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In order to safely operate the electric transmission lines, to monitoring the crossed span distance of the overhead lines is one of the key measures. Since the current measurement methods of crossed span distance of overhead line has high cost, low accuracy, and traditional measurement methods has low efficiency, the monitoring model of overhead line in three-dimensional space is constructed, and based on oblique parabola equation. The algorithm for detecting the crossed span distance based on three-dimensional inclination under the windless and windy conditions is studied, which are applied to the on-line monitoring system. Through actual measurement, the accuracy and practicability of the three-dimensional model and algorithm are verified which provides reliable algorithm support for traverse crossing distance measurement and on-line monitoring system, and improves work efficiency.

The development of advanced functional materials, capable of providing effective antimicrobial activity, has a big demand from the contemporary society. Advanced functional antimicrobial amorphous silica composites (ASC) are prepared by using sol–gel process and modified by Zn ions and rare-earth element Lu. The preparation conditions are optimized by single-factor analysis, and as-prepared functional hybrids are characterized by scanning electron microscopy (SEM), X-ray diffraction analysis, X-ray photoelectron spectroscopy (XPS), atomic adsorption spectrometry and inductively coupled plasma analyses. The presence of homogeneously mixed Zn and Lu, in the form of ZnO and Lu2O3, and dense micropores is confirmed by SEM and XPS. The amorphous structure and large surface area are beneficial for better antimicrobial performance. The as-prepared Zn–Lu ASC exhibited excellent antimicrobial properties against Escherichia coli and Staphylococcus aureus. We demonstrate that the addition of rare-earth element, Lu, has rendered synergistic effect on antimicrobial properties by increasing the release of Zn ions and generating excess reactive oxygen species. The present study provides a mechanistic insight and novel approach to fabricate functional antimicrobial materials for a wide range of applications.

Masses of chlorine salts in the oceans engender a badly electrochemical erosion on the concrete since cross- sea bridge and harbor construction has been intensified in recent years, which has aroused a wide concern. This paper aims to study the corrosion mechanism of seawater chloride ion on the concrete with upper and lower two layers of intertidal zones set up according to different positions. A test is designed to make a comparative analysis on the resistance of marine biofilm to chloride permeability in two cases that the biofilm is active and inactive. The results show that chloride ion takes place electrochemical reaction and plays dual roles of anodic depolarization and conductivity. For its permeability to chloride ions, active biofilm shows stronger, which may be correlated to the halophilic bacteria contained in biofilm and the surface bonding effect of concrete. In relation to the upper intertidal zone, the resistance to chloride penetration in the lower layer of concrete is superior, which reveals that the lower biofilm has a better adhesion effect on the surface and plays a certain role in preventing the erosion of harmful substances.