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以1,10-邻菲罗啉(1)为原料制备4,5-二氮芴-9-酮(2),并合成4,5-二氮杂芴(3)和9-亚甲基-4,5-二氮杂芴(5),再利用正丁基锂(或甲基锂)与上述两种二氮杂芴反应得到相应的锂盐,在-50℃下与旋光的环氧氯丙烷(ee98%)反应得到光学纯的含二氮杂芴基取代末端环氧化合物,它们的ee值均大于98%.将4,5-二氮芴-9-酮与乙基溴化镁(或苯基溴化镁)反应,得到相应的叔醇.叔醇在氢氧化钾和四丁基溴化铵存在下,与旋光的环氧氯丙烷反应,也得到光学纯的含二氮杂芴基取代末端环氧化合物,ee值均大于97%.将末端环氧化合物在不同条件下聚合,得到分子量分布很窄的含二氮杂芴基的聚醚.通过核磁共振、元素分析、凝胶渗透色谱等手段对产物进行了表征,对影响聚合的相关因素做了探讨. 相似文献
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Gelatin-based porous carbon beads have been fabricated from gelatin micro-spheres by means of solidification, carbonization and chemical activation with KOH. The physical properties of gelatin-based porous carbon beads were studied by a t-plot method based on N2 adsorption isotherms. The gelatin-based porous carbon beads activated at 800 ℃ exhibited the largest specific surface area and resulted in the highest capacitance. Carbon/carbon super-capacitors cells assembled with the electrode materials in 1.0 mol·L-1 NEt4BF4 / acetonitrile electrolyte have also been studied. The electrochemical properties of gelatin-based porous carbon beads electrode were studied by using constant-current discharge tests. The results indicate that the gelatin-based porous carbon beads electrode is with good cycling stability and specific capacitance of 119.8 F·g-1. 相似文献
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We report a fiber Bragg grating(FBG)-based sensor for the simultaneous measurement of a train bearing's vibration and temperature. A pre-stretched optical fiber with an FBG and a mass is designed for axial vibration sensing. Another multiplexed FBG is embedded in a selected copper-based alloy with a high thermal expansion to detect temperature. Experiments show that the sensor possesses a high resonant frequency of 970 Hz, an acceleration sensitivity of 27.28 pm/g, and a high temperature sensitivity of 35.165 pm/℃. A resonant excitation test is also carried out that demonstrates the robustness and reliability of the sensor. 相似文献
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MPIIID制备TiAlN涂层的高温抗氧化及摩擦性能 总被引:3,自引:1,他引:2
采用多源等离子体注入与沉积(MPIIID)装置制备了不同Al含量的TiAlN涂层,利用X射线能谱仪(EDX)、扫描电镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)、纳米探针和摩擦试验对涂层的组成以及高温抗氧化和摩擦性能进行分析。结果表明:Al元素的加入明显提高了涂层的高温抗氧化能力,生成的Al2O3能有效地抑制氧的扩散;当Al的质量百分数为6.18%时,涂层硬度最高,约为38GPa,涂层具有良好的摩擦磨损特性。 相似文献
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通过在物联网环境下对微车后桥的数字制造技术进行全面的分析和关键技术开发,包括对汽车后桥装配、制造的数字化技术研发、汽车后桥数字化检测技术的研发、汽车后桥车间物流信息管理系统的研发.实现物联网环境下的微车后桥的全数字制造. 相似文献
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网络安全是网络空间安全的一个重要研究领域,网络安全协议则是实现网络安全的核心技术.在2017年最新发布的TLS1.3协议是实现网络安全的一个关键传输层安全协议,因此其安全性受到了人们的广泛关注.为了验证TLS1.3协议的安全性,尤其是秘密性和认证性,尝试基于符号模型,首先基于Applied PI演算对TLS1.3协议进行形式化建模,进而使用非单射性建模认证性,然后将针对TLS1.3协议的Applied PI演算模型转换为安全协议分析工具ProVerif的输入,应用ProVerif对其进行形式化分析,实验结果表明TLS 1.3协议具有良好的认证性和机密性. 相似文献