According to the cargo list, most of the nurdles on board were made of polyethylene, but that tells chemists little about their composition and what additives might be present. The CEJ collaborated with IPEN to test for toxic organic compounds in the recovered nurdles. The team found ultraviolet sensitizers, bisphenol A, and polycyclic aromatic hydrocarbons (PAHs), which are carcinogenic.
by Katherine Bourzac | January 22, 2023
We are interested in the isotopic composition of this organic matter, and we know that different biological processes can fractionate isotopes in a specific way. But for each of these proposed isotopic biosignatures, you can find a chemical process that fractionates isotopes the same way. For example, enzymes in the photosynthetic process make organic matter that is lighter in isotopic composition than the carbon dioxide it was derived from.
by Carolyn Wilke, special to C&EN | January 22, 2023
Because Fagradalsfjalls’s magma rises from the crust-mantle boundary, its isotopic composition reveals more about mantle chemical variability than lava flows studied previously, Marshall says. So from March to September 2021, when the volcano was active, he and his colleagues collected samples about every other day, and again when it erupted briefly in August 2022.
by Louisa Dalton, special to C&EN | December 30, 2022
He says the investments are in keeping with a long-term plan to put $1.1 billion into eight sectors, including fine chemicals, high-performance coatings, engineering plastics composites, and polyimide. The goal is to establish a company that can make an annual operating profit of about $500 million and post an operating profit ratio of at least 10%.
by Katsumori Matsuoka, special to C&EN | December 16, 2022
Swierk realized that it would be impossible to design a standardized protocol to investigate the photochemistry of tattoo inks when their composition remained enigmatic. So his team started analyzing the ingredients in about 100 commercial inks. “A majority of things that we’ve looked at have had some level of discrepancy,” Swierk says.
by Ariana Remmel | December 02, 2022
The performance of turbine blades made from these nickel superalloys depends strongly on the alloy’s lattice structure, not just its composition. Initially, manufacturers made the blades from polycrystalline versions of the alloy, meaning the microscopic crystalline regions, or grains, of the superalloy were randomly oriented, and the material had many grain boundaries.
by Mitch Jacoby | November 27, 2022