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Categories: Chemistry: Inorganic Chemistry, Paleontology: Climate

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Friction is hard to predict and control, especially since surfaces that come in contact are rarely perfectly flat. New experiments demonstrate that the amount of friction between two silicon surfaces, even at large scales, is determined by the forming and rupturing of microscopic chemical bonds between them. This makes it possible to control the amount of friction using surface chemistry techniques.

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A collaborative research team has discovered a new process for making anhydrides that promises improvements in costs and sustainability.

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Identifying how and why Antarctica's major ice sheets behaved the way they did in the early Miocene could help inform understanding of the sheets' behavior under a warming climate. Together, the ice sheets lock a volume of water equivalent to more than 50 meters of sea level rise and influence ocean currents that affect marine food webs and regional climates. Their fate has profound consequences for life nearly everywhere on Earth.  

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Long before researchers discovered the electron and its role in generating electrical current, they knew about electricity and were exploring its potential. One thing they learned early on was that metals were great conductors of both electricity and heat. And in 1853, two scientists showed that those two admirable properties of metals were somehow related: At any given temperature, the ratio of electronic conductivity to thermal conductivity was roughly the same in any metal they tested. This so-called Wiedemann-Franz law has held ever since -- except in quantum materials. Now, a theoretical argument put forth by physicists suggests that the law should, in fact, approximately hold for one type of quantum material, the cuprate superconductors.

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A recent study demonstrates how dripstones can be crucial for reconstructing past climates. The new approach can provide a detailed picture of the climate around early human occupations in South Africa.

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To ensure that vaccines provide strong and lasting immunization, it is often necessary to supplement the actual vaccine (antigen) with additives that stimulate the immune system: adjuvants. Today, only a few substances have been approved for use as adjuvants. A research team has now introduced a spectrum of potential adjuvants. They started with the immune stimulant ?-glactosyl ceramide (?-GalCer) and synthesized many different variants from a set of four building blocks.

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Found in fishing nets, carpet, clothing, Nylon-6 is a major contributor to plastic pollution, including ocean pollution. Now, chemists have developed a new catalyst that quickly, cleanly and completely breaks down Nylon-6 in a matter of minutes -- without generating harmful byproducts. Even better: The process does not require toxic solvents, expensive materials or extreme conditions, making it practical for everyday applications. In experiments, the new process recovered 99% of the polymer's building blocks, which can then be upcycled into higher-value products.

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The San Joaquin Valley in California has experienced vast variability in climate extremes, with droughts and floods that were more severe and lasted longer than what has been seen in the modern record, according to a new study of 600 years of tree rings from the valley.

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Researchers have developed an AI model that can predict where a drug molecule can be chemically altered.

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Used lithium-ion batteries from cell phones, laptops and a growing number of electric vehicles are piling up, but options for recycling them remain limited mostly to burning or chemically dissolving shredded batteries. Researchers have improved on approaches that dissolve the battery in a liquid solution in order to reduce the amount of hazardous chemicals used in the process. This simple, efficient and environmentally-friendly solution overcomes the main obstacles presented by previous approaches.

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A landmark study into the geological timescale distribution of sediment and nutrients over 500 million years shows that species biodiversity on Earth is driven by landscape dynamics.

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Researchers have demonstrated a compact particle accelerator less than 20 meters long that produces an electron beam with an energy of 10 billion electron volts (10 GeV). There are only two other accelerators currently operating in the U.S. that can reach such high electron energies, but both are approximately 3 kilometers long. This type of accelerator is called a wakefield laser accelerator.

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Scientists have made a surprising discovery that sheds new light on the role that oceanic deoxygenation (anoxia) played in one of the most devastating extinction events in Earth's history. Their finding has implications for current day ecosystems -- and serves as a warning that marine environments are likely more fragile than apparent. New research, published today in leading international journal Nature Geosciences, suggests that oceanic anoxia played an important role in ecosystem disruption and extinctions in marine environments during the Triassic--Jurassic mass extinction, a major extinction event that occurred around 200 million years ago.  Surprisingly however, the study shows that the global extent of euxinia (an extreme form of de-oxygenated conditions) was similar to the present day.

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Researchers have devised a way to produce chemicals used in medicine and agriculture for a fraction of the usual cost. Using oxygen as a reagent and copper as a catalyst to break organic molecules' carbon-carbon bonds and convert them into amines, which are widely used in pharmaceuticals. Traditional metal catalysis uses expensive metals such as platinum, silver, gold and palladium, but the researchers used oxygen and copper -- an abundant base metal.

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Researchers create transistors combining silicon with biological silk, using common microprocessor manufacturing methods. The silk protein can be easily modified with other chemical and biological molecules to change its properties, leading to circuits that respond to biology and the environment.

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Glass is a fundamental material. Yet its atomic structure still baffles scientists to this day. Researchers have developed a new way to quantify ring shapes in chemically bonded networks of glass, chipping away at some of the mysteries behind glass's atomic structure.  

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Global measurements and model calculations show that the complex relationship between the chemistry and climate impact of aerosol particles can be successfully captured by a simple formula.

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Using historical records from around Australia, an international team of researchers have put forward the most accurate prediction to date of past Antarctic ice sheet melt, providing a more realistic forecast of future sea level rise.   The Antarctic ice sheet is the largest block of ice on earth, containing over 30 million cubic kilometers of water.   Hence, its melting could have a devasting impact on future sea levels. To find out just how big that impact might be, the research team turned to the past.  

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Bio-based plastics often end up in recycling streams because they look and feel like conventional plastic, but the contamination of these compostable products makes it much harder to generate functional material out of recycled plastic. Scientists have now developed a biology-driven process to convert these mixtures into a new biodegradable material that can be used to make fresh products. The scientists believe the process could also enable a new field of biomanufacturing wherein valuable chemicals and even medicines are made from microbes feeding off of plastic waste.

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Chemists have developed a bioinspired supramolecular approach to convert photo-switchable molecules from their stable state into metastable one with low-energy red light. Their work enables fast, highly selective, and efficient switching, providing new tools for energy storage, activation of drugs with light, and sensing applications.