Dipartimento di Fisica - Tesi di Dottorato

Permanent URI for this collectionhttp://localhost:4000/handle/10955/35

Questa collezione raccoglie le Tesi di Dottorato afferenti al Dipartimento di Fisica dell'Università della Calabria.

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Start date: 2010End date: 2019

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Now showing 1 - 10 of 156
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    Towards more sustainable organic processes : heterocyclizations in non-conventional solvents
    (2017-09-19) Maner, Asif S.; Carbone, Vincenzo; Gabriele, Bartolo; Mancuso, Raffaella
    This thesis reports the synthesis of important heterocyclic derivatives by iodocyclization, carbonylation and cycloisomerization reactions in Non-Conventionl solvents like deep eutectic solvents (DES) and Ionic Liquids (ILs). In chapter one general aspects of green and sustainable chemistry and introduction to eco-friendly green solvents such as water, DES, ScCO2 and ILs are described. Carbonylation processes, their advantages, types were described along with the application of transition metal catalysis in the carbonylation reactions with mechanistic approaches discussed. In chapter two, we describe a convenient and general method for the synthesis of substituted thiophenes through heterocyclodehydration and iodocyclization of readily available 1-mercapto-3-alkyn-2-ols in DES as the solvents. In chapter three we discuss a convenient carbonylative approach to 2-oxazolidinone derivatives carried out in an ionic liquid as the solvent (EmimEtSO4) is presented. It is based on the sequential concatenation of two catalytic cycles, both catalyzed by the same metal species (auto-tandem catalysis). In chapter four we present iodocyclization reactions to obtain iodinated isobenzofuranones and isochromenones by iodolactonization of 2-alkynyl benzoic acids in ionic liquids. In particular here we have developed divergent syntheses of (E)-3-(iodoalkylidene) isobenzofuran-1(3H)-ones and 4-iodo-1H-isochromen-1-ones by base-free Iodolactonization of 2-alkynylbenzoic acids in ionic liquids. In chapter five we report the cycloisomerization of readily available 2-alkynylbenzoic acids using an ionic liquid as the reaction medium in the presence of CuCl2 as a simple and inexpensive catalyst. Although in principle two different cyclization pathways can be followed, leading to either 5-exo-dig mode or 6-endo-dig mode, we have found that substrates bearing an aryl group on the triple bond or a terminal triple bond can be selectively converted into the isobenzofuranone derivatives, using N-ethyl-N-methylmorpholinium dicyanamide (Mor1,2N(CN)2) as the solvent. On the other hand, and in a complementary manner, substrates substituted with an alkyl or an alkenyl group on the triple bond selectively led to isochromenones when the reaction was carried out EmimEtSO4 and with excellent recyclability of the catalyst/ionic liquid system.
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    Improving oilfield performance enabling horizontal drilling techniques: developments and optimization of standard and special measures for a real case study
    (2017-11-13) Al Taie, Amer Abdulhakim; Carbone, Vincenzo; Romagnoli, Raffaele
    Drilling technique is a crucial issue to pay attention to. Drilling a horizontal well has a great interest to the oil and gas industry since nowadays it provides attractive means for improving both production rate and yet the recovery efficiency. The great improvements in drilling technology make it possible to drill horizontally no matter how complex are the trajectories and how deep it is suppose to reach. This study aims at presenting the optimal design aspects of a horizontal well. Design aspects include the selection of bit and casing sizes, detection of setting depths and drilling fluid density, casing, hydraulics, well profile, and construction of drill string simulator. When many vertical wells exist, an oil field named (Z14 field) should be designated to have a short radius horizontal well able to increasing the productivity and to promote the developing of the field itself. A single build profile with build rate 90 deg/100ft is constructed based on geological data. A drill string simulator composed of soft-string model and buckling tendency is constructed to predict torque and drag of string for six operating conditions. These conditions are pick-up, slack-off, sliding, pick-up with rotation, slack-off with rotation and drilling with rotation. Results of loads analysis showed that the suggested drill string can be used without exceeding torsional, tensile and buckling strengths. Analysis of single build profile showed that the torque and drag while drilling horizontal well could be minimized by drilling with low build rate, employing lighter pipe, and improving the lubricating capability with oil base mud (low friction forces). A finite element model was constructed to predict inclination tendency for multistabilizer rotary BHA in three dimensions, static condition. The bottom hole assembly was idealized with beam element capable of resisting axial forces, bending moments about the two principal axes, and twisting moments about its centroidal axis. Bit and stabilizer were treated as contact point and restricted from movement in all directions. Each element is loaded with gravity and normal contact forces. Model validation showed closer agreement between the model and Jiazhi's method (analytic) for slick, single, and two stabilizers BHA, compared to Akgun results. Predictions with finite element model showed that for building assembly, the weight on bit had small effect on bit side force especially in high angle wells. Also inclination tendency (building, dropping) would depend on position of the stabilizer, diameter of drillcollar behind the bit, and number of stabilizers.
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    Rischio sismico ambientale e degli edifici: analisi tecnica HVSR - Aspetti teorici e aspetti sperimentali
    (2017-07-17) Magarò, Floriana; Carbone, Vincenzo; Zinno, Raffaele
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    TiO2 nanotubes in nanotechnologies
    (2017-10-10) Jimenez, Leticia; Versace, Carlo
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    Synthesis and characterization of nanomaterials: graphene, silicene and carbon nano- onions
    (2017-10-20) Osman, Salih Mohamed; Critelli, Salvatore; Caputi, Lorenzo
    The electronic structure of the graphene/Ni(111) system was investigated by means of electron energy-loss spectroscopy (EELS). A single layer of graphene has been obtained on Ni(111) by dissociation of ethylene. Angle-resolved EEL spectra show a low energy plasmon dispersing up to about 2 eV, resulting from fluctuation of a charge density located around the Fermi energy, due to hybridization between Ni and graphene states. The dispersion is typical of a two-dimensional charge layer, and the calculated Fermi velocity is a factor of ~0.5 lower than in isolated graphene. The interface-π plasmon, related to interband transitions involving hybridized states at the K point of the hexagonal Brillouin zone, has been measured at different scattering geometries. The resulting dispersion curve exhibits a square root behavior, indicating also in this case a two-dimensional character of the interface charge density. As well, it has been shown that it is possible to use EELS in the reflection mode to measure the fine structure of the carbon K-edge in monolayer graphene on Ni(111), thus demonstrating that reflection EELS is a very sensitive tool, particularly useful in cases where the TEM-based ELNES cannot be applied. Clean Ag(111) surface and the two phases of silicene on Ag(111), mixed (4×4, √13×√13R19°, 2√3×2√3R30°) and 2√3×2√3R30, have been studied by XPS, LEED and EELS. EEL spectra of the Ag(111) surface covered by silicene in the (4×4, √13×√13R19°, 2√3×2√3R30°) mixed phase shows a well-defined plasmon peak whose center is located at about 1.75 eV. The 2√3×2√3R30° phase shows EEL spectra that exhibit a peak located at about 0.75 eV loss, which moves clearly towards higher energies with increasing momentum transfer. The typical parabolic dispersion relation obtained from such spectra confirms that the peak is due to a collective excitation which is evidently associated to the silicene layer. These plasmons associated to silicene have never been observed in the past. Our results show that the plasmonic properties of silicene on Ag(111) are strongly dependent on the geometrical arrangement of Si atoms with respect to the substrate. Carbonaceous nanomaterials have been obtained by underwater arc discharge between graphite electrodes. TEM images showed that the resulting particles suspended in water consist of CNOs with other carbonaceous materials such as CNTs and graphene. We observed for the first time the formation of a solid agglomerate on the cathode surface. Raman and TEM studies revealed that the agglomerate is made exclusively of CNOs. The defragmentation of such agglomerate allows to obtain CNOs free of other carbonaceous materials without the complex purification procedures needed for floating nanomaterials
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    High-energy resummation in semi-hard processes at the LHC
    (2017-06-30) Celiberto, Francesco Giovanni; Carbone, Vincenzo; Papa, Alessandro
    Semi-hard processes in the large center-of-mass energy limit offer us an exclusive chance to test the dynamics behind strong interactions in kinematical sectors so far unexplored, the high luminosity and the record energies of the LHC providing us with a richness of useful data. In the Regge limit, s jtj, fixed-order calculations in perturbative QCD based on collinear factorisation miss the effect of large energy logarithms, which are so large to compensate the small QCD coupling s and must therefore be accounted for to all perturbative orders. The BFKL approach represents the most powerful tool to perform the resummation to all orders of these large logarithms both in the LLA, which means inclusion of all terms proportional to ( s ln(s))n, and NLA, which means inclusion of all terms proportional to s( s ln(s))n. The inclusive hadroproduction of forward jets with high transverse momenta separated by a large rapidity gap at the LHC, the so-called Mueller–Navelet jets, has been one of the most studied reactions so far. Interesting observables associated to this process are the azimuthal correlation momenta, showing a very good agreement with experimental data at the LHC. However, new BFKL-sensitive observables should be considered in the context of the LHC physics program. With the aim the to further and deeply probe the dynamics of QCD in the Regge limit, we give phenomenological predictions for four distinct semi-hard process. On one hand, we continue the analysis of reactions with two objects identified in the final state (i) by addressing open problems in the Mueller– Navelet sector and (ii) by studying the inclusive dihadron production in the full NLA BKFL accuracy. Hadrons can be detected at the LHC at much smaller values of the transverse momentum than jets, allowing us to explore an additional kinematical range, complementary to the one studied typical of Mueller– Navelet jets. Furthermore, this process permits to constrain not only the parton distribution functions for the initial proton, but also the parton fragmentation functions describing the detected hadron in the final state. On the other hand, we show how inclusive multi-jet production processes allow us to define new, generalised and suitable BFKL observables, where transverse momenta and rapidities of the tagged jets, well separated in rapidity from each other, appear in new combinations. We give the first phenomenological predictions for the inclusive three-jet production, encoding the effects of higher-order BFKL corrections. Then, making use of the same formalism, we present the first complete BFKL analysis for the four-jet production.
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    High-energy resummation in semi-hard processes at the LHC
    (2017-06-30) Celiberto, Francesco Giovanni; Carbone, Vincenzo; Papa, Alessandro
    Semi-hard processes in the large center-of-mass energy limit offer us an exclusive chance to test the dynamics behind strong interactions in kinematical sectors so far unexplored, the high luminosity and the record energies of the LHC providing us with a richness of useful data. In the Regge limit, s jtj, fixed-order calculations in perturbative QCD based on collinear factorisation miss the effect of large energy logarithms, which are so large to compensate the small QCD coupling s and must therefore be accounted for to all perturbative orders. The BFKL approach represents the most powerful tool to perform the resummation to all orders of these large logarithms both in the LLA, which means inclusion of all terms proportional to ( s ln(s))n, and NLA, which means inclusion of all terms proportional to s( s ln(s))n. The inclusive hadroproduction of forward jets with high transverse momenta separated by a large rapidity gap at the LHC, the so-called Mueller–Navelet jets, has been one of the most studied reactions so far. Interesting observables associated to this process are the azimuthal correlation momenta, showing a very good agreement with experimental data at the LHC. However, new BFKL-sensitive observables should be considered in the context of the LHC physics program. With the aim the to further and deeply probe the dynamics of QCD in the Regge limit, we give phenomenological predictions for four distinct semi-hard process. On one hand, we continue the analysis of reactions with two objects identified in the final state (i) by addressing open problems in the Mueller– Navelet sector and (ii) by studying the inclusive dihadron production in the full NLA BKFL accuracy. Hadrons can be detected at the LHC at much smaller values of the transverse momentum than jets, allowing us to explore an additional kinematical range, complementary to the one studied typical of Mueller– Navelet jets. Furthermore, this process permits to constrain not only the parton distribution functions for the initial proton, but also the parton fragmentation functions describing the detected hadron in the final state. On the other hand, we show how inclusive multi-jet production processes allow us to define new, generalised and suitable BFKL observables, where transverse momenta and rapidities of the tagged jets, well separated in rapidity from each other, appear in new combinations. We give the first phenomenological predictions for the inclusive three-jet production, encoding the effects of higher-order BFKL corrections. Then, making use of the same formalism, we present the first complete BFKL analysis for the four-jet production.
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    High-energy resummation in semi-hard processes at the LHC
    (2017-06-30) Celiberto, Francesco Giovanni; Carbone, Vincenzo; Papa, Alessandro
    Semi-hard processes in the large center-of-mass energy limit offer us an exclusive chance to test the dynamics behind strong interactions in kinematical sectors so far unexplored, the high luminosity and the record energies of the LHC providing us with a richness of useful data. In the Regge limit, s jtj, fixed-order calculations in perturbative QCD based on collinear factorisation miss the effect of large energy logarithms, which are so large to compensate the small QCD coupling s and must therefore be accounted for to all perturbative orders. The BFKL approach represents the most powerful tool to perform the resummation to all orders of these large logarithms both in the LLA, which means inclusion of all terms proportional to ( s ln(s))n, and NLA, which means inclusion of all terms proportional to s( s ln(s))n. The inclusive hadroproduction of forward jets with high transverse momenta separated by a large rapidity gap at the LHC, the so-called Mueller–Navelet jets, has been one of the most studied reactions so far. Interesting observables associated to this process are the azimuthal correlation momenta, showing a very good agreement with experimental data at the LHC. However, new BFKL-sensitive observables should be considered in the context of the LHC physics program. With the aim the to further and deeply probe the dynamics of QCD in the Regge limit, we give phenomenological predictions for four distinct semi-hard process. On one hand, we continue the analysis of reactions with two objects identified in the final state (i) by addressing open problems in the Mueller– Navelet sector and (ii) by studying the inclusive dihadron production in the full NLA BKFL accuracy. Hadrons can be detected at the LHC at much smaller values of the transverse momentum than jets, allowing us to explore an additional kinematical range, complementary to the one studied typical of Mueller– Navelet jets. Furthermore, this process permits to constrain not only the parton distribution functions for the initial proton, but also the parton fragmentation functions describing the detected hadron in the final state. On the other hand, we show how inclusive multi-jet production processes allow us to define new, generalised and suitable BFKL observables, where transverse momenta and rapidities of the tagged jets, well separated in rapidity from each other, appear in new combinations. We give the first phenomenological predictions for the inclusive three-jet production, encoding the effects of higher-order BFKL corrections. Then, making use of the same formalism, we present the first complete BFKL analysis for the four-jet production.
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    Development of integrated membrane systems for the treatment of olive mill wastewater and valorization of highadded value bioproducts
    (2017-07-21) Bazzarelli, Fabio; Carbone, Vincenzo; Giorno, Lidietta; Piacentini, Emma
    Nowadays, it is well recognized that advanced clean technologies, able to work in mild conditions and with low energy input are necessary to face challenges in environment protection, ratio nal use of water, production of naturally derived stable bioactive compounds. Membrane technologies fulfill these requirements. Studies are necessary to tune materials and processes for specific applications. The treatment of wastewaters coming from olive oil production is among the critical issues in agro food industry. The present work promoted advances in the development of novel membrane systems for the treatment of olive mill wastewater (OM WW). Th e se waters represent a severe environmental problem due to their high organic load and phytotoxic and antibacterial phenolic compounds, which resist to biological degradation . Additionally, the large volume of OMWW produced in combination with the short discarding time, increases the importance for disposal of this waste. On the other hand, OMWW represents a significant source of polyphenols for health benefits , which can be revalorized and used for medical or agro alimentary purposes. They also represent novel environmentally friendly formulation for chemical m anufacturing. The development of new strategies for the disposal of these by products appears to be extremely useful from an environmental and economic point of view. An advantageous solution is to transform what until now was considered junk to be dispos ed of in resource to be exploited and from which to draw profi t, through the recovery of high added value natural products (bioproducts) and water. In this context, integrated membrane systems can permit the selective recovery of bioactive compounds, such as polyphenols as well as water recovering and purification Moreover, membrane technology is considered a powerful tool for the sustainable industrial development, being able to well respond to the goal of the process intensification strategy” in terms of reduction of the plant size, increase of the plant efficiency, reduction of energy consumption and environmental impact. Nevertheless, one drawback of m embrane filtration of OMWW is the membrane fouling that drastically reduces the process performance. Therefore, OMWW pretreatment upstream of membrane process is necessary to limit fouling phenomena and to increase filtration efficiency. In this thesis, a co mprehensive study from OMWW treatment to biophenols recovery and valorization and water purification by means of integrated membrane process was carried out. Initially, studies focused on the decrease the fouling phenomena. For this purpose, a novel strate gy for a suitable pretreatment of OMWW was identified that permitted to obtain the total removal of suspended solids, through the aggregation and flocculation of particles by maintaining the pH of OMWW at isoelectric point. Secondly, the research focused o n the assessment of the potentiality of OMWW treatment by microfiltration and ultrafiltration process at the laboratory scale. Different organic and inorganic membrane materials were investigated, evaluating the permeation flux and the performance in terms of TOC (Total organic carbon) and polyphenols rejection . Afterwards, processes for OMWW purification aimed at obtaining of biologically active fractions at high concentration as well as their encapsulation were developed. For this purpose pressure-driven membrane processes such as microfiltration (MF) and nanofiltration (NF) and a relatively new membrane operation such as osmotic distillation (OD) were developed on lab scale prototype to obtain and concentrate fractions; membrane emulsification (ME) was st udied for the encapsulation of concentrated fractions. For MF operation, the efficiency of an air back flushing cycle was evaluated to keep constant the permeate flux during the OMWW processing processing. The overall integrated membrane system produced an enriched fraction of polyphenols, as well as a water stream that can be reused for irrigation or membrane cleaning. The highly concentrated polyphenols produced by osmotic distillation, is used as functional ingredients for formulation of water in oil (W/O) emulsions by membrane emulsification. The pulsed back and forward ME has been selected as low shear encapsulation method because it is particularly attractive for the production highly concentrated microemulsions without causing coalescence. The best operative cond itions (transmembrane pressure, wall shear stress) to control particle size and size distribution and obtain high productivity (dispersed phase flux) have been investigated . Water in oil emulsions with a narrow size distribution and high encapsulation effi ciency were obtained. Furthermore, in the present work a n ovel procedure for encapsulation of olive polyphenols with high load into solid lipid particles using traditional method (rotor stator homogenizer) and membrane emulsification was studied. Finally, a productive scale plant of the integrated membrane system was developed and installed at olive mill. The plant included the pre filtration unit, microfiltration, nanofiltration and a further step represented by reverse osmosis. The reverse osmosis has bee n used at large scale instead of membrane distillation due to its higher technology readiness level. Overall, this productive scale plant system proved efficient for fully recovery of biophenols in the retentate stream as well as reclamation of purified wa ter.
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    Nano materials and innovative laser-based accelerators for cultural heritage
    (2017-07-12) Veltri, Simona; Pantano, Pietro; Bonanno, Assunta; Antici, Patrizio
    Università della Calabria, Dipartimento di Fisica