Pierluigi STIPA

Pubblicazioni

Pierluigi STIPA

 

178 pubblicazioni classificate nel seguente modo:

Nr. doc. Classificazioni
127 1 Contributo su Rivista
25 4 Contributo in Atti di Convegno (Proceeding)
18 5 Altro
5 2 Contributo in Volume
3 6 Brevetti
Anno
Risorse
2024
An Overview of the Sustainable Recycling Processes Used for Lithium-Ion Batteries
BATTERIES
Autore/i: Marchese, Daniele; Giosue, Chiara; Staffolani, Antunes; Conti, Massimo; Orcioni, Simone; Soavi, Francesca; Cavalletti, Matteo; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: first_pagesettingsOrder Article Reprints Open AccessReview An Overview of the Sustainable Recycling Processes Used for Lithium-Ion Batteries by Daniele Marchese 1,*ORCID,Chiara Giosuè 2,*ORCID,Antunes Staffolani 3,4,5ORCID,Massimo Conti 6,Simone Orcioni 6,Francesca Soavi 3,4,5ORCID,Matteo Cavalletti 1 andPierluigi Stipa 2ORCID 1 MIDAC S.p.A., Via Alessandro Volta 2, Soave, 37038 Verona, Italy 2 Department of Science and Engineering of Matter, Environment and Urban Planning (SIMAU), Polytechnic University of Marche, INSTM Research Unit, 60131 Ancona, Italy 3 Department of Chemistry “Giacomo Ciamician”, Alma Mater Studiorum University of Bologna, 40126 Bologna, Italy 4 ENERCube, Centro Ricerche Energia, Ambiente e Mare, Centro Interdipartimentale per la Ricerca Industriale Fonti Rinnovabili, Ambiente, Mare ed Energia (CIRI-FRAME)—Alma Mater Studiorum University of Bologna, Viale Ciro Menotti, 48, 48122 Marina di Ravenna, Italy 5 National Reference Center for Electrochemical Energy Storage (GISEL)—INSTM, Via G. Giusti 9, 50121 Firenze, Italy 6 Department of Information Engineering (DII), Polytechnic University of Marche, INSTM Research Unit, 60131 Ancona, Italy * Authors to whom correspondence should be addressed. Batteries 2024, 10(1), 27; https://doi.org/10.3390/batteries10010027 Submission received: 25 November 2023 / Revised: 21 December 2023 / Accepted: 6 January 2024 / Published: 11 January 2024 (This article belongs to the Special Issue Toward Next-Generation Rechargeable Lithium-Ion Batteries: Current Status and Future Prospects) Downloadkeyboard_arrow_down Browse Figures Versions Notes Abstract Lithium-ion batteries (LIBs) can play a crucial role in the decarbonization process that is being tackled worldwide; millions of electric vehicles are already provided with or are directly powered by LIBs, and a large number of them will flood the markets within the next 8–10 years. Proper disposal strategies are required, and sustainable and environmental impacts need to be considered. Despite still finding little applicability in the industrial field, recycling could become one of the most sustainable options to handle the end of life of LIBs. This review reports on the most recent advances in sustainable processing for spent LIB recycling that is needed to improve the LIB value chain, with a special focus on green leaching technologies for Co-based cathodes. Specifically, we provide the main state of the art for sustainable LIB recycling processes, focusing on the pretreatment of spent LIBs; we report on Life Cycle Assessment (LCA) studies on the usage of acids, including mineral as well as organic ones; and summarize the recent innovation for the green recovery of valuable metals from spent LIBs, including electrochemical methods. The advantage of using green leaching agents, such as organic acids, which represent a valuable option towards more sustainable recycling processes, is also discussed. Organic acids can, indeed, reduce the economic, chemical, and environmental impacts of LIBs since post-treatments are avoided. Furthermore, existing challenges are identified herein, and suggestions for improving the effectiveness of recycling are defined.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/326161 Collegamento a IRIS

2024
Quantum tunnelling in hafnia-based metal-insulator-metal diodes: atomistic-to-continuum modelling approach and experimental validation
PHYSICA SCRIPTA
Autore/i: Pavoni, Eleonora; Laudadio, Emiliano; Christopher, Hardly Joseph; Zampa, Gian Marco; Russo, Paola; Mohebbi, Elaheh; Mencarelli, Davide; Dragoman, Mircea; Stipa, Pierluigi; Pierantoni, Luca; Aldrigo, Martino
Classificazione: 1 Contributo su Rivista
Abstract: In this work, we present a metal-insulator-metal (MIM) diode, based on quantum tunnelling phenomena. Its model is based on a multilevel modelling approach consisting of atomistic and continuum simulations, fully validated by extensive measurements. The MIM structure comprises a hafnium oxide (or hafnia, HfO2) dielectric layer, less than 4 nm thick and a square contact area of only 4 μm2, placed between two metallic electrodes, namely platinum as the source and titanium as the drain. The current–voltage (I–V) curve has been estimated by Density Functional Theory (DFT) calculations through an optimisation of the interfaces between metals and monoclinic HfO2. The dielectric parameters arising from ab initio computations have then been used as inputs for the successive circuit and electromagnetic simulations. Finally, the multilevel model has been validated with great accuracy, first measuring the I–V characteristics by applying a drain-source voltage between −1 V and +1 V, and then extracting the scattering parameters up to 40 GHz, thus demonstrating that DFT and circuit/electromagnetic simulations match almost perfectly the experimental ones. These outcomes represent the first study of such nanoscale devices investigated by means of a rigorous atomistic-to-continuum approach, providing invaluable information in order to improve fabrication and correctly assess the macroscale performance of nanoelectronics systems.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/326511 Collegamento a IRIS

2024
Towards graphene-based asymmetric diodes: a density functional tight-binding study
NANOSCALE ADVANCES
Autore/i: Mohebbi, Elaheh; Pavoni, Eleonora; Pierantoni, Luca; Stipa, Pierluigi; Hemmetter, Andreas; Laudadio, Emiliano; Mencarelli, Davide
Classificazione: 1 Contributo su Rivista
Abstract: Self-consistent charge density functional tight-binding (DFTB) calculations have been performed to investigate the electrical properties and transport behavior of asymmetric graphene devices (AGDs). Three different nanodevices constructed of different necks of 8 nm, 6 nm and 4 nm, named Graphene-N8, Graphene-N6 and Graphene-N4, respectively, have been proposed. All devices have been tested under two conditions of zero gate voltage and an applied gate voltage of +20 V using a dielectric medium of 3.9 epsilon interposed between the graphene and the metallic gate. As expected, the results of AGD diodes exhibited strong asymmetric I(V) characteristic curves in good agreement with the available experimental data. Our predictions implied that Graphene-N4 would achieve great asymmetry (A) of 1.40 at |VDS| = 0.2 V with maximum transmittance (T) of 6.72 in the energy range 1.30 eV. More importantly, while the A of Graphene-N4 was slightly changed by applying the gate voltage, Graphene-N6/Graphene-N8 showed a significant effect with their A increased from 1.20/1.03 under no gate voltage (NGV) to 1.30/1.16 under gate voltage (WGV) conditions. Our results open up unprecedented numerical prospects for designing tailored geometric diodes.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/327579 Collegamento a IRIS

2024
Insights into the interfaces of VO2(M) and VO2(B) polymorphs with different substrates
MATERIALS ADVANCES
Autore/i: Mohebbi, Elaheh; Pavoni, Eleonora; Pierantoni, Luca; Stipa, Pierluigi; Laudadio, Emiliano; Mencarelli, Davide
Classificazione: 1 Contributo su Rivista
Abstract: The phenomena arising at the interface between oxide materials and substrates can fundamentally and practically change the physical and chemical properties of the materials themselves. In this study, we employed density functional theory (DFT) calculations to elucidate the stability and optical properties of VO2(M) and VO2(B) interactions with substrates of sapphire(c-cut), sapphire(r-cut), SrTiO3(001), SrTiO3(111), SrNbO3(001), SrNbO3(111), LaAlO3(c-cut), and LaAlO3(r-cut). The surface calculations showed that the fully relaxed SrTiO3(111) and SrNbO3(001) possess the highest energies of 31.8 eV nm−2 and 21.15 eV nm−2 relative to other slabs, before optimizing with VO2(M) and VO2(B) polymorphs, respectively. The calculated adsorption energy indicated that the interface of VO2(M) and VO2(B) structures showed more stability on SrTiO3(001) and SrTiO3(111), with adsorption energy values of 2.83 eV and 0.91 eV, respectively. Furthermore, the optical absorption properties of the highest and lowest stable interfaces have been evaluated. The outcomes predicted that VO2(M)@SrTiO3(001) and VO2(B)@SrTiO3(111) have their optical adsorption in the visible light range, while VO2(M)@sapphire(c-cut) and VO2(B)@sapphire(c-cut) showed the main adsorption peak in the infrared region.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/327903 Collegamento a IRIS

2024
Band gap and THz optical adsorption of SnSe and SnSe2 nanosheets on graphene: Negative dielectric constant of SnSe
RESULTS IN PHYSICS
Autore/i: Mohebbi, Elaheh; Pavoni, Eleonora; Pierantoni, Luca; Stipa, Pierluigi; Zampa, Gian Marco; Laudadio, Emiliano; Mencarelli, Davide
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/326952 Collegamento a IRIS

2023
In vitro toxicity of short vs long chrysotile fibres
Autore/i: Gualtieri, Alessandro; Mirata, Serena; Almonti, Vanessa; Bassi Anna, Maria; Meo, Chiara; Scarfì, Sonia; Zapparoli, Mauro; Armeni, Tatiana; Cianfruglia, Laura; Marzioni, Daniela; Fantone, Sonia; Tossetta, Giovanni; Stipa, Pierluigi; Laudadio, Emiliano; Sabbatini, Simona; Minnelli, Cristina; DI VALERIO, Silvia; Vaiasicca, Salvatore; Procopio, Antonio; Pugnaloni, Armanda
Classificazione: 1 Contributo su Rivista
Abstract: Chrysotile is a natural hydrous layer silicate that belongs to the serpentine group. Because of its unique asbestiform shape and outstanding physical-chemical properties, chrysotile is still nowadays the most used commercial mineral fibre in the world. This occurs despite the mineral has been classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC). Since the “fibre toxicity paradigm” relies on the fibre size (length L and width W) and biodurability, the present work attempts to shed light on the issue of the toxicity of short vs. long chrysotile fibres by investigating two size-separated batches of chrysotile fibres (L>5 mm and L≤5 mm) of a commercial Russian sample. In parallel, UICC crocidolite and NYAD G wollastonite fibres were used as a positive and a negative carcinogenic standard, respectively. The calculated fibre potential toxicity/pathogenicity index (FPTI) value of the long-fibre chrysotile (2.35) is greater than that of the short-fibre (2.18) predicting a greater potential of toxicity/pathogenicity of the former. The FTPI value of short-fibre chrysotile is greater than that of wollastonite (1.92-2.12) but lower than that of crocidolite (2.67). The theoretical predictions were complemented with in vitro toxicity tests performed in parallel on four different cell types involved in the toxicity of inhaled mineral fibres: alveolar, endothelial, mesothelial cells and macrophages. The results from the MTT and LDH toxicity and ROS production tests are in line with the FPTI prediction. The negative carcinogenic standard wollastonite displays the lower in vitro toxicity score (0.25), while the short-fibre chrysotile presents a higher score (0.43), followed by the long-fibre chrysotile (0.66) and the positive carcinogenic standard crocidolite (0.67).In conclusion, our in vitro acute toxicity results on chrysotile are in line with the FPTI model predictions, indicating that short chrysotile asbestos fibres should not be assimilated to “innocuous dusts”
2023
Stability, phonon calculations, electronic structure, and optical properties of a VO2(M) nanostructure: A comprehensive density functional theory study
FRONTIERS IN MATERIALS
Autore/i: Mohebbi, Elaheh; Pavoni, Eleonora; Mencarelli, Davide; Stipa, Pierluigi; Laudadio, Emiliano; Pierantoni, Luca
Classificazione: 1 Contributo su Rivista
Abstract: This work aimed to precisely evaluate the physical properties of vanadium dioxide (M), particularly the optical characteristics. We employed different exchangecorrelation functionals to determine the phase stability, band gap properties, and optical characteristics of an experimentally recognized monoclinic VO2(M) polymorph. The calculations not only correctly interpreted the VO2(M) origin but also predicted other optical properties including the extinction coefficient (k) and refractive index (n), which have not been reported in experimental measurements. Phonon dispersion calculations confirmed the presence of negative frequencies for acoustic modes in the phononic curves. When the HSE functional correctly reproduced the experimental band gap, here for the first time, our calculations based on PBE and PBEsol yielded non-zero electronic bandgaps of 0.23 and 0.15 eV for bulk VO2(M). Our predictions showed that semilocal functionals can adequately predict the semiconductor properties of VO2(M) and performed better than all previously reported theoretical works on nulled band gaps. In addition to the better prediction of the peak position in the absorption spectra with HSE hybrid functional, this method also reasonably well described the static dielectric constant of 7.54, showing an excellent match to the experimental values. In general, the results of this study reveal that hybrid functionals yield superior outcomes compared to semi-local functionals for optical properties of a VO2(M) polymorph. Our results suggest that the PBEsol + HSE approach allows the efficient characterization of smart materials for electronic and optoelectronic applications.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/312967 Collegamento a IRIS

2023
Amidinoquinoxaline N-oxides: synthesis and activity against anaerobic bacteria
RSC ADVANCES
Autore/i: Gruber, Nadia; Fernández-Canigia, Liliana; Kilimciler, Natalia B.; Stipa, Pierluigi; Bisceglia, Juan A.; García, María B.; Gonzalez Maglio, Daniel H.; Paz, Mariela L.; Orelli, Liliana R.
Classificazione: 1 Contributo su Rivista
Abstract: We present herein an in-depth study on the activity of amidinoquinoxaline N-oxides 1 against Gram-positive and Gram-negative anaerobic bacteria. Based on 5-phenyl-2,3-dihydropyrimidoquinoxaline N-oxide 1a, the selected structural variations included in our study comprise the substituents a- to the N-oxide function, the benzofused ring, substitution and quaternization of the amidine moiety, and the amidine ring size. Compounds 1 showed good to excellent antianaerobic activity, evaluated as the corresponding CIM50 and CIM90 values, and an antimicrobial spectrum similar to metronidazole. Six out of 13 compounds 1 had CIM90 values significantly lower than the reference drug. Among them, imidazoline derivatives 1i-l were the most active structures. Such compounds were synthesized by base-promoted ring closure of the corresponding amidines. The N-oxides under study showed no significant cytotoxicity against RAW 264.7 cells, with high selectivity indexes. Their calculated ADME properties indicate that the compounds are potentially good oral drug candidates. The antianaerobic activity correlated satisfactorily with the electron affinity of the compounds, suggesting that they may undergo bioreductive activation before exerting their antibacterial activity.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/328311 Collegamento a IRIS

2023
Integration of Lipid-Functionalized Epigallocatechin-3-gallate into PLGA Matrix as a Novel Polyphenol-Based Nanoantioxidant
ACS OMEGA
Autore/i: Minnelli, Cristina; Stipa, Pierluigi; Mobbili, Giovanna; Sabbatini, Simona; Romaldi, Brenda; Armeni, Tatiana; Laudadio, Emiliano
Classificazione: 1 Contributo su Rivista
Abstract: The search for polyphenol-based materials with antioxidant activity is a growing research area in the biomedical field. To obtain an efficient and stable nanoantioxidant, a novel biosystem was designed by integrating a lipophilic derivative of epigallocatechin-3-gallate (named EGCG-C18) on the surface of poly(lactic-co-glycolic acid) (PLGA). Poly(vinyl alcohol) (PVA) and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-poly(ethylene glycol) (DSPE-PEG2000) were selected as polymeric and lipidic stabilizers, respectively, and their influence on both physical properties and the antioxidant activity of nanoantioxidant was investigated by a combined in silico and experimental approach. Full-atom molecular dynamics (MD) simulations were carried out to describe the different self-assembly processes of all components and the interactions that guided the EGCG-C18 insertion inside the PLGA matrix. Together with infrared spectroscopy results, the formation of an antioxidant lipid shell on the PLGA surface was clear. Dynamic light scattering and transmission electron microscopy showed that in the presence of DSPE-PEG2000, NPs were smaller than those treated with PVA. In addition, the different stabilizers used strongly influenced the ROS-scavenging ability of nanomaterials and this effect was strictly related to the molecular organization of EGCG-C18. MD showed that the apolar interaction between the alkyl chains of DSPE-PEG2000 and EGCG-C18 oriented the phenolic groups of the polyphenol toward the solvent, providing an ability of NP to scavenge hydroxyl radicals over to free EGCG-C18 and PLGA/PVA NPs. Finally, the ability of nanoantioxidants to protect human dermal fibroblasts from cell death induced by oxidative stress has been tested, revealing the high potential of these novel NPs as polyphenol-based materials.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/325971 Collegamento a IRIS

2023
First principles study of WSe2 and the effect of V doping on the optical and electronic properties
MATERIALS ADVANCES
Autore/i: Pavoni, E.; Mohebbi, E.; Zampa, G. M.; Stipa, P.; Pierantoni, L.; Laudadio, E.; Mencarelli, D.
Classificazione: 1 Contributo su Rivista
Abstract: Tungsten diselenide WSe2 is a material with an intriguing character that has captivated the attention of researchers; in this study, an ab initio analysis is presented that focuses on the optical and electronic properties of WSe2. The study made use of density functional theory (DFT) by employing the Perdew-Burke-Ernzerhof (PBE) generalized gradient approximation (GGA) density functional and PseudoDojo pseudopotential. The study looked at the properties of both bulk and monolayer WSe2 to determine how the number of layers affects the properties of the material. To further investigate the properties of WSe2, four different systems based on vanadium doped-WSe2 were analyzed from the optical and electronic points of view. The systems contained different percentages of V: (i) WSe2:V 1.4%, (ii) WSe2:V 2.8%, (iii) WSe2:V 5.6%, and (iv) WSe2:V 11.2%. The introduction of vanadium brought about a reduction of the bandgap and a global shift of the projected density of states. The valence band maximum (VBM) also crossed the Fermi level, which is consistent with the p-type nature of vanadium doping. Furthermore, the absorption spectra changed in terms of the position and the intensity of the optical transition as a result of vanadium introduction.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/325661 Collegamento a IRIS

2023
Density functional theory and molecular dynamics studies on electrical, mechanical, and thermal properties of TiO2 nanoparticles interacting with poly lactic-co-glycolic acid
COLLOIDS AND SURFACES. A, PHYSICOCHEMICAL AND ENGINEERING ASPECTS
Autore/i: Laudadio, Emiliano; Mohebbi, Elaheh; Pavoni, Eleonora; Minnelli, Cristina; Sabbatini, Simona; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: Poly-lactic poly-co-glycolic acid (PLGA) copolymer is widely used thanks to its biocompatibility, even if could be difficult to find desirable mechanical properties for the polymer matrix. For this reason, inorganic nanoparticles like titanium dioxide (TiO2) can be used to modulate the mechanical properties of systems maintaining their biological capabilities. In this concern, density functional theory (DFT) and molecular dynamics (MD) simulations have been used to study the absorption phenomena of PLGA on surfaces of I4₁/amd (Anatase), P42/mnm (Rutile), and Pbca (Brookite) polymorphs of TiO2 DFT results showed that Anatase TiO2 is the best choice to absorb PLGA in comparison to the other PLGA-TiO2 surfaces. MD simulations remarked a peculiar stabilization pathway of PLGA-TiO2 with Anatase surface along the MD time and the largest increase in both Young’s and Bulk’s moduli. Finally, the influence of temperature on the mechanical properties of PLGA/A-TiO2 has also been investigated; in particular, MD results revealed that Young’s modulus of nanocomposite and the binding energy decreased by increasing the temperature. The outcomes of the present investigation could be helpful to clarify the potential uses of the PLGA-TiO2 nanocomposites in the biomedical field ranging from bone tissue engineering to drug delivery.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/313852 Collegamento a IRIS

2023
Insights into PLGA-encapsulated epigallocatechin 3-gallate nanoparticles as a new potential biomedical system: A computational and experimental approach
EUROPEAN POLYMER JOURNAL
Autore/i: Minnelli, Cristina; Stipa, Pierluigi; Sabbatini, Simona; Mengucci, Paolo; Mobbili, Giovanna; Galeazzi, Roberta; Armeni, Tatiana; Romaldi, Brenda; Celli, Annamaria; Laudadio, Emiliano
Classificazione: 1 Contributo su Rivista
Abstract: Biodegradable poly-lactic poly-glycolic copolymer (PLGA) represents one of the best strategies adopted to convey small molecules unstable and characterised by a low bioavailability if administered without vehicles. This is the case of Epigallocatechin-3-gallate (EGCG), which is one of the most interesting polyphenols from a biomedical point of view. In this study, the impact of EGCG on PLGA nanoparticles (NPs) properties has been studied underlining the role of the binary PVA/Poloxamer-407 as stabilizer system for obtaining colloidal stable NPs. Characterization has been carried out by dynamic light scattering (DLS), encapsulation efficiency, drug release studies, scanning electron microscopy (SEM) and infrared spectroscopy (IR). Molecular dynamics (MD) simulations have been used to model the PLGA and EGCG systems to understand the behaviour of NPs and the interactions that guided the EGCG encapsulation. The nanodispersions exhibited promising cytotoxic potentials in human lung carcinoma A549 cell lines enhancing the well-known growth inhibitor effect of the free EGCG.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/309751 Collegamento a IRIS

2023
Effect of different pseudopotentials on the phonon frequencies, dielectric constant, and Born effective charge of SnSe and SnSe2 nanostructures: A density functional perturbation theory study
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
Autore/i: Mohebbi, Elaheh; Pavoni, Eleonora; Pierantoni, Luca; Stipa, Pierluigi; Laudadio, Emiliano; Mencarelli, Davide
Classificazione: 1 Contributo su Rivista
Abstract: The choice of the pseudopotentials (PPs) is a crucial step towards an accurate atomistic calculation of physical properties of 2D materials. In this study, based on Density-Functional Perturbation Theory (DFPT), we investigated the dependency of the phonon properties such as phonon frequencies, dielectric constant, Born effective charge, and vibrational modes of SnSe and SnSe2 monolayers to the different types of PPs. On the basis of Generalized Gradient Approximation (GGA) using PBE functional, we computed eight phonon calculations for both lattices in combinations with four different PPs including Normconversing (NC) FHI/HGH, Ultrasoft (USPP), and Standard Solid-State (SSSP), while other parameters like cut-off energy, k-points mesh, and convergence threshold were kept fixed. However, the phonon properties of acoustic and optical phonons were better predicted by USPP and SSSP for phonon dispersion of SnSe and SnSe2, respectively. Regarding the dielectric constant and Bohr effective charge calculations, our results showed that SnSe and SnSe2 structures possess the dielectric tensor of 8.9 and 6.6 along the in-plane direction by using USPP calculations. Our outcomes also revealed less sensitivity of SnSe2 polarization to the type of PPs by applying the electric field. This study recommends USPP and SSSP to further phonon analysis of other semiconductors.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/324392 Collegamento a IRIS

2023
First-principles investigation of interface phenomena in hafnium-based metal–insulator–metal diodes
NANOSCALE ADVANCES
Autore/i: Pavoni, Eleonora; Mohebbi, Elaheh; Stipa, Pierluigi; Pierantoni, Luca; Mencarelli, Davide; Dragoman, Mircea; Aldrigo, Martino; Laudadio, Emiliano
Classificazione: 1 Contributo su Rivista
Abstract: Metal–insulator–metal (MIM) diodes are very interesting in many different applications exploiting environment-friendly renewable energy solutions. Moreover, since the dimensions of such devices are at the nanoscale, the size and the characteristics of their constitutive elements can drastically influence their macroscale performance. As it could be difficult to describe in detail the physical phenomena occurring among materials in nanoscale systems, in this work first-principles calculations have been used to study the structural and electrical properties of three different hafnium oxide (HfO2)-MIM diodes. These devices have been simulated at the atomistic level by interposing 3 nm of HfO2 between drain and source electrodes made of gold and platinum, respectively. The monoclinic and orthorhombic polymorphs of HfO2 have been considered to model different types of MIM diodes, and the interface geometries have been optimized to compute the current–voltage characteristics, reflecting the tunneling mechanisms occurring in such devices. The calculation of the transmission pathways has also been carried out to investigate the effects of atomistic coordinates despite the use of the same material. The results demonstrate the role of the Miller indices of metals and the influence of the HfO2 polymorphs on the MIM properties. In this study, the importance of interface phenomena on the measurable properties of the proposed devices has been investigated in detail.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/313853 Collegamento a IRIS

2023
Insights Into a New Geometric Graphene Diode with Ultrahigh Asymmetry Ratio: A Computational Approach
Proceedings of the IEEE Conference on Nanotechnology
Autore/i: Mohebbi, E.; Pavoni, E.; Pierantoni, L.; Stipa, P.; Laudadio, E.; Mencarelli, D.
Editore: IEEE Computer Society
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: In this study, we introduce a novel concept of the transport properties of three proposed geometric graphene diodes based on self-consistent charge density functional tight-binding method. The calculations have been performed with bias voltages up to a few volts suitable for electronics applications. Geometrical graphene devices based ballistic region exhibited strong nonlinear I(V) characteristic curves as well as desirable current amounts. The results indicated that the graphene Device C with an edge width 5nm and angle of 47° showed an excellent current value of 213 μA at 1.5V, which was higher than other two devices A and B with edge widths 9 nm and 5nm and corresponding angle 61°. A maximum AR of 2.23 has been achieved at a current of 137 μA for Device C, which is among the highest values for a geometric graphene device reported to date. This study provides a pathway for optimizing the graphene diodes to be used as potential applications for energy harvesting devices.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/326753 Collegamento a IRIS

2023
First-Principles Calculation of MoO2 and MoO3 Electronic and Optical Properties Compared with Experimental Data
NANOMATERIALS
Autore/i: Pavoni, Eleonora; Modreanu, MIRCEA GABRIEL; Mohebbi, Elaheh; Mencarelli, Davide; Stipa, Pierluigi; Laudadio, Emiliano; Pierantoni, Luca
Classificazione: 1 Contributo su Rivista
Abstract: MoO3 and MoO2 systems have attracted particular attention for many widespread applications thanks to their electronic and optical peculiarities; from the crystallographic point of view, MoO3 adopts a thermodynamically stable orthorhombic phase (α-MoO3) belonging to the space group Pbmn, while MoO2 assumes a monoclinic arrangement characterized by space group P21/c. In the present paper, we investigated the electronic and optical properties of both MoO3 and MoO2 by using Density Functional Theory calculations, in particular, the Meta Generalized Gradient Approximation (MGGA) SCAN functional together with the PseudoDojo pseudopotential, which were used for the first time to obtain a deeper insight into the nature of different Mo–O bonds in these materials. The calculated density of states, the band gap, and the band structure were confirmed and validated by comparison with already available experimental results, while the optical properties were validated by recording optical spectra. Furthermore, the calculated band-gap energy value for the orthorhombic MoO3 showed the best match to the experimental value reported in the literature. All these findings suggest that the newly proposed theoretical techniques reproduce the experimental evidence of both MoO2 and MoO3 systems with high accuracy.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/314849 Collegamento a IRIS

2023
Effect of Wet and Dry Environments in CNC/MWCNTs/Ag2O Electrically Conductive Films: Material Characterization and Molecular Dynamics Simulation
JOURNAL OF PHYSICAL CHEMISTRY. C
Autore/i: Luzi, Francesca; Angulo Dehesa, Ainhoa; Laudadio, Emiliano; Puglia, Debora; Lizundia, Erlantz; Stipa, Pierluigi; Armentano, Ilaria; Torre, Luigi
Classificazione: 1 Contributo su Rivista
Abstract: Electrically-conducting biobased materials present a bright future to be used in high-technological applications including sensors, soft electronics and active packaging. Accordingly, in this work we develop and characterize ternary nanohybrid films combining cellulose nanocrystals (CNC), multi-walled carbon nanotubes (MWCNTs) and silver oxide (Ag2O) nanoparticles. An evaporation-induced self-assembly process is applied to obtain homogenously dispersed free-standing nanocomposite films as proven by electron microscopy observations. Thermogravimetric analyses show that while MWCNTs delay the cleavage of glycosidic linkages of cellulose, Ag2O catalyzed thermodegradation events to render materials with reduced thermal stabilities. The electrical and dielectrical properties of the nanohybrid materials are analysed under completely dry and 53% humidity atmospheres and the results are observed also in the light of the electric modulus. Water increases the conductivity of binary and ternary systems and shift the electric modulus relaxation peak. Finally, full atom molecular dynamics simulations are performed for the first time to better describe the phenomena on interfaces between nanoscale systems, underlying mechanisms for the obtained electrical AC and DC results. Computational results reveal changes in the CNC/MWCNT/Ag2O interactions depending on the water presence, more different types of interactions are found in relation to the type of nanomaterial. The combination of experimental and simulation data here shown sheds further light on the electric conducting mechanism of nanocellulose-based materials with multifunctional properties.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/324776 Collegamento a IRIS

2023
In vitro toxicity of short vs long chrysotile fibres
PERIODICO DI MINERALOGIA
Autore/i: Gualtieri, Alessandro; Mirata, Serena; Almonti, Vanessa; Maria Bassi, Anna; Meo, Chiara; Scarfì, Sonia; Zapparoli, Mauro; Armeni, Tatiana; Cianfruglia, Laura; Marzioni, Daniela; Fantone, Sonia; Tossetta, Giovanni; Stipa, Pierluigi; Laudadio, Emiliano; Sabbatini, Simona; Minnelli, Cristina; DI VALERIO, Silvia; Vaiasicca, Salvatore; Procopio, Antonio; Pugnaloni, Armanda
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/323471 Collegamento a IRIS

2023
Cytotoxicity in vitro of two non-commercial samples of chrysotile and fibrous erionite
PERIODICO DI MINERALOGIA
Autore/i: Pugnaloni, Armanda; DI VALERIO, Silvia; Armeni, Tatiana; Cianfruglia, Laura; Tiano, Luca; Marchegiani, Fabio; Stipa, Pierluigi; Laudadio, Emiliano; Sabbatini, Simona; Minnelli, Cristina; Vaiasicca, Salvatore; Ramini, Debora; Procopio, Antonio D.; Fazioli, Francesca; Francesco Gualtieri, Alessandro
Classificazione: 1 Contributo su Rivista
Abstract: Exposure to naturally occurring asbestos and fibrous erionite can have severe impacts for the human health and cause malignant mesothelioma. The disease burden associated with this exposure is difficult to quantify and is not properly investigated. A characterization of the crystal-chemical-physical properties and toxicity/carcinogenicity of naturally occurring fibres with attention to asbestos and erionite is therefore highly recommended. The present study deals with the in vitro biological effects in MeT5A and A549 human cell lines of two non-commercial asbestos fibres: Valmalenco chrysotile from Central Alps Italy and fibrous erionite from Jersey Nevada, USA, including the standards UICC Chrysotile and UICC crocidolite. Light and scanning electron microscopy (SEM) observations showed morphological cell perturbation of treated cells. SEM-EDAX investigations revealed that the release of chemical components in the culture media affect cell viability. ROS levels increased in accordance with glutathione depletion, witnessing a remarkable cellular stress. Free radical release on pristine fibres was investigated by means of electron paramagnetic resonance (EPR) spin trapping technique and FTIR spectroscopy to characterize the molecular structures of fibres. Results reflect the cytotoxic effects and evidence the different toxicity pathways prompted by these fibre species due to their different crystal assemblages and physical properties.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/323351 Collegamento a IRIS

2022
Tailoring the Barrier Properties of PLA: A State-of-the-Art Review for Food Packaging Applications
POLYMERS
Autore/i: Marano, Stefania; Laudadio, Emiliano; Minnelli, Cristina; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: It is now well recognized that the production of petroleum-based packaging materials has created serious ecological problems for the environment due to their resistance to biodegradation. In this context, substantial research efforts have been made to promote the use of biodegradable films as sustainable alternatives to conventionally used packaging materials. Among several biopolymers, poly(lactide) (PLA) has found early application in the food industry thanks to its promising properties and is currently one of the most industrially produced bioplastics. However, more efforts are needed to enhance its performance and expand its applicability in this field, as packaging materials need to meet precise functional requirements such as suitable thermal, mechanical, and gas barrier properties. In particular, improving the mass transfer properties of materials to water vapor, oxygen, and/or carbon dioxide plays a very important role in maintaining food quality and safety, as the rate of typical food degradation reactions (i.e., oxidation, microbial development, and physical reactions) can be greatly reduced. Since most reviews dealing with the properties of PLA have mainly focused on strategies to improve its thermal and mechanical properties, this work aims to review relevant strategies to tailor the barrier properties of PLA-based materials, with the ultimate goal of providing a general guide for the design of PLA-based packaging materials with the desired mass transfer properties.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/304945 Collegamento a IRIS

2022
Salt effects on mixed composition membranes containing an antioxidant lipophilic edaravone derivative: a computational-experimental study
ORGANIC & BIOMOLECULAR CHEMISTRY
Autore/i: Laudadio, Emiliano; Minnelli, Cristina; Mobbili, Giovanna; Sabbatini, Giulia; Stipa, Pierluigi; Rusciano, Dario; Galeazzi, Roberta
Classificazione: 1 Contributo su Rivista
Abstract: The protection of lipid membranes against oxidation avoids diseases associated with oxidative stress. As a strategy to contrast it, functionalized lipids with antioxidant activity are used to become part of membranes thus protecting them. For this purpose, a lipophilic edaravone derivative has been synthesized, adding a C18 saturated chain to the original structure. The antioxidant activity of C18-Edv has been demonstrated in our previous work. In this study, molecular dynamics simulations have been performed to define the effects of NaCl, MgCl2, KCl, and CaCl2 salts on a palmitoyl-oleoyl-sn-glycero-phosphocholine (POPC) lipid bilayer encapsulating C18-Edv. The results showed how different salts influence POPC lateral diffusion, and the movements of C18-Edv heads, which are antioxidant moieties, were correlate to the ability of C18-Edv molecules to protect membranes. MgCl2 showed a negative impact leading to C18-Edv clusterization and membrane stretching, while KCl and NaCl showed a moderate influence on the mixed lipid membrane structure. CaCl2 increased the exposure of the C18-Edv heads to the lipid–water interface, resulting in the salt with a higher propensity to guarantee protection against radicals in the aqueous phase. Finally, C18-Edv-POPC liposomes have been prepared following the simulation conditions, and then an experimental Oxygen Radical Absorbance Capacity (ORAC) assay has been performed to confirm the in silico predicted results.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/306581 Collegamento a IRIS

2022
FTIR spectroscopy for determination of the raw materials used in wood pellet production
FUEL
Autore/i: Toscano, G.; Maceratesi, V.; Leoni, E.; Stipa, P.; Laudadio, E.; Sabbatini, S.
Classificazione: 1 Contributo su Rivista
Abstract: The research investigates the possibility of distinguishing pellet wood fuels using infrared spectroscopy. It has been applied Attenuated Total Reflectance – Fourier Transform InfraRed (ATR-FTIR) spectroscopy, deemed an analysis technique appropriate for detecting the chemical composition of materials, to determine woody components make up a wood pellet. Considering the large quantities of this solid biofuel on the market, it is necessary to guarantee the safety and traceability aspects of the product, as its origin and source, in addition to the quality parameters indicated by the ISO 17225-2 standards. In this study, a total of 98 samples of the most common wood used for European pellet production, have been selected and collected. This set of samples include also materials coming from the wood industry, as residues of the chemical process. Through clustering analysis Principal component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) techniques applied to spectroscopic analyzer data, it has been seen that ATR-FTIR results provide information on wood pellet typology, hardwood and softwood, and pellet made by woody materials containing high quantity of chemical products like glues.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/297702 Collegamento a IRIS

2022
The Effect of Y Doping on Monoclinic, Orthorhombic, and Cubic Polymorphs of HfO2: A First Principles Study
NANOMATERIALS
Autore/i: Pavoni, Eleonora; Mohebbi, Elaheh; Mencarelli, Davide; Stipa, Pierluigi; Laudadio, Emiliano; Pierantoni, Luca
Classificazione: 1 Contributo su Rivista
Abstract: HfO2 can assume different crystalline structures, such as monoclinic, orthorhombic, and cubic polymorphs, each one characterized by unical properties. The peculiarities of this material are also strongly related to the presence of doping elements in the unit cell. Thus, the present paper has the main purpose of studying and comparing twelve different systems characterized by diverse polymorphs and doping percentages. In particular, three different crystalline structures were considered: the monoclinic P21/c, the orthorhombic Pca21, and the cubic Fm3¯m phases of HfO2. Each one has been studied by using Y as a doping agent with three different contents: 0% Y:HfO2, 8% Y:HfO2, 12% Y:HfO2, and 16% Y:HfO2. For all the systems, density functional theory (DFT) methods based on PBE/GGA, and on the HSE hybrid functionals were used to optimize the geometry as well as to study their optical properties. Depending on the polymorphs, Y affects the formation energy in different ways and causes changes in the optical properties. When the percentage of Y did not exceed 12%, a stabilization of the cubic phase fraction and an increase of the dielectric constant was observed. Additionally, the calculated optical bandgap energies and the refractive index are examined to provide an overview of the systems and are compared with experimental data. The bandgaps obtained are in perfect agreement with the experimental values and show a slight increase as the doping percentage grows, while only minor differences are found between the three polymorphs in terms of both refractive index and optical band gap. The adopted first principles study generates a reasonable prediction of the physical-chemical properties of all the systems, thus identifying the effects of doping phenomena.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/309301 Collegamento a IRIS

2022
Influence of a lipophilic edaravone on physical state and activity of antioxidant liposomes: An experimental and in silico study
COLLOIDS AND SURFACES. B, BIOINTERFACES
Autore/i: Minnelli, C.; Laudadio, E.; Fiorini, R.; Galeazzi, R.; Armeni, T.; Stipa, P.; Rusciano, D.; Mobbili, G.
Classificazione: 1 Contributo su Rivista
Abstract: The influence of a lipophilic derivative of Edaravone (C18Edv) on a POPC liposomal bilayer has been investigated by a combined computational-experimental approach. The order and hydration degree of three different systems composed by 10%, 20% and 40% in w/w percentage of C18Edv respect to POPC were investigated through Molecular Dynamics (MD) simulations and fluorescence spectroscopy experiments. Dynamic Light Scattering measurements showed how the presence of different amounts of C18EdV determines differences on liposome size and stability. The survey revealed that the content of lipophilic antioxidant tunes liposome rigidity and influences cellular uptake and antioxidant activity which are maximized for formulation containing 20% of C18Edv
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/293789 Collegamento a IRIS

2022
Microwave Detection Using Two-Atom-Thick Self-Switching Diodes Based on Quantum Simulations and Advanced Circuit Models
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
Autore/i: Aldrigo, M.; Dragoman, M.; Pelagalli, N.; Laudadio, E.; Zappelli, L.; Iordanescu, S.; Vasilache, D.; Dinescu, A.; Pierantoni, L.; Stipa, P.; Mencarelli, D.
Classificazione: 1 Contributo su Rivista
Abstract: In this article, a two-atom-thick diode based on 2-D materials is presented for microwave detection. The diode consists of a molybdenum disulfide monolayer/graphene monolayer heterojunction transferred onto a silicon/silicon dioxide substrate and patterned by means of nanolithography techniques to obtain a geometrical self-switching diode. The interaction between the two monolayers gives rise to a double-stage device, which behaves as a back-to-back diode in the [-3, +3] V voltage range, and as a tunnel diode when exceeding +10 V. The heterojunction can be reproduced at the wafer scale, thanks to its CMOS compatibility and ease of fabrication, and it can be used efficiently as a microwave detector up to 10 GHz, with the best performance around the ISM 2.45-GHz band. Starting from advanced quantum simulations to predict the dc behavior of the single heterojunction-based channel, the diode was fabricated and fully characterized experimentally. Lastly, a rigorous equivalent circuit model is provided, which relies on the measured scattering parameters at high frequencies and allows treating the diode embedded into a coplanar waveguide line as a two-port lossy device. This way, the device can be exploited in circuit-based numerical tools for the design of complex microwave front ends.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/294141 Collegamento a IRIS

2022
Insights into first-principles characterization of the monoclinic VO2(B) polymorph via DFT + U calculation: electronic, magnetic and optical properties
NANOSCALE ADVANCES
Autore/i: Mohebbi, Elaheh; Pavoni, Eleonora; Mencarelli, Davide; Stipa, Pierluigi; Pierantoni, Luca; Laudadio, Emiliano
Classificazione: 1 Contributo su Rivista
Abstract: We have studied the structural, electronic, magnetic, and optical properties of the VO2(B) polymorph using first-principles calculations based on density functional theory (DFT). This polymorph was found to display four optimized structures namely VO2(B)PP, VO2(B)LP, VO2(B)PPD, and VO2(B)LPD using the generalized gradient approximation (GGA) PBE exchange-correlation functional by including/excluding van der Waals interaction. Our derivation provides a theoretical justification for adding an on-site Coulomb U value in the conventional DFT calculations to allow a direct comparison of the two methods. We predicted a zero bandgap of the VO2(B) structure based on GGA/PBE. However, by GGA/PBE + U, we found accurate bandgap values of 0.76, 0.66, and 0.70 eV for VO2(B)PP, VO2(B)LP, and VO2(B)PPD, respectively. The results obtained from DFT + U were accompanied by a structural transition from the metallic to semiconductor property. Here, we verified the non-magnetic characteristic of the monoclinic VO2(B) phase with some available experimental and theoretical data. However, the debate on the magnetic property of this polymorph remains unresolved. Imaginary and real parts of the dielectric function, as computed with the GGA/PBE functional and the GGA/PBE + U functional, were also reported. The first absorption peaks of all considered geometries in the imaginary part of the dielectric constants indicated that the VO2(B) structure could perfectly absorb infrared light. The computed static dielectric constants with positive values, as derived from the optical properties, confirmed the conductivity of this material. Among the four proposed geometries of VO2(B) in this study, the outcomes obtained by VO2(B)PPD reveal good results owing to the excellent consistency of its bandgap, magnetic and optical properties with other experimental and theoretical observations. The theoretical framework in our study will provide useful insight for future practical applications of the VO2(B) polymorph in electronics and optoelectronics.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/306543 Collegamento a IRIS

2022
Phase Properties of Different HfO2 Polymorphs: A DFT-Based Study
CRYSTALS
Autore/i: Laudadio, Emiliano; Stipa, Pierluigi; Pierantoni, Luca; Mencarelli, Davide
Classificazione: 1 Contributo su Rivista
Abstract: Background: Hafnium Dioxide (HfO2) represents a hopeful material for gate dielectric thin films in the field of semiconductor integrated circuits. For HfO2, several crystal structures are possible, with different properties which can be difficult to describe in detail from an experimental point of view. In this study, a detailed computational approach has been shown to present a complete analysis of four HfO2 polymorphs, outlining the intrinsic properties of each phase on the basis of atomistic displacements. Methods: Density functional theory (DFT) based methods have been used to accurately describe the chemical physical properties of the polymorphs. Corrective Hubbard (U) semi-empirical terms have been added to exchange correlation energy in order to better reproduce the excited-state properties of HfO2 polymorphs. Results: the monoclinic phase resulted in the lowest cohesive energy, while the orthorhombic showed peculiar properties due to its intrinsic ferroelectric behavior. DFT + U methods showed the different responses of the four polymorphs to an applied field, and the orthorhombic phase was the least likely to undergo point defects as oxygen vacancies. Conclusions: The obtained results give a deeper insight into the differences in excited states phenomena in relation to each specific HfO2 polymorph.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/294525 Collegamento a IRIS

2022
The Role of Zr on Monoclinic and Orthorhombic HfxZryO2 Systems: A First-Principles Study
MATERIALS
Autore/i: Pavoni, Eleonora; Mohebbi, Elaheh; Stipa, Pierluigi; Mencarelli, Davide; Pierantoni, Luca; Laudadio, Emiliano
Classificazione: 1 Contributo su Rivista
Abstract: HfO2 shows different polymorphs, including monoclinic and orthorhombic ones, that exhibit singular properties. Moreover, the character of HfO2 is also influenced by the Zr atoms as a doping agent. Here, an extensive study of the monoclinic P21/c and the orthorhombic Pca21 polymorphs of HfO2, Hf0.75Zr0.25O2, and Hf0.5Zr0.5O2 is reported. For all six systems, density functional theory (DFT) methods based on generalized gradient approximations (GGAs) were first used; then the GGA + U method was settled and calibrated to describe the electrical and optical properties of polymorphs and the responses to the oxygen vacancies. Zr had different effects in relation to the polymorph; moreover, the amount of Zr led to important differences in the optical properties of the Pca21 polymorph. Finally, oxygen vacancies were investigated, showing an important modulation of the properties of HfxZryO2 nanostructures. The combined GGA and GGA + U methods adopted in this work generate a reasonable prediction of the physicochemical properties of o- and m-HfxZryO2, identifying the effects of doping phenomena.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/303736 Collegamento a IRIS

2022
Identification of a novel nitroflavone-based scaffold for designing mutant-selective EGFR tyrosine kinase inhibitors targeting T790M and C797S resistance in advanced NSCLC
BIOORGANIC CHEMISTRY
Autore/i: Minnelli, Cristina; Laudadio, Emiliano; Sorci, Leonardo; Sabbatini, Giulia; Galeazzi, Roberta; Amici, Adolfo; Semrau, Marta S.; Storici, Paola; Rinaldi, Samuele; Stipa, Pierluigi; Marcaccio, Massimo; Mobbili, Giovanna
Classificazione: 1 Contributo su Rivista
Abstract: The inhibition of the Epidermal Growth Factor (EGFR) represents one of the most promising strategies in non small cell lung cancer (NSCLC) therapy. The recently identified C797S mutation causes resistance of EGFRL858R/T790M against osimertinib, the latest approved third generation EGFR inhibitor. The identification of small molecules capable of selectively inhibiting the T790M mutations also in the late-onset C797S mutation is a desirable strategy and novel chemical structures might provide new insight in the overcoming resistance mechanisms. Here we report the identification of a novel mutant-selective privileged molecular core; guided by a structure-based drug design, a flavone skeleton has been rationally modified, and a virtual library generated. Reversible EGFR inhibitors targeting both L858R/T790M and L858R/T790M/C797S mutations with a higher affinity with respect to the wild type one are discovered via a three-track virtual screening. Selected hits were synthesized and tested in an activity-based enzyme assay against wild-type EGFR, L858R/T790M, as well as L858R/T790M/C797S. The results showed that a nitroflavone-based compound inhibits the phosphorylation of EGFR mutants at low-micromolar concentration showing selectivity over the wild type ones. Structurally similar flavone analogues have been synthesized and the following inhibition assays underlied the importance of both the presence and position of the nitrophenoxy moiety.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/308602 Collegamento a IRIS

2022
PBEsol/HSE Functional: A promising candidate for Vanadium dioxide (B) characterization
RSC ADVANCES
Autore/i: Mohebbi, Elaheh; Pavoni, Eleonora; Mencarelli, Davide; Stipa, Pierluigi; Pierantoni, Luca; Laudadio, Emiliano
Classificazione: 1 Contributo su Rivista
Abstract: A VO2(B) polymorph has been thoroughly investigated by means of density functional theory (DFT) calculations to evaluate the structure, Raman spectrum, cohesive energy, phonon band structure, an delectronic and optical properties. Among the computed Raman modes, eight of them have been assigned to the VO2(B) structure in full agreement with the corresponding experimental spectra. The minimized structure of the VO2(B) polymorph indicated the presence of negative frequencies in its phonon dispersion curves, confirming the dynamic instability of this material. Herein, the combination of generalized gradient approximation (GGA)/PBEsol with a hybrid HSE functional has been employed to perform ab initio calculations on VO2(B), since the conventional semi-local DFT calculations are believed to underestimate the band gap of materials. By considering the electronic structure calculations, for the first time, we found that the calibration of the PBEsol functional can efficiently model the metallic-like properties of VO2(B) with a band gap of 0.26 eV, while the corresponding electronic bandgap of VO2(B) based on the HSE functional possesses a larger band gap of 0.67 eV. The prediction of optical characteristics of VO2(B) indicated that the optical conductivity of VO2(B) lies in the infrared region of light. This work strongly suggests the combination of GGA/PBEsol with HSE hybrid functionals to carefully describe the physical properties of smart materials exploitable in electronics and optoelectronics applications. The nanostructure of VO2(B) looks promising for IR photodetectors and smart windows applications as a semiconductor material with excellent optical features. It is predicted that in the future VO2(B) will continue to expand the envelope of its capabilities because of its remarkable properties.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/308981 Collegamento a IRIS

2022
The Difficult Marriage of Triarylcorroles with Zinc and Nickel Ions
INORGANIC CHEMISTRY
Autore/i: Naitana, Mario L.; Osterloh, W. Ryan; Di Zazzo, Lorena; Nardis, Sara; Caroleo, Fabrizio; Stipa, Pierluigi; Truong, Khai-Nghi; Rissanen, Kari; Fang, Yuanyuan; Kadish, Karl M.; Paolesse, Roberto
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/307381 Collegamento a IRIS

2021
Insights into the Antioxidant Mechanism of Newly Synthesized Benzoxazinic Nitrones: In Vitro and In Silico Studies with DPPH Model Radical
ANTIOXIDANTS
Autore/i: Marano, Stefania; Minnelli, Cristina; Ripani, Lorenzo; Marcaccio, Massimo; Laudadio, Emiliano; Mobbili, Giovanna; Amici, Adolfo; Armeni, Tatiana; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: Synthetic nitrone spin-traps are being explored as therapeutic agents for the treatment of a wide range of oxidative stress-related pathologies, including but not limited to stroke, cancer, cardiovascular, and neurodegenerative diseases. In this context, increasing efforts are currently being made to the design and synthesis of new nitrone-based compounds with enhanced efficacy. The most researched nitrones are surely the ones related to α-phenyl-tert-butylnitrone (PBN) and 5,5- dimethyl-1-pyrroline N-oxide (DMPO) derivatives, which have shown to possess potent biological activity in many experimental animal models. However, more recently, nitrones with a benzoxazinic structure (3-aryl-2H-benzo[1,4]oxazin-N-oxides) have been demonstrated to have superior antioxidant activity compared to PBN. In this study, two new benzoxazinic nitrones bearing an electron- withdrawing methoxycarbonyl group on the benzo moiety (in para and meta positions respect to the nitronyl function) were synthesized. Their in vitro antioxidant activity was evaluated by two cellular-based assays (inhibition of AAPH-induced human erythrocyte hemolysis and cell death in human retinal pigmented epithelium (ARPE-19) cells) and a chemical approach by means of the α,α-diphenyl-β-picrylhydrazyl (DPPH) scavenging assay, using both electron paramagnetic resonance (EPR) spectroscopy and UV spectrophotometry. A computational approach was also used to investigate their potential primary mechanism of antioxidant action, as well as to rationalize the effect of functionalization on the nitrones reactivity toward DPPH, chosen as model radical in this study. Further insights were also gathered by exploring the nitrone electrochemical properties via cyclic voltammetry and by studying their kinetic behavior by means of EPR spectroscopy. Results showed that the introduction of an electron-withdrawing group in the phenyl moiety in the para position significantly increased the antioxidant capacity of benzoxazinic nitrones both in cell and cell-free systems. From the mechanistic point of view, the calculated results closely matched the experimental findings, strongly suggesting that the H-atom transfer (HAT) is likely to be the primary mechanism in the DPPH quenching.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/291465 Collegamento a IRIS

2021
An exploratory study of the policies and legislative perspectives on the end-of-life of lithium-ion batteries from the perspective of producer obligation
SUSTAINABILITY
Autore/i: Giosuè, Chiara; Marchese, D.; Cavalletti, M.; Isidori, R.; Conti, M.; Orcioni, S.; Ruello, M. L.; Stipa, P.
Classificazione: 1 Contributo su Rivista
Abstract: European self-sufficiency in the battery sector is one of the major EU needs. The key lithiumion batteries (LIBs) materials demand is expected to increase in the next decade as a consequence of the increment in the LIBs production and a massive amount of spent LIBs will flood global markets. Hence, these waste streams would be a potential source of secondary raw materials to be valorized, under the principle of circular economy. European governments first, and then companies in the battery sector second, are addressing many efforts in improving legislation on batteries and accumulators. This study explores the current legislative aspects, the main perspective from the producer’s point of view, and the possibility to guarantee a proper recycle of spent LIBs. A monitoring proposal by means of a survey has been carried out and the Italian context, which has been taken as an example of the European context, and it was used to evaluate the practical implication of the current legislation. The main result of the survey is that a specific identification as well as regulations for LIBs are needed. The benefit from a cradle-to-cradle circular economy is still far from the actual situation but several industrial examples and ongoing European projects show the importance and feasibility of the reuse (e.g., second life) and recycle of LIBs.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/292811 Collegamento a IRIS

2021
Effects of different pre-treatments on the properties of polyhydroxyalkanoates extracted from sidestreams of a municipal wastewater treatment plant
SCIENCE OF THE TOTAL ENVIRONMENT
Autore/i: Palmieri, S.; Tittarelli, F.; Sabbatini, S.; Cespi, M.; Bonacucina, G.; Eusebi, A. L.; Fatone, F.; Stipa, P.
Classificazione: 1 Contributo su Rivista
Abstract: The paper deals with effects of two different widespread extraction methods (conventional extraction and Soxhlet extraction) and four different pre-treatments (homogenization with pressure and with blades, sonication, and impact with glass spheres) on the extraction yields and properties of polyhydroxyalkanoate (PHA) extracted from biomass coming from an innovative process (short-cut enhanced phosphorus and PHA recovery) applied in a real wastewater treatment plant. The results show that the two different extraction processes affected the crystallization degree and the chemical composition of the polymer. On the other hand, the extractive yield was highly influenced by pre-treatments: homogenization provided a 15% more extractive yield than the others. Homogenization, especially at high pressure, proved to be the best pre-treatment also in terms of the purity, visual appearance (transparency and clearness), thermal stability, and mechanical performances of the obtained PHA films. All the PHA films begin to melt long before their degradation temperature (Td > 200 °C): this allows their use in the fields of extrusion or compression moulding.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/291675 Collegamento a IRIS

2021
Prediction of drug-carrier interactions of PLA and PLGA drug-loaded nanoparticles by molecular dynamics simulations
EUROPEAN POLYMER JOURNAL
Autore/i: Stipa, Pierluigi; Marano, Stefania; Galeazzi, Roberta; Minnelli, Cristina; Mobbili, Giovanna; Laudadio, Emiliano
Classificazione: 1 Contributo su Rivista
Abstract: terest due to their potential as an ideal non-toxic vehicle for the delivery of active compounds in a controlled and targeted manner. However, at the stage of academic and industrial development, the lack of regulatory instructions for the assessment and characterization of those nanometric materials is considerably delaying their clinical success if compared to other macroscopic systems (i.e. microparticles). In fact, owing to their high surface area to volume ratio, unwanted interactions between nanoparticles and biological systems may occur, leading to unexpected toxicity. In addition, knowledge of drug-polymer interactions is compulsory, as they can directly affect many fundamental properties, such as the drug-loading ability, nanoparticle size, the drug physical state and stability, as well as the actual drug release profile. In this context, computational methods able to rapidly predict the binding and dynamics between drug molecule and its carrier, and between the carrier and biological systems, are highly desirable to minimize the investment in drug design and development. In this study a full atomistic molecular dynamics simulation approach was validated to investigate biomolecular behaviour of poly (lactic acid) (PLA) and poly (lactic-coglycolic acid) (PLGA) as nanoparticulate drug delivery systems. Both polymer systems have been firstly investigated without drugs to better observe their tendency to interact with aqueous solution, which represents a crucial point for drug delivery systems. Subsequently, simulations were run after the incorporation of drugs. Paracetamol, Prednisolone, and Isoniazid were chosen as model drugs in relation to their different affinity with lipids. Specific interactions between polymers and drugs were considered, and a direct comparison between computational results and experimental evidences found in literature was carried out.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/287681 Collegamento a IRIS

2021
Amidinoquinoxaline-Based Nitrones as Lipophilic Antioxidants
ANTIOXIDANTS
Autore/i: Gruber, Nadia; Orelli, Liliana; Minnelli, Cristina; Mangano, Luca; Laudadio, Emiliano; Mobbili, Giovanna; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: The potential of nitrones (N-oxides) as therapeutic antioxidants is due to their ability to counteract oxidative stress, mainly attributed to their action as radical scavengers toward C- and Ocentered radicals. Among them, nitrones from the amidinoquinoxaline series resulted in interesting derivatives, due to the ease with which it is possible to introduce proper substituents within their structure in order to modulate their lipophilicity. The goal is to obtain lipophilic antioxidants that are able to interact with cell membranes and, at the same time, enough hydrophilic to neutralize those radicals present in a water compartment. In this work, the antioxidant efficacy of a series of amidinoquinoxaline nitrones has been evaluated regarding the oxidation of 2-deoxyribose and lipid peroxidation. The results have been rationalized on the basis of the different possible mechanisms involved, depending on some of their properties, such as lipophilicity, the ability to scavenge free radicals, and to undergo single electron transfer (SET) reactions.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/291464 Collegamento a IRIS

2021
Molecular dynamics simulations of quinine encapsulation into biodegradable nanoparticles: A possible new strategy against Sars-CoV-2
EUROPEAN POLYMER JOURNAL
Autore/i: Stipa, Pierluigi; Marano, Stefania; Galeazzi, Roberta; Minnelli, Cristina; Laudadio, Emiliano
Classificazione: 1 Contributo su Rivista
Abstract: A new coronavirus disease, SARS-CoV-2, has spread into a global pandemic in December 2019. Since no specific therapeutic drugs for treating COVID-19 have been approved by FDA, recent studies suggest that the known antimalarial quinine and its derivatives (chloroquine and hydroxychloroquine) inhibit receptor binding of the viral particles and inhibits the strong “cytokine storm”, which is the main cause of death among infected patients. In particular, the natural alkaloid quinine has shown to possess a better safety profile and greater tolerability compared to its derivatives. Dosage optimization of quinine is still necessary as the currently available dosage forms have controversial pharmacokinetics and safety profiles. Therefore, repurposing quinine dosage forms to improve its pharmacokinetics and safety profile may be necessary to support its use against SARS-CoV-2. In this context, biodegradable/biocompatible polymeric nanoparticles may provide a safe site-specific and controlled quinine delivery, reducing the frequency of drug administration and the dose. In this study, a full atomistic molecular dynamics simulation approach has been used to investigate the use of poly-(glycolic acid) and poly-(lactic acid) and their copolymer poly-(lactic-co-glycolic acid) as potential delivery systems for lipophilic quinine to get insights into the mechanism of quinine encapsulation and release at the atomic/molecular level.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/291646 Collegamento a IRIS

2020
Cellulose Acetate-Graft-Poly (Methyl Methacrylate): A “Graft from” Approach of Nitroxide Mediated Radical Polymerization
JOURNAL OF CHEMICAL ENGINEERING & PROCESS TECHNOLOGY
Autore/i: Vernon, TEBONG MBAH; Celli, A; Cipolletti, R; Sabbatini, S; Stipa, P
Classificazione: 1 Contributo su Rivista
Abstract: Poly (methyl methacrylate) was grafted onto cellulose acetate backbone using a “graft from” of Nitroxide Mediated Radical Polymerization (NMRP). The formation of cellulose acetate-co-poly (methyl methacrylate) using N-tert-butyl- N- (1-diethylphosphono-2,2-dimethylpropyl) (SG1)-nitroxide based macroalkoxyamine system was confirmed by FTIR and NMR analyses. The copolymer exhibited living characteristics as shown by NMR. DSC investigations showed a copolymer with a rich poly (methyl methacrylate) phase around 120°C and a rich cellulose acetate phase at around 175°C.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/276913 Collegamento a IRIS

2020
Recent contributions of EPR to nitrone and nitroxide chemistry
Electron Paramagnetic Resonance: Volume 27
Autore/i: Stipa, Pierluigi
Editore: Victor Chechik, Damien M Murphy, Bela E Bode
Classificazione: 2 Contributo in Volume
Abstract: The present contribution provides an overview of the latest research studies in which Nitrones and Nitroxides are involved in the applications of Electron Paramagnetic Resonance Spectroscopy (EPR) in different fields. Due to the free radical nature of Nitroxides (Aminoxyls), their use in EPR investigations is rather straightforward, while for Nitrones (N-oxides) it relies instead on their use as ‘‘radical scavengers’’, and/or by their use in the EPR Spin Trapping technique. Since the chemistry of both Nitrones and Nitroxides have been extensively described elsewhere, this contribution would only represent an update on some of their most recent application involving EPR spectroscopy.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/285569 Collegamento a IRIS

2020
Monoalkylated Epigallocatechin-3-gallate (C18-EGCG) as Novel Lipophilic EGCG Derivative: Characterization and Antioxidant Evaluation
ANTIOXIDANTS
Autore/i: Minnelli, Cristina; Galeazzi, Roberta; Laudadio, Emiliano; Amici, Adolfo; Rusciano, Dario; Armeni, Tatiana; Cantarini, Mattia; Stipa, Pierluigi; Mobbili, Giovanna
Classificazione: 1 Contributo su Rivista
Abstract: Epigallocatechin-3-gallate (EGCG) has the highest antioxidant activity compared to the others catechins of green tea. However, the beneficial eects are mainly limited by its poor membrane permeability. A derivatization strategy to increase the EGCG interaction with lipid membranes is considered as one feasible approach to expand its application in lipophilic media, in particular the cellular absorption. At this purpose the hydrophilic EGCG was modified by inserting an aliphatic C18 chain linked to the gallate ring by an ethereal bond, the structure determined by NMR (Nuclear Magnetic Resonance) and confirmed by Density Functional Theory (DFT) calculations. The in vitro antioxidant activity of the mono-alkylated EGCG (C18-EGCG) was studied by the DPPH and Thiobarbituric Acid Reactive Substances (TBARS) assays, and its ability to protect cells towards oxidative stress was evaluated in Adult Retinal Pigmented Epithelium (ARPE-19) cells. Molecular Dynamics (MD) simulation and liposomal/buer partition were used to study the interaction of the modified and unmodified antioxidants with a cell membrane model: the combined experimental-in silico approach shed light on the higher anity of C18-EGCG toward lipid bilayer. Although the DPPH assay stated that the functionalization decreases the EGCG activity against free radicals, from cellular experiments it resulted that the lipid moiety increases the antioxidant protection of the new lipophilic derivative.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/275132 Collegamento a IRIS

2020
A Sacrificial PLA Block Mediated Route to Injectable and Degradable PNIPAAm-Based Hydrogels
POLYMERS
Autore/i: Vernon, TEBONG MBAH; Pertici, Vincent; Lacroix, Céline; Verrier, Bernard; Stipa, Pierluigi; Gigmes, Didier; Trimaille, Thomas
Classificazione: 1 Contributo su Rivista
Abstract: Thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm)-based injectable hydrogels represent highly attractive materials in tissue engineering and drug/vaccine delivery but face the problem of long-term bioaccumulation due to non-degradability. In this context, we developed an amphiphilic poly(D,L-lactide)-b-poly(NIPAAm-co-polyethylene glycol methacrylate) (PLA-b- P(NIPAAm-co-PEGMA)) copolymer architecture, through a combination of ring-opening and nitroxide-mediated polymerizations, undergoing gelation in aqueous solution near 30 °C. Complete hydrogel mass loss was observed under physiological conditions after few days upon PLA hydrolysis. This was due to the inability of the resulting P(NIPAAm-co-PEGMA) segment, that contains sufficiently high PEG content, to gel. The copolymer was shown to be non-toxic on dendritic cells. These results thus provide a new way to engineer safe PNIPAAm-based injectable hydrogels with PNIPAAm-reduced content and a degradable feature.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/276914 Collegamento a IRIS

2020
Efficient and versatile modeling of mono-and multi-layer MoS2 field effect transistor
ELECTRONICS
Autore/i: Pelagalli, N.; Laudadio, E.; Stipa, P.; Mencarelli, D.; Pierantoni, L.
Classificazione: 1 Contributo su Rivista
Abstract: Two-dimensional (2D) materials with intrinsic atomic-level thicknesses are strong candidates for the development of deeply scaled field-effect transistors (FETs) and novel device architectures. In particular, transition-metal dichalcogenides (TMDCs), of which molybdenum disulfide (MoS2) is the most widely studied, are especially attractive because of their non-zero bandgap, mechanical flexibility, and optical transparency. In this contribution, we present an efficient full-wave model of MoS2-FETs that is based on (1) defining the constitutive relations of the MoS2 active channel, and (2) simulating the 3D geometry. The former is achieved by using atomistic simulations of the material crystal structure, the latter is obtained by using the solver COMSOL Multiphysics. We show examples of FET simulations and compare, when possible, the theoretical results to the experimental from the literature. The comparison highlights a very good agreement.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/284800 Collegamento a IRIS

2020
Microwave applications of zirconium-doped hafnium oxide ferroelectrics: From nanoscale calculations up to experimental results
IEEE MTT-S International Microwave Symposium Digest
Autore/i: Aldrigo, M.; Dragoman, M.; Laudadio, E.; Iordanescu, S.; Modreanu, M.; Povey, I. M.; Nastase, F.; Vulpe, S.; Stipa, P.; Di Donato, A.; Pierantoni, L.; Mencarelli, D.
Editore: Institute of Electrical and Electronics Engineers Inc.
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: In this paper, a systematic approach is reported for the electrical properties investigation of an emerging new class of materials for microwave applications, namely zirconium-doped hafnium oxide (HfZrO) ferroelectrics. Starting from atomistic simulations that take into account both structural and spectroscopic data to determine the interatomic potentials, the dielectric constant for the orthorhombic phase of HfZrO ferroelectrics has been extracted. By employing well-established microwave characterization techniques, the tunability of both effective permittivity and loss tangent of HfZrO for a low DC bias voltage of ±5 V has been verified experimentally. Finally, two microwave applications of thin-film (6-nm-thick) HfZrO-based ferroelectrics have been explored, namely an interdigitated capacitor-like phase shifter and a phased antenna array made of two patch elements working at 2.55 GHz, able to steer its beam of 25° for an applied bias of only ±1 V. These results demonstrate the potential impact that ferroelectric-based microwave circuits with tunable characteristics will have in the future telecommunications systems and, as well, the importance of a rigorous approach for their full chemical, physical and electromagnetic characterization.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/284943 Collegamento a IRIS

2020
Experimental investigation on the durability of a novel lightweight prefabricated reinforced-EPS based construction system
CONSTRUCTION AND BUILDING MATERIALS
Autore/i: D'Orazio, Marco; Stipa, Pierluigi; Sabbatini, Simona; Maracchini, Gianluca
Classificazione: 1 Contributo su Rivista
Abstract: This paper investigates the durability of a low-cost construction system named HOMEDONE developed to realize affordable and also temporary housing solutions. The system is based on the assembly of 3D-reinforced EPS panels externally topped off with a multi-layer rendering system. Similar technologies showed durability issues, especially in hot climates, due to the thermal and hygrometric stresses of the thin finishing layers when coupled to thick EPS panels and exposed to extreme events. For this reason, in this work freeze–thaw and wet/drying-UV aging tests on HOMEDONE panels with different finishing systems have been carried out, monitoring macroscopic, microscopic (ATR-FT-IR analysis) and bond strength variations due to aging. Results have pointed out good mechanical properties of the system and only small color variations of the finishing layer due to UV cycles. Then, HOMEDONE can be considered as a durable option for affordable and temporary housing solutions.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/277420 Collegamento a IRIS

2019
Depth Distribution of Spin-Labeled Liponitroxides within Lipid Bilayers: A Combined EPR and Molecular Dynamics Approach
ACS OMEGA
Autore/i: Laudadio, Emiliano; Galeazzi, Roberta; Mobbili, Giovanna; Minnelli, Cristina; Barbon, Antonio; Bortolus, Marco; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/265831 Collegamento a IRIS

2019
50 Years of Chemistry in the Engineering Faculty: From Free Radicals to Nanosystems
The First Outstanding 50 Years of “Università Politecnica delle Marche” Research Achievements in Physical Sciences and Engineering
Autore/i: Stipa, Pierluigi; Sabbatini, Simona; Pisani, Michela; Cardellini, Liberato
Classificazione: 2 Contributo in Volume
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/278702 Collegamento a IRIS

2019
Optical properties of traditional clay tiles for ventilated roofs and implication on roof thermal performance
JOURNAL OF BUILDING PHYSICS
Autore/i: Di Giuseppe, Elisa; Sabbatini, Simona; Cozzolino, Nikita; Stipa, Pierluigi; D’Orazio, Marco
Classificazione: 1 Contributo su Rivista
Abstract: A remarkable advantage of clay tiles roof coverings in hot climates is the realization of a ventilated air layer between them and the roofing underlay that allows a natural and forced convection through the tiles joints and the channel from eaves to ridge, thus cooling the roof materials. However recently, in many countries, regulatory developments on buildings energy efficiency or buildings sustainability certification protocols are increasingly encouraging the use of alternative strategies, with the aim of reducing the urban heat island (UHI) effect and the buildings’ cooling consumptions. Among them, the use of ‘cool’ materials for roof covering. These mandatory or voluntary measures de facto push the construction products market towards specific directions, risking penalizing traditional components such as clay tiles. This article reports the results of experimental and numerical activities carried out in order to extensively characterize the optical properties of clay tile materials and investigate their impact, also coupled with above sheathing ventilation, on the thermal performance of a ventilated roof under warm-temperate climate. In the first phase of the research, the main optical properties of over 30 different clay products have been experimentally characterized in order to get a clear and extensive picture of such properties for the materials spread in the market. In a second phase, starting from the thermal data collected on an experimental real-scale building, a dynamic energy analysis tool was calibrated and used to perform simulations by varying the optical properties of the roof covering thus assessing the impact on the roof temperatures, also in comparison to a clay tiles roof. The results underline that the use of the above sheathing ventilation obtained through clay tiles is an effective strategy to reduce roof temperatures, even if covering materials are not qualified as ‘cool’, thus impacting on both UHI and indoor comfort.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/258693 Collegamento a IRIS

2019
Synthesis, characterization and antioxidant properties of a new lipophilic derivative of edaravone
ANTIOXIDANTS
Autore/i: Minnelli, C.; Laudadio, E.; Galeazzi, R.; Rusciano, D.; Armeni, T.; Stipa, P.; Cantarini, Mattia; Mobbili, G.
Classificazione: 1 Contributo su Rivista
Abstract: As part of a program aimed to obtain antioxidants able to interact with cell membrane, edaravone (EdV, 3-methyl-1-phenyl-2-pyrazolin-5-one), a well-known free radical scavenger, has been modified by alkylation at its allylic position (4) with a C-18 hydrocarbon chain, and the increased lipophilicity has been determined towards the interaction with liposomes. The obtained derivative has been studied by means of density functional theory (DFT) methods in order to characterize its lowest energy conformers and predict its antioxidant properties with respect to the parent compound EdV. The in vitro antioxidant activity of C18-edaravone was studied by means of the α,α-diphenyl-β-picrylhydrazyl (DPPH) assay and in lipid peroxidation experiments performed on artificial lipid membranes using water-soluble as well as lipid-soluble radical initiators. Moreover, since oxidative stress is involved in numerous retinal degenerative diseases, the ability of C18-edaravone to contrast 2,2-azobis (2-amidinopropane hydrochloride) (AAPH)-induced cell death was assessed in adult retinal pigmented epithelium (ARPE-19) cells. Overall, the results demonstrated that the newly synthesized molecule has a high affinity for lipid membrane, increasing the efficacy of the unmodified edaravone under stress conditions.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/269345 Collegamento a IRIS

2018
Sintesi di nuovi Copolmeri Biodegradabili a base Acrilica per mezzo della Polimerizzazione Radicalica Mediata da Nitrossidi (NMP)
XI Congresso Nazionale AICIng 2018
Autore/i: Mbah, V. T.; Trimaille, T.; Pertici, V.; Gigmes, D.; Cipolletti, R.; Stipa, P.
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/259807 Collegamento a IRIS

2018
Free Radical Polymerization Study on Vegetal Oils
Book of Abstract
Autore/i: Cipolletti, R.; Vannini, M.; Celli, A.; Marchese, P.; Stipa, P.
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/259309 Collegamento a IRIS

2018
Nitroxide Mediated Polymerization and Addition for Synthesis of Novel PNIPAAm-based Biodegradable Copolymers
Book of Abstracts
Autore/i: Mbah, V. T.; Trimaille, T.; Pertici, V.; Stipa, P.; Gigmes, D.
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/259310 Collegamento a IRIS

2017
New lipo-nitroxides as antioxidant agents targeting lipid peroxidation.
SPIN2017_Book_of_Abstracts
Autore/i: Bortolus, Marco; Barbon, Antonio; Galeazzi, Roberta; Laudadio, Emiliano; Minnelli, Cristina; Mobbili, Giovanna; Cipolletti, Roberto; Stipa, Pierluigi
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/258268 Collegamento a IRIS

2017
Features of some Aromatic Heterocyclic Nitrones and Nitroxides
Book of Abstracts (Invited Lecture)
Autore/i: Stipa, Pierluigi
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: Invited keynote oral contribution
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/251117 Collegamento a IRIS

2017
Amidinoquinoxaline N-oxides: spin tapping of O- and C-centered radicals
ORGANIC & BIOMOLECULAR CHEMISTRY
Autore/i: Gruber, Nadia; Orelli, Liliana R.; Cipolletti, Roberto; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: Amidinoquinoxaline N-oxides represent a novel family of heterocyclic spin traps. In this work, their ability to trap O- and C-centered radicals was tested using selected derivatives with different structural modifications. All the studied nitrones were able to trap radicals forming persistent spin adducts, also in the case of OH and OOH radicals which are of wide biological interest as examples of ROS. Adducts stability was mainly attributed to the wide delocalization of the unpaired electron over the whole quinoxaline moiety. The nitroxides spectral parameters (hfccs and g-factors) were analyzed and the results were supported by DFT calculations. N-19 hfccs and g-factors were characteristic of each aminoxyl and could aid in the identification of the trapped radical. The enhanced stability of OH adducts in the employed reaction conditions could be ascribed to their possible stabilization by IHB with two different acceptors: the N-O moiety or the amidine functionality. DFT calculations indicate that the preferred IHB is strongly conditioned by the amidine ring size. While five membered homologues show a clear preference for the IHB with the N-O group, in six membered derivatives this stabilizing interaction is preferentially established with the amidine nitrogen as IHB acceptor.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/250517 Collegamento a IRIS

2017
DFT calculations as a powerful tool for ESR spin trapping experiments
MAGNETIC RESONANCE IN CHEMISTRY
Autore/i: Stipa, Pierluigi; Cipolletti, Roberto
Classificazione: 1 Contributo su Rivista
Abstract: A combined electron spin resonance (ESR) and density functional theory study has been carried out to obtain deeper insight in the reaction mechanism of the photorearrangement of 3‐hydroxyindolic nitrones. Also, in this case, the combination of these techniques constitutes a powerful tool when discriminating between different reaction pathways. In particular, density functional theory calculations played an important role for unraveling the overlapping of signals coming from different species in the ESR spin trapping experiments. In the present study, the computed energies and the corresponding ESR parameters of each possible isomer hypothesized have been considered, taking also into account their different possibilities of intramolecular H‐bond formation. However, the results obtained indicate that the possibility of intramolecular H‐bonding did not play a determinant role in this case.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/246628 Collegamento a IRIS

2016
Liposomi funzionalizzati con mannosio-6-fosfato come Targeted Delivery Systems (TDS)”
Conference Proceedings
Autore/i: Minnelli, Cristina; Armeni, Tatiana; Cianfruglia, Laura; Crucianelli, Emanuela; Galeazzi, Roberta; Laudadio, Emiliano; Mobbili, Giovanna; Pisani, Michela; Stipa, Pierluigi
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/249735 Collegamento a IRIS

2016
New Amidinoquinoxaline Nitrones as Antioxidants
Conference Proceedings
Autore/i: Gruber, Nadia; Orelli, Liliana R.; Cipolletti, Roberto; Stipa, Pierluigi; Sabbatini, Simona; Mobbili, Giovanna; Minnelli, Cristina
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/249694 Collegamento a IRIS

2016
A molecular dynamics investigation of penetration of antioxidant lipid-based nitroxides in lipid bilayer
Conference Proceedings
Autore/i: Galeazzi, Roberta; Laudadio, Emiliano; Massaccesi, Luca; Cristina Minnelli, M.; Mobbili, Giovanna; Stipa, Pierluigi
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/249715 Collegamento a IRIS

2016
A combined EPR-molecular dynamics investigation of penetration of antioxidant lipid-based nitroxides in lipid bi-layer
Conference Proceedings
Autore/i: Laudadio, Emiliano; Galeazzi, Roberta; Minnelli, Cristina; Mobbili, Giovanna; Stipa, Pierluigi
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/249710 Collegamento a IRIS

2015
Liponitroxides: EPR study and their efficacy as antioxidants in lipid membranes
RSC ADVANCES
Autore/i: Mobbili, Giovanna; Crucianelli, Emanuela; Barbon, Antonio; Marcaccio, Massimo; Pisani, Michela; Dalzini, Annalisa; Ussano, Eleonora; Bortolus, Marco; Stipa, Pierluigi; Astolfi, Paola
Classificazione: 1 Contributo su Rivista
Abstract: A series of lipid-functionalized nitroxides having a pyrroline nitroxide moiety linked either to a glycerol or to a steroid unit has been synthesized, and their inclusion inside phospholipid bilayers has been investigated by Electron Paramagnetic Resonance (EPR) spectroscopy. The antioxidant behavior of these nitroxides has been studied in azo-initiator induced lipid peroxidation by means of the Thiobarbituric Acid Reactive Species (TBARS) assay; a correlation with their penetration depth within the bilayer has been found. The possible mechanisms involved in the antioxidant action have been considered, discussed and alternative pathways have been suggested for the synthesized liponitroxides due to their different localization. The steroid derivative is limited to scavenging radicals that are generated in the aqueous phase, while the glycerolipids can also act as chain breaking antioxidants.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/230125 Collegamento a IRIS

2015
The reactivity of manganese dioxide towards different substrates in organic solvents
NEW JOURNAL OF CHEMISTRY
Autore/i: Alberti, Angelo; Astolfi, Paola; Carloni, Patricia; Greci, Lucedio; Rizzoli, Corrado; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: The reactivity of manganese dioxide in organic solvents was studied by reacting commercial manganese dioxide MnO2 with different substrates. The reaction of MnO2 with arylimino, indolinonic and quinolinic aromatic nitroxides gave quinoneimine N-oxides via an electron transfer process followed by oxygen transfer. A reduction potential of 0.9 V vs. NHE was roughly estimated for manganese dioxide in aprotic organic solvents by considering the oxidation potentials of those nitroxides able to react with MnO2. By the reaction with para-anisidine the amine radical cation was initially formed through a simple electron transfer process. In the case of substituted phenols, the isolated products were derived instead from the phenoxy radicals generated via hydrogen transfer or an equivalent process. Finally, the quantitative conversion of triphenylphosphine to triphenylphosphine oxide was explained by oxygen atom transfer in a cyclic intermediate derived from an initial nucleophilic attack of phosphorus on MnO2.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/228387 Collegamento a IRIS

2015
Amidinoquinoxaline N-oxides as novel spin traps
RSC ADVANCES
Autore/i: Nadia, Gruber; Lidia, Piehl; Emilio Rubin de, Celis; Jimena, Díaz; Maria, García; Stipa, Pierluigi; Liliana, Orelli
Classificazione: 1 Contributo su Rivista
Abstract: A novel type of spin traps 1 derived from the pyrimidoquinoxaline N-oxide heterocyclic core is reported. EPR technique was used to evaluate their ability to trap methyl radicals generated in a Fenton reaction in the presence of DMSO. All the synthesized nitrones showed spin trapping properties and the corresponding nitroxides 2 were characterized by EPR. The novel spin traps showed remarkably persistent signals, as evidenced in a competition experiment with DMPO. The addition rate constants leading to the spin adducts (kadd) were determined, and very good correlations were found with steric and electronic parameters of the parent nitrones. The spin adducts decomposition rate constants (kdec) and the corresponding half-life times (t1/2) were also determined. DFT and MP2 calculations were used in order to rationalize the adducts hfccs and the structural factors influencing their addition and decomposition rates.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/205813 Collegamento a IRIS

2015
Amidinoquinoxaline N-Oxides: Spin Trapping of O- and C-Centered Radicals
JPOC Special Issue
Autore/i: Gruber, Nadia; Orelli, Liliana R.; Stipa, Pierluigi
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/249687 Collegamento a IRIS

2014
NEW PYRIMIDOQUINOXALINE NITRONES AS SPIN TRAPS
Autore/i: R., Cipolletti; Stipa, Pierluigi; N., Gruber; L. R., Orelli
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/180102 Collegamento a IRIS

2014
New Pirimidoquinoxaline Nitrones as Radical Scavengers
Book of Abstracts
Autore/i: Roberto, Cipolletti; Stipa, Pierluigi; Nadia, Gruber; Liliana R., Orelli
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/187907 Collegamento a IRIS

2014
STUDIO DI NUOVI N-OSSIDI AMIDINOCHINOSSALINICI COME SPIN TRAP
Autore/i: Roberto, Cipolletti; Stipa, Pierluigi; Nadia, Gruber; Liliana R., Orelli
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/187906 Collegamento a IRIS

2013
Estudio de N-Óxidos de amidinoquinoxalina como atrapadores de Spin novedosos
Autore/i: Roberto, Cipolletti; Stipa, Pierluigi; Nadia, Gruber; Liliana R., Orelli
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/187905 Collegamento a IRIS

2013
Benzoxazinic nitrones and nitroxides as possible antioxidants in biological systems
RSC ADVANCES
Autore/i: Astolfi, Paola; Carloni, Patricia; Marini, MARIA GIOVANNA; Mobbili, Giovanna; Pisani, Michela; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: Benzoxazinic nitrones and nitroxides are good antioxidants in model biological systems (micelles, lipoproteins, proteins, liposomes, sugars). With nitrones, this activity may be attributed to their radical trapping ability, whereas with nitroxides to their radical scavenging properties. In both cases, H-abstraction from the C-2 position of the benzoxazine moiety cannot be ruled out and could, at least in part, account for their antioxidant behaviour. Appropriate DFT calculations have been carried out to better understand the mechanisms of action of the studied compounds.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/136265 Collegamento a IRIS

2013
Reactions of Nitric Oxide and Nitrogen Dioxide with Coenzymes Q: Involvement of the Isoprenic Chain
ORGANIC & BIOMOLECULAR CHEMISTRY
Autore/i: Astolfi, Paola; Laurence, Charles; Didier, Gigmes; Lucedio, Greci; Corrado, Rizzoli; Federico, Sorana; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: The formation of a di-tert-alkyl nitroxide has been observed by Electron Spin Resonance during the exposure of coenzyme CoQ10, in both the oxidized and reduced forms, to nitrogen dioxide (˙NO2) or to nitric oxide (˙NO) in the presence of oxygen. The same kind of nitroxide has been observed also with CoQ1, CoQ3 or with 1-phenyl-3-methyl-2-butene, chosen as model compounds. In all cases, the formation of the nitroxide may be justified only by admitting the involvement of the isoprenic chain of the coenzymes and in particular the addition of ˙NO2 to the double bond. A mechanism which accounts for the formation of the nitroxide as well as the other compounds observed in the reactions is proposed and confirmed by a spectroscopic investigation (FT-IR, 1H NMR, X-ray analysis) and by ESI-MS.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/86373 Collegamento a IRIS

2013
Indolinic nitroxides: evaluation of their potential as universal control agents for nitroxide mediated polymerization
POLYMER CHEMISTRY
Autore/i: Astolfi, Paola; Lucedio, Greci; Stipa, Pierluigi; Corrado, Rizzoli; Cedric, Ysacco; Marion, Rollet; Laurent, Autissier; Antoine, Tardy; Yohann, Guillaneuf; Didier, Gigmes
Classificazione: 1 Contributo su Rivista
Abstract: Indolinic nitroxides derived from 2,2-diphenyl-3-phenylimino-2,3-dihydroindol-1-yloxyl (DPAIO) nitroxide were designed to improve the bulk polymerization of methacrylate derivatives. The corresponding alkoxyamines were prepared by reacting alkyl halide and nitroxide in the presence of tin hydride and PbO2. The replacement of one phenyl ring at the C-2 position on the nitroxide by either a neopentyl or an isopropyl group led to compounds with faster decomposition kinetics and better selectivity for the C–ON bond homolysis. The alkoxyamines derived from these two nitroxides were used to control the polymerization of methyl methacrylate and were also tested for the polymerization of styrene as a model for mono-substituted monomers. The shift of the molar mass distribution during the NMP of styrene showed for the first time that pure homopolymerization of styrene and methacrylate derivatives could be controlled by the same nitroxide, thus opening the way to a universal nitroxide for NMP
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/99862 Collegamento a IRIS

2013
OH Radical Trapping with Benzoxazine nitrones: a combined computational and spectroscopic study.
TETRAHEDRON
Autore/i: Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: The hydroxyl radical addition onto 3-aryl-2H-benzo[1,4]oxazin-4-oxides spin traps yielded very persistent nitroxides. Their EPR spectra showed unusually large splitting due to the trapped OH proton, whose assignment has been possible by means of the isotope exchange technique. A proper DFT study revealed isomeric molecular geometries with possible intramolecular hydrogen bonds (IHB) forming 5- and/or 6-membered rings, allowing to be envisioned relationships between EPR hyperfine coupling constants (h.f.c.c.) and IHB strengths.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/93061 Collegamento a IRIS

2012
New Nitroxide functionalized Lipids with Antioxidant Activity
VIII Convegno Nazionale AICIng - Atti del Convegno
Autore/i: C., Petrocchi; Astolfi, Paola; Carloni, Patricia; Mobbili, Giovanna; Pisani, Michela; Stipa, Pierluigi
Editore: Edi-Ermes
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: A new class of different lipids bearing a nitroxide radical moiety was synthesized and used in the preparation of multilamellar phosphatidylcholine liposomes. Analysis of the corresponding EPR spectra allowed to get information about the distribution of these free radicals within the liposome structure, and the resulting antioxidant activity was measured by means of the TBARS assay. A correlation between the functionalised lipids antioxidant activity, their dipolar moment (computed by DFT) and their EPR features could be envisaged.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/80089 Collegamento a IRIS

2012
Synthesis and Antioxidant Activity of Nitroxide Functionalized Lipids
XI Convegno Nazionale GIRSE & 1st Joint Meeting ARPE-GERPE-GIRSE
Autore/i: Astolfi, Paola; Carloni, Patricia; Mobbili, Giovanna; Petrocchi, C.; Pisani, Michela; Stipa, Pierluigi
Editore: Anna Longo e Maurizio Marrale
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: Liposomes are biodegradable and nonimmunogenic vesicular structures made of amphipatic phospholipids which can encapsulate both hydrophilic and hydrophobic materials; because of their versatility they are used as carriers in drugs and gene delivery systems. Polyunsaturated fatty acids present in the bilayer are susceptible to oxidative damage which can alter some important properties like fluidity and permeability and can cause system delivery destruction. The mechanism of lipids oxidative degradation may involve free radical reactions that lead to changes in the unsaturated systems present and eventually to the degradation of the lipid chains. In order to maintain their physical, chemical and functional properties, liposomes need to be protected by antioxidant compounds that can delay or prevent oxidation upon reaction with radical species. Nitroxide radicals (paramagnetic compounds with the unpaired electron mainly localized on the N-O group) are known to protect biological system against oxidative processes in different media and under different stress conditions. [1] As part of our ongoing research in the field of nitrones [2] and nitroxides [3] as potential antioxidants we synthesized neutral non zwitterionic lipids labeled by nitroxide able to react with radical species. Multilamellar liposomes were prepared by mixing the new lipids with Phosphatidylcholine and their EPR features and antioxidant activity was studied.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/80538 Collegamento a IRIS

2011
Antioxidant effect of nitroxide functionalized lipids in liposomes peroxidation
XXIV Congresso Nazionale della Società Chimica Italiana
Autore/i: Pisani, Michela; Astolfi, Paola; Carloni, Patricia; Mobbili, Giovanna; C., Petrocchi; Stipa, Pierluigi
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: Cominicazione Scientifica al XXIV Congresso Nazionale della Società Chimica Italiana, Lecce (Italy)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/83390 Collegamento a IRIS

2011
Synthesis and Antioxidant Properties of Benzoxanic Nitrones and Nitroxides
XXIV Congresso Nazionale della Società Chimica Italiana
Autore/i: Mobbili, Giovanna; Astolfi, Paola; Carloni, Patricia; M. G., Marini; Pisani, Michela; Stipa, Pierluigi
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/83391 Collegamento a IRIS

2011
Synthesis and Antioxidant Properties of Benzoxanic Nitrones and Nitroxides
Autore/i: Mobbili, Giovanna; Astolfi, Paola; Carloni, Patricia; M. G., Marini; Pisani, Michela; Stipa, Pierluigi
Luogo di pubblicazione: Lecce
Classificazione: 5 Altro
Abstract: Cominicazione Scientifica al XXIV Congresso Nazionale della Società Chimica Italiana, Lecce (Italy)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/62372 Collegamento a IRIS

2011
Benzoxazinic Nitrones and Nitroxides as Antioxidants in Biological Systems
6th International Conference on Nitroxide Radicals “SPIN 2011”
Autore/i: Astolfi, Paola; Carloni, Patricia; M. G., Marini; Mobbili, Giovanna; Pisani, Michela; Stipa, Pierluigi
Luogo di pubblicazione: Marseille
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: Comunicazione Scientifica al 6th International Conference on Nitroxide Radicals "SPIN 2011" - Marseille (France)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/62375 Collegamento a IRIS

2011
Indolinic Nitroxides forr Nitroxide Mediated Polymerization
Autore/i: L., Autissier; Greci, Lucedio; Astolfi, Paola; Stipa, Pierluigi; Y., Guillaneuf; D., Bertin; D., Gigmes
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al 6th International Conference on Nitroxide Radicals "SPIN 2008" - Marseille (France)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/62374 Collegamento a IRIS

2011
Indolinonic Nitroxides as a Backdoor in the evaluation of the Redox Potential of Manganese Dioxide
Autore/i: Greci, Lucedio; Astolfi, Paola; Stipa, Pierluigi; A., Alberti
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al 6th International Conference on Nitroxide Radicals "SPIN 2008" - Marseille (France)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/62414 Collegamento a IRIS

2011
RADICAL INTERMEDIATES IN THE PHOTOREARRANGEMENT OF 3-HYDROXYINDOLIC NITRONES
TETRAHEDRON
Autore/i: Alberti, A.; Astolfi, Paola; Carloni, Patricia; Döpp, D.; Greci, L.; Rizzoli, C.; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: A number of 3-hydroxy substituted indolic nitrones were found to quantitatively photorearrange to (2-benzoylamino)phenyl ketones upon UV-A irradiation. EPR-Spin Trapping experiments suggest that the process, which is believed to proceed via the formation of an oxaziridine, follows a homolytic pathway. Although DFT calculations do not allow to totally exclude alternative routes involving singlet intermediates, they do provide support to the proposed homolytic mechanism, which would be driven by a 1,5-hydrogen transfer subsequent to the oxaziridine ring opening. When this hydrogen transfer was made impossible by methylation of the 3-OH group, a benzoxazine was isolated as the sole reaction product.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/57487 Collegamento a IRIS

2011
Synthesis and Thermal Stability of Benzoxazine Nitroxides
JOURNAL OF ORGANIC CHEMISTRY
Autore/i: Astolfi, Paola; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: A new class of stable nitroxides (aminoxyls) having a 1,4-benzoxazine structure were synthesized and the corresponding thermal stability tested. All derivatives resulted stable in the whole range of temperature employed, except those having a benzyl or a t-butyl group at the -position with respect to the aminoxyl function, which underwent radical fragmentation. Such a behavior allowed a kinetic study, carried out by means of EPR spectroscopy, to determine the corresponding rate constants and activation parameters (Ea). Appropriate DFT calculations were performed for all nitroxides including also the thermally stable ones, in order to study the geometries of the fragmentation Transition States as well as to compute the corresponding Bond Dissociation Enthalpies (BDH), useful for further modeling purposes. The data obtained were interpreted on the basis of the relative stability of the leaving radical, according to the corresponding Ea and BDH, whereas in the case of t-butyl derivatives steric hindrance should play a determinant role, as evidenced by a comparison of the geometric, kinetic and thermodynamic parameters upon the whole series.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/62749 Collegamento a IRIS

2010
Stabilità Termica di Alcossiammine da impiegare nelle Polimerizzazioni Radicaliche
Autore/i: Astolfi, Paola; L., Autissier; D., Gigmes; Greci, Lucedio; Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al 9th Congress of the Italian ESR Group (GIRSE), Rimini (Italy), 2010
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58101 Collegamento a IRIS

2010
Alcoxyamines from Indolinonic Nitroxides as Controllers for Radical Polymerizations
Autore/i: Astolfi, Paola; L., Autissier; D., Gigmes; Greci, Lucedio; Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al Congresso AICING '10, Bressanone (Italy), 2010
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58100 Collegamento a IRIS

2010
Thermal Stability of Alcoxyamines to be used in Radical Polymerizations
Autore/i: Astolfi, Paola; L., Autissier; D., Gigmes; Greci, Lucedio; Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al XXXIII National Congress of the Organic Chemistry Division of the Italian Chemical Society, S. Benedetto del Tronto (Italy), 2010
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58102 Collegamento a IRIS

2009
Thermal stability of a new class of benzoxazine nitroxides
Autore/i: Astolfi, Paola; Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al 7th Meeting of the European Federation of EPR Groups, Antwerp (Belgium)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58240 Collegamento a IRIS

2009
Combining DFT with Epr Spin Trapping
Autore/i: Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al 2nd TheTIS Workshop - Theoretical Tools for In-silico Spectroscopy - Pisa (Italy)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58241 Collegamento a IRIS

2009
Stabilità Termica di una nuova classe di Nitrossidi Radicali a struttura Benzossazinica
Autore/i: Astolfi, Paola; Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al Regional Congress of the Italian Chemical Society “TUMA 2009”, Tirrenia (Italy)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58239 Collegamento a IRIS

2009
12-Crown-4-based amphipatic lipid and corresponding metal cation complexes for gene therapy applications: FT-IR characterization and surface charge determination
JOURNAL OF MOLECULAR STRUCTURE
Autore/i: Bruni, P; Fino, V; Pisani, Michela; Tosi, Giorgio; Stipa, Pierluigi; Ferraris, P; Francescangeli, Oriano
Classificazione: 1 Contributo su Rivista
Abstract: The new lipid 1,2-O-dioleyl-3-O-{2-[(12-crown-4)-methoxy]-ethyl}-sn-glycerol, 12C4L, has been synthesized. This molecule can coordinate different cations that should make the corresponding liposome a good candidate as vector of genetic material for possible applications in gene therapy. An important feature of the molecule is the possibility to modulate the net surface charge of their complexes with metal cations, which is important to provide efficient DNA transfections. The molecule and its complexes with some metal cations (Mg2+, Ca2+, Mn2+) have been characterized by FT-IR spectroscopy and band attributions confirmed by Density Functional Theory calculations. The net surface charge has been determined by Z potential determinations.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/50926 Collegamento a IRIS

2008
Synthesis of Alkoxyamines: A New Method
Autore/i: Astolfi, Paola; D., Bertin; D., Gigmes; Greci, Lucedio; Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al 5th International Conference on Nitroxide Radicals "SPIN 2008" - Ancona (Italy)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58242 Collegamento a IRIS

2008
Applications of the new N07D basis set for the calculation of structural and magnetic properties
Autore/i: V., Barone; P., Cimino; Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al 37th National Congress of Physical Chemistry, Camogli (Italy)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58250 Collegamento a IRIS

2008
Sintesi e caratterizzazione di nuovi nitrossidi stabili a struttura benzossazinica
Autore/i: Astolfi, Paola; M., Marini; Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al 8th Congress of the Italian ESR Group (GIRSE), Giovinazzo (Italy)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58246 Collegamento a IRIS

2008
Unusually Persistent Hydroxyl Spin Adducts
Autore/i: Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al Regional Congress of the Italian Chemical Society “TUMA 2008”, L’Aquila (Italy)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58249 Collegamento a IRIS

2008
Nuovi Vettori Sintetici per la Terapia Genica. Caratterizzazione di 3-O-{2-[(12-Crown-4)-Metossi]Etil}-1,2-O-Dioleil-SN-Glicerolo mediante misure FT-IR e di Potenziale Z
Autore/i: Bruni, Paolo; V., Fino; M., Pisani; Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al Congresso AICING 08, Ischia (Italy)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58248 Collegamento a IRIS

2008
Application of new pbe0/N07D and b3lyp/N07D computational models for the calculation of structural parameters and magnetic tensors
Autore/i: V., Barone; P., Cimino; Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al 5th International Conference on Nitroxide Radicals "SPIN 2008" - Ancona (Italy)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58245 Collegamento a IRIS

2008
On the trapping of hydroxyl radical from the reaction between hypochlorite and hydrogen peroxide
Autore/i: R., Castagna; J. P., Eiserich; M. S., Budamagunta; Stipa, Pierluigi; C. E., Cross; E., Proietti; J. C., Voss; Greci, Lucedio
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al 5th International Conference on Nitroxide Radicals "SPIN 2008" - Ancona (Italy)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58243 Collegamento a IRIS

2008
Diphenylnitroxide and Diphenylamino Derivatives from the Reactions of Nitrogen Monoxide and Nitrogen Dioxide with Nitrosobenzene
Book of Abstract
Autore/i: Astolfi, Paola; Carloni, Patricia; Damiani, Elisabetta; L., Greci; M., Marini; Stipa, Pierluigi
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: Recently, we observed that when nitroarenes were reacted with nitrogen monoxide •NO and nitrogen dioxide •NO2 inside the e.s.r. cavity the signals of the corresponding diphenylnitroxides were detected. In order to better understand the reactivity of these two radical species, •NO and •NO2, which can both have deleterious effects (nitrosative and oxidative stress), we tried to obtain further insights on this reaction by carrying it out also on a macroscale level. The isolated compounds, reported in the Scheme, were all justified through the intermediate formation of a diphenylnitroxide. A mechanism for the reaction is proposed in this communication and it is also supported by the data already reported in the literature concerning the reaction between indolinonic nitroxides and nitric oxide.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/57705 Collegamento a IRIS

2008
Hydroxyl Radical from the reaction between Hypochlorite and Hydrogen Peroxide
ATMOSPHERIC ENVIRONMENT
Autore/i: R., Castagna; J. P., Eiserich; M. S., Budamagunta; Stipa, Pierluigi; C. E., Cross; E., Proietti; J. C., Voss; Greci, Lucedio
Classificazione: 1 Contributo su Rivista
Abstract: We studied the reaction between hypochlorite anion (OCl) and hydrogen peroxide (H2O2) by using spin-trapping agents such as 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) and 5- diethoxy-phosphoryl-5-methyl-1-pyrroline-N-oxide (DEPMPO). The obtained data demonstrate that hydroxyl radical is produced in this reaction. Thus, OCl and H2O2 could assume new relevance in environmental chemistry by representing a potential source of hydroxyl radicals and other oxidant species, such as HO–OCl and OCl radical.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/32153 Collegamento a IRIS

2008
Antioxidants: how they work
Oxidants in Biology: a question of balance
Autore/i: Damiani, Elisabetta; Astolfi, Paola; Carloni, Patricia; Stipa, Pierluigi; Greci, Lucedio
Editore: Springer Science & Business Media
Classificazione: 2 Contributo in Volume
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/50499 Collegamento a IRIS

2008
Reactions of Nitrosoarenes with Nitrogen Monoxide (Nitric Oxide) and Nitrogen Dioxide: Formation of Diarylnitroxides.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
Autore/i: Astolfi, Paola; Carloni, Patricia; Damiani, Elisabetta; Greci, Lucedio; M., Marini; C., Rizzoli; Stipa, Pierluigi
Classificazione: 1 Contributo su Rivista
Abstract: Nitrosoarenes react with nitrogen monoxide (nitric oxide) at room temperature and in aprotic media to afford the corresponding diarylnitroxides by the intermediate formation of N-nitrosoarylnitroxides. However, these latter spin adducts, in contrast with literature reports, have never been detected by us. N-nitrosophenylnitroxide is obtained only in the oxidation of the ammonium salt of N-nitrosophenylhydroxylamine (cupferron) with trace amounts of lead tetraacetate. However, it evolves with time to diphenylnitroxide, as demonstrated by following the reaction course in the ESR cavity, On a macroscale level, the reaction between nitrosobenzene and nitric oxide leads to the formation of N-nitrosodiphenylamine, 4-nitro-N-nitrosodiphenylamine, 4-nitrodiphenylamine and 4,4'-dinitrodiphenylamine, in addition to diphenylnitroxide. Diarylnitroxides are also obtained when nitrosoarenes react with small amounts of nitrogen dioxide; the mechanism of this reaction is proposed and discussed. The structure of 4-nitro-N-nitrosodiphenylamine was determined by X-ray analysis.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/51506 Collegamento a IRIS

2007
3-Aryl-2H-benzo[1,4]oxazin-4-oxides: a mew class of spin traps
Autore/i: Astolfi, Paola; M., Marini; Stipa, Pierluigi
Classificazione: 5 Altro
Abstract: Comunicazione Scientifica al GIRSE-ARPE 1st Joint Meeting, Vietri sul Mare (Italy)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/58251 Collegamento a IRIS




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