Abstract Marine carbonate production and dissolution are important components of the global carbon cycle and the marine alkalinity budget. Global carbonate production by marine fish (ichthyocarbonate) has been estimated to be as high as 9.03 Pg CaCO3 yr−1; however, the fate of ichthyocarbonate is poorly understood. High magnesium concentrations in ichthyocarbonate would traditionally suggest rapid dissolution under current marine conditions, but a correlation between dissolution rate and mol%MgCO3has not been observed. Here, we aim to determine the role of organic coatings on dissolution rates of ichthyocarbonate in marine environments. We applied a combination of petrographic, geochemical, and microCT approaches to assess the quantity and distribution of organic matter in ichthyocarbonate produced by two species of marine fish, the Gulf toadfish (Opsanus beta) and the Olive flounder (Paralichthys olivaceus). We show that organic matter, including external coatings and embedded organic material, is volumetrically significant, ranging from 8.5% to 32.3% of ichthyocarbonate by volume. Bleach oxidation of external organic matter coatings increased the dissolution rate of ichthyocarbonate by more than an order of magnitude, suggesting these coatings serve to reduce reactive surface area of the mineral fraction in ichthyocarbonate. Assuming that organic coatings do not influence sinking rates, external coatings extend the depth of ichthyocarbonate persistence in the water column by ∼12–15×. Therefore, organic coatings are an important determinant of the role of ichthyocarbonate in the marine carbon cycle.
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Molecules to Masterpieces: Bridging Materials Science and the Arts
Abstract Art and materials innovation have always been intertwined, dating back to the earliest human creations. In modern times, however, the increasing specialization of materials science often restricts artists' access to cutting‐edge materials. Here, the materials science aspects of an art‐science collaboration between artist Kimsooja and the Wiesner Lab at Cornell University, are detailed. The project involves the development of a custom‐made iridescent block copolymer coating by means of self‐assembly, originally applied to transparent window panels of a façade for the ≈14 m tall art installation:A Needle Woman: Galaxy Is a Memory, Earth is a Souvenirby artist Kimsooja. After several exhibitions in the US and Europe, the installation is now part of the permanent museum collection at Yorkshire Sculpture Park in Wakefield, UK. Full characterization of the solution blade‐cast coatings show shear aligned, standing up lamellar morphologies that behave as volume‐phase gratings with periodicities between 300 and 400 nm. Coatings are also applied to foldable (origami) paper and converted into iridescent porous ceramic materials. It is hoped this work inspires and informs communities across materials science, the arts, and architecture.
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- Award ID(s):
- 2307013
- PAR ID:
- 10608909
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 37
- Issue:
- 11
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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