1,721,609 research outputs found
3. F. Cavazzana Romanelli, G. Grivaud, Cyprus 1542. The Great Map of the Island by Leonida Attar, 2006
No full textFourrier Sabine. 3. F. Cavazzana Romanelli, G. Grivaud, Cyprus 1542. The Great Map of the Island by Leonida Attar, 2006. In: Cahiers du Centre d'Etudes Chypriotes. Volume 36, 2006. pp. 250-251
On the line-shape analysis of Compton profiles and its application to neutron scattering
No full textAnalytical properties of Compton profiles are used in order to simplify the analysis of neutron Compton scattering experiments. In particular, the possibility to fit the difference of Compton profiles is discussed as a way to greatly decrease the level of complexity of the data treatment, making the analysis easier, faster and more robust. In the context of the novel method proposed, two mathematical models describing the shapes of differenced Compton profiles are discussed: the simple Gaussian approximation for harmonic and isotropic local potential, and an analytical Gauss-Hermite expansion for an anharmonic or anisotropic potential. The method is applied to data collected by VESUVIO spectrometer at ISIS neutron and muon pulsed source (UK) on Copper and Aluminium samples at ambient and low temperatures
An effective hydrogen scattering cross section for time-of-flight neutron experiments with simple organic molecules
No full textThe wavelength dependence of the effective neutron cross section for hydrogen has been investigated by measuring the transmitted total scattering cross section in urea, beta -alanine, tartaric acid and polyethylene over the energy range 3meV to 10eV. Under the assumption that carbon, nitrogen and oxygen atoms contribute a small and invariant amount to the measured total cross section, these data represent a direct measure of the wavelength dependence of the overall scattering contribution of the hydrogen atoms to the total cross section. These experimental data can be used to apply effective wavelength-dependent corrections to neutron scattering data of hydrogen-rich simple organic compounds
Early cardiovascular involvement in chronic obstructive pulmonary disease.
No full textCardiovascular (CV) disease represents a considerable risk factor in terms of both morbidity and mortality in elderly patients with chronic obstructive pulmonary disease (COPD). In fact, there is a considerable evidence of this association: for only 20 years forced expiratory volume in 1 second (FEV1) has been considered as predictive of cardiovascular mortality especially in elderly patients. At present, the emerging evidence suggests that hypoxia, systemic inflammation, oxidative stress may cause an early sub-clinical cardiovascular involvement in patients with COPD. Aging is a selective process dramatically affecting certain portions of the cardiovascular system for example: diminished beta-adrenergic responsiveness, increased myocardial and vascular stiffness, decreased arterial baroreflex, vagal outflow and compromission of diastolic function. The nature of these interactions is complex and involves not only mechanisms of aging but also multiple defined and undefined (e.g., genetic) risk factors. Cardiovascular diseases are the main causes of mortality among the subjects with impaired lung function. Even mild reductions in expiratory flow volumes amplify the risk of ischemic heart diseases, strokes, and sudden cardiac deaths 2- to 3-fold, independent of other risk factors. The mechanism or mechanisms responsible for this association, however, remain largely unknown
Exploring the Pion Phenomenology Within a Fully Covariant Constituent Quark Model
No full textAn overview of the vector and tensor Generalized Parton Distributions for a charged pion is presented. Such observables, belonging to the set of quantities fundamental for a detailed investigation of the hadronic inner dynamics, have been evaluated within a fully covariant Constituent Quark Model, based on a proper Ansatz of the pion Bethe–Salpeter Amplitude and the Mandelstam formula for matrix elements of operators acting on relativistic composite systems. Given the very encouraging results already obtained for the vector distribution of a charged pion, the model has been extended to the tensor one, and some preliminary calculations will be illustrated
Determination of effective temperatures of hydrogenated and deuterated alcohols using the VESUVIO spectrometer
No full textWe studied the effective temperatures of hydrogen and deuterium in normal 1-propanol, 2-propanol and n-butanol and fully deuterated 2-propanol and n-butanol at the VESUVIO spectrometer (ISIS Pulsed Neutron and Muon Source, Rutherford Appleton Laboratory, UK). We found that the effective temperature of H (D) is about 3.9 (2.9) times higher than room temperature, where the experiments were performed. The results from the present analysis were compared to the results from the standard data treatment available in the MANTID software for DINS data, and to results from Molecular Dynamics simulations. We find that the final results obtained following these independent routes agree within few points per cent. We also provide a detailed discussion on how to handle experimental backgrounds, the need to analyze groups of detectors to increase the signal-to-background ratio, and we suggest a range of scattering angles for which the analysis is more robust.Fil: Dawidowski, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Rodriguez Palomino, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Romanelli, G.. ISIS Neutron and Muon Source. Rutherford Appleton Laboratory; Reino UnidoFil: Cuello, Gabriel Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Institut Laue Langevin; FranciaFil: Marquez Damian, Jose Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Robledo, José Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Krzystyniak, Matthew Iej. ISIS Neutron and Muon Source. Rutherford Appleton Laboratory; Reino Unid
Kinetic energy and radial momentum distribution of hydrogen and oxygen atoms of water confined in silica hydrogel in the temperature interval 170–325 K
No full textWater is an ubiquitous liquid and it is necessary for life;. Studies on water are therefore of obvious scientific and ....
technological relevance. In view of its peculiar physicalproperties (the so-called water anomalies, particularly relevant
at low temperatures [1]), studies on water structureand dynamics in ample temperature intervals, covering also
the supercooling region, have attracted much interest in recent years. In particular, studies focused on the supercooled
phase are important in order to test theories and hypotheses[2,3], including the liquid-liquid phase transition hypothesis
[4-6] and the related fragile-to-strong crossover observed inwater confined in silica matrices and in the hydration water
of proteins [7,8]. In this context, water confined withinnanometer-sized porous hydrophilic/hydrophobic matrices
has been investigated both to extend the supercooling temperaturerange accessible to experiment and to mimic the
crowding/confined conditions experienced by water moleculesin biological systems relevant to biophysics, bio-preservation,and pharmaceutics. In view of the abovearguments, studies on the short-time dynamics of hydrogen
and oxygen atoms of supercooled water (bulk or confined) are of great relevance
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