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61.
为保证无线传感网络的长期稳定运行,提出了一种具有仿生自修复功能的节点设计方法.该方法采用现场可编程模拟阵列(FPAA)实现传感模块内部各电路的信号链路,用信号处理模块监测传感模块内部各电路的工作状态.当传感模块发生异常时,信号处理模块判别其内部异常电路位置,并驱动FPAA启动冗余备份电路,完成了传感模块的信号链路的动态重构,达到了节点自修复的目的.首先介绍了仿生自修复节点的总体设计方案;然后,以应变无线传感网络节点为具体应用对象,设计实现了传感模块可动态重构自修复无线传感网络节点;最后,通过信号异常饱和状态的自修复试验验证了节点的自修复功能. 相似文献
62.
Guochen Wang Weiping Xu Yanxin Zhang Dong Chen Yuhong Ma Changtong Song Wantai Yang 《应用聚合物科学杂志》2024,141(13):e55172
Dynamic B O bonds are often applied to fabricate reversible-cross-linking and reprocessable polymer networks due to their high thermodynamic stability and kinetic tunability. However, it is still difficult to tailor boronic ester polymers, which have both excellent mechanical and self-healing properties in the absence of external stimuli. To address the above challenge, a range of room-temperature self-healable vitrimers are prepared by the reactions of various poly(vinyl hydroxyalkyl ether-alt-dialkyl maleate) copolymers and 1,4-phenyldiboronic acid. The dynamic cross-linking networks offer the as-prepared vitrimers superior mechanical properties and thermostability. Because of the presence of dynamic boronic ester bonds, the networks also demonstrated self-healing (the tensile strength recovered to 83% after 3 days at room temperature) and reprocessing capabilities (no significant change in tensile strength after thrice process recycles). Moreover, the vitrimers have potential as promising damping materials with wide temperature windows around room temperature. For example, the vitrimer of poly(ethylene glycol monovinyl ether-alt-dibutyl maleate) and 1,4-phenyldiboronic acid demonstrates its tanδmax 1.18, Tg = 6.2°C and effective damping temperature range is from −16.4 to 48.5°C. 相似文献
63.
Light-responsive cellulose nanocrystal@polydopamine (CNC@PDA) modified fluorinated polyacrylate was synthesized by Pickering emulsion polymerization with light-responsive block copolymer modified CNC@PDA as stabilizer. The epoxy groups in poly(acrylic acid-co-acrylamide)-b-poly(glycidyl methacrylate)-b-poly(hexafluorobutyl acrylate-co-coumarin) amphiphilic triblock copolymer reacted with the hydroxyl and amino groups on the surface of CNC@PDA to form the modified CNC@PDA. The successful preparation of modified CNC@PDA was confirmed by means of FT-IR, XRD, TG, UV–Vis, surface tension measurement, and X-ray photoelectron spectroscopy (XPS) techniques. The results showed that the modified CNC@PDA had light-responsive and amphiphilic properties, and could be used as stabilizer to form stable Pickering emulsion. And the influence of modified CNC@PDA dosage on emulsion polymerization and film performance was systematically studied. The latex particle size decreased initially with increasing modified CNC@PDA dosage, from 0.6 to 1.0 wt%, and then increased. The mechanical, self-healing, and water–oil repellent properties of film were enhanced initially with increasing modified CNC@PDA dosage, from 0.6 to 1.0 wt%, and then declined. Atomic force microscope confirmed that the latex film had a rough surface. Moreover, the latex film comprising 1.0 wt% modified CNC@PDA presented not only high tensile strength (4.92 MPa), large elongation at break (657.70%), and superior oil/water repellency but also excellent self-healing property. 相似文献
64.
顾欣 《电信工程技术与标准化》2003,(8):74-81
本文系统地阐述了IP over DWDM的分层模型、关键技术,并对IP over DWDM技术在城域网中的应用和发展前景进行了介绍。 相似文献
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