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  • richardmitnick 8:27 pm on January 5, 2017 Permalink | Reply
    Tags: A New Way to See Proteins in Motion, , , EF-X (electric field-stimulated x-ray crystallography), X-ray images of proteins, X-ray Technology   

    From ANL APS: “A New Way to See Proteins in Motion” 

    ANL Lab

    News APS at Argonne National Laboratory

    01.03.2017
    No writer credit

    1
    A new technique to watch proteins in action involves applying large voltage pulses to protein crystals simultaneously with x-ray pulses, as shown in the photo (at left) of the experimental set-up in the BioCARS beamline at the APS. At right is a close-up view of a crystal sandwiched between electrodes that deliver the voltage.

    University of Texas Southwestern Medical Center researchers, in conjunction with colleagues from the University of Chicago, have developed a new imaging technique that makes x-ray images of proteins as they move in response to electric field pulses. The method could lead to new insights into how proteins work, said senior author Dr. Rama Ranganathan, of UT Southwestern. The technique had its first application in experiments at the U.S. Department of Energy Office of Science’s Advanced Photon Source (APS) at Argonne National Laboratory. The results were published in Nature.

    “Proteins carry out the basic reactions in cells that are necessary for life: They bind to other molecules, catalyze chemical reactions, and transmit signals within the cell,” said Ranganathan. “These actions come from their internal mechanics; that is, from the coordinated motions of the network of amino acids that make up the protein.”

    Often, Ranganathan said, the motions that underlie protein function are subtle and happen on time scales ranging from trillionths of a second to many seconds.

    “So far, we have had no direct way of ‘seeing’ the motions of amino acids over this range and with atomic precision, which has limited our ability to understand, engineer, and control proteins,” he said.

    The new method, which the researchers call EF-X (electric field-stimulated x-ray crystallography), is aimed at stimulating motions within proteins and visualizing those motions in real time at atomic resolution, he said. This approach makes it possible to create video-like images of proteins in action – a goal of future research, he explained.

    The method involves subjecting proteins to large electric fields of about 1 million volts per centimeter and simultaneously reading out the effects with x-ray crystallography, he said.

    The researchers’ EF-X experiments utilizing the BioCARS 14-ID x-ray beamline at the APS, which is an Office of Science user facility, showed proteins can sustain these intense electric fields, and further that the imaging method can expose the pattern of shape changes associated with a protein’s function. Additional standard crystallography data (in the absence of electric field) were collected at beamline 11-1, at Stanford Synchrotron Radiation Lightsource at the SLAC National Accelerator laboratory, also an Office of Science user facility.

    SLAC/SSRL
    SLAC/SSRL

    “This is not the first report of seeing atomic motions in proteins, but previous reports were specialized for particular proteins and particular kinds of motions,” said Ranganathan. “Our work is the first to open up the investigation to potentially all possible motions, and for any protein that can be crystallized. It changes what we can learn.”

    Ultimately, this work could explain how proteins work in both normal and disease states, with implications in protein engineering and drug discovery. An immediate goal is to make the method simple enough for other researchers to use, he added.

    “I think this work has opened a new door to understanding protein function. It is already capable of being used broadly for many very important problems in biology and medicine. But like any new method, there is room for many improvements that will come from both us and others. The first step will be to create a way for other scientists to use this method for themselves,” Ranganathan said.

    The group reports that they used the technique to study the PDZ domain of the human ubiquitin ligase protein LNX2, and found new information regarding how the protein actually works.

    See: Doeke R. Hekstra1‡, K. Ian White1, Michael A. Socolich1, Robert W. Henning2, Vukica Šrajer2, and Rama Ranganathan1*, Electric-field-stimulated protein Mechanics, Nature 540, 400 (15 December 2016). DOI: 10.1038/nature20571

    Author affiliations: 1. UT Southwestern Medical Center, 2. The University of Chicago ‡ Present address: Harvard University

    Correspondence: *rama.ranganathan@utsouthwestern.edu

    See the full article here .

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    Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science

    The Advanced Photon Source at Argonne National Laboratory is one of five national synchrotron radiation light sources supported by the U.S. Department of Energy’s Office of Science to carry out applied and basic research to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels, provide the foundations for new energy technologies, and support DOE missions in energy, environment, and national security.

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  • richardmitnick 9:23 am on December 15, 2016 Permalink | Reply
    Tags: , , , , , , X-ray crystallography, X-ray Technology   

    From Stanford: “Masters of Crystallization” 

    Stanford University Name
    Stanford University

    March 24, 2016 [Stanford just put this in social media 12.14.16.]
    Glennda Chui

    When molecules won’t crystallize and technology confounds, who you gonna call?

    1
    Macromolecular Structure Knowledge Center at Stanford’s Shriram Center. From left: Ted Li, T.J. Lane, MSKC Director Marc C. Deller, Nick Cox, Timothy Rhorer, Zachary Rosenthal.

    2
    Researcher Ted Li examines a sample tray full of protein crystals under a microscope. Photo: SLAC National Accelerator Laboratory.

    Biology isn’t just for biologists anymore. That’s nowhere more apparent than in the newly furnished lab in room 097 of the Shriram Center basement, where flasks of bacterial and animal cells, snug in their incubators, are churning out proteins destined for jobs they may not have done in nature.

    Researchers who use this lab span a broad range of backgrounds and interests: Chemists searching for novel antibiotics. Chemical engineers developing biofuels. Doctors seeking new treatments for diabetes.

    Most of these highly skilled researchers have one thing in common: They have no idea how to grow the proteins and other large biomolecules that are essential to their research or how to prepare those proteins for X-ray studies that will reveal their structure and function.

    That’s where Marc Deller comes in.

    “I’m the lab manager, scientist, lab cleaner — I do everything, and I help people who don’t know how to use the equipment,” says Deller, who arrived in August to establish and direct the Macromolecular Structure Knowledge Center (MSKC). “I’m pretty much unboxing things every day and trying to get things plugged in.”

    With a doctorate from Oxford and years of protein-wrangling experience, he’s here to help Stanford faculty and students grow, purify and crystallize proteins and other big biomolecules so they can be probed with the SSRL synchrotron or the LCLS X-ray laser at SLAC National Accelerator Laboratory, just up the hill.

    SLAC/SSRL
    SLAC SSRL Tunnel
    “SLAC/SSRL

    SLAC/LCLS
    SLAC/LCLS

    SLAC jointly funds the center with Stanford ChEM-H, an interdisciplinary institute aimed at understanding human biology at a chemical level, and the services offered at MSKC augment help available from the expert staff at the SLAC X-ray facilities.

    X-ray crystallography has been a revolutionary tool for understanding how living things work, revealing the structures of more than 100,000 proteins, nucleic acids and their complexes over the past few decades and fueling the development of numerous life-saving medications.

    But it’s not always easy, as chemistry graduate student Ted Li can attest. The protein he’s studying — a natural catalyst found in soil bacteria that scientists hope to turn into an antibiotic factory — “is very resistant to crystallization. It’s very floppy and doesn’t want to pack,” says Li, who works in the lab of Chaitan Khosla, professor of chemistry and of chemical engineering. “So I need to find a way to force them to do that. Most of the things I’m doing these days are completely new to me, and Marc is my main mentor. He’ll actually go with me to SLAC and guide me in how to collect my data.”

    In its first six months, MSKC has already helped scientists with two dozen research projects, and Deller is eager to round up more. “From my experience of doing this for 20 years,” he says, “making the protein is definitely a bottleneck.”

    See the full article here .

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    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

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  • richardmitnick 6:04 am on December 6, 2016 Permalink | Reply
    Tags: , Inorganic geochemistry, Molecular environmental science, , , X-ray Technology   

    From Stanford: “Eureka moment leads to new method of studying environmental toxins” 

    Stanford University Name
    Stanford University

    March 31, 2016 [Stanford just saw fit to put this in social media.]
    Ker Than

    1
    View of the TVA Kingston Fossil Plant fly ash spill. Work using X-ray beams is clarifying how pollutants bind or release from solid surfaces and move into groundwater. Photo: Brian Stansberry via Wikimedia Commons

    A technique for probing the surface of particles revealed how toxins move from the soil to groundwater.

    In 1986, Gordon Brown used SLAC’s Stanford Synchrotron Radiation Lightsource (SSRL) to visualize something no one had ever seen before: the exact way that atoms bond to a solid surface.

    SLAC/SSRL
    SLAC/SSRL

    The work stemmed from a eureka moment that Brown had during the doctoral defense of graduate student Kim Hayes but has since grown into one of the seminal works in inorganic geochemistry, and even spawned a new field of study — molecular environmental science.

    Knowing how charged ions interact with solid surfaces is crucial for understanding how toxic metal ions such as lead, arsenic and mercury or radioactive elements such as uranium may be released from particles in soils and sediments and into groundwater or vice versa. Using the techniques Brown’s team helped pioneer, scientists today can paint exquisitely detailed pictures of how metal ions bind to different solid surfaces, including those on nanoparticles.

    “You can determine what other atoms are around the pollutant ions of interest, the inter-atomic distances separating them and the number and types of chemical bonds that keep them bound to the surface,” says Brown, a professor of geological sciences and of photon science. “This is crucial for understanding how easily they move from one place to another.”


    Access mp4 video here .

    Synchrotron-generated X-rays like those produced at SSRL are ideal for this type of investigation for a number of reasons, says John Bargar, a senior scientist at SLAC and Brown’s former PhD student. For one thing, synchrotron X-rays are highly focused, much like laser beams. “All of the photons produced are condensed into either a pencil beam or a narrow fan,” Bargar says. “That means you can use nearly all of the photons that you’re making with very little waste.”

    Another advantage of synchrotron X-rays, Brown says, is that their extremely high intensity makes it possible to detect and study pollutant ions at the very low concentration levels typically found in many polluted environmental samples.

    Moreover, synchrotron X-rays are polarized, meaning their waves vibrate primarily in a single plane. By modifying the direction of polarization, scientists can create very powerful probes for studying chemical bonds in molecules.

    “A metal ion sitting inside a larger molecule is surrounded by many bonds. Oftentimes, we don’t want to interrogate all of those bonds at once,” Bargar says. “With polarized X-rays, we can selectively interrogate the bonds in a specific orientation.”

    Recently, Brown and Bargar have collaborated to study how organic matter and live microbial organisms affect the binding affinities of different environmental pollutants to solid surfaces. Bargar and Brown are also investigating ways to harness bacterial aggregations called biofilms to neutralize the effects of environmental pollutants. In addition, they are also using synchrotron X-rays at SSRL to look for more efficient ways of safely extracting oil and gas from tight shales via hydraulic fracturing, a process that is transforming the energy landscape of the United States.

    “The X-ray beams synchrotrons are able to generate today are about 15 orders of magnitude brighter than what was available when I was a graduate student. This has led to a revolution in all areas of science and engineering,” Brown says. “I could collect the data for my entire PhD thesis in one morning at SSRL now.”

    See the full article here .

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    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

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  • richardmitnick 7:48 am on November 4, 2016 Permalink | Reply
    Tags: , , , , , X-ray Technology   

    From SLAC: SLAC, Berkeley Lab Researchers Prepare for Scientific Computing on the Exascale” 


    SLAC Lab

    November 3, 2016

    1
    NERSC CRAY Cori supercomputer
    Development and testing of future exascale computing tools for X-ray laser data analysis and the simulation of plasma wakefield accelerators will be done on the Cori supercomputer at NERSC, the National Energy Research Scientific Computing Center at Lawrence Berkeley National Laboratory. (NERSC)

    Researchers at the Department of Energy’s SLAC National Accelerator Laboratory are playing key roles in two recently funded computing projects with the goal of developing cutting-edge scientific applications for future exascale supercomputers that can perform at least a billion billion computing operations per second – 50 to 100 times more than the most powerful supercomputers in the world today.

    The first project, led by SLAC, will develop computational tools to quickly sift through enormous piles of data produced by powerful X-ray lasers. The second project, led by DOE’s Lawrence Berkeley National Laboratory (Berkeley Lab), will reengineer simulation software for a potentially transformational new particle accelerator technology, called plasma wakefield acceleration.

    The projects, which will each receive $10 million over four years, are among 15 fully-funded application development proposals and seven proposals selected for seed funding by the DOE’s Exascale Computing Project (ECP). The ECP is part of President Obama’s National Strategic Computing Initiative and intends to maximize the benefits of high-performance computing for U.S. economic competiveness, national security and scientific discovery.

    “Many of our modern experiments generate enormous quantities of data,” says Alex Aiken, professor of computer science at Stanford University and director of the newly formed SLAC Computer Science division, who is involved in the X-ray laser project. “Exascale computing will create the capabilities to handle unprecedented data volumes and, at the same time, will allow us to solve new, more complex simulation problems.”

    Analyzing ‘Big Data’ from X-ray Lasers in Real Time

    X-ray lasers, such as SLAC’s Linac Coherent Light Source (LCLS) have been proven to be extremely powerful “microscopes” that are capable of glimpsing some of nature’s fastest and most fundamental processes on the atomic level.

    SLAC/LCLS
    SLAC/LCLS

    Researchers use LCLS, a DOE Office of Science User Facility, to create molecular movies, watch chemical bonds form and break, follow the path of electrons in materials and take 3-D snapshots of biological molecules that support the development of new drugs.

    At the same time X-ray lasers also generate giant amounts of data. A typical experiment at LCLS, which fires 120 flashes per second, fills up hundreds of thousands of gigabytes of disk space. Analyzing such a data volume in a short amount of time is already very challenging. And this situation is set to become dramatically harder: The next-generation LCLS-II X-ray laser will deliver 8,000 times more X-ray pulses per second, resulting in a similar increase in data volumes and data rates.

    SLAC/LCLS II schematic
    SLAC/LCLS II schematic

    Estimates are that the data flow will greatly exceed a trillion data ‘bits’ per second, and require hundreds of petabytes of online disk storage.

    As a result of the data flood even at today’s levels, researchers collecting data at X-ray lasers such as LCLS presently receive only very limited feedback regarding the quality of their data.

    “This is a real problem because you might only find out days or weeks after your experiment that you should have made certain changes,” says Berkeley Lab’s Peter Zwart, one of the collaborators on the exascale project, who will develop computer algorithms for X-ray imaging of single particles. “If we were able to look at our data on the fly, we could often do much better experiments.”

    Amedeo Perazzo, director of the LCLS Controls & Data Systems Division and principal investigator for this “ExaFEL” project, says, “We want to provide our users at LCLS, and in the future LCLS-II, with very fast feedback on their data so that can make important experimental decisions in almost real time. The idea is to send the data from LCLS via DOE’s broadband science network ESnet to NERSC, the National Energy Research Scientific Computing Center, where supercomputers will analyze the data and send the results back to us – all of that within just a few minutes.” NERSC and ESnet are DOE Office of Science User Facilities at Berkeley Lab.

    LBL NERSC Cray XC30 Edison supercomputer
    LBL NERSC Cray XC30 Edison supercomputer

    lcls-ii-image
    LCLS II

    X-ray data processing and analysis is quite an unusual task for supercomputers. “Traditionally these high-performance machines have mostly been used for complex simulations, such as climate modeling, rather than processing real-time data” Perazzo says. “So we’re breaking completely new ground with our project, and foresee a number of important future applications of the data processing techniques being developed.”

    This project is enabled by the investments underway at SLAC to prepare for LCLS-II, with the installation of new infrastructure capable of handling these enormous amounts of data.

    A number of partners will make additional crucial contributions.

    “At Berkeley Lab, we’ll be heavily involved in developing algorithms for specific use cases,” says James Sethian, a professor of mathematics at the University of California, Berkeley, and head of Berkeley Lab’s Mathematics Group and the Center for Advanced Mathematics for Energy Research Applications (CAMERA). “This includes work on two different sets of algorithms. The first set, developed by a team led by Nick Sauter, consists of well-established analysis programs that we’ll reconfigure for exascale computer architectures, whose larger computer power will allow us to do better, more complex physics. The other set is brand new software for emerging technologies such as single-particle imaging, which is being designed to allow scientists to study the atomic structure of single bacteria or viruses in their living state.”

    The “ExaFEL” project led by Perazzo will take advantage of Aiken’s newly formed Stanford/SLAC team, and will collaborate with researchers at Los Alamos National Laboratory to develop systems software that operates in a manner that optimizes its use of the architecture of the new exascale computers.

    “Supercomputers are very complicated, with millions of processors running in parallel,” Aiken says. “It’s a real computer science challenge to figure out how to use these new architectures most efficiently.”

    Finally, ESnet will provide the necessary networking capabilities to transfer data between the LCLS and supercomputing resources. Until exascale systems become available in the mid-2020s, the project will use NERSC’s Cori supercomputer for its developments and tests.

    esnet-map
    ESnet

    See the full article here .

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    SLAC Campus
    SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.
    i1

     
  • richardmitnick 9:03 am on October 14, 2016 Permalink | Reply
    Tags: Crystal Clear Imaging: Infrared Brings to Light Nanoscale Molecular Arrangement, CU Boulder STROBE for Science and Technology Center on Real-Time Functional Imaging, Infrared imaging, , , Scattering-type scanning near-field optical microscopy, X-ray Technology   

    From LBNL- “Crystal Clear Imaging: Infrared Brings to Light Nanoscale Molecular Arrangement” 

    Berkeley Logo

    Berkeley Lab

    October 13, 2016
    Glenn Roberts Jr.
    geroberts@lbl.gov
    510-486-5582

    1
    Infrared light (pink) produced by Berkeley Lab’s Advanced Light Source synchrotron (upper left) and a conventional laser (middle left) is combined and focused on the tip of an atomic force microscope (gray, lower right), where it is used to measure nanoscale details in a crystal sample (dark red). (Credit: Berkeley Lab, CU-Boulder)

    Detailing the molecular makeup of materials—from solar cells to organic light-emitting diodes (LEDs) and transistors, and medically important proteins—is not always a crystal-clear process.

    To understand how materials work at these microscopic scales, and to better design materials to improve their function, it is necessary to not only know all about their composition but also their molecular arrangement and microscopic imperfections.

    Now, a team of researchers working at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) has demonstrated infrared imaging of an organic semiconductor known for its electronics capabilities, revealing key nanoscale details about the nature of its crystal shapes and orientations, and defects that also affect its performance.

    To achieve this imaging breakthrough, researchers from Berkeley Lab’s Advanced Light Source (ALS) and the University of Colorado-Boulder (CU-Boulder) combined the power of infrared light from the ALS and infrared light from a laser with a tool known as an atomic force microscope.

    LBNL Advanced Light Source
    LBNL Advanced Light Source

    The ALS, a synchrotron, produces light in a range of wavelengths or “colors”—from infrared to X-rays—by accelerating electron beams near the speed of light around bends.

    The researchers focused both sources of infrared light onto the tip of the atomic force microscope, which works a bit like a record-player needle—it moves across the surface of a material and measures the subtlest of surface features as it lifts and dips.

    The technique, detailed in a recent edition of the journal Science Advances, allows researchers to tune the infrared light in on specific chemical bonds and their arrangement in a sample, show detailed crystal features, and explore the nanoscale chemical environment in samples.

    2
    This image shows the crystal shape and height of a material known as PTCDA, with height represented by the shading (white is taller, darker orange is lowest). The scale bar represents 500 nanometers. The illustration at bottom is a representation of the crystal shape. (Credit: Berkeley Lab, CU-Boulder)

    “Our technique is broadly applicable,” said Hans Bechtel an ALS scientist. “You could use this for many types of material—the only limitation is that it has to be relatively flat” so that the tip of the atomic force microscope can move across its peaks and valleys.

    Markus Raschke, a CU-Boulder professor who developed the imaging technique with Eric Muller, a postdoctoral researcher in his group, said, “If you know the molecular composition and orientation in these organic materials then you can optimize their properties in a much more straightforward way.

    “This work is informing materials design. The sensitivity of this technique is going from an average of millions of molecules to a few hundred, and the imaging resolution is going from the micron scale (millionths of an inch) to the nanoscale (billionths of an inch),” he said.

    The infrared light of the synchrotron provided the essential wide band of the infrared spectrum, which makes it sensitive to many different chemicals’ bonds at the same time and also provides the sample’s molecular orientation. The conventional infrared laser, with its high power yet narrow range of infrared light, meanwhile, allowed researchers to zoom in on specific bonds to obtain very detailed imaging.

    “Neither the ALS synchrotron nor the laser alone would have given us this level of microscopic insight,” Raschke said, while the combination of the two provided a powerful probe “greater than the sum of its parts.”

    Raschke a decade ago first explored synchrotron-based infrared nano-spectroscopy using the BESSY synchrotron in Berlin. With his help and that of ALS scientists Michael Martin and Bechtel, the ALS in 2014 became the first synchrotron to offer nanoscale infrared imaging to visiting scientists.

    The technique is particularly useful for the study and understanding of so-called “functional materials” that possess special photonic, electronic, or energy-conversion or energy-storage properties, he noted.

    In principle, he added, the new advance in determining molecular orientation could be adapted to biological studies of proteins. “Molecular orientation is critical in determining biological function,” Raschke said. The orientation of molecules determines how energy and charge flows across from cell membranes to molecular solar energy conversion materials.

    Bechtel said the infrared technique permits imaging resolution down to about 10-20 nanometers, which can resolve features up to 50,000 times smaller than a grain of sand.

    The imaging technique used in these experiments, known as “scattering-type scanning near-field optical microscopy,” or s-SNOM, essentially uses the atomic force microscope tip as an ultrasensitive antenna, which transmits and receives focused infrared light in the region of the tip. Scattered light, captured from the tip as it moves over the sample, is recorded by a detector to produce high-resolution images.

    “It’s non-invasive, and it provides information about molecular vibrations,” as the microscope’s tip moves over the sample, Bechtel said. Researchers used the technique to study the crystalline features of an organic semiconductor material known as PTCDA (perylenetetracarboxylic dianhydride).

    Researchers reported that they observed defects in the orientation of the material’s crystal structure that provide a new understanding of the crystals’ growth mechanism and could aid in the design molecular devices using this material.

    3
    Researchers measured the molecular orientation of crystals (light gray and white) in samples of a semiconductor material known as PTCDA. The scale bar is 500 nanometers. The colored dots correspond to the orientation of the crystals in the color bar to the left. The figures at far left show the tip of the atomic force microscope in relation to different crystal orientations. (Credit: Berkeley Lab, CU-Boulder)

    The new imaging capability sets the stage for a new National Science Foundation Center, announced in late September, that links CU-Boulder with Berkeley Lab, UC Berkeley, Florida International University, UC Irvine, and Fort Lewis College in Durango, Colo. The center will combine a range of microscopic imaging methods, including those that use electrons, X-rays, and light, across a broad range of disciplines.

    This center, dubbed STROBE for Science and Technology Center on Real-Time Functional Imaging, will be led by Margaret Murnane, a distinguished professor at CU-Boulder, with Raschke serving as a co-lead.

    At Berkeley Lab, STROBE will be served by a range of ALS capabilities, including the infrared beamlines managed by Bechtel and Martin and a new beamline dubbed COSMIC (for “coherent scattering and microscopy”). It will also benefit from Berkeley Lab-developed data analysis tools.

    Other contributors to the work include Benjamin Pollard and Peter van Blerkom, both members of Raschke’s group at CU-Boulder.

    The work was supported by the National Science Foundation. The ALS is a DOE Office of Science User Facility.

    See the full article here .

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  • richardmitnick 12:46 pm on October 3, 2016 Permalink | Reply
    Tags: ALS-U, , , , X-ray Technology   

    From LBNL: “Transformational X-ray Project Takes a Step Forward” 

    Berkeley Logo

    Berkeley Lab

    October 3, 2016
    Glenn Roberts Jr.
    geroberts@lbl.gov
    510-486-5582

    1
    A time-lapse view of the Advanced Light Source building at night. (Credit: Haris Mahic/Berkeley Lab)

    The U.S. Department of Energy (DOE) has confirmed the need for a unique source of X-ray light that would produce beams up to 1,000 times brighter than are now possible at Lawrence Berkeley National Laboratory’s (Berkeley Lab) Advanced Light Source (ALS), enabling new explorations of chemical reactions, battery performance, biological processes and exotic materials.

    LBNL/ALS
    LBNL/ALS

    The proposed Advanced Light Source Upgrade project, also known as ALS-U, has cleared the first step in the DOE approval process. On Sept. 27 it received “critical decision zero,” also known as CD-0, which approves the scientific need for the project. This initial step sets in motion a process of additional planning and reviews, and the laboratory will begin the upgrade’s conceptual design.

    1
    This rendering shows the existing equipment at Berkeley Lab’s Advanced Light Source (lower right) that forms the storage ring where accelerated electrons give off energy in the form of light. A planned upgrade, ALS-U (left and upper right), would replace this storage ring with a denser array of magnets, known as an MBA lattice, that would produce far brighter, steadier beams of so-called “soft” X-ray light. A unique secondary ring along the ALS’s inner wall, called an “accumulator” ring, would rapidly replenish the energy in the main ring. (Credit: Berkeley Lab)

    If ultimately advanced, the ALS-U would feature a new, circular array of powerful, compact magnets. This state-of-the-art array, known as a “multibend achromat (MBA) lattice,” and other improvements would allow the ALS to achieve far brighter, steadier beams of so-called “soft” or low-energy X-ray light to probe matter with unprecedented detail.

    MBA systems have been demonstrated successfully at a light source in Sweden known as MAX IV, and will be put to use in a planned upgrade to Argonne National Laboratory’s Advanced Photon Source [AS]facility in Illinois that specializes in a range of energies known as “hard” X-ray light that is complementary to the separate range of X-ray energies produced at the ALS.

    MAX IV Lund, Sweden
    MAX IV Lund, Sweden

    ANL APS
    ANL APS interior
    ANL/APS

    “This upgrade project is a very high priority for the laboratory and builds upon the lab’s long legacy of building and operating particle accelerators,” said Berkeley Lab Director Michael Witherell. “The ALS-U project will benefit from our expertise in many disciplines here, from engineering to accelerator and beam physics, and computer modeling and simulation.”

    Dave Robin, who is leading the ALS-U effort, said, “We’re excited by this development. ALS-U is designed to be the world’s brightest soft X-ray synchrotron light source. It will enable a generational leap, surpassing any soft X-ray storage-ring-based light source operating, under construction, or planned.”

    3
    The electron beam profile of Berkeley Lab’s Advanced Light Source today (left), compared to the brighter, highly focused beam (right) that is possible with an upgrade known as ALS-U. (Credit: Berkeley Lab).

    The present-day ALS is already a premier destination for thousands of scientists from around the nation and world each year to conduct soft X-ray experiments. Soft X-rays are particularly suited to studies of chemical, electronic, and magnetic properties of materials. The upgrade would deliver light to experiments in nearly continuous waves that are more uniform, or highly “coherent” and laser-like, which would allow scientists to resolve nanoscale properties in a range of samples and to observe real-time chemical processes and material functions.

    “ALS now is the world leader in science that utilizes soft X-rays. ALS-U will allow us to continue to lead the world in measuring and understanding new materials and chemical systems for the 21st century,” said Roger Falcone, ALS director. “With this brighter source, we can move from where we take high-resolution static images to making movies. We can look at things in finer detail and see how they are functioning in real time.”

    4
    The MERLIN X-ray beamline at Berkeley Lab’s Advanced Light Source, pictured here, specializes in studies of electronic structure in materials with exotic electronic and magnetic properties. (Credit: Roy Kaltschmidt/Berkeley Lab)

    In particular, the brighter, more coherent beams, which would approach the fundamental limits in performance for soft X-rays, will be useful for exploring materials at the nanoscale to map out their physical, chemical, and electronic structure as they evolve. Modern materials are complex and inherently varied, so their functionality can only be understood by measuring this non-uniformity in their properties.

    Scientists could use these beams to produce 3-D maps of battery and fuel cell chemistry at work, for example, which could ultimately provide clues to improving their performance.

    The brighter, more coherent, beams could also be used to explore exotic materials phenomena like superconductivity, in which materials can carry electrical current with nearly zero loss; and to study unusual quantum properties that are poorly understood and defy explanation by classical physics.

    The ALS is a synchrotron light source that can produce a wide spectrum of light, from infrared and ultraviolet light to X-rays. Synchrotrons accelerate electrons to nearly the speed of light, then direct them into curving paths that cause the electrons to give off some energy in the form of photons—fundamental particles of light. The electron storage ring at ALS is approximately 200 meters in circumference.

    ALS-U would utilize and preserve the existing ALS building, an iconic domed structure designed in the 1930s by Arthur Brown Jr., the architect who also designed Coit Tower, a San Francisco landmark.

    The upgrade would incorporate most of the 40 beamlines and supporting equipment that now allow simultaneous experiments across a wide range of scientific disciplines. Also, three new beamlines are planned that will be optimized for the new capabilities of ALS-U.

    5
    A panoramic view of the interior of the Advanced Light Source. (Credit: Roy Kaltschmidt/Berkeley Lab)

    About 200 scientific and engineering staff work at the ALS, which draws thousands of scientist “users” per year from around the world. In fiscal year 2015, the ALS hosted more than 2,500 of these visiting scientists from 43 U.S. states and Washington, D.C., and 33 other nations. In collaboration with ALS staff experts, these scientists produce more than 900 peer-reviewed articles per year featuring work performed at the ALS.

    “For over 20 years the ALS has grown in its number of users and the breadth of publications,” Falcone said. “This upgrade will ensure that in the next 20 years we will continue on that growth path, serving even more scientists and doing more science at emerging frontiers.”

    The ALS dome was originally built in the 1940s to house an early particle accelerator known as the 184-inch cyclotron, a brainchild of Berkeley Lab founder Ernest O. Lawrence. Construction to convert the facility into the ALS began in 1988 and was completed in 1993. The ALS has undergone several improvements since startup—the latest was a four-year brightness improvement project, completed in 2013 and which recently received the Energy Secretary’s Achievement Award, that as much as tripled the brightness of X-ray light at some of its beamlines.

    ALS-U represents the largest new project at the lab since the ALS was completed, and takes advantage of a more than half-billion-dollar investment in the existing ALS, said Robin. ALS-U could conceivably be up and running within a decade, he added. The next stage of DOE project review and approval, known as CD-1, would confirm site selection for the proposed transformational soft-X-ray synchrotron project.

    The Advanced Light Source is a DOE Office of Science User Facility.

    For more information about the ALS-U project, visit: http://als.lbl.gov/als-u/overview.

    See the full article here .

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  • richardmitnick 2:33 pm on September 26, 2016 Permalink | Reply
    Tags: , , , , , , , uperconducting part of the European XFEL accelerator ready, X-ray Technology   

    From European XFEL: “Superconducting part of the European XFEL accelerator ready” 

    XFEL bloc

    European XFEL

    26 September 2016
    No writer credit found

    Ninety-six modules fully installed in 1.7-km long tunnel section.

    An important milestone in the construction of the X-ray laser European XFEL has been reached: The 1.7-km long superconducting accelerator is installed in the tunnel. The linear accelerator will accelerate bunches of free electrons flying at near-light speed to the extremely high energy of 17.5 gigaelectronvolts. The bunches are accelerated in devices called resonators, which are cooled to a temperature of -271°C. In the next part of the facility, the electron bunches are used to generate the flashes of X-ray light that will allow scientists new insights into the nanocosmos. The European XFEL accelerator will be put into operation step by step in the next weeks. It will be the largest and most powerful linear accelerator of its type in the world. On 6 October, the German Minister for Education and Research, Prof. Johanna Wanka, and the Polish Vice Minister of Science and Education Dr Piotr Dardziński, will officially initiate the commissioning of the X-ray laser, including the accelerator. User operation at the European XFEL is anticipated to begin in mid-2017.

    Responsible for the construction of the accelerator was an international consortium of 17 research institutes under the leadership of Deutsches Elektronen-Synchrotron (DESY), which is also the largest shareholder of the European XFEL.

    DESY

    The central section consists of 96 accelerator modules, each 12 metres long, which contain almost 800 resonators made from ultrapure niobium surrounded by liquid helium. The electrons are accelerated inside of these resonators. The modules, which were industrially produced in cooperation with several partners, are on average about 16% more powerful than specified, so the original goal of 100 modules in the accelerator could be reduced to 96.

    1
    Using a small box as a clean area, technicians make connections between two accelerator modules in the European XFEL tunnel in April.
    Heiner Müller-Elsner / European XFEL

    “I congratulate the accelerator team for this milestone and thank all partners for their perseverance and their tireless efforts”, said the Chairman of the DESY Board of Directors Helmut Dosch. “The individual teams involved meshed like the gears of a clock to build the world’s most powerful and modern linear accelerator. That all was delivered within a tight budget deserves the utmost respect.”

    “We are excited that the installation of the accelerator modules has been successfully completed”, said European XFEL Managing Director and Chairman of the Management Board Massimo Altarelli. “This is an important step on the way to user operation next year. On this path there were numerous challenges that, in the past months and years, we faced together successfully. I thank DESY and our European partners for their enormous effort, and we look together with excitement towards the next weeks and months, when the accelerator goes into operation.”

    2
    The European XFEL accelerator tunnel. European XFEL

    The French project partner CEA in Saclay assembled the modules. Colleagues from the Polish partner institute IFJ-PAN in Kraków performed comprehensive tests of each individual module at DESY before it was installed in the 2-km long accelerator tunnel. Magnets for focusing and steering the electron beam inside the modules came from the Spanish research centre CIEMAT in Madrid. The niobium resonators were manufactured by companies in Germany and Italy, supervised by research centres DESY and INFN in Rome. Russian project partners such as the Efremov Institute in St. Petersburg and the Budker Institute in Novosibirsk delivered the different parts for vacuum components for the accelerator, within which the electron beam will be directed and focused in the non-superconducting portions of the facility at room temperature. Many other components were manufactured by DESY and their partners, including diagnostics and electron beam stabilization mechanisms, among others.

    In October, the accelerator is expected to move towards operation in several steps. As soon as the system for access control is installed, the interior of the modules can be slowly cooled to the operating temperature of two degrees above absolute zero—colder than outer space. Then DESY scientists can send the first electrons through the accelerator. At first, the electrons will be stopped in an “electron dump” at the end of the accelerator, until all of the beam properties are optimized. Then the electron beam will be sent further towards the X-ray light-generating magnetic structures called undulators. Here, the alternating poles of the undulator’s magnets will force the electron bunches to move in a tight, zigzagging “slalom” course for a 210-m stretch. In a self-amplifying intensification process, extremely short and bright X-ray flashes with laser-like properties will be generated. Reaching the conditions needed for this process is a massive technical challenge. Among other things, the electron bunches from the accelerator must meet precisely defined specifications. But the participating scientists have reason for optimism. All foundational principles and techniques have been proven at the free-electron laser FLASH at DESY, the prototype for the European XFEL. At European XFEL itself, the commissioning of the 30-m long injector has been complete since July. The injector generates the electron bunches for the main accelerator and accelerates them in an initial section to near-light speed.

    The beginning of user operation, the final step in the transition from the construction phase to the operation phase, is foreseen for summer 2017.

    See the full article here .

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    XFEL Campus

    The Hamburg area will soon boast a research facility of superlatives: The European XFEL will generate ultrashort X-ray flashes—27 000 times per second and with a brilliance that is a billion times higher than that of the best conventional X-ray radiation sources.

    The outstanding characteristics of the facility are unique worldwide. Starting in 2017, it will open up completely new research opportunities for scientists and industrial users.

     
  • richardmitnick 8:06 am on September 18, 2016 Permalink | Reply
    Tags: , , , X-ray Technology   

    From Science Alert: “Here’s how physicists accelerate particles to 99.99% the speed of light” 

    ScienceAlert

    Science Alert

    8

    Business Insider

    15 SEP 2016
    ALI SUNDERMIER

    1
    NSLS II. Brookhaven National Laboratory

    By now, you might be familiar with the concept of particle accelerators through the work of the Large Hadron Collider (LHC), the monstrous accelerator that enabled scientists to detect the Higgs boson.

    CERN/LHC Map
    CERN LHC Grand Tunnel
    CERN LHC particles
    LHC at CERN

    But the LHC is not alone – the world is equipped with more than 30,000 particle accelerators that are used for a seemingly endless variety of tasks.

    Some of these machines, like the LHC, accelerate particles to nearly the speed of light to smash them together and probe the fundamental building blocks of our universe. Others are used to seal milk cartons and bags of potato chips.

    Brookhaven National Laboratory in New York is home to one of the world’s most advanced particle accelerators: the National Synchrotron Light Source II (NSLS II).

    The NSLS II will allow researchers to do a wide range of science varying from developing better drug treatments, to building more advanced computer chips, to analysing everything from the molecules in your body to the soil you walk on.

    When scientists accelerate particles to these crazy speeds in the NSLS II, they force them to release energy which they can manipulate to do a mind-boggling array of different experiments.

    As electrons moving at nearly the speed of light go around turns, they lose energy in the form of radiation, such as X-rays. The X-rays produced at the NSLS II are extremely bright – a billion times brighter than the X-ray machine at your dentist’s office.

    When scientists focus this extremely bright light onto a very small spot, it allows them to probe matter at an atomic scale. It’s kind of like a microscope on steroids.

    Here’s how the NSLS II pushes particles to 99.99 percent the speed of light – all in the name of science.

    First, the electron gun generates electron beams and feeds them into the linear accelerator, or linac.

    In the linac, electromagnets and microwave radio-frequency fields are used to accelerate the electrons, which must travel in a vacuum to ensure they don’t bump into other particles and slow down.

    Next, the electrons enter a booster ring, where magnets and radio-frequency fields accelerate them to approximately 99.9 percent percent the speed of light.

    Then they are injected into a circular ring called a storage ring.

    3
    Ali Sundermier

    In the storage ring, the electrons are steered by an assortment of magnets.

    The blue magnets bend the motion of the electrons, the yellow magnets focus and defocus the path of the electrons, and the red and orange magnets take outlying electrons and bring them into a closer path.

    The smaller magnets are corrector magnets, which keep the beam in line.

    4
    Ali Sundermier

    This is an insertion device in the storage ring. Insertion devices are magnetic structures that wiggle the electron beam as it passes through the device. This produces an extremely bright and focused beam.

    5
    Ali Sundermier

    As the electrons go around turns in the storage ring, they decelerate slightly, losing energy.

    The lost energy can be converted into different forms of electromagnetic radiation, such as X-rays, that are directed down beamlines running in straight lines tangential to the storage ring.

    At the end of the beamline, the X-rays crash into samples of whatever material is the subject of the experiment.

    6
    Ali Sundermier

    This is an X-ray spectroscopy beamline, where scientists analyse the chemical composition of materials by exciting the electrons in an atom.

    7
    Ali Sundermier

    The circumference of the NSLS-II is so big, nearly half a mile, that many people working there travel around on tricycles.

    The NSLS II is still in the early stages of its development, having just taken over for its successor (the NSLS), in 2014. When it’s complete, it will be able to accommodate about 70 different beamlines.

    8
    Ali Sundermier

    This article was originally published by Business Insider.

    See the full article here .

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  • richardmitnick 11:15 am on September 9, 2016 Permalink | Reply
    Tags: , , Snapshots of molecules, X-ray Technology   

    From ANL: “Seeing energized light-active molecules proves quick work for Argonne scientists” 

    ANL Lab

    News from Argonne National Laboratory

    September 8, 2016
    Jared Sagoff

    For people who enjoy amusement parks, one of the most thrilling sensations comes at the top of a roller coaster, in the split second between the end of the climb and the rush of the descent. Trying to take a picture at exactly the moment that the roller coaster reaches its zenith can be difficult because the drop happens so suddenly.

    For chemists trying to take pictures of energized molecules, the dilemma is precisely the same, if not trickier. When certain molecules are excited – like a roller coaster poised at the very top of its run – they often stay in their new state for only an instant before “falling” into a lower energy state.

    1
    To understand how molecules undergo light-driven chemical transformations, scientists need to be able to follow the atoms and electrons within the energized molecule as it rides on the energy “roller coaster.”

    In a recent study, a team of researchers at the U.S. Department of Energy’s (DOE’s) Argonne National Laboratory, Northwestern University, the University of Washington and the Technical University of Denmark used the ultrafast high-intensity pulsed X-rays produced by the Linac Coherent Light Source (LCLS), a DOE Office of Science User Facility at SLAC National Accelerator Laboratory, to take molecular snapshots of these molecules.

    SLAC/LCLS
    SLAC/LCLS

    By using the LCLS, the researchers were able to capture atomic and electronic arrangements within the molecule that had lifetimes as short as 50 femtoseconds – which is about the amount of time it takes light to travel the width of a human hair.

    “We can see changes in these energized molecules which happen incredibly quickly,” said Lin Chen, an Argonne senior chemist and professor of chemistry at Northwestern University who led the research.

    Chen and her team looked the structure of a metalloporphyrin, a molecule similar to important building blocks for natural and artificial photosynthesis. Metalloporphyrins are of interest to scientists who seek to convert solar energy into fuel by splitting water to generate hydrogen or converting carbon dioxide into sugars or other types of fuels.

    Specifically, the research team examined how the metalloporphyrin changes after it is excited with a laser. They discovered an extremely short-lived “transient state” that lasted only a few hundred femtoseconds before the molecule relaxed into a lower energy state.

    “Although we had previously captured the molecular structure of a longer-lived state, the structure of this transient state eluded our detection because its lifetime was too short,” Chen said.

    When the laser pulse hits the molecule, an electron from the outer ring moves into the nickel metal center. This creates a charge imbalance, which in turn creates an instability within the whole molecule. In short order, another electron from the nickel migrates back to the outer ring, and the excited electron falls back into the lower open orbital to take its place.

    “This first state appears and disappears so quickly, but it’s imperative for the development of things like solar fuels,” Chen said. “Ideally, we want to find ways to make this state last longer to enable the subsequent chemical processes that may lead to catalysis, but just being able to see that it is there in the first place is important.”

    The challenge, Chen said, is to prolong the lifetime of the excited state through the design of the metalloporphyrin molecule. “From this study, we gained knowledge of which molecular structural element, such as bond length and planarity of the ring, can influence the excited state property,” Chen said. “With these results we might be able to design a system to allow us to harvest much of the energy in the excited state.”

    A paper based on the research, “Ultrafast excited state relaxation of a metalloporphyrin revealed by femtosecond X-ray absorption spectroscopy,” was published in the June 10 online edition of the Journal of the American Chemical Society.

    The research was funded by the DOE’s Office of Science and by the National Institute of Health.

    See the full article here .

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    Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America’s scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science. For more visit http://www.anl.gov.

    The Advanced Photon Source at Argonne National Laboratory is one of five national synchrotron radiation light sources supported by the U.S. Department of Energy’s Office of Science to carry out applied and basic research to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels, provide the foundations for new energy technologies, and support DOE missions in energy, environment, and national security. To learn more about the Office of Science X-ray user facilities, visit http://science.energy.gov/user-facilities/basic-energy-sciences/.

    Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science

    Argonne Lab Campus

     
  • richardmitnick 4:35 pm on August 31, 2016 Permalink | Reply
    Tags: , , X-ray Technology   

    From LBNL: “Researchers Peel Back Another Layer of Chemistry with ‘Tender’ X-rays” 

    Berkeley Logo

    Berkeley Lab

    August 31, 2016
    Glenn Roberts Jr.
    geroberts@lbl.gov
    510-486-5582

    1
    Berkeley Lab’s Ethan Crumlin, working with other researchers, found a new way to study chemical processes at work in batteries and in other chemical reactions using a specialized X-ray toolkit developed at the lab’s Advanced Light Source, an X-ray source. The technique was pioneered at the ALS’s Beam Line 9.3.1. (Credit: Marilyn Chung/Berkeley Lab)

    Scientists can now directly probe a previously hard-to-see layer of chemistry thanks to a unique X-ray toolkit developed at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). The X-ray tools and techniques could be extended, researchers say, to provide new insight about battery performance and corrosion, a wide range of chemical reactions, and even biological and environmental processes that rely on similar chemistry.

    In a first-of-its-kind experiment at Berkeley Lab’s Advanced Light Source [ALS], an X-ray source known as a synchrotron, researchers demonstrated this new, direct way to study the inner workings of an activity center in chemistry known as an “electrochemical double layer” that forms where liquids meets solids—where battery fluid (the electrolyte) meets an electrode, for example (batteries have two electrodes: an anode and a cathode).

    LBL Advanced Light Source
    ALS

    A key breakthrough enabling the latest experiment was in tailoring “tender” X-rays—which have an energy range tuned in a middle ground between the typical high-energy (or “hard”) and low-energy (or “soft”) X-rays used in research—to focus on chemistry within the double layer of a sample electrochemical system. The related study was published Aug. 31 in Nature Communications.

    Drilling down on the double layer

    In a battery, this electrochemical double layer describes the layer of charged atoms or molecules in the battery’s fluid that are drawn in and cling to the surface of the electrode because of their opposite electrical charge—an essential step in battery operation—and a second and closely related zone of chemical activity that is affected by the chemistry at the electrode’s surface. The complex molecular-scale dance of charge flow and transfer within a battery’s double layer is central to its function.

    2
    This stylized representation shows an electrochemical double layer, the heart of solid/liquid chemical interactions such as those occurring around a battery’s electrode. An experiment at Berkeley Lab used X-rays to study the properties of the double layer that formed as positively or negatively charged particles (ions, shown as plus and minus symbols) were drawn to a gold electrode (left). The experiment featured neutrally charged pyrazine molecules (dark blue) suspended in a water-based electrolyte, composed of potassium hydroxide. Researchers precisely measured changes in the charge properties of molecules caused by changes to the electric charge applied to the electrode and to the ion concentration of the electrolyte in the double-layer region. (Credit: Zosia Rostomian/Berkeley Lab)

    The latest work shows changes in the electric “potential” in this double layer. This potential is a location-based measure of the effect of an electric field on an object—an increased potential would be found in an electric charge moving toward a lightbulb, and flows to a lower potential after powering on the lightbulb.

    “To be able to directly probe any attribute of the double layer is a significant advancement,” said Ethan Crumlin, a research scientist at Berkeley Lab’s ALS who led the experiment. “Essentially, we now have a direct map, showing how potential within the double layer changes based on adjustments to the electrode charge and electrolyte concentration. Independent of a model, we can directly see this—it’s literally a picture of the system at that time.”

    He added, “This will help us with guidance of theoretical models as well as materials design and development of improved electrochemical, environmental, biological, and chemical systems.”

    New technique confronts decades-old problem

    Zahid Hussain, division deputy for scientific support at the ALS, who participated in the experiment, added, “The problem of understanding solid/liquid interfaces has been known for 50-plus years—everybody has been using simulations and modeling to try to conceive of what’s at work.” The latest work has narrowed the list of candidate models that explain what’s at work in the double layer.

    Hussain more than a decade ago had helped to pioneer X-ray tools and techniques at the ALS, which dozens of other research sites have since adopted, that allow researchers to study another important class of chemical reactions: those that occur between solids and gases.

    There was a clear need to create new study tools for solid/liquid reactions, too, he said. “Solid/liquid interfaces are key for all kinds of research, from batteries to fuel cells to artificial photosynthesis,” the latter which seeks to synthesize plants’ conversion of sunlight into energy.

    Hubert Gasteiger, a chemistry professor at the Technical University of Munich and the university’s chair of technical electrochemistry who is familiar with the latest experiment, said, “This work is already quite applicable to real problems,” as it provides new insight about the potential distribution within the double layer.

    “No one has been able to look into this roughly 10-nanometer-thin region of the electrochemical double layer in this way before,” he said. “This is one of the first papers where you have a probe of the potential distribution here. Using this tool to validate double-layer models I think would give us insight into many electrochemical systems that are of industrial relevance.”

    Probing active chemistry in changing conditions

    In the experiment, researchers from Berkeley Lab and Shanghai studied the active chemistry of a gold electrode and a water-containing electrolyte that also contained a neutrally charged molecule called pyrazine. They used a technique called ambient pressure X-ray photoelectron spectroscopy (APXPS) to measure the potential distribution for water and pyrazine molecules across the solid/liquid interface in response to changes in the electrode potential and the electrolyte concentration.

    3
    A view inside the experimental chamber used in a chemistry experiment at Berkeley Lab’s Advanced Light Source. Researchers used ‘tender’ X-rays to explore a nanometers-thick region known as the electrochemical double layer at ALS Beam Line 9.3.1. (Credit: Marilyn Chung)

    The experiment demonstrated a new, direct way to precisely measure a potential drop in the stored electrical energy within the double layer’s electrolyte solution. These measurements also allowed researchers to determine associated charge properties across the interface (known as the “potential of zero charge” or “pzc”).

    Upgrade, new beamline will enhance studies

    Importantly, the technique is well-suited to active chemistry, and there are plans to add new capabilities to make this technique more robust for studying finer details during the course of chemical reactions, and to bring in other complementary X-ray study techniques to add new details, Hussain said.

    An upgrade to the X-ray beamline where the experiment was conducted is now in progress and is expected to conclude early next year. Also, a brand new beamline that will marry this and several other X-ray capabilities for energy-related research, dubbed AMBER (Advanced Materials Beamline for Energy Research) is under construction at the ALS and is scheduled to begin operating in 2018.

    “What’s absolutely key to these new experiments is that they will be carried out in actual, operating conditions—in a working electrochemical cell,” Hussain said. “Ultimately, we will be able to understand how a material behaves down to the level of electrons and atoms, and also to understand charge-transfer and corrosion,” a key problem in battery longevity.

    Researchers from the Joint Center for Artificial Photosynthesis, the Joint Center for Energy Storage Research, the Gwangju Institute of Science and Technology in the Republic of Korea, the Shanghai Institute of Microsystem and Information Technology in China, and the School of Physical Science and Technology in China participated in this research. The work was supported by the U.S. Department of Energy Office Science, the National Natural Science Foundation of China, and the Chinese Academy of Sciences-Shanghai Science Research Center.

    The Advanced Light Source is a DOE Office of Science User Facility.

    See the full article here .

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