A new bioslurry-induced restoration method via biomineralization for fragmented ceramic cultural relics

This study presents a new restoration method for fragmented ceramic cultural relics using bioslurry-induced biocementation via a microbially induced calcium carbonate precipitation (MICP) process. Bioslurry is highly urease active calcium carbonate crystals, which serve as filling and cementitious material with newly induced calcite precipitation when supplying cementation solution (urea and calcium source). With the pre-filling of bioslurry and newly induced calcite crystals, the fragmented ceramic can be connected and the gap along the fracture surface can be sealed. Due to the high urease active bacteria cells embedded in bioslurry, the ceramic restoration can be completed in 24 h with the optimal concentration of cementation solution of 1.6 M. Taking the advantage of bonding effect gained from newly induced calcite precipitation, the tensile strength was improved up to 0.92 MPa through a customized tensile strength test. This is satisfactory to ensure the stability and integrity of fragmented ceramic after bioslurry-induced restoration. A demonstrative restoration has been completed on fragmented ceramics from Ming Dynasty. With the good bonding strength and high stability of bioslurry-induced calcite precipitation, the proposed bioslurry-induced restoration method contributes valuable insights to the conservation of ceramic cultural relics. Other prospective applications include the restoration of masonry relics and bone relics.

Soil bioengineering using vegetation under climate change

The combined effects of climate change and intensified engineering activities have increased soil-related hazards globally,such as slope failures and dust storms(Cui et al.,2021).Shallow landslides and surface erosion frequently occur,particularly in response to heavy rainfall(Qin et al.,2022).These hazards result in the loss of human life and entail significant economic losses and environmental risks.Traditional engineering practices often use environmentally unfriendly materials,which have ecologically caused detrimental effects on geotechnical infrastructures.In recent years,people have been looking for more“green”solutions worldwide.Soil bioengineering using vegetation is a promising sustainable alternative and highly cost-effective strategy for strengthening topsoil so as to mitigate soil erosion and shallow landslides(Ng,2017).To address the issues encompassing social,environmental,ecological,and economic considerations,“green”engineering measures are suggested to promote sustainability by involving the vegetation approach(Rowe&Jefferis,2022).

Endeavours to achieve sustainable marine infrastructures:A new“window”for the application of biomineralization in marine engineering

1.Microbially induced corrosion on marine concrete The acceleration of urbanization has seen a change in marine engineering.Coastal cities increasingly expedite the development and utilization of oceanic resources for social-economic development.Concrete materials are widely used in the construction of offshore and marine engineering practices.

Microbial mineralization:A promising approach for stone cultural relics restoration

Stone Cultural relics are important carriers of human history,containing broad artistic,scientific,educational,and cultural connotations.They are often regarded as symbolic icons of various places.In the World Heritage List of the United Nations Educational,Scientific and Cultural Organization(UNESCO)(UNESCO,n.d.),many stone cultural relics have been included,e.g.,the Pyramid Fields from Giza to Dahshur in Egypt,the Acropolis,Athens in Greece,the Roman Colosseum in Italy,the Machu Picchu in Peru,and the Mogao Caves and Dazu Rock Carvings in China,etc.