Search results for "X-Ray"
showing 10 items of 4234 documents
Production, crystallization and preliminary X-ray analysis of the human integrin alpha1 I domain.
1999
Integrin α1β1 is one of the main collagen receptors in many cell types. A fast large-scale production, purification and crystallization method for the integrin α1 I domain is reported here. The α1 I domain was crystallized using the vapour-diffusion method with a reservoir solution containing a mixture of PEG 4000, sodium acetate, glycerol and Tris–HCl buffer. The crystals beong to the C2 space group, with unit-cell parameters a = 74.5, b = 81.9, c = 37.3 Å, α = γ = 90.0, β = 90.8°. The crystals diffract to 2.0 Å and a 94.2% complete data set to 2.2 Å has been collected from a single crystal with an R merge of 5.8%.
Structure and characterization of a novel chicken biotin-binding protein A (BBP-A)
2007
Background. The chicken genome contains a BBP-A gene showing similar characteristics to avidin family genes. In a previous study we reported that the BBP-A gene may encode a biotin-binding protein due to the high sequence similarity with chicken avidin, especially at regions encoding residues known to be located at the ligand-binding site of avidin. Results. Here, we expand the repertoire of known macromolecular biotin binders by reporting a novel biotin-binding protein A (BBP-A) from chicken. The BBP-A recombinant protein was expressed using two different expression systems and purified with affinity chromatography, biochemically characterized and two X-ray structures were solved – in comp…
Uranyl sorption onto birnessite: A surface complexation modeling and EXAFS study
2014
This work investigates the mechanism of the uranyl interaction with birnessite, one of the most common layer-type MnO2 mineral at the Earth's surface, by coupling macroscopic (surface complexation experiments) and microscopic (EXAFS measurements) approaches. The sorption of uranyl on synthetic hexagonal birnessite, the low-pH birnessite form, was studied under various conditions of pH (3–6), electrolyte backgrounds (0.1 M NaClO4, NaNO3 and Na2CO3), and solid/liquid ratios (from 0.27 to 4.5 g/L). Sorption isotherms exhibit a complex form indicative of at least two types of sorption sites. EXAFS data reveal the presence of two equatorial O shells at ca. 2.32 Å and 2.46 Å for all the samples, …
Synthesis, Structure and Antimicrobial Activity of New Co(II) Complex with bis-Morpholino/Benzoimidazole-s-Triazine Ligand
2023
A new Co(II) perchlorate complex of the bis-morpholino/benzoimidazole-s-triazine ligand, 4,4′-(6-(1H-benzo[d]imidazol-1-yl)-1,3,5-triazine-2,4-diyl)dimorpholine (BMBIT), was synthesized and characterized. The structure of the new Co(II) complex was approved to be [Co(BMBIT)2(H2O)4](ClO4)2*H2O using single-crystal X-ray diffraction. The Co(II) complex was found crystallized in the monoclinic crystal system and P21/c space group. The unit cell parameters are a = 22.21971(11) Å, b = 8.86743(4) Å, c = 24.38673(12) Å and β = 113.4401(6)°. This heteroleptic complex has distorted octahedral coordination geometry with two monodenatate BMBIT ligand units via the benzoimidazole N-atom and four water …
Aqueous foam as the carrier phase in the deposition of fibre networks
2015
Microspectroscopy and spectromicroscopy with photoemission electron microscopy using a new kind of imaging energy filter
2001
The use of an imaging retarding field analyser attached to the FOCUS IS-PEEM is described. This kind of energy filter is a simple, powerful tool to obtain microspectra from areas of down to about 1 μm using (V)UV and X-ray excitation sources. First results of microspectroscopy measured by excitation with a laboratory as well as a synchrotron X-ray source are presented.
Deep ROSAT-HRI observation of the cD galaxy NGC 1399 in the fornax cluster: Morphology and dynamical status of the X-ray halo
2002
We present the results of a deep (167 ks) observation of the NGC 1399/NGC 1404 field obtained from data collected between 1993 and 1996 with the ROSAT High Resolution Imager. We take advantage of the 5" resolution of the HRI to study in detail the structure of the galactic halo and to relate the results to those obtained at larger scales with poorer resolution instruments. We discuss possible non-equilibrium scenarios that may explain the global halo structure. We also find evidence of interactions between the nuclear radio source and the inner gaseous halo.
The Structural Diversity of Benzofuran Resorcinarene Leads to Enhanced Fluorescence
2014
An unexpected and previously unknown resorcinarene mono-crown with a fused benzofuran moiety in its macrocyclic core was obtained as a byproduct from a bridging reaction of tetramethoxy resorcinarene with tetraethylene glycol ditosylate. The formation of the fused benzofuran moiety in the resorcinarene macrocycle resulted in a unique rigid and puckered boat conformation, as shown by XRD studies in the solid state. Modification of the macrocycle was also observed to affect the photophysical properties in solution by enhancing the fluorescence brightness compared with a conventional resorcinarene macrocycle. The fluorescent properties enabled unique detection of structural features, that is, …
Observatory science with eXTP
2019
Disponible preprint en: arXiv:1812.04023v1 [astro-ph.HE] [v1] Mon, 10 Dec 2018 19:00:52 UTC (4,376 KB)
Solid-state compatibility of Ca:LaNbO4 with perovskite cathodes: Evidences from X-ray microspectroscopy
2022
The solid-state compatibility between calcium-doped lanthanum niobate and three perovskite cathode materials was investigated using two X-ray microbeam techniques, micro X-ray fluorescence and micro X-ray absorption spectroscopy. The cathode powders (lanthanum strontium ferrite, either cobalt or copper-doped, and lanthanum strontium cobaltite) in contact with the dense electrolyte pellet were annealed at 1150 degrees C for 12-144 h to simulate the effect of thermal stresses due to fabrication and long-term operation. As a result, several interdiffusion phenomena were then observed on the bilayer cross-sections: in particular, the chemical state and coordination environment of calcium, iron,…