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Sunday, March 20, 2022

New form of ice discovered

Findings could have implications for our understanding of distant, water-rich planets

Date:: March 18, 2022
Source:: University of Nevada, Las Vegas
Summary:: Researchers have discovered a new form of ice, redefining the properties of water at high pressures.

UNLV researchers have discovered a new form of ice, redefining the properties of water at high pressures.

Solid water, or ice, is like many other materials in that it can form different solid materials based on variable temperature and pressure conditions, like carbon forming diamond or graphite. However, water is exceptional in this aspect as there are at least 20 solid forms of ice known to us.

A team of scientists working in UNLV's Nevada Extreme Conditions Lab pioneered a new method for measuring the properties of water under high pressure. The water sample was first squeezed between the tips of two opposite-facing diamonds -- freezing into several jumbled ice crystals. The ice was then subjected to a laser-heating technique that temporarily melted it before it quickly re-formed into a powder-like collection of tiny crystals.

By incrementally raising the pressure, and periodically blasting it with the laser beam, the team observed the water ice make the transition from a known cubic phase, Ice-VII, to the newly discovered intermediate, and tetragonal, phase, Ice-VIIt, before settling into another known phase, Ice-X.

Zach Grande, a UNLV Ph.D. student, led the work which also demonstrated that the transition to Ice-X, when water stiffens aggressively, occurs at much lower pressures than previously thought.

While it's unlikely we'll find this new phase of ice anywhere on the surface of Earth, it is likely a common ingredient within the mantle of Earth as well as in large moons and water-rich planets outside of our solar system.

The team's findings were reported in the March 17 issue of the journal Physical Review B.

Takeaways

The research team had been working to understand the behavior of high-pressure water that may be present in the interior of distant planets.

To do so, Grande and UNLV physicist Ashkan Salamat placed a sample of water between the tips of two round-cut diamonds known as diamond anvil cells, a standard feature in the field of high pressure physics. Applying a little bit of force to the diamonds enabled the researchers to recreate pressures as high as those found at the center of the Earth.

By squeezing the water sample between these diamonds, scientists drove the oxygen and hydrogen atoms into a variety of different arrangements, including the newly discovered arrangement, Ice-VIIt.

Not only did the first-of-its-kind laser-heating technique allow scientists to observe a new phase of water ice, but the team also found that the transition to Ice-X occurred at pressures nearly three times lower than previously thought -- at 300,000 atmospheres instead of 1 million. This transition has been a highly debated topic in the community for several decades.

"Zach's work has demonstrated that this transformation to an ionic state occurs at much, much lower pressures than ever thought before," Salamat said. "It's the missing piece, and the most precise measurements ever on water at these conditions."

The work also recalibrates our understanding of the composition of exoplanets, Salamat added. Researchers hypothesize that the Ice-VIIt phase of ice could exist in abundance in the crust and upper mantle of expected water-rich planets outside of our solar system, meaning they could have conditions habitable for life.

Story Source:

Materials provided by University of Nevada, Las Vegas. Original written by Natalie Bruzda. Note: Content may be edited for style and length.

Journal Reference:

Zachary M. Grande, C. Huy Pham, Dean Smith, John H. Boisvert, Chenliang Huang, Jesse S. Smith, Nir Goldman, Jonathan L. Belof, Oliver Tschauner, Jason H. Steffen, Ashkan Salamat. Pressure-driven symmetry transitions in dense H2O ice. Physical Review B, 2022; 105 (10) DOI: 10.1103/PhysRevB.105.104109

Cite This Page:

University of Nevada, Las Vegas. "New form of ice discovered: Findings could have implications for our understanding of distant, water-rich planets." ScienceDaily. ScienceDaily, 18 March 2022. <www.sciencedaily.com/releases/2022/03/220318170514.htm>.

The oxidation of volcanoes -- a magma opus

Date:: March 17, 2022
Source:: Yale University
Summary:: A new study unlocks the science behind a key ingredient -- namely oxygen -- in some of the world's most violent volcanoes. The research offers a new model for understanding the oxidation state of arc magmas, the lavas that form some volcanoes, such as the one that erupted dramatically in Tonga earlier this year. The plume from Tonga's underwater volcanic eruption on Jan. 15 rose 36 miles into the air. Ash from the volcano reached the mesosphere, Earth's third layer of atmosphere.

A new, Yale-led study unlocks the science behind a key ingredient -- namely oxygen -- in some of the world's most violent volcanoes.

The research offers a new model for understanding the oxidation state of arc magmas, the lavas that form some volcanoes, such as the one that erupted dramatically in Tonga earlier this year.

The plume from Tonga's underwater volcanic eruption on Jan. 15 rose 36 miles into the air. Ash from the volcano reached the mesosphere, Earth's third layer of atmosphere.

"These eruptions occur in volcanic arcs, such as the Aleutian island chain, which are well known in the circum-Pacific region and produce the world's most explosive volcanic eruptions," said Jay Ague, the Henry Barnard Davis Memorial Professor of Earth & Planetary Sciences at Yale.

Ague is first author of the new study, published in the journal Nature Geoscience. Ague is also curator-in-charge of mineralogy and meteoritics for the Yale Peabody Museum of Natural History.

Scientists have long known that arc magmas have a higher oxidation state than rocks in most of the Earth's mantle (its upper, rocky layer). This is surprising, they say, because arc magmas form in the mantle. There has been no consensus on the origins of the oxidizing signature.

Ague and his colleagues say the process begins with a layer of sediment that covers tectonic plates beneath the ocean floor. Tectonic plates are large slabs of rock that jockey for position in the Earth's crust and upper mantle.

The sediment covering these ocean plates is largely made up of weathered materials shed from continents or produced as a result of seafloor hydrothermal vent activity. Giant tube worms and other exotic sea creatures commonly thrive near these vents. But regardless of origin, the sediments covering oceanic plates are often highly oxidized.

Tectonic plates are constantly in motion, moving at about the rate that fingernails grow. Oceanic plates are generated at mid-ocean ridges and sink sharply into Earth's interior -- in a process called subduction.

That's where things get interesting for arc volcanism, Ague said.

When an ocean plate subducts, Ague explained, it heats up, is compressed, and begins to dehydrate. This metamorphism produces hot, water-rich fluids that rise toward the surface.

As these materials move upward through the oxidized sediment layer on top of slabs, the fluids themselves become oxidized -- setting the stage for an arc magma.

"As the fluids continue to rise they leave the slab behind and enter Earth's mantle," Ague said. "There, the fluids drive mantle melting, producing oxidized magmas that ascend and can ultimately erupt as lava from volcanoes."

Beyond the dramatic effects of volcanic eruptions, the oxidized character of arc magmas is also geologically significant, Ague said. Oxidation is critical for making certain kinds of ore deposits, particularly copper and gold, such as those found in western South America.

Also, the injection of highly-oxidized, sulfur-bearing gases into the atmosphere after an eruption can lead to transient global cooling of the troposphere, the lowest level of Earth's atmosphere.

"This was the case with the 1991 eruption of Mount Pinatubo in the Philippines," Ague said. "It also occurred in a number of famous historical cases, such Mount Tambora in Indonesia in 1815. That was the most powerful volcanic eruption in human history and led to the so-called 'Year Without a Summer' in 1816."

Santiago Tassara, a Bateman Postdoctoral Associate in Yale's Department of Earth & Planetary Sciences, is a co-author of the new study. Other co-authors include researchers from Cornell University, the Chinese Academy of Sciences, the National Museum of Natural History at the Smithsonian Institution, Freie Universität Berlin, and the University of Crete.

Story Source:

Materials provided by Yale University. Original written by Jim Shelton. Note: Content may be edited for style and length.

Journal Reference:

Ague, J.J., Tassara, S., Holycross, M.E. et al. Slab-derived devolatilization fluids oxidized by subducted metasedimentary rocks. Nat. Geosci., 2022 DOI: 10.1038/s41561-022-00904-7

Yale University. "The oxidation of volcanoes -- a magma opus." ScienceDaily. ScienceDaily, 17 March 2022.

Effects of ancient carbon releases suggest possible scenarios for future climate

Date:: March 16, 2022
Source:: University of California - Santa Cruz
Summary:: A massive release of greenhouse gases, likely triggered by volcanic activity, caused a period of extreme global warming known as the Paleocene-Eocene Thermal Maximum (PETM) about 56 million years ago. A new study now confirms that the PETM was preceded by a smaller episode of warming and ocean acidification caused by a shorter burst of carbon emissions. The short-lived precursor event represents what might happen if current emissions can be shut down quickly, while the much more extreme global warming of the PETM shows the consequences of continuing to release carbon into the atmosphere at the current rate.

A massive release of greenhouse gases, likely triggered by volcanic activity, caused a period of extreme global warming known as the Paleocene-Eocene Thermal Maximum (PETM) about 56 million years ago. A new study now confirms that the PETM was preceded by a smaller episode of warming and ocean acidification caused by a shorter burst of carbon emissions.

The new findings, published March 16 in Science Advances, indicate that the amount of carbon released into the atmosphere during this precursor event was about the same as the current cumulative carbon emissions from the burning of fossil fuels and other human activities. As a result, the short-lived precursor event represents what might happen if current emissions can be shut down quickly, while the much more extreme global warming of the PETM shows the consequences of continuing to release carbon into the atmosphere at the current rate.

"It was a short-lived burp of carbon equivalent to what we've already released from anthropogenic emissions," said coauthor James Zachos, professor of Earth and planetary sciences and Ida Benson Lynn Chair of Ocean Health at UC Santa Cruz. "If we turned off emissions today, that carbon would eventually get mixed into the deep sea and its signal would disappear, because the deep-sea reservoir is so huge."

This process would take hundreds of years -- a long time by human standards, but short compared to the tens of thousands of years it took for Earth's climate system to recover from the more extreme PETM.

The new findings are based on an analysis of marine sediments that were deposited in shallow waters along the U.S. Atlantic coast and are now part of the Atlantic Coastal Plain. At the time of the PETM, sea levels were higher, and much of Maryland, Delaware, and New Jersey were under water. The U.S. Geological Survey (USGS) has drilled sediment cores from this region which the researchers used for the study.

The PETM is marked in marine sediments by a major shift in carbon isotope composition and other evidence of dramatic changes in ocean chemistry as a result of the ocean absorbing large amounts of carbon dioxide from the atmosphere. The marine sediments contain the microscopic shells of tiny sea creatures called foraminifera that lived in the surface waters of the ocean. The chemical composition of these shells records the environmental conditions in which they formed and reveals evidence of warmer surface water temperatures and ocean acidification.

First author Tali Babila began the study as a postdoctoral fellow working with Zachos at UC Santa Cruz and is now at the University of Southampton, U.K. Novel analytical methods developed at Southampton enabled the researchers to analyze the boron isotope composition of individual foraminifera to reconstruct a detailed record of ocean acidification. This was part of a suite of geochemical analyses they used to reconstruct environmental changes during the precursor event and the main PETM.

"Previously, thousands of foraminifera fossil shells were needed for boron isotope measurement. Now we are able to analyze a single shell that's only the size of a grain of sand," Babila said.

Evidence of a precursor warming event had been identified previously in sediments from the continental section at Big Horn Basin in Wyoming and a few other sites. Whether it was a global signal remained unclear, however, as it was absent from deep-sea sediment cores. Zachos said this makes sense because sedimentation rates in the deep ocean are slow, and the signal from a short-lived event would be lost due to mixing of sediments by bottom-dwelling marine life.

"The best hope for seeing the signal would be in shallow marine basins where sedimentation rates are higher," he said. "The problem there is that deposition is episodic and erosion is more likely. So there's not a high likelihood of capturing it."

The USGS and others have drilled numerous sediment cores (or sections) along the Atlantic Coastal Plain. The researchers found that the PETM is present in all of those sections, and several also capture the precursor event. Two sections from Maryland (at South Dover Bridge and Cambridge-Dover Airport) are the focus of the new study.

"Here we have the full signal, and a couple of other locations capture part of it. We believe it's the same event they found in the Bighorn Basin," Zachos said.

Based on their analyses, the team concluded that the precursor signal in the Maryland sections represents a global event that probably lasted for a few centuries, or possibly several millennia at most.

The two carbon pulses -- the short-lived precursor and the much larger and more prolonged carbon emissions that drove the PETM -- led to profoundly different mechanisms and time scales for the recovery of the Earth's carbon cycle and climate system. The carbon absorbed by the surface waters during the precursor event got mixed into the deep ocean within a thousand years or so. The carbon emissions during the PETM, however, exceeded the buffering capacity of the ocean, and removal of the excess carbon depended on much slower processes such as the weathering of silicate rocks over tens of thousands of years.

Zachos noted that there are important differences between Earth's climate system today and during the Paleocene -- notably the presence of polar ice sheets today, which increase the sensitivity of the climate to greenhouse warming.

In addition to Babila and Zachos, the coauthors of the paper include Gavin Foster and Christopher Standish at University of Southampton; Donald Penman at Utah State University; Monika Doubrawa, Robert Speijer, and Peter Stassen at KU Leuven, Belgium; Timothy Bralower at Pennsylvania State University; and Marci Robinson and Jean Self-Trail at the USGS. This work was funded in part by the National Science Foundation.

Story Source:

Materials provided by University of California - Santa Cruz. Original written by Tim Stephens. Note: Content may be edited for style and length.

Related Multimedia:

Microscopic shells of organisms called foraminifera

Journal Reference:

Tali L. Babila, Donald E. Penman, Christopher D. Standish, Monika Doubrawa, Timothy J. Bralower, Marci M. Robinson, Jean M. Self-Trail, Robert P. Speijer, Peter Stassen, Gavin L. Foster, James C. Zachos. Surface ocean warming and acidification driven by rapid carbon release precedes Paleocene-Eocene Thermal Maximum. Science Advances, 2022; 8 (11) DOI: 10.1126/sciadv.abg1025

University of California - Santa Cruz. "Effects of ancient carbon releases suggest possible scenarios for future climate." ScienceDaily. ScienceDaily, 16 March 2022.

Conversion process turns pollution into cash

Converting carbon dioxide to ethylene holds commercial promise, professor says

Date:: March 18, 2022
Source:: University of Cincinnati
Summary:: Engineers have developed a promising electrochemical system to convert emissions from chemical and power plants into useful products while addressing climate change.

Engineers at the University of Cincinnati have developed a promising electrochemical system to convert emissions from chemical and power plants into useful products while addressing climate change.

UC College of Engineering and Applied Science assistant professor Jingjie Wu and his students used a two-step cascade reaction to convert carbon dioxide to carbon monoxide and then into ethylene, a chemical used in everything from food packaging to tires.

The study was published in the journal Nature Catalysis in collaboration with the University of California Berkeley and the Lawrence Berkeley National Laboratory.

UC College of Engineering and Applied Science graduate Tianyu Zhang, one of the study's lead authors, led a similar study last year that examined ways to convert carbon dioxide into methane that could be used as rocket fuel for Martian exploration.

"The significance of the two-stage conversion is that we can increase the ethylene selectivity and productivity at the same time with the low-cost strategy," Zhang said. "This process can be applied to various reactions because the electrode structure is general and simple."

Selectivity means isolating the desired compounds. Productivity is the amount of ethylene the reactor can produce.

"We're selectively reducing carbon emissions into something considered valuable because of its many downstream applications," Zhang said.

Applications include a variety of industries from steel and cement plants to the oil and gas industry, he said.

"In the future, we can use this technique to reduce carbon emissions and make a profit from it. So, reducing carbon emissions will not be a costly process anymore," he said.

Ethylene has been called "the world's most important chemical." It's used in a range of plastics from water bottles to PVC pipe, textiles and rubber found in tires and insulation.

Professor Wu said the chemical they produce is known as "green ethylene," because it is created from renewable sources.

"Ideally we can remove greenhouse gas from the environment while simultaneously making fuels and chemicals," Wu said. "Power plants and ethylene plants emit a lot of carbon dioxide. Our goal is to capture the carbon dioxide and convert it to ethylene using electrochemical conversion."

So far, the process requires more energy than it produces in ethylene. By using tandem electrodes, UC engineers were able to boost productivity and selectivity, both of which are key indicators toward making the process commercially attractive to industry, Wu said.

There are huge environmental advantages to containing and converting greenhouse gases, Wu said.

"It's being pushed by the government. In the future, we'll need sustainable development so we'll need to convert carbon dioxide," he said.

And Wu said copper isn't necessarily the best catalyst for this reaction, so industry experts have likely alternatives that could boost productivity and efficiency even more.

"Our system is very general, but you can use preferred catalysts," Wu said. "But even with commercial copper we were able to more than double the performance. With an even better catalyst, we could solve the economic issue."

Wu last year applied for patents for their design.

Zhang said the system will take some time to become economical. But already they have made tremendous strides, he said.

"The technology has improved a lot in 10 years. So in the next 10 years, I'm optimistic we'll see similar advances. This is a game changer," Zhang said.

Story Source:

Materials provided by University of Cincinnati. Original written by Michael Miller. Note: Content may be edited for style and length.

Journal Reference:

Tianyu Zhang, Justin C. Bui, Zhengyuan Li, Alexis T. Bell, Adam Z. Weber, Jingjie Wu. Highly selective and productive reduction of carbon dioxide to multicarbon products via in situ CO management using segmented tandem electrodes. Nature Catalysis, 2022; DOI: 10.1038/s41929-022-00751-0

University of Cincinnati. "Conversion process turns pollution into cash: Converting carbon dioxide to ethylene holds commercial promise, professor says." ScienceDaily. ScienceDaily, 18 March 2022. <www.sciencedaily.com/releases/2022/03/220318161451.htm>.

Smart coatings in the pipeline

Made from cheap chemicals, this polymer packs a punch

Date:: March 20, 2022
Source:: Flinders University
Summary:: An imaginative approach to polymer surface coating has produced a sustainable way to remove mercury from water -- while providing a wide range of protection including for preventing metal corrosion and solvent damage of plastic PVC pipes. The smart coating, made from low-cost chemicals from oil refining and other sources, also can prevent acid and water damage of concrete surfaces and be repaired in situ by a simple heating process.

An imaginative approach to polymer surface coating has produced a sustainable way to remove mercury from water -- while providing a wide range of protection including for preventing metal corrosion and solvent damage of plastic PVC pipes.

The smart coating, made from low-cost chemicals from oil refining and other sources, also can prevent acid and water damage of concrete surfaces and be repaired in situ by a simple heating process, says Flinders University project leader Max Mann.

"Made easily from elemental sulfur and dicyclopentadiene (DCPD is a by-product of petroleum refining), this new coating is multi-functional which gives us wide scope to use it in a wide range of useful ways and for longer lasting industrial products and components," says Flinders University PhD candidate Mr Mann, lead author of the cover article in this month's issue of Polymer Chemistry.

"This exciting new area of research extends fundamental chemistry to several practical applications."

"The method for making the coating is safer than methods previously used for related coatings. The team developed a lower temperature process that prevented runaway reactions," adds co-author University of Liverpool researcher Dr Bowen Zhang.

Along with its protective powers against corrosion, solvent damage and acid and water damage, the research found the active coating can capture toxic metals such as mercury.

The coating is repairable and scratches and damage can be prepared by the simple application of heat, the Flinders-Liverpool team found.

This process is possible because of the coating's chemical structure which allows sulfur-sulfur bonds to be broken and re-formed.

Flinders University chemistry Professor Justin Chalker says the research is a significant step forward in multi-functional coatings.

"The unique chemical composition of the smart coating enables protection of substrates, active removal of toxic mercury species from water and oil, and is repairable which ensures its sustainability," says Matthew Flinders Professor Chalker, from the Institute of Nanoscale Science and Technology at Flinders University.

"The coating is solvent resistant and can also remove mercury from oil and water mixtures, which is of importance to remediation in the petroleum and gas industry."

Mr Mann conducted part of this study in the UK on an exchange at Dr Tom Hasell's University of Liverpool lab as part of ongoing collaboration between the Chalker Lab and Hasell Lab in Liverpool.

The project was funded by the Australian Research Council (DP200100090).

Story Source:

Materials provided by Flinders University. Note: Content may be edited for style and length.

Journal Reference:

Maximilian Mann, Bowen Zhang, Samuel J. Tonkin, Christopher T. Gibson, Zhongfan Jia, Tom Hasell, Justin M. Chalker. Processes for coating surfaces with a copolymer made from sulfur and dicyclopentadiene. Polymer Chemistry, 2022; 13 (10): 1320 DOI: 10.1039/D1PY01416A

Flinders University. "Smart coatings in the pipeline: Made from cheap chemicals, this polymer packs a punch." ScienceDaily. ScienceDaily, 20 March 2022. <www.sciencedaily.com/releases/2022/03/220315095015.htm>.

Cheaper, more efficient ways to capture carbon

Date:: March 16, 2022
Source:: University of Colorado at Boulder
Summary:: Researchers have developed a new tool that could lead to more efficient and cheaper technologies for capturing heat-trapping gases from the atmosphere and converting them into beneficial substances, like fuel or building materials.

University of Colorado Boulder researchers have developed a new tool that could lead to more efficient and cheaper technologies for capturing heat-trapping gases from the atmosphere and converting them into beneficial substances, like fuel or building materials. Such carbon capture technology may be needed at scale in order to limit global warning this century to 2.7 degrees F (1.5 Celsius) above pre-industrial temperatures and fend off catastrophic impacts of global climate change.

The scientists describe their technique in a paper published this month in the journal iSCIENCE.

The method predicts how strong the bond will be between carbon dioxide and the molecule that traps it, known as a binder. This electrochemical diagnosis can be easily applied to any molecule that is chemically inclined to bind with carbon dioxide, allowing researchers to identify suitable molecular candidates with which to capture carbon dioxide from everyday air.

"The Holy Grail, if you will, is to try to inch toward being able to use binders that can grab carbon dioxide from the air [around us], not just concentrated sources," said Oana Luca, co-author of the new study and assistant professor of chemistry. "Determining the strength of binders allows us to figure out whether the binding will be strong or weak, and identify candidates for future study for direct carbon capture from dilute sources."

The goal of carbon capture and storage technology is to remove carbon dioxide from the atmosphere and store it safely for hundreds or thousands of years. But while it has been in use in the U.S. since the 1970s, it currently captures and stores a mere 0.1% of global carbon emissions annually. To help meet carbon emissions goals laid out by the IPCC, carbon capture and storage would have to rapidly increase in scale by 2050.

Current industrial facilities around the world rely on capturing carbon dioxide from a concentrated source, such as emissions from power plants. While these methods can bind a lot of carbon dioxide quickly and efficiently using large amounts of certain chemical binders, they are also extraordinarily energy intensive.

This method also is quite expensive at scale to take carbon dioxide and turn it into something else useful, such as carbonates, an ingredient in cement, or formaldehyde or methanol, which can be used as a fuel, according to Luca, fellow-elect of the Renewable and Sustainable Energy Institute (RASEI).

Using electrochemical methods instead, such as those detailed in the new CU Boulder-led study, would free carbon capture facilities from being tied to concentrated sources, allowing them to exist almost anywhere.

Being able to easily estimate the strength of chemical bonds also enables researchers to screen for which binders will be best suited -- and offer a cheaper alternative to traditional methods -- for capturing and converting carbon into materials or fuel according to Haley Petersen, co-lead author on the study and graduate student in chemistry.

Creating chemical bonds

The science of chemistry is based on a few basic facts: One, that molecules are made of atoms, and two, that they are orbited by electrons. When atoms bond with other atoms, they form molecules. And when atoms share electrons with other atoms, they form what is called a covalent bond.

Using electricity, the researchers can activate these bonds by using an electrode to deliver an electron to a molecule. When they do that to an imidazolium molecule, like they did in this study, a hydrogen atom is removed, creating a gap in a carbon atom for another molecule to want to bond with it -- such as carbon dioxide.

However, carbon dioxide (CO2) is the kind of molecule that doesn't typically like to create new bonds.

"It's generally unreactive, and in order to react with it, you also have to bend it," said Luca. "So we're in a chemical space that hasn't really been probed before, for CO2 capture."

The method the researchers examines how good a whole family of carbenes (a specific type of molecule, containing a neutral carbon atom), that they can electrochemically generate, are at binding CO2.

"Just by looking at very simple molecules -- molecules that we can make, molecules that we can modify -- we can obtain a map of the energetics for electrochemical carbon capture. It is a small leap for now, but possibly a big leap down the line," said Luca.

This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE 2040434.

Story Source:

Materials provided by University of Colorado at Boulder. Original written by Kelsey Simpkins. Note: Content may be edited for style and length.

Journal Reference:

Haley A. Petersen, Abdulaziz W. Alherz, Taylor A. Stinson, Chloe G. Huntzinger, Charles B. Musgrave, Oana R. Luca. Predictive energetic tuning of C-Nucleophiles for the electrochemical capture of carbon dioxide. iScience, 2022; 25 (4): 103997 DOI: 10.1016/j.isci.2022.103997

University of Colorado at Boulder. "Cheaper, more efficient ways to capture carbon." ScienceDaily. ScienceDaily, 16 March 2022.

LETTING FOLKS DRINK COFFEE IN THE LAB

Waste coffee grounds could someday help detect brain waves

by American Chemical Society

There's nothing like a steaming cup of joe to give your morning a quick boost. Now, there's yet another reason to love the beverage. Today, researchers report the first application of used coffee grounds as environmentally friendly electrode coatings for sensitive neurochemistry measurements. The material could eventually help scientists get a better handle on brain activity and detect minute levels of neurotransmitters.

The researchers will present their results at the spring meeting of the American Chemical Society (ACS).

Spent coffee grounds have previously been used to make porous carbon supercapacitors for energy storage. But now, new research led by principal investigator Ashley Ross, Ph.D., has taken recycled coffee waste in another, more biological direction. She and her team have demonstrated that electrodes coated with carbon from this waste can detect trace levels of biomolecules in vitro. According to Ross, this is the first example of residual coffee grounds being repurposed for biosensing applications.

"I saw papers about using spent grounds to produce porous carbon for energy storage, and I thought maybe we could use this conductive material in our neurochemistry detection work," says Ross. "And I also thought this would be a good excuse to buy lots of coffee for the lab!" Ross, who is at the University of Cincinnati, and several members of her team are self-professed coffee lovers.

The traditional microelectrodes that neuroscientists use are commonly made from carbon fiber—fine, solid carbon strands bundled together. Making them is typically an arduous and expensive process, involving multiple steps and harsh chemicals. Eventually, Ross wants to fabricate entire electrodes with carbon from coffee grounds because this type of approach would be inexpensive and environmentally friendly. As a first step toward realizing that goal, the researchers adapted the material from the grounds as a coating for conventional electrodes.

Kamya Lapsley, who was a summer student in Ross's lab and who is currently an undergraduate student at Kent State University, took this initial challenge on. She and other members of the lab dried used coffee grounds and heated them in a tube furnace at about 1,300 F. Next, they added the material to a potassium hydroxide solution to activate the carbon and open up holes in the structure. Then, the researchers heated the mixture again under nitrogen gas to remove any undesired byproducts. What was left was an inky slurry full of flecks of porous carbon. As a final step, the researchers diluted the sludge with water, into which they dipped the carbon fiber electrodes to coat them with a layer of porous carbon nearly a hundred times thinner than the diameter of a human hair.

The researchers compared the performance of coated and uncoated electrodes for sensing small quantities of dopamine, a neurotransmitter, with fast-scan cyclic voltammetry. With this technique, they applied a rapidly varying voltage to the electrode to alternately oxidize and reduce dopamine. The technique is fast enough to detect subsecond neurotransmitter release, as would happen in the brain. The researchers found that electrodes coated with porous carbon reached oxidative current levels over three times higher than bare carbon fibers in the presence of dopamine, indicating that the coated electrode offered a more sensitive surface for dopamine detection. Not only does the porous structure allow more dopamine molecules to participate in the reaction because of the coating's large surface area, it also momentarily traps dopamine molecules in the crevices of the electrode, says Ross. These properties increase the sensitivity and allow the researchers to carry out faster measurements. The group is now exploring how these porous coatings impact the temporal resolution of the technique.

Next, the team will make carbon fiber electrodes from scratch with porous carbon from waste coffee grounds, which would give the electrodes uniform porosity not just on the surface, but also through and through. Ross predicts that this will boost their neurochemical detection abilities because an even larger total surface area of the electrode will be exposed to adsorb the dopamine molecules. At the same time, Ross plans to put the current coffee-coated electrodes to the test in the brains of live rats.

In the meantime, there will be no lack of starting materials to carry out the next stages of the project, for the entire lab seems to love their brew. "The grad students provided quite a bit of coffee grounds—more than we will ever need," says Ross. "My entire lab really loved this project."Chemists synthesize electrodes for accumulators from coffee grounds

More information: Deriving porous carbon from waste coffee grounds for sensitive dopamine detection with fast-scan cyclic voltammetry, ACS Spring 2022. acs.digitellinc.com/acs/live/22/page/677

Provided by American Chemical Society

How Spanish cinema hit the big time

Four Spaniards are tapped for an Oscar, -- animator Alberto Mielgo, Spain's Hollywood couple Javier Bardem and Penelope Cruz, and Basque composer Alberto Iglesias (AFP/LLUIS GENE)

Marie GIFFARD
Sun, March 20, 2022

With a Golden Bear for Spanish director Carla Simon and four compatriots nominated for Oscars, including superstars Javier Bardem and Penelope Cruz, Spanish cinema has now begun to captivate a global audience.

When Bardem and Cruz, who have been married for over a decade, were both tapped for Oscars, the 53-year-old actor could hardly contain his excitement.

"The fact that (Penelope's) nomination was for a role in Spanish... seems really extraordinary, even historic in terms of the Spanish brand," he said in February.

Unlike other countries with a long and distinguished history of cinema, Spain has struggled to establish itself on the international stage.

So far, Luis Bunuel has been the only Spanish director to win the coveted Palme D'Or at Cannes Film Festival for his provocative 1961 feature "Viridiana".

But all that is changing, with Spanish cinema increasingly recognised for its contribution to the silver screen, the most recent being Carla Simon's triumph at this year's Berlinale where she took the top prize for "Alcarras" (2022), a Catalan drama about peach farmers.

And according to Variety magazine, Cruz is rumoured to be in the running for president of the jury at Cannes, an honour already bestowed upon the legendary Pedro Almodovar, by far Spain's best-known filmmaker.

Cruz herself is the only Spanish actress ever to win an Oscar, taking home the gong in 2009 for best supporting actress in the Woody Allen comedy "Vicky Cristina Barcelona".

And if she wins best actress at the Oscars later this month for Almodovar's "Parallel Mothers", it will be a coup for a film entirely "Made in Spain", whose soundtrack has also been nominated for best original score.

- Years of work by film schools -

The score was written by Basque composer Alberto Iglesias, who has worked with Almodovar for two decades on 13 of his films. This is the fourth time an Iglesias soundtrack has been nominated for an Oscar.

For him, there is "strong momentum" within Spanish cinema.

"There is an energy... it has to do with the film schools that have been working for a long time to create new filmmakers," he told AFP.

"It has been really difficult for Spanish cinema to cross the threshold and get into these big international festivals," explains Pilar Martinez-Vasseur, director of the Spanish Film Festival in the French city of Nantes.

Spanish films which have received acclaim abroad are often not identified as such, she said, pointing to the 2001 psychological thriller "The Others" starring Nicole Kidman which was directed by Spain's Alejandro Amenabar.

"In Spain, we still have the idea that Spanish cinema is bad, that it's a nest of communists, that filmmakers are pampered, they do nothing and get subsidies," she said, calling for greater support from the government.

Filmmaking in Spain receives far less state aid than in France, experts say.

Spanish cinema has had to "learn how to break into a globalised ecosystem," said Beatriz Navas who heads the Institute of Cinematography and Audiovisual Arts (ICAA), which is subsidised by the culture ministry.

"This hasn't happened overnight because you need some sort of 'greenhouse' environment where filmmakers can work with freedom," she told AFP.

"And the 'incubation time' needs to be sufficient for these productions to achieve the recognition and prestige they deserve."

- 'Spanish cinema's best moment' -

As well as Cruz, Bardem and Iglesias, Spain also has a fourth horse in the Oscar race in the shape of Alberto Mielgo's "The Windshield Wiper" which has been nominated for best animated short film.

"This is the best moment for Spanish cinema," said Jose Luis Rebordinos, director of the prestigious San Sebastian film festival.

"We are making a lot of cinema and audiovisual productions in Spain, as well as for streaming platforms which is bringing a lot of work so Spanish film technicians are getting better and better," he said.

Spain's Western-friendly landscapes have drawn Hollywood directors since the 1960s and is becoming an increasingly popular destination for filming series -- Netflix, which set up its first European studios in Madrid in 2019, scored huge hits with "Money Heist" and "Elite".

Last year, the government said it wanted Spain to become Europe's "audiovisual hub", pledging to inject 1.6 billion euros to expand the film and TV production sector by 30 percent by 2025.

"International critics are increasingly focusing on our cinematic output thanks to figures like Almodovar, Javier Bardem and Penelope Cruz," said Rebordinos.

"They are finding ways to draw more attention to Spanish cinema."

mig/hmw/bp/oho

Body composting takes root in US 'green' burial trend

Agence France-Presse

Return Home CEO Micah Truman holds a sample bag containing composted animal remains during a tour of the Return Home funeral home which specializes in human composting in Auburn, Washington on March 14, 2022.

AFP PHOTO

'Dying better'

"It's like these people are teaching us to die better," Return Home founder and chief Micah Truman said as he showed AFP a warehouse-sized room with racks of metal containers referred to as "vessels," which hold remains during the 60-day, sealed decomposition process.

The space was brightly lit and upbeat music played. Loved ones who visit during those 60 days can pick songs celebrating the lives of those they have lost.

Bodies in vessels are not embalmed, and family members are invited to add flowers or compostable mementos to the straw and other natural ingredients used in the process.

The amount of organic material added to the vessels to help in the composting process is about triple the body weight of the human remains inside, resulting in hundreds of pounds of compost being produced.

No enzymes are added, the company said.

Sensors tracking moisture, temperature and air flow synched with a computer to optimize conditions for decomposition.

Halfway through the process, bones are removed and ground into fine pieces before being put back in the vessel to finish composting.

The result looks and feels like ordinary mulch.

Families can take as much or as little as they want, with the rest spread at "The Woodland" in Kent.

Local zoning rules restrict the land — which was once strewn with ruined cars, some scarred by bullets — from ever being built on.

Green burial

Body composting is part of an eco-friendly funeral trend gaining momentum around the world, according to Green Burial Council president Edward Bixby.

"Basically, it's going back to the earth as we came; dust to dust," said Bixby, who opened his first Destination Destiny natural burial cemetery five years ago in New Jersey and has expanded to ten US states.

The council has more than 400 members, some outside the United States, according to Bixby.

A single cremation, according to the Green Burial Council, burns about as much fuel as a full tank of a large sport utility vehicle.

Return Home body composting is priced at $5,000, on par with cremation. Traditional funerals can cost double or triple that.

Other green burial options include simply wrapping a body in a biodegradable shroud or putting it in a wooden box and burying it.

Silicon Valley-based Coeio sells an Infinity Burial Suit that contains mushroom mycelium in a recipe intended to "neutralize toxins found in the body and transfer nutrients to plant life."

Green burials come with a natural approach to death itself.

Loved ones can be involved with preparing bodies for burial, seeing the departed as being a part of life that continues on.

"Horror movies and things like that have made people afraid of death and dying," Bixby said.

"We have always had the ability to care for our loved ones in death, we just lost touch with it."

A demonstration "vessel" for the deceased is pictured (R) among the other vessels during a tour of the Return Home funeral home which specializes in human composting in Auburn, Washington on March 14, 2022 (AFP/Jason Redmond)