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Summary Anaerobic ammonium oxidation coupled with iron(III) reduction (Feammox) with dinitrogen, nitrite or nitrate as end‐products is the most recently discovered nitrogen cycling process. This reaction has been observed in tropical forest soils, paddy soils and intertidal wetlands. However, Feammox has not been measured in mangrove wetlands. In this study, sediment slurry incubation experiments were combined with isotope tracing and acetylene inhibition techniques. Feammox was detected in mangrove sediments and ‘bare flats’ (mud flats without mangrove), with potential rates of 0.48 (±0.03 SE) mg N kg−1 day−1 (accounting for 6.4% of the total nitrogen loss through N2) and 0.38 (±0.02 SE) mg N kg−1 day−1 (accounting for 6.7% of the total nitrogen loss through N2), respectively. Microbially reducible iron(III) was added, which significantly (P < 0.01) increased the Feammox rate in contrast to no addition of iron(III). It was estimated that a loss of 12.33 t N year−1 was associated with Feammox in mangrove sediments of the Jiulong River Estuary, accounting for 0.04% of the total external inorganic nitrogen transported into the estuary. Overall, these findings demonstrate that Feammox can act as a nitrogen loss mechanism in mangroves. Highlights Feammox was investigated by ammonium 15N labelled isotopic tracing technique. Feammox rates in mangrove were larger than those in mud flats without mangrove. The nitrogen loss contribution of Feammox in mangrove was less than in other ecosystems. Tidal fluctuations and the large TOC would accelerate the Feammox process.

At present, high-damping rubber materials, widely used in the field of engineering seismic isolation, generally have the problems such as narrow effective damping temperature range, low damping loss factor and strong temperature dependence, which lead to prominent dependence of temperature and load conditions of the isolation performance of high-damping rubber isolation bearings. Research and development of high-performance high-damping rubber materials with broad effective damping temperature range, high damping loss factor and weak temperature dependence are very urgent and necessary to ensure the safety of the seismic isolation of engineering structures. This paper mainly reviews the recent progress in the research and development of high-damping rubber materials using nitrile butadiene rubber (NBR), epoxidized natural rubber (ENR), ethylene propylene diene rubber (EPDM), butyl rubber (IIR), chlorinated butyl rubber (CIIR), and bromine butyl rubber (BIIR). This is followed by a review of vulcanization and filler reinforcement systems for the improvement of damping and mechanical properties of high-damping rubber materials. Finally, it further reviews the constitutive models describing the hyperelasticity and viscoelasticity of rubber materials. In view of this focus, four key issues are highlighted for the development of high-performance high-damping rubber materials used for high-damping rubber isolation bearings.

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