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For chemical recycling of plastic wastes to be viable, chemical products generated in recycling need to find markets. A network model of the U.S. chemical manufacturing industry was used to assess at what cost points, and the extent to which, chemical products from thermal pyrolysis of polyethylene might find markets in the current U.S. chemical manufacturing industry. Network modeling determined the cost points at which the simulated industry network utilized the thermal pyrolysis products and which processes were displaced by the supply of recycled materials. The characteristic feature of the simulations is the large number of processes in the chemical manufacturing network that are impacted by the availability of a relatively small number of products from polyethylene recycling. In the case of polyethylene recycling, the capital cost requirements for expanding capacity to effectively utilize the recycled materials is greater than the capital required for the pyrolysis process. This suggests that identifying scenarios where recycled materials can be utilized in processes that have excess capacity will be a critical consideration in techno-economic analyses of recycling plastics. 

Abstract Methane emission reductions are crucial for addressing climate change. It offers short-term benefits as it holds high short-term reductions in radiative forcing. Efforts towards the reduction of methane emissions are already underway. In this study, we compared and analyzed the mitigation benefits of cutting large amounts of methane emissions from the oil and gas sector on short-time scales with reducing an equivalent amount of carbon dioxide using carbon capture and storage (CCS). Characteristics of CCS are that it would require substantial infrastructure development and that it incorporates deployment delays. Results illustrate that prioritizing quickly deployable methane emission reduction alternatives that necessitate minimal construction is an efficient approach to achieve near-term climate change relief. Graphical abstract 

Foot drop is the inability to dorsiflex the ankle (raise the toes) due to neuromuscular impairment, and this common condition can cause trips and falls. Current treatments for chronic foot drop provide dorsiflexion support, but they either impede ankle push off or are not suitable for all patients. Powered ankle-foot orthosis (AFO) can counteract foot drop without these drawbacks, but they are heavy and bulky and have short battery life. To counteract foot drop without the drawbacks of current treatments or powered AFO, we designed and built an AFO powered by dielectric elastomer actuators (DEAs), a type of artificial muscle technology. This paper presents our design and the results of benchtop testing. We found that the DEA AFO can provide 49 % of the dorsiflexion support necessary to raise the foot. Further, charging the DEAs reduced the effort that would be required for plantarflexion compared to that with passive DEA behavior, and this operation could be powered for 7000 steps or more in actual operation. DEAs are a promising approach for building an AFO that counteracts foot drop without impeding plantarflexion, and they may prove useful for other powered prosthesis and orthosis designs.