Search results for " diffraction"

showing 6 items of 896 documents

Entrapment of a linear water pentamer into a uranyl-salophen dimer in the solid state

2019

In the solid state, uranyl-salophen complex 1, decorated with bipyridyl sidearms, self-assembles from moist acetonitrile into dimeric species displaying a confined water pentamer, as observed by X-...

self-assembly; single crystal X-ray diffraction; uranyl-salophen complexes; Water clusters010405 organic chemistryPentamerDimerSolid-stateGeneral Chemistryself-assembly010402 general chemistry01 natural sciences0104 chemical sciencesEntrapmentchemistry.chemical_compoundWater clusterschemistryUranyl salophenPolymer chemistrySelf-assemblyuranyl-salophen complexesConfined waterAcetonitrilesingle crystal X-ray diffraction
researchProduct

A fluorescence study of the loading and time stability of doxorubicin in sodium cholate/PEO-PPO-PEO triblock copolymer mixed micelles

2019

Abstract Hypothesis Doxorubicin hydrochloride (DX) is one of the most powerful anticancer agents though its clinical use is impaired by severe undesired side effects. DX encapsulation in nanocarrier systems has been introduced as a mean to reduce its toxicity. Micelles of the nonionic triblock copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) (PEO-PPO-PEO), are very promising carrier systems. The positive charge of DX confines the drug to the hydrophilic corona region of the micelles. The use of mixed micelles of PEO-PPO-PEO copolymers and a negatively charged bile salt should favour the solubilization of DX in the apolar core region of the micelles. Experiments We st…

small angle X-raymacromolecular substances02 engineering and technology010402 general chemistry01 natural sciencesMicelledoxorubicinFluorescence spectroscopyfluorescence; doxorubicin; pluronics bile salts; dynamic light scattering; small angle X-ray; scattering drug-deliveryPolyethylene GlycolsBiomaterialsColloid and Surface ChemistryDynamic light scatteringX-Ray DiffractionScattering Small AngleCopolymerMicellesDrug CarriersAqueous solutionAntibiotics AntineoplasticSmall-angle X-ray scatteringChemistrytechnology industry and agricultureWaterdynamic light scatteringPoloxamer021001 nanoscience & nanotechnologySodium Cholate0104 chemical sciencesSurfaces Coatings and FilmsElectronic Optical and Magnetic Materialspluronics bile saltsSpectrometry FluorescenceChemical engineeringSolubilityPropylene Glycolsscattering drug-deliveryfluorescenceNanocarriers0210 nano-technology
researchProduct

CO(2)-water supercritical mixtures: Test of a potential model against neutron diffraction data

2007

Abstract A neutron diffraction experiment on supercritical mixtures of water and CO 2 at two concentrations is presented. Data are analyzed within the EPSR framework and the water–water and water–CO 2 radial distribution functions are compared with those calculated by a Molecular Dynamics simulation performed by using the TIPS2 and EPM-M potential models for water and CO 2 respectively. It is found that the Molecular Dynamics simulation reproduces the overall shape of the site–site radial distribution functions, although missing a few subtle changes brought along when the CO 2 concentration is increased.

supercritical fluidChemistryNeutron diffractionAnalytical chemistryThermodynamicsRadial distributionCondensed Matter PhysicsAtomic and Molecular Physics and OpticsSupercritical fluidElectronic Optical and Magnetic MaterialsMolecular dynamicsneutron diffractionMaterials ChemistryAstrophysics::Earth and Planetary AstrophysicsPhysical and Theoretical ChemistryPhysics::Atmospheric and Oceanic PhysicsSpectroscopy
researchProduct

Progress in HAXPES performance combining full-field k-imaging with time-of-flight recording

2019

Journal of synchrotron radiation 26(6), 1996-2012 (2019). doi:10.1107/S1600577519012773

time-of-flight microscopeDiffractionNuclear and High Energy PhysicsMaterials scienceMicroscopePhoton550530 Physics02 engineering and technologyKinetic energy01 natural scienceslaw.inventionOpticslaw0103 physical sciencesddc:550HAXPES010306 general physicsInstrumentationMonochromatorRadiationk-spacebusiness.industry021001 nanoscience & nanotechnology530 PhysikResearch PapersBrillouin zoneWavelengthTime of flightBrillouin zone0210 nano-technologybusinessX-ray photoelectron diffraction
researchProduct

Observation of the Early Structural Changes Leading to the Formation of Protein Superstructures.

2014

Formation of superstructures in protein aggregation processes has been indicated as a general pathway for several proteins, possibly playing a role in human pathologies. There is a severe lack of knowledge on the origin of such species in terms of both mechanisms of formation and structural features. We use equine lysozyme as a model protein, and by combining spectroscopic techniques and microscopy with X-ray fiber diffraction and ab initio modeling of Small Angle X-ray Scattering data, we isolate the partially unfolded state from which one of these superstructures (i.e., particulate) originates. We reveal the low-resolution structure of the unfolded state and its mechanism of formation, hi…

unfolded stateChemistryMechanism (biology)Ab initioModel proteinamyloid superstructure SAXS Spectroscopy Fluorescence microscopy dye diffusionNanotechnologyProtein aggregationBiophysicsGeneral Materials ScienceLack of knowledgePhysical and Theoretical Chemistryconformational changesFiber diffractionparticulateprotein superstructureshydrophobicity
researchProduct

Composition and corrosion phases of Etruscan Bronzes from Villanovan Age

2008

A neutron diffraction (ND) and neutron tomography (NT) study of laminated ancient bronzes was performed at the ISIS (Rutherford Appleton Laboratory, UK) neutron source and at the BENSC reactor (Hahn-Meitner Institut, Germany). The samples are part of an 8th century BC Etruscan collection discovered in the necropolises of Osteria-Poggio Mengarelli and Cavalupo in the Vulci area (Viterbo, Italy). The study allowed us to derive-in a totally non-destructive manner-information related to the main composition of the objects, possible presence of alterations and their nature, crusts and inclusions, as well as structure of the bulk. The presence of some components is linked to a variety of question…

working methodAncient bronzes; Chemical environment; Corrosion; Neutron diffraction; Neutron tomography; Structure of the bulk; Working methodsancient bronzebusiness.industryApplied MathematicsMetallurgyNeutron diffractionNeutron tomographySettore FIS/01 - Fisica SperimentaleChemical environmentSettore FIS/07 - Fisica Applicata(Beni Culturali Ambientali Biol.e Medicin)Neutron diffractionCorrosionAncient bronzesCorrosionNeutron tomographyOpticsNeutron sourceWorking methodsneutron diffraction neutron tomography ancient bronzes corrosion chemical environment working methods structure of the bulkStructure of the bulkbusinessInstrumentationEngineering (miscellaneous)Geology
researchProduct