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21.
Structural phases of ordered FePc-nanochains self-assembled on Au(110)
Betti Maria Grazia, Pierluigi Gargiani, Carlo Mariani, Roberto Biagi, Jun Fujii, Giorgio Rossi, Andrea Resta, Stefano Fabris, Sara Fortuna, Xavier Torrelles, Manvendra Kumar, Maddalena Pedio, 2012, original scientific article

Abstract: Iron-phthalocyanine molecules deposited on the Au(110) reconstructed channels assemble into one-dimensional molecular chains, whose spatial distribution evolves into different structural phases at increasing molecular density. The plasticity of the Au channels first induces an ordered phase with a 5×5 symmetry, followed by a second long-range ordered structure composed by denser chains with a 5×7 periodicity with respect to the bare Au surface, as observed in the low-energy electron-diffraction (LEED) and grazing incidence X-ray diffraction (GIXRD) patterns. The geometry of the FePc molecular assemblies in the Au nanorails is determined by scanning tunneling microscopy (STM). For the 5×7 phases, the GIXRD analysis identifies a “4-3” rows profile along the [001] direction in the Au surface and an on-top FePc adsorption site, further confirmed by density functional theory (DFT) calculations. The latter also reveals the electronic mixing of the interface states. The chain assembly is driven by the molecule–molecule interaction and the chains interact with the Au nanorails via the central metal atom, while the chain–chain distance in the different structural phases is primarily driven by the plasticity of the Au surface.
Found in: ključnih besedah
Summary of found: ...adsorption site, further confirmed by density functional theory (DFT) calculations. The latter also reveals the...
Keywords: STM, LEED, DFT, density functional theory, phthalocyanine, Au(110), gold, surface
Published: 13.10.2016; Views: 3184; Downloads: 0
.pdf Fulltext (1,33 MB)

22.
Spin and orbital configuration of metal phthalocyanine chains assembled on the Au(110) surface
Gargiani Pierluigi, Giorgio Rossi, Roberto Biagi, Valdis Corradini, Maddalena Pedio, Sara Fortuna, Arrigo Calzolari, Stefano Fabris, Julio Criginski Cezar, N. B. Brookes, Maria Grazia Betti, 2013, original scientific article

Abstract: The spin and orbital configuration of magnetic metal phthalocyanines (MPcs) deposited on metallic substrates are strongly influenced by the rehybridization of the molecular states with the underlying metal. FePc, CoPc, and CuPc isolated molecules are archetypal systems to investigate the interrelationship between magnetic moments and orbital symmetry after deposition on a metallic substrate. MPcs form long-range ordered chains self-assembled along the reconstructed channels of the Au(110) surface. X-ray magnetic circular dichroism from the L2,3 absorption edges of Fe, Co, and Cu shows that the orbital and spin configuration are strongly modified upon adsorption on the Au(110) surface if the orbitals responsible of the magnetic moment are involved in the interaction process. The magnetic moment for a single layer of molecular chains is completely quenched for the CoPc molecules, fully preserved for the CuPc and reduced for the FePc ones. The modified magnetic configuration is confined to the very interface layer, i.e., to the MPc molecules bound to the metal substrate up to the compact packing of the single layer. The different response can be rationalized in terms of the symmetry/orientation of the metal-ion d states interacting with the substrate states, as indicated by density functional theory calculations in agreement with experimental findings.
Found in: ključnih besedah
Summary of found: ...substrate states, as indicated by density functional theory calculations in agreement with experimental findings....
Keywords: phthalocyanine, Au(110), gold, self-assembly, pattern, configuration, density functional theory, DFT, CuPc, FePc
Published: 12.10.2016; Views: 3026; Downloads: 0
.pdf Fulltext (1,73 MB)

23.
Phase behaviour of self-assembled monolayers controlled by tuning physisorbed and chemisorbed states: a lattice-model view
Sara Fortuna, David L. Cheung, Karen Johnston, 2016, original scientific article

Abstract: The self-assembly of molecules on surfaces into 2D structures is important for the bottom-up fabrication of functional nanomaterials, and the self-assembledstructure depends on the interplay between molecule-molecule interactions and molecule-surface interactions. Halogenated benzene derivatives on platinum have been shown to have two distinct adsorption states: a physisorbed state and a chemisorbed state, and the interplay between the two can be expected to have a profound effect on the self-assembly and phase behaviour of these systems. We developed a lattice model that explicitly includes both adsorption states, with representative interactions parameterised using density functional theory calculations. This model was used in Monte Carlo simulations to investigate pattern formation of hexahalogenated benzene molecules on the platinumsurface. Molecules that prefer the physisorbed state were found to self-assemble with ease, depending on the interactions between physisorbed molecules. In contrast, molecules that preferentially chemisorb tend to get arrested in disordered phases. However, changing the interactions between chemisorbed and physisorbed molecules affects the phase behaviour. We propose functionalising molecules in order to tune their adsorption states, as an innovative way to control monolayer structure, leading to a promising avenue for directed assembly of novel 2D structures.
Found in: ključnih besedah
Summary of found: ...with representative interactions parameterised using density functional theory calculations. This model was used in Monte...
Keywords: lattice model, hexagonal lattice, Monte Carlo, DFT, density functional theory, benzene, physisorption, chemisorption, halogenated
Published: 11.10.2016; Views: 2977; Downloads: 0
.pdf Fulltext (5,75 MB)

24.
Oxalic acid adsorption states on the clean Cu(110) surface
Sara Fortuna, 2016, original scientific article

Abstract: Carboxylic acids are known to assume a variety of configurations on metallic surfaces. In particular oxalic acid on the Cu(110) surface has been proposed to assume a number of upright configurations. Here we explore with DFT calculations the possible structures that oxalic acid can form on copper 110 at different protonation states, with particular attention at the possibility of forming structures composed of vertically standing molecules. In its fully protonated form it is capable of anchoring itself on the surface thanks to one of its hydrogen-free oxygens. We show the monodeprotonated upright molecule with two oxygens anchoring it on the surface to be the lowest energy conformation of a single oxalic molecules on the Cu(110) surface. We further show that it is possible for this configuration to form dense hexagonally arranged patterns in the unlikely scenario in which adatoms are not involved.
Found in: ključnih besedah
Summary of found: ...oxalate, cu(110), copper, surface, adsorption, density functional theory, DFT...
Keywords: oxalic acid, oxalate, cu(110), copper, surface, adsorption, density functional theory, DFT
Published: 11.10.2016; Views: 2807; Downloads: 0
.pdf Fulltext (1,21 MB)

25.
Thermal Lens Spectrometry and Microscopy Analytical Chemist’s Approach
Mladen Franko, unpublished invited conference lecture

Abstract: This lecture introduces the basic concepts and recent progres in theory, instrumentation and applications of thermal lens spectrometry, thermal lens microscopy and their utilization for highly sensitive, and high throughput detection in liquid chromatography, flow injectionanalysis in microfluidic systems.
Found in: ključnih besedah
Summary of found: ...the basic concepts and recent progres in theory, instrumentation and applications of thermal lens spectrometry,...
Keywords: Thermal lens spectrometry, TLS microscopy, theory, applications
Published: 01.03.2017; Views: 3139; Downloads: 1
.pdf Fulltext (17,07 MB)
This document has many files! More...

26.
Characterization of Mg low-index surfaces by first-principles
Miha Gunde, 2017, master's thesis

Abstract: In this work, three surfaces, namely, Mg(0001), Mg(10 ̄1 0) and Mg(11 ̄2 0) are investigated by means of Density Functional Theory and Generalized Gradient Approximation first-principle calculations. The surfaces have been characterized in terms of their interlayer distances, surface energies, Projected Density of States and Surface Core Level Shifts. Contrary to what was found in previous studies based on Density Functional Theory-Local Density Approximation, the use of Generalized Gradient Approximation exchange correlation functional unravels the oscillatory behavior of both interlayer distances and Surface Core Level Shifts of Mg(10 ̄1 0). Moreover, the Projected Density Of States of un-reconstructed Mg(11 ̄2 0) exhibit the typical quantisation of electronic levels associated to a 2D-confinement of a 3D nearly-free electron gas, as observed in nano-wires, and a Peierls instability along the unconfined direction. Different possible reconstructions on Mg(11 ̄2 0) have then been investigated. In particular, it is found that the surface energy of (2X1) and (3X1) reconstructions is almost degenerate and lower than the surface energy of the unreconstructed Mg(11 ̄2 0) surface. Because of the quasi-degeneracy of surface energies, Mg(11 ̄2 0) surface should be composed by a combination of all the quasi degenerate phases.
Found in: ključnih besedah
Summary of found: ...are investigated by means of Density Functional Theory and Generalized Gradient Approximation first-principle calculations. The...
Keywords: Density Functional Theory, first-principle calculations, Mg surface, Surface Core-Level Shift, surface relaxation, surface reconstruction
Published: 04.07.2017; Views: 4145; Downloads: 2015
.pdf Fulltext (1,77 MB)

27.
Un approccio graph-theoretic alla progettazione di basi di dati XML guidato dal tipo e dalla frequenza delle interrogazioni.
Federico Torzo, 2015, undergraduate thesis

Found in: ključnih besedah
Keywords: databases design, XML schema, algorithms, graph theory
Published: 12.07.2017; Views: 2441; Downloads: 0
.pdf Fulltext (3,63 MB)

28.
Heart rate variability and nonlinear dynamic analysis in patients with stress-induced cardiomyopathy
Antonija Krstačić, Paolo Castiglioni, Dragan Gamberger, Gianfranco Parati, Goran Krstačić, Robert Steiner, 2012, original scientific article

Abstract: Complexity-based analyses may quantify abnormalities in heart rate variability (HRV). The aim of this study was to investigate the clinical and prognostic significances of dynamic HRV changes in patients with stress-induced cardiomyopathy Takotsubo syndrome (TS) by means of linear and nonlinear analysis. Patients with TS were included in study after complete noninvasive and invasive cardiovascular diagnostic evaluation and compared to an age and gender matched control group of healthy subjects. Series of R–R interval and of ST–T interval values were obtained from 24-h ECG recordings after digital sampling. HRV analysis was performed by ‘range rescaled analysis’ to determine the Hurst exponent, by detrended fluctuation analysis to quantify fractal longrange correlation properties, and by approximate entropy to assess time-series predictability. Short- and long-term fractal-scaling exponents were significantly higher in patients with TS in acute phases, opposite to lower approximate entropy and Hurst exponent, but all variables normalized in a few weeks. Dynamic HRV analysis allows assessing changes in complexity features of HRV in TS patients during the acute stage, and to monitor recovery after treatment, thus complementing traditional ECG and clinically analysis.
Found in: ključnih besedah
Summary of found: ...Heart rate variability, Nonlinear dynamics, Chaos theory, Stress-induced cardiomyopathy, Takotsubo syndrome...
Keywords: Heart rate variability, Nonlinear dynamics, Chaos theory, Stress-induced cardiomyopathy, Takotsubo syndrome
Published: 13.07.2017; Views: 2835; Downloads: 0
.pdf Fulltext (742,92 KB)

29.
Sets of Invariant Measures and Cesaro Stability
Sergey Kryzhevich, 2017, original scientific article

Abstract: We take a space X of dynamical systems that could be: homeomorphisms or continuous maps of a compact metric space K or diffeomorphisms of a smooth manifold or actions of an amenable group. We demonstrate that a typical dynamical system of X is a continuity point for the set of probability invariant measures considered as a function of a map, let Y be the set of all such continuity points. As a corollary we prove that for typical dynamical systems average values of continuous functions calculated along trajectories do not drastically change if the system is perturbed.
Found in: ključnih besedah
Summary of found: ...ergodic theory, invariant measures, shadowing, stability, tolerance stability, topological...
Keywords: ergodic theory, invariant measures, shadowing, stability, tolerance stability, topological dynamics
Published: 02.10.2017; Views: 2192; Downloads: 0
.pdf Fulltext (529,51 KB)

30.
There is Faith and Faith: prosodic contrast in Serbo-Croatian and Slovenian verb derivation
Marko Simonović, 2018, published scientific conference contribution abstract

Found in: ključnih besedah
Summary of found: ...Verbs, Prosody, Optimality Theory, Distributed Morphology, Faithfulness, Theme vowels, Serbo-Croatian, Slovenian...
Keywords: Verbs, Prosody, Optimality Theory, Distributed Morphology, Faithfulness, Theme vowels, Serbo-Croatian, Slovenian
Published: 12.06.2018; Views: 2321; Downloads: 172
.pdf Fulltext (28,54 KB)

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