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  • richardmitnick 8:15 am on July 19, 2019 Permalink | Reply
    Tags: "Bioengineers shed light on folding genomes", , “3D Epigenetics”, , Chemistry,   

    From Penn Today: “Bioengineers shed light on folding genomes” 


    From Penn Today

    July 18, 2019

    A light-triggered technique that allows genomes to be folded into specific configurations at high speeds has potential to advance the field of 3D epigenetics.

    1

    The genome is identical in every cell of the body. However, this tightly-packed genetic material isn’t always folded into the same shape in each cell. The folding pattern can lead to variations in which genes are activated to make proteins.

    A genome can be thought of as a beaded string, with each bead representing a gene. Reporting in Nature Methods, Jennifer Phillips-Cremins, an assistant professor in Penn Engineering’s Department of Bioengineering, led a team in using light to force both ends of that string together, folding it into specific shapes so that certain genes are in direct physical contact with each other. By controlling which genes are touching, Phillips-Cremins and colleagues hope to determine how different configurations lead to different combinations of genes that are expressed in the body.

    This field of genomic shape manipulation is known as “3D Epigenetics,” and Phillips-Cremins is one of the researchers at its forefront. Her team’s light-triggered folding method, known as light-activated dynamic looping (LADL), can fold genomes into specific loops in a matter of hours. The loops are temporary and can be easily undone. Since prior research from the Phillips-Cremins lab indicates that these looping mechanisms may play a role in some neurodevelopmental diseases, this speedy new folding tool may one day be of use in further research or even treatments.

    “It is critical to understand the genome structure-function relationship on short timescales because the spatiotemporal regulation of gene expression is essential to faithful human development and because the mis-expression of genes often goes wrong in human disease,” Phillips-Cremins says. “The engineering of genome topology with light opens up new possibilities to understanding the cause-and-effect of this relationship. Moreover we anticipate that, over the long term, the use of light will allow us to target specific human tissues and even to control looping in specific neuron subtypes in the brain.”

    See the full article here .

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    Please help promote STEM in your local schools.

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    U Penn campus

    Academic life at Penn is unparalleled, with 100 countries and every U.S. state represented in one of the Ivy League’s most diverse student bodies. Consistently ranked among the top 10 universities in the country, Penn enrolls 10,000 undergraduate students and welcomes an additional 10,000 students to our world-renowned graduate and professional schools.

    Penn’s award-winning educators and scholars encourage students to pursue inquiry and discovery, follow their passions, and address the world’s most challenging problems through an interdisciplinary approach.

     
  • richardmitnick 9:24 am on July 18, 2019 Permalink | Reply
    Tags: "A Graphene Superconductor That Plays More Than One Tune", , Chemistry, , Moiré superlattice, , , Superconductor/insulator, Trilayer graphene/boron nitride heterostructure device   

    From Lawrence Berkeley National Lab: “A Graphene Superconductor That Plays More Than One Tune” 

    Berkeley Logo

    From Lawrence Berkeley National Lab

    July 17, 2019
    Theresa Duque
    tnduque@lbl.gov
    510-495-2418

    1
    Schematic of graphene/boron nitride moire’ superlattice superconductor/insulator device: The heterostructure material is composed of three atomically thin (2D) layers of graphene (gray) sandwiched between 2D layers of boron nitride (red and blue) to form a repeating pattern called a moiré superlattice. Superconductivity is indicated by the light-green circles, which represent the hole (positive charge) sitting on each unit cell of the moiré superlattice. (Credit: Guorui Chen/Berkeley Lab)

    What’s thinner than a human hair but has a depth of special traits? A multitasking graphene device developed by researchers at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). The superthin material easily switches from a superconductor that conducts electricity without losing any energy, to an insulator that resists the flow of electric current, and back again to a superconductor – all with a simple flip of a switch. Their findings were reported today in the journal Nature.

    “Usually, when someone wants to study how electrons interact with each other in a superconducting quantum phase versus an insulating phase, they would need to look at different materials. With our system, you can study both the superconductivity phase and the insulating phase in one place,” said Guorui Chen, the study’s lead author and a postdoctoral researcher in the lab of Feng Wang, who led the study. Wang, a faculty scientist in Berkeley Lab’s Materials Sciences Division, is also a UC Berkeley physics professor.

    The graphene device is composed of three atomically thin (2D) layers of graphene sandwiched between 2D layers of boron nitride to form a repeating pattern called a moiré superlattice. The material could help other scientists understand the complicated mechanics behind a phenomenon known as high-temperature superconductivity, where a material can conduct electricity without resistance at temperatures higher than expected, though still hundreds of degrees below freezing.

    In a previous study [Nature], the researchers reported observing the properties of a Mott insulator in a device made of trilayer graphene. A Mott insulator is a class of material that somehow stops conducting electricity at hundreds of degrees below freezing despite classical theory predicting electrical conductivity. But it has long been believed that a Mott insulator can become superconductive by adding more electrons or positive charges to make it superconductive, Chen explained.

    For the past 10 years, scientists have been studying ways to combine different 2D materials, often starting with graphene – a material known for its ability to efficiently conduct heat and electricity. Out of this body of work, it was discovered that moiré superlattices formed with graphene exhibit exotic physics such as superconductivity when the layers are aligned at just the right angle.

    “So for this study we asked ourselves, ‘If our trilayer graphene system is a Mott insulator, could it also be a superconductor?’” said Chen.

    Opening the gate to a new world of physics

    2
    Two views of the trilayer graphene/boron nitride heterostructure device as seen through an optical microscope. The gold, nanofabricated electric contacts are shown in yellow; the silicon dioxide/silicon substrate is shown in brown; and the boron nitride flakes are shown in green. The trilayer graphene device is encapsulated between two boron nitride flakes. (Credit: Guorui Chen/Berkeley Lab)

    Working with David Goldhaber-Gordon of Stanford University and the Stanford Institute for Materials and Energy Sciences at SLAC National Accelerator Laboratory, and Yuanbo Zhang of Fudan University, the researchers used a dilution refrigerator, which can reach intensely cold temperatures of 40 millikelvins – or nearly minus 460 degrees Fahrenheit – to cool the graphene/boron nitride device down to a temperature at which the researchers expected superconductivity to appear near the Mott insulator phase, said Chen. (Goldhaber-Gordon is also

    Once the device reached a temperature of 4 kelvins (minus 452 degrees Fahrenheit), the researchers applied a range of electrical voltages to the tiny top and bottom gates of the device. As they expected, when they applied a high vertical electrical field to both the top and bottom gates, an electron filled each cell of the graphene/boron nitride device. This caused the electrons to stabilize and stay in place, and this “localization” of electrons turned the device into a Mott insulator.

    Then, they applied an even higher electrical voltage to the gates. To their delight, a second reading indicated that the electrons were no longer stable. Instead, they were shuttling about, moving from cell to cell, and conducting electricity without loss or resistance. In other words, the device had switched from the Mott insulator phase to the superconductor phase.

    Chen explained that the boron nitride moiré superlattice somehow increases the electron-electron interactions that take place when an electrical voltage is applied to the device, an effect that switches on its superconducting phase. It’s also reversible – when a lower electrical voltage is applied to the gates, the device switches back to an insulating state.

    The multitasking device offers scientists a tiny, versatile playground for studying the exquisite interplay between atoms and electrons in exotic new superconducting materials with potential use in quantum computers – computers that store and manipulate information in qubits, which are typically subatomic particles such as electrons or photons – as well as new Mott insulator materials that could one day make tiny 2D Mott transistors for microelectronics a reality.

    “This result was very exciting for us. We never imagined that the graphene/boron nitride device would do so well,” Chen said. “You can study almost everything with it, from single particles to superconductivity. It’s the best system I know of for studying new kinds of physics,” Chen said.

    This study was supported by the Center for Novel Pathways to Quantum Coherence in Materials (NPQC), an Energy Frontier Research Center led by Berkeley Lab and funded by the DOE Office of Science. NPQC brings together researchers at Berkeley Lab, Argonne National Laboratory, Columbia University, and UC Santa Barbara to study how quantum coherence underlies unexpected phenomena in new materials such as trilayer graphene, with an eye toward future uses in quantum information science and technology.

    Also contributing to the study were researchers from Shanghai Jiao Tong University and Nanjing University, China; the National Institute for Materials Science, Japan; and the University of Seoul, Korea.

    See the full article here .

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    Please help promote STEM in your local schools.

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    LBNL campus

    Bringing Science Solutions to the World
    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

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  • richardmitnick 12:16 pm on July 17, 2019 Permalink | Reply
    Tags: , Chemistry, Glass technology, , ,   

    From UCLA Newsroom: “UCLA researchers toughen glass using nanoparticles” 


    From UCLA Newsroom

    July 16, 2019
    Matthew Chin

    Process could be useful for applications in manufacturing and architecture.

    1
    An electron microscope image of a new, tougher glass developed at UCLA, showing how nanoparticles (rounded, irregular shapes) deflect a crack and force it to branch out. SciFacturing Lab/UCLA

    UCLA mechanical engineers and materials scientists have developed a process that uses nanoparticles to strengthen the atomic structure of glass. The result is a product that’s at least five times tougher than any glass currently available.

    The process could yield glass that’s useful for industrial applications — in engine components and tools that can withstand high temperatures, for instance — as well as for doors, tables and other architectural and design elements.

    The study was published online in the journal Advanced Materials and will be included in a future print edition. The authors wrote that same approach could also be used for manufacturing tougher ceramics that could be used, for example, in spacecraft components that are better able to withstand extreme heat.

    In materials science, “toughness” measures how much energy a material can absorb — and how much it can deform — without fracturing. While glass and ceramics can be reinforced using external treatments, like chemical coatings, those approaches don’t change the fact that the materials themselves are brittle.

    To solve that issue, the UCLA researchers took a cue from the atomic structure of metals, which can take a pounding and not break.

    “The chemical bonds that hold glass and ceramics together are pretty rigid, while the bonds in metals allow some flexibility,” said Xiaochun Li, the Raytheon Professor of Manufacturing at the UCLA Samueli School of Engineering, and the study’s principal investigator. “In glass and ceramics, when the impact is strong enough, a fracture will propagate quickly through the material in a mostly straight path.

    “When something impacts a metal, its more deformable chemical bonds act as shock absorbers and its atoms move around while still holding the structure together.”

    The researchers hypothesized that by infusing glass with nanoparticles of silicon carbide, a metal-like ceramic, the resulting material would be able to absorb more energy before it would fail. They added the nanoparticles into molten glass at 3,000 degrees Fahrenheit, which helped ensure that the nanoparticles were evenly dispersed.

    Once the material solidified, the embedded nanoparticles could act as roadblocks to potential fractures. When a fracture does occur, the tiny particles force it to branch out into tiny networks, instead of allowing it to take a straight path. That branching out enables the glass to absorb significantly more energy from a fracture before it causes significant damage.

    Sintering, in which a powder is heated under pressure, and then cooled, is the main method used to make glass. It also was the method used in previous experiments by other research groups to disperse nanoparticles in glass or ceramics. But in those experiments, the nanoparticles weren’t spread evenly, and the resulting material had uneven toughness.

    The glass blocks that the UCLA team developed for the experiment were somewhat milky, rather than clear, but Li said the process could be adapted to create clear glass.

    The other authors of the study are Qiang-Guo Jiang, a visiting scholar in Li’s SciFacturing Laboratory; Chezheng Cao and Ting-Chiang Lin, who received their doctorates from UCLA in 2018; and Shanghua Wu, an engineering professor at Guangdong University of Technology, China.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 11:56 am on July 12, 2019 Permalink | Reply
    Tags: "Enriching solid-state batteries", , Chemistry, Jennifer Rupp, , , , , ,   

    From MIT News: Women in STEM-“Enriching solid-state batteries” Jennifer Rupp 

    MIT News

    From MIT News

    July 11, 2019
    Denis Paiste | Materials Research Laboratory

    1
    MIT Associate Professor Jennifer Rupp stands in front of a pulsed laser deposition chamber, in which her team developed a new lithium garnet electrolyte material with the fastest reported ionic conductivity of its type. The technique produces a thin film about 330 nanometers thick. “Having the lithium electrolyte as a solid-state very fast conductor allows you to dream out loud of anything else you can do with fast lithium motion,” Rupp says. Photo: Denis Paiste/Materials Research Laboratory

    Researchers at MIT have come up with a new pulsed laser deposition technique to make thinner lithium electrolytes using less heat, promising faster charging and potentially higher-voltage solid-state lithium ion batteries.

    Key to the new technique for processing the solid-state battery electrolyte is alternating layers of the active electrolyte lithium garnet component (chemical formula, Li6.25Al0.25La3Zr2O12, or LLZO) with layers of lithium nitride (chemical formula Li3N). First, these layers are built up like a wafer cookie using a pulsed laser deposition process at about 300 degrees Celsius (572 degrees Fahrenheit). Then they are heated to 660 C and slowly cooled, a process known as annealing.

    During the annealing process, nearly all of the nitrogen atoms burn off into the atmosphere and the lithium atoms from the original nitride layers fuse into the lithium garnet, forming a single lithium-rich, ceramic thin film. The extra lithium content in the garnet film allows the material to retain the cubic structure needed for positively charged lithium ions (cations) to move quickly through the electrolyte. The findings were reported in a Nature Energy paper published online recently by MIT Associate Professor Jennifer L. M. Rupp and her students Reto Pfenninger, Michal M. Struzik, Inigo Garbayo, and collaborator Evelyn Stilp.

    “The really cool new thing is that we found a way to bring the lithium into the film at deposition by using lithium nitride as an internal lithiation source,” Rupp, the work’s senior author, says. Rupp holds joint MIT appointments in the departments of Materials Science and Engineering and Electrical Engineering and Computer Science.

    “The second trick to the story is that we use lithium nitride, which is close in bandgap to the laser that we use in the deposition, whereby we have a very fast transfer of the material, which is another key factor to not lose lithium to evaporation during a pulsed laser deposition,” Rupp explains.

    Safer technology

    Lithium batteries with commonly used electrolytes made by combining a liquid and a polymer can pose a fire risk when the liquid is exposed to air. Solid-state batteries are desirable because they replace the commonly used liquid polymer electrolytes in consumer lithium batteries with a solid material that is safer. “So we can kick that out, bring something safer in the battery, and decrease the electrolyte component in size by a factor of 100 by going from the polymer to the ceramic system,” Rupp explains.

    Although other methods to produce lithium-rich ceramic materials on larger pellets or tapes, heated using a process called sintering, can yield a dense microstructure that retains a high lithium concentration, they require higher heat and result in bulkier material. The new technique pioneered by Rupp and her students produces a thin film that is about 330 nanometers thick (less than 1.5 hundred-thousandths of an inch). “Having a thin film structure instead of a thick ceramic is attractive for battery electrolyte in general because it allows you to have more volume in the electrodes, where you want to have the active storage capacity. So the holy grail is be thin and be fast,” she says.

    Compared to the classic ceramic coffee mug, which under high magnification shows metal oxide particles with a grain size of tens to hundreds of microns, the lithium (garnet) oxide thin films processed using Rupp’s methods show nanometer scale grain structures that are one-thousandth to one-ten-thousandth the size. That means Rupp can engineer thinner electrolytes for batteries. “There is no need in a solid-state battery to have a large electrolyte,” she says.

    Faster ionic conduction

    Instead, what is needed is an electrolyte with faster conductivity. The unit of measurement for lithium ion conductivity is expressed in Siemens. The new multilayer deposition technique produces a lithium garnet (LLZO) material that shows the fastest ionic conductivity yet for a lithium-based electrolyte compound, about 2.9 x 10-5 Siemens (0.000029 Siemens) per centimeter. This ionic conductivity is competitive with solid-state lithium battery thin film electrolytes based on LIPON (lithium phosphorus oxynitride electrolytes) and adds a new film electrolyte material to the landscape.

    “Having the lithium electrolyte as a solid-state very fast conductor allows you to dream out loud of anything else you can do with fast lithium motion,” Rupp says.

    A battery’s negatively charged electrode stores power. The work points the way toward higher-voltage batteries based on lithium garnet electrolytes, both because its lower processing temperature opens the door to using materials for higher voltage cathodes that would be unstable at higher processing temperatures, and its smaller electrolyte size allows physically larger cathode volume in the same battery size.

    Co-authors Michal Struzik and Reto Pfenninger carried out processing and Raman spectroscopy measurements on the lithium garnet material. These measurements were key to showing the material’s fast conduction at room temperature, as well as understanding the evolution of its different structural phases.

    “One of the main challenges in understanding the development of the crystal structure in LLZO was to develop appropriate methodology. We have proposed a series of experiments to observe development of the crystal structure in the [LLZO] thin film from disordered or ‘amorphous’ phase to fully crystalline, highly conductive phase utilizing Raman spectroscopy upon thermal annealing under controlled atmospheric conditions,” says co-author Struzik, who was a postdoc working at ETH Zurich and MIT with Rupp’s group, and is now a professor at Warsaw University of Technology in Poland. “That allowed us to observe and understand how the crystal phases are developed and, as a consequence, the ionic conductivity improved,” he explains.

    Their work shows that during the annealing process, lithium garnet evolves from the amorphous phase in the initial multilayer processed at 300 C through progressively higher temperatures to a low conducting tetragonal phase in a temperature range from about 585 C to 630 C, and to the desired highly conducting cubic phase after annealing at 660 C. Notably, this temperature of 660 C to achieve the highly conducting phase in the multilayer approach is nearly 400 C lower than the 1,050 C needed to achieve it with prior sintering methods using pellets or tapes.

    “One of the greatest challenges facing the realization of solid-state batteries lies in the ability to fabricate such devices. It is tough to bring the manufacturing costs down to meet commercial targets that are competitive with today’s liquid-electrolyte-based lithium-ion batteries, and one of the main reasons is the need to use high temperatures to process the ceramic solid electrolytes,” says Professor Peter Bruce, the Wolfson Chair of the Department of Materials at Oxford University, who was not involved in this research.

    “This important paper reports a novel and imaginative approach to addressing this problem by reducing the processing temperature of garnet-based solid-state batteries by more than half — that is, by hundreds of degrees,” Bruce adds. “Normally, high temperatures are required to achieve sufficient solid-state diffusion to intermix the constituent atoms of ceramic electrolyte. By interleaving lithium layers in an elegant nanostructure the authors have overcome this barrier.”

    After demonstrating the novel processing and high conductivity of the lithium garnet electrode, the next step will be to test the material in an actual battery to explore how the material reacts with a battery cathode and how stable it is. “There is still a lot to come,” Rupp predicts.

    Understanding aluminum dopant sites

    A small fraction of aluminum is added to the lithium garnet formulation because aluminum is known to stabilize the highly conductive cubic phase in this high-temperature ceramic. The researchers complemented their Raman spectroscopy analysis with another technique, known as negative-ion time-of-flight secondary ion mass spectrometry (TOF-SIMS), which shows that the aluminum retains its position at what were originally the interfaces between the lithium nitride and lithium garnet layers before the heating step expelled the nitrogen and fused the material.

    “When you look at large-scale processing of pellets by sintering, then everywhere where you have a grain boundary, you will find close to it a higher concentration of aluminum. So we see a replica of that in our new processing, but on a smaller scale at the original interfaces,” Rupp says. “These little things are what adds up, also, not only to my excitement in engineering but my excitement as a scientist to understand phase formations, where that goes and what that does,” Rupp says.

    “Negative TOF-SIMS was indeed challenging to measure since it is more common in the field to perform this experiment with focus on positively charged ions,” explains Pfenninger, who worked at ETH Zurich and MIT with Rupp’s group. “However, for the case of the negatively charged nitrogen atoms we could only track it in this peculiar setup. The phase transformations in thin films of LLZO have so far not been investigated in temperature-dependent Raman spectroscopy — another insight towards the understanding thereof.”

    The paper’s other authors are Inigo Garbayo, who is now at CIC EnergiGUNE in Minano, Spain, and Evelyn Stilp, who was then with Empa, Swiss Federal Laboratories for Materials Science and Technology, in Dubendorf, Switzerland.

    Rupp began this research while serving as a professor of electrochemical materials at ETH Zurich (the Swiss Federal Institute of Technology) before she joined the MIT faculty in February 2017. MIT and ETH have jointly filed for two patents on the multi-layer lithium garnet/lithium nitride processing. This new processing method, which allows precise control of lithium concentration in the material, can also be applied to other lithium oxide films such as lithium titanate and lithium cobaltate that are used in battery electrodes. “That is something we invented. That’s new in ceramic processing,” Rupp says.

    “It is a smart idea to use Li3N as a lithium source during preparation of the garnet layers, as lithium loss is a critical issue during thin film preparation otherwise,” comments University Professor Jürgen Janek at Justus Liebig University Giessen in Germany. Janek, who was not involved in this research, adds that “the quality of the data and the analysis is convincing.”

    “This work is an exciting first step in preparing one of the best oxide-based solid electrolytes in an intermediate temperature range,” Janek says. “It will be interesting to see whether the intermediate temperature of about 600 degrees C is sufficient to avoid side reactions with the electrode materials.”

    Oxford Professor Bruce notes the novelty of the approach, adding “I’m not aware of similar nanostructured approaches to reduce diffusion lengths in solid-state synthesis.”

    “Although the paper describes specific application of the approach to the formation of lithium-rich and therefore highly conducting garnet solid electrolytes, the methodology has more general applicability, and therefore significant potential beyond the specific examples provided in the paper,” Bruce says. Commercialization may be needed to be demonstrate this approach at larger scale, he suggests.

    While the immediate impact of this work is likely to be on batteries, Rupp predicts another decade of exciting advances based on applications of her processing techniques to devices for neuromorphic computing, artificial intelligence, and fast gas sensors. “The moment the lithium is in a small solid-state film, you can use the fast motion to trigger other electrochemistry,” she says.

    Several companies have already expressed interest in using the new electrolyte approach. “It’s good for me to work with strong players in the field so they can push out the technology faster than anything I can do,” Rupp says.

    This work was funded by the MIT Lincoln Laboratory, the Thomas Lord Foundation, Competence Center Energy and Mobility, and Swiss Electrics.

    See the full article here .


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    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

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  • richardmitnick 11:35 am on July 12, 2019 Permalink | Reply
    Tags: "Optimizing the Growth of Coatings on Nanowire Catalysts", , Chemistry, , ,   

    From Brookhaven National Lab: “Optimizing the Growth of Coatings on Nanowire Catalysts” 

    From Brookhaven National Lab

    July 8, 2019
    Ariana Manglaviti
    amanglaviti@bnl.gov
    (631) 344-2347

    Peter Genzer,
    genzer@bnl.gov
    (631) 344-3174

    1
    (Sitting from front) Iradwikanari Waluyo, Mingzhao Liu, Dario Stacchiola, (standing from front) Mehmet Topsakal, Mark Hybertsen, Deyu Lu, and Eli Stavitski at the Inner-Shell Spectroscopy beamline of Brookhaven Lab’s National Synchrotron Light Source II (NSLS-II). The scientists performed x-ray absorption spectroscopy experiments at NSLS-II to characterize the chemical state of titanium dioxide (titania) coatings on zinc oxide nanowires. They chemically processed the nanowires to make the coatings—which boost the efficiency of the nanowires in catalyzing the water-splitting reaction that produces oxygen and hydrogen, a sustainable fuel—more likely to adhere. These characterization results were coupled with electron microscopy imaging and theoretical analyses to generate a model of the amorphous (noncrystal) atomic structure of titania.

    Scientists chemically treated the surface of wire-looking nanostructures made of zinc oxide to apply a uniform coating of titanium dioxide; these semiconducting nanowires could be used as high-activity catalysts for solar fuel production.

    Solar energy harvested by semiconductors—materials whose electrical resistance is in between that of regular metals and insulators—can trigger surface electrochemical reactions to generate clean and sustainable fuels such as hydrogen. Highly stable and active catalysts are needed to accelerate these reactions, especially to split water molecules into oxygen and hydrogen. Scientists have identified several strong light-absorbing semiconductors as potential catalysts; however, because of photocorrosion, many of these catalysts lose their activity for the water-splitting reaction. Light-induced corrosion, or photocorrosion, occurs when the catalyst itself undergoes chemical reactions (oxidation or reduction) via charge carriers (electrons and “holes,” or missing electrons) generated by light excitation. This degradation limits catalytic activity.

    Now, scientists from the Center for Functional Nanomaterials (CFN)—a U.S. Department of Energy (DOE) Office of Science User Facility at Brookhaven National Laboratory—have come up with a technique for optimizing the activity of one such catalyst: 500-nanometer-long but relatively thin (40 to 50 nanometers) wire-looking nanostructures, or nanowires, made of zinc oxide (ZnO). Their technique—described in a paper published online in Nano Letters on May 3—involves chemically treating the surface of the nanowires in such a way that they can be uniformly coated with an ultrathin (two to three nanometers thick) film of titanium dioxide (titania), which acts as both a catalyst and protective layer.

    The CFN-led research is a collaboration between Brookhaven Lab’s National Synchrotron Light Source II (NSLS-II)—another DOE Office of Science User Facility— and Computational Science Initiative (CSI); the Center for Computational Materials Science at the Naval Research Laboratory; and the Department of Materials Science and Chemical Engineering at Stony Brook University.

    “Nanowires are ideal catalyst structures because they have a large surface area for absorbing light, and ZnO is an earth-abundant material that strongly absorbs ultraviolet light and has high electron mobility,” said co-corresponding author and study lead Mingzhao Liu, a scientist in the CFN Interface Science and Catalysis Group. “However, by themselves, ZnO nanowires do not have high enough catalytic activity or stability for the water-splitting reaction. Uniformly coating them with ultrathin films of titania, another low-cost material that is chemically more stable and more active in promoting interfacial charge transfer, enhances these properties to boost reaction efficiency by 20 percent compared to pure ZnO nanowires.”

    3
    (Background) A false-colored scanning electron microscope image of zinc oxide (ZnO) nanowires coated with titanium dioxide, or titania (TiO2). On average, the nanowires are 10 times longer than they are wide. The white-dashed inset contains a high-resolution transmission electron microscope image that distinguishes between the ZnO core and titania shell. The black-dashed inset features a structural model of the amorphous titania shell, with the red circles corresponding to oxygen atoms and the green and blue polyhedra corresponding to undercoordinated and coordinated titanium atoms, respectively.

    To “wet” the surface of the nanowires for the titania coating, the scientists combined two surface processing methods: thermal annealing and low-pressure plasma sputtering. For the thermal annealing, they heated the nanowires in an oxygen environment to remove defects and contaminants; for the plasma sputtering, they bombarded the nanowires with energetic oxygen gas ions (plasma), which ejected oxygen atoms from the ZnO surface.

    “These treatments modify the surface chemistry of the nanowires in such a way that the titania coating is more likely to adhere during atomic layer deposition,” explained Liu. “In atomic layer deposition, different chemical precursors react with a material surface in a sequential manner to build thin films with one layer of atoms at a time.”

    The scientists imaged the nanowire-shell structures with transmission electron microscopes at the CFN, shining a beam of electrons through the sample and detecting the transmitted electrons. However, because the ultrathin titania layer is not crystalline, they needed to use other methods to decipher its “amorphous” structure. They performed x-ray absorption spectroscopy experiments at two NSLS-II beamlines: Inner-Shell Spectroscopy (ISS) and In situ and Operando Soft X-ray Spectroscopy (IOS).

    “The x-ray energies at the two beamlines are different, so the x-rays interact with different electronic levels in the titanium atoms,” said co-author Eli Stavitski, ISS beamline physicist. “The complementary absorption spectra generated through these experiments confirmed the highly amorphous structure of titania, with crystalline domains limited to a few nanometers. The results also gave us information about the valence (charge) state of the titanium atoms—how many electrons are in the outermost shell surrounding the nucleus—and the coordination sphere, or the number of nearest neighboring oxygen atoms.”

    Theorists and computational scientists on the team then determined the most likely atomic structure associated with these experimental spectra. In materials with crystalline structure, the arrangement of an atom and its neighbors is the same throughout the crystal. But amorphous structures lack this uniformity or long-range order.

    “We had to figure out the correct combination of structural configurations responsible for the amorphous nature of the material,” explained co-corresponding author Deyu Lu, a scientist in the CFN Theory and Computation Group. “First, we screened an existing structural database and identified more than 300 relevant local structures using data analytics tools previously developed by former CFN postdoc Mehmet Topsakal and CSI computational scientist Shinjae Yoo. We calculated the x-ray absorption spectra for each of these structures and selected 11 representative ones as basis functions to fit our experimental results. From this analysis, we determined the percentage of titanium atoms with a particular local coordination.”

    The analysis showed that about half of the titanium atoms were “undercoordinated.” In other words, these titanium atoms were surrounded by only four or five oxygen atoms, unlike the structures in most common forms of titania, which have six neighboring oxygen atoms.

    To validate the theoretical result, Lu and the other theorists—Mark Hybertsen, leader of the CFN Theory and Computation Group; CFN postdoc Sencer Selcuk; and former CFN postdoc John Lyons, now a physical scientist at the Naval Research Lab—created an atomic-scale model of the amorphous titania structure. They applied the computational technique of molecular dynamics to simulate the annealing process that produced the amorphous structure. With this model, they also computed the x-ray absorption spectrum of titania; their calculations confirmed that about 50 percent of the titanium atoms were undercoordinated.

    “These two independent methods gave us a consistent message about the local structure of titania,” said Lu.

    “Fully coordinated atoms are not very active because they cannot bind to the molecules they do chemistry with in reactions,” explained Stavitski. “To make catalysts more active, we need to reduce their coordination.”

    “Amorphous titania transport behavior is very different from bulk titania,” added Liu. “Amorphous titania can efficiently transport both holes and electrons as active charge carriers, which drive the water-splitting reaction. But to understand why, we need to know the key atomic-scale motifs.”

    To the best of their knowledge, the scientists are the first to study amorphous titania at such a fine scale.

    “To understand the structural evolution of titania on the atomic level, we needed scientists who know how to grow active materials, how to characterize these materials with the tools that exist at the CFN and NSLS-II, and how to make sense of the characterization results by leveraging theory tools,” said Stavitski.

    Next, the team will extend their approach of combining experimental and theoretical spectroscopy data analysis to materials relevant to quantum information science (QIS). The emerging field of QIS takes advantage of the quantum effects in physics, or the strange behaviors and interactions that happen at ultrasmall scales. They hope that CFN and NSLS-II users will make use of the approach in other research fields, such as energy storage.

    This research used resources of Brookhaven Lab’s Scientific Data and Computing Center (part of CSI) and the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility operated by Lawrence Berkeley National Laboratory. The computational studies were in part supported by a DOE Laboratory Directed Research and Development (LDRD) project and the Office of Naval Research through the Naval Research Laboratory’s Basic Research Program.

    See the full article here .


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    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
    i1

     
  • richardmitnick 8:27 am on July 12, 2019 Permalink | Reply
    Tags: , , Chemistry, dDAC-dynamic diamond anvil cell, , , ,   

    From Lawrence Livermore National Laboratory: “Under pressure: New device’s 1.6 billion atmospheres per second assists impact studies” 

    From Lawrence Livermore National Laboratory

    July 11, 2019

    Anne M Stark
    stark8@llnl.gov
    925-422-9799

    1
    The new dynamic diamond anvil cell (dDAC) at the Extreme Conditions Beamline (ECB) at DESY’s X-ray source PETRA III. Image courtesy of Hanns-Peter Liermann/DESY

    A new super-fast high-pressure device at DESY’s PETRA III X-ray light source allows scientists to simulate and study earthquakes and meteorite impacts more realistically in the lab.

    DESY Petra III

    The new-generation dynamic diamond anvil cell (dDAC), developed by scientists from Lawrence Livermore National Laboratory (LLNL), Deutsches Elektronen-Synchroton (DESY), the European Synchrotron Radiation Facility (ESRF) and the universities of Oxford, Bayreuth and Frankfurt/Main, compresses samples faster than any similar device before. The instrument can turn up the pressure at a record rate of 1.6 billion atmospheres per second and can be used for a wide range of dynamic high-pressure studies. The developers present their new device, that has already proved its capabilities in various materials experiments, in the journal Review of Scientific Instruments.

    “For more than half a century, the diamond anvil cell or DAC has been the primary tool to create static high pressures to study the physics and chemistry of materials under those extreme conditions — for example, to explore the physical properties of materials at the center of the Earth at 3.5 million atmospheres,” said lead author Zsolt Jenei from LLNL.

    To simulate fast dynamic processes like earthquakes and asteroid impacts more realistically with high compression rates in the lab, Jenei’s team, in collaboration with DESY scientists, developed a new generation of dynamically driven diamond anvil cell (dDAC), inspired by the pioneering original LLNL design, and coupled it with the new fast X-ray diffraction setup of the Extreme Conditions Beamline P02.2 at PETRA III.

    The new cell consists of two small modified brilliant diamonds that are pushed together by a powerful piezo electric drive. Thanks to improvements like the much stronger piezo actuators and fast, high peak current amplifiers, the new device is capable of rapidly compressing the tiny samples between the diamond anvils more than a thousand times faster than previous generation dynamic diamond anvil cells. “One unique aspect fo the dDAC technique is that it also allows us to characterize the response of a sample under well controlled fast decompression,” said co-author Earl O’Bannon from LLNL.

    To study the changes in physical properties of materials under high pressure, scientists shine X-rays on the small samples and record the way the X-rays are diffracted by the material. These diffraction patterns allow scientists to determine the structure of the material. However, to take snapshots of high-speed dynamic processes, the X-ray flash needs to be bright enough and the camera — the detector — must be fast enough.

    “For almost 10 years since the first invention of the dDAC at our Laboratory, it has been extremely difficult to conduct fast diffraction experiments because of the lack of photon flux and, more important, fast and highly sensitive high-energy X-ray diffraction detectors,” Jenei said. Only with the advent of the extremely bright third-generation X-ray sources, such as PETRA III, and the development of highly sensitive cameras, such as the gallium-arsenide (GaAs) Lambda detector, invented by the DESY detector group, did it become possible to collect diffraction images with the adequate short exposure times and temporal resolution.”

    The Extreme Conditions Beamline (ECB) at DESY has the world’s first two GaAs Lambda detectors. “By triggering them with a delay of 0.25 milliseconds, we are able to collect up to 4,000 frames per second,” said Hanns-Peter Liermann, the beamline scientist in charge of the ECB. The detectors were funded through a joint research project awarded by the German Federal Ministry of Education and Research BMBF to the Goethe University Frankfurt, where Björn Winkler is the principal investigator.

    Researchers working on the project have demonstrated the performance and versatility of the experimental setup with fast compression studies of heavy metals such as gold and bismuth, as well as light compounds such as ice (H2O) and planetary materials such as ferropericlase. While conducting fast diffraction experiments on gold, the team demonstrated an increase in pressure from 1,000 atmospheres to 1.4 million atmospheres in only 2.5 milliseconds (thousandth of a second), resulting in a maximum compression rate of 160 terapascals per second (a terapascal is a measure of pressure). During this extremely short time, the detectors collected eight diffraction patterns across the complete compression path.

    “We believe that with the existing setup we can improve the compression rates to maybe thousands of terapascals per second,” Liermann said. However, this will need even brighter X-ray flashes and still faster cameras such as the planned upgrade of PETRA III to a next-generation X-ray source PETRA IV and the High Energy Density experimental station (HED) at the European X-ray laser European XFEL, where DESY is participating in building a dDAC setup as part of the Helmholtz International Beamline for Extreme Fields (HIBEF) consortium.

    See the full article here .


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    Please help promote STEM in your local schools.

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    LLNL Campus

    Operated by Lawrence Livermore National Security, LLC, for the Department of Energy’s National Nuclear Security Administration
    Lawrence Livermore National Laboratory (LLNL) is an American federal research facility in Livermore, California, United States, founded by the University of California, Berkeley in 1952. A Federally Funded Research and Development Center (FFRDC), it is primarily funded by the U.S. Department of Energy (DOE) and managed and operated by Lawrence Livermore National Security, LLC (LLNS), a partnership of the University of California, Bechtel, BWX Technologies, AECOM, and Battelle Memorial Institute in affiliation with the Texas A&M University System. In 2012, the laboratory had the synthetic chemical element livermorium named after it.
    LLNL is self-described as “a premier research and development institution for science and technology applied to national security.” Its principal responsibility is ensuring the safety, security and reliability of the nation’s nuclear weapons through the application of advanced science, engineering and technology. The Laboratory also applies its special expertise and multidisciplinary capabilities to preventing the proliferation and use of weapons of mass destruction, bolstering homeland security and solving other nationally important problems, including energy and environmental security, basic science and economic competitiveness.

    The Laboratory is located on a one-square-mile (2.6 km2) site at the eastern edge of Livermore. It also operates a 7,000 acres (28 km2) remote experimental test site, called Site 300, situated about 15 miles (24 km) southeast of the main lab site. LLNL has an annual budget of about $1.5 billion and a staff of roughly 5,800 employees.

    LLNL was established in 1952 as the University of California Radiation Laboratory at Livermore, an offshoot of the existing UC Radiation Laboratory at Berkeley. It was intended to spur innovation and provide competition to the nuclear weapon design laboratory at Los Alamos in New Mexico, home of the Manhattan Project that developed the first atomic weapons. Edward Teller and Ernest Lawrence,[2] director of the Radiation Laboratory at Berkeley, are regarded as the co-founders of the Livermore facility.

    The new laboratory was sited at a former naval air station of World War II. It was already home to several UC Radiation Laboratory projects that were too large for its location in the Berkeley Hills above the UC campus, including one of the first experiments in the magnetic approach to confined thermonuclear reactions (i.e. fusion). About half an hour southeast of Berkeley, the Livermore site provided much greater security for classified projects than an urban university campus.

    Lawrence tapped 32-year-old Herbert York, a former graduate student of his, to run Livermore. Under York, the Lab had four main programs: Project Sherwood (the magnetic-fusion program), Project Whitney (the weapons-design program), diagnostic weapon experiments (both for the Los Alamos and Livermore laboratories), and a basic physics program. York and the new lab embraced the Lawrence “big science” approach, tackling challenging projects with physicists, chemists, engineers, and computational scientists working together in multidisciplinary teams. Lawrence died in August 1958 and shortly after, the university’s board of regents named both laboratories for him, as the Lawrence Radiation Laboratory.

    Historically, the Berkeley and Livermore laboratories have had very close relationships on research projects, business operations, and staff. The Livermore Lab was established initially as a branch of the Berkeley laboratory. The Livermore lab was not officially severed administratively from the Berkeley lab until 1971. To this day, in official planning documents and records, Lawrence Berkeley National Laboratory is designated as Site 100, Lawrence Livermore National Lab as Site 200, and LLNL’s remote test location as Site 300.[3]

    The laboratory was renamed Lawrence Livermore Laboratory (LLL) in 1971. On October 1, 2007 LLNS assumed management of LLNL from the University of California, which had exclusively managed and operated the Laboratory since its inception 55 years before. The laboratory was honored in 2012 by having the synthetic chemical element livermorium named after it. The LLNS takeover of the laboratory has been controversial. In May 2013, an Alameda County jury awarded over $2.7 million to five former laboratory employees who were among 430 employees LLNS laid off during 2008.[4] The jury found that LLNS breached a contractual obligation to terminate the employees only for “reasonable cause.”[5] The five plaintiffs also have pending age discrimination claims against LLNS, which will be heard by a different jury in a separate trial.[6] There are 125 co-plaintiffs awaiting trial on similar claims against LLNS.[7] The May 2008 layoff was the first layoff at the laboratory in nearly 40 years.[6]

    On March 14, 2011, the City of Livermore officially expanded the city’s boundaries to annex LLNL and move it within the city limits. The unanimous vote by the Livermore city council expanded Livermore’s southeastern boundaries to cover 15 land parcels covering 1,057 acres (4.28 km2) that comprise the LLNL site. The site was formerly an unincorporated area of Alameda County. The LLNL campus continues to be owned by the federal government.

    LLNL/NIF


    DOE Seal
    NNSA

     
  • richardmitnick 10:39 am on July 8, 2019 Permalink | Reply
    Tags: , Chemistry, , , The thickness of the tiny rectangular-shaped nanocrystals called nanoplatelets could be controlled with atomic precision., Tiny ‘greener’ nanocrystals that can be manipulated to produce high-quality pictures and lighting in electronic devices such as televisions.   

    From Curtin University: “Tiny nanocrystals create ‘brighter’ future for TV viewers, study finds” 

    From Curtin University

    8 July 2019

    Lucien Wilkinson
    Media Consultant
    Supporting Humanities and Science and Engineering
    Tel: +61 8 9266 9185
    Mob: +61 401 103 683
    lucien.wilkinson@curtin.edu.au

    Yasmine Phillips
    Media Relations Manager, Public Relations
    Tel: +61 8 9266 9085
    Mob: +61 401 103 877
    yasmine.phillips@curtin.edu.au

    Curtin University researchers have discovered tiny ‘greener’ nanocrystals that can be manipulated to produce high-quality pictures and lighting in electronic devices such as televisions.

    The research, published in the Journal of Physical Chemistry Letters, found that the thickness of the tiny rectangular-shaped nanocrystals, called nanoplatelets, could be controlled with atomic precision, and can be used to improve the brightness and colour performance displayed on an LCD screen.

    Lead researcher ARC DECRA Fellow Dr Guohua Jia, from Curtin’s School of Molecular and Life Sciences and the Curtin Institute for Functional Molecules and Interfaces, said manufacturers were constantly searching for products with unprecedented picture quality given the high demand and competition in the electronics industry.

    “A popular choice by consumers are quantum dot light emitting diodes (QLED) televisions, which use quantum dots to produce better brightness and a wider colour spectrum. The dots act like an activation layer when applied on a blue LED backlight, producing a more saturated and wider colour gamut,” Dr Jia said.

    “Our research explored whether we could improve the picture and lighting quality in similar electronic devices by creating a new form of nanocrystal. We were able to create these by using a wet-chemical, ‘bottom-up’ method, in which chemicals in their ionic phase react in a solvent in the presence of organic ligands such as amine.

    “Due to their unique shape and thickness, the nanocrystals produce colour that is much more pure. If they are used in electronic devices, they can greatly improve the lighting and picture quality by generating more vivid colours.”

    Dr Jia explained that the rectangular-shaped nanocrystals were non-toxic and ‘greener’ in comparison to other nanocrystals commonly used in similar devices and do not contain heavy-metal compounds.

    “The method that we invented can produce the nanocrystals in a large scale. This is valuable for industrial applications, as it can greatly improve the production of nanocrystals that can be used in electronic devices such as QLED televisions,” Dr Jia said.

    “The collaboration between several research groups around the world including Professor Chunsen Li from Chinese Academy of Sciences (CAS) and Dr Amit Sitt from Tel Aviv University in Israel, each with its unique capabilities and knowledge base, allowed us to tackle this unique problem both experimentally and theoretically, and may open the way for the development of new and exciting materials and technologies.

    “This research also underpinned a Patent Cooperation Treaty (PCT) application, and our team is looking for commercial and development partners to progress the commercialisation of this important research outcome.”

    The research was co-authored by researchers from the WA School of Mines: Minerals, Energy and Chemical Engineering at Curtin University, Chinese Academy of Sciences (CAS), The University of Western Australia and Tel Aviv University, in Israel.

    The research was funded by an Australian Research Council Discovery Early Career Researcher Award (ARC DECRA).

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Curtin University (formerly known as Curtin University of Technology and Western Australian Institute of Technology) is an Australian public research university based in Bentley and Perth, Western Australia. The university is named after the 14th Prime Minister of Australia, John Curtin, and is the largest university in Western Australia, with over 58,000 students (as of 2016).

    Curtin was conferred university status after legislation was passed by the Parliament of Western Australia in 1986. Since then, the university has been expanding its presence and has campuses in Singapore, Malaysia, Dubai and Mauritius. It has ties with 90 exchange universities in 20 countries. The University comprises five main faculties with over 95 specialists centres. The University formerly had a Sydney campus between 2005 & 2016. On 17 September 2015, Curtin University Council made a decision to close its Sydney campus by early 2017.

    Curtin University is a member of Australian Technology Network (ATN), and is active in research in a range of academic and practical fields, including Resources and Energy (e.g., petroleum gas), Information and Communication, Health, Ageing and Well-being (Public Health), Communities and Changing Environments, Growth and Prosperity and Creative Writing.

    It is the only Western Australian university to produce a PhD recipient of the AINSE gold medal, which is the highest recognition for PhD-level research excellence in Australia and New Zealand.

    Curtin has become active in research and partnerships overseas, particularly in mainland China. It is involved in a number of business, management, and research projects, particularly in supercomputing, where the university participates in a tri-continental array with nodes in Perth, Beijing, and Edinburgh. Western Australia has become an important exporter of minerals, petroleum and natural gas. The Chinese Premier Wen Jiabao visited the Woodside-funded hydrocarbon research facility during his visit to Australia in 2005.
    Contents

     
  • richardmitnick 10:07 am on July 4, 2019 Permalink | Reply
    Tags: , Chemistry, ,   

    From CSIROscope: “Lithium, the metal of the decade” 

    CSIRO bloc

    From CSIROscope

    3 July 2019
    Keirissa Lawson

    1
    As the demand for battery technologies grows so does the hunger for lithium commodities.

    Until your mobile phone runs flat, you probably don’t think about the battery technology inside.

    So what is powering your phone, your laptop, your tablet? It’s most likely a lithium ion battery.

    Recharging your batteries

    Lithium ion batteries are rechargeable, reliable and generally lighter than other rechargeable batteries.

    In recent years, our demand for personal electronics has also driven the demand for lithium. But it’s the development of low emission technologies, like electric vehicles and renewable energy, that’s really supercharging the market’s appetite for lithium commodities, worldwide.

    Australia is the world’s largest producer of lithium. That means we have an opportunity to be at the forefront of lithium production and to value-add across the mineral processing chain.

    From the stars to your smartphone

    Lithium is the third element in the periodic table. It’s also the lightest metal. In nature, lithium never exits in pure form. Instead, it forms compounds which are found in nearly all igneous rocks and in mineral springs.

    Where does it come from? Its origin goes back to the beginning of time (cue: dramatic classical music). Lithium was created in the Big Bang, along with hydrogen and helium. Stars are actually the super-factories of lithium, spreading the metal through the universe with every supernova.

    And this metal … well, it continues to bang! Because lithium is highly reactive. It’s a favourite ingredient in fireworks, exploding with a flare of crimson when ignited.

    2
    Red fire at night, reveller’s delight! Lithium is used to create bright red fireworks.

    Rock out: getting lithium from hard rock deposits

    Australia’s lithium resources are locked in hard rock deposits, such as highly crystallised igneous rock called pegmatites.

    Once they’re found, pegmatite deposits can be mined. Then ore is then processed: the rock is crushed to concentrate the lithium-bearing ore, called spodumene. Then it’s sold on overseas, for further processing.

    Given the increasing value of lithium, Australia can seize the opportunity to refine and add value to our lithium resources.

    Putting the (research) pedal to the (lithium) metal

    Given the importance of lithium as a global commodity, we’ve been researching all things lithium. We’ve been working on improving the technologies and techniques for mineral exploration, and improving the production of lithium metal.

    We’re working on discovering new lithium and critical metal deposits. We want to understand the metal-rich mineral systems in pegmatite fields, and identifying lithium-rich deposits.

    But we’re not just exploring new deposits. We’re also investigating ways to minimise mining impacts and helping producers make more efficient mining and processing decisions.

    Given next-generation batteries will likely require significant quantities of lithium metal, our innovations in metal production are also targeted towards lithium production. We’re developing a new extraction process, called LithSonic, that can be cleaner, more efficient, and lower-cost than the existing electrolysis process. Using supersonic flow, similar to the flow through a rocket engine, LithSonic can produce lithium metal powder directly by rapid cooling lithium vapour.

    For more information on these technologies and expertise, visit us at the CSIRO booth at the AusIMM Lithium conference in Perth, 3 to 4 July 2019.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia

    So what can we expect these new radio projects to discover? We have no idea, but history tells us that they are almost certain to deliver some major surprises.

    Making these new discoveries may not be so simple. Gone are the days when astronomers could just notice something odd as they browse their tables and graphs.

    Nowadays, astronomers are more likely to be distilling their answers from carefully-posed queries to databases containing petabytes of data. Human brains are just not up to the job of making unexpected discoveries in these circumstances, and instead we will need to develop “learning machines” to help us discover the unexpected.

    With the right tools and careful insight, who knows what we might find.

    CSIRO campus

    CSIRO, the Commonwealth Scientific and Industrial Research Organisation, is Australia’s national science agency and one of the largest and most diverse research agencies in the world.

     
  • richardmitnick 10:42 am on July 3, 2019 Permalink | Reply
    Tags: "Berkeley Lab Receives DOE Support for Building to Study Microbe-Ecosystem Interactions for Energy and Environmental Research", , BioEPIC, , Chemistry,   

    From Lawrence Berkeley National Lab: “Berkeley Lab Receives DOE Support for Building to Study Microbe-Ecosystem Interactions for Energy and Environmental Research” 

    Berkeley Logo

    From Lawrence Berkeley National Lab

    July 3, 2019

    1
    Research related to the Microbial Community Analysis and Functional Evaluation in Soils (mCAFES) project. (Credit: Marilyn Chung/Berkeley Lab)

    2
    Members of the Ecosystems and Networks Integrated with Genes and Molecular Assemblies (ENIGMA) research consortium at work. (Credit: Marilyn Chung/Berkeley Lab)

    3
    Soil sampling work conducted as part of the Terrestrial Ecosystems Science Scientific Focus Area (TES). (Credit: Roy Kaldschmidt/Berkeley Lab)

    Lawrence Berkeley National Laboratory (Berkeley Lab) recently received federal approval to proceed with preliminary design work for a state-of-the-art building that would revolutionize investigations into how interactions among microbes, water, soil, and plants shape entire ecosystems. Research performed in the building could help address many of today’s energy, water, and food challenges.

    BioEPIC (for Biological and Environmental Program Integration Center) would integrate pioneering research in the prediction of biological and environmental processes – from microbes to watersheds – now underway in the Lab’s Biosciences Area and Earth and Environmental Sciences Area. This includes the Ecosystems and Networks Integrated with Genes and Molecular Assemblies (ENIGMA) Scientific Focus Area, the Watershed Function Scientific Focus Area, the Terrestrial Ecosystems Science Scientific Focus Area (TES), and the Microbial Community Analysis and Functional Evaluation in Soils (m-CAFEs) project. These projects leverage innovative research at field sites around the country (ENIGMA, Watershed, TES) and in controlled, fabricated laboratory ecosystems (m-CAFEs). The projects are supported by the Office of Biological and Environmental Research (BER) within DOE’s Office of Science.

    BioEPIC is envisioned to enhance this existing research through a suite of next-generation research tools now being developed that would dramatically improve scientists’ ability to conduct carefully controlled experiments on soil-microbe-plant interactions. These tools would include instruments and computing infrastructure to virtually connect BioEPIC to relevant field sites, enabling the rapid transfer of insights discovered under laboratory conditions to the sites’ dynamic environments.

    One new research tool planned for BioEPIC would be an EcoPOD. About the size of a phone booth, EcoPODs are envisioned to allow scientists to study plants, microbes, soil, and air in a fully instrumented and contained miniature ecosystem.

    Another component proposed for BioEPIC would be a SMART (Sensors at Mesoscale for Autonomous Remote Telemetry) soils testbed, which would enable the exploration of soil-microbe-plant interactions under controlled yet “realistic” conditions that include soil and plant variability and hydrogeochemical gradients.

    At the other end of the environmental biology scale range, a new BER-funded cryo-electron microscopy resource in BioEPIC would enable researchers to interrogate microbial interactions at the atomic level.

    Co-locating these capabilities in one building would enable researchers to quantify how microbes influence the environment and how the environment influences microbial processes, across scales – from molecules to ecosystems, and from seconds to years. In addition to scientific discoveries, these new capabilities could lead to entirely new ways to harness microbes for game-changing solutions. Examples include more efficient methods for improving soil and water quality, enhanced terrestrial carbon storage, better drought-tolerance in crops, and higher-yield plant precursors for biofuels.

    “We are pleased that the Office of Biological and Environmental Research is entrusting us to develop the new capabilities needed to advance our understanding of these complex ecosystems, which will further our predictive understanding of biological-environmental processes across scales,” says Berkeley Lab Director Mike Witherell.

    The recent DOE approval, called Critical Decision 1, or CD-1, authorizes Berkeley Lab to begin preliminary architectural and engineering design work for BioEPIC, a proposed four-story, 72,000-square-foot laboratory and office building capable of housing approximately 200 scientists and visitors. BioEPIC is proposed to be located on a cleared lot that formerly held Berkeley Lab’s famed Bevatron particle accelerator. The building would be funded by the Office of Science’s Science Laboratories Infrastructure (SLI) Program.

    BioEPIC research would benefit from the five DOE Office of Science User Facilities now located at Berkeley Lab: the Advanced Light Source (ALS), Molecular Foundry, National Energy Research Scientific Computing Center (NERSC), Energy Sciences Network (ESnet), and Joint Genome Institute (JGI).

    See the full article here .

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    Stem Education Coalition

    Bringing Science Solutions to the World

    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

    University of California Seal

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  • richardmitnick 9:14 am on July 3, 2019 Permalink | Reply
    Tags: , , Cable bacteria grow to astonishing densities. One square inch of sediment may contain as much as eight miles of cables., Chemistry, Discoveries like these raised the possibility that other bacteria might be dabbling in electricity., Electroactive bacteria, Geobacter can also plug into other species of microbes., Geobacter metallireducens feeds on carbon compounds, Geobacter transfers its electrons to iron oxide or rust., , , The microbe responded by sprouting hairlike growths   

    From The New York Times: “Wired Bacteria Form Nature’s Power Grid: ‘We Have an Electric Planet’ “ 

    New York Times

    From The New York Times

    July 1, 2019
    Carl Zimmer

    Electroactive bacteria were running current through “wires” long before humans learned the trick.

    1
    Gordon Studer

    At three o’clock in the afternoon on September 4, 1882, the electrical age began. The Edison Illuminating Company switched on its Pearl Street power plant, and a network of copper wires came alive, delivering current to a few dozen buildings in the surrounding neighborhood.

    One of those buildings housed this newspaper. As night fell, reporters at The New York Times gloried in the steady illumination thrown off by Thomas Edison’s electric lamps. “The light was soft, mellow, and grateful to the eye, and it seemed almost like writing by daylight,” they reported in an article the following day.

    But nature invented the electrical grid first, it turns out. Even in 1882, thousands of miles of wires were already installed in the ground in the New York region — in meadows, in salt marshes, in muddy river bottoms. They were built by microbes, which used them to shuttle electricity.

    Electroactive bacteria were unknown to science until a couple of decades ago. But now that scientists know what to look for, they’re finding this natural electricity across much of the world, even on the ocean floor. It alters entire ecosystems, and may help control the chemistry of the Earth.
    What on Earth Is Going On?

    “Not to sound too crazy, but we have an electric planet,” said John Stolz, a microbiologist at Duquesne University in Pittsburgh.

    In the mid-1980s, Dr. Stolz was helping to study a baffling microbe fished out of the Potomac River by his colleague Derek Lovley. The microbe, Geobacter metallireducens, had a bizarre metabolism. “It took me six months to figure out how to grow it in the lab,” said Dr. Lovley, now a microbiologist at the University of Massachusetts at Amherst.

    Like us, Geobacter feed on carbon compounds. As our cells break down these compounds to generate energy, they strip off free electrons and transfer them to oxygen atoms, producing water molecules. Geobacter couldn’t use oxygen, however, because it lived at the bottom of the Potomac, where the element was in short supply.

    Instead, Geobacter transfers its electrons to iron oxide, or rust, Dr. Lovley and his colleagues discovered. The process helps turn rust into another iron compound, called magnetite.

    The finding left the scientists with a puzzle. We humans draw oxygen into our cells to utilize it, but Geobacter does not import rust. So the microbe must somehow get the electrons out of its cell body and attach them to rust particles. How?

    A real live wire

    The researchers struggled for years to find the answer. Dr. Stolz eventually turned to other microbes to study. But Dr. Lovley soldiered on. Over the years, he and his colleagues have come across Geobacter in many places far beyond the Potomac. They’ve even encountered the bacteria in oil drilled from deep underground. “It’s basically found everywhere,” Dr. Lovley said.

    In the early 2000s, Dr. Lovley’s team discovered that Geobacter could sense rust in its neighborhood. The microbe responded by sprouting hairlike growths.

    Maybe each of those growths, known as a pilus, was actually a wire that latched onto the rust, Dr. Lovley thought. Electrons could flow from the bacterium down the wire to the receptive rust. “It seemed like a wild idea at the time,” Dr. Lovley said.

    But he and his team found several clues suggesting that the pilus is indeed a living wire. In one experiment, when Geobacter was prevented from making pili, the bacteria couldn’t turn rust to magnetite. In another, Dr. Lovley and his colleagues plucked pili from the bacteria and touched them with an electrified probe. The current swiftly shot down the length of the hairs.

    Subsequent research revealed that Geobacter can deploy its wires in different ways to make a living. Not only can it plug directly into rust, it can also plug into other species of microbes.

    The partners of Geobacter welcome the incoming flow of electrons. They use the current to power their own chemical reactions, which convert carbon dioxide into methane.

    2
    Gordon Studer

    Discoveries like these raised the possibility that other bacteria might be dabbling in electricity. And in recent years, microbiologists have discovered a number of species that do.

    “When people are able to dig down at the molecular level, we’re finding major differences in strategy,” said Jeff Gralnick of the University of Minnesota. “Microbes have solved this issue in several different ways.”

    In the early 2000s, a Danish microbiologist named Lars Peter Nielsen discovered a very different way to build a microbial wire. He dug up some mud from the Bay of Aarhus and brought it to his lab. Putting probes in the mud, he observed the chemical reactions carried out by its microbes.

    “It developed in a very weird direction,” Dr. Nielsen recalled.

    At the base of the mud, Dr. Nielsen observed a buildup of a foul-smelling gas called hydrogen sulfide. That alone was not surprising — microbes in oxygen-free depths can produce huge amounts of hydrogen sulfide. Normally, the gas rises the surface, where oxygen-breathing bacteria can break most of it down.

    But the hydrogen sulfide in the Aarhus mud never made it to the surface. About an inch below the top of the mud, it disappeared; something was destroying it along the way.

    After weeks of perplexity, Dr. Nielsen woke up one night with an idea. If the bacteria at the bottom of the mud broke hydrogen sulfide without oxygen, they would build up extra electrons. This reaction could only take place if they could get rid of the electrons. Maybe they were delivering them to bacteria at the surface.

    “I imagined it could be electric wires, and I could explain all of this,” he said.

    So Dr. Nielsen and his colleagues looked for wires, and they found them. But the wires in the Aarhus mud were unlike anything previously discovered.

    Each wire runs vertically up through the mud, measuring up to two inches in length. And each one is made up of thousands of cells stacked on top of each other like a tower of coins. The cells build a protein sleeve around themselves that conducts electricity.

    As the bacteria at the bottom break down hydrogen sulfide, they release electrons, which flow upward along the “cable bacteria” to the surface. There, other bacteria — the same kind as on the bottom, but employing a different metabolic reaction — use the electrons to combine oxygen and hydrogen and make water.

    Cable bacteria are not unique to Aarhus, it turns out. Dr. Nielsen and other researchers have found them — at least six species so far — in many places around the world, including tidal pools, mud flats, fjords, salt marshes, mangroves and sea grass beds.

    And cable bacteria grow to astonishing densities. One square inch of sediment may contain as much as eight miles of cables. Dr. Nielsen eventually learned to spot cable bacteria with the naked eye. Their wires look like spider silk reflecting the sun.

    Electroactive microbes are so abundant, in fact, that researchers now suspect that they have a profound impact on the planet. The bioelectric currents may convert minerals from one form to another, for instance, fostering the growth of a diversity of other species. Some researchers have speculated that electroactive microbes may help regulate the chemistry of both the oceans and the atmosphere.

    “To me, it’s a strong reminder of how ready we are to ignore things we cannot imagine,” Dr. Nielsen said.

    Electroactive bacteria for hire

    Much about these microbes remains murky, and subject to debate. In April, Nikhil S. Malvankar, a physicist at Yale University, and his colleagues challenged Dr. Lovley’s finding that Geobacter use pili as wires.

    Their research indicates that bacteria use a different structure to pump electrons. It’s a wire built from building blocks called cytochromes. Individual cytochromes are important for moving electrons around inside cells. But until now no one knew they could be stacked into a conductive wire.

    “There never had been a material like this before,” Dr. Malvankar said.

    Sarah Glaven, a research biologist at the United States Naval Research Laboratory who was not involved in the new study, said she found it compelling. “Totally believe it,” she said. “The question is, is it just part of the puzzle?”

    It’s possible that Geobacter uses both structures to move electrons, Dr. Glaven said. Or maybe one serves a different function, and just happens to conduct electricity in the hands of a scientist.

    The answers to such questions matter deeply to scientists, who are tinkering with electroactive bacteria to develop new kinds of technology.

    At Cornell University, Buz Barstow and his colleagues are investigating the possibility of wiring bacteria to solar panels. The panels would capture sunlight and generate a stream of electrons. The electrons would stream down microbial wires to a species of bacteria called Shewanella, which would use the energy to convert sugar into fuel.

    It’s still a distant dream. For now, Dr. Barstow is trying to work out the basic biology by which Shewanella moves electrons from its wires to the molecules it uses for its metabolism. But he is so taken with the elegance of electroactive bacteria that he figures it’s worth a shot. “You’re talking to someone who has drunk the Kool-Aid,” he said.

    Other researchers are looking into using these filaments as sensors. For instance, a wristband with embedded wires might monitor people’s health by delivering electric current when it detects chemical changes in sweat. Dr. Lovley and his colleagues are genetically engineering Geobacter to add molecular hooks to their pili, so that they snag certain molecules.

    Among the many advantages that living wires may have is that they’d be easier on the environment than the man-made kind. “It takes a lot of energy and nasty chemicals to make a lot of those electronic materials, and then none of them are biodegradable,” Dr. Lovley said.

    Bacteria, by contrast, can build wires from little more than sugar. And when it comes time to throw wires away, they become food for other microbes.

    Dr. Nielsen, who now directs the Center for Electromicrobiology at the University of Aarhus in Denmark, said that he is avoiding the technology rush for now. There is still too much to learn about the microbes themselves. “Once we find out what these wires are made from and how they work, a lot of potential applications may show up,” he said.

    See the full article here .

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