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Antimicrobial cotton fabrics received much attention for the demand of health and hygiene fields. In this work, an antimicrobial copolymer was prepared via a reaction between polyhexamethylene guanidine hydrochloride and polypropylene glycol diglycidyl ether. The copolymer has amphiphilic characteristic and excellent antimicrobial properties. When the copolymer was adhered onto cotton fabrics through physical adsorption and chemical bonding using dipping-drying method, the resultant cotton fabrics had excellent and durable antimicrobial properties. The antimicrobial rates against Escherichia coli and Staphylococcus aureus were higher than 99.99% when the adsorption amount of the copolymer was above 35.5 mg/g. The antimicrobial cotton fabrics remained the excellent antimicrobial properties even after laundered with detergent solution.

Nonbiodegradable features and the lack of antimicrobial activity for conventional synthetic polymer-based packaging materials remain as extensive concerns for environmental issues and food safety. In this work, an antimicrobial copolymer PHGH–PPGDE was synthesized via a reaction between polyhexamethylene guanidine hydrochloride (PHGH) and poly(propylene glycol)diglycidyl ether (PPGDE). The obtained PHGH–PPGDE was amphiphilic, antimicrobial and reactive due to the terminal reactive group. The TEM images indicated that PHGH–PPGDE formed aggregated particles dispersed in water. The antimicrobial paper was conveniently prepared by dip-coating a paper matrix in the PHGH–PPGDE aqueous dispersion, or mixing the dispersion with pulp. The resultant paper showed excellent antimicrobial activities against Escherichia coli and improved durability for the nonleaching effect.

The Qiantang River tunnel, which was planned in 2006 and completed in 2010, is the first slurry shield tunnelling in Hangzhou soft ground, and also the first tunnel under Qiantang River. In construction of this tunnel, in-situ instrumentation was installed to monitor the deformations and displacements of shield tunnel lings. This paper analyses the monitoring results in detail. Studies show that: (1) At the early stage after the shield tunnel lining installed, both of its deformation and movement are very small, but they are cumulative with time. So their impacts on ground surface settlements cannot be neglected. (2) After the tunnel lining installed, its horizontal diameter increases in the early time, and then it decreases gradually till it comes to a certain value. (3) Early after the tunnel lining being installed, due to buoyant force of synchronized grouting fluid, underground water and slurry fluid, the lining will float a little. And then the consolidation of the subgrade leads to lasting settlement of the tunnel lining. (4) Compared with ground surface settlements, those of the crown of shield tunnel are much smaller. The movements of the crown of the tunnel and ground surface have positive correlation, and the settlement of the crown will increase the ground surface settlement.

The Qiantang River originates in the borders of Anhui and Jiangxi provinces and passes through Hangzhou, the capital of Zhejiang province, before flowing into the East China Sea through Hangzhou Bay. It is known for the world's largest tidal bore, which is up to 9 meters high, and travels at up to 40 km per hour and has since ancient times been considered a spectacular sight. The Qiantang River tunnel, which was planned in 1996 and completed in 2010, is the first slurry shield tunnelling in Hangzhou soft ground, and also the first tunnel under Qiantang River. Whether the long-term impact of the surging tide will influence the normal service and structural safety of the under-river tunnel is concerned. In order to monitor the condition of the tunnel and study the impact of the tide on it, a structural health monitoring system was planed and applied in construction of the tunnel. Items of monitoring include the earth pressure acting on the shield tunnel lining, stain in the reinforcing steel bars of the segments, convergence of cross-section and long-term settlement in the longitudinal direction. Both traditional monitoring methods, such as the vibrating wire strain gauges, and the advanced fibre optic technology, such as distributed optical fibre strain sensing, were applied in this monitoring system. This paper describes the application of the structural health monitoring system in detail, including arrangement of monitoring sections, the installation of the instruments, and anticipated research achievements.