BNL Home
April 2019
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  1. NSLS-II Friday Lunchtime Seminar

    12 pm, NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    Many phenomena in soft matter physics and biology happen on microsecond timescales, e.g., folding kinetics of proteins, where the time scale is basically defined by the protein size. Despite of the importance of such processes, μs time scales are very difficult to access in X-ray scattering experiments at storage rings as well as in quasi-elastic neutron scattering. The time structure of the European XFEL with MHz pulse repetition rate in a bunch train enables for the first time structural studies of dynamics and kinetics at such time scales. A method to investigate such phenomena is X-ray photon correlation spectroscopy (XPCS), tracking changes of the coherent diffraction pattern, the so-called speckle pattern, over time. XPCS has become a well-established technique at modern storage ring sources studying timescales ranging from several 1000 s down to milliseconds. At FEL sources, the higher average flux and superior degree of coherence allow the access to shorter timescales down to femtoseconds using split-pulse techniques. On the other hand, sequential-pulse XPCS is limited by the repetition rate of the FEL pulses, i.e. about 8 to 50 ms at normal-conducting hard X-ray FEL sources such as LCLS (USA) and SACLA (Japan). The high repetition rate of the European XFEL enables dynamics measurement on sub-μs time scales, which is otherwise difficult to achieve at storage ring, neutron, pump-probe or lab-based experiments. In this talk, first dynamics measurements at FEL sources using correlation techniques will be introduced and recent results on prototypical soft matter samples as well as fs dynamics of liquid water will be discussed. Afterwards, results from our recent XPCS experiment at European XFEL will be discussed, where we successfully performed measurements of (sub-)µs dynamics of soft matter samples. Furthermore, special attention is paid on shot-to-shot and train-to-train fluctuations of coherence and beam pointing obtained by c

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  1. NSLS-II Colloquium

    4 pm, Large Seminar Room, Bldg. 510

    Hosted by: John Hill

    Scientists have advocated for the return of samples from Mars for decades. The quest has finally begun in earnest: the Jet Propulsion Laboratory is in the final stages of construction of the Mars 2020 mission. Mars 2020 builds on the highly successful design of the Mars Science Laboratory (Curiosity Rover) and is updated with new landing capabilities, scientific instruments, and a very sophisticated rock sample collection system. Mars 2020's chief goals are to unravel the geology of its landing site, seek evidence of potential Martian biosignatures, and prepare a cache of several dozen samples for possible return to Earth by a future element of a notional Mars Sample Return campaign. NASA recently selected the mission's destination: Jezero Crater. This crater once held a very deep lake comparable in size to Lake Tahoe. Key geologic targets at the site include ancient Martian bedrock, lake sediments and especially a remarkably preserved river delta, and unusual carbonate-bearing rocks possibly precipitated from lake-water. Mars 2020 will launch in the summer of 2020, land on February 18, 2021, and rove the surface for at least two years. I am Project Scientist for Mars 2020 and will describe the goals and development of this mission, and of Mars sample return.

12

There are no conferences scheduled at this time.

  1. NSLS-II Friday Lunchtime Seminar

    12 pm, NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    by K. Gofron, M. Rolland, J. Wlodek, The series of brief talks that concentrate on EPICS controls 1. Wireless sensors controlled from EPICS 2. Improvements to Area Detector at NSLS2 A. Low Energy, Low Cost: The Nordic Thingy:52 Sensor Suite 1. Wireless technologies 2. EPICS controls of wireless sensors 3. ioc components 4. Integrated into CSS, and clients B. Improvements to Area Detector deployment and features at NSLS2 1. ADPluginBar/Dmtx – QR Code and data matrix code readers for EPICS Area Detector 2. ADLambda – Adding new features to an existing driver, and updating to build on newer OS 3. ADCompVision – Bringing Computer Vision to Area Detector 4. ADUVC – An area detector driver for USB Video Class devices 5. ADEmergentVision – An area detector driver for Emergent Vision Technologies 10 GigE and 25 GigE cameras

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  1. APR

    26

    Friday

    NSLS-II Friday Lunchtime Seminar

    12 pm, NSLS-II Bldg. 743 Room 156

    Friday, April 26, 2019, 12:00 pm

    Hosted by: Ignace Jarrige

    Vacuum deposition of C60 on a graphene-coated surface is investigated with X-ray Photon Correlation Spectroscopy in surface-sensitive conditions. Local step-flow is observed through the observation of oscillatory correlations in the later stages of growth after crystalline mounds have formed. An important aspect of the work is that coherent X-rays do not average over complex structures, and this allows us to monitor the growth on polycrystalline surfaces without loss of information. The experimental results show that the step-flow velocity must be nonuniform, and we model the velocity of each step-edge as being a simple function of the lengths of the terraces above and below it. This model predicts that the steps become almost stationary near the edges of the mounds where the local terrace length is very small, and the average slope of the surface is large. It was not previously known that such nonuniform and disordered step arrays as we have observed would follow such a simple growth law. This work shows that the use of coherent X-ray scattering provides an approach to better understand surface dynamics and fluctuations during crystal growth.

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  1. APR

    26

    Friday

    NSLS-II Friday Lunchtime Seminar

    "Coherent X-ray measurement of local step-flow propagation during growth of polycrystalline organic semiconductor thin films"

    Presented by Randall Headrick, University of Vermont

    12 pm, NSLS-II Bldg. 743 Room 156

    Friday, April 26, 2019, 12:00 pm

    Hosted by: Ignace Jarrige

    Vacuum deposition of C60 on a graphene-coated surface is investigated with X-ray Photon Correlation Spectroscopy in surface-sensitive conditions. Local step-flow is observed through the observation of oscillatory correlations in the later stages of growth after crystalline mounds have formed. An important aspect of the work is that coherent X-rays do not average over complex structures, and this allows us to monitor the growth on polycrystalline surfaces without loss of information. The experimental results show that the step-flow velocity must be nonuniform, and we model the velocity of each step-edge as being a simple function of the lengths of the terraces above and below it. This model predicts that the steps become almost stationary near the edges of the mounds where the local terrace length is very small, and the average slope of the surface is large. It was not previously known that such nonuniform and disordered step arrays as we have observed would follow such a simple growth law. This work shows that the use of coherent X-ray scattering provides an approach to better understand surface dynamics and fluctuations during crystal growth.

  2. SEP

    12

    Thursday

    NSLS-II Colloquium

    "Theoretical Understanding of Photon Spectroscopies in Correlated Materials In and Out of Equilibrium"

    Presented by Thomas Devereaux, SLAC

    4 pm, Large Seminar Room, Bldg. 510

    Thursday, September 12, 2019, 4:00 pm

    Hosted by: John Hill

    Pending

  1. NSLS-II Friday Lunchtime Seminar

    "Wireless Sensors, and updates to areaDetector with Computer Vision"

    Presented by Kazimierz Gofron, NSLS-II

    Friday, April 12, 2019, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    by K. Gofron, M. Rolland, J. Wlodek, The series of brief talks that concentrate on EPICS controls 1. Wireless sensors controlled from EPICS 2. Improvements to Area Detector at NSLS2 A. Low Energy, Low Cost: The Nordic Thingy:52 Sensor Suite 1. Wireless technologies 2. EPICS controls of wireless sensors 3. ioc components 4. Integrated into CSS, and clients B. Improvements to Area Detector deployment and features at NSLS2 1. ADPluginBar/Dmtx – QR Code and data matrix code readers for EPICS Area Detector 2. ADLambda – Adding new features to an existing driver, and updating to build on newer OS 3. ADCompVision – Bringing Computer Vision to Area Detector 4. ADUVC – An area detector driver for USB Video Class devices 5. ADEmergentVision – An area detector driver for Emergent Vision Technologies 10 GigE and 25 GigE cameras

  2. NSLS-II Colloquium

    "NASA's Mars 2020 Mission – First Steps Towards Mars Sample Return"

    Presented by Kenneth Farley, Caltech

    Thursday, April 11, 2019, 4 pm
    Large Seminar Room, Bldg. 510

    Hosted by: John Hill

    Scientists have advocated for the return of samples from Mars for decades. The quest has finally begun in earnest: the Jet Propulsion Laboratory is in the final stages of construction of the Mars 2020 mission. Mars 2020 builds on the highly successful design of the Mars Science Laboratory (Curiosity Rover) and is updated with new landing capabilities, scientific instruments, and a very sophisticated rock sample collection system. Mars 2020's chief goals are to unravel the geology of its landing site, seek evidence of potential Martian biosignatures, and prepare a cache of several dozen samples for possible return to Earth by a future element of a notional Mars Sample Return campaign. NASA recently selected the mission's destination: Jezero Crater. This crater once held a very deep lake comparable in size to Lake Tahoe. Key geologic targets at the site include ancient Martian bedrock, lake sediments and especially a remarkably preserved river delta, and unusual carbonate-bearing rocks possibly precipitated from lake-water. Mars 2020 will launch in the summer of 2020, land on February 18, 2021, and rove the surface for at least two years. I am Project Scientist for Mars 2020 and will describe the goals and development of this mission, and of Mars sample return.

  3. NSLS-II Friday Lunchtime Seminar

    "Towards studying dynamics over 18 decades with correlation spectroscopy – first XPCS results from European XFEL"

    Presented by Felix Lehmkuehler, Coherent X-ray Scattering Group, DESY, Germany

    Friday, April 5, 2019, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    Many phenomena in soft matter physics and biology happen on microsecond timescales, e.g., folding kinetics of proteins, where the time scale is basically defined by the protein size. Despite of the importance of such processes, μs time scales are very difficult to access in X-ray scattering experiments at storage rings as well as in quasi-elastic neutron scattering. The time structure of the European XFEL with MHz pulse repetition rate in a bunch train enables for the first time structural studies of dynamics and kinetics at such time scales. A method to investigate such phenomena is X-ray photon correlation spectroscopy (XPCS), tracking changes of the coherent diffraction pattern, the so-called speckle pattern, over time. XPCS has become a well-established technique at modern storage ring sources studying timescales ranging from several 1000 s down to milliseconds. At FEL sources, the higher average flux and superior degree of coherence allow the access to shorter timescales down to femtoseconds using split-pulse techniques. On the other hand, sequential-pulse XPCS is limited by the repetition rate of the FEL pulses, i.e. about 8 to 50 ms at normal-conducting hard X-ray FEL sources such as LCLS (USA) and SACLA (Japan). The high repetition rate of the European XFEL enables dynamics measurement on sub-μs time scales, which is otherwise difficult to achieve at storage ring, neutron, pump-probe or lab-based experiments. In this talk, first dynamics measurements at FEL sources using correlation techniques will be introduced and recent results on prototypical soft matter samples as well as fs dynamics of liquid water will be discussed. Afterwards, results from our recent XPCS experiment at European XFEL will be discussed, where we successfully performed measurements of (sub-)µs dynamics of soft matter samples. Furthermore, special attention is paid on shot-to-shot and train-to-train fluctuations of coherence and beam pointing obtained by c

  4. NSLS-II Friday Lunchtime Seminar

    "X-ray holography correlation spectroscopy: How to probe stochastic dynamics on the nanoscale"

    Presented by Christopher Klose, Max Born Institute, Berlin, Germany

    Friday, March 29, 2019, 12:30 pm
    NSLS-II Bldg 744 Rm 156

    Hosted by: Ignace Jarrige

    Nanometer-scale spin configurations such as magnetic domains walls (DW) or skyrmions are attractive as information entities for spintronic applications as they can be generated and manipulated by electrical spin-polarized currents. Naturally, the function of such devices is crucially determined by the thermal stability of the magnetic configuration used for encoding the information. In our study, we have investigated thermally activated magnetic DW dynamics on timescales ranging from sub-seconds to hours under equilibrium conditions in a thin-film magnetic multilayer material based on 15 repetitions of Pt/CoFeB/MgO trilayers. Such multilayers were already successfully used to demonstrate the basic operation of a skyrmion-based racetrack memory [1]. For our investigations, we developed a new experimental approach combining real-space imaging via Fourier-transform holography [2] and x-ray photon correlation spectroscopy [3]. Both methods rely on detecting coherent far-field diffraction from a disordered sample —a pattern of magnetic up and down domains in our case. Magnetic contrast is achieved by tuning the wavelength of circularly polarized x-rays to the Co L3 absorption edge (1.6 nm). For slow timescales (> 3 min), the analysis is based on the difference of scattering patterns recorded with opposite x-ray helicity (Fig. 1a). On one hand, the Fourier inversion of this difference results in a real-space image of the domains in the field of view (FOV) defined by a circular optics mask on the sample (Fig. 1b). On the other hand, we use the difference as input for an adapted temporal correlation analysis. Already at slightly elevated temperatures (310 K), the resulting two-time correlation function of the magnetic configuration at times t1 and t2 (Fig. 1c) reveals time periods of high correlation, i.e., high stability interrupted by sudden extensive domain rearrangements as witnessed by the related images.

  5. NSLS-II Friday Lunchtime Seminar

    "Can We Make X-ray CT More Universal?"

    Presented by Jun Lim, Pohang Light Source-II, Korea, Republic of (South)

    Friday, March 29, 2019, 12 pm
    NSLS-II Bldg 744 Rm 156

    Hosted by: Ignace Jarrige

    Full-field transmission x-ray microscope (TXM) based on Fresnel zone plate is a promising and intuitive manner to take high quality phase contrast images with spatial resolution of tens of nanometers, applicable to both synchrotron radiation and laboratory source. In particular, computed tomography (CT) using hard x-rays of high penetration depth provides a high-resolution 3D image. However, the small field of view (FOV) of ~10 microns provides only a very limited volume (~10-5 mm3) of information. It primarily limits the application area of TXM. In this talk, I present a new type of TXM for CT that enlarge the FOV as large as diameter of the objective zone plate. With this method, sub-millimeter FOV can be realized while maintaining the nano-scale spatial resolution. Through experiment, we obtain more than 1000 times more volume (~10-2 mm3) of information than a typical TXM, at ~200 nm resolution. Its general applicability is demonstrated with integrated chips and Artemia cysts. We believe that this type of TXM can be particularly useful for industrial sample analysis where bulk properties are important.

  6. NSLS-II Friday Lunchtime Seminar

    "Selective Catalytic Olefin Epoxidation with MnII-exchanged MOF-5"

    Presented by Amanda Stubbs, MIT, Functional Inorganic & Organic Materials

    Friday, March 22, 2019, 9:30 am
    NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    Partial substitution of ZnII by MnII in Zn4O-(terephthalate)3 (MOF-5) leads to a distorted all-oxygen ligand field supporting a single MnII site, whose structure was confirmed by Mn K-edge X-ray absorption spectroscopy. The MnII ion at the MOF-5 node engages in redox chemistry with a variety of oxidants. With tBuSO2PhIO, it produces a putative MnIV-oxo intermediate, which upon further reaction with adventitious hydrogen is trapped as a MnIII−OH species. Most intriguingly, the intermediacy of the high-spin MnIV−oxo species is likely responsible for catalytic activity of the MnII-MOF-5 precatalyst, which in the presence of tBuSO2PhIO catalyzes oxygen atom transfer reactivity to form epoxides from cyclic alkenes with >99% selectivity. These results demonstrate that MOF secondary building units serve as competent platforms for accessing terminal high-valent metal−oxo species that consequently engage in catalytic oxygen atom transfer chemistry owing to the relatively weak ligand fields provided by the SBU.

  7. NSLS-II Friday Lunchtime Seminar

    "Results to date on the elimination of Insertion Device Motion control problems by the NSLS-II Insertion device working group"

    Presented by John Escallier, NSLS-II

    Friday, March 15, 2019, 12 pm
    NSLS-II Bldg. 744 Room 156

    Hosted by: Ignace Jarrige

    Control of Insertion Device gap motion by the use of the Delta Tau control platform requires a good understanding of several disciplines simultaneously. Physics, magnetics, mechanics, electronics, software, and control theory are all specialties needed to establish full control of the gaps. The ID working group is comprised of individuals who specialize in one or more of these disciplines, and have been quite successful at attacking and solving multiple issues related to the IVU devices. Improvements in accuracy and control have exceeded close to two orders of magnitude, while simultaneously keeping focus towards the eventual use of step and fly scanning of the gap in synchronous motion with other devices. As work on the first vendor's devices begins to ramp to completion, the group effort is being directed towards work on EPU's. This seminar will detail several of the problems encountered, how they were solved, and where the future lies.

  8. NSLS-II Colloquium

    "Challenges of Future Very Short Wavelength X-ray Free-Electron Lasers"

    Presented by Bruce Eric Carlsten, Los Alamos National Laboratory

    Thursday, March 14, 2019, 4 pm
    Large Seminar Room, Bldg. 510

    Hosted by: John Hill

    Future X-ray Free-Electron Lasers (XFELs) will produce coherent X-rays with energies greater than 20 keV, which will require electron beams with lower laboratory emittances and relative energy spreads than those in current XFELs such as LCLS or the European XFEL. To satisfy this requirement, electron beam energies will need to be higher than in current XFEL designs if conventional accelerator architectures are used, leading to increased construction and operation costs. To provide design margin for these future XFELs at the lowest possible electron beam energies, novel schemes may be employed to suppress or eliminate the present limitations in XFEL performance. This talk will describe the dominant electron-beam instabilities and other effects (coherent synchrotron radiation, undulator resistive wall wakes, microbunch instability, and intrabeam scattering) and will describe a novel accelerator architecture to suppress the worst effects from them. Design trades to improve performance at lower beam energies will also be described. The baseline parameters for the proposed XFEL at Los Alamos (the MaRIE XFEL, designed to have an X-ray energy of 42 keV) will be used to illustrate these effects.

  9. NSLS-II Friday Lunchtime Seminar

    "Dynamic Investigations of functional proteins using synchrotron radiation and gold nano-crystals at SPring-8"

    Presented by Hiroshi Sekiguchi, SPring8, Japan

    Friday, March 8, 2019, 12:30 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    In addition to the static crystallographic information regarding a 3D structure of proteins, dynamic information regarding a protein's conformational changes would be helpful in elucidating the molecular mechanisms that regulate protein functions, such as ion channel gating and ligand-induced receptor activation. Such local and dynamic information can be obtained using optical microscopy with recently developed single molecule techniques, and we think that the technique with synchrotron X-rays would be more powerful technique because of its brilliance, its short wavelength of light, and its transparency. Small-angle X-ray scattering (SAXS) is one of well-established technique to investigate the nanoscale structure of protein under physiological conditions and structural changes in response to various external conditions and we have probed a compact intermediate state of calmodulin in the process of target binding [1,2] etc. And we have proposed a single molecule technique that utilizes synchrotron X-rays to monitor the internal motions of a single protein. We call it diffracted X-ray tracking (DXT) and it can detect atomic-scale dynamic motion of the protein at the single molecular level with several tens of microseconds time resolution [3]. In DXT, a target protein is labeled with a nanocrystal with a size of several tens of nanometers and the motions of the nanocrystal coupled with the protein's motions are recorded as the trajectories of diffraction spots from the nanocrystal [4-6]. At the seminar, we will present recent progress of such investigation for biomolecules at SPring-8 [7].

  10. NSLS-II Friday Lunchtime Seminar

    "A "coherent" picture of (some) Quantum Materials"

    Presented by Claudio Mazzoli, BNL / NSLS-II

    Friday, March 8, 2019, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    Quantum Materials are attracting an increasing level of attention in order to understand and fully exploit their peculiar properties for innovative potential applications. The investigation of their relevant electronic phases, their dynamics and their coherence length scales is key to produce a consistent microscopic picture of their functionalities and response to external stimuli. In my talk, I will present some recent investigation on quantum materials performed at CSX (23-ID-1), focusing on their electronic order parameters and interactions, inhomogeneity and time evolution. Examples will include charge ordering in cuprate HTSC, magnetic ordering in artificial patterned samples and nickelates, exotic magnetic phases in multilayers.

  11. NSLS-II Friday Lunchtime Seminar

    "Non-magnetic gap in the topological insulators"

    Presented by Turgut Yilmaz, NSLS-II

    Friday, March 1, 2019, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    In this talk, I will introduce the electronic structure of Cr-doped Bi2Se3 / pristine Bi2Se3 heterostructure grown by molecular beam epitaxial method. We realized that such heterostructure provides sharper electronic states in angle resolved photoemission experiments. This promotes a new strategy to study the impact of impurities on the surface states of topological insulators. Furthermore, I will show that the apparent gap at the Dirac point of topological insulators in the non-magnetic state is indeed formed by the resonant states. We confirm this by performing the first principle band structure calculation and angle resolved photoemission spectroscopy with on and off-resonant photon energies.

  12. NSLS-II Friday Lunchtime Seminar

    "Formation and dynamics of organo-mineral associations in redoximorphic soils"

    Presented by Selina Tenzer, University of Hohenheim, Germany

    Friday, February 22, 2019, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    Dissolved soil organic matter (SOM) hinders the crystal growth of Fe and Mn oxides but promotes the formation of metal-OM complexes. The strength of the interactions between SOM and the Fe(O,OH)6-octahedra depends, besides pH and ionic strength, on the available functional groups. We investigate the formation of oxides under alternating redox conditions in the presence of two isotopically labelled organic model substances: vanillin (lignin component with a reactive phenol group) and alanine (amino acid with a carboxyl and an amino group). Combining XRF, µXANES and µXRD at 5-ID will allow to identify Fe and Mn oxides, describe their crystallinity and estimate the importance of organic forms of Fe and Mn. Later, we will study the spatial distribution of vanillin and alanine across mineral surfaces by NanoSIMS.

  13. NSLS-II Friday Lunchtime Seminar

    "Magneto-electric waves in f-electron magnets"

    Presented by Nicolas Gauthier, Stanford University & SLAC

    Friday, February 15, 2019, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    The intertwining of electric, magnetic and structural degrees of freedom in materials is at the heart of novel strongly correlated phases such as magnetoelectric multiferoicity, superconductivity and heavy fermion ground states. Isolating the contributions of di erent degrees of freedom and characterizing their interplay are fundamental aspects to understand such unconventional phases. The multipolar expansion of the electronic con guration provides a powerful framework to attain this objective. As an example, I will present how we can reveal the role of electric quadrupole moments by measuring magnetic dipolar waves with neutron scattering in the frustrated magnet SrDy2O4. Our results indicate that electric e ects of the 4f-electrons can dominate over the magnetism in insulators and this encourages a reassessment of the description of rare-earth based magnets with unconventional properties.

  14. NSLS-II Collquium

    "Resonant x-ray scattering from soft materials as a probe of molecular orientation fluctuations at the nanoscale"

    Presented by Noel A. Clark, University of Colorado, Boulder

    Thursday, February 14, 2019, 4 pm
    Large Seminar Room, Bldg. 510

    Hosted by: John Hill

    Orientation fluctuations are ubiquitous features of soft materials on length scales ranging from nanometers in the rotational dynamics of single molecules, to the macroscopic deformation of local orientational order in liquid crystals, polymers, and biomaterials. Here we present the application of depolarized resonant soft x-ray scattering (DRSoXS) as a selective probe of molecular orientation fluctuations at the nanoscale. This technique is demonstrated by determination of the wavevector spectrum of thermally generated collective reorientations in a nematic liquid crystal using Carbon K??-edge resonant scattering (incident wavelength = 4.4nm). DRSOXS uniquely reveals transient, short-range heliconical molecular assemblies and their pretransitional development, as ordering into a chiral three-dimensional helical state is approached.

  15. NSLS-II Friday Lunchtime Seminar

    "Rechargeable Sodium-Ion Batteries"

    Presented by Kyung-Wan Nam, Dongguk University, Seoul, Korea, Republic of (South)

    Friday, February 8, 2019, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    Rechargeable sodium-ion batteries (SIBs) are now attracting special attention with a great cost advantage over rechargeable lithium-ion batteries (LIBs) especially in the field of large-scale applications. For the successful development of the SIBs, it is imperative to find new cathode and anode materials with high capacity, high power, and long cycle life. With this perspective, we have examined the electrochemical properties of O3-layer structured oxides, Na3M(II)2M(V)O6, with a honeycomb ordering of M(II) and M(V) in the metal layer for the cathode material in SIBs.[1] One of this class materials, Na3Ni2BiO6, can reversibly deliver specific discharge capacities of up to 109 mAh/g with very flat voltage plateaus ~3.5V vs. Na/Na+. Structural changes occurring during charging/discharging investigated by using in situ X-ray diffraction (XRD) are correlated with its long cycle life. Long and short-range structure changes at various state of (dis)charge have been also probed ex-situ using combined synchrotron-based high-resolution X-ray powder diffraction (HRPD) and extended X-ray absorption fine structure (EXAFS). Some of its derivatives with increased redox voltages will also be presented. For the anode materials, various compositions of transition metal oxides including Ti and Fe elements having tunnel based structures (single- and double- tunnels) are explored as rechargeable SIBs.[2] Detailed electrochemical results combined with structural characterization will be presented in the seminar. References: [1] D.S. Bhange, G. Ali, D.-H. Kim, D.A. Anang, T.J. Shin, M.G. Kim, Y.-M. Kang, K.Y. Chung, K.-W. Nam, J. Mat. Chem. A 5 (2017) 1300-1310. [2] D.S. Bhange, G. Ali, J.-Y. Kim, K. Y. Chung, K.-W. Nam, J. Power Sources 366 (2017) 115-122.

  16. NSLS-II Friday Lunchtime Seminar

    "Phase Transition Kinetics of Close-Packed Block Copolymer Micelles"

    Presented by Sangwoo Lee, Rensselaer Polytechnic Institute, Troy, NY

    Friday, February 1, 2019, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: Ignace Jarrige

    In the past decades, the structures of spherical particle packing have been intensively investigated to understand the origin of materials structures and associated properties. However, despite its equal importance, the phase transformation kinetics of spherical particles has been relatively poorly understood. We investigated close-packed structures of spherical block copolymer micelles induced by rapid cooling of disordered micelles using small angle X-ray scattering experiments conducted at the 11-CMS and 12-SMI lines. We found that depending on the depth of quenching, disordered block copolymer micelles self-assemble into three different close-packed structures: face-centered cubic (fcc), random stacking of hexagonal-close packed layers (rhcp), and hexagonal-close-packed (hcp) structures as the depth of temperature quenching increases. Cooling and heating of these close-packed micelle solutions reveal that the hcp and rhcp structures are long-lasting metastable structures that eventually transform to stable fcc. Close-inspection of the 2D small angle X-ray scattering patterns shows that the formation of these metastable structures is correlated with the size of crystallites. The Laplace pressure is attributed to the origin of the formation of the metastable structures.

  17. NSLS-II Friday Luncheon Seminar

    "EDRIXS: An open source toolkit for simulating spectra of resonant inelastic x-ray scattering"

    Presented by Yilin Wang, Condensed Matter Physics & Material

    Friday, January 25, 2019, 12 pm
    NSLS-II, Bldg. 743 Rm 156

    Hosted by: Ignace Jarrige

    In this talk, we present an open source toolkit (dubbed EDRIXS) to facilitate the simulations of RIXS spectra of strongly correlated materials based on exact diagonalization (ED) of certain model Hamiltonians. The model Hamiltonian can be from a single atom, small cluster or Anderson impurity model, with model parameters from density functional theory plus Wannier90 or dynamical mean-field theory calculations. The spectra of x-ray absorption spectroscopy (XAS) and RIXS are then calculated using Krylov subspace techniques. This toolkit contains highly efficient ED, XAS and RIXS solvers written in modern Fortran 90 language and a convenient Python library used to prepare inputs and set up calculations. We first give a short introduction to RIXS spectroscopy, and then we discuss the implementation details of this toolkit. Finally, we show several examples to demonstrate its usage.

  18. NSLS-II Friday Lunchtime Seminar Series

    "Computer Vision and new areaDetector features"

    Presented by Kazimierz Gofron, NSLS-II

    Friday, January 18, 2019, 12 pm
    NSLS-II Bldg. 743 Rm 156

    Hosted by: Ignace Jarrige

  19. NSLS-II Colloquium Series

    "Superconductivity: Where we are and where we are going"

    Presented by Prof. Robert Cava, Princeton University, NJ

    Thursday, December 13, 2018, 4 pm
    Hamilton Seminar Room, Bldg. 555

    Hosted by: John Hill

    The discovery of superconductivity, the transmission of electrical current with zero energy loss, recently passed its 100th anniversary. This truly remarkable property of matter, found at cryogenic temperatures, has made its way into a variety of important uses in modern society, but nature has not yet given us the ultimate practical material that will change the world through its lossless transmission of electrical energy over long distances. Research on this complex problem in materials science persists in the world at many levels, and progress is continuously made on both scientific and practical fronts, in spite of the impatience that is often displayed by both the scientific and lay public. In this talk I will briefly describe where we are in this field, and how we got here, and describe the vision that some have had for where we should be going. Because my personal research is in the discovery of new superconducting materials, only one facet among the larger set of fundamental and practical issues currently under study, the talk will be given from that perspective.

  20. NSLS-II Friday Lunchtime Seminar

    "Magnetic skyrmions at room temperature - statics, dynamics, and high resolution imaging"

    Presented by Dr. Felix Buttner, Dept of Mat Sci & Eng , MIT

    Friday, December 7, 2018, 12 pm
    NSLS-II Bldg 743 Room 156

    Hosted by: Ignace Jarrige

    Magnetic skyrmions are the smallest non-trivial entities in magnetism with great potential for data storage applications. These chiral and topological quasi-particles furthermore exhibit fascinating static and dynamical properties that render them the ideal candidates to study new physics in high spin-orbit coupling materials. In this talk, I will first give a general introduction to the field of skyrmionics and the fundamental properties of skyrmions that derive from their energetics. I will then discuss various ways of creating and stabilizing room-temperature skyrmions experimentally, as well as how we can move them and observe their topological dynamics via high resolution time-resolved x-ray imaging. I will conclude with perspectives of future research in this field and related areas.

  21. NSLS-II Friday Lunchtime Seminar

    "A Novel Stripe Phase in Bi-2212 Cuprate"

    Presented by Yang Ding, Center for High Pressure Science & Technology Advanced Research, China

    Friday, November 30, 2018, 12 pm
    NSLS-II Bldg 743 Room 156

    Hosted by: Ignace Jarrige

    High-temperature superconductivity (HTSC) is one of the most important discoveries at contemporary condensed matter physics. However, its mechanism is still unclear. One way to approach this problem is to search for the controlling parameters of HTSC transition temperature Tc. In this presentation, we will introduce a novel type stripe phase in Bi2212 that is revealed by nano-imaging technique. Intriguingly, the evolution of the stripe phase is in coincidence with the change of Tc, which implies a correlation between the Tc and the optimal inhomogeneity in the cuprate.

  22. NSLS-II Seminar

    "Structure/Properties of Thin Film Composite Membranes for Water Purification"

    Presented by Christopher M. Stafford, NIST, Gaithersburg, MD

    Tuesday, November 20, 2018, 11 am
    NSLS-II Bldg. 744

    Hosted by: Ben Ocko

    Access to sustainable sources of clean water is critical to manufacturing, agriculture, energy production, public health, and national security. One prominent technology for meeting this need is membrane-based separations of water and dissolved contaminants/solutes via nanofiltration and reverse osmosis. This field is dominated by polymer-based membranes and has relied on complex, empirically optimized chemistries and structures based on material selections made decades ago. The resulting processes are energy intensive and suffer from limited performance lifetimes. We are bringing our deep expertise in measurement science and polymer science to address this critical technology, specifically by establishing fundamental structure/property relationships that correlate membrane topology and dynamics to membrane performance. In this talk, I will describe our recent efforts in synthesizing model membrane materials based on molecular layer-by-layer deposition of aromatic polyamide networks, as well as our measurements of swelling, crosslink density and mechanics of both model and commercial membrane materials. This understanding will enable industry to develop and manufacture next generation, energy-efficient membrane materials.

  23. NSLS-II Friday Lunchtime Seminar

    "Delivering Focused, Rapidly Tunable, Stable Monochromatic X-Rays to the GSECARS APS 13-ID-E Microprobe Endstation"

    Presented by Peter J. Eng, CARS and JFI, University of Chicago

    Friday, November 9, 2018, 12 pm
    NSLS-II Bldg. 743 Rm 156

    Hosted by: Ignace Jarrige

    With the APS-U scheduled for 2023 GSECARS, is designing and testing enhancements to beamline instrumentation to optimize the benefits of this upgraded source. The sector 13-ID-E microprobe endstation studies a wide range of environmental, earth and planetary problems, requiring a rich array of techniques and instrumentation. Central to the success of this program is the insertion device and the x-ray optics that produce, monochromate and focus the beam on the sample. All aspects of this system are under review. Design efforts are focused on 1) managing the increased total power and power density of the APS-U undulator source; 2) improved beam and sample stability; 3) improved focusing optics; and 4) rapid and high duty cycle scanning of the incident beam energy. This is an ongoing development effort with a number of enhancements schedule to be installed in the 1st quarter of 2019. Other components are in the design or prototype phase, drawing on collaboration between universities, national labs and industry.

  24. NSLS-II Friday Lunchtime Seminar

    "Materials Tribology: An Application-Driven Field with Rich Opportunities for Fundamental Studies of Surface Chemistry, Physics, Structure"

    Presented by Brandon A. Krick, Department of Mechanical Engineering and Mechanics, Lehigh University

    Friday, November 2, 2018, 12 pm
    NSLS-II Bldg. 743 Rm 156

    Hosted by: Ignace Jarrige

    The significant economic (~3-6% of developed countries GDP) and environmental (several percent of our annual energy consumption) impacts of friction and wear make tribology is an important, application-driven field. However, there is an opportunity and need for inherently fundamental studies on surface chemistry, physics and structure to elucidate fundamental mechanisms for friction and wear. The non-equilibrium and transient nature of shear-induced changes caused by contacting surfaces in relative motion requires both in situ and ex situ advanced characterization techniques; many of these only available at the light source at Brookhaven. A brief overview of shear-induced (sliding friction/wear) alterations of surfaces will be presented for material systems including: - environmental and tribochemistry molybdenum disulphide based coatings for space applications - shear-induced band bending in GaN - mechanochemistry of polymer nanocomposites

  25. NSLS-II Friday Lunchtime Seminar

    "Thai heritage glasses studied by synchrotron radiation"

    Presented by Dr. Wantana Klysubun, Synchrotron Light Research Institute, Thailand

    Friday, October 26, 2018, 12 pm
    NSLS-II Bldg. 744 Rm 156

    Hosted by: Ignace Jarrige

  26. NSLS-II Friday Lunchtime Seminar

    "RIXS study of the charge and magnetic evolution in La2-xCexCuO4 combi-film"

    Presented by Xuerong Liu, Shanghai Tech University, China

    Friday, October 19, 2018, 12 pm
    NSLS-II Bldg. 743 Rm 156

    Hosted by: Ignace Jarrige

    Different from the simple one-band Hubbard model prediction, it has been recognized that the cuprate superconductors are electron-hole asymmetric. Recent RIXS work on the electron-doped Nd2-xCexCuO4 by K. Ishii et al. [1] and W. S. Lee et al. [2] reported a hardening of the spin excitations and the emergence of a charge excitation mode. Both these observations are in distinct contrast to that reported on the hole doped side, and brought attention again to the profound electron-hole asymmetry issue in the cuprates. Taking the advantage of a La2-xCexCuO4 combi-film, namely a film with large range doping gradient distribution, we studied the evolution of the charge and magnetic excitations from optimal- to over-doping systematically in fine steps. Our results establish the universality of the previous observation for the electron-doped cuprates. And more importantly, the doping dependent evolutions show that the magnetic and charge excitations are not the two faces of a coin. Rather, the spin-correlation roots in the short range correlation, and the charge-fluctuation stems from long range Coulomb interaction. [1] K. Ishii et al, Nat. Commun. 5, 3714 (2014). [2] W. S. Lee et al, Nat. Phys. 10, 883 (2014).

  27. NSLS-II Friday Seminar Series

    "Chasing Protons in Lithium Batteries"

    Presented by Zonghai Chen, Argonne National Laboratory

    Friday, October 12, 2018, 12 pm
    NSLS-II Bldg. 743 Rm 156

    Hosted by: Ignace Jarrige

    Nickel-rich lithium transition metal oxides have been recently considered as one of most promising cathode materials for high energy density lithium-ion batteries. However, the instability of the cathode electrolyte interface has been the major technological barrier for the development of nickel-rich cathodes. The early research has simply assigned this interfacial instability to the electrochemical oxidation of the commonly used carbonate solvents without much discussion on the nature of the parasitic reactions. A proprietary high precision electrochemical system was built in-house to quantitatively measure the rate and kinetics of the side reactions between the delithiated cathode and the non-aqueous electrolyte. Our results clearly indicated the dominant chemical reaction within the working potential window is the chemical, not electrochemical, reaction between the intermediate phase of cathode and the electrolyte, generating locally concentrated protons at the surface of the cathode materials. Figure 1 shows a generic mechanism of parasitic reactions occurring at the interface of cathode materials. Additional help from advanced characterization tools, such as synchrotron probes, will be also be discussed.

  28. NSLS-II Colloquium Series

    "Biophysical Studies of an RNA Virus particle and its Maturation: Insights into an Elegantly Programmed Nano-machine"

    Presented by John E. (Jack) Johnson, Department of Integrative Structural and Computational Biology, The Scripps Research Institute

    Thursday, October 11, 2018, 4 pm
    Large Seminar Room, Bldg. 510

    Hosted by: John Hill

    Nudaurelia Capensis ? Virus (N?V) is a eukaryotic, quasi-equivalent, RNA virus, with a T=4 surface lattice, where maturation is dramatic (a change in particle size of 100Å) and is novel in that it can be investigated in vitro. Here we use X-ray crystallography, biochemistry, Small Angle X-ray Scattering, and electron cryo-microscopy and image reconstruction (CryoEM), to characterize maturation intermediates, an associated auto-catalytic cleavage, the kinetics of morphological change and to demonstrate that regions of N?V subunit folding are maturation-dependent and occur at rates determined by their quasi-equivalent position in the capsid. Matsui, T., Lander, G. C., Khayat, R., and Johnson, J. E. 2010. Subunits fold at position-dependent rates during maturation of a eukaryotic RNA virus. Proc Natl Acad Sci U S A 107:14111-5. Veesler, D., and Johnson, J.E. 2012. Virus Maturation. Annual review of biophysics 41:473-496. Doerschuk, P. C., Gong, Y., Xu, N., Domitrovic, T., and Johnson, J. E. 2016. Virus particle dynamics derived from CryoEM studies. Curr Opin Virol 18:57-63.

  29. NSLS-II Friday Seminar

    "Highly Active and Stable Carbon Nanosheets Supported Iron Oxide for Fischer-Tropsch to Olefins Synthesis"

    Presented by Congjun Wang, National Energy Technology Laboratory, Pittsburgh, PA

    Friday, October 5, 2018, 12 pm
    NSLS-II Bldg. 743 Rm 156

    Hosted by: Ignace Jarrige

    Light olefins production utilizes the energy intensive process of steam cracking. Fischer-Tropsch to olefins (FTO) synthesis potentially offers a more sustainable alternative. Here we show a promising FTO catalyst comprised of iron oxide nanoparticles supported on carbon nanosheets (CNS) fabricated from the carbonization of potassium citrate, which incorporates well dispersed K-promoter throughout the CNS support. This catalyst exhibits, to the best of our knowledge, the highest iron time yield of 1790–1990 μmolCO/gFe•s reported in the literature, 41% light olefins selectivity, and over 100 hours stable activity, making it one of the best performing FTO catalysts. Detailed characterization, including synchrotron X-ray spectroscopy, illustrates that the CNS support facilitates iron oxide reduction to metallic iron, leading to efficient transformation to the active iron carbide phase during FTO reaction. Since K is a commonly used promoter, our K-promoted CNS support potentially has broad utility beyond the FTO reactions demonstrated in the current study.

  30. NSLS-II Friday Lunchtime Seminar

    "Shape-Symmetry Incommensurate Polymer Crystals Directed by Liquid-liquid Interface"

    Presented by Prof. Christopher Li, Department of Materials Science and Engineering, Drexel University

    Friday, September 28, 2018, 12 pm
    NSLS-II Bldg. 743 Rm 156

    Hosted by: Ignace Jarrige

    Crystallization is ubiquitous in nature and semicrystalline polymers are of crucial importance in our daily life. Compared with small molecules, polymers crystallize via a more complex pathway because of their long chain nature and various metastable states associated with polymer crystals. In this talk, I will show that this complex conformational change of polymer chains upon crystallization can be employed to design and fabricate functional nanomaterials. We will focus on crystallization directed by liquid/liquid interface. Not only can this type of dynamic interface direct the crystallization pathway, it can also alter chain packing in the final crystals, leading to intriguing macroscopic properties. In particular, curved interface, which is incommensurate with the classical translation symmetry, frustrates chain packing, and induced defect formation, a topic that will be discussed in the context of recently reported spherical crystallography.

  31. NSLS-II Friday Luncheon Seminar

    "X-ray sparse-angle Bragg ptychography"

    Presented by Dr. Peng Li, Institut Fresnel (CNRS), Marseille, France

    Friday, September 21, 2018, 12:30 pm
    NSLS-II Bldg. 743 Rm 156

    Hosted by: Ignace Jarrige

    X-ray Bragg ptychography is a scanning coherent diffraction imaging microscopy technique that can produce 3D maps of the crystalline structure of an extended nanostructured crystal at about 10nm resolution. With sparse-angle Bragg ptychography, the 3D maps can be extracted from an extremely undersampled data-set. This new strategy substantially reduces the acquisition time and mitigates problems, linked to radiation damage and instabilities, faced by conventional Bragg ptychography. However, the success of the image reconstruction is based on a good knowledge of the probe, whose uncertainties degrade the object reconstruction. In this talk, we solve this problem by proposing a simultaneous reconstruction of the probe and object functions. This is based on a strong but natural constraint of the probe properties. We demonstrate our approach on a He-implanted poly-crystalline Tungsten sample measured at ID01-ESRF. These findings open new possibilities for this imaging technique.

  32. NSLS-II Seminar

    "X-ray spectroscopy of transition metal oxides"

    Presented by Frank de Groot, Utrecht University, Netherlands

    Thursday, August 23, 2018, 11 am
    NSLS-II Building 744 Room 156

    Hosted by: Lisa Miller

    Some new developments in x-ray absorption (XAS) and resonant inelastic x-ray scattering (RIXS) will be discussed. An introduction is given of XAS, including the oxygen K edge, metal K edge and metal L edge [1,2]. The main part of the talk deals with resonant inelastic x-ray scattering (RIXS) In 2p3d RIXS one scans through the 2p XAS edge and measures the low energy excitations, including phonons, magnons, dd-excitations and charge transfer. The 100 meV resolved 2p3d RIXS spectra of ruby (Cr3+ in Al2O3), Fe3O4 and LaCoO3 will be discussed [3,4]. The present experimental resolution of 30 to 100 meV allows the detailed observation of the electronic structure, including the determination of crystal field parameters, covalency parameters and spin-orbit coupling, but also the momentum dependence of magnons and other low energy excitations. Related to the RIXS measurements is the analysis of Fluorescence yield (FY) detected x-ray absorption spectra (XAS), including the intrinsic deviations of FY-XAS spectral shape from the XAS spectrum that is important for measurements with x-ray free electron lasers [5,6]. [1] Core Level Spectroscopy of Solids Frank de Groot and Akio Kotani (Taylor & Francis CRC press, 2008) [2] Download the x-ray spectroscopy simulation software at http://www.anorg.chem.uu.nl/CTM4XAS/ [3] Huang et al. Nature Comm. 8, 15929 (2017). [4] Tomiyasu et al. Phys. Rev. Lett. 119, 196402 (2017) [5] F.M.F. de Groot, Nature Chemistry 4, 766 (2012) [6] Mitzner et al. J. Phys. Chem. Lett. 4, 3641 (2013)

  33. NSLS-II Colloquium Series

    "Mulling over Nanoemulsions: Interfacial Molecular Structure, Stabilization and Assembly"

    Presented by Prof. Geraldine (Geri) Richmond, University of Oregon

    Thursday, August 9, 2018, 4 pm
    Large Seminar Room, Bldg. 510

    Hosted by: John Hill

    Nanoemlusions are finding numerous applications in the fields of pharmaceuticals, food production, materials synthesis and cosmetics. With the search for broader and improved usage of these unique droplets comes the need to better understand the molecular interactions at the surface that lead to their stabilization. This presentation will focus on our most recent efforts in measuring the molecular structure of the oil-water interface and the unique environment it provides for adsorption of molecules, surfactants and macromolecules at both planar and nanoemulsion oil/water interfaces. The studies are a combination of spectroscopic and thermodynamic measurements coupled with theoretical simulations.

  34. NSLS-II Friday Luncheon Seminar

    "Homoepitaxial growth of SrTiO3 by Pulsed Laser Deposition: energetic vs thermal growth"

    Presented by Jeff Ulbrandt, University of Vermont

    Friday, August 3, 2018, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: M. Abeykoon, S. Chodankar, B. Ocko, T. Tanabe, J. Thieme

  35. Summer Sundays

    "Brilliant Light, Dazzling Discoveries - National Synchrotron Light Source II"

    Sunday, July 29, 2018, 10 am
    Berkner Hall, Room B

  36. NSLS-II Friday Lunchtime Seminar

    "Manipulating sound propagation beyond the hypersonic range: recent IXS results"

    Presented by Alessandro Cunsolo, NSLS-II / BNL

    Friday, July 13, 2018, 12 pm
    NSLS-II

    Hosted by: M. Abeykoon, S. Chodankar, B. Ocko, J. Thieme, G. Wang

  37. NSLS-II Friday Lunchtime Series

    "Investigating slow kinetic processes using synchrotron radiation: A case study of cement hydration in nuclear waste cements"

    Presented by Claire L. Corkhill, University of Sheffield, United Kingdom

    Friday, June 29, 2018, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: M. Abeykoon, S. Chodankar, B. Ocko, J. Thieme, G. Wang

  38. NSLS-II Friday Luncheon Series

    "The Helmholtz Imaging Platform (HIP): Imaging Sciences in Germany"

    Presented by Alexander Pichler, DESY Hamburg, Germany

    Friday, June 22, 2018, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: M. Abeykoon, S. Chodankar, B. Ocko, T. Tanabe, J. Thieme

  39. NSLS-II Seminar

    "Understanding microstructure evolution in lithium battery electrodes through coupled modeling and experiments"

    Presented by Ming Tang, Dept of Materials Science & NanoEngineering, Rice University, Houston, TZ

    Monday, May 7, 2018, 11 am
    NSLS-II Bldg. 744 Room 156

    Hosted by: Yong Chu & Jun Wang

    Like most materials, there exist very rich microstructure evolution phenomena in lithium battery electrode compounds during battery operation. Elucidating such phenomena through combined modeling and characterization including synchrotron-based techniques could yield valuable insights on how electrode structure should be designed and tailored at the mesoscale to enable stepwise improvement in battery performance. In this talk, I will first present our recent study on the unique aspects of phase transformation kinetics in Li-ion battery electrodes, using LiFePO4 as a model system. Through combined phase-field modeling and transmission x-ray microscopic observation of Li deintercalation process in LiFePO4 microrods, we discovered that intercalation-induced phase transformations can proceed in several distinct kinetic modes with varied electrochemical conditions and particle geometry. In particular, a hybrid mode, in which phase growth is surface-reaction-limited or bulk-diffusion-limited along different directions, is revealed for the first time. In the surface-reaction-limited transformation regime, we predict a surprising effect of antisite defects on accelerating phase boundary migration velocity by two orders of magnitude over defect-free LiFePO4 due to defect-induced increase in the surface reaction area. This finding suggests defect engineering as a fruitful approach to enhance the rate performance of intercalation compounds. The second part of this talk concerns the fundamental mechanism of dendrite growth on Li metal surface during electroplating, which presents a major challenge to the adoption of Li metal anodes in rechargeable batteries. Combining Li electroplating experiments and modeling, we obtained a key insight that Li dendrite growth is a stress-driven process, which is initiated by the compressive residual stress developed in deposited Li during battery cycling. Accordingly, elimination of the plating stress, e.g. via the use of soft substrate for Li

  40. Brookhaven Women In Science Speaker

    "The Exciting World of Molecules: An Image From Within Using Light Sources and Free Electron Lasers"

    Nora Berrah, University of Connecticut

    Thursday, April 26, 2018, 4 pm
    Large Seminar Room, Bldg. 510

    Professor Berrah, chair of the University of Connecticut Physics Department, will take us on a fascinating voyage through the molecular world. All that surrounds us is ultimately made of atoms and molecules; these materials are not static—they are dynamic and move. Berrah uses x-rays from light sources and free electron lasers (FELs) to study how they move, why they move, and what it means to us. During her talk, she will share her recent studies on fullerenes, a molecule that may be used for drug delivery systems to the body, in lubricants, and as catalysts. Nora is the recipient of numerous awards. She recently received the Davisson-Germer Prize from the American Physical Society. Nora is also an active member of COACh, an organization that is working to increase the number of women scientists and engineers, and the success of their careers, through innovative programs and strategies. Coffee and cookies will be available at 3:30 p.m.

Currently showing events from the past year. See all past events »

  1. MAY

    20

    Monday

    2019 NSLS-II & CFN Joint Users' Meeting

    May 20-22, 2019

  2. MAY

    29

    Wednesday

    LiX Solution Scattering Workbench

    May 29-31, 2019

  3. JUN

    17

    Monday

    4th International Conference on Resonant Elastic X-ray Scattering (REXS 2019)

    June 17-21, 2019

  4. JUN

    23

    Sunday

    11th International Conference on Inelastic X-ray Scattering (IXS2019)

    June 23-28, 2019

  5. JUL

    1

    Monday

    Teacher Training: Exploring Proteins with a New Light

    July 1-3, 2019

  1. In Celebration of International Women's Day 2019

    March 8, 2019

  2. LiX Solution Scattering Workbench

    February 14-16, 2019

  3. Short Course: Introduction to X-ray Absorption Spectroscopy

    November 6-8, 2018

  4. NOBUGS 2018: New Opportunities for Better User Group Software

    October 22-26, 2018

  5. NSLS-II Pair Distribution Function School 2018

    September 17-19, 2018

  6. 10th International Workshop on X-ray Radiation Damage to Biological Samples

    September 13-14, 2018

  7. Coherence 2018: International Workshop on Phase Retrieval and Coherent Scattering

    June 24-28, 2018

  8. 2018 NSLS-II and CFN Users' Meeting

    May 21-23, 2018

  9. Data Analysis and Modeling of XANES and EXAFS Spectra: Applications to Nanomaterials

    November 1-3, 2017

  10. Synchrotron Environmental Science Symposium 7: Illuminating the Links Between Environmental Science and Human Health

    October 30 - November 1, 2017

  11. 2017 NSLS-ll and CFN Users' Meeting

    May 15-17, 2017

  12. High-Brightness Synchrotron Light Source Workshop

    April 26-27, 2017

  13. X-ray Absorption Fine Structure Spectroscopy (XAFS) Short Course: Principles and Applications

    November 2-4, 2016

  14. 14th International Conference on Surface X-ray and Neutron Scattering (SXNS14)

    July 10-14, 2016

  15. 2016 NSLS-ll and CFN Users' Meeting

    May 23-25, 2016

  16. Short Course: Advanced Topics in XAFS Data Analysis and Modeling

    November 5-7, 2015

  17. 8th International Workshop on Infrared Microscopy and Spectroscopy using Accelerator Based Sources

    October 11-15, 2015

  18. Collaboration Meeting on "Simulation and Modeling for SR Sources and X-Ray Optics"

    October 1-2, 2015

  19. NSLS-II Strategic Planning Workshop

    September 24-25, 2015

  20. 23rd International Congress on X-ray Optics and Microanalysis (ICXOM23)

    September 14-18, 2015

  21. Complementary Methods in X-ray Spectroscopic, Structural, and Imaging Techniques

    July 13-14, 2015

  22. 12th International Conference on Synchrotron Radiation Instrumentation (SRI 2015)

    July 6-10, 2015

  23. BES Facilities Computing Working Group Meeting - May 21-22, 2015

    May 21-22, 2015

  24. 2015 NSLS-II & CFN Joint Users' Meeting

    May 18-20, 2015

  25. First Science at the ABBIX Beamlines

    April 21-22, 2015

  26. Short Course: Methods and Applications of X-Ray Absorption Fine Structure Spectroscopy

    November 13-15, 2014

  27. NSLS "Last Light"

    September 30, 2014

  28. Remote Access Data Collection: Automation and Robotics at the SSRL Protein Crystallography Beam Lines

    July 17-18, 2014

  29. Joint NSLS/NSLS-II & CFN Users' Meeting

    May 19-21, 2014

  30. X9 SAXS Workbench

    April 24-27, 2014

  31. Industrial Research at NSLS-II

    April 8-9, 2014

  32. X6A Workbench: Hands-on Synchrotron Structural Biology

    February 25-28, 2014

  33. X6A Workbench: Hands-on Synchrotron Structural Biology

    October 29 - November 1, 2013

  34. In-situ Methods of X-ray Absorption Spectroscopy

    October 24-26, 2013

  35. NSLS-II Early Experiment Workshop: IXS Focused Session

    October 1, 2013

  36. NSLS-II First-Experiments Workshop

    August 12-13, 2013

  37. X6A Workbench: Hands-on Synchrotron Structural Biology

    June 25-28, 2013

  38. NSLS and CFN Users' Meeting

    May 20-22, 2013

  39. Seventh International Workshop on Radiation Safety at Synchrotron Radiation Sources

    May 8-10, 2013

  40. RapiData 2013

    April 21-26, 2013

  41. X9 SAXS Workbench

    April 18-21, 2013

  42. MXLS13 "New Opportunities for Magnetic Dynamics and Materials at NSLS-II and MAX-IV”

    March 24-28, 2013

  43. X6A Celebrates Its 10th Anniversary!

    February 1, 2013

  44. X6A Workbench: Hands-on Synchrotron Structural Biology

    January 28 - February 1, 2013

  45. XANES Short Course: Theory, Analysis, Applications

    November 8-10, 2012

  46. X9 SAXS Workbench

    September 20-23, 2012

  47. Rock & Cell: From the Meso- to the Nanoscale with X-ray Spectromicroscopy

    September 17-18, 2012

  48. X9 SAXS Workbench

    June 21-24, 2012

  49. Crystallography Workbench

    June 11-13, 2012

  50. Synchrotron Radiation in Art and Archaeology

    June 5-8, 2012

  51. Synchrotron Radiation in Art and Archaeology (SR2A)

    June 5-8, 2012

  52. 2012 NSLS/CFN Joint Users' Meeting

    May 21-23, 2012

  53. Operando IV

    4th International Congress on Operando Spectroscopy

    April 29 - May 3, 2012

  54. 4th International Congress on Operando Spectroscopy

    April 29 - May 3, 2012

  55. Joint InSynC-INCREASE Workshop

    April 18-19, 2012

  56. X6A Workbench: Hands-on Synchrotron Structural Biology

    March 27-30, 2012

  57. X9 SAXS Workbench

    March 8-10, 2012

  58. XAFS Short Course: Introduction to the Experiment, Data Analysis and Modeling

    November 3-5, 2011

  59. X9 SAXS Workbench

    October 13-16, 2011

  60. Photon Sciences Users' Executive Committee and Town Meetings

    August 12, 2011

  61. Materials Diffraction Suite Workshop

    July 18-20, 2011

  62. 2011 NSLS/CFN Users' Meeting

    May 23-25, 2011

  63. Workshop on Supercritical Carbon Dioxide-Materials Interactions

    March 21-23, 2011

  64. Advanced Topics in XAFS Data Modeling

    November 4-6, 2010

  65. EPICS Collaboration Meeting - Fall 2010

    October 7-14, 2010

  66. 2010 Joint NSLS and CFN Users Meeting

    May 24-26, 2010

  67. In Situ and Operando XAFS Experiments and Data Analysis

    October 22-24, 2009

  68. MX Frontiers at the One Micron Scale

    July 23-24, 2009

  69. The Experimental Program to Stimulate Competitive Research (EPSCoR) Review 2009

    July 20-23, 2009

  70. INCREASE Workshop

    Interdisciplinary Consortium for Research and Educational Access in Science and Engineering

    July 15-17, 2009

  71. International Workshop for New Opportunities in Hard X-ray Photoelectron Spectroscopy: HAXPES 2009

    May 20-22, 2009

  72. 2009 NSLS / CFN Users' Meeting

    May 18-20, 2009

  73. Applications of Synchrotron Techniques in Glass Research

    April 6-7, 2009