Search results for "scanning"
showing 10 items of 1808 documents
3D digitization of transparent objects by polalization techniques in IR & by triangulation in UV
2011
Two non-conventional methods for the 3D digitization of transparent objects via non-contact measurement are reported in this thesis. 3D digitization is a well acknowledged technique for opaque objects and various commercial solutions based on different measurement approaches are available in the market offering different types of resolution at different prices. Since these techniques require a diffused or lambertian surface, their application to transparent surfaces fails. Indeed, rays reflected by the transparent surface are perturbed by diverse inter-reflections induced by the refractive properties of the object. Therefore, in industrial applications like quality control, the transparent …
Preparation and structural analysis of Fe2+xTi1−x thin films in the C14 Laves phase stability range
2002
Abstract We report the epitaxial growth of single phase (0 0 1)-oriented thin films of Fe2+xTi1−x in the C14 Laves phase stability range using molecular beam epitaxy (MBE). The growth was studied by reflection high-energy electron diffraction (RHEED) and X-ray diffraction (XRD). The onset temperature for epitaxial growth and the temperature range for improved crystalline coherence were identified. From X-ray reflectometry analysis the rms roughness was estimated to 0.5 nm for typical film thicknesses of 22 nm. As revealed by scanning tunneling microscopy (STM), this roughness is discrete and due to step edges corresponding to the full c-axis length of Fe2Ti. The epitaxial growth implies an …
Accurate and precise lattice parameters by selected-area electron diffraction in the transmission electron microscope
2009
8 páginas, 6 figuras, 7 tablas.
Morphology and magnetoresistance of Co2Cr0.6Fe0.4Al-based tunnelling junctions
2009
Some ferromagnetic Heusler compounds are theoretically predicted to be half metallic materials, i.e. to be characterized by a huge spin polarization at the Fermi energy. We investigate the correlations between junction preparation conditions, morphology and transport properties of planar MgO/Co2Cr0.6Fe0.4Al/AlOx/Co/CoOx/Pt tunnelling junctions. Epitaxial Co2Cr0.6Fe0.4Al thin films were deposited by dc and rf magnetron sputtering on different buffer layers (Cr, Fe, MgO) on MgO(1 0 0) substrates. By RHEED, LEED and in situ STM investigations different surface morphologies were observed. Atomically flat surfaces with Co2Cr0.6Fe0.4Al unit cell sized steps (B2 structure) were obtained by rf sput…
Liposomes as nonspecific nanocarriers for 5-Fluorouracil in the presence of cyclodextrins
2021
Abstract 5-Fluorouracil (5-FU) is one of anticancer drugs with broad activity. Due to its severe side effects, recent studies concentrate on new ways of directed 5-FU delivery and its release in ill tissue. One of selective carriers could be cyclodextrins and liposomes. The combination of novel methods, leading to formation of inclusion complexes (IC) between host molecule of β-cyclodextrin (β-CD) or 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) and 5-FU guest and its subsequent encapsulation in dipalmitoylphosphatidylcholine (DPPC) liposomes is studied experimentally in the present work. Several methods are applied to proof the encapsulation of the analysed drug and its release over time at 37 …
Monolayer Structure of Arachidic Acid on Graphite
2010
The self-assembly of arachidic acid (C(19)H(39)COOH) at the liquid solid interface between 1-phenyloctane (C(6)H(5)(CH(2))(7)CH(3)) and highly oriented pyrolytic graphite (HOPG) is studied by scanning tunneling microscopy (STM) to identify the structure of the monomolecular film. We observe the formation of highly ordered domains with molecules oriented in three different orientations compatible with the symmetry of the HOPG substrate, a spontaneous enantiomeric separation of the pro-chiral molecules, and reveal structural details with submolecular resolution. To determine the surface unit cell with an intrinsic calibration to the substrate atomic structure, the intermolecular distance is p…
Chemiluminescence response of ß-glucan stimulated leukocytes isolated from different tissues and peritoneal cavity of Dicentrarchus labrax
2003
Abstract The respiratory burst of leukocytes isolated from sea bass ( Dicentrarchus labrax ) pronephros, peritoneal cavity (P.C.), spleen and blood, was measured by a chemiluminescence (CL) assay after stimulation with β-glucan. The CL response by P.C. and pronephros leukocytes was significantly higher than that expressed by a similar number of cells separated from spleen and blood. This probably reflects the observation that the proportion of macrophages and neutrophils was highest in the populations of leukocytes from peritoneal cavity and pronephros. Comparative observations showed a higher degree of yeast phagocytosis by leukocytes taken from peritoneal cavity than the pronephros. Moreo…
Brain Synchrony in Competition and Collaboration During Multiuser Neurofeedback-Based Gaming
2021
EEG hyperscanning during multiuser gaming offers opportunities to study brain characteristics of social interaction under various paradigms. In this study, we aimed to characterize neural signatures and phase-based functional connectivity patterns of gaming strategies during collaborative and competitive alpha neurofeedback games. Twenty pairs of participants with no close relationship took part in three sessions of collaborative or competitive multiuser neurofeedback (NF), with identical graphical user interface, using Relative Alpha (RA) power as a control signal. Collaborating dyads had to keep their RA within 5% of each other for the team to be awarded a point, while members of competit…
Vecchi e nuovi rilievi
2014
L'introduzione di nuove tecnologie per il rilievo e la rappresentazione dell'architettura ha profondamente modificato l'approccio allo studio dei manufatti. Il contributo propone una rassegna dei nuovi strumenti evidenziando le potenzialità e i fattori critici impliciti nel loro utilizzo.
Lamination of swampy-rivulets Rivularia haematites stromatolites in a temperate climate
2001
Abstract Swampy-rivulets Rivularia haematites (D.C.) Agardh stromatolites were collected from the same site on the Plateau de Langres (Chaugey, France) over a seven year period. Specimens were studied in thin sections, in culture media under varying conditions of temperature and illumination, and by scanning electron microscope (SEM) in order to investigate the processes of calcification and lamination. New SEM observations confirm the polycrystalline structure of the ‘lamellae’ reported by the authors and show that the crystals composing these lamellae are elongate and aligned in the same direction as the filaments linked by them. The lamellae were also isolated in transverse sections unde…