#SynchroLightAt75 – APS lights the way to 2012 Chemistry Nobel

Thanks in part to research performed at the U.S. Department of Energy’s (DOE) Argonne National Laboratory, the 2012 Nobel Prize in Chemistry was awarded today to Americans Brian Kobilka and Robert Lefkowitz for their work on G-protein-coupled receptors.

G-protein-coupled receptors, or GPCRs, are a large family of proteins embedded in a cell’s membrane that sense molecules outside the cell and activate a cascade of different cellular processes in response. They constitute key components of how cells interact with their environments and are the target of nearly half of today’s pharmaceuticals.

These medicines work by connecting with many of the 800 or so human GPCRs. But to do this well, a drug needs to connect to the protein like a key opens a lock. Improving drugs requires knowing exactly how these proteins work and are structured, which is difficult because the long, slender protein chains are folded in an intricate pattern that threads in and out of the cell’s membrane.

In a study performed at Argonne in 2007, Kobilka, a professor at Stanford University, used intense X-rays produced by the laboratory’s Advanced Photon Source (APS) to make the first discovery of the structure of a human GPCR. This receptor, called the human β2 adrenoreceptor (β2AR), is responsible for a number of different biological responses, including facilitating breathing and dilating the arteries.

Read more on the Argonne National Laboratory website

Image: This is an image of a G-protein-coupled receptor signaling complex whose structure was identified in 2011. The receptor is in magenta while the different G protein subunits are colored green, red and blue. Stanford biochemist Brian Kobilka shared the 2012 Nobel Prize in Chemistry for his work in determining the structure of this activated GPCR using X-rays provided by Argonne’s Advanced Photon Source.

New insights of how the HIV-1 assembles and incorporates the Env protein

Assembly of HIV-1, which causes AIDS, takes place on the inner plasma membrane leaflet of infected cells, a geometric building process that creates hexamers out of trimers of the viral Gag protein, as guided by Gag’s N-terminal matrix domain.

Yet certain details of that virion assembly have been lacking for four decades. In a study published in the journal Proceedings of the National Academy of Sciences of the United States of America, Jamil Saad, Ph.D., University of Alabama at Birmingham (UAB), and colleagues provide the first atomic view of the matrix lattice, a step that advances the understanding of key mechanisms of viral assembly and viral envelope protein incorporation.

“Our findings may facilitate the development of new therapeutic agents that inhibit HIV-1 assembly, envelope incorporation and ultimately virus production,” said Saad, a professor of microbiology at UAB.

The Gag protein is post-translationally modified, in which a lipid-like myristate group is added to help Gag bind to the plasma membrane. How the myristoylated matrix domain, or myrMA, of Gag assembles into lattice eluded detection until now. 

Techniques with low molecular resolution — such as cryo-electron diffraction and cryo-electron tomography — suggested that the myrMA protein organizes as trimers, and these trimers then undergo higher-order organization to form hexamers of trimers. Saad’s study is consistent with a recent study, which suggested that the myrMA protein undergoes dramatic structural changes to allow the formation of distinct hexameric lattices in immature and mature viral particles. Virus maturation is the last step of the virus replication cycle, as the capsid core forms inside the assembled virus, yielding infectious particles.

The envelope protein of HIV-1, or Env, is a transmembrane protein delivered to the plasma membrane by the cell’s secretory pathway. The bulk of the Env protein extends beyond the membrane, but a tail hangs through the membrane back into the inside of the cell. Genetic and biochemical studies have suggested that incorporation of the viral Env protein into the virus particles also depends on interaction between the myrMA domain and the cytoplasmic tail of Env. In 2017, Saad’s lab solved the high-resolution structure of the cytoplasmic tail of Env, which was the last unknown protein structure of HIV-1.

Env is a key infectivity protein. As a mature HIV-1 virus approaches a target cell, Env attaches to proteins on the outside of the uninfected cell, and then the Env protein snaps like a mousetrap to fuse the viral membrane with the cell membrane. 

The structures described by Saad and UAB colleagues showing molecular details at 2.1- angstroms resolution were determined via x-ray diffraction data collected at the Southeast Regional Collaborative Access Team (SER-CAT) beamline 22-ID at the Advance Photon Source. The structures show that the myristic acid of myrMA plays a key role in stabilizing the lattice structure, so the ability to form crystals of myrMA was important. They achieved this elusive technical challenge by removing 20 amino acids from the end of the 132-amino acid myrMA. Formation of a Gag lattice on the plasma membrane is known to be obligatory for the assembly of immature HIV-1 and Env incorporation. 

Read more on the Argonne website

Image: X-ray crystallography revealed the structure of the HIV-1 matrix protein at 2.1 angstroms resolution, advancing understanding of key mechanisms of viral assembly.

Gerold Rosenbaum’s #My1stLight

From Gerold Rosenbaum – Advanced Photon Source user

A Playful Use of the Last 10 Minutes of a Run Turns Out to be Very Educational

In 1967, after finishing data collection on the DESY XUV beamline on the polarizer/polarization analyzer I had built for my diploma thesis, there were 15 minutes to go before the synchrotron was to be shut down. Since I always wanted to know how good the vacuum had to be for working in the XUV, I suggested to bleed up the 1-m-long sample chamber to 1/10000 atm or 0.08 torr. The playful use of the last 10 minutes of the run turned out to be an impressive demonstration of the superiority of the continuous spectrum of synchrotron radiation over other XUV sources (paired with a high-resolution monochromator). The very low intensity below 800 Å, even though at the peak of the monochromator spectrum, told me clearly where vacuum-UV starts.

Journal reference: R.P. Godwin, “Synchrotron radiation as a light source,” Springer-Verlag Tracts in Modern Physics 51, p.66, 1969.

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Understanding the structural implications of genetic mutations in heart-muscle disease

Cardiomyopathies are diseases of the heart muscle in which the muscle of the pumping chamber (ventricle) can become enlarged (dilated cardiomyopathy; DCM) or thickened (hypertrophic cardiomyopathy; HCM), potentially leading to heart failure. There are currently no effective treatments but the disease often has a genetic component related to mutations in the heart muscle proteins that are involved in muscle contraction, so some researchers have focused their therapeutic development efforts on correcting these muscle contraction problems based on the structural basis of the defect. A recent study from a team of researchers using the U.S. Department of Energy’s Advanced Photon Source (APS) employed humanized mouse models expressing mutations observed in patients with HCM and DCM to evaluate the structure-function relationships and the changes observed in cardiac muscle contraction with these mutations. The work, published in the Proceedings of the National Academy of Sciences of the United States of America, provides a deeper understanding of the effects of cardiomyopathy-causing gene mutations on heart muscle contraction that could lead to the development of new therapies for this potentially life-threatening disease.

About 70% of patients with inherited HCM have a defect in the gene for the cardiac myosin protein or the cardiac myosin binding protein C. However, recent genetic evidence has suggested that mutations in the cardiac regulatory light chain (RLC) MYL2 gene are more common than previously thought and can be associated with poor outcomes. In order to understand the structural basis for how mutations in the MYL2 gene can cause HCM, or the less commonly occurring DCM, the research team performed muscle structure and force measurement experiments on heart muscle samples from mice that express mutated human RLC proteins, the HCM-D166V mutation associated with hypertrophic cardiomyopathy or the DCM-D94A mutation associated with dilated cardiomyopathy.

Normally, the cardiac regulatory light chain protein acts as a major subunit of the cardiac myosin protein to regulate calcium-mediated interactions with other muscle proteins and the myosin movements that result in the power stroke of muscle contraction. On this basis, the team set out to understand the relationship between these two mutations in the MYL2 gene and associated defects in the function of RLC in cardiomyopathy.

They used the small-angle x-ray diffraction technique at the Biophysics Collaborative Access Team 18-ID x-ray beamline at the APS to compare the spatial orientation of the thick and thin muscle filaments in left ventricular papillary muscle (LVPM) from mice expressing the mutated human RLC to mice expressing the normal, unmutated wildtype human cardiac RLC. (The APS is an Office of Science user facility at Argonne National Laboratory.)

In this model system, small-angle x-ray diffraction can measure interfilament lattice spacing that is proportional to the distance between two adjacent muscle filaments and equatorial intensity ratios that provide information about the number of myosin heads that are attached to actin-containing thin filaments (cross-bridges). By comparing structural results at different concentrations of calcium and simultaneously recording force traces, they were able to get structure-function information for all three muscle types. The intensity ratios at different calcium concentrations showed that contraction of the HCM mutant muscles were the most sensitive to calcium, forming more cross-bridges at submaximal calcium concentrations than either the DCM mutant or the wildtype muscle.

Read more on the APS website

Image: Mechanism of action for HCM-D166V and DCM-D94A mutations. The HCM-D166V model disrupts the SRX state and promotes the SRX-to-DRX transition increasing the number of DRX heads and leading to hypercontractile behavior. The DCM-D94A model stabilizes the SRX state yielding fewer heads available for contraction and leading to clinical hypocontractility. Abbreviations: ELC, myosin essential light chain; RLC, regulatory light chain; DRX, disordered relaxed; SRX, super-relaxed.

How a soil microbe could rev up artificial photosynthesis

Researchers discover that a spot of molecular glue and a timely twist help a bacterial enzyme convert carbon dioxide into carbon compounds 20 times faster than plant enzymes do during photosynthesis. The results stand to accelerate progress toward converting carbon dioxide into a variety of products.

Plants rely on a process called carbon fixation – turning carbon dioxide from the air into carbon-rich biomolecules ­– for their very existence. That’s the whole point of photosynthesis, and a cornerstone of the vast interlocking system that cycles carbon through plants, animals, microbes and the atmosphere to sustain life on Earth. 

But the carbon fixing champs are not plants, but soil bacteria. Some bacterial enzymes carry out a key step in carbon fixation 20 times faster than plant enzymes do, and figuring out how they do this could help scientists develop forms of artificial photosynthesis to convert the greenhouse gas into fuels, fertilizers, antibiotics and other products.

Now a team of researchers from the Department of Energy’s SLAC National Accelerator Laboratory, Stanford University, Max Planck Institute for Terrestrial Microbiology in Germany, DOE’s Joint Genome Institute (JGI) and the University of Concepción in Chile has discovered how a bacterial enzyme – a molecular machine that facilitates chemical reactions – revs up to perform this feat.

Rather than grabbing carbon dioxide molecules and attaching them to biomolecules one at a time, they found, this enzyme consists of pairs of molecules that work in sync, like the hands of a juggler who simultaneously tosses and catches balls, to get the job done faster. One member of each enzyme pair opens wide to catch a set of reaction ingredients while the other closes over its captured ingredients and carries out the carbon-fixing reaction; then, they switch roles in a continual cycle.  

Read more on the SLAC website

Discovered: An easier way to create “Flexible Diamonds”

As hard as diamond and as flexible as plastic, highly sought-after diamond nanothreads would be poised to revolutionize our world—if they weren’t so difficult to make. A team of scientists led by Samuel Dunning and Timothy Strobel of the Carnegie Institution for Science using high-brightness x-rays from the U.S. Department of Energy’s (DOE’s) Advanced Photon Source developed an original technique that predicts and guides the ordered creation of strong, yet flexible, diamond nanothreads, surmounting several existing challenges.  The innovation will make it easier for scientists to synthesize the nanothreads—an important step toward applying the material to practical problems in the future. The work was published in the Journal of the American Chemical Society.

Diamond nanothreads are ultra-thin, one-dimensional carbon chains, tens of thousands of times thinner than a human hair. They are often created by compressing smaller carbon-based rings together to form the same type of bond that makes diamonds the hardest mineral on our planet. However, instead of the three-dimensional carbon lattice found in a normal diamond, the edges of these threads are “capped” with carbon-hydrogen bonds, which make the whole structure flexible.

Dunning explains: “Because the nanothreads only have these bonds in one direction, they can bend and flex in ways that normal diamonds can’t.”

Scientists predict that the unique properties of carbon nanothreads will have a range of useful applications from providing sci-fi-like scaffolding on space elevators to creating ultra-strong fabrics. However, scientists have had a hard time creating enough nanothread material to actually test their proposed superpowers.

Read more on the APS website

Image: The starting sample of pyridazine—a six atom ring made up of four carbons and two nitrogens—changes under pressure as diamond nanothread formation progresses. The first and last images show that there has been a permanent color change between the samples after thread formation. The images don’t show individual threads, but “bulk” samples of pyridazine during compression, each around 40 microns thick with a 180-micron diameter.

Credit: Samuel Dunning

Brilliant people working towards a common goal

It’s #LoveYourDataWeek so it’s fitting that this week’s #LightSourceSelfie features a data expert. Mathew Cherukara leads the Computational X-ray Science Group at the Advanced Photon Source (APS) at Argonne National Laboratory near Chicago.

Mathew, who is from Kerala in India, works with his colleagues to develop the computational tools, algorithms and machine learning models used to analyse data from the beamlines at the APS. The first time Mathew saw a light source he recalls, “I couldn’t believe that science on this scale was being done every single day”. Mathew also talks about the fact that, after the APS upgrade, the data rates and computational needs will increase 100 to 1,000 times. For Mathew, the best thing about working at a light source is all the brilliant people working towards a common goal. When Mathew isn’t working, he enjoys taking long walks with his dog and we’re treated to a very cute dog moment at the end of the video #LoveYourDog!

APS #LightSourceSelfie

Spare time hobbies and interests

Finding ways to relax and recharge your batteries is really important and helps you maintain perspective, particularly during very busy periods at work. Participants in #LightSourceSelfies told us what they like to do in their spare time. This montage, with contributors from the Australian Synchrotron, CHESS, SESAME and the APS, shows the variety of interests that people within the light source community have. If you are looking for a new way to relax and unwind, you might find an idea that appeals to you in this #LightSourceSelfie!

Enjoying your spare time away from light sources!

Developing new alloys for hydrogen fuel and catalysis

An alloy is a metal that contains two or three different elements. Steel, for instance, is an alloy of iron and carbon that offers increased strength as a building material.

By mixing more elements together, scientists hope to create new and improved alloys with increased strength and improved corrosion resistance, which could help many industry sectors to reduce costs.

“The trouble is that when you try to make a traditional alloy with more than a couple of elements, the elements tend to separate from each other and clump together,” said David Morris, a PhD student in the Department of Chemistry at the Dalhousie University.

That’s why his research team is interested in alloys with five or more elements that have a highly disordered nature. This chaotic property causes the elements to disperse throughout the mixture and prevent clumping. “You can get alloys with elements that wouldn’t usually go together,” he said.

Morris and his colleagues, including Liangbing Hu’s group from the University of Maryland who synthesized the samples using a special carbothermal shock method, are investigating two alloy samples, one made of five elements and another with fifteen.

“Early experiments suggested that the five-element alloy has high catalytic activity for ammonia decomposition, a process used to make hydrogen fuel, but they potentially have all kinds of applications,” he said.

The team gathered data at the Advanced Photon Source (APS) in Illinois, thanks to the facility’s partnership with the Canadian Light Source (CLS) at the University of Saskatchewan. Using synchrotron light, Morris could analyze each element in their samples separately and spot the differences in the structures of the two alloys.

The researchers discovered that the fifteen-element alloy had some elements that showed oxidation and the length of some of the bonds between them increased. These properties, however, were not found in the five-element alloy, indicating the properties of these special alloys are highly dependent on their compositions.

“Increased oxidation means they are less stable, which could potentially increase the activity for catalysis,” said Morris. “And unusual bond lengths can change the properties and maybe make a more promising catalytic pathway.”

The group’s next step will be to try and link the changes in structure seen in this experiment to the alloys’ catalytic activity. “If we are able to find certain structural properties that are associated with a high catalytic activity, that would allow us to design more effective catalysts in the future,” said Morris.

Read more on the CLS website

Image: APS

Blowing in the wind

Monitoring dust from legacy mine tailings to keep communities safe

Queen’s university researchers have studied dust blown from legacy mine tailings at the Giant Mine in Yellowknife, NWT and determined vital information to inform future remediation efforts.

Using the CLS@APS, the researchers were able to determine the chemical form of arsenic in dust particles sourced from the Giant Mine tailings which intermittently blow into nearby communities.

“The synchrotron is really useful for looking at dust because you have this really tiny micron scale beam that you can focus on individual dust particles and get really good data,” said Queen’s researcher Alex Bailey, who conducted the study as part of her Master’s.

Giant Mine is a decommissioned gold mine located 5 km North of Yellowknife that is currently being remediated. The main concern around this site is the existence of toxic-to-humans arsenic trioxide which was formed as a byproduct of ore processing in the 1950s and 60s. Arsenic trioxide had been previously found in local soils and lake sediments, and there was a concern from local residents that arsenic trioxide may be present in dust generated from surface tailings which intermittently blows into the community. It was important for the wellbeing and peace of mind of nearby community members to understand what dust from these tailings might carry.

By analyzing dust-sized material from the surface of the mine tailings and dust captured from a strategic location using detailed mineralogical analysis, synchrotron, and more conventional techniques, the team was able to identify what forms the arsenic would take and its implications for human health.

Read more on the CLS website

Image: Alex Bailey at the APS synchrotron collecting uXRD and uXRF data for sieved tailings dust samples

Promising new extra-large pore zeolite

An international research team, led in Spain by CSIC scientist Miguel A. Camblor, has discovered a stable aluminosilicate zeolite with a three dimensional system of interconnected extra-large pores, named ZEO-1.

Zeolites are crystalline porous materials with important industrial applications, including uses in catalytic processes. The pore apertures limit the access of molecules into and out of the inner confined space of zeolites, where reactions occur.

The research, published in Science, proved that ZEO-1 possesses these “extra-large” pores of around 10 Å (1 angstrom equals one ten billionth of a meter), but also smaller pores of around 7 Å, which is actually the size of traditional “large” pores.

Because of its porosity, strong acidity and high stability, ZEO-1 may find applications as a catalyst in fine chemistry for the production of pharmaceutical intermediates, in controlled substance release, for pollution abatement or as a support for the encapsulation of photo- or electroactive species (they react to light or an electric field).

“The crossings of its cages delimit super boxes, open spaces that can be considered nanoreactors to carry out chemical reactions in their confined space”, explains Miguel A. Camblor, researcher at the Instituto de Ciencia de Materiales de Madrid – CSIC.

To prove that this new zeolite may be useful in applications involving bigger molecules, researchers measured the adsorption to the inner surface of the zeolite of the dye Nile red – a big molecule. Moreover, they tested its performance in fluid catalytic cracking of heavy oil, a process the world still relies on to produce fuels. In both processes, the new zeolite performed better than the conventional large pore zeolite used nowadays.

This research is the result of an international collaboration between eight research centers in China, the USA, Sweden and Spain. The team was led by Fei-Jian Chen (Bengbu Medical College, China), Xiaobo Chen (China University of Petroleum), Jian Li (Stockholm University) and Miguel A. Camblor (Instituto de Ciencia de Materiales de Madrid, CSIC).

Structure determination with synchrotron light

The zeolite was discovered following a high-throughput screening methodology. The structure solution was challenging because the zeolite has a very complex structure, with a small crystal size (<200nm) but an exceedingly large cell volume.

“The combination of electron diffraction data with synchrotron powder X-ray diffraction data collected at the MSPD beamline of the ALBA Synchrotron and the Argonne National Laboratory (USA) made possible the accurate structure determination of ZEO-1″, says Camblor.

Read more on the ALBA website

Image: A perspective view of the extra-large pore of ZEO-1 along (100)

APS helps Pfizer create Covid-19 antiviral treatment

Pharmaceutical company Pfizer has announced the results of clinical trials of its new oral antiviral treatment against COVID-19. The new drug candidate, Paxlovid, proved to be effective against the SARS-CoV-2 virus, which causes COVID-19, according to results released by Pfizer on Nov. 5.

Scientists at Pfizer created Paxlovid with the help of the ultrabright X-rays of the Advanced Photon Source (APS), a U.S. Department of Energy (DOE) Office of Science user facility at DOE’s Argonne National Laboratory.

“Today’s news is a real game-changer in the global efforts to halt the devastation of this pandemic,” said Albert Bourla, chairman and chief executive officer of Pfizer, in a company press release. ​“These data suggest that our oral antiviral candidate, if approved or authorized by regulatory authorities, has the potential to save patients’ lives, reduce the severity of COVID-19 infections and eliminate up to nine out of 10 hospitalizations.”

DOE invests in user facilities such as the APS for the benefit of the nation’s scientific community, and supports biological research as part of its energy mission. This research has been critical in the fight against COVID-19. The DOE national laboratories formed the National Virtual Biotechnology Laboratory (NVBL) consortium in 2020 to combat COVID-19 using capabilities developed for their DOE mission, and that consortium helps support research into antiviral treatments such as Paxlovid.

Work to determine the structure of the antiviral candidate was done at the Industrial Macromolecular Crystallography Association Collaborative Access Team (IMCA-CAT) beamline at the APS, operated by the Hauptman-Woodward Medical Research Institute (HWI) on behalf of a collaboration of pharmaceutical companies, of which Pfizer is a member.

As a member of IMCA-CAT, Pfizer routinely conducts drug development experiments at the APS, and the process of narrowing down and zeroing in on this drug candidate was performed over many months, according to Lisa Keefe, executive director of IMCA-CAT and vice president for advancing therapeutics and principal scientist at Hauptman-Woodward Medical Research Institute. IMCA-CAT, she said, delivers quality results in a timely manner, much faster than the home laboratories of the companies themselves can do.

Read more on the APS website

Image: The IMCA-CAT beamline at the Advanced Photon Source, where work was done to determine the structure of Pfizer’s new COVID-19 antiviral treatment candidate.

Credit: Lisa Keefe, IMCA-CAT/Hauptman-Woodward Medical Research Institute

Laurent Chapon to lead Argonne’s Advanced Photon Source

Laurent Chapon has been appointed director of the Advanced Photon Source (APS). Chapon will lead the Photon Sciences Directorate at the U.S. Department of Energy’s Argonne National Laboratory through a massive upgrade of the user facility.

Lemont, IL – October 7, 2021 – The U.S. Department of Energy’s (DOE) Argonne National Laboratory has named Laurent Chapon as associate laboratory director for Photon Sciences and director of the Advanced Photon Source (APS), a DOE Office of Science User Facility at Argonne. He will begin his new role on January 10, 2022.

Chapon will join Argonne from Diamond Light Source in the United Kingdom, where he has been the director of physical sciences since 2016. Chapon led the scientific strategy in this division and oversaw five of Diamond’s eight science groups, which encompasses 22 X-ray beamlines and two electron microscopes. He led groups dedicated to technological advancements in optics, metrology and detectors technology at the facility and oversaw the Project Office, User Office, and Experiment Hall groups.

As part of Argonne’s senior management team, Chapon will lead the APS through a time of extraordinary change. The APS Upgrade project will result in a transformed facility that will generate X-ray beams up to 500 times brighter than those it currently delivers. This will require a year-long shutdown of the APS, currently scheduled to begin in April of 2023, and will keep the facility at the forefront of the world’s light sources for scientific discovery.

Read more on the Argonne National Laboratory website

Image: Laurent Chapon

Credit: Lise Chapon

Probing the Structure of a Promising NASICON Material

As physicists, materials scientists, and engineers continue striving to enhance and improve batteries and other energy storage technologies, a key focus is on finding or designing new ways to make electrodes and electrolytes.  One promising avenue of research involves solid-state materials, making possible batteries free of liquid electrolytes, which can pose fire and corrosion hazards.  An international group of researchers joined with scientists at Argonne National Laboratory to investigate the structure of crystalline and amorphous compounds based on the NASICON system, or sodium super-ion conductors. The work (using research carried out at the U.S. Department of Energy’s Advanced Photon Source [APS] and published in the Journal of Chemical Physics) reveals some substantial differences between the crystalline and glass phases of the NAGP system, which affect the ionic conductivity of the various materials.  The investigators note that the fraction of non-bridging oxygen (NBO) atoms appears to play a significant role, possibly altering the Na+ ion mobility, and suggest this as an area of further study.  The work provides fresh insights into the process of homogeneous nucleation and identifying superstructural units in glass ― a necessary step in engineering effective solid-state electrolytes with enhanced ionic conductivity. 

Because of their high ionic conductivity, materials with a NASICON structure are prime candidates for a solid electrolyte in sodium-ion batteries.  They can be prepared by a glass-ceramic route, which involves the crystallization of a precursor glass, giving them the usefulness of moldable bulk materials.  In this work, the research team specifically studied the NAGP system [Na1+xAlxGe2-x(PO4)3] with x = 0, 0.4 and 0.8 in both crystalline and glassy forms. Working at several different facilities, they used a combination of techniques, including neutron and x-ray diffraction, along with 27Al and 31P magic angle spinning and 31P/23Na double-resonance nuclear magnetic resonance spectroscopy.  The glassy form of NAGP materials was examined both in its as-prepared state and after thermal annealing, so that the changes on crystal nucleation could be studied.

Neutron powder diffraction measurements were performed at the BER II reactor source, Helmholtz-Zentrum Berlin, using the fine resolution powder diffractometer E9 (FIREPOD), followed by Rietveld analysis.  Further neutron diffraction observations were conducted at the Institut Laue-Langevin using the D4c diffractometer and at the ISIS pulsed neutron source using the GEM diffractometer.  X-ray diffraction studies were performed at X-ray Science Division Magnetic Materials Group’s beamline 6-ID-D of the APS, an Office of Science user facility at Argonne National Laboratory. 

Read more on the APS website

Image: Fig. 1. NASICON crystal structure showing the tetrahedral P(4) phosphate motifs (purple), octahedral GeO6 motifs (cyan) and Na+ ions (green). Oxygen atoms are depicted in red.

Researchers discover foam “Fizzics”

Chemical engineers at the University of Illinois Chicago and UCLA used the U.S. Department of Energy’s Advanced Photon Source (APS) in answering longstanding questions about the underlying processes that determine the life cycle of liquid foams. The breakthrough in understanding how liquid foams dissipate could help improve the commercial production and application of foams in a broad range of industries and could lead to improved products. Findings of the research were featured in the Proceedings of the National Academy of Sciences of the United States of America.

Foams are a familiar phenomenon in everyday lives — mixing soaps and detergents into water when doing dishes, blowing bubbles out of soapy water toys, sipping the foam off a cup of lattes or milk shake. Liquid foams can occur in a variety of natural and artificial settings. While some foams are produced naturally, as in bodies of water creating large ocean blooms on the beaches, others arise in industrial processes. In oil recovery and fermentation, for example, foams are a byproduct.

Whenever soapy water is agitated, foams are formed. They are mostly gas pockets separated by thin liquid films that often contain tiny molecular aggregates called micelles. Oily dirt, for example, is washed away by hiding in the water-phobic cores of micelles. In addition, fat digestion in our bodies relies on the role of micelles formed by bile salts.

Over time, foams dissipate as liquid within the thin films is squeezed out. Soap and detergent molecules that are by very nature amphiphilic (hydrophilic and hydrophobic) aggregate within water to form spherical micelles, with their outward-facing heads being hydrophilic and water-phobic tails forming the core.

Read more on the ANL website

Image: Micellar foam films show grayscale intensity variations that correspond to rich nanoscopic topography mapped using IDIOM protocols.

Credit: Chrystian Ochoa and Vivek Sharma/UIC

Tiny Chip-Based Device Performs Ultrafast Manipulation of X-Rays

Researchers from the U.S. Department of Energy’s Advanced Photon Source (APS) and Center for Nanoscale Materials at Argonne National Laboratory have developed and demonstrated new x-ray optics that can be used to harness extremely fast pulses in a package that is significantly smaller and lighter than conventional devices used to manipulate x-rays. The new optics are based on microscopic chip-based devices known as microelectromechanical systems (MEMS).

“Our new ultrafast optics-on-a-chip is poised to enable x-ray research and applications that could have a broad impact on understanding fast-evolving chemical, material and biological processes,” said research team leader Jin Wang from the X-ray Science Division Time Resolved Research (TRR) Group at the APS. “This could aid in the development of more efficient solar cells and batteries, advanced computer storage materials and devices, and more effective drugs for fighting diseases.”

In new results published in The Optical Society OSA) journal Optics Express, the researchers demonstrated their new x-ray optics-on-a-chip device (Fig. 1), which measures about 250 micrometers and weighs just 3 micrograms, using the TRR Group’s 7-ID-C x-ray beamline at the APS. The tiny device performed 100 to 1,000 times faster than conventional x-ray optics, which that tend to be bulky.

Read more on the APS website

Image: Fig. 1. The photograph shows two MEMS elements on a single chip (A), with the active elements of 250 µm × 250 µm, and the micrograph (B) highlighting the size of the diffractive element, as compared to a section of human hair (C).