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Tag: Chemistry

  • Using Machine Learning to Better Understand How Water Behaves

    Using Machine Learning to Better Understand How Water Behaves

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    Newswise — Water has puzzled scientists for decades. For the last 30 years or so, they have theorized that when cooled down to a very low temperature like -100C, water might be able to separate into two liquid phases of different densities. Like oil and water, these phases don’t mix and may help explain some of water’s other strange behavior, like how it becomes less dense as it cools.

    It’s almost impossible to study this phenomenon in a lab, though, because water crystallizes into ice so quickly at such low temperatures. Now, new research from the Georgia Institute of Technology uses machine learning models to better understand water’s phase changes, opening more avenues for a better theoretical understanding of various substances. With this technique, the researchers found strong computational evidence in support of water’s liquid-liquid transition that can be applied to real-world systems that use water to operate.

    “We are doing this with very detailed quantum chemistry calculations that are trying to be as close as possible to the real physics and physical chemistry of water,” said Thomas Gartner, an assistant professor in the School of Chemical and Biomolecular Engineering at Georgia Tech. “This is the first time anyone has been able to study this transition with this level of accuracy.”

    The research was presented in the paper, “Liquid-Liquid Transition in Water From First Principles,” in the journal Physical Review Letters, with co-authors from Princeton University.

    Simulating Water

    To better understand how water interacts, the researchers ran molecular simulations on supercomputers, which Gartner compared to a virtual microscope.

    “If you had an infinitely powerful microscope, you could zoom in all the way down to the level of the individual molecules and watch them move and interact in real time,” he said. “This is what we’re doing by creating almost a computational movie.”

    The researchers analyzed how the molecules move and characterized the liquid structure at different water temperatures and pressures, mimicking the phase separation between the high and low-density liquids. They collected extensive data — running some simulations for up to a year — and continued to fine-tune their algorithms for more accurate results.

    Even a decade ago, running such long and detailed simulations wouldn’t have been possible, but machine learning today offered a shortcut. The researchers used a machine learning algorithm that calculated the energy of how water molecules interact with each other. This model performed the calculation significantly faster than traditional techniques, allowing the simulations to progress much more efficiently.

    Machine learning isn’t perfect, so these long simulations also improved the accuracy of the predictions. The researchers were careful to test their predictions with different types of simulation algorithms. If multiple simulations gave similar results, then it validated their accuracy.

    “One of the challenges with this work is that there’s not a lot of data that we can compare to because it’s a problem that’s almost impossible to study experimentally,” Gartner said. “We’re really pushing the boundaries here, so that’s another reason why it’s so important that we try to do this using multiple different computational techniques.”

    Beyond Water

    Some of the conditions the researchers tested were extremes that probably don’t exist on Earth directly, but potentially could be present in various water environments of the solar system, from the oceans of Europa to water in the center of comets. Yet these findings could also help researchers better explain and predict water’s strange and complex physical chemistry, informing water’s use in industrial processes, developing better climate models, and more.  

    The work is even more generalizable, according to Gartner. Water is a well-studied research area, but this methodology could be expanded to other difficult-to-simulate materials like polymers, or complex phenomena like chemical reactions.

    “Water is so central to life and industry, so this particular question of whether water can undergo this phase transition has been a longstanding problem, and if we can move toward an answer, that’s important,” he said. “But now we have this really powerful new computational technique, but we don’t yet know what the boundaries are and there’s a lot of room to move the field forward.”

    CITATION: T.E. Gartner, III, P.M. Piaggi, R. Car, A.Z. Panagiotopoulos, P.G. Debenedetti, “Liquid-liquid transition in water from first principles,”* Phys. Rev. Lett., 2022.

    DOI:10.1103/PhysRevLett.129.255702

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    The Georgia Institute of Technology, or Georgia Tech, is one of the top public research universities in the U.S., developing leaders who advance technology and improve the human condition. The Institute offers business, computing, design, engineering, liberal arts, and sciences degrees. Its more than 46,000 students, representing 50 states and more than 150 countries, study at the main campus in Atlanta, at campuses in France and China, and through distance and online learning. As a leading technological university, Georgia Tech is an engine of economic development for Georgia, the Southeast, and the nation, conducting more than $1 billion in research annually for government, industry, and society. 

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    Georgia Institute of Technology

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  • An integrated, net-negative system captures carbon and produces ethylene

    An integrated, net-negative system captures carbon and produces ethylene

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    Newswise — Engineers at the University of Illinois Chicago have built a machine that captures carbon from flue gas and converts it to ethylene.  

    The device integrates a carbon capture system with an ethylene conversation system for the first time. And, the system not only runs on electricity, but it also removes more carbon from the environment than it generates – making it what scientists call net-negative on carbon emissions. 

    Among manufactured chemicals worldwide, ethylene ranks third for carbon emissions after ammonia and cement. Ethylene is used not only to create plastic products for the packaging, agricultural and automotive industries but also to produce chemicals used in antifreeze, medical sterilizers and vinyl siding for houses, for example.  

    The system and the results of the UIC College of Engineering scientists’ experiments are published in an Energy & Environmental Science paper titled “Fully-Integrated Electrochemical System that Captures CO2 from Flue Gas to Produce Value-Added Chemicals at Ambient Conditions.” 

    “This is the first demonstration of a net-negative, all-electric integrated system to capture carbon from pollutants and create a highly valuable resource,” said Meenesh Singh, UIC assistant professor in the department of chemical engineering. 

    “There is an urgent need to develop efficient technologies for integrated carbon capture and conversion to sustainably produce net-negative fuels. Currently, integrated carbon capture and conversion systems are highly energy-intensive and work in a discontinuous cycle of carbon dioxide capture and reduction. Efficiently integrating carbon capture with the conversion system eliminates the need for transportation and storage, and thereby increasing its energy efficiency.” 

    The integrated carbon capture and conversion system developed at UIC continuously captures carbon dioxide from flue gas to produce high-purity ethylene.  

    “This is an important milestone in ethylene decarbonization,” Singh said.  

    To capture carbon from the air or flue gas, Singh’s lab modified a standard artificial leaf system with inexpensive materials to include a water gradient — a dry side and a wet side — across an electrically charged membrane.  

    On the dry side, an organic solvent attaches to available carbon dioxide to produce a concentration of bicarbonate, or baking soda, on the membrane. As bicarbonate builds, these negatively charged ions are pulled across the membrane toward a positively charged electrode in a water-based solution on the membrane’s wet side. The liquid solution dissolves the bicarbonate back into carbon dioxide, so it can be released and harnessed for CO2 conversion.  

    The system uses a modular, stackable design that allows the system to be easily scaled up and down. 

    To convert captured carbon dioxide to ethylene, Singh and his colleagues used a second system in which an electric current is passed through a cell. Half of the cell is filled with carbon dioxide captured from a carbon capture system, the other half with a water-based solution. An electrified catalyst draws charged hydrogen atoms from the water molecules into the other half of the unit separated by a membrane, where they combine with charged carbon atoms from the carbon dioxide molecules to form ethylene.  

    The UIC researchers integrated the two systems by feeding the captured carbon dioxide solution to the carbon conversion system and recycling it back. The closed-loop recycling of solution ensures a constant supply of carbon dioxide from flue gas and its conversion to ethylene. 

    To test their integrated system, the researchers implemented a 100-square-centimeters bipolar membrane electrodialysis unit to capture carbon dioxide from the flue gas and hydraulically connected it to the 1-square-centimeter electrolysis cell to produce ethylene.  

    They were able to test the system continuously, 24 hours per day for seven days. The system was not only stable the entire time, it also captured carbon at a rate of 24 grams per day and produced ethylene at a rate of 188 milligrams per day. 

    “In the journey to make ethylene production green, this is a potential breakthrough,” Singh said. “Our next step is to scale up the integrated carbon capture and conversion system to produce ethylene at higher rates — a rate of 1 kilogram per day and capture carbon at a rate higher than kilograms per day.” 

    Co-authors of the study include Aditya Prajapati and Rohan Sartape of UIC, and Miguel Galante, Jiahan Xie, Samuel Leung, Ivan Bessa, Marcio Andrad, Robert Somich, Marcio Reboucas, Gus Hutras and Nathalia Diniz of Braskem. Research to develop this technology has received support from the U.S. Department of Energy (DE-SC-0022321) and Braskem. 

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    University of Illinois Chicago

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  • Recycled gold from SIM cards could help make drugs more sustainable

    Recycled gold from SIM cards could help make drugs more sustainable

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    Newswise — Researchers have used gold extracted from electronic waste as catalysts for reactions that could be applied to making medicines.

    Re-using gold from electronic waste prevents it from being lost to landfill, and using this reclaimed gold for drug manufacture reduces the need to mine new materials. Current catalysts are often made of rare metals, which are extracted using expensive, energy-intensive and damaging mining processes.

    The method for extracting gold was developed by researchers at the University of Cagliari in Italy and the process for using the recovered gold was developed by researchers at Imperial College London. The study is published in ACS Sustainable Chemistry & Engineering.

    Waste electrical and electronic equipment (WEEE) is typically sent to landfill, as separating and extracting the components requires a lot of energy and harsh chemicals, undermining its economic viability. However, WEEE contains a wealth of metals that could be used in a range of new products.

    Finding ways to recover and use these metals in a low-cost, low-energy and non-toxic way is therefore crucial for making our use of electronic goods more sustainable.

    Lead researcher Professor James Wilton-Ely, from the Department of Chemistry at Imperial, said: “It is shocking that most of our electronic waste goes to landfill and this is the opposite of what we should be doing to curate our precious elemental resources. Our approach aims to reduce the waste already within our communities and make it a valuable resource for new catalysts, thereby also reducing our dependence on environmentally damaging mining practices.”

    “We are currently paying to get rid of electronic waste, but processes like ours can help reframe this ‘waste’ as a resource. Even SIM cards, which we routinely discard, have a value and can be used to reduce reliance on mining and this approach has the potential to improve the sustainability of processes such as drug manufacture.”

    Professors Angela Serpe and Paola Deplano, from the University of Cagliari, developed a low-cost way to extract gold and other valued metals from electronic waste such as printed circuit boards (PCBs), SIM cards and printer cartridges under mild conditions. This patented process involves selective steps for the sustainable leaching and recovery of base metals like nickel, then copper, silver and, finally, gold, using green and safe reagents.

    However, the gold produced from this process is part of a molecular compound and so cannot be re-used again for electronics without investing a lot more energy to obtain the gold metal. Seeking a use for this compound of recovered gold, the team of Professor Wilton-Ely and his colleague, Professor Chris Braddock, investigated whether it could be applied as a catalyst in the manufacture of useful compounds, including pharmaceutical intermediates.

    Catalysts are used to increase the rate of a chemical reaction while remaining unchanged and are used in most processes to produce materials. The team tested the gold compound in a number of reactions commonly used in pharmaceutical manufacture, for example for making anti-inflammatory and pain-relief drugs.

    They found that the gold compound performed as well, or better, than the currently used catalysts, and is also reusable, further improving its sustainability.

    The researchers suggest that making it economically viable to recover gold from electronic waste could create spin-off uses for other components recovered in the process. For example, in the process, copper and nickel are also separated out, as is the plastic itself, with all these components potentially being used in new products.

    Sean McCarthy, the PhD student leading the research in the lab at Imperial, said: “By weight, a computer contains far more precious metals than mined ore, providing a concentrated source of these metals in an ‘urban mine’.”

    Professor Serpe said: “Research like ours aims to contribute to the cost-effective and sustainable recovery of metals by building a bridge between the supply of precious metals from scrap and industrial demand, bypassing the use of virgin raw materials.”

    The teams are working to extend this approach to the recovery and re-use of the palladium content of end-of-life automotive catalytic converters. This is particularly pressing as palladium is widely used in catalysis and is even more expensive than gold.

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    Imperial College London

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  • Microphytobenthos in the Dutch Wadden Sea feeds on ‘left-overs’ in the bottom

    Microphytobenthos in the Dutch Wadden Sea feeds on ‘left-overs’ in the bottom

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    Isotopes
    Newswise — For the study, Riekenberg and colleagues looked at the chemical variations in the isotopes of nitrogen. There are two predominate forms of nitrogen, ‘nitrogen-14’ and the heavier version, ‘nitrogen-15’. When an organism digests protein, for example from plankton, the resulting nitrogen is used to create its own proteins. In this process, the lighter nitrogen-14 is lost a bit, so the relative concentration of the heavy nitrogen increases a little at each step in the food chain. As a result, animals higher up the food chain retain relatively more and more nitrogen-15.

    Individual amino acids
    In recent years, it has become possible to also analyze the different nitrogen isotopes from individual amino acids. Certain amino acids (the building blocks of protein) cannot be created by higher organisms themselves. As a result, those essential or ‘source amino acids’ need to be obtained from the diet and remain mostly unchanged throughout the food chain. Therefore, in these amino acids, the stable isotope ratio of nitrogen does not become progressively higher with each step of eating or being eaten. Other, so-called trophic amino acids do change a lot during metabolism through each step of the food chain. Thus, the difference in nitrogen composition between trophic and essential amino acids provides a measure of how high up the food chain an organism is, independent of any variations in underlying nitrogen sources supporting the ecosystem. We used this technique to build a trophic structure from direct measurements of the Dutch Wadden Sea food web.   

    Detritus in the pore water
    Using samples that were collected between 2011 and 2014 during the long-lasting monitoring program of NIOZ, SIBES (the Synoptic Intertidal BEnthic Survey), Riekenberg analyzed the nitrogen isotopes of amino acids from 340 different animals from across the Dutch Wadden Sea. Thus, he was able to trace back the sources of nitrogen that these animals used. Riekenberg: “We saw that quite a bit of the nitrogen did not come from the overlying water column, but from the benthic primary producers, like diatoms, using nitrogen from the pore water at the bottom of the Wadden Sea. This nitrogen has a distinct signal, since it is what remains after the breaking down of organic matter and denitrification, and can therefore be tracked into a portion of the food web.”

    Ecological models
    Riekenberg stresses that this new piece of the jigsaw adds important knowledge to the science of the Wadden Sea ecosystem. “Now that we know that detrital nitrogen in porewaters is an important direct source of nutrients, this should be included in ecological models we make of the Wadden Sea. If our models do not include all pools of nutrients supporting the food web, then how can these models accurately reflect the ecology of the Wadden Sea when they are used to predict future impacts or changes?”

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    Royal Netherlands Institute for Sea Research

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  • American Chemical Society announces new CEO: Albert G. Horvath

    American Chemical Society announces new CEO: Albert G. Horvath

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    Newswise — The American Chemical Society (ACS) Board of Directors has selected Albert G. Horvath, Treasurer and Chief Financial Officer (CFO) at ACS, as the Society’s next CEO, effective Jan. 1, 2023. He succeeds Thomas Connelly Jr., who is retiring after nearly eight years with ACS.

    “I am pleased that a person with Al Horvath’s skill will be the next CEO of ACS,” says Paul W. Jagodzinski, chair of the ACS Board of Directors. “His dedication to the mission and core values of ACS, coupled with his experience in member and public-serving organizations, position him well to lead the Society as we move forward.”

    “I am honored and humbled to have been selected for this role and greatly appreciative to the Board for its confidence in me,” says Horvath. “I have developed a deep commitment to ACS, and I look forward to working with our talented team in serving our members, customers and the entire chemistry enterprise. Together with our volunteers, I am confident that we will achieve the Society’s bold vision.”

    Prior to joining ACS in 2019, Horvath served as Chief Operating Officer and Under Secretary for Finance and Administration at the Smithsonian Institution. There, he oversaw more than 2,200 employees in various Smithsonian offices, including facilities and maintenance, human resources, security, commercial enterprises and financial operations. He joined the Smithsonian in 2011 and served as its Acting Secretary for six months in 2015. In this role, he worked closely with museum and research center directors to bring the Smithsonian’s vast resources — spanning history, art, culture and science — to the citizens of the U.S. and visitors from around the world.

    Horvath’s tenure at the Smithsonian was preceded by more than two decades working in senior leadership roles for some of the leading research universities in the country. He was the Vice President for Finance and Business at the Pennsylvania State University (Penn State), his alma mater, for two years before being named Senior Vice President for Finance and Business/Treasurer. He was responsible for financial, endowment, business and administrative activities at all Penn State campuses, with a $4.2 billion operating budget.

    Before joining Penn State, Horvath was Executive Vice President of Finance and CFO at Columbia University (2004–07), where he had oversight for all financial activities of the university, including the medical center, and developed a five-year capital plan and debt strategy. And prior to that, he worked at the California Institute of Technology, where he served as the Associate Vice President for Finance and Controller in 2000, before becoming the Vice President for Business and Finance/CFO in 2001, a position he held until joining Columbia University.

    From 1994 until 2000, he was Controller at New York University, having previously served in senior roles at Carnegie Mellon University (1988–94). He began his career at Mellon Bank (1981–88) in his hometown of Pittsburgh before moving into higher education.

    “Throughout his career, Al has held leadership roles in distinguished organizations committed to scientific advancement,” says Connelly. “His broad experience and personal qualities make him the ideal leader of ACS.”

    A native of Pennsylvania, Horvath earned his master’s degree in business administration at Duquesne University in 1985 and his bachelor’s degree in accounting at Penn State in 1981. He has served on numerous boards of directors, including the Smithsonian Channel, Green Door, Penn State Hershey Medical Center and Council on Governmental Relations, among others.

    The American Chemical Society (ACS) is a nonprofit organization chartered by the U.S. Congress. ACS’ mission is to advance the broader chemistry enterprise and its practitioners for the benefit of Earth and all its people. The Society is a global leader in promoting excellence in science education and providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, eBooks and weekly news periodical Chemical & Engineering News. ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a leader in scientific information solutions, its CAS division partners with global innovators to accelerate breakthroughs by curating, connecting and analyzing the world’s scientific knowledge. ACS’ main offices are in Washington, D.C., and Columbus, Ohio.

    To automatically receive news releases from the American Chemical Society, contact [email protected].

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    American Chemical Society (ACS)

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  • Plants employ chemical engineering to manufacture bee-luring optical devices

    Plants employ chemical engineering to manufacture bee-luring optical devices

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    Newswise — While most flowers produce pigments that appear colourful and act as a visual cue to pollinators, some flowers also create microscopic three-dimensional patterns on their petal surfaces. These parallel striations reflect particular wavelengths of light to produce an iridescent optical effect that is not always visible to human eyes, yet visible to bees.

    There is lots of competition for attention from pollinators and – given that 35 percent of the world’s crops rely on animal pollinators – understanding how plants make petal patterns that please pollinators could be significant for directing future research and policies in agriculture, biodiversity and conservation. 

    Research led by Professor Beverley Glover’s team at Cambridge’s Department of Plant Sciences revealed there is more to petal patterning than meets the eye. Previous results indicated that mechanical buckling of the thin, protective cuticle layer on the surface of the young growing petals could trigger the formation of microscopic ridges. These semi-ordered ridges act as diffraction gratings that reflect different wavelengths of light to create a weak iridescent blue-halo effect in the blue-UV spectrum that bumblebees can see. However, why those striations only form in certain flowers or even only on certain parts of the petals was not understood.

    Edwige Moyroud, who started this research in Professor Glover’s lab and is now leading her own research group at the Sainsbury Laboratory, has developed the Australian native hibiscus, Venice mallow (Hibiscus trionum), as a new model species to try to understand how and when these nanostructures develop.

    “Our initial model predicted that how much cells grow and how much cuticle those cells make were key factors controlling the formation of striations,” said Dr Moyroud, “but when we started to test the model using experimental work in Venice mallow we found out that their formation is also highly dependent on cuticle chemistry, which affects how the cuticle responds to the forces that cause buckling. The next question we want to explore is how different chemistries can change the mechanical properties of the cuticle, as a nanostructure-building material. It may be that different chemical compositions result in a cuticle with differing architecture or with different stiffness and hence different ways of reacting to the forces experienced by cells as the petal grows.” 

    This project revealed that there is a combination of processes working together and allowing plants to shape their surfaces. Dr Moyroud added: “Plants are formidable chemists and these results illustrate how they can precisely tune the chemistry of their cuticle to produce different textures across their petals. Patterns formed at the microscopic scale can fulfil a range of functions, from communication with pollinators to defence against herbivores or pathogens. They are striking examples of evolutionary diversification and by combining experiments and computational modelling we are starting to understand a little bit better how plants can fabricate them.”

    The findings will be published on 23 November 2022 in the journal Current Biology.

    “These insights are also useful for biodiversity and conservation work because they help to explain how plants interact with their environment,” said Professor Glover, who is also Director of the Cambridge University Botanic Garden, in which the researchers first noticed the iridescent flowers of Venice mallow.  “For example, species that are closely related but that grow in different geographic regions can have very different petal patterns. Understanding why petal pattering varies and how this might affect the relationship between the plants and their pollinators could help to better inform policies in future management of environmental systems and conservation of biodiversity.” 

     

    Investigating what drives 3D petal patterning

    The researchers took a stepwise approach to the investigations. They first observed petal development and noticed that the cuticle patterns appear when cells elongate, suggesting that growth was important. They then determined whether measuring physical parameters related to growth, such as cell expansion and cuticle thickness, could adequately predict the patterns observed, and found that they couldn’t. They then took a step backwards to try to identify what was missing.

    The properties of a material, whether inorganic or produced by living cells like the cuticle, are likely to depend on the chemical nature of this material. With this in mind, the researchers decided to look at cuticle chemistry, and found that, indeed, this is a controlling factor. To do this, they first used a new method from the chemistry field to analyse the composition of the cuticle at very specific points across the petal. This showed that petal regions with contrasting textures (smooth or striated) also differ in the chemistry of their surface. Comparing with smooth cuticle, they found the striated cuticle has high levels of dihydroxy-palmitic acid and waxes and low levels of phenolic compounds. To test if cuticle chemistry was indeed important, they then pioneered a transgenic approach in Hibiscus to alter cuticle chemistry directly in the plants, using genes similar to those known to control the production of cuticle molecules in a different model plant, Arabidopsis. This showed that cuticle texture can be modified, without changing cell growth, simply by modifying cuticle composition. How can cuticle chemistry control its 3D folding? The researchers think that a change in cuticle chemistry affects the mechanical properties of the cuticle as, even when stretched using a special device, transgenic petals with smooth cuticle remained smooth, unlike those from wild-type plants.

     

    Funding 

    This work was funded by EU Marie Curie Actions, BBSRC, the European Research Council, Herchel Smith Fund and the Gatsby Charitable Foundation. 

     

    Reference

    Edwige Moyroud, Chiara A. Airoldi, Jordan Ferria, Chiara Giorio, Sarah S. Steimer, Paula J. Rudall, Christina J. Prychid, Shannon Halliwell, Joseph F. Walker, Sarah Robinson, Markus Kalberer, and Beverley J. Glover (2022) Cuticle chemistry drives the development of diffraction gratings on the surface of Hibiscus trionum petals. Current Biology

    DOI: 10.1016/j.cub.2022.10.065

    Public URL: https://www.cell.com/current-biology/fulltext/S0960-9822(22)01713-4

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    University of Cambridge

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  • Tracking Explosions with Toughened-Up Tracers

    Tracking Explosions with Toughened-Up Tracers

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    Newswise — What happens in an explosion? Where do the products of that explosion go following the blast? These questions are often difficult to solve. New rugged tracer particles, developed by Pacific Northwest National Laboratory (PNNL) researchers, can provide some answers.

    Beyond explosives, many industries may be interested in tracking particulates through harsh environments—which often include high pressures, high temperatures, and different chemicals.  

    “Lots of chemical tracers exist,” said Lance Hubbard, materials scientist supporting PNNL’s national security research. “The challenge is developing one that can survive harsh environments. It took a few years to convince anyone we could do it.”

    Hubbard and his team, along with fellow PNNL researchers April Carman and Michael Foxe, created a tracer that could not only survive but thrive in extreme conditions. Their work was published in MRS Communications.

    Quantum dots and water-soaked glass

    Organic materials, such as fluorescent dyes, are commonly used as tracers for water leaks and tracking cells in biological experiments. While they work great in those conditions, they aren’t so good for tracing material in explosions. Their problem?

    “They burn,” said Hubbard.

    Instead, Hubbard and his team focused on inorganic materials to develop their rugged tracers—particularly quantum dots. Though they fared much better than organic materials in harsh conditions, the research team still needed to protect the quantum dots from the extreme conditions of a chemical explosion.

    “Finding a way to protect the tracer while still maintaining its luminescent intensity proved to be difficult,” said Carman.

    The tracer’s brightness—or luminescent intensity—can be greatly affected by the local environment. Some protective methods can diminish the brightness, making the tracer more difficult to detect. The team focused on using hydrated silica—“basically water-soaked glass” as Hubbard puts it—to protect the quantum dots and maintain their brightness.

    Though previous silica coating methods significantly decreased tracer luminescence, the coated tracers designed by the PNNL team were almost as bright as the original quantum dots. Further testing showed that the particles could survive for long periods of time through a range of pH conditions.

    “We knew we created something special when we saw our results,” said Hubbard.

    Making tracers tunable and mass-producible

    Special is one thing, but useable on the commercial scale is another. Lucky for the PNNL team, their synthesis method was designed from the get-go to be completely scalable to produce mass quantities—from kilograms to potential tons per day.

    Not only can they make large amounts of the tracer, but they can customize them as well. “We can tune both the tracer’s size and color to any specificity,” said Foxe. “The tracer can be fine-tuned to create a mimic of the mass or material that is being tracked. We can also use a variety of sizes with different colors to visualize how an explosion affects particles of different sizes.”

    The tracers are rugged enough to be deployed in harsh environments to track mass and improve scientists’ understanding of environmental fate and transport. They can function under conditions that are too severe for traditional tracers—like in oil and gas refineries or geothermal plants. With tunable parameters and an easy-to-use system, these tracers have many potential applications for tracking material fate and transport in harsh environments.

    Persistence pays off

    The research has now grown from a small initial investment from the National Nuclear Security Administration (NNSA), Defense Nuclear Nonproliferation Research and Development program to encompassing several related projects.

    “We are glad we could keep pursuing this project despite initial skepticism,” said Carman. “We are also thrilled to see where it leads us next.”

    Additional PNNL authors on this research are Clara Reed, Anjelica Bautista, Maurice Lonsway, Nicolas Uhnak, Ryan Sumner, Trevor Cell, Erin Kinney, Nathaniel Smith, and Caleb Allen. Scientists and engineers from Los Alamos National Laboratory, Lawrence Livermore National Laboratory, Mission Support and Test Services LLC, and Sandia National Laboratories also contributed to the project.

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    About PNNL

    Pacific Northwest National Laboratory draws on its distinguishing strengths in chemistry, Earth sciences, biology and data science to advance scientific knowledge and address challenges in sustainable energy and national security. Founded in 1965, PNNL is operated by Battelle for the Department of Energy’s Office of Science, which is the single largest supporter of basic research in the physical sciences in the United States. DOE’s Office of Science is working to address some of the most pressing challenges of our time. For more information, visit https://energy.gov/science. For more information on PNNL, visit PNNL’s News Center. Follow us on Twitter, Facebook, LinkedIn and Instagram.

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    Pacific Northwest National Laboratory

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  • A Radical New Approach in Synthetic Chemistry

    A Radical New Approach in Synthetic Chemistry

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    Newswise — UPTON, NY—Scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory helped measure how unpaired electrons in atoms at one end of a molecule can drive chemical reactivity on the molecule’s opposite side. As described in a paper recently published in the Journal of the American Chemical Society, this work, done in collaboration with Princeton University, shows how molecules containing these so-called free radicals could be used in a whole new class of reactions.

    “Most reactions involving free radicals take place at the site of the unpaired electron,” explained Brookhaven Lab chemist Matthew Bird, one of the co-corresponding authors on the paper. The Princeton team had become experts in using free radicals for a range of synthetic applications, such as polymer upcycling. But they’ve wondered whether free radicals might influence reactivity on other parts of the molecule as well, by pulling electrons away from those more distant locations.

    “Our measurements show that these radicals can exert powerful ‘electron-withdrawing’ effects that make other parts of the molecule more reactive,” Bird said.

    The Princeton team demonstrated how that long-distance pull can overcome energy barriers and bring together otherwise unreactive molecules, potentially leading to a new approach to organic molecule synthesis.

    Combining capabilities

    The research relied on the combined resources of a Princeton-led DOE Energy Frontier Research Center (EFRC) focused on Bio-Inspired Light Escalated Chemistry (BioLEC). The collaboration brings together leading synthetic chemists with groups having advanced spectroscopic techniques for studying reactions. Its funding was recently renewed for another four years.

    Robert Knowles, who led Princeton’s role in this research, said, “This project is an example of how BioLEC’s combined expertise enabled the team to quantify an important physical property of these radical species, that in turn allowed us to design the resulting synthetic methodology.”

    The Brookhaven team’s major contribution is a technique called pulse radiolysis—available only at Brookhaven and one other location in the U.S.

    “We use the Laser Electron Accelerator Facility (LEAF)—part of the Accelerator Center for Energy Research (ACER) in Brookhaven’s Chemistry Division—to generate intense high-energy electron pulses,” Bird explained. “These pulses allow us to add or subtract electrons from molecules to make reactive species that might be difficult to make using other techniques, including short-lived reaction intermediates. With this technique, we can step into one part of a reaction and monitor what happens.”

    For the current study, the team used pulse radiolysis to generate molecules with oxygen-centered radicals, and then measured the “electron-withdrawing” effects on the other side of the molecule. They measured the electron pull by tracking how much the oxygen at the opposite side attracts protons, positively charged ions sloshing around in solution. The stronger the pull from the radical, the more acidic the solution has to be for protons to bind to the molecule, Bird explained.

    The Brookhaven scientists found the acidity had to be high to enable proton capture, meaning the oxygen radical was a very strong electron withdrawing group. That was good news for the Princeton team. They then demonstrated that it’s possible to exploit the “electron-withdrawing” effect of oxygen radicals by making parts of molecules that are generally inert more chemically reactive.

    “The oxygen radical induces a transient ‘polarity reversal’ within the molecule—causing electrons that normally want to remain on that distant side to move toward the radical to make the ‘far’ side more reactive,” Bird explained.

    These findings enabled a novel substitution reaction on phenol based starting materials to make more complex phenol products.

    “This is a great example of how our technique of pulse radiolysis can be applied to cutting-edge science problems,” said Bird. “We were delighted to host an excellent graduate student, Nick Shin, from the Knowles group for this collaboration. We look forward to more collaborative projects in this second phase of BioLEC and seeing what new problems we can explore using pulse radiolysis.”

    Brookhaven Lab’s role in this work and the EFRC at Princeton were funded by the DOE Office of Science (BES). Princeton received additional funding for the synthesis work from the National Institutes of Health.

    Brookhaven National Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit science.energy.gov.

    Follow @BrookhavenLab on Twitter or find us on Facebook.

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  • Looking at oxygen storage dynamics in three-way catalysts

    Looking at oxygen storage dynamics in three-way catalysts

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    Newswise — In light of vehicular pollutants contributing to decreasing air quality, governments across the globe are posing stricter emission regulations for automobiles. This calls for the development of more efficient exhaust gas after-treatment systems (i.e., systems to “clean” exhaust gas before it is released into the atmosphere). The most common mode for treating exhaust emissions of gasoline-fueled internal combustion engines are three-way catalysts (TWCs) or catalytic converters. TWCs often comprise active metals such as platinum (Pt) and palladium (Pd) nanoparticles and oxygen storage materials with a high specific surface area, such as a solid solution of CeO2-ZrO2(CZ). These components can catalyze multiple oxidation and reduction reactions that can convert harmful exhaust from vehicular engines to harmless gases.

    The durability, precision, and performance of a TWC is dependent on factors like the oxygen stored or removed from the bulk and surface of the oxygen storage materials. So, clearly understanding the oxygen transport and dynamics of the storage material is necessary to improve its efficiency. Unfortunately, there is a lack of techniques that can enable direct tracking of the oxygen storage process in TWCs.

    In a recent breakthrough published in Chemical Engineering Journal, however, a team of researchers led by Assistant Professor Tsuyoshi Nagasawa of Tokyo Institute of Technology (Tokyo Tech) presented a solution to the problem. The team developed a novel technique for direct visualization of the oxygen storage process in Pd/CZ TWCs using the isotope quenching technique. Prof Nagasawa explains: “It is difficult to get clarity on the dynamic interactions—such as oxygen adsorption/desorption and surface/bulk diffusion—occuring on TWC surfaces, because they can only be estimated indirectly from the valence change of cerium in CZ, or the oxidation state of the noble metal. However, our method surpasses these problems by incorporating isotope labeling with reaction quenching, which allows us to investigate the oxygen storage processes by tracking the 18O isotope involved in these interactions.”

    How was this isotope quenching technique carried out? The team prepared a model TWC consisting of a precious metal, Pd, and a dense CZ substrate, stored 18O2 in it at 600 °C, and then quenched the catalyst using two helium gas nozzles covered in a water cooling jacket. They then used high-resolution secondary-ion mass spectrometry to analyze the 18O distribution on the surface and bulk of Pd/CZ.

    The results indicated that Pd improves the diffusion depth of 18O into CZ bulk, as well as its surface concentration. It further revealed that 18O was preferentially adsorbed at the Pd/CZ interface as compared to the Pd center, where its concentration was lower. Density functional theory calculations also agreed with these observations.

    Finally, the team calculated the local oxygen release/storage rates by comparing 18O distribution and an oxygen release/storage simulation using a diffusion equation. They found that the local rates were comparable and consistent with conventional oxygen storage capacity measurements.

    This new visualization process provides useful insights into the oxygen storage and release mechanisms in metal/oxygen materials systems and can be used to further investigate and improve the performance and efficiency of TWCs used for automobile exhaust treatment. “The volatile organic compounds and oxides of nitrogen and carbon commonly produced by combustion engines, if released without treatment, can not only cause breathing-related health issues but can also indirectly impact the acceleration of global warming. With our study, we wanted to contribute towards the world’s mission to achieve better emission practices,” concludes Prof. Nagasawa.

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  • Toxins force construction of ‘roads to nowhere’

    Toxins force construction of ‘roads to nowhere’

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    Newswise — COLUMBUS, Ohio – Toxins released by a type of bacteria that cause diarrheal disease hijack cell processes and force important proteins to assemble into “roads to nowhere,” redirecting the proteins away from other jobs that are key to proper cell function, a new study has found. 

    The affected proteins are known as actins, which are highly abundant and have multiple roles that include helping every cell unite its contents, maintain its shape, divide and migrate. Actins assemble into thread-like filaments to do certain work inside cells. 

    Researchers found that two toxins produced by the Vibrio genus of bacteria cause actins to start joining together into these filaments – which could be thought of as cellular highways on which cargo is delivered – at the wrong location inside cells, and headed in the wrong direction. 

    “Growing in the wrong direction is a totally new function that was not previously known and was not thought to be possible for actin filaments inside the cell,” said senior author Dmitri Kudryashov, associate professor of chemistry and biochemistry at The Ohio State University. “A large fraction of actin in the cell is consumed in formation of the ‘highways’ where they are not needed, so the cell resources are wasted and cannot be used to satisfy the cell’s basic needs.” 

    The research is published today (Nov. 18, 2022) in the journal Science Advances. 

    These disruptive toxins are called VopF and VopL, and are produced by two strains of Vibrio bacteria living in seawater: V. cholerae and V. parahaemolyticus, both of which can contaminate oysters and other shellfish that, when eaten raw, make people sick. 

    In this study, the research team zeroed in on describing the unexpected cellular activities rather than any further implications, such as how the hijacking relates to bacterial infection. 

    “We are looking at the interference at the molecular level – we have not focused here on how this cell function might affect humans,” said first and co-corresponding author Elena Kudryashova, a research scientist in chemistry and biochemistry at Ohio State. 

    “From a practical standpoint, this tells us more about these pathogens, and knowing your enemy helps you fight your enemy,” she said. “But finding something that we didn’t know was possible – for actin to behave in such a way inside the cell – raises new questions about whether this function might actually be needed, or could come about in some other way.” 

    Until now, actins have been known to assemble each filament in one way, originating from what is known as its pointed end and directed toward what is called the barbed end of the structure. Because they are limited in number, the actins disassemble as needed from the pointed end and are recycled to maintain directional activity toward the barbed end – and then these actin filaments perform functions, such as cell migration, contraction or division, as dictated by what the cell commands. 

    When the VopF and VopL toxins enter a cell, however, they attract actin molecules to start a new filament and cause the filaments to start assembling in this spot, which leads them to elongate in the direction of the pointed end – a reversal of their usual elongation direction.

    “The toxins start making these actin filament highways in the wrong place, building something that is useless for the cell, and the cell doesn’t know how to deal with it,” Kudryashov said. 

    This actin interference was observed using imaging of live cells containing individual toxin molecules. Though they don’t yet know all the consequences of this hijacking activity, the researchers said the results could include seepage of nutrients through damaged intestinal walls – which would provide food for the infectious bacteria waiting outside. 

    “Killing cells is not always necessary – disrupting cells’ barrier function can also be beneficial to pathogens,” Kudryashova said. 

    And that’s why the scientists want to learn more – whether other molecules can force actins to assemble “roads to nowhere,” and whether that strange filament formation might even be a beneficial mechanism under a different set of circumstances.

    “It’s quite possible that our own cells are doing this on some occasion, but we don’t know because actin has so many functions and not all of them are yet well understood,” Kudryashov said. 

    The Ohio State team collaborated with co-authors Ankita, Heidi Ulrichs and Shashank Shekhar of Emory University.

    This work was supported by grants from the National Institutes of Health.

     

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  • FRIB Experiment Pushes Elements to the Limit

    FRIB Experiment Pushes Elements to the Limit

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    Newswise — A new study led by the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) has measured how long it takes for several kinds of exotic nuclei to decay. The paper, published today in Physical Review Letters, marks the first experimental result from the Facility for Rare Isotope Beams (FRIB), a DOE Office of Science user facility operated by Michigan State University.

    Scientists used the one-of-a-kind facility to better understand nuclei, the collection of protons and neutrons found at the heart of atoms. Understanding these basic building blocks allows scientists to refine their best models and has applications in medicine, national security, and industry.

    “The breadth of the facility and the programs that are being pursued are really exciting to watch,” said Heather Crawford, a physicist at Berkeley Lab and lead spokesperson for the first FRIB experiment. “Research is going to be coming out in different areas that will impact things we haven’t even thought of yet. There’s so much discovery potential.”

    The first experiment is just a small taste of what’s to come at the facility, which will become 400 times more powerful over the coming years. “It’s going to be really exciting – mind-blowing, honestly,” Crawford said.

    More than 50 participants from ten universities and national laboratories were involved in the first experiment. The study looked at isotopes of several elements. Isotopes are variations of a particular element; they have the same number of protons but can have different numbers of neutrons.

    Researchers focused on unstable isotopes near the “drip-line,” the spot where neutrons can no longer bind to a nucleus. Instead, any additional neutrons drip off, like water from a saturated kitchen sponge.

    Researchers smashed a beam of stable calcium-48 nuclei traveling at about 60% of the speed of light into a beryllium target. The calcium fragmented, producing a slew of isotopes that were separated, individually identified, and delivered to a sensitive detector that measured how long they took to decay. The result? The first reported measurements of half-lives for five exotic, neutron-laden isotopes of phosphorus, silicon, aluminum, and magnesium.

    Half-life measurements (perhaps best known from applications in carbon dating) are one of the first things researchers can observe about these short-lived particles. The fundamental information about nuclei at the limits of their existence provides a useful test for different models of the atomic world.

    “This is a basic science question, but it links to the bigger picture for the field,” Crawford said. “Our aim is to describe not only these nuclei, but all kinds of nuclei. These models help us fill in the gaps, which helps us more reliably predict things we haven’t been able to measure yet.”

    More complete theories help advance research in areas such as astrophysics and nuclear physics – for example, understanding how elements form in exploding stars or how processes unfold in nuclear reactors.

    Crawford and the team plan to repeat the half-life experiment again next year, taking advantage of additional beam intensity that will increase the number of isotopes produced, including rare isotopes near the neutron drip-line. In the meantime, other groups will take advantage of the facility’s many beamlines and instruments.

    “Bringing the facility online was a big effort by a lot of people, and something the community has been looking forward to for a long time,” Crawford said. “I’m excited I am young enough to keep taking advantage of it for the next several decades.”

    Multiple institutions collaborated on the first experiment, with researchers from Argonne National Laboratory (ANL), Berkeley Lab, Brookhaven National Laboratory, Florida State University, FRIB, Lawrence Livermore National Laboratory, Louisiana State University, Los Alamos National Laboratory, Mississippi State University, Oak Ridge National Laboratory (ORNL), and the University of Tennessee Knoxville (UTK).

    Scientists from ORNL, UTK, ANL and FRIB led the collaboration to provide the instruments used in the FRIB Decay Station initiator, the sensitive detector system that measured the isotopes.

    Michigan State University (MSU) operates the Facility for Rare Isotope Beams (FRIB) as a user facility for the U.S. Department of Energy Office of Science (DOE-SC), supporting the mission of the DOE-SC Office of Nuclear Physics. Hosting what is designed to be the most powerful heavy-ion accelerator, FRIB enables scientists to make discoveries about the properties of rare isotopes in order to better understand the physics of nuclei, nuclear astrophysics, fundamental interactions, and applications for society, including in medicine, homeland security, and industry.

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    Founded in 1931 on the belief that the biggest scientific challenges are best addressed by teams, Lawrence Berkeley National Laboratory and its scientists have been recognized with 16 Nobel Prizes. Today, Berkeley Lab researchers develop sustainable energy and environmental solutions, create useful new materials, advance the frontiers of computing, and probe the mysteries of life, matter, and the universe. Scientists from around the world rely on the Lab’s facilities for their own discovery science. Berkeley Lab is a multiprogram national laboratory, managed by the University of California for the U.S. Department of Energy’s Office of Science.

    DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science.

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  • Growing pure nanotubes is a stretch, but possible

    Growing pure nanotubes is a stretch, but possible

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    Newswise — HOUSTON – (Nov. 9, 2022) – Like a giraffe stretching for leaves on a tall tree, making carbon nanotubes reach for food as they grow may lead to a long-sought breakthrough.

    Materials theorists Boris Yakobson and Ksenia Bets at Rice University’s George R. Brown School of Engineering show how putting constraints on growing nanotubes could facilitate a “holy grail” of growing batches with a single desired chirality.

    Their paper in Science Advances describes a strategy by which constraining the carbon feedstock in a furnace would help control the “kite” growth of nanotubes. In this method, the nanotube begins to form at the metal catalyst on a substrate, but lifts the catalyst as it grows, resembling a kite on a string.

    Carbon nanotube walls are basically graphene, its hexagonal lattice of atoms rolled into a tube. Chirality refers to how the hexagons are angled within the lattice, between 0 and 30 degrees. That determines whether the nanotubes are metallic or semiconductors. The ability to grow long nanotubes in a single chirality could, for instance, enable the manufacture of highly conductive nanotube fibers or semiconductor channels of transistors.

    Normally, nanotubes grow in random fashion with single and multiple walls and various chiralities. That’s fine for some applications, but many need “purified” batches that require centrifugation or other costly strategies to separate the nanotubes.

    The researchers suggested hot carbon feedstock gas fed through moving nozzles could effectively lead nanotubes to grow for as long as the catalyst remains active. Because tubes with different chiralities grow at different speeds, they could then be separated by length, and slower-growing types could be completely eliminated.

    One additional step that involves etching away some of the nanotubes could then allow specific chiralities to be harvested, they determined.

    The lab’s work to define the mechanisms of nanotube growth led them to think about whether the speed of growth as a function of individual tubes’ chirality could be useful. The angle of “kinks” in the growing nanotubes’ edges determines how energetically amenable they are to adding new carbon atoms.

    “The catalyst particles are moving as the nanotubes grow, and that’s principally important,” said lead author Bets, a researcher in Yakobson’s group. “If your feedstock keeps moving away, you get a moving window where you’re feeding some tubes and not the others.”

    The paper’s reference to Lamarck giraffes — a 19th-century theory of how they evolved such long necks — isn’t entirely out of left field, Bets said.  

    “It works as a metaphor because you move your ‘leaves’ away and the tubes that can reach it continue growing fast, and those that cannot just die out,” she said. “Eventually, all the nanotubes that are just a tiny bit slow will ‘die.’”

    Speed is only part of the strategy. In fact, they suggest nanotubes that are a little slower should be the target to assure a harvest of single chiralities.

    Because nanotubes of different chiralities grow at their own rates, a batch would likely exhibit tiers. Chemically etching the longest nanotubes would degrade them, preserving the next level of tubes. Restoring the feedstock could then allow the second-tier nanotubes to continue growing until they are ready to be culled, Bets said.

    “There are three or four laboratory studies that show nanotube growth can be reversed, and we also know it can be restarted after etching,” she said. “So all the parts of our idea already exist, even if some of them are tricky. Close to equilibrium, you will have the same proportionality between growth and etching speeds for the same tubes. If it’s all nice and clean, then you can absolutely, precisely pick the tubes you target.”

    The Yakobson lab won’t make them, as it focuses on theory, not experimentation. But other labs have turned past Rice theories into products like boron buckyballs.

    “I’m pretty sure every single one of our reviewers were experimentalists, and they didn’t see any contradictions to it working,” Bets said. “Their only complaint, of course, was that they would like experimental results right now, but that’s not what we do.”

    She hopes more than a few labs will pick up the challenge. “In terms of science, it’s usually more beneficial to give ideas to the crowd,” Bets said. “That way, those who have interest can do it in 100 different variations and see which one works. One guy trying it might take 100 years.”

    Yakobson added, “We don’t want to be that ‘guy.’ We don’t have that much time.”

    Yakobson is the Karl F. Hasselmann Professor of Engineering and a professor of materials science and nanoengineering and of chemistry.

    The National Science Foundation (1605848) and the Robert Welch Foundation (C-1490) supported the research.

    -30-

     

    Related stories:

    Oddball edge wins nanotube faceoff – July 29, 2019
    https://news2.rice.edu/2019/07/29/oddball-edge-wins-nanotube-faceoff-2/

    Two-faced edge makes nanotubes obey – July 26, 2018 https://news2.rice.edu/2018/07/26/two-faced-edge-makes-nanotubes-obey-2/

    Graphene grows stronger against the wind – March 12, 2018 https://news2.rice.edu/2018/03/12/graphene-grows-stronger-against-the-wind-2/

     

    Links:

    Dislocation theory of chirality-controlled nanotube growth: https://www.pnas.org/doi/10.1073/pnas.0811946106

    Yakobson Research Group: biygroup.blogs.rice.edu

    Department of Materials Science and NanoEngineering: msne.rice.edu

    George R. Brown School of Engineering: engineering.rice.edu

    This release can be found online at https://news.rice.edu/news/2022/growing-pure-nanotubes-stretch-possible.

    Follow Rice News and Media Relations via Twitter @RiceUNews.

    Located on a 300-acre forested campus in Houston, Rice University is consistently ranked among the nation’s top 20 universities by U.S. News & World Report. Rice has highly respected schools of Architecture, Business, Continuing Studies, Engineering, Humanities, Music, Natural Sciences and Social Sciences and is home to the Baker Institute for Public Policy. With 4,240 undergraduates and 3,972 graduate students, Rice’s undergraduate student-to-faculty ratio is just under 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice is ranked No. 1 for lots of race/class interaction and No. 1 for quality of life by the Princeton Review. Rice is also rated as a best value among private universities by Kiplinger’s Personal Finance.

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  • Fertilisers Limit Pollination by Changing How Bumblebees Sense Flowers

    Fertilisers Limit Pollination by Changing How Bumblebees Sense Flowers

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    Newswise — Pollinators are less likely to land on flowers sprayed with fertilisers or pesticides as they can detect electric field changes around the flower, researchers at the University of Bristol have found.

    The study, published in PNAS Nexus today, shows that chemical sprays alter the electric field around flowers for up to 25 minutes after exposure. This impact lasts substantially longer than natural fluctuations, such as those caused by wind, and causes a reduction in bee feeding effort in nature.

    Dr Ellard Hunting of Bristol’s School of Biological Sciences and his team noted that fertilisers did not affect vision and smell, and set out to mimic the electrical changes caused by fertilisers and pesticides in the field by electrically manipulating flowers. This showed that bumblebees were able to detect and discriminate against the small and dynamic electric field alterations that are caused by the chemicals.

    Dr. Ellard Hunting said: “We know that chemicals are toxic, but we know little about how they affect the immediate interaction between plants and pollinators.

    “Flowers have a range of cues that attract bees to promote feeding and pollination. For instance, bees use cues like flower odour and colour, but they also use electric fields to identify plants.

    “A big issue is thus – agrochemical application can distort floral cues and modify behaviour in pollinators like bees.”

    Furthermore, various other airborne particles such as nanoparticles, exhaust gasses, nano-plastics, and viral particles may have similar impacts, affecting a wide array of organisms that use the electric fields that are virtually everywhere in the environment.

    Co-author, Bristol’s Sam England, explained: “What makes this study important is that it’s the first known example of anthropogenic ‘noise’  interfering with a terrestrial animal’s electrical sense.

    ”It’s much like motorboat noise that hinders the ability of fish to detect their predators, or artificial light at night that confuses moths; the fertilisers are a source of noise to bees trying to detect floral electrical cues.

    “This widens our understanding of the multifaceted ways in which human activity is negatively impacting the natural world, which can seem quite depressing, but it will hopefully allow is to introduce or invent solutions to prevent the adverse effects that these chemicals may be having on bees.”

    Dr Ellard Hunting added: “The fact that fertilisers affect pollinator behavior by interfering with the way an organism perceives its physical environment offers a new perspective on how human-made chemicals disturb the natural environment.”

    The project was funded by the European Research Council and the Swiss National Science Foundation.

    Paper:

     

    ‘Synthetic fertilizers alter floral biophysical cues and bumblebee foraging behaviour’ by E Hunting, S England et al in PNAS Nexus.

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  • New quantum phase discovered for developing hybrid materials

    New quantum phase discovered for developing hybrid materials

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    Newswise — Osaka, Japan – If you have ever watched water freeze to ice, you have witnessed what physicists call a “phase transition.” Osaka Metropolitan University scientists have discovered an unprecedented phase transition during which crystals achieve amorphous characteristics while retaining their crystalline properties. Their findings contribute to developing hybrid materials for use in harsh environments, such as outer space. The results were published in Physical Review B.

    A typical phase transition exhibited by crystalline solids involves a change in the crystal structure. Such structural phase transitions usually occur at finite temperatures. However, controlling the chemical composition of the crystal can lower the transition temperature to absolute zero (−273°C). The transition point at absolute zero is called the structural quantum critical point.

    In the dielectric compound Ba1-xSrxAl2O4, the structural phase transition is driven by an acoustic soft mode, the atomic vibration pattern of which is similar to that of sound waves. The compound comprises an AlO4 tetrahedral network and Ba/Sr atoms. The research team led by Associate Professor Yui Ishii from the Graduate School of Engineering at Osaka Metropolitan University has discovered that a highly disordered atomic arrangement is formed in the AlO4 network at chemical compositions near the structural quantum critical point, resulting in both characteristics of crystalline and amorphous materials.

    Ba1-xSrxAl2O4 is a crystalline solid. However, the researchers found that at higher Sr concentrations than the structural quantum critical point, Ba1-xSrxAl2O4 exhibits the thermal characteristic of amorphous materials, i.e., low thermal conductivity comparable to that of glass materials (e.g., silica glass). They observed that a part of the atomic structure loses periodicity because of the incoherently stopped acoustic soft mode. As a result, a combination of a glassy Al-O network and a periodic Ba arrangement is realized.

    This hybrid state, which the research team was the first to discover, can be created simply by mixing raw materials uniformly and heating them.

    Professor Ishii concluded, “In principle, the phenomenon revealed in this research can occur in materials exhibiting acoustic soft modes. Applying this technique to various materials will possibly help us create hybrid materials that combine the physical properties of crystals, such as optical properties and electrical conductivity, with the low thermal conductivity of amorphous materials. In addition, the high heat resistance of crystals can be utilized to develop insulation materials that can be used in harsh environments, such as outer space.”

     

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    About OMU

    Osaka Metropolitan University is a new public university established in April 2022, formed by merger between Osaka City University and Osaka Prefecture University. For more research news, visit https://www.upc-osaka.ac.jp/new-univ/en-research/research/ or follow @OsakaMetUniv_en and #OMUScience.

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  • New Tool for Estimating People’s Total Exposure to Potentially Harmful Chemicals Is Developed

    New Tool for Estimating People’s Total Exposure to Potentially Harmful Chemicals Is Developed

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    Newswise — New York, NY (November 2, 2022) – A novel metric that estimates our “burden,” or cumulative exposure, to a family of thousands of synthetic chemicals that we encounter in everyday life with potentially adverse health impacts, has been created by a team of researchers at Mount Sinai.

    In a paper published in Environmental Health Perspectives, the team reported that its sophisticated tool could have distinct advantages for epidemiologists and researchers who routinely measure exposure levels to this class of chemicals, known as PFAS (per- and polyfluoroalkyl substances), which have been associated with high cholesterol, liver damage, thyroid disease, and hormone disorders.

    “There are few existing methods to quantify total exposure burden of individuals to mixtures of PFAS chemicals that are found in our everyday lives,” says lead author Shelley Liu, PhD, Assistant Professor in the Center for Biostatistics, Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai. “For the first time we’ve developed a PFAS burden calculator that takes into account patterns of exposure to many chemicals within the PFAS family, and not just individual chemical concentrations which current methods are focused on. As a result, this robust tool could be extremely useful for biomonitoring by regulatory agencies, and for disease and health risk assessment.”

    PFAS is a class of more than 5,000 chemicals whose fluorine-carbon bond gives them the ability to repel oil and water. That construct has made them an integral part of a growing number of industrial applications and consumer products in recent decades, such as stain and water repellents, Teflon nonstick pans, paints, cleaners, and food packaging. Moreover, PFAS chemicals do not disintegrate in the environment or in our bodies. Instead, they accumulate in our surroundings and in our blood, kidneys, and liver, as underscored by a Centers for Disease Control and Prevention study in 2007 that found PFAS could be detected in the blood of 98 percent of the U.S. population.

    Mount Sinai researchers used national biomonitoring data from the National Health and Nutrition Examination Survey to develop their exposure burden score using item response theory. Item response theory was developed in the educational testing literature to score standardized tests, and Mount Sinai researchers are the first to use it in environmental epidemiology to develop an exposure burden score, highlighted by this transdisciplinary investigation. Specifically, they used serum concentrations from eight common PFAS chemicals taken from adults and children. By combining a participant’s core biomarker concentrations with their much broader “exposure pattern,” that is, their relative exposure to other PFAS biomarkers within the entire chemical class, researchers were able to estimate a cumulative or summary PFAS exposure burden. This statistical methodology can be accessed by other researchers and epidemiologists by simply plugging their data sets into the PFAS burden calculator, which is available online.

    The benefits are significant. “We found our method enables comparisons of exposure burden to chemical mixtures across studies even if they do not measure the same set of chemicals, which supports harmonization across studies and consortia,” explains Dr. Liu, whose research is heavily focused on environmental health through latent variable modeling and longitudinal data analysis. Moreover, the calculator offers a straightforward way to include exposure biomarkers with low detection frequencies, and to reduce exposure measurement errors by considering both a participant’s concentrations and their exposure patterns to estimate exposure burden to chemical mixtures.

    “By capturing individual biomarker variability, we’re essentially holding the exposure metric constant so it can be used for a variety of applications,” says Dr. Liu. “These could include, for example, looking across populations to determine if there are differences in exposure burden across racial/ethnic or socioeconomic strata, or if exposure burdens are the same between people in the United States or Canada. Or looking across physiological systems and health outcomes—such as cardiometabolic, hormonal, and immune—to see which are most perturbed by exposure to PFAS chemicals. This range of applications takes us well beyond anything currently available to the field of population health.” 

    Other co-authors in the study were from the Johns Hopkins Bloomberg School of Public Health, the Department of Psychology at Fordham University, and the Stroud Center at Columbia University. Dr. Liu’s research is supported by grants from the National Institute of Child Health and Human Development (K25HD104918) and National Institute of Environmental Health Sciences (R03ES033374).

     

    About the Mount Sinai Health System

    Mount Sinai Health System is one of the largest academic medical systems in the New York metro area, with more than 43,000 employees working across eight hospitals, over 400 outpatient practices, nearly 300 labs, a school of nursing, and a leading school of medicine and graduate education. Mount Sinai advances health for all people, everywhere, by taking on the most complex health care challenges of our time — discovering and applying new scientific learning and knowledge; developing safer, more effective treatments; educating the next generation of medical leaders and innovators; and supporting local communities by delivering high-quality care to all who need it.

    Through the integration of its hospitals, labs, and schools, Mount Sinai offers comprehensive health care solutions from birth through geriatrics, leveraging innovative approaches such as artificial intelligence and informatics while keeping patients’ medical and emotional needs at the center of all treatment. The Health System includes approximately 7,300 primary and specialty care physicians; 13 joint-venture outpatient surgery centers throughout the five boroughs of New York City, Westchester, Long Island, and Florida; and more than 30 affiliated community health centers. We are consistently ranked by U.S. News & World Report‘s Best Hospitals, receiving high “Honor Roll” status, and are highly ranked: No. 1 in Geriatrics and top 20 in Cardiology/Heart Surgery, Diabetes/Endocrinology, Gastroenterology/GI Surgery, Neurology/Neurosurgery, Orthopedics, Pulmonology/Lung Surgery, Rehabilitation, and Urology. New York Eye and Ear Infirmary of Mount Sinai is ranked No. 12 in Ophthalmology. U.S. News & World Report’s “Best Children’s Hospitals” ranks Mount Sinai Kravis Children’s Hospital among the country’s best in several pediatric specialties. The Icahn School of Medicine at Mount Sinai is one of three medical schools that have earned distinction by multiple indicators: It is consistently ranked in the top 20 by U.S. News & World Report‘s “Best Medical Schools,” aligned with a U.S. News & World Report “Honor Roll” Hospital, and top 20 in the nation for National Institutes of Health funding and top 5 in the nation for numerous basic and clinical research areas. Newsweek’s “The World’s Best Smart Hospitals” ranks The Mount Sinai Hospital as No. 1 in New York and in the top five globally, and Mount Sinai Morningside in the top 20 globally.

    For more information, visit https://www.mountsinai.org or find Mount Sinai on Facebook, Twitter and YouTube.

     

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    Mount Sinai Health System

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  • Building with Nanoparticles, From the Bottom Up

    Building with Nanoparticles, From the Bottom Up

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    Newswise — Researchers at MIT have developed a technique for precisely controlling the arrangement and placement of nanoparticles on a material, like the silicon used for computer chips, in a way that does not damage or contaminate the surface of the material.

    The technique, which combines chemistry and directed assembly processes with conventional fabrication techniques, enables the efficient formation of high-resolution, nanoscale features integrated with nanoparticles for devices like sensors, lasers, and LEDs, which could boost their performance.

    Transistors and other nanoscale devices are typically fabricated from the top down — materials are etched away to reach the desired arrangement of nanostructures. But creating the smallest nanostructures, which can enable the highest performance and new functionalities, requires expensive equipment and remains difficult to do at scale and with the desired resolution.

    A more precise way to assemble nanoscale devices is from the bottom up. In one scheme, engineers have used chemistry to “grow” nanoparticles in solution, drop that solution onto a template, arrange the nanoparticles, and then transfer them to a surface. However, this technique also involves steep challenges. First, thousands of nanoparticles must be arranged on the template efficiently. And transferring them to a surface typically requires a chemical glue, large pressure, or high temperatures, which could damage the surfaces and the resulting device.

    The MIT researchers developed a new approach to overcome these limitations. They used the powerful forces that exist at the nanoscale to efficiently arrange particles in a desired pattern and then transfer them to a surface without any chemicals or high pressures, and at lower temperatures. Because the surface material remains pristine, these nanoscale structures can be incorporated into components for electronic and optical devices, where even minuscule imperfections can hamper performance.

    “This approach allows you, through engineering of forces, to place the nanoparticles, despite their very small size, in deterministic arrangements with single-particle resolution and on diverse surfaces, to create libraries of nanoscale building blocks that can have very unique properties, whether it is their light-matter interactions, electronic properties, mechanical performance, etc.,” says Farnaz Niroui, the EE Landsman Career Development Assistant Professor of Electrical Engineering and Computer Science (EECS) at MIT, a member of the MIT Research Laboratory of Electronics, and senior author on a new paper describing the work. “By integrating these building blocks with other nanostructures and materials we can then achieve devices with unique functionalities that would not be readily feasible to make if we were to use the conventional top-down fabrication strategies alone.”

    The research is published in Science Advances. Niroui’s co-authors are lead author Weikun “Spencer” Zhu, a graduate student in the Department of Chemical Engineering, as well as EECS graduate students Peter F. Satterthwaite, Patricia Jastrzebska-Perfect, and Roberto Brenes.

    Use the forces

    To begin their fabrication method, known as nanoparticle contact printing, the researchers use chemistry to create nanoparticles with a defined size and shape in a solution. To the naked eye, this looks like a vial of colored liquid, but zooming in with an electron microscope would reveal millions of cubes, each just 50 nanometers in size. (A human hair is about 80,000 nanometers wide.)

    The researchers then make a template in the form of a flexible surface covered with nanoparticle-sized guides, or traps, that are arranged in the shape they want the nanoparticles to take. After adding a drop of nanoparticle solution to the template, they use two nanoscale forces to move the particles into the right position. The nanoparticles are then transferred onto arbitrary surfaces.

    At the nanoscale, different forces become dominant (just like gravity is a dominant force at the macroscale). Capillary forces are dominant when the nanoparticles are in liquid and van der Waals forces are dominant at the interface between the nanoparticles and the solid surface they are in contact with. When the researchers add a drop of liquid and drag it across the template, capillary forces move the nanoparticles into the desired trap, placing them precisely in the right spot. Once the liquid dries, van der Waals forces hold those nanoparticles in position.

    “These forces are ubiquitous and can often be detrimental when it comes to the fabrication of nanoscale objects as they can cause the collapse of the structures. But we are able to come up with ways to control these forces very precisely to use them to control how things are manipulated at the nanoscale,” says Zhu.

    They design the template guides to be the right size and shape, and in the precisely proper arrangement so the forces work together to arrange the particles. The nanoparticles are then printed onto surfaces without a need for any solvents, surface treatments, or high temperatures. This keeps the surfaces pristine and properties intact while allowing yields of more than 95 percent. To promote this transfer, the surface forces need to be engineered so that the van der Waals forces are strong enough to consistently promote particles to release from the template and attach to the receiving surface when placed in contact.

    Unique shapes, diverse materials, scalable processing

    The team used this technique to arrange nanoparticles into arbitrary shapes, such as letters of the alphabet, and then transferred them to silicon with very high position accuracy. The method also works with nanoparticles that have other shapes, such as spheres, and with diverse material types. And it can transfer nanoparticles effectively onto different surfaces, like gold or even flexible substrates for next-generation electrical and optical structures and devices.

    Their approach is also scalable, so it can be extended to be used toward fabrication of real-world devices.

    Niroui and her colleagues are now working to leverage this approach to create even more complex structures and integrate it with other nanoscale materials to develop new types of electronic and optical devices.

    This work was supported, in part, by the National Science Foundation (NSF) and the NSF Graduate Research Fellowship Program.

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    Massachusetts Institute of Technology (MIT)

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  • Both Types of THC Get You High–So Why Is Only One Illegal?

    Both Types of THC Get You High–So Why Is Only One Illegal?

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    Newswise — One is an illegal drug found in marijuana while the other is marketed as a safe herbal alternative. But the claimed differences between them aren’t backed by science, a group of UConn researchers report on Nov. 1 in Drug and Alcohol Dependence.

    Tetrahydrocannabinol, or THC, is the psychoactive compound produced by cannabis plants. The federal government lists Δ9 -THC (pronounced delta-9-THC) on the Schedule 1 list of dangerous drugs with no accepted medical use. But other versions of THC that differ only by the location of a double bond, such as Δ8-THC, remain quietly quasi-legal on the federal level.

    The legality differences between the various versions of THC are causing conflict between the hemp and cannabis industries. There is also potential for harm to consumers. Although Δ8-THC is viewed as an herbal extract of hemp, many manufacturers use solvents and chemical processes that can leave harmful residues in the product, and there are no standards for purity or safety. Because there are no limits, some products contain ridiculously high levels of ∆8 and other THC variants that could potentially cause harm due to the sheer dosage. And states do not agree on its safety or legality. Some states, such as Connecticut, have made Δ8-THC as controlled as Δ9-THC, while in others it remains legal. Cannabis producers allege the distinction is giving rise to unfair competition between the hemp and marijuana markets.

    If regulating Δ9-THC as an illegal drug is based on the fact that it has physical and psychoactive effects, then the first step to rational regulation of Δ8-THC would look at whether it, too, has those effects. And people who have experience with both say it does; most agree the effects of Δ8 are similar to Δ9.

    UConn School of Nursing professor and Center for Advancement in Managing Pain director Steve Kinsey, graduate student Olivia Vanegas, and their colleagues in UConn Chemistry and local startup 3BC Inc decided to test that in mice. Research done in Japan in the 1980s had shown that Δ8-THC produced the same effects in mice as Δ9-THC. Kinsey and Vanegas reproduced that work and found it to be true: the mice given Δ8 became lethargic, their body temperature dropped, and they became cataleptic, meaning the researchers could put the mice in unusual positions and they’d stay like that for several seconds, which is common in THC-treated mice, but not normal mice.

    Then the researchers took it a step farther, blocking the mice’s THC receptors. Blocked mice had no reaction to Δ8-THC, making it clear that Δ8 interacts with the same receptors as Δ9-THC.

    Then the researchers took a group of mice and gave them Δ8-THC twice a day for five days. Over time, the mice became desensitized to it. And when they were then given the THC blocker, the mice acted like they were in withdrawal.

    Finally collaborators at RTI International ran an experiment “asking” the mice how the drug felt. First they trained the mice to go to a specific spot for a reward if they were dosed with Δ9-THC. After the training, the mice were dosed with Δ8-THC. Unsurprisingly, they went to the same reward spot as when they were dosed with Δ9.

    “So they’re telling us the same thing people buying the stuff in gas stations tell us: Δ8 feels like THC,” Kinsey says.

    Chemically, it’s unsurprising. Molecules as similar as Δ8- and Δ9-THC usually (though not always) act the same in the body. But legally it causes a lot of complications.

    The distinction between Δ8- and Δ9- originally came about from the congressional Farm Bill covering hemp growing and sales. Hemp is defined as a cannabis plant that has less than 0.3% Δ9-THC by dry weight. Anything that has more concentrated Δ9-THC than that is considered marijuana. Additionally, the Farm Bill said anything else naturally present in the hemp plant is legal. That includes Δ8-THC.

    “It’s creating a fight between marijuana and hemp” growers, says John Harloe, an attorney on Colorado’s THC taskforce. Products classified as marijuana “must be sold through dispensaries and pay high taxes, while hemp producers can sell essentially the same product but without the same regulations, due to the ambiguity in the Farm Bill,” Harloe says.

    Harloe is bringing Kinsey and Vanegas’s paper to the Colorado taskforce to inform the discussion. The taskforce is trying to create appropriate regulation that will address the different chemical variations of THC and guard public safety without crippling the hemp industry. The paper is particularly valuable because there is so little research done on THC and its intoxicating effects, due to federal rules.

    “Any bit of science is going to be influential,” Harloe says.

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    University of Connecticut

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  • Demonstration of Eco-friendly Hydrogen Combustor to Achieve Carbon Neutrality

    Demonstration of Eco-friendly Hydrogen Combustor to Achieve Carbon Neutrality

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    Newswise — An eco-friendly hydrogen combustor for domestic gas turbine that reduces carbon dioxide emissions has been developed and will be undergoing field test.

    The Korea Institute of Machinery and Materials (President Sang Jin Park, hereafter referred to as the KIMM), an institute under the jurisdiction of the Ministry of Science and ICT announced that it has developed a hydrogen co-firing combustor for gas turbines used in power generation. This is the first time that such technology has been developed in South Korea, and KIMM has plans to perform a demonstration of its application to power plants.

    Since July 2020, the research team led by Dr. Minkuk Kim, head of the Department of Zero-carbon Fuel and Power Generation at the KIMM Institute of Carbon Neutral Energy Machinery, has been developing an eco-friendly combustor for domestic gas turbines with 30% hydrogen co-firing, in collaboration with 13 industrial, academic, and research partners. A project for field demonstration will be started in 2023 with Korea East-West Power Company and Doosan Enerbility.

    Hydrogen is highly reactive fuel so there is a risk of high temperatures and flashback. In order to prevent such risks, KIMM improved a fuel injection method, including fuel split, staging and modifying fuel holes. These were applied to the heavy duty gas turbine developed by Doosan Enerbility. As a result, it was possible that NOx and combustion instability were suppressed to the same level of the original LNG gas turbine while burning a mixture of 30% hydrogen fuel.

    In the past, many efforts were made to promote the development of hydrogen co-firing combustors, but performance verification was difficult because there were no proper combustion test facilities in South Korea. So the combustor developed by KIMM was transferred to the German Aerospace Center (DLR) during the development process and successfully passed combustion tests in a high-pressure environment. These conditions mimic the actual operating conditions of the gas turbine, and its performance was verified accordingly. The development of hydrogen co-firing technology by domestic research institutes and its application to domestic gas turbines is a meaningful moment on the road to carbon neutrality in South Korea.

    When gas turbines use fuel blended with 30% hydrogen, CO2 emissions can be reduced by 10.4% compared to 100% LNG power generation. KIMM plans to increase the percentage of hydrogen contents in fuel over 50% thereby 21.4% reduction of CO2 by 2024. In addition, the team is a focusing its research efforts with the goal of developing a 100% carbon-free hydrogen combustion technology by 2030.

    KIMM also held a briefing on the development of a 300MW class gas turbine hydrogen co-firing combustor at the main office in Daejeon on October 12th. During this meeting, KIMM shared the details of their work on the core technology of modifying the hydrogen combustor. They also shared the results from Doosan Enerbility’s high-pressure combustion test results and announced Korea East-West Power Company’s Korea Institute of Future Convergence Technology’s plans to conduct power plant demonstrations of the hydrogen gas turbine.

    At the briefing session, KIMM President Sang Jin Park stated, “In order to transition to an eco-friendly and carbon-free energy society, it is essential to develop hydrogen fuel conversion technology for medium and large-sized gas turbines and to conduct demonstrations at power plants. Currently, developments of combustion and turbine system are in their final stages. A decision of turbine manufacturers Doosan Enerbility and Korea East-West Power Company to test the new engine’s performance has made it possible to secure domestic hydrogen turbine technology that much sooner.” He also emphasized, “In order for domestic technology to be commercialized in a timely manner without failing, the government’s interest and support in selecting a demonstration site are necessary. This is because such a process is otherwise impossible through the will of the private sector alone due to the nature of the power generation industry.”

    President Park added, “Unlike LNG heavy duty gas turbine in South Korea, which began as a fast follower, this hydrogen combustor is technologically equivalent to those from leading companies. If we can accelerate its commercialization through demonstration projects will help pave the way for South Korea’s next-generation new growth industry.”

     

     

     

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    The Korea Institute of Machinery and Materials (KIMM) is a non-profit government-funded research institute under the Ministry of Science and ICT. Since its foundation in 1976, KIMM is contributing to economic growth of the nation by performing R&D on key technologies in machinery and materials, conducting reliability test evaluation, and commercializing the developed products and technologies.

     

    These research efforts were carried out with the support of the Ministry of Trade, Industry and Energy’s project for the “Development of a 50% Eco-Friendly High Efficiency Gas Turbine Combustor for 300MWe-class Power Generation” (2020-2024, KETEP 20206710100030).

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    National Research Council of Science and Technology

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  • High levels of methane in the Nord Stream leak area

    High levels of methane in the Nord Stream leak area

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    Newswise — The scientific expedition to the Nord Stream leak from the University of Gothenburg has arrived back home. The researchers discovered that the methane levels near the leak were about 1,000 times higher than normal, but it’s too early to draw any conclusions from that discovery. The researchers have brought back heaps of samples to analyse.

    After five days at sea, the research vessel Skagerak is back home in Gothenburg. The hastily organised expedition to the Nord Stream leaks in the Baltic Sea is over, and the researchers are content with their efforts.

    “Everything has gone incredibly well, considering the short preparation time. In less than 48 hours, we got the researchers and equipment we wanted onboard,” says Katarina Abrahamsson, marine chemist at the University of Gothenburg, and coordinator for the expedition.

    German scientists assisted

    The methane gas leak was discovered on 26 September, and since then methane gas has continued to leak into the water. It was essential for the researchers to get to the area quickly to measure the effects of this large discharge, and to collect important data, says Abrahamsson. During a period of 54 hours, the expedition took 100–200 water samples.

    “In order to map the spread of the methane in the water, we had 20 different measurement locations at intervals of approximately 9–18 kilometres. At our assistance, we had researchers and equipment from the Alfred Wegener Institute in Germany. They have the knowledge to separate the pipeline methane from what occurs naturally, says Katarina Abrahamsson.

    What did you see?

    “In the water samples, we could see that the methane levels were up to 1,000 times higher than normal. Also, the distribution pattern of the methane from the leak was complicated and difficult to explain. A reason for this could be that we couldn’t measure the entire discharge, because the vessel was only permitted to go in Swedish waters. We simply didn’t have time to seek permission from Denmark,” says Katarina Abrahamsson.  

    Methane gas is dissolved in water, but when it reaches the surface, it transforms back to gas form and is emitted into the atmosphere. For how long the elevated levels of methane remain in the Baltic Sea depends on the currents, and when the leakage stops.

    Unclear effect on marine life

    It’s unclear what kind of effect these high methane levels could have on marine life. For example, there are bacteria in the water that can oxidize methane gas to grow and multiply.

    “I have filtered water samples during the expedition to see if there’s now been a growth of these types of bacteria when there are elevated methane levels in the water,” says Carina Bunse, marine biologist at the University of Gothenburg.

    Could it affect biological life in the Baltic Sea?

    “It’s autumn now, and soon it will be low season for phytoplankton and zooplankton. It could affect the food web locally if these methane-eating bacteria grow at the expense of other plankton species. But we can’t foresee the results. Before we can draw any conclusions, we have to make DNA analyses of the content in the water samples,” says Carina Bunse.

    Now, Skagerak is back in Gothenburg, and the researchers have a gigantic workload before them. Before anything could be said with certainty concerning the impact from the Nord Stream emissions on marine life in the long run, the water samples and measurements must be analysed and discussed. But the researchers are already making plans for new expeditions to the waters east of Bornholm.  

    “We now need to get an overview of our results, and then summarise them in an initial scientific paper. With a little luck, that could be published before the end of the year, says Katarina Abrahamsson.

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    University of Gothenburg

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  • Nobel panel to announce winner of chemistry prize

    Nobel panel to announce winner of chemistry prize

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    The winner, or winners, of the Nobel Prize in chemistry will be announced Wednesday at the Royal Swedish Academy of Sciences in Stockholm

    STOCKHOLM — The winner, or winners, of the Nobel Prize in chemistry will be announced Wednesday at the Royal Swedish Academy of Sciences in Stockholm.

    Last year the prize was awarded to scientists Benjamin List and David W.C. MacMillan for finding an ingenious and environmentally cleaner way to build molecules that the Nobel panel said is “already benefiting humankind greatly.”

    A week of Nobel Prize announcements kicked off Monday with Swedish scientist Svante Paabo receiving the award in medicine for unlocking secrets of Neanderthal DNA that provided key insights into our immune system.

    Three scientists jointly won the prize in physics Tuesday. Frenchman Alain Aspect, American John F. Clauser and Austrian Anton Zeilinger had shown that tiny particles can retain a connection with each other even when separated, a phenomenon known as quantum entanglement, that can be used for specialized computing and to encrypt information.

    The awards continue with literature on Thursday. The 2022 Nobel Peace Prize will be announced on Friday and the economics award on Monday.

    The prizes carry a cash award of 10 million Swedish kronor (nearly $900,000) and will be handed out on Dec. 10. The money comes from a bequest left by the prize’s creator, Swedish inventor Alfred Nobel, in 1895.

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    Follow all AP stories about the Nobel Prizes at https://apnews.com/hub/nobel-prizes

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