Tesi di Dottorato
Permanent URI for this communityTesi di Dottorato
Browse
62 results
Search Results
Item Dynamic Methods for Monitoring Structural Health: analytical and experimental aspects(Università della Calabria, 2018-11) Miceli, Angela; Zinno, Raffaele; Carbone, VincenzoItem Towards more sustainable organic processes : heterocyclizations in non-conventional solvents(2017-09-19) Maner, Asif S.; Carbone, Vincenzo; Gabriele, Bartolo; Mancuso, RaffaellaThis 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.Item 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, RaffaeleDrilling 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.Item Rischio sismico ambientale e degli edifici: analisi tecnica HVSR - Aspetti teorici e aspetti sperimentali(2017-07-17) Magarò, Floriana; Carbone, Vincenzo; Zinno, RaffaeleItem High-energy resummation in semi-hard processes at the LHC(2017-06-30) Celiberto, Francesco Giovanni; Carbone, Vincenzo; Papa, AlessandroSemi-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.Item High-energy resummation in semi-hard processes at the LHC(2017-06-30) Celiberto, Francesco Giovanni; Carbone, Vincenzo; Papa, AlessandroSemi-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.Item High-energy resummation in semi-hard processes at the LHC(2017-06-30) Celiberto, Francesco Giovanni; Carbone, Vincenzo; Papa, AlessandroSemi-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.Item 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, EmmaNowadays, 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.Item Measurements of top quark pair production differential cross sections in √ the all-hadronic decay chennel in pp collisions AT s=13 TEV using the atlas detector(2019-07-31) Scornajenghi, Matteo; Carbone, Vincenzo; Tassi, EnricoIn this thesis, the measurements of the differential cross sections of top quark pair production in proton - proton collisions at a center of mass energy of p s = 13 TeV are presented. Data are collected at the LHC by the ATLAS detector during the 2015 and 2016 data-taking periods, corresponding to an integrated luminosity of L = 36:1 fb1. The top quark pair events are selected in the fully hadronic decay channel, resolved regime. The measurements are presented for several kinematics spectra and for observables sensitive to Initial and Final State Radiation. The measured spectra are corrected for detector effects and are compared to several theoretical Monte Carlo simulations. The measured spectra provide stringent tests of perturbative QCD, gives a better understanding of the top quark pair production mechanism and can be used to tune the Monte Carlo simulations. In addition, the expected performance of the Inner Tracker and the High Granularity Timing Detector, which will be installed during the Phase II upgrade of the ATLAS detector, will be presented.Item Description of potentially ordered liquid phases through statistical thermodynamics tools. Molecular field and computer similation approache:comparing two techniques.(2019-06-14) D'Urso, Christian; Carbone, Vincenzo; Celebre, GiorgioIl campo di ricerca in cui il Progetto si colloca è quello dello studio termodinamico statistico di sistemi uidi complessi, potenzialmente ordinati. Esso ha preso spunto dalle precedenti ricerche svolte presso il laboratorio LX-NMR S.C.An. del Dipartimento di Chimica e Tecnologie Chimiche dell'Università della Calabria dove, da lungo tempo, ci si occupa di problematiche connesse ai Cristalli Liquidi, conducendo studi che potrebbero essere de niti di 'base', miranti cioè alla comprensione delle interessantissime proprietà molecolari di cui godono questi sistemi. La nalità del Progetto implica, come appena detto, uno studio della materia a livello molecolare. Spesso, sulla base dei dati sperimentali raccolti (ad esempio, mediante le competenze NMR del Laboratorio presso il quale ha avuto luogo lo svolgimento del presente Progetto di Dottorato) si rende necessaria una 'interpretazione' dei risultati sperimentali, allo scopo di fornire una chiave di lettura dei fenomeni che avvengono su scala molecolare, in modo da coniugare, possibilmente, aspetti microscopici e macroscopici (provando cioè a fornire una giusti cazione e 'razionalizzazione' microscopica dei comportamenti macroscopici della materia stessa). Gli approcci adottati nel perseguire tale scopo devono necessariamente far riferimento alla Termodinamica Statistica. Storicamente, presso il Gruppo di Ricerca del Laboratorio presso il quale è stato sviluppato Progetto di Dottorato, l'approccio utilizzato è stato di tipo Molecular Field (MF); tuttavia, nell'ultima decade, grazie alla collaborazione con altri gruppi di Ricerca (in particolare, in collaborazione col prof. Giorgio Cinacchi ) ci si è avvicinati allo studio delle problematiche riguardanti le fasi parzialmente ordinate anche per mezzo di simulazioni numeriche (tipicamente Monte Carlo, ma non solo. . . ). Pertanto, nell'ottica di valorizzare sinergicamente quelle che possono essere considerate due importanti chiavi di lettura dei fenomeni a livello molecolare (ai quali, come Chimico-Fisici, siamo interessati), si è pensato di coniugare sinergicamente i due approcci (MF e MC) cui si è appena accennato. Entrambe le metodologie presentano ovviamente pregi e difetti, spesso (fortunatamente. . . ) complementari. Ad esempio, il MF ha il pregio di partire, tipicamente, da una certa 'semplicità' descrittiva, che spesso si origina su basi intuitive (a volte, anche 'elementari'), al ne di cogliere quelle che sono le caratteristiche essenziali dei fenomeni che si stanno investigando. Di contro, come pecca, esso risulta spesso troppo 'a grana grossa'; alle volte anche troppo essenziale nelle linee, tanto da non permettere di cogliere pienamente i dettagli e/o gli aspetti peculiari cui si aspirerebbe. D'altro canto, l'approccio stesso può presentare un aspetto matematico impegnativo, a causa di calcoli di un certo rilievo che richiedono l'utilizzo di software opportuni (spesso originali e/o commerciali), sebbene non sia strettamente necessario disporre di una imponente potenza di calcolo. Nelle simulazioni numeriche, al contrario, l'obiettivo è quello di costruire, partendo dalla modellizzazione delle interazioni molecolari, una 'realtà molecolare virtuale', ovviamente anch'essa in uenzata dalla metodologia utilizzata (Monte Carlo, Molecular Dynamics, ecc. . . ) che getti luce su aspetti magari meno intuitivi del comportamento dei sistemi uidi studiati. Per sperare di ottenere dei dati a dabili e realistici, però, occorre mettere in gioco una quantità di particelle signi cativa che può essere anche imponente (a seconda del fenomeno che si sta investigando), con la possibile conseguente dilatazione dei tempi di calcolo, a volte tali da rendere inattuabili i calcoli stessi. In tale ottica, per cogliere il meglio di entrambe le metodologie, è necessario a nostro avviso, metterle a confronto. Ciò che ci siamo dunque proposti per lo svolgimento del lavoro di Dottorato è stato di provare entrambi gli approcci il più possibile 'in parallelo'. Questa prospettiva risultava alquanto 'intrigante' e ci siamo riproposti di applicarla a quell'Universo ancora nebuloso rappresentato delle a ascinanti fasi termotropiche nematiche biassiali (ma non solo. . . vide infra). L'esistenza di tale mesofase è ancora oggi oggetto di dibattito, in quanto la prova ultima ed inequivocabile dell'osservazione di tali fasi non è stata fornita al di là d'ogni ragionevole dubbio; infatti, negli anni, questa fase ha pienamente meritato l'appellativo di fase 'elusiva e sfuggente', tale da essere de nita da alcuni ricercatori del campo, come il 'Sacro Graal' dei Cristalli Liquidi. Facendo riferimento più in dettaglio al lavoro di Tesi, abbiamo pensato di organizzare il materiale con una Introduzione complessiva, in cui si focalizzano quelle che saranno le nalità del lavoro. Il Capitolo 1, invece, è dedicato ad un'impostazione teorica generale della materia trattata, che farà da supporto anche per i successivi capitoli (senza però dilungarci nell'ennesima e ridondante descrizione dettagliata delle fasi liquido-cristalline, che risulta essere praticamente ubiquitaria, al ne di non appesantire eccessivamente la lettura). Nel Capitolo 2, ci si occupa di una parte consistente dell'attività del Progetto (parte del quale è stato svolto presso l'Università Autonoma di Madrid sotto la supervisione del prof. Giorgio Cinacchi. In tale periodo ci si è dedicati prevalentemente all'apprendimento delle metodologie (con particolare attenzione ai metodi MC), non solo teoricamente. ma anche e soprattutto dal punto di vista pratico. In particolare, abbiamo studiato come le caratteristiche di simme tria delle singole particelle componenti il sistema studiato (dunque, l'appartenenza delle molecole a particolari point groups, quali il D2h, C2h, C2v, ecc. . . ) possano, in linea di principio, originare regioni ove i sistemi acquisiscano, ad es., la caratteristica di essere orientazionalmente biassiali. Procedendo in questa disamina, nel Capitolo 3 è illustrata una particolare applicazione di una metodologia MF (elaborata precedentemente dal prof. Celebre), in scenari molecolari nel cui contesto altri approcci dello stesso tipo denotavano limiti e di coltà. In particolare, sono state investigate le interazioni orientazionali cosiddette 'parzialmente repulsive' tra le molecole, consentendo di 'correlare' direttamente i parametri di biassialità e che compaiono all'interno dell'espressione del potenziale orientazionale, alle propriet à di forma delle particelle (nel caso in questione, schematizzate come mattoncini a simmetria D2h). Ciò può consentire, in linea di principio, di esplorare le conseguenze dell'alterazione dei parametri geometrici molecolari su caratteristiche peculiari del sistema, come le Temperature di transizioni di fase, l'eventuale biassialità delle fasi ecc. Nel corso dello svolgimento del Progetto di Dottorato, è sorta (anche in sinergia con le diverse attività di ricerca all'interno del Laboratorio LX-NMR S.C.An.) una problematica in cui l'apporto delle simulazioni numeriche poteva risultare particolarmente utile. L'interesse era quello di cogliere come sistemi ordinati, composti da particelle elicoidali, potessero impartire un determinato ordine orientazionale a dei piccoli soluti, a loro volta elicoidali, a seconda del senso di avvolgimento delle particelle di solvente. Vista la peculiarità oggettiva (morfologica) delle particelle, i risultati ottenuti potrebbero fungere da banco di prova per un processo di 'enantioriconoscimento' assoluto. Dalle simulazioni abbiamo osservato che talune volte (non sempre. . . ) è possibile discriminare senza ambiguità i due enantiomeri (trattandosi di particelle elicoidali, essi vengono tipicamente individuati mediante i descrittori P ed M), È stato accertato che il veri carsi delle possibilità di enantiodiscriminazione dipende da determinate condizioni (che vengono dettagliatamente discusse nel Capitolo 4). L'idea e le simulazioni numeriche hanno altresì costituito prezioso materiale per un modello MF del fenomeno, in grado di consentire appunto, in linea di principio, la distinzione assoluta dei due enantiomeri (assunta nota l'elicità del solvente) Ciò è reso possibile dalla formulazione di un potenziale orientazionale sensibile alla chiralità, capace di tenere conto del senso di avvolgimento delle particelle elicoidali che si stanno considerando. Il modello elaborato viene presentato e discusso nel Capitolo 5: esso sembra essere particolarmente interessante, avendo anche, a nostro avviso, i requisiti necessari per essere, successivamente, ulteriormente migliorato e 'a nato' per la trattazione di sistemi reali. Per concludere, l'aspetto che maggiormente ci preme sottolineare quale ' loso a' che permea l'intero lavoro di Tesi, è quello di concepire le due metodologie, Molecular Field e Simulazioni Numeriche, come sinergiche (e pertanto non mutuamente esclusive, bensì complementari) una loro corretta applicazione potrebbe condurre il Ricercatore ad ampli carne l'e cacia ed allo stesso tempo aumentare la possibilità di 'innescare' nuove idee sulla base dei dati ottenuti.