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No events scheduled
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NSLS-II Friday Lunchtime Seminar
"Bragg-case X-ray dynamical diffraction propagator in physical optics simulator SRW: thin crystal phase retarders"
Presented by John P. Sutter, Diamond Light Source, United Kingdom
Friday, December 18, 2020, 12 pm
ZoomGovHosted by: Ignace Jarrige
John P. Sutter(a), Oleg Chubar(b), Alexey Suvorov(b), Christie Nelson(b) and Kawal Sawhney(a) (a)Diamond Light Source; (b)NSLS-II, Brookhaven National Laboratory, Abstract A Bragg-case X-ray dynamical diffraction propagator has already been integrated into the "Synchrotron Radiation Workshop" (SRW) physical optics simulation software package. Previous benchmarking tests on crystal monochromators assumed thicknesses many times the extinction length, for which transmission is negligible. This paper reports tests of this propagator applied to thin crystals in transmission. The chosen example is a phase retarder, which allows users to alter the polarization of an X-ray beam. Phase retarders are often applied to studies of solid-state materials with hard X-rays, which current medium-energy storage ring synchrotron sources typically produce only with linear polarization. Correct designs of phase retarders require the accurate determination of both the intensity and the phase of the diffracted wave in all polarization states. First, to approximate an incident plane wave, SRW is used to simulate the passage of a Gaussian beam of very large radius of curvature through the phase retarder. Then, the phase retarder's effects on a typical undulator beam are simulated and the results are compared. Because X-ray phase retarders are highly sensitive to angular alignment, tolerances in misalignment are also determined. SRW simulations are compared with experimental data from the Integrated In Situ and Resonant Hard X-ray Studies (ISR) beamline at NSLS-II. The design of phase retarders can therefore be optimized for X-ray beamlines that must combine variable polarization with focusing or other properties.
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NSLS-II Friday Lunchtime Seminar
"Traversing the "Devil's Staircase": Dynamic behavior of a frustrated antiferromagnet"
Presented by Adra (Tory) Carr, National High Magnetic Field Laboratory, Los Alamos National Laboratory
Friday, December 4, 2020, 12 pm
ZoomGovHosted by: Ignace Jarrige
In frustrated magnets, seemingly simple competition between spin interactions can create theoretically infinite complexity. The Axial Next-Nearest Neighbor Ising (ANNNI) model is a classic model of frustration in which frustration occurs between nearest-neighbor ferromagnetic (FM) interactions and next-nearest-neighbor antiferromagnetic (AFM) interactions along chains of Ising spins. When cooled below the Neel temperature, the system passes through a theoretically infinite number of 1st order phase boundaries, referred to as the "Devil's staircase" or "Devil's flower". In this talk, we will discuss experiments performed at CSX (23-ID-1) using X-ray Photon Correlation Spectroscopy (XPCS) to test the dynamic behavior of these Devil's Staircase systems and demonstrate how this technique is broadly useful to study the peculiar dynamics of frustrated antiferromagnets. In particular, the results and model support a counterintuitive result: with decreasing temperature, the dynamics become faster.
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NSLS-II Friday Lunchtime Seminar
"Structural studies of SARS-CoV-2 viral fusion inhibition peptides at NSLS-II"
Presented by Dale Kreitler, NSLS-II
Friday, November 20, 2020, 12 pm
ZoomGovHosted by: Ignace Jarrige
SARS-CoV-2 uses a common viral strategy for fusing the viral envelope with a host cell membrane. The resulting fusion event is paramount to the infection process and this common strategy is known as a type I viral fusion mechanism. The energetically unfavorable membrane fusion event is driven by a large conformational change of the spike protein that occurs when the spike protein comes into contact with its target receptor on the host cell surface. One possible way to prevent this viral fusion event involves disrupting this conformational change by blocking the formation of the 6 helix bundle complex formed by the spike protein with synthetic polypeptide inhibitors. In this talk I will discuss preliminary structures of these polypeptide inhibitors in complex with fragments of the SARS-CoV-2 spike protein that were obtained at NSLS-II during min-safe operations. These structures provide some insight into important design considerations for future generation of SARS-CoV-2 membrane fusion inhibitors.
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NSLS-II Friday Lunchtime Seminar
"The role of hard X-ray synchrotron characterization of additively manufactured metal and composite structures: enhancing processes, materials and performance"
Presented by Gary Halada, Stony Brook University, NY
Friday, November 13, 2020, 12 pm
ZoomGovHosted by: Ignace Jarrige
Focusing on current challenges in understanding the process/structure/properties/performance relationship in additively manufactured (3D printed) alloys and ceramics, this talk will outline the potential role of planned hard X-ray capabilities at NSLS II. In particular, the talk will include recent results from an ongoing study of the relationship of factors contributing to durability of laser powder bed fusion (LPDF) formed 316L stainless steel, the role of print-formed micro and nanostructural heterogeneities on surface and bulk properties, and recent X-ray studies of alloys designed for aerospace, energy infrastructure and biomedical applications. The potential for in situ and in operando studies of printing via laser melting/sintering and post-printing processing to decrease porosity, improve surface finish and mechanical properties, as well as in situ X-ray analysis during corrosion and thermomechanical testing, will enhance the value of AM for manufacturing and a wide variety of applications relevant to regional industry and commercial applications.
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NSLS-II Friday Lunchtime Seminar
"Investigation of Aqueous Electrochemical Energy Storage Mechanisms Utilizing Advanced Characterization Techniques"
Presented by Daniel Charles, University of New Hampshire
Friday, November 6, 2020, 12 pm
ZoomGovHosted by: Ignace Jarrige
Electrochemical energy storage (EES) has become prevalent in daily life for their use in mobile electronics and electric vehicles. More recently, the need for large-scale stationary energy storage to integrate clean and renewable alternative energy sources to the electric grid has arisen. Aqueous EES devices using beyond-lithium charge carriers offer an attractive solution to this problem because of their superior safety, lower cost, and excellent transport properties compared to their organic counterparts. However, improvements in energy density and cyclability are required for implementation. Fundamental research on the charge-storage mechanisms is critical to understanding the structure-function relationship and, thus, for the development of electrodes materials for aqueous EES. Characterization of these electrode materials using synchrotron and neutron techniques provide vital information on the crystalline and electronic structure. Furthermore, time-resolved in situ measurements offer detailed information on structural changes due to the intercalation/de-intercalation of cations and the evolution of the electronic state of metal components during redox reactions. This, coupled with half-cell and full-cell electrochemical measurements, provides valuable insight into the change-storage mechanisms that occur. In this work, advanced characterization techniques have been used to investigate the charge storage mechanisms of nanoscale transition metal oxide electrode materials for aqueous EES. Various types of electrochemical charge storage mechanisms (pseudocapacitive, intercalation, and phase-change) were studied. Numerous strategies for improving the energy density and cyclability have been employed, including; studying the promotional effects of structural water, inducing structural disorder, synthesizing materials with open frameworks, doping with more redox-active components, using multivalent cations as charge carriers, and expanding the available potential window. These results provide a pathway for designing the next generation of aqueous EES devices. ________________________________ Daniel S Charles, Xiaoqiang Shan, SaeWon Kim, Fenghua Guo, and Xiaowei Teng
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NSLS-II Friday Lunchtime Seminar
"Understanding the Instability of the Halide Perovskite CsPbI3 Through Temperature-Dependent Structural Analysis"
Presented by Daniel B Straus, Princeton University, NJ
Friday, October 30, 2020, 12 pm
ZoomGovHosted by: Ignace Jarrige
Daniel B. Straus, Shu Guo, AM Milinda Abeykoon, and R. J. Cava Despite the tremendous interest in halide perovskite solar cells, the structural reasons that cause the all-inorganic perovskite CsPbI3 to be unstable at room temperature remain mysterious especially since many tolerance factor-based approaches predict CsPbI3 should be stable as a perovskite. We use a solid-state method to synthesize single crystals of perovskite-phase CsPbI3 that are kinetically stable at room temperature, allowing us to characterize its bulk properties and rationalize its thermodynamic instability. Electronically, CsPbI3 does not behave like a conventional semiconductor because its optical absorption and joint density-of-states is greatest near the band edge and decreases beyond the band gap for at least 1.9 eV. Structurally, single-crystal X-ray diffraction measurements reveal that while Cs occupies a single site from 100 to 150 K, it splits between two sites from 175 to 295 K with the second site having a lower effective coordination number. This finding along with other structural parameters suggests that Cs rattles in its coordination polyhedron. Pair distribution function measurements reveal that on the length scale of the unit cell, the Pb-I octahedra concurrently become greatly distorted, with one of the I-Pb-I angles approaching 82° compared to the ideal 90°. The rattling of Cs, low number of Cs-I contacts, and high degree of octahedral distortion cause the instability of perovskite-phase CsPbI3. These results reveal the limitations of tolerance factors in predicting perovskite stability and provide detailed structural information that suggests methods to engineer stable CsPbI3-based solar cells.
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Virtual Symposium
"National Virtual Biotechnology Laboratory Symposium"
Wednesday, October 28, 2020, 11:30 am
Virtual - Registration requiredHosted by: John Hill
The symposium is a virtual event to highlight the impact the U.S. Department of Energy's (DOE) National Virtual Biotechnology Laboratory (NVBL) has had utilizing the unique capabilities of the DOE to tackle the science and technology challenges associated with COVID-19, and to discuss areas in which the NVBL can have impact in the future. With perspectives from Chris Fall, Director, Office of Science, DOE, and William A. Bookless, Principal Deputy Administrator of the National Nuclear Security Administration, the event will feature presentations from lead investigators reporting progress in: • Epidemiological modeling • Therapeutics • Testing • Understanding transport of the virus • Solving issues around supply chain challenges In addition, keynote speakers from outside the NVBL will discuss the upcoming science and technology needs in computing, testing and surveillance, and vaccines.
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NSLS-II Friday Lunchtime Seminar
"Local structural symmetry breaking at ambient conditions in FeSe superconductor"
Presented by Robert Koch, Condensed Matter Physics and Materials Science Dept
Friday, October 23, 2020, 12 pm
ZoomGovHosted by: Ignace Jarrige
We report pair distribution function measurements of the iron-based superconductor FeSe above and below the structural transition temperature. Structural analysis reveals a local orthorhombic distortion with a correlation length of about 4 nm at temperatures where an average tetragonal symmetry is observed. The analysis further demonstrates that the local distortion is larger than the global distortion at temperatures where the average observed symmetry is orthorhombic. Our results suggest that the low-temperature macroscopic nematic state in FeSe forms from an imperfect ordering of orbital-degeneracy-lifted nematic fluctuations which persist up to at least 300 K.
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NSLS-II Friday Lunchtime Seminar
"Structure-based drug development for COVID-19"
Presented by Desigan Kumaran & Babak Andi, Biology & NSLS-II
Friday, October 16, 2020, 12 pm
ZoomGovHosted by: Ignace Jarrige
The recent outbreak of coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 in December 2019 posed great threats to public health and attracted enormous attention around the world. The morbidity and mortality rates associated with COVID-19 in the United States and Europe are increasing exponentially. To date, there are no clinically approved vaccines or antiviral drugs available for these COVID-19 infections and hence there is urgent demand for effective therapeutics and vaccines to control and eradicate the pandemic. We are using structure-based drug discovery (SBDD) approach to develop anti-COVID-19 drugs by targeting multiple viral targets. In order to ramp up the discovery process, we are screening FDA approved drugs with special attention to other existing antiviral and pathogen-specific drugs. Indeed, we have identified few FDA approved drugs that can inhibit (with moderate potency) one of the SARS-CoV-2 viral protein, main protease (Mpro), which play a key role in the viral replication cycle. In this presentation, we will highlight our efforts on SBDD approach on Mpro as a representative target that includes viral protein production, molecular docking studies, in-vitro binding assay and the co-crystal structure determination.
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NSLS-II Friday Lunchtime Seminar
"Provenance and workflow tools for multimodal experiments"
Presented by Line Pouchard, Computational Science Initiative, BNL
Friday, September 25, 2020, 12 pm
ZoomGovHosted by: Ignace Jarrige
New data management techniques are needed to address the increasing volume and complexity of data produced by the latest generation of detectors at Scientific User Facilities such as NSLS-II. The experiments carried out by very diverse user communities produce data processed in many unique and highly customized scientific workflows. The facilities exhibit further complexity in large and adaptable collections of instruments, broad ranges of data rates, and data access patterns. In addition, multi-modal techniques that characterize samples with different imaging modalities are poised to further increase the heterogeneity of data processing and analysis methods. One particular challenge is the development of collections of well-annotated datasets for use with machine learning techniques, including provenance. Provenance is the detailed recording of data lineage and software processes operating on data that enable interpreting, validating and reproducing results. This seminar will describe provenance and workflow tools developed by a joint NSLS-II-CSI team under LDRD, including a text mining portal classifying scientific literature papers by XAS edges, and a graph-based provenance wrapper developed for XPD and recently matured to run with a 3D reconstruction code.
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NSLS-II Friday Lunchtime Seminar
"Reversible Room-Temperature Fluoride-Ion Insertion in a Tunnel-Structured Transition Metal Oxide Host"
Presented by Wasif Zaheer, Texas A&M University, TX
Friday, September 18, 2020, 12 pm
ZoomGovHosted by: Ignace Jarrige
An energy storage paradigm orthogonal to Li-ion battery chemistries can be conceptualized by employing anions as the primary charge carriers. F-ion conversion chemistries show promise but have limited cyclability as a result of the significant change in volume of active electrodes upon metal−metal fluoride interconversion. In contrast, the exploration of insertion chemistries has been stymied by the lack of hosts amenable to reversible F-ion insertion at room temperature. In this study, we showed reversible and homogeneous topochemical insertion/deinsertion and bulk diffusion of F ions within the one-dimensional tunnels of sub-micrometer-sized FeSb2O4 particles at room temperature. The insertion of F ions is evidenced by formal oxidation of the iron centers from Fe2+ to Fe3+ with a lattice volume contraction of
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NSLS-II Friday Lunchtime Seminar
"Spin-charge Higgs mode in bilayer iridates"
Presented by Mark Dean, CMPMSD / BNL
Friday, August 28, 2020, 12 pm
via Zoom - contact: nsls2user@bnl.govHosted by: Ignace Jarrige
Spontaneous symmetry breaking at phase transitions is one of the richest topics in physics describing situations as diverse as magnetism, through freezing, to how elementary particles acquire mass. Phase transitions can be classified into two categories based on whether the phase or the amplitude of the order parameter softens at the transition. In particle physics, both types of transition are well-known and termed either Nambu–Goldstone modes or Higgs Bosons for phase and amplitude modes, respectively. In insulating magnets, order is overwhelmingly conceptualized in terms of phase (i.e. Nambu–Goldstone) softening. In this talk, I will describe our resonant inelastic x-ray scattering (RIXS) experiments which reveal a Higg's amplitudon mode in bilayer magnetic Sr3Ir2O7. We attribute this mode to spin-charge coupled excitations arising from the narrow Mott-gap in this insulator. The material's proximity to a quantum critical point softens the amplitudon to excitation energies only sightly above the phase mode, allowing an active engagement of the mode in the magnetic phase transition. Our work provides a new solid-state platform for research on the dynamics of the Higgs mode and a means to understand novel magneto-transport in moderately correlated magnets.
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NSLS-II Friday Lunchtime Seminar
"Phyllosilicates and X-ray amorphous materials on Earth and Mars, characterization with synchrotron radiation"
Presented by Michael T. Thorpe, NASA Johnson Space Center, Houston, TX
Friday, August 21, 2020, 12 pm
ZoomGovHosted by: Ignace Jarrige
Phyllosilicates and secondary X-ray amorphous materials have the unique ability to record a history of sedimentary processing and the environmental conditions during their formation. These materials are abundant in Martian sedimentary rocks, as identified from the CheMin instrument on the Curiosity rover. However, their atomic structures lack long-range order, making them difficult to characterize with CheMin and laboratory instruments. Synchrotron radiation provides a state-of-the-art technique to characterize the structure and composition of these juvenile alteration products. Using sediments from the basaltic terrains of Iceland , we seek to understand how the composition and short-range atomic order of secondary phases evolve from source to sink.
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Summer Sundays
"National Synchrotron Light Source II"
Sunday, August 16, 2020, 3:30 pm
VirtualTune in to get an up-close look at the "beamlines" where scientists use ultrabright x-ray light to see the atomic structure of batteries, proteins, and more. Then, viewers will have the opportunity to pose questions to a panel of scientists.
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NSLS-II Friday Lunchtime Seminar
"Use of synchrotron X-ray footprinting to reveal allosteric changes in a key plant metabolic enzyme"
Presented by Rohit Jain, Case Western Reserve University, OH
Friday, August 7, 2020, 12 pm
ZoomGovHosted by: Ignace Jarrige
X-ray footprinting (XFP) is a tried-and-true method for probing macromolecule structure in solution. In XFP, hydroxyl radicals produced by X-ray radiolysis covalently label protein side chains and cleave phosphodiester backbones of nucleic acids, providing insight into macromolecular structure and dynamics that complements data obtained from crystallography, cryo-EM, and small-angle X-ray scattering. XFP beamline (17-BM) at NSLS-II uniquely provides unmatched photon flux density and high level of automation to help resolve challenging biophysical questions, not obtainable by other structural probes. Recent developments in mass spectrometry have advanced the structural analysis and can provide detailed sub-peptide and residue level information for protein footprinting studies. In this talk, we will illustrate the use of synchrotron X-ray footprinting technique for studying structural changes in KIN10 enzyme, a key plant metabolic enzyme, after binding to its phosphorylated disaccharide ligand.
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NSLS-II Friday Lunchtime Seminar
"Quantum materials meet coherent x-rays"
Presented by Xiaoqian Chen, NSLS-II
Friday, July 31, 2020, 12 pm
Zoom InvitationHosted by: Ignace Jarrige
Quantum materials are a class of materials whose properties are deeply rooted in quantum mechanical processes. A few examples include unconventional superconductors and magnets, topological insulators, and multiferroics. Phase nonuniformity and dynamics in quantum materials play a crucial role in deciding their ground states. This calls for a microscopic tool that is also sensitive to a wide range of dynamical time scales. In this talk, I will discuss why synchrotron coherent x-rays are an ideal tool. I will review recent developments in this field with an emphasis on the speckle correlation analysis performed at NSLSII, and discuss some future topics to explore.
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NSLS-II Friday Lunchtime Seminar
"New opportunities for IXS at the GALAXIES beamline, Synchrotron SOLEIL"
Presented by J-P. Rueff, Synchrotron SOLEIL, France
Friday, July 24, 2020, 12 pm
Zoom InvitationHosted by: Ignace Jarrige
The GALAXIES undulator beamline at Synchrotron SOLEIL is dedicated to inelastic x-ray scattering (IXS) and high energy photoemission (HAXPES) spectroscopy in the tender x-ray range (2.3 – 12 keV) [1]. We will present recent scientific results illustrating the capabilities of the IXS endstation at GALAXIES with an emphasis on extreme conditions [2,3] and x-ray Raman spectroscopy [4]. Ongoing instrumental developments for improved energy resolution, faster acquisition scheme and larger collection angle will be discussed. Finally, we will explore the new possibilities offered by the future SOLEIL Upgrade program. [1] Rueff et al., J. Synchrotron Rad. 22 (2015), 175 [2] Lebert et al., PNAS 116 (2019), 20280 [3] Mazzone et al., Phys. Rev. Lett. 124 (2020), 125701 [4] Georgiou et al., Science Advances 5 (2019), eaaw5019
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NSLS-II Friday Lunchtime Seminar
"Characterization of Lithium & Sodium Batteries using Synchrotron X-ray Techniques at NSLS II"
Presented by Zulipiya Shadike, BNL / Chemistry Department
Friday, July 10, 2020, 12 pm
via Zoom - contact: nsls2user@bnl.govHosted by: Ignace Jarrige
The utilization of anion redox reaction is opening a new approach to increase rechargeable capacities in alkaline ion batteries recently. It is important to understand the oxidation state and electronic structure of anion in the electrodes at different state of charge. Herein, we designed and synthesized the O3-NaCr2/3Ti1/3S2 (NCTS) material, which is delivering a high capacity of 190 mAh g-1 (0.95 Na+) as a cathode for sodium battery based on the cation and anion redox processes. To study the underlying nature of anionic redox chemistry in this layered chalcogenide, we investigated the charge compensation mechanism and structure evolution of NCTS electrode using multi-model synchrotron x-ray techniques and scanning transmission electron microscopy. Our experimental results provided core evidence to reveal various charge compensation mechanisms, involving the formation of electron holes, anionic dimers, and disulfide-like species. These results provide a new insight to clarify the nature of anionic redox process of layered chalcogenides, which is important for the development of novel cathode materials with high energy density.
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NSLS-II Friday Lunchtime Seminar
"Structural biology in drug discovery: Development of viral protease inhibitors"
Presented by Scott Lovell, University of Kansas, KS
Friday, June 12, 2020, 12 pm
via Zoom - contact: nsls2user@bnl.govHosted by: Ignace Jarrige
X-ray crystallography is a widely utilized technique to provide essential high resolution structural information for proteins and is particularly important to determine inhibitor binding modes for drug development. Modern advances in protein crystallization automation, synchrotron X-ray beamlines and crystallographic software development have enabled the rapid determination of crystal structures which has greatly facilitated drug discovery and development projects. Diffraction data for dozens of protein-inhibitor samples can be collected in a matter of hours and immediately analyzed for inhibitor binding using automated crystallographic software pipelines. As such, information regarding the binding modes of various inhibitors can be quickly obtained which facilitates subsequent optimization. Application of these modern structural biology techniques has been critical to the advancement of ongoing collaborative projects focused on the development of covalent inhibitors that target the 3CL proteases of Norovirus, MERS-CoV, SARS-CoV and SARS-CoV-2.
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NSLS-II Friday Lunchtime Seminar
"Correlating microscopic materials properties with superconducting qubit performance"
Presented by Anjali Premkumar, Department of Electrical Engineering, Princeton University
Friday, June 5, 2020, 12 pm
via Zoom - contact: nsls2user@bnl.govHosted by: Ignace Jarrige
In recent years, evidence has emerged that superconducting qubit performance is limited by imperfections in constituent materials. To characterize the microscopic character of these imperfections, we performed measurements of qubit lifetimes in parallel with structural and electron microscopy of the niobium films used in qubit fabrication. Correlations were found between qubit relaxation times and several materials properties, including grain size, oxide composition on the surface and within grain boundaries, and residual resistance. These findings represent a novel approach to understanding sources of qubit decoherence, utilizing techniques such as hard x-ray photoelectron spectroscopy and transmission electron microscopy.
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NSLS-II Friday Lunchtime Seminar
"Understanding the improved cycling performance of sulfurized polyacrylonitrile cathode in Li-S battery"
Presented by Seongmin Bak, Chemistry Division, Brookhaven National Laboratory
Friday, May 29, 2020, 12 pm
via Zoom - contact: nsls2user@bnl.govHosted by: Ignace Jarrige
The demands on low cost and high energy density rechargeable batteries for both transportation and large-scale stationary energy storage are stimulating more research toward new battery systems such as metal, metal-sulfur, metal-air, and multivalent batteries. Since sulfur is an earth-abundant material with low cost and has a high theoretical capacity, Li-S battery chemistry has attracted significant interest during the past decade. The Li-S battery utilizes electrochemical conversion of sulfur (S8) to lithium sulfide (Li2S), going through multiple electron transfer processes associated with long- and short-chain polysulfide (Li2Sx) intermediates. It is well known that the long-chain polysulfides can be dissolved into electrolyte with aprotic organic solvents and migrated to the Li anode side. This so-called "shuttle effect" is considered as the main reason for the capacity loss and low coulombic efficiency of the Li-S system. A lot of efforts have been made on how to overcome the problem of polysulfide dissolution through new sulfur-based material and electrolyte, as well as cell engineering. Sulfurized polyacrylonitrile (SPAN) is a promising material capable of suppressing polysulfide dissolution in Li-S batteries with carbonate-based electrolytes. However, undesirable spontaneous formation of soluble polysulfides may arise in the ether-based electrolyte, and the conversion of sulfur in SPAN during the lithiation/delithiation process is yet to be understood clearly. In this talk, our recent characterization study on the SPAN cathode material in Li-S battery using spatially-resolved X-ray fluorescence (XRF) microscopy combined with X-ray absorption spectroscopy (XAS) will be present. The morphology changes and the redistribution of sulfur and polysulfide in both the SPAN cathode and lithium metal anode were monitored through the XRF images, while the chemical state changes of SPAN and sulfur-containing interfacial layer (i.
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NSLS-II Friday Lunchtime Seminar
"Catalysis with XAFS and XPS at the Brazilian synchrotron: examples and perspectives"
Presented by Daniela Coelho de Oliveira, LNLS, Brazil
Friday, March 6, 2020, 12 pm
NSLS-II Bldg. 743 Room 156Hosted by: Ignace Jarrige
In this talk, I will present some recent results of catalysts characterization obtained at the Brazilian synchrotron using XAS and/or XPS . I will show a brief perspective of the new capabilities that are planned to attend the catalysis community as well as other research areas.
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