Dr
Davide Ferri
(Empa)
05/07/2012, 10:30
Catalysis
Poster contribution
In situ DRIFTS and XAS are two complementary techniques in catalysis, allowing a deeper insight into reaction mechanisms and the dynamic of redox processes. However, XAS provides only bulk information due to the penetration depth of X-rays. The combination with modulated excitation spectroscopy (MES) through periodic switch of gas composition, and phase sensitive detection (PSD), has...
Ms
Desiree Heintz
(DESY-Hasylab)
05/07/2012, 10:30
Biological / Pharmaceutical Research
Poster contribution
Oxidation state changes of metal organic complexes play an important role in many chemical and biological processes. X-ray absorption near edge spectroscopy (XANES) is a powerful tool to follow these changes since it can directly probe the oxidation state of a metal center[1]. However, X-rays themselves are known to cause photoreduction in photosensitive samples[2, 3,]. In order to reduce...
Mr
Daniel Peitz
(Paul Scherrer Institut)
05/07/2012, 10:30
Catalysis
Poster contribution
Selective catalytic reduction (SCR) of nitrogen oxides (NOx) with ammonia (NH3) is a common method in emission control. Mobile SCR systems inject aqueous urea solution (AdBlue®) into the hot exhaust gas to catalytically decompose it to NH3.
However, AdBlue® shows poor temperature stability in cold or hot climates. In contrast, Guanidinium formate (GuFo) solutions can be stored between -30 and...
Dr
Achim Stocker
(Uni Bern)
05/07/2012, 10:30
Biological / Pharmaceutical Research
Poster contribution
11-cis-retinal is the photon accepting cofactor of rhodopsin in the primary light reaction within rod- and cone receptor cells. Persistent vision affords the enzymatic re-isomerization of accumulating all-trans-retinal to 11-cis-retinal in the retinal pigment epithelium (RPE). Cellular retinaldehyde binding protein (CRALBP) is essential for vision by routing 11-cis-retinoids for the conversion...
Dr
Pawel Grochulski
(Canadian Light Source)
05/07/2012, 10:30
Biological / Pharmaceutical Research
Poster contribution
The Canadian Macromolecular Crystallography Facility (CMCF) is composed of two beamlines, 08ID-1 and 08B1-1. The 08ID-1 beamline is a highly-specialized protein crystallography beamline suitable for collecting diffraction data from small crystals of macromolecules and crystals with large unit cell dimensions. It is equipped with a Roentec fluorescence detector which allows X-ray absorption...
Dr
Andrei Khodakov
(UCCS, CNRS, Université Lille 1, ENSCL, Ecole Centrale de Lille)
05/07/2012, 10:30
Catalysis
Poster contribution
Biosyngas obtained from biomass gasification can be used to produce clean hydrocarbon fuels by Fischer-Tropsch reaction (FT). H2/CO ratio in biosyngas could be adjusted if water gas shift reaction may occur simultaneously with FT synthesis. Cobalt and iron bimetallic catalysts are active in these two reactions. The present work focuses on in-situ and operando studies of iron and cobalt phases...
Dr
Anja Burkhardt
(DESY)
05/07/2012, 10:30
Biological / Pharmaceutical Research
Poster contribution
Protein crystals can contain up to 90% of solvent (mainly water). Cryocooling of such crystals requires cryoprotectants like glycerol or ethylene glycol to suppress hexagonal ice formation and convert the water to amorphous ice (vitrification). Finding ideal cryoconditions can be very time and crystal consuming. Moreover, the crystal quality is often degraded upon cryocooling even if adequate...
Dr
Maksym Yarema
(Eidgenössische Technische Material Prüfungsanstalt, Dübendorf)
05/07/2012, 10:30
Materials / Nanomaterials
Poster contribution
We present cost-effective and fast solution-processed synthesis of metallic and metal alloy nanocrystals with accurate size and composition control. In particular, we prepare Bi, In, In(1-x)Snx, Sn, and Ga nanocrystals. The average size of nanocrystals can be tuned in wide range for each material by means of reaction parameters: growth temperature, time, and precursor concentrations....
Mr
atul kumar
(IGIB)
05/07/2012, 10:30
Biological / Pharmaceutical Research
Poster contribution
As many as 29 post- translational modifications in 16S and 23S ribosomal RNA of Escherichia coli are known; 10 of which are located in the 16S RNA and 19 are present in 23S RNA. These modifications are brought about by specific methyltransferases. Nine of ten methylated nucleotides of Escherichia coli 16 S rRNA are conserved in Mycobacterium tuberculosis. All the 10 different...
H. Carvalho
(Institute of Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, Engesserstr.20, 76131 Karlsruhe, Germany)
05/07/2012, 10:30
Catalysis
Poster contribution
Ms
Renata Bessa Duarte
(ETH Zurich)
05/07/2012, 10:30
Catalysis
Poster contribution
The role of Sm2O3 and CeO2 promoters on the structural properties and catalytic behavior of 0.5 wt% Rh/xSm2O3-yCeO2-Al2O3 catalysts during methane steam reforming (MSR) was investigated by in situ X-ray absorption spectroscopy and other characterization methods. Catalytic tests were performed at 773 and 1033 K. The combination of XAS measurements with mass spectrometer provided a way to...
Dr
Igor Bezverkhyy
(ICB CNRS University of Burgundy)
05/07/2012, 10:30
Catalysis
Poster contribution
Hydrogen sulfide is a strong catalytic poison and its complete removal from gaseous streams is of key importance for successful industrial implementation of emerging technologies like low-temperature fuel cells (PEMFC) or Fischer-Tropsch synthesis. Currently the most successful approach to deep desulfurization (< 0.1 ppm S) relies on a gas-solid reaction between H2S and ZnO- based sorbents....
Dr
David von Stetten
(ESRF)
05/07/2012, 10:30
Materials / Nanomaterials
Poster contribution
ID29 is an ESRF undulator beamline with a routinely accessible energy
range of between 20.0 keV and 6.0 keV dedicated to the use of
anomalous dispersion techniques in macromolecular crystallography.
Since 2009 it became the home to the ESRF Cryobench facility, ID29S. In order to take advantage of their close location a novel on-line setup has been developed and commissioned. It will permit...
Dr
David Baudouin
(Post doctorate)
05/07/2012, 10:30
Catalysis
Poster contribution
The preparation of Ni nanoparticles smaller than 2-3 nm still remains a challenge today. Yet, using a colloidal approach for the synthesis of Nickel-Silane based nanoparticles, [NixSi-C8H17], we successively prepared silica supported nickel NPs having a size of 1.3±0.2 nm, corresponding to a dispersion of 71±5 %. XAS and in situ liquid NMR indicated that the initial colloidal nanoparticles...
Dr
Cristina Paun
(Institute for Chemical and Bioengineering ETH Zurich, 8093 Zurich, Switzerland), Dr
Olga Safonova
(Paul Scherrer Institut, 5232 Villigen, Switzerland)
05/07/2012, 10:30
Catalysis
Poster contribution
Oxygen storage capacity (OSC) is a unique property of ceria (CeO2) allow-ing this oxide to store oxygen in its structure and provide it for catalytic processes under reducing conditions [1]. This property is extensively used in exhaust catalysis. The surface oxygen in ceria is much more active com-pared to the bulk one and its activity can be further enhanced by addition of noble metals (Pt,...
Dr
Åsmund Kjendseth Røhr
(University of Oslo, Norway)
05/07/2012, 10:30
Biological / Pharmaceutical Research
Poster contribution
Considering that more than one thousand structures in the Protein Data Bank contain flavin cofactors (1), it is of interest to verify the flavin geometry and electronic state when using these structures for deducing reaction mechanisms and when analyzing the conformational interplay between the cofactor and its protein scaffold. Inspecting flavin structure with QM/MM methods and monitoring of...
Dr
Martin R. Fuchs
(Paul Scherrer Institute)
05/07/2012, 10:30
Biological / Pharmaceutical Research
Poster contribution
The new unified diffractometer for the three macromolecular crystallography beamlines of the Swiss Light Source (SLS) – the D3 – has recently been installed at beamline X10SA.
A core component of this new endstation is the on-axis micro-spectrophotometer MS3 for microscopic sample imaging with one micron image resolution. For combined spectroscopy and diffraction measurements, its multi-mode...
Dr
Sonia Pin
(Paul Scherrer Institut - ENE department)
05/07/2012, 10:30
Catalysis
Poster contribution
Above or near the critical point (374 °C, 22.1 MPa) the behavior of water as a solvent is entirely reversed. Organic compounds become completely miscible with supercritical water, whereas inorganic salts precipitate. This is of particular interest for several disciplines and technological applications, i.e. geochemistry, hazardous waste treatments and Synthetic Natural Gas (SNG) production....
22.
Nitrous oxide reductase with a unique [4Cu:2S] centre from the denitrifying Pseudomonas stutzeri
Mrs
Anja Wuest
(Albert-Ludwigs-Universität Freiburg, Institut für Organische Chemie und Biochemie, workgroup Oliver Einsle)
05/07/2012, 10:30
Biological / Pharmaceutical Research
Poster contribution
Denitrification is the microbiological reduction of nitrate via nitrite, nitric oxide and nitrous oxide, followed by the subsequent two-electron reduction of nitrous oxide to dinitrogen.
Nitrous oxide reductase, NosZ, is a dimeric multi-copper protein with 638 residues per subunit and the reported Cu content depends on the purification strategy. Because of the sensitivity of the enzyme...
Mr
Qasim Imtiaz
(ETH Zurich)
05/07/2012, 10:30
Materials / Nanomaterials
Poster contribution
Chemical looping combustion (CLC) is one of the most promising CO2 capture processes. Copper oxide is an attractive candidate as oxygen carrier for CLC owing to its (i) exothermic reduction reactions, (ii) fast kinetics in both the reduction and oxidation reactions and (iii) low tendency for carbon deposition. To evaluate the potential of Cu-based oxygen carriers for CLC, the redox pathways of...
Mr
Andrea Pica
(Dept Chemical Sciences, University of Naples "Federico II")
05/07/2012, 10:30
Biological / Pharmaceutical Research
Poster contribution
Despite the high physiological relevance, hemoglobin crystal structures with NO bound to heme are less than 1% of the total ligated hemoglobins (Hbs) deposited in the Protein Data Bank. One of the major difficulties in obtaining nitrosyl-ligated Hbs is probably related to oxidative denitrosylation, being nitrosylated species very reactive toward O2. Raman-assisted crystallography can be a...
Dr
Paula Abdala
(SNBL at ESRF), Dr
Wouter van Beek
(SNBL at ESRF)
05/07/2012, 10:30
Catalysis
Poster contribution
The Swiss Norwegian Beamlines at the ESRF have been equipped with a permanent online Raman Spectrometer in June 2007. The Raman spectrometer serves two experimental stations operating in parallel. High Resolution Powder Diffraction, EXAFS combined with on-line Raman spectrometry has become routine. Many experiments are profiting from the possibilities for rapid changeovers from powder...
Dr
Anna Pallo
(Hungarian Academy of Sciences, Budapest, Hungary)
05/07/2012, 10:30
Biological / Pharmaceutical Research
Poster contribution
IPMDH is essential for leucine biosynthesis in bacteria and plants catalysing the oxidation of 3-isopropylmalate (IPM) to 2-oxo-isocaproate by NAD in the presence of Mn2+. Single crystal microspectrometry has shown that in crystals of IPMDH*Mn*IPM and of IPMDH*Mn*NAD the diffusion of the other substrate (respectively NAD or IPM) causes the appearance of the NADH band. The reaction might be...
Mr
Peter Bleith
(Paul-Scherrer-Institute)
05/07/2012, 10:30
Materials / Nanomaterials
Poster contribution
LiCoO2 is today’s standard cathode material for Li-ion batteries. Li2MnO3∙Li(NixCoyMnz)O2 (NCM) is a very promising candidate to replace LiCoO2 since it shows an approx. 2 times higher specific charge and is less expensive. We investigated the structural changes of NCM upon charge and discharge with ex situ neutron diffraction, in situ X-ray diffraction, and in situ Raman spectroscopy.
The...
Dr
Guillaume Beutier
(CNRS)
05/07/2012, 10:30
Materials / Nanomaterials
Poster contribution
Reflections forbidden by crystallographic rules can be observed when the energy of incident x-rays is tuned to an absorption edge of the material. When the site symmetry of the resonant atoms is such that dipole-dipole resonant scattering is also forbidden, one can still measure intensity at the position of the forbidden reflection: it is related to the transcient atomic displacements of the...
Dr
Antonio Cervellino
(Paul Scherrer Institut)
05/07/2012, 10:30
Materials / Nanomaterials
Poster contribution
The Materials Science beamline - Powder station of the Swiss Light Source synchrotron is equipped with a state-of-the-art Mythen II detector, designed for simultaneous acquisition of up to 2X30720 channels covering 120 deg with 0.0037 deg resolution with double-layer sensors for higher efficiency at high energies; a second detector placed at up to 5 m from the sample allows the simultaneous...
Julia Melke
(Karlsruher Institute of Technology)
05/07/2012, 10:30
Materials / Nanomaterials
Poster contribution
Due to the growing awareness of environmental concerns and the threat of depleting conventional fossil energy resources, low emission renewable energy processes are required. The key technologies for the energy economy of the 21st century are electrochemical energy conversion and storage technologies, like fuel cells ,lithium ion and redox flow battery systems. Although the mentioned systems...
Dr
Ronny Wirz
(Bruker Optics)
05/07/2012, 10:30
Materials / Nanomaterials
Poster contribution
In the 1970´s of the last century attempts to use the advantage of the bright and highly collimated e-synchrotron radiation (SR) not only in the short wavelength (UV, X-Ray) but also in the long wavelength ranges (typically 4000 to 10cm-1) of the electromagnetic
spectrum were unsuccessful. The theoretically expected advantage of
the synchrotron radiation as bright but expensive IR source...
Dr
Elena Nazarenko
(Gothenburg University)
05/07/2012, 10:30
Poster contribution
We report the X-ray absorption spectroscopy studies of the Cu and Fe edges of the cytochrome bo3 quinol oxidase from Escherichia coli at the room temperature. Heme-copper oxidases are integral membrane proteins in which proton pumping takes place. Most proposed proton-pumping mechanisms involve CuB and its histidine ligands. The existence and identity of such reorganization of the CuB geometry...
