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      Unearthed notebooks shed light on Victorian genius who inspired Einstein

      news.movim.eu / TheGuardian • 15 March

    Michael Faraday’s illustrated notes that show how radical scientist began his theories at London’s Royal Institution to go online

    He was a self-educated genius whose groundbreaking discoveries in the fields of physics and chemistry electrified the world of science and laid the foundations for Albert Einstein’s theory of relativity nearly a century later.

    Now, the little-known notebooks of the Victorian scientist Michael Faraday have been unearthed from the archive of the Royal Institution and are to be digitised and made permanently accessible online for the first time.

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      Small charges in water spray can trigger the formation of key biochemicals

      news.movim.eu / ArsTechnica • 14 March • 1 minute

    We know Earth formed roughly 4.54 billion years ago and that the first single cell lifeforms were present roughly 1 billion years after that. What we don’t know is what triggered the process that turned our planet from a barren ball of rock into a world hosting amazing abundance of lifeforms. “We’re trying to understand how do you go from non-life to life. Now I think we have made a real contribution to solving this mystery,” says Richard Zare, a Stanford University chemistry professor. Zare is the senior author of the recent study into a previously unknown electrochemical process that might have helped supply the raw materials needed for life.

    Zare’s team demonstrated the existence of micro-lightning, very small electricity discharges that occur between tiny droplets of water spray. When triggered in a mixture of gases made to replicate the atmosphere on early Earth, these micro-lightnings produced chemical compounds used by present-day life, like glycine, uracil, and urea, along with chemical precursors like cyanoacetylene, and hydrogen cyanide. “I’m not saying it’s the only way this could happen—I wasn’t there,” Zare acknowledged. “But it’s a new plausible mechanism that gives us building blocks of life.”

    Lightning in the bulb

    Scientific research into the beginnings of life on Earth started in the 1920s with Aleksander Oparin and J.B.S. Haldane, scientists who independently proposed that life on Earth could have arisen through a process of gradual chemical evolution. In their view, inorganic molecules might have reacted due to energy from the Sun or lightning strikes to form life’s building blocks, like amino acids. Those building blocks, Oparin and Haldane argued, could have accumulated in the oceans, making a “primordial soup.”

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      Desalination system adjusts itself to work with renewable power

      news.movim.eu / ArsTechnica • 18 October, 2024 • 1 minute

    Fresh water we can use for drinking or agriculture is only about 3 percent of the global water supply, and nearly 70 percent of that is trapped in glaciers and ice caps. So far, that was enough to keep us going, but severe draughts have left places like Jordan, Egypt, sub-Saharan Africa, Spain, and California with limited access to potable water.

    One possible solution is to tap into the remaining 97 percent of the water we have on Earth. The problem is that this water is saline, and we need to get the salt out of it to make it drinkable. Desalination is also an energy-expensive process. But MIT researchers led by Jonathan Bessette might have found an answer to that. They built an efficient, self-regulating water desalination system that runs on solar power alone with no need for batteries or a connection to the grid.

    Probing the groundwaters

    Oceans are the most obvious source of water for desalination. But they are a good option only for a small portion of people who live in coastal areas. Most of the global population—more or less 60 percent—lives farther than 100 kilometers from the coast, which makes using desalinated ocean water infeasible. So, Bessette and his team focused on groundwater instead.

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      Simple voltage pulse can restore capacity to Li-Si batteries

      news.movim.eu / ArsTechnica • 18 October, 2024 • 1 minute

    If you're using a large battery for a specialized purpose—say grid-scale storage or an electric vehicle—then it's possible to tweak the battery chemistry, provide a little bit of excess capacity, and carefully manage its charging and discharging so that it enjoys a long life span. But for consumer electronics, the batteries are smaller, the need for light weight dictates the chemistry, and the demand for quick charging can be higher. So most batteries in our gadgets start to see serious degradation after just a couple of years of use.

    A big contributor to that is an internal fragmentation of the electrode materials. This leaves some of the electrode material disconnected from the battery's charge handling system, essentially stranding the material inside the battery and trapping some of the lithium uselessly. Now, researchers have found that, for at least one battery chemistry, it's possible to partially reverse some of this decay, boosting the remaining capacity of the battery by up to 30 percent.

    The only problem is that not many batteries use the specific chemistry tested here. But it does show how understanding what's going on inside batteries can provide us with ways to extend their lifespan.

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      Scent of the afterlife? Scientists recreate recipe for Egyptian mummification balm

      news.movim.eu / ArsTechnica • 6 September, 2023 • 1 minute

    Limestone Canopic Jar of the Egyptian lady Senetnay (c. 1450 BCE)

    Enlarge / One of the limestone canopic jars that once held mummified organs of the Egyptian noblewoman Senetnay (c. 1450 BCE). (credit: Museum August Kestner, Hannover/Christian Tepper)

    Trying to recreate the scents and smells of the past is a daunting challenge, given the ephemeral nature of these olfactory cues. Now scientists have identified the compounds in the balms used to mummify the organs of an ancient Egyptian noblewoman, according to a recent paper published in the journal Scientific Reports, suggesting that the recipes were unusually complex and used ingredients not native to the region. The authors also partnered with a perfumer to recreate what co-author Barbara Huber calls "the scent of eternity."

    “'The scent of eternity’ represents more than just the aroma of the mummification process,” said Huber , an archaeologist at the Max Planck Institute of Geoanthropology in Jena, Germany. “It embodies the rich cultural, historical, and spiritual significance of Ancient Egyptian mortuary practices. Our methods were also able to provide crucial insights into balm ingredients for which there is limited information in contemporary ancient Egyptian textual sources.”

    As previously reported , Egyptian embalming is thought to have started in the Predynastic Period or even earlier, when people noticed that the arid heat of the sand tended to dry and preserve bodies buried in the desert. Eventually, the idea of preserving the body after death worked its way into Egyptian religious beliefs. When people began to bury the dead in rock tombs, away from the desiccating sand, they used chemicals like natron salt and plant-based resins for embalming.

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      The room-temperature superconductor that wasn’t

      news.movim.eu / ArsTechnica • 6 September, 2023

    Image of a gold-colored cube floating in a foggy environment above a grey metal plate.

    Enlarge / Levitation like this will apparently continue to require extremely cold temperatures for now. (credit: ClaudeLux )

    The summer of room-temperature superconductivity was short-lived. It started with some manuscripts placed on the arXiv toward the end of July, which purportedly described how to synthesize a compound called LK-99, which would act as a superconductor at temperatures above the boiling point of water. High enough that, if its synthesis and material properties worked out, it could allow us to replace metals with superconductors in a huge range of applications.

    Confusion quickly followed, as the nature of the chemical involved made it difficult to know when you were looking at the behavior of LK-99 and when you were looking at related chemicals or even impurities.

    But the materials science community responded remarkably quickly. By the end of August, pure samples had been prepared, the role of impurities explored, and a strong consensus had developed: LK-99 was not a superconductor. Best yet, the work nicely provided explanations for why it had behaved a bit like one in a number of situations.

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      Vlad the Impaler may have shed tears of blood, study finds

      news.movim.eu / ArsTechnica • 21 August, 2023 • 1 minute

    This letter written by Vlad the Impaler in 1475 contains proteins that suggest he suffered from respiratory problems and bloodied tears.

    Enlarge / This 1475 letter written by Vlad the Impaler contains proteins suggesting he suffered from respiratory problems, bloodied tears. (credit: Adapted from M.G.G. Pittala et al., 2023/CC BY )

    The eponymous villain of Bram Stoker's classic 1897 novel Dracula was partly inspired by a real historical person: Vlad III, a 15th century prince of Wallachia (now southern Romania), known by the moniker Vlad the Impaler because of his preferred method of execution: impaling his victims on spikes. Much of what we know about Vlad III comes from historical documents, but scientists have now applied cutting-edge proteomic analysis to three of the prince's surviving letters, according to a recent paper published in the journal Analytical Chemistry. Among their findings: the Romanian prince was not a vampire, but he may have wept tears of blood, consistent with certain legends about Vlad III.

    Vlad III was the second son of Vlad Dracul ("the Dragon"), who became the voivode of Wallachia in 1436. Vlad III was also known as Vlad Dracula ("son of the Dragon"), and it was this name that Stoker used for his fictional vampire— dracul means "the devil" in modern Romanian—along with a few historical details he was able to glean about Wallachia. This was a brutal, bloody period of political instability. Vlad spent several years as a prisoner of the Ottoman Empire, along with his younger brother Radu, and his father and older brother, Mircea, were murdered in 1447. Eventually, Vlad became voivode of Wallachia himself—three times, in fact, interrupted by periods of exile or captivity.

    Vlad was constantly at war, and it was his brutal treatment of his enemies that led to his reputation as a monster, particularly in German-speaking territories, where books detailing his atrocities became bestsellers. These accounts described how Vlad executed men, women, and children taken prisoner from a Saxon village and impaled them. The more accurate, eye-witness-based accounts also included details about the churches Vlad's army destroyed during plundering raids in Transylvania. Other stories (many likely exaggerated) claimed he burned the lazy and the poor, and had women impaled along with their nursing babies. A well-known woodcut shows Vlad dining while surrounded by impaled people on poles. He died in battle in January 1477, having killed an estimated 80,000 people in his lifetime.

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      When it comes to keeping the fizz in your champagne, bottle size matters

      news.movim.eu / ArsTechnica • 28 July, 2023 • 1 minute

    French physicist Gerard Liger-Belair studied CO₂ levels in 13 old champagne vintages in three different bottle sizes.

    Enlarge / French physicist Gerard Liger-Belair studied CO₂ levels in 13 old champagne vintages in three different bottle sizes. (credit: Andy Roberts/Getty Images)

    A large part of the pleasure of imbibing a glass of champagne comes from its effervescence: all those bubbles rising from the glass and ticking the nose and palate. If there's no fizz, there's no fun—and also less flavor and aromas to savor. A recent paper published in the journal ACS Omega found that the size of the champagne bottle is a key factor in determining when the wine inside will go flat.

    As we've reported previously , champagne's effervescence arises from the nucleation of bubbles on the glass walls. Once they detach from their nucleation sites, the bubbles grow as they rise to the liquid surface, where they burst. This typically occurs within a couple of milliseconds, and the distinctive crackling sound is emitted when the bubbles rupture. The bubbles even "ring" at specific resonant frequencies , depending on their size, so it's possible to "hear" the size distribution of bubbles as they rise to the surface in a glass of champagne.

    Prior studies have shown that when the bubbles in champagne burst, they produce droplets that release aromatic compounds believed to enhance the flavor. Larger bubbles enhance the release of aerosols into the air above the glass—bubbles on the order of 1.7 mm across at the surface. French physicist Gerard Liger-Belair of the University of Reims Champagne-Ardenne is one of the foremost scientists studying many different aspects of champagne and has now turned his attention to exploring how long champagne can age in the bottle before the carbonation dissipates to the point where those all-important bubbles can no longer form.

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      Rover sampling finds organic molecules in water-altered rocks

      news.movim.eu / ArsTechnica • 12 July, 2023 • 1 minute

    Greyscale image of a large fan of material spread out across a crater floor.

    Enlarge / Jezero crater shows clear signs of water-formed deposits, so it's not a surprise to find water-altered material there. (credit: NASA/MSSS/USGS )

    Organic chemicals, primarily composed of carbon and hydrogen, underly all of life. They're also widespread in the Universe, so they can't be taken as a clear signature of the presence of life. That creates an annoying situation regarding the search for evidence of life on Mars, which clearly has some organic chemicals despite the harsh environment.

    But we don't know whether these are the right kinds of molecules to be indications of life. For the moment, we also lack the ability to tear apart Martian rocks, isolate the molecules, and figure out exactly what they are. In the meantime, our best option is to get some rough information on them and figure out the context of where they're found on Mars. And a big step has been made in that direction with the publication of results from imaging done by the Perseverance rover.

    Ask SHERLOC

    The instrument that's key to the new work has a name that pretty much tells you it was designed to handle this specific question: Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals (SHERLOC). SHERLOC comes with a deep-UV laser to excite molecules into fluorescing, and the wavelengths they fluoresce at can tell us something about the molecules present. It's also got the hardware to do Raman spectroscopy simultaneously.

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