Chemistry news and discussions

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Metallic bond between two beryllium atoms made for the first time
https://phys.org/news/2023-06-metallic- ... atoms.html
by Bob Yirka , Phys.org

A quartet of chemists at the University of Oxford has, for the first time, found a way to get two beryllium atoms to bond with one another. In their paper published in the journal Science, Josef Boronski, Agamemnon Crumpton, Lewis Wales and Simon Aldridge, describe their process and how they managed to do it in a safe way—and at room temperature. Jason Dutton with La Trobe University, has published a Perspective piece in the same journal issue, outlining the work done by the team in England.

Beryllium is a strong but lightweight, alkaline earth metal. It is also brittle.

Beryllium only ever occurs naturally when mixed with other elements, forming minerals. It is often found in gemstones such as emeralds. And it is used in a variety of applications, from telecommunications equipment to computers and cell phones. It is also mixed with other metals to create alloys used in applications such as gyroscopes and electrical contacts.

For many years, scientists have thought that the element could be even more useful if a way could be found to force beryllium atoms to bond with one another. But until now, it was not possible.

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Scientists develop a new class of artificial water channels for more efficient industrial water purification
https://phys.org/news/2023-08-scientist ... cient.html
by National University of Singapore

A team led by scientists from the National University of Singapore's (NUS) Department of Biological Sciences in collaboration with the French Center for Scientific Research (CNRS) has successfully synthesized a special protein-mimic that can self-assemble into a pore structure. When incorporated into a lipid membrane, the pores permit selective transport of water across the membrane while rejecting salt (ions).

These protein-mimics, known as 'oligourea foldamers,' represent an entirely new class of artificial water channels (AWC) that can be used to improve the energy-efficiency of current methods of industrial water purification.

Current methods of water purification involve the use of reverse osmosis and membrane distillation technologies. Reverse osmosis, however, is a highly energy-intensive process as high pressures are needed to pass seawater or wastewater through a series of semi-permeable membranes to remove salts and other pollutants.

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New, simple and accessible method creates potency-increasing structure in drugs
https://phys.org/news/2023-08-simple-ac ... drugs.html
by Pennsylvania State University

Chemical structures called cyclopropanes can increase the potency and fine-tune the properties of many drugs, but traditional methods to create this structure only work with certain molecules and require highly reactive—potentially explosive—ingredients.

Now, a team of researchers from Penn State has identified and demonstrated a safe, efficient and practical way to create cyclopropanes on a wide variety of molecules using a previously undescribed chemical process. With additional development, the new method—described in a paper publishing Aug. 4 in the journal Science—could transform how this important process occurs during drug development and creation.

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Pivotal discovery in sensor technology eliminates faulty electronic sensors when measuring toxins in water
https://phys.org/news/2023-08-pivotal-d ... aulty.html
by Joseph E. Harmon, Argonne National Laboratory

There is a global water crisis, and it is not only about the dwindling supply of clean water. Contaminated drinking water exposes hundreds of millions of people worldwide to toxins, such as bacteria, heavy metals, pesticides and coronaviruses. This contamination imperils public health and can cause serious illnesses.

A team of researchers from the U.S. Department of Energy's Argonne National Laboratory, along with the Pritzker School of Molecular Engineering at the University of Chicago and the University of Wisconsin—Milwaukee, has devised a pathway for the mass manufacture of sensors able to simultaneously detect lead, mercury and E. coli. in flowing tap water. The team's innovation promises to help safeguard public health by providing early warning for contamination.

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Scientists theorize a hidden phase transition between liquid and a solid
https://phys.org/news/2023-08-scientist ... ition.html
by Rachel Berkowitz, Lawrence Berkeley National Laboratory

Anything made out of plastic or glass is known as an amorphous material. Unlike many materials that freeze into crystalline solids, the atoms and molecules in amorphous materials never stack together to form crystals when cooled. In fact, although we commonly think of plastic and glass as "solids," they instead remain in a state that is more accurately described as a supercooled liquid that flows extremely slowly.

And although these "glassy dynamic" materials are ubiquitous in our daily lives, how they become rigid at the microscopic scale has long eluded scientists.

Now, researchers at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have discovered molecular behavior in supercooled liquids that represents a hidden phase transition between a liquid and a solid.

Their improved understanding applies to ordinary materials like plastics and glass, and could help scientists develop new amorphous materials for use in medical devices, drug delivery, and additive manufacturing.

Specifically, using theory, computer simulations, and previous experiments, the scientists explained why the molecules in these materials, when cooled, remain disordered like a liquid until taking a sharp turn toward a solid-like state at a certain temperature called the onset temperature—effectively becoming so viscous that they barely move. This onset of rigidity—a previously unknown phase transition—is what separates supercooled from normal liquids.

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Not sure if this is the right place to post this, but they made a super-strong eco-friendly glass.

https://www.bbc.com/news/business-66359047

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A new way to identify chiral molecules with light could vastly improve detection efficiency
https://phys.org/news/2023-08-chiral-mo ... iency.html
by Imperial College London

Chiral molecules are those that have two versions that are mirror images, like our right and left hands. These molecules have the same structure but different properties when they interact with other molecules, including those inside our bodies. This is important for example in drug molecules, where only the right- or left-handed version may have the desired effect.

Detecting and quantifying the chirality of matter however has been difficult. Current methods using a form of light that produces a (right- or left-twisting) helix have the problem that each turn of the helix is much larger than the molecules. This creates important challenges for

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Machine learning tool simplifies one of the most widely used reactions in the pharmaceutical industry
https://phys.org/news/2023-09-machine-t ... tical.html
by Tracy Crane, University of Illinois at Urbana-Champaign

In the past two decades, the carbon-nitrogen bond forming reaction, known as the Buchwald-Hartwig reaction, has become one of the most widely used tools in organic synthesis, particularly in the pharmaceutical industry given the prevalence of nitrogen in natural products and pharmaceuticals.

This powerful reaction has revolutionized the way nitrogen-containing compounds are made in academic and industrial laboratories, but it requires lengthy, time-consuming experimentation to determine the best conditions for a highly effective reaction.

Now, Illinois researchers in collaboration with chemists at Hoffman La-Roche, a pharmaceutical company in Switzerland, have developed a machine learning tool that predicts in a matter of minutes the best conditions for a high-yielding reaction with no lengthy experimentation.

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Reducing the carbon footprint of methane by converting it into methanol with a new enzyme
https://phys.org/news/2023-09-carbon-fo ... nzyme.html
by Nagoya University

A team led by Professor Osami Shoji at Nagoya University in Japan has developed a technology to convert methane, the principal component of natural gas, into methanol at room temperature in water. They used an enzyme that can be easily mass-produced, offering the possibility of a cheap and effective means to reduce the carbon footprint of natural gas. They published the results in ACS Catalysis.

Methane is the key component of natural gas and an abundant natural resource. However, it is chemically stable, requiring huge amounts of energy before it undergoes chemical conversion. One solution is to convert methane to methanol.

Methane can be converted to methanol, which is cleaner than other fossil fuels and can be easily stored and transported. Converting methane to methanol can be done using the methane monooxygenase enzyme. However, the enzyme has a complex structure, making it difficult to handle and unsuitable for mass production.

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Scientists finally detected O-28. It's instability surprised them
https://www.sciencenews.org/article/oxy ... se-physics

Using a powerful particle accelerator, researchers have spotted an elusive variant of oxygen for the first time. The isotope, oxygen-28, was predicted to be stable thanks to its eight protons and 20 neutrons — “magic” numbers associated with extra stability in atomic nuclei.

Atomic nuclei are made up of protons and neutrons, each of which are thought to occupy their own “shells” — discrete energy levels that are separated by large energy gaps. Atomic nuclei with full outer shells are bound extra tightly, making them very stable. Shells fill up when they hit two, eight, 20, 28, 50, 82 and 126 subatomic particles (SN: 10/9/13).

Finding the isotope took a combination of brute force and experimental elegance. Physicist Yosuke Kondo of the Tokyo Institute of Technology and colleagues used a particle accelerator to smash calcium-48 atoms against a beryllium target. This fragmented the calcium-48 atoms into lighter isotopes, including fluorine-29. Throwing the fluorine-29 against a liquid hydrogen target knocked off a single proton, producing oxygen-28.”

Scientists expected the isotope to be stable, but it isn’t: it sloughs off 4 neutrons in a femtosecond (1E-21 sec). O-28’s surprising instability indicates there’s something we don’t understand about the strong nuclear force, which binds together protons and neutrons in the atomic nucleus.