煤灰在粒度分布、颗粒形态、化学组成、活性指数等方面的不同,并开展了不同掺量生物质灰对水泥硬化浆体抗压强度的影响研究.结果表明:生物质灰颗粒形状不规则、平均粒径及粒径分布范围较大,具有特有的细长纤维状颗粒,且其活性组分Al2O3不足普通粉煤灰的三分之一;生物质灰的火山灰活性小于普通粉煤灰;相同掺量下,生物质灰-水泥复合胶砂各龄期的抗压强度均小于普通粉煤灰-水泥复合胶砂,生物质灰掺量越大,复合胶砂的强度相比纯水泥组下降程度越大;与普通粉煤灰相比,掺加生物质灰的硬化水泥浆体微观结构更为疏松多孔,特别是其特有的细长纤维状颗粒的存在.     

改性高钙粉煤灰水泥的各项性能研究

以高钙粉煤灰为原料,机械粉磨高钙粉煤灰至比表面积388.14 m2/kg,配比为50%高钙粉煤灰、45%熟料、3%石膏、1%Ca(OH)2、1%J2,制备高钙粉煤灰水泥,并对比市售普通硅酸盐水泥,通过测量计算不同龄期条件下的强度损失率、长度变化率和干缩率等参数来表征水泥各项性能.结果表明,随着龄期的增长,硅酸盐水泥的抗折、抗压强度、抗冻性及抗硫酸盐侵蚀性强度损失率和干缩率分别为8.05 MPa、56.97 MPa、45.73%、36.2%、1.8× 10-4%,而高钙粉煤灰水泥分别为8.33 MPa、58.77 MPa、37.5%、26.7%、1.5×10-4%,均优于普通硅酸盐水泥,并随龄期增长越加明显.     

粉煤灰粒度分布及其活性的灰色关联分析

用激光粒度仪测定不同细度粉煤灰的粒度分布,以灰色关联方法分析了粉煤灰粒度分布与其活性之间的相关性.研究表明:粉煤灰粒度分布明显影响其活性;0～19.953 μm范围内的颗粒体积分数与粉煤灰活性指数的关联极性均为正,说明这些颗粒对粉煤灰的活性有积极贡献;其中以5.012～19.953 μm的关联度为最大,说明该粒径范围内...     

硅灰掺量对海工水泥混凝土耐久性能的影响

以粉煤灰、矿粉为混合材与硅酸盐水泥熟料、石膏复合,通过内掺硅灰制备海工水泥,研究硅灰掺量对海工水泥物理性能和混凝土耐久性能的影响。试验结果表明,掺入硅灰能明显增加海工水泥的标准稠度用水量,延长凝结时间,且与硅灰掺量呈正相关;当硅灰掺量≤4%时,水泥砂浆的抗压强度和抗折强度均随硅灰掺量的增加而增大,耐久性也逐渐提高;当硅灰掺量4%时,其强度和耐久性能的增加效果并不明显。颗粒分析结果表明,所制备海工水泥在0~30μm粒径范围内的比例高于普通硅酸盐水泥,颗粒分布更合理。XRD分析结果表明,适宜的硅灰掺量(4%)能充分发挥其火山灰效应和物理填充作用,提高水泥石的致密度。     

助磨剂对矿渣硅酸盐水泥性能影响的研究

实验采用有机化合物复配无机盐的方式,制成三种液体复合助磨剂,通过测定矿渣硅酸盐水泥细度、标准稠度、凝结时间、安定性和胶砂强度,研究不同助磨剂及助磨剂不同掺量对矿渣硅酸盐水泥物理性能的影响,并利用激光粒度仪和扫描电镜测试与分析了水泥的粒度分布和颗粒形貌.结果表明:三种助磨剂均能不同程度降低水泥筛余,提高水泥比表面积,提高幅度为2.9％～18.3％;掺入助磨剂后,水泥的颗粒形貌趋向于圆球形,水泥粒度分布发生变化,3～32 μm颗粒含量显著增加,中位粒径降低,其中B3水泥试样中位粒径为18.94 μm,降低了5.21μm;水泥凝结时间缩短,标准稠度变化不大,安定性符合国家标准;助磨剂能显著提高水泥各龄期胶砂强度.B3试样3d抗折强度为4.3 MPa,3d抗压强度为15.1 MPa,符合P·S 32.5R级标准要求.     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2007～2008年世界塑料工业进展

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.     

2005～2006年国外塑料工业进展

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。