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1.
依据阻抗匹配原理制备了一种3层雷达吸波涂层,并在吸波涂层表面喷涂一定厚度的可见光、红外伪装涂料,比较了喷涂伪装涂料前后涂层吸波性能的变化。实验结果表明,三层结构的设计对提高涂层的吸波性能具有重要的影响,将电介质材料与磁介质材料复合所制备的吸波涂层具有厚度薄、面密度低、吸波频带宽的特点。雷达吸波涂层与可见光、红外隐身涂层复合后,其吸波性能基本保持不变。  相似文献   

2.
在对聚氨酯涂料、泡沫和常用吸收剂进行介绍的基础上,总结了目前聚氨酯基雷达吸波材料的应用与研究进展,指出聚氨酯泡沫基吸波材料由于具有密度小、成型快、稳定性好等性能而有望成为未来吸波材料发展的重点。  相似文献   

3.
针对某型号产品批生产的需求,从型号批生产节奏对雷达吸波涂料涂装的要求和涂装生产条件的实际出发,研究确定了适应型号批生产要求需具备的施工工艺性能,在此基础上对两种型号的雷达吸波涂料进行了施工工艺性研究,并以工艺性研究的结果引导了涂料配方的调整,最终优选了适应型号批生产要求的改进后的W型雷达吸波涂料,保障了某型号产品批生产的顺利进行。  相似文献   

4.
依据阻抗匹配原理制备了一种薄型单层结构雷达波吸波涂料。试验结果表明,由电磁损耗型吸波剂、磁损耗吸波剂和导电高聚物吸波剂制备的1 mm厚度单层结构吸波涂层在8~18 GHz范围内雷达波反射率≤-8 dB,具有厚度薄、吸波频带宽、面密度低、吸波性能强的特点。  相似文献   

5.
综述了目前国内外宽频轻质吸波涂料的研究动态,详细介绍了具有发展前景的空心微珠吸波材料、碳纳米管吸波材料、导电高聚物吸波材料、纳米吸波材料和智能隐身材料等新型宽频轻质吸波涂料的最新研究状况,并对雷达隐身材料应用技术的未来做了展望。  相似文献   

6.
从雷达隐身材料吸波原理和吸波材料类型出发,分析了不同类型雷达波吸收材料的吸波机制,同时对可作为雷达波涂料填料的吸波材料进行分类阐述,到雷达隐身涂层的制备方式与对填料的选择,并展望了雷达吸波涂层的研究趋势。  相似文献   

7.
《电镀与涂饰》2007,26(11):55-58
北京航空材料研究所研制成功多种雷达吸波材料和隐形涂料北京航空材料研究所研制成功了多种雷达吸波材料和隐形涂料,目前正在进行JH-7A型歼击轰炸机隐形化  相似文献   

8.
正伊朗研究人员采用纳米粒子研制出一种隐身涂料并应用于飞机机身涂装。据该项目经理Karim Osouli Bostanabad表示,研究采用氧化磁铁纳米粒子和碳纤维材料等合成了一种雷达吸波涂料,产品的制备方法简单且性价比高,其涂层对雷达波的吸收率很高。据其介绍,氧化磁铁纳米粒子能在碳纤维基材上形成薄涂层,而且纳米结构比微米结构具有更好的吸波性能。  相似文献   

9.
论述了雷达吸波涂料的组成和性能,研究了其施工工艺,介绍了施工要点,并提出了施工难点的解决措施。  相似文献   

10.
概述了雷达红外兼容吸波涂层的工作原理,简述了涂层失效的定义、表现形式和分类方法;引入了失效分析模型,对其失效原因进行了分析;综述了涂层与基材间的结合机理,从基材表面状态和涂层应力两个角度,论述了其对吸波涂层与基材间结合力的影响,并针对性地提出了基材表面前处理和涂料树脂体系改性优化等提高附着力的方法。为吸波涂料配方的设计提供理论指导,指明了涂装前处理的必要性和重要性,为后续涂装质量和涂层性能的发挥奠定了基础。对雷达红外兼容吸波涂层技术和涂层失效检测及修复技术的发展前景进行了展望。  相似文献   

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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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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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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   

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.
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.
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   

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