首页 | 官方网站   微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
亚麻/聚丙烯复合材料的成型工艺和拉伸性能研究   总被引:2,自引:2,他引:0  
本文探讨了亚麻/聚丙烯纤维复合材料的制备工艺和拉伸性能.对亚麻纤维含量分别为30%、40%、50%、60%、70%的复合材料进行比较,分析增强纤维含量对复合材料拉伸性能的影响;对模压温度分别为150℃、160℃、170℃、180℃、190℃的复合材料进行比较,分析模压温度对复合材料拉伸性能的影响,最后确定模压温度及亚麻/聚丙烯纤维的混合比.  相似文献   

2.
为提高漂白全棉筒子纱的白度、强力、毛效等指标,在生产中探讨了水质、过氧化氢用量、漂液pH值、氧漂温度、氧漂时间对筒子纱性能的影响,得出了全棉筒子纱的最佳氧漂工艺。其中27%双氧水浓度12~13 g/L,pH值10.5~11.5之间,氧漂温度与时间控制98±2℃,55分钟。在此工艺下,全棉筒子纱的白度、强力、毛效获得最佳协同效果,可满足客户要求。  相似文献   

3.
以亚麻纤维为原料,聚丙烯为基体,制备纤维含量分别为0%、10%、20%、30%、40%的纤维增强复合材料,并对亚麻纤维进行碱处理和偶联剂处理,探讨了纤维含量以及表面处理对亚麻纤维增强复合材料的隔声性的影响。研究结果表明,当纤维含量超过10%时,复合材料的隔声性随着发声频率增加出现先增大后减小的趋势,同一发声频率,含量越低,隔声性能越差,当纤维含量超过30%后,电压峰值衰减率反而下降;表面处理后,复合材料的隔声性能有所提高,偶联剂处理后复合材料的隔声性能优于碱处理后的复合材料。  相似文献   

4.
亚麻粗纱染色的工艺研究与生产实践   总被引:10,自引:4,他引:10  
根据亚麻纤维的性质,讨论了前处理工艺粗纱染色工艺。采用硫酸或醋酸酸洗15分钟,中等碱度煮练50-60分钟,经过氧化氢氧漂或亚氯酸钠亚漂后,再用活性染料、还原染料或直接染料染色。详细描述了各类染料的染色工艺。  相似文献   

5.
电子电气设备等产生电磁辐射污染会严重影响到人体健康,并干扰设备的正常运行,解决电磁污染的关键是使用电磁屏蔽材料。采用模压工艺制备了具有电磁屏蔽功能的环氧树脂/碳纤维(CF)/亚麻纤维复合材料。借助矢量网络分析仪、热重分析仪、万能试验机、扫描电子显微镜(SEM)等研究CF粉对复合材料的电磁屏蔽性能(EMI SE)、热稳定性和力学性能的影响。结果表明,复合材料的弯曲强度随着CF粉含量的增加而增加,并在其质量分数为30%时达到最大值,为102.5 MPa,与未加CF的材料相比较,提高了31.1%,此后进一步增加CF粉含量,复合材料的弯曲强度开始下降。SEM证实,复合材料力学性能的提高来源于CF与环氧树脂界面性能的改善。CF粉的加入提高了环氧树脂/亚麻纤维复合材料的热稳定性,热分解温度从206℃提高到268℃。同时复合材料的体积电阻率随着CF粉含量的增加而下降,从0.65Ω·cm降至0.132Ω·cm。在8.4~12.4 GHz电磁波范围内,环氧树脂/CF/亚麻纤维复合材料的EMI SE达到20 dB以上,基本满足商业要求。  相似文献   

6.
探索美国生态实验室Microbe-lift复合菌剂处理高矿化度含油废水的可行性及处理性能。研究结果表明:Microbe-lift菌在pH值5.5~9.5和温度20~40℃的范围内能有效降低废水COD值;在pH值为7.5、温度30℃,接菌量15%时,初始COD值为688 mg·L~(-1)的废水经120 h处理后,COD去除率可达到63.15%。  相似文献   

7.
以钾长石和粉煤灰漂珠为主要原料,矾土为调质剂,在空气气氛下经900~1 150 ℃保温1 h制备得到轻质隔热材料,并研究了烧成温度与矾土含量对轻质隔热材料服役性能的影响规律及作用机理。结果表明,通过提升烧成温度或增加矾土含量,能够有效优化轻质隔热材料的常温物理性能。当烧成温度为1 100 ℃、调质剂矾土质量分数为20%时,试样具有最佳物理性能,其体积密度约为(0.97±0.01) g·cm-3,真气孔率约为(63.7±0.5)%,常温耐压强度达到(9.42±0.21) MPa,同时其300 ℃和600 ℃下的高温热导率分别约为0.147 W/(m·K)和0.229 W/(m·K),与一般轻质隔热材料相比同样具有优异服役性能,且制备成本较低。  相似文献   

8.
李璇  廖德祥  王莹  杨开亮  王博  张坤 《水处理技术》2020,46(1):94-98,102
考察了在不同基质含量、pH及温度条件下,磷酸盐对厌氧氨氧化(Anammox)反应器脱氮性能的影响。结果表明,在温度30℃、pH为7.8~8.2,高基质含量下,TP的抑制质量浓度为70 mg/L,而在低基质含量下TP的质量浓度达到30 mg/L就开始抑制脱氮性能;在低基质含量、pH为7.8、温度25℃条件下,反应器更容易受到磷酸盐的影响。本实验中,当反应器的脱氮性能受到磷酸盐抑制后,只要逐渐降低进水中磷酸盐含量和pH可恢复其脱氮性能,表明磷酸盐对Anammox菌活性的抑制是可逆的。  相似文献   

9.
一种新型的具有低分子量和窄分子量分布的高固含量丙烯酸树脂漆已研制问世,它被试用于汽车面漆。该面漆以二氧化钛为颜料,以六甲氧基甲基密胺为交联剂。它的固化周期在130℃时为30分钟,虽然其固含量高达70%以上(重),但在一定的环境温度条件下,也能保持理想的工作粘度。该面漆的所有性能,包括其机械性能、耐老化性能、耐蚀性能、耐二甲苯和耐水性能、及在亚利桑那州和佛罗里达州所做的耐久性能,经试验都高于或同于传统的热固性丙烯酸树脂漆性能。  相似文献   

10.
采用高掺量(80~95%)粉煤灰漂珠引入孔隙,添加部分膨润土为结合剂,少量PVA溶液为增塑剂,研究了不同配方以及烧成温度对轻质隔热材料各项性能的影响。通过XRD、SEM及导热性能测试等分析,结果表明:随着配方中粉煤灰漂珠含量的减少,膨润土含量的增加,坯体的体积密度、抗压强度以及导热性能都有逐渐增大的趋势;随着烧成温度的升高,坯体的体积密度、抗压强度以及导热性能也呈逐渐增大的趋势;在1200~1300℃烧成温度下的坯体性能为:体积密度0.433~0.619 g/cm~3,抗压强度5.35~15.8 MPa,并且在超轻体积密度为0.38 g/cm~3时,抗压强度仍然有3.2MPa(1150℃)。  相似文献   

11.
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   

12.
13.
14.
15.
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   

16.
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   

17.
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   

18.
Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

19.
20.
Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号