共查询到20条相似文献,搜索用时 62 毫秒
1.
分别以煤焦油为原料在300℃空气氧化120min-480min和以石油渣油为原料在220℃空气氧化300min-720min,制备了一系列具有相近软化点的煤焦油沥青和石油沥青。通过NMR、元素分析、软化点、族组成和偏光光学进行原料与沥青的结构分析。在1.6MPa,480℃下将改质煤焦油沥青和石油沥青进行焦化,考察了焦收率和光学组织结构变化情况。结果表明空气氧化可提高煤焦油和石油渣油的软化点、不溶物含量和焦收率。石油沥青成焦后均生成各向异性广域学结构。而煤焦油沥青成焦后各向异性光学结构单元尺寸则随空气氧化时间增加而逐渐减小。 相似文献
2.
3.
4.
5.
以脱除QI的煤焦油软沥青(软化点59℃)为原料,在常压下300~380℃范围内通过空气氧化制备一定软化点范围的通用级沥青炭纤维用各向同性沥青。考察了空气氧化温度、时间、流量对煤焦油沥青性质和结构的影响。结果表明,空气氧化可有效提高煤焦油软化点,并获得各向同性沥青。采用核磁共振谱、红外光谱和元素分析考察了原料和氧化沥青的分子结构。在360℃空气氧化90~130 min条件下,得到的氧化沥青软化点在190~250℃之间,并表现出良好的可纺性,经熔纺得到10~20μm的沥青纤维。 相似文献
6.
7.
本研究用刮膜蒸发器对制备中间相沥青的原料(软化点为60℃的石油沥青)进行了分离,并分别以未分离的沥青及分离出的重质沥青为原料在不同的条件下调制成中间相沥青。探讨了原料分子量分布及缩聚过程中温度、N2流量、缩聚时间对中间相沥青族组成分布、软化点和可纺性等性质的影响。 相似文献
8.
《应用化工》2022,(10):2437-2441
以净化缩聚沥青(中间相碳微球生产中的母液沥青)为原料,通过空气氧化法制备高软化点包覆沥青。通过单因素法,考察了空气流量、反应温度、反应时间对包覆沥青的基本性质(工业分析指标和光学显微结构)的影响。结果表明,当反应温度为300℃,空气流量160 L/h,反应时间为6 h,可制备出软化点(SP)为215℃,甲苯不溶物(TI)为56.00%,喹啉不溶物(QI)为8.41%,结焦值(CV)为75.83%,收率为68.56%,且在偏光显微镜下为光学各向同性的高品质包覆沥青。并利用元素分析、傅里叶转换红外光谱(FTIR)结合分峰拟合技术、热重分析仪(TGA)对高软化点包覆沥青的热稳定性进行研究。 相似文献
9.
通过对煤焦油沥青和石油沥青作粘结剂的焙烧碳制品物理特性的研究,探讨了它们在碳制品制造中的适用性和相关性。本文说明了煤焦油沥青是最适宜的粘结剂。用与煤焦油沥青相同软化点的石油沥青作粘结剂制得的碳制品的质量差,但将石油沥青软化点从78℃提高到150℃或在低软化点沥青中加入10%碳黑,则提高了焙烧碳制品的密度、强度和电阻系数。在高软化点石油沥青中加入10%碳黑形成的碳制品,能进一步提高其密度和强度值。这些值可以同用煤焦油沥青得到的值相比。但是,电阻系数有所提高。高芳香性的石油沥青可以作为一种良好的粘结剂加以使用。 相似文献
10.
包覆沥青对提高锂离子电池负极材料的性能起到重要作用。以乙烯渣油沥青为原料,通过常压热缩聚法制备包覆沥青。考察了反应温度、反应时间对包覆沥青的基础指标(软化点、甲苯不溶物、喹啉不溶物和结焦值)和光学显微结构的影响。研究结果表明:以N2作为保护气体,当热缩聚反应温度为390℃,反应时间为4 h的条件下,制备出了软化点为200℃,甲苯不溶物为35.47%,喹啉不溶物为1.11%,结焦值为67%的各向同性沥青。通过FTIR和TGA分析可知,乙烯渣油沥青和高软化点各向同性沥青的芳香性指数(Iar)分别为0.526 6和0.5377,在700℃热解残余质量分别为20.22%和50.79%。表明乙烯渣油沥青通过热缩聚处理后得到的高软化点各向同性沥青具有较高的芳香性和良好的热稳定性,是一种优质的包覆沥青。 相似文献
11.
12.
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
13.
14.
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
15.
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
16.
17.
18.
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.
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
20.
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