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碳纤维表面化学涂覆NiO 总被引:1,自引:0,他引:1
采用均相沉淀法在碳纤维表面进行了NiO涂覆,研究了沉淀剂种类、脱水方式、沉淀剂浓度、沉淀剂添加速度和沉积反应时间对涂覆效果的影响. 采用SEM和XRD对涂层进行了表征,得到了制备NiO涂层较为合适的工艺条件为:以尿素为沉淀剂,采取缓慢升温的方式脱水,沉淀剂浓度0.20 mol/L,沉淀剂滴加速度2 mL/min,反应时间120 min. 在此条件下制备的NiO涂层厚度均匀,无脱落现象. 抗氧化性测试结果表明,涂覆NiO涂层后,碳纤维的抗氧化性有明显的提高. 相似文献
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镍基高温合金陶瓷涂层的制备及性能表征 总被引:1,自引:0,他引:1
以Cr2O3粉、玻璃料及黏土为原料制成料浆,通过喷涂将其涂覆在镍基高温合金GH44的表面,采用热化学反应法于1050°C保温10min,熔烧制备出高温陶瓷涂层。通过扫描电镜和X射线衍射分析了高温陶瓷涂层的表面和截面形貌以及相组成,对涂覆陶瓷涂层的镍基合金的抗热震性能、抗氧化性能以及高温疲劳性能进行了测试。结果表明,陶瓷涂层结构致密,与基体结合牢固,具有良好的抗热震性能。涂覆陶瓷涂层的镍基合金其高温抗氧化性相对于基体提高了6倍以上,其高温疲劳性能明显改善。 相似文献
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溶胶—凝胶法莫来石被覆SiC复合微粒子的制备 总被引:3,自引:1,他引:2
本文采用溶胶-凝胶法以组成为3Al2O3.2SiO2的混合溶胶分别于和压力条件下,对SiC微细粉进行包覆处理,该涂覆层在低于1000℃下经1h热处理可结晶成莫来石层,研究了涂覆溶胶浓度、涂覆压力对涂层厚度、结晶化温度等的影响,涂覆后的SiC微粉在中高温的表面抗氧化性明显提高。 相似文献
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本文采用溶胶-凝胶法以组成为3Al2O32SiO2的混合溶胶分别于常压和压力条件下,对SiC微细粉进行包覆处理,该涂覆层在低于1000℃下经1h热处理可结晶成莫来石层,研究了涂覆溶胶浓度、涂覆压力对涂层厚度、结晶化温度等的影响,涂覆后的SiC微粉在中高温的表面抗氧化性明显提高 相似文献
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李江平 《合成材料老化与应用》2019,48(5)
采用表面涂层法对武术器械用碳纤维进行了表面改性处理,对比分析了原始碳纤维、表面涂覆ZrO_2涂层和Y-ZrO_2涂层的碳纤维的表面形貌、物相组成和界面剪切强度,并分析了涂层层数对涂覆Y-ZrO_2涂层的碳纤维的表面形貌和界面剪切强度的影响。结果表明,ZrO_2涂层和Y-ZrO_2涂层可以在碳纤维表面均匀涂覆,ZrO_2粉主要物相为m-ZrO_2和t-ZrO_2,Y-ZrO_2粉的主要物相为t-ZrO_2;随着温度的升高,碳纤维、碳纤维表面ZrO_2涂层和Y-ZrO_2涂层都会发生不同程度的质量损失,但是Y-ZrO_2涂层的失重速率最小;在Y-ZrO_2涂层层数为4时,Y-ZrO_2涂层在碳纤维表面可以均匀完全涂覆且不会在碳纤维间产生Y-ZrO_2涂层剩余;随着Y-ZrO_2涂层层数的增加,界面剪切强度呈现先增加而后减小的特征,在Y-ZrO_2涂层层数为4时取得最大值。 相似文献
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通过丝网印刷法在SS410合金上涂覆YCo0.6Mn0.4O3抗氧化涂层材料,采用氧化增重法、SEM-EDX、四探针法分别对SS410合金及其涂覆抗氧化涂层后的高温氧化速率、微观形貌和面积比电阻进行了表征. 结果表明,通过丝网印刷法在合金表面涂覆连续致密的陶瓷涂层材料,YCo0.6Mn0.4O3涂层在循环氧化过程中与基底结合牢固,没有出现剥离脱落. 涂覆YCo0.6Mn0.4O3涂层后,在800℃下SS410合金的氧化速率降低1个数量级,在800℃氧化150 h合金的面积比电阻由未涂层的72 mW×cm2降到了16 mW×cm2,大幅度地提高了合金的高温抗氧化性能及电导性能. 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