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Polymer-based thermal conductive composites (PTCs) with good thermal and mechanical properties are highly appreciated in the thermal management of modern electronic devices. However, the heat transfer property of particle-filled PTCs is severely limited by the thermal resistance at both filler-matrix and filler-filler interfaces. Intensive efforts have been taken to enhance the filler-matrix interface, however, the effect of filler-filler thermal contact resistance on the heat transfer properties of PTCs is still not very clear. In this work, continuous thermal conductive networks with good filler-filler interface contact are formed in epoxy composites via the in-situ sintering of silver nanoparticles on the surface of boron nitride nanosheets (BNNS). In this composites, homogeneously dispersed and well exfoliated BN nanosheets are bridged to each other via the sintered AgNPs located at the BNNS and a 3D boron nitride nanosheets network is formed with solid Ag junctions lying in between. After thermal sintering process, the thermal conductivity of EP/BNNS@AgNPs composite with the 3D boron nitride nanosheets network increase from 0.95 W/m·K to 1.13 W/m·K at the filler loading of 20 wt%, which indicates that merged AgNPs are used as thermal transport junctions to reduce the thermal contact resistance within 3D BNNS networks. The present strategy provides an effective route for developing high-performance PTCs.

Serious bacterial infection induces the failure of artificial implants. Covalent bonding of antimicrobial peptides (AMPs) on implant surfaces can avoid the main shortcoming (blast releasing) by physisorption, but the low grafting yield, mobility, and stability of bonded AMPs limit their antibacterial efficiency. In this study, hydroxyapatite (HA) nanorods co-doped with Fe and Si were fabricated on Ti based on previous work, and the antimicrobial peptide HHC-36 was chemically bonded on the nanorods with and without polymer brushes as a spacer. The microstructures and physicochemical properties of coating surfaces were observed; Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and hFOB1.19 behaviours in the presence of in vitro antibacterial activity, and the immunization response in vivo on various surfaces were evaluated. The results show that the grafting of polymer brushes and HHC-36 did not substantially change the microstructure of the nanorods, but the brushes efficiently increased the load and stability of the HHC-36. The HA nanorods did not kill bacteria, but with the assistance of HHC-36, physical puncturing by nanorods worked efficiently in killing S. aureus. In contrast with Ti, in phosphate-buffered saline and suppressed biofilm formation in a nutrient-rich medium, HA nanorods with polymer-brush-grafted HHC-36 killed 99.5% of S. aureus and 99.9% of E. coli. This outstanding antibacterial activity was attributed to the synergistic effect of AMP-derived destruction and the physical puncturing by HA nanorods. Also, HA nanorods with polymer-brush-grafted HHC-36 showed cytocompatibility in vitro, and in vivo they inhibited bacterial infection and reduced the inflammatory response, indicating that polymer-brush-grafted HHC-36 on HA nanorods has great potential application in surface modification of Ti implants, especially in infected cases.

Municipal solid waste incineration (MSWI) fly ash, containing heavy metals and dioxins that can migrate and accumulate in biosphere, poses severe threats to human health and the environment. This review summarizes the sources and characteristics of heavy metals and persistent organic pollutants in MSWI fly ash, and comprehensively compares and discusses various treatment methods of MSWI fly ash, such as thermal treatment, pyrolysis process, hydrothermal treatment, solidification/stabilization (S/S) method and leaching process. Besides, the mechanism of dioxins degradation, and the principle of heavy metals solidification and recovery are analyzed in detail. Moreover, the pre-removal methods of chlorides are compared due to their adverse effect on the treatment processes of MSWI fly ash. However, to date, most of the disposal processes only have good effect on dioxins or heavy metals, except for pre-washing thermal treatments (sintering, melting and vitrification etc.) which need high energy consumption and complex equipment. Finally, low-temperature catalytic pyrolysis with electrolytic manganese residue (EMR) and S/S combined process of MSWI fly ash, and collaborative treatment of MSWI fly ash with melting furnace to degrade dioxins and enrich heavy metals are proposed. Those can provide some reasonable development directions for a completely harmless treatment of MSWI fly ash based on the comprehensive analysis of all hazardous components.

Ni/ZnO is used as a catalytic sorption material together with structural substrate for the S Zorb desulfurization process. At industrial scale, the use of Al2O3/SiO2 materials as such structural substrate results in long-term deactivation via the formation of Zn2SiO4 under hydrothermal conditions. This work aims for the investigation of the origin of such solid-state reaction by applying multiple characterization techniques, e.g. in-situ XRD, solid-state NMR and FT-IR. Two different common Al2O3/SiO2 materials, i.e. perlite and Al-montmorillonite, are studied comparatively in this work. As a result, Al-montmorillonite shows superior hydrothermal stability than perlite. It is observed that the density and reactivity of the Si-OH group is directly correlated to the formation rate of Zn2SiO4. Moreover, it has been further shown that the hydrogen-bonded Si-OH and bound molecular water are the major active species which lead to the formation of Zn2SiO4, as compared to the isolated silanol group. At last, both substrates are used for the preparation of the catalytic sorption materials in the S Zorb process. The desulfurization results show that the sorbent that has been prepared by using Al-MMT as structural substrate has maintained the sulfur-removal activity for much longer time than the one prepared from perlite.