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That book is poison: Even more Victorian covers found to contain toxic dyes

Composite image showing color variation of emerald green bookcloth on book spines, likely a result of air pollution

Enlarge / Composite image showing color variation of emerald green bookcloth on book spines, likely a result of air pollution (credit: Winterthur Library, Printed Book and Periodical Collection)

In April, the National Library of France removed four 19th century books, all published in Great Britain, from its shelves because the covers were likely laced with arsenic. The books have been placed in quarantine for further analysis to determine exactly how much arsenic is present. It's part of an ongoing global effort to test cloth-bound books from the 19th and early 20th centuries because of the common practice of using toxic dyes during that period.

Chemists from Lipscomb University in Nashville, Tennessee, have also been studying Victorian books from that university's library collection in order to identify and quantify levels of poisonous substances in the covers. They reported their initial findings this week at a meeting of the American Chemical Society in Denver. Using a combination of spectroscopic techniques, they found that several books had lead concentrations more than twice the limit imposed by the US Centers for Disease Control (CDC).

The Lipscomb effort was inspired by the University of Delaware's Poison Book Project, established in 2019 as an interdisciplinary crowdsourced collaboration between university scientists and the Winterthur Museum, Garden, and Library. The initial objective was to analyze all the Victorian-era books in the Winterthur circulating and rare books collection for the presence of an arsenic compound called cooper acetoarsenite, an emerald green pigment that was very popular at the time to dye wallpaper, clothing, and cloth book covers. Book covers dyed with chrome yellow—favored by Vincent van Gogh—aka lead chromate, were also examined, and the project's scope has since expanded worldwide.

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Electronic Noise in vdW Layered AFMS (UCLA)

A technical paper titled “Electronic Noise Spectroscopy of Quasi-2D van der Waals Antiferromagnetic Semiconductors” was published by researchers at University of California Los Angeles.

Abstract:

“We investigated low-frequency current fluctuations, i.e. electronic noise, in FePS3 van der Waals, layered antiferromagnetic semiconductor. The noise measurements have been used as noise spectroscopy for advanced materials characterization of the charge carrier dynamics affected by spin ordering and trapping states. Owing to the high resistivity of the material, we conducted measurements on vertical device configuration. The measured noise spectra reveal pronounced Lorentzian peaks of two different origins. One peak is observed only near the Neel temperature and it is attributed to the corresponding magnetic phase transition. The second Lorentzian peak, visible in the entire measured temperature range, has the characteristics of the trap-assisted generation-recombination processes similar to those in conventional semiconductors but shows a clear effect of the spin order reconfiguration near the Neel temperature. The obtained results contribute to understanding the electron and spin dynamics in this type of antiferromagnetic semiconductors and demonstrate the potential of electronic noise spectroscopy for advanced materials characterization.”

Find the technical paper here. Published January 2024 (preprint).

Ghosh, Subhajit, Zahra Ebrahim Nataj, Fariborz Kargar, and Alexander A. Balandin. “Electronic Noise Spectroscopy of Quasi-2D van der Waals Antiferromagnetic Semiconductors.” arXiv preprint arXiv:2401.12432 (2024).

The post Electronic Noise in vdW Layered AFMS (UCLA) appeared first on Semiconductor Engineering.

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