BNL Home
February 2019
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1

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

    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.

2

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3

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4

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5

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6

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7

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8

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

    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.

9

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10

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11

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12

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13

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14

There are no conferences scheduled at this time.

  1. NSLS-II Collquium

    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

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

    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.

16

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17

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18

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19

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20

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21

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22

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  1. FEB

    22

    Friday

    NSLS-II Friday Lunchtime Seminar

    12 pm, NSLS-II Bldg. 743 Room 156

    Friday, February 22, 2019, 12:00 pm

    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.

23

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24

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25

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26

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27

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28

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  1. FEB

    22

    Friday

    NSLS-II Friday Lunchtime Seminar

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

    Presented by Selina Tenzer, University of Hohenheim, Germany

    12 pm, NSLS-II Bldg. 743 Room 156

    Friday, February 22, 2019, 12:00 pm

    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.

  2. MAR

    14

    Thursday

    NSLS-II Colloquium

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

    Presented by Bruce Eric Carlsten, Los Alamos National Laboratory

    4 pm, Large Seminar Room, Bldg. 510

    Thursday, March 14, 2019, 4:00 pm

    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.

  3. APR

    11

    Thursday

    NSLS-II Colloquium

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

    Presented by Kenneth Farley, Caltech

    4 pm, Large Seminar Room, Bldg. 510

    Thursday, April 11, 2019, 4:00 pm

    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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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

  14. 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).

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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)

  21. 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.

  22. 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

  23. Summer Sundays

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

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

  24. 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

  25. 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

  26. 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

  27. 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

  28. 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.

  29. NSLS-II Friday Luncheon Seminar

    "Macromolecular Interactions in Polymer-based Complex Fluids"

    Presented by Sudipta Gupta, Louisiana Consortium for Neutron Scattering, Department of Chemistry, Louisiana State Univ, Baton Rouge, LA

    Friday, April 20, 2018, 12 pm
    NSLS-II Bldg. 743 Rm 156

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

  30. NSLS-II Friday Lunchtme Seminar Series

    "SMI Beamline Status Update"

    Presented by Mikhail Zhernenkov, NSLS-II

    Friday, April 13, 2018, 12 pm
    NSLS-II Building 743 Room 156

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

  31. NSLS-II Friday Lunchtime Seminar

    "Interactive Ray-Tracing in XRT Code"

    Presented by Roman Chernikov, Canadian Light Source

    Friday, April 13, 2018, 12 pm
    NSLS-II Bldg. 743 Room 156

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

  32. NSLS-II Colloquium Series

    "Sustainable chemical energy storage: critiques and crystallography"

    Presented by William (Bill) David, University of Oxford, United Kingdom

    Thursday, April 12, 2018, 4 pm
    Physics Bldg. 510 Large Seminar Room

    Hosted by: John Hill

    Our increasing dependence on intermittent renewable energy production places a greater focus on the development of novel, affordable energy storage. The recent emphasis on electrochemical storage, and on lithium batteries in particular, addresses a significant component of our future energy storage requirements but future low-carbon energy scenarios must utilise a broad range of storage options. This talk will focus on several examples the underline the role that synchrotron X-ray and neutron powder diffraction can play in the understanding of both electrochemical and chemical energy storage systems.

  33. NSLS-II Friday Lunchtime Seminar Series

    "ISR Beamline Status Update"

    Presented by Christie Nelson, NSLS-II

    Friday, April 6, 2018, 12 pm
    NSLS-II Bldg. 743 Rm 156

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

  34. NSLS-II Friday Lunchtime Seminar Series

    "Automated robot based systems for crystallography on beamlines and in laboratories: developments performed on FIP-BM30A at the ESRF"

    Presented by Jean-Luc Ferrer, IBS, Grenoble, France

    Friday, March 30, 2018, 12 pm
    NSLS-II Bldg. 743 Rm 156

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

  35. NSLS-II Friday Lunchtime Seminar Series

    "ESM Beamline Status Update"

    Presented by Elio Vescovo, NSLS-II

    Friday, March 30, 2018, 12 pm
    NSLS-II Bldg. 743 Rm 156

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

  36. NSLS-II Friday Lunchtime Seminar Series

    "Design and Initial Commissioning Results for SIX, the Soft Inelastic X-ray Scattering Beamline"

    Presented by Joseph Dvorak, NSLS-II

    Friday, March 23, 2018, 12 pm
    NSLS-II Bldg. 743 Rm 156

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

  37. NSLS-II Friday Lunchtime Seminar Series

    "SR tomographic imaging studies at the ESRF"

    Presented by Paul Tafforeau, ESRF, France

    Friday, March 9, 2018, 12 pm
    NSLS-II Bldg. 743 Room 156

    Hosted by: Ben Ocko, Shirish Chodankar, Milinda Abeykoon, Juergen Thieme and Guimei Wang

  38. NSLS-II Friday Lunchtime Seminar Series

    "Probing crystal structures of complex materials using the atomic Pair Distribution Function"

    Presented by Milinda Abeykoon, NSLS-II

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

    Hosted by: Ben Ocko, Shirish Chodankar, Milinda Abeykoon, Juergen Thieme and Guimei Wang

  39. NSLS-II Friday Lunchtime Seminar Series

    "Using X-ray Fluorescence Microprobe to Elucidate the Chemistry of Trace Elements in Soils and Plants"

    Presented by Ryan Tappero, NSLS-II

    Friday, February 23, 2018, 12 pm
    NSLS-II Bldg. 743 Rm 156

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

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

  1. JUN

    17

    Monday

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

    June 17-21, 2019

  2. JUN

    23

    Sunday

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

    June 23-28, 2019

  3. JUL

    1

    Monday

    Teacher Training: Exploring Proteins with a New Light

    July 1-3, 2019

  1. LiX Solution Scattering Workbench

    February 14-16, 2019

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

    November 6-8, 2018

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

    October 22-26, 2018

  4. NSLS-II Pair Distribution Function School 2018

    September 17-19, 2018

  5. 10th International Workshop on X-ray Radiation Damage to Biological Samples

    September 13-14, 2018

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

    June 24-28, 2018

  7. 2018 NSLS-II and CFN Users' Meeting

    May 21-23, 2018

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

    November 1-3, 2017

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

    October 30 - November 1, 2017

  10. 2017 NSLS-ll and CFN Users' Meeting

    May 15-17, 2017

  11. High-Brightness Synchrotron Light Source Workshop

    April 26-27, 2017

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

    November 2-4, 2016

  13. 14th International Conference on Surface X-ray and Neutron Scattering (SXNS14)

    July 10-14, 2016

  14. 2016 NSLS-ll and CFN Users' Meeting

    May 23-25, 2016

  15. Advanced Topics in XAFS Data Analysis and Modeling

    November 5-7, 2015

  16. 8th International Workshop on Infrared Microscopy and Spectroscopy using Accelerator Based Sources

    October 11-15, 2015

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

    October 1-2, 2015

  18. NSLS-II Strategic Planning Workshop

    September 24-25, 2015

  19. 23rd International Congress on X-ray Optics and Microanalysis (ICXOM23)

    September 14-18, 2015

  20. 12th International Conference on Synchrotron Radiation Instrumentation (SRI 2015)

    July 6-10, 2015

  21. 2015 NSLS-II & CFN Joint Users' Meeting

    May 18-20, 2015

  22. First Science at the ABBIX Beamlines

    April 21-22, 2015

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

    November 13-15, 2014

  24. NSLS "Last Light"

    September 30, 2014

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

    May 19-21, 2014

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

    October 1, 2013

  27. NSLS-II First-Experiments Workshop

    August 12-13, 2013

  28. NSLS and CFN Users' Meeting

    May 20-22, 2013

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

    May 8-10, 2013

  30. RapiData 2013

    April 21-26, 2013

  31. X6A Workbench: Hands-on Synchrotron Structural Biology

    January 28 - February 1, 2013

  32. XANES Short Course: Theory, Analysis, Applications

    November 8-10, 2012

  33. Synchrotron Radiation in Art and Archaeology (SR2A)

    June 5-8, 2012

  34. 2012 NSLS/CFN Joint Users' Meeting

    May 21-23, 2012

  35. Operando IV

    4th International Congress on Operando Spectroscopy

    April 29 - May 3, 2012

  36. X6A Workbench: Hands-on Synchrotron Structural Biology

    March 27-30, 2012

  37. Photon Sciences Users' Executive Committee and Town Meetings

    August 12, 2011

  38. Materials Diffraction Suite Workshop

    July 18-20, 2011

  39. 2011 NSLS/CFN Users' Meeting

    May 23-25, 2011

  40. Workshop on Supercritical Carbon Dioxide-Materials Interactions

    March 21-23, 2011

  41. Advanced Topics in XAFS Data Modeling

    November 4-6, 2010

  42. EPICS Collaboration Meeting - Fall 2010

    October 7-14, 2010

  43. 2010 Joint NSLS and CFN Users Meeting

    May 24-26, 2010

  44. In Situ and Operando XAFS Experiments and Data Analysis

    October 22-24, 2009

  45. MX Frontiers at the One Micron Scale

    July 23-24, 2009

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

    July 20-23, 2009

  47. INCREASE Workshop

    Interdisciplinary Consortium for Research and Educational Access in Science and Engineering

    July 15-17, 2009

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

    May 20-22, 2009

  49. 2009 NSLS / CFN Users' Meeting

    May 18-20, 2009

  50. Applications of Synchrotron Techniques in Glass Research

    April 6-7, 2009