Engineering all-aromatic polyamide surface from hydrophilic to superhydrophobic and the accelerated strategy

Being a new kind of nanomaterials, aromatic polyamide nanofibers (ANF) have been much highlighted in recent studies. We here demonstrate an isopropyl alcohol (IPA) accelerated chemical cleavage on poly (p-phenylene terephthalamide) chopped fibers, which provides an efficient preparation method of ANF. The comprehensive study on the processes accelerated by different alcohols revealed that the preparation time of ANF in the mixed medium of dimethyl sulfoxide (DMSO)-alcohol (20:1 in volume) was shorten to 45 min and 75 min for methanol (ethanol) and isopropanol, respectively. However, the nanofibers prepared in DMSO-IPA exhibited the minimum in axial and radial dimensions, providing the finest and most uniform diameter of 16 nm. The corresponding ANF films through vacuum assisted filtration also showed the highest tensile strength of 150 MPa, in comparison with those of the ANF films prepared using other alcohols, which were about 110 MPa. Furthermore, ANF/silicon hybrid films were prepared by the ionic ring-opening reaction followed by the alkoxysilane condensation and nanoparticle fabrication. By changing the organo functional groups in the alkoxysilane, the surface of the films were adjustable in a wide contact angle range from 56° (hydrophilic) to 150° (superhydrophobic), suggesting the amendable interfacial properties potential applicable to composite fabrication with most of the resin matrix.     

微小电偶腐蚀电流的准确测定

为了更多地获得电偶腐蚀的信息并揭示其本质规律，提出了电偶腐蚀试验实时监测模型。通过选用不同设备对试样的电偶腐蚀微小电流的测量，结果发现：选用现成设备测量试样的电偶腐蚀微小电流时，测量电流波动非常大，噪声明显超过实际信号输入——电偶腐蚀电流。经自行开发研制的MCD01电偶腐蚀计可以准确的测量腐蚀电流，特别是微小电偶腐蚀电流。     

Partial standard quantum process tomography

With the general theory of standard quantum process tomography, we shall develop a scheme to decide an arbitrary matrix element of χ, which is in the Choi matrix representation, in a scalable way. Our observation is that: To decide the diagonal matrix element, one just needs a single measurement; To decide an arbitrary off-diagonal matrix element, we should carry out sixteen measurements. This result is independent of the actual dimension of the system. Compared with the known methods of partial QPT, our scheme does not require any additional resources. It can be applied for the case where a clean ancilla system is not available.     

浅析《计算机网络》课程实验环境架构

本文针对当前贫穷地区高职高专计算机网络实验教学的特点,结合学校和本地实际情况,从实验课程教学内容及形式方法等方面探讨了计算机网络实验环境架构的有关问题.对计算机网络实验的环境构架存在的不足,给出了解决方案.     

Word2000文档恢复技术

通过对Word2000文档文件删除后的磁盘结构及文档文件结构的分析研究．给出恢夏Word2000文档文件的技术过程。     

一种基于小波变换的脉搏波速度测量方法

动脉脉搏波速度变化是动脉血管病变的指示剂,因此脉搏波速度的检测对血管疾病的预防和治疗有很大的帮助作用.脉搏波中夹杂的各种噪声干扰会影响测量结果精度.利用小波变换可以去除脉搏波中的各种干扰,实现波形的平滑重构,为提高测量精度打下基础.脉搏波波速的测量精度在很大程度上取决于波速参考点的提取,首次采用二次差分峰值点作为波速参考点,提高了测量精度.临床实验证明,新方法能够有效地分析出脉搏波速度,有助于动脉血管弹性程度的辅助诊断.     

基于图像检测的发动机缸体探伤系统设计及应用

为了实现某型号航空发动机缸体的自动化检测,设计了一套全自动荧光磁粉探伤系统。介绍了系统的结构和实现方式、重点介绍了图像采集和图像处理部分,系统采用Laplacian算子对原始图像进行锐化处理,然后采用Prewitt算子进行边缘提取,最后采用面积和周长两个物理量作为判断产品合格与否的特征值;实际测量显示,系统的测量精度可达0.01 mm,满足发动机缸体检测的要求。     

一个基于Web日志的用户访问数据分析系统

通过结合网站设计初期的网站结构和典型用例的预先定义,构建一个基于Web日志数据的用户访问数据分析系统。该系统（AS-UAB,Analysis System of User Access Behaviors）通过对网站结构和典型用例的预先植入,利用该领域最新的研究方法和结论,为网站相关人员提供可视化的用户访问信息统计及趋势预测,网站结构设计及交互设计上存在的问题及改进建议等通用功能和个性化定制功能。     

PCI接口高速数据采集与处理卡的设计

利用可编程逻辑器件搭建了一个可编程的数据采集平台.     

Blockchain Security Technology Based on the Asynchronous Transmission Mode of IoT Technology in Smart Cities

Wireless Personal Communications - With the rapid development of information technology, issues such as network security and privacy protection have attracted more and more attention. The...