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Bacterial colonization and biofilm formation on the surface of materials can lead to serious bacterial infections and are highly detrimental to our health. Here, we prepared a water-insoluble HPL-DOSS complex by compounding hyperbranched polylysine (HPL) with docusate sodium salt (DOSS) and coated HPL-DOSS onto the surfaces of the commercial polypropylene (PP) and thermoplastic polyurethane (TPU) plastics to afford antibacterial PP-HD and TPU-HD plastics. PP-HD and TPU-HD showed excellent antibacterial activities against both Escherichia coli and MRSA. In addition, the bacterial residues on the PP-HD and TPU-HD surfaces were significantly reduced compared with the pristine PP and TPU surfaces, indicating that the HPL-DOSS surface coating had good anti-adhesive property against bacteria and helped to reduce the formation of biofilms. Meanwhile, both PP-HD and TPU-HD exhibited excellent biocompatibility, indicating that the HPL-DOSS complex could be used as a safe antimicrobial coating material to reduce bacterial infections on plastic surfaces. [ABSTRACT FROM AUTHOR]

This study develop an adaptive stationary target imaging technique based on the empirical mode decomposition (EMD) method for the time-division multiple-input multiple-output through-wall radar. By exploiting the discrimination between the respiratory rate and the environmental clutters' frequency, the weak echoes of the stationary target are enhanced via EMD processing adaptively. Based on the simulations as well as the experimental data, the authors verify that the stationary target can be positioned accurately via their proposed method. [ABSTRACT FROM AUTHOR]

Hydrolyzed polyacrylamide (HPAM) is widely used to increase the sweep efficiency of water phase in oil reservoirs. It is very important to select proper polymer for the reservoirs. In this study, a series of ultra-high molecular weight HPAMs were synthesized and characterized by FT-IR analysis. Their physical properties were tested under reservoir condition. BP neural network (BPNN) was employed to forecast the viscosity of high molecular weight HPAM in produced water. The input indices including molecular weight, solid content, degree of hydrolysis, water-insoluble residue, polymer concentration, temperature of reservoir and salinity of produced water. The results show that all physical properties fulfill the requirements of Q/SY DQ1059-2005. This BPNN can predict the viscosity of ultra-high molecular weight HPAM accurately. It is proposed that this BPNN can be used to screen proper polymers for enhance oil recovery. [ABSTRACT FROM AUTHOR]