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A simple europium complex,Eu(TTA)3 AA(TTA=4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione,AA=acrylic acid) was synthesized by a simple solution method.Then,two kinds of rubber matrix,nitrile-butadiene rubber(NBR) and silicone rubber(SiR) were used as the substrate for Eu(TTA)3 AA to prepare fluorescence composites.The neat Eu(TTA)3 AA complex showed the ability of self-polymerization when it was heated at 145 °C.It was found that the fluorescence intensity of the neat Eu(TTA)3 AA decreased over 70% when the polymerization time was over 25 min at 145 °C.The results also revealed that the polymerizated Eu(TTA)3 AA could be dispersed in nano-scale in two matrices and the luminescent intensities decreased 52% in NBR matrix,and 95% in SiR matrix compared with two relative compounds without crosslinking.To optimize the luminescence intensity of the composites,the Eu(TTA)3 AA polymerization kinetic process in matrix was investigated in detail by controlling the temperature,the crosslinking agent,etc.The results showed that the peroxide could accelerate Eu(TTA)3 AA self-polymerization in the rubber matrix,and therefore improved the dispersion,but not be helpful for the luminescence intensity enhancement.In addition,the relatively higher luminescence intensity in Eu(TTA)3 AA/NBR in comparison to that of Eu(TTA)3 AA/SiR might contribute to the interaction between nitrile group(–CN) in NBR and Eu-complexes,suggesting that the luminescence intensity of the composites also depended on the matrix characteristics. 相似文献
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在武器系统集成设计中,为了满足整体布局和高机动性的需要,对搜索雷达的运输及工作状态有严格的位置限制,机构的允许安装空间有限。传统的翻转机构形式难以实现,因此提出一种新型的适合于搜索雷达升降和倒伏的联动机构。该机构将搜索雷达安装于联动件上,联动件在升降平台的驱动以及水平滑道的限制下实现升降和倒伏的联动,从而实现搜索雷达的姿态转换。基于UG软件对该联动机构建立了数字模型,对雷达架设过程中天线转角、滑块速度以及关键旋转轴的受力情况进行求解,并与传统设计方案进行对比分析。分析结果表明,本文提出的联动机构结构紧凑,运动平稳空间减少约35%,需要的最大驱动力降低约43%,优化效果明显,满足使用要求。 相似文献
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水性环氧防腐涂料研究 总被引:3,自引:3,他引:0
目的研制具有优异防腐性能的水性环氧类防腐蚀涂料。方法采用水性环氧树脂乳液与水性环氧固化剂聚酰胺作为成膜树脂,异丙醇、丙二醇甲醚作为助成膜剂,湿法绢云母、重晶石粉、滑石粉作为填料,防锈颜料体系采用氧化铁红、三聚磷酸铝、磷酸锌,并在涂料体系中添加防闪锈剂、去离子水、分散剂、消泡剂、防沉剂,经过高速分散、研磨制成水性环氧防腐涂料。通过物理机械性能试验,耐酸、碱、盐溶液浸泡和耐中性盐雾试验,测试涂层的综合性能。结果涂层的附着力、柔韧性和耐冲击性能分别达到1级、1 mm和50 cm。涂层的耐酸性(5%H_2SO_4,168 h)、耐碱性(5%NaOH,168 h)、耐盐水性(3%NaCl,30 d)和耐盐雾性能(按GB/T 1771—2007,1000 h)良好,各试样完成后,涂层完好。结论成膜树脂采用环氧当量为500±50的水性环氧树脂乳液与聚酰胺类水性环氧固化剂,控制环氧基与活泼氢当量配比为1:1,颜料体积浓度为30%,并使用三聚磷酸铝、磷酸锌与氧化铁红复配作为防锈颜料,所制备的涂层有优良的物理机械性能和防腐性能。 相似文献
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