Make it stop:
'Living' ceramics utilize bacteria for gas sensing and carbon capture
Dec 2024, phys.org
The work involved first 3D printing stacked, ceramic, spiral structures that could stand on their own. The structures were printed with pits on their outer surfaces to give bacteria a place to live. The larger pits were used as a way to channel nutrients to the bacteria.To further ensure the bacteria could feed for an extended period of time, they set the structures in shallow pools of nutrient solutions. As the water in the solutions evaporated, the nutrients were pulled up to the pits containing the nutrients via capillary action. The bacteria were then allowed to multiply, filling the pores that had been designed for them. Testing showed they could survive without further nutrients for up to two weeks.The research team used different types of bacteria for different purposes—with photosynthetic cyanobacteria, for example, the structure could serve as a CO2 extraction device, pulling the gas from the air. They also tried Escherichia coli and found that they made the structure a formaldehyde detector.
via ETH Zurich: Alessandro Dutto et al, Living Porous Ceramics for Bacteria‐Regulated Gas Sensing and Carbon Capture, Advanced Materials (2024). DOI: 10.1002/adma.202412555
Self-adjusting shading system mimics pine cones for energy-autonomous weather response
Jan 2025, phys.org
"We are achieving a shading system that opens and closes autonomously in response to changes in the weather, without the need for operational energy or any mechatronic elements. The bio-material structure itself is the machine."It's based on pine cones. In high humidity, the cellulosic materials absorb moisture and expand, causing the printed elements to curl and open. Conversely, in low humidity, the cellulosic materials release moisture and contract, causing the printed elements to flatten and close.
via University of Stuttgart Institute for Computational Design and Construction: Tiffany Cheng et al, Weather-responsive adaptive shading through biobased and bioinspired hygromorphic 4D-printing, Nature Communications (2024). DOI: 10.1038/s41467-024-54808-8
Unoccupied housing in China's urban areas emitting massive amounts of carbon, study finds
Mar 2025, phys.org
Prior research has shown that by 2021, approximately 17% of homes built in cities in China were unoccupied. Some in the field have suggested that the number has only grown since then, to between 20 and 65 million unoccupied units. This new research found that approximately 17.4% of all new residential units built between 2001 and 2018 have never been occupied.The total the team came up with was 55.81 million tons of carbon emissions solely due to the unoccupied housing units, which they note represent approximately 6.9% of China's total residential emissions. (One source of emissions is the footprint of the materials, and the second comes from heating and cooling, because most of the units are apartment buildings with central heating and cooling.)
via Tsinghua University: Hefan Zheng et al, Unused housing in urban China and its carbon emission impact, Nature Communications (2025). DOI: 10.1038/s41467-025-57217-7
