For graphene oxide (GO) composite hydrogels, a two-dimensional GO material is introduced into them, whose special structure is used to improve their properties. GO contains abundant oxygen-containing functional groups, which can improve the mechanical properties of hydrogels and support the application needs. Especially, the unique-conjugated structure of GO can endow or enhance the stimulation response of hydrogels. Therefore, GO composite hydrogels have a great potential in the field of wearable devices. We referred to the works published in recent years, and reviewed from these aspects: (a) structure of GO; (b) factors affecting the mechanical properties of the composite hydrogel, including hydrogen bond, ionic bond, coordination bond and physical crosslinking; (c) stimuli and signals; (d) challenges. Finally, we summarized the research progress of GO composite hydrogels in the field of wearable devices, and put forward some prospects.

This article analyzes the structural characteristics and working principles of heat treatment equipment while considering the possibility of “zero-carbon manufacturing.” It integrates the concepts of material flow, energy flow, and waste recycling, and, by following the life cycle theory, constructs a system boundary model for heat treatment equipment to track the direction of carbon emissions throughout various stages. It identifies the sources and forms of carbon emissions in the entire process of heat treatment equipment and proposes carbon emission estimation models for each stage, upon which a comprehensive data inventory for heat treatment equipment is established.