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研究了纳米TiO2、普通TiO2、玻璃微珠填充PVC糊的流变性能、存放性能及凝胶化性能。探讨了加入不同填充剂、温度及存放时间对PVC糊黏度的影响。实验表明,加入纳米TiO2后,PVC糊在高剪切速率变为低剪切速率时黏度发生突增;存放10 d后黏度下降很少,仅下降0.25 Pa·s;在高温(85℃)条件下,随着存放时间的延长,黏度上升趋势很剧烈;并且随填充剂用量增多,PVC糊的黏度增大。 相似文献
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连铸长水口密封元件的开发 总被引:1,自引:0,他引:1
以粒度<0.1 mm的高铝熟料、<0.1 mm的黏土、<0.01 mm的石墨以及<0.1 mm的金属铝粉为原料,采用黏度约6 Pa·s的树脂A或黏度约10 Pa·s的树脂B为结合剂制备了连铸长水口密封元件,考察了结合剂种类对常温保型性、高温密封性和高温使用时间的影响,以及石墨加入量(w)为0、1%、2%、4%时对水口密封元件脱模性、抗侵蚀性和抗氧化性的影响,并进行了现场试验.结果表明:(1)树脂B结合的试样强度虽然较低.但是具有良好的常温保型性;当温度高于600℃时,使用树脂B结合的试样使用时间更长;另外,采用树脂B结合的试样具有优异的密封性能.(2)当石墨加入量<2%时,随着石墨加入量的增加,试样的粘结强度和侵蚀深度都显著降低;当石墨加入量>2%时,石墨加入量的增加对试样的粘结强度和侵蚀深度影响降低.低温氧化时,由于氧化层疏松,石墨和树脂的氧化占主导地位,当加热温度>800℃时,生成致密的保护层而防止试样的进一步氧化,试样具有良好的抗氧化性.(3)现场试验结果表明,本研究开发的新型连铸长水口密封元件能够显著降低钢中的氮含量,具有优异的使用性能. 相似文献
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本文运用差示扫描量热分析(DSC)、X射线衍射(XRD)和场发射扫描电镜(FESEM)研究了TiO2含量对CaO-MgO-Al2O3-SiO2系微晶玻璃析晶过程和析晶动力学的影响.结果表明:随着TiO2含量的增加,玻璃转变温Ts和析晶峰温度Tp逐渐降低.当不加TiO2或者添加5wt%的TiO2时,玻璃发生表面析晶,析出的晶相为斜长石.当添加10wt%的TiO2时,玻璃样品在800℃热处理后发生剧烈分相,910℃晶化后出现整体析晶,晶相为普通辉石.随着TiO2含量的增加,析晶动力学常数k值增大.当添加10wt%的TiO2时,k值达到最大,为0.545,此时玻璃最容易析晶,相应的析晶活化能E和析晶指数n分别为643.329 kJ/mol和3.25. 相似文献
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用乙烯焦油与渣油按一定的比例混合,可以调和制备180#船用燃料油,考察了温度、调和质量配比、表面活性剂对调和油品黏度的影响。实验结果表明,在50℃的反应条件下,当m(渣油)/m(乙烯焦油)为1∶1.25和1∶1.50时,调和油的黏度符合180#船用燃料油的黏度标准。研究还发现,调和油中加入阴离子与非离子表面活性剂做的复配时能显著降低油品的黏度,当添加量为3‰时,效果最佳。 相似文献
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《煤炭转化》2015,(3)
利用陕北地区的兰炭末制备水炭浆,研究了兰炭末的粒度配比、制浆搅拌作用及温度对水炭浆表观黏度、流动性和稳定性的影响.兰炭末用实验室球磨机研磨好并筛合成830目(D1),200目~320目(D2),100目~200目(D3)和60目~100目(D4)四种粒径范围.结果表明,当兰炭末的粒度配比m(D1)∶m(D2)∶m(D3)∶m(D4)为5∶2∶2∶1,搅拌速率为1 500r/min,搅拌时间为15min,环境温度为30℃~40℃时,制备出的水炭浆质量分数可达到60%,表观黏度360mPa·s,浆体可以保持一个月内稳定并且流动性良好.随着细粒度兰炭颗粒加入量的增加,水炭浆表观黏度增大,流动性变差,稳定性增强.搅拌速率过高和搅拌时间过长会导致浆体老化,流动性变差.当温度逐渐升高时,水炭浆的表观黏度呈现出先降低后增加的趋势. 相似文献
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使用溶胶凝胶法制备了二氧化硅/二氧化钛/玻璃纤维体系复合催化膜(SiO2/TiO2/GF),研究了影响成膜的主要因素(PEG添加量、焙烧温度、溶胶特性等)的条件下SiO2/TiO2/GF的特性.采用气相甲醛对SiO2/TiO2/GF体系催化膜的光催化效率进行了评估. 研究表明在n(钛酸四丁酯):n(水)=1:1的时候, 聚乙二醇(PEG)添加为10 g/L, 当煅烧温度在500 ℃时候, SiO2/TiO2/GF膜光催化效率最高. 在停留时间为21 s、 12 s、 9 s时, 反应动力学常数分别为0.041 0、 0.049 8和0.049 8 mol/m3·min. 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