20 results on '"Antonino Rizzuti"'
Search Results
2. Three-Disperse Magnetorheological Fluids Based on Ferrofluids Induced Modification of Sedimentation by Addition of Nanoparticles
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Piero Mastrorilli, Michele Dassisti, Antonino Rizzuti, and Giovanna Brunetti
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Ferrofluid ,Materials science ,Sedimentation (water treatment) ,Mechanical Engineering ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Chemical engineering ,Mechanics of Materials ,Magnetorheological fluid ,General Materials Science ,0210 nano-technology - Abstract
The effect of mixing suspended nanoparticles into a bi-disperse magneto-rheological fluid on sedimentation phenomena is explored. A reference bi-disperse MRF has been modified using a ferrofluid containing magnetite nanoparticles of two shapes (spheres or hexagonal platelets) suspended in paraffin-oil as carrier fluid. The reference MRF was prepared with a mixture of two diameter sizes for the micrometric particles. The reference MRF was also prepared using two different grades of carbonyl-iron micrometric particles (herein these will be referred to as HARD and SOFT), which differ each other for their mechanical properties. The experiment monitored the evolution with time of the sediment-supernatant interface. This experiment showed that the presence of nanoparticles (particularly the spherical ones) slows down the sedimentation effects in terms of ratio and rate, independently of the other characteristics of the fluid. This study also showed that fluids based on SOFT carbonyl iron powders, in presence of nanospheres, are more stable than HARD carbonyl iron powder based fluids, since their sedimentation rate slows down in the long term. At the same time, HARD particle-based magnetorheological fluids show smaller sedimentation ratios than SOFT based fluids.
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- 2020
3. Vanadium: A Transition Metal for Sustainable Energy Storing in Redox Flow Batteries
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Michele Dassisti, Piero Mastrorilli, Antonino Rizzuti, G. Cozzolino, M. Chimienti, Abdul-Ghani Olabi, F. Matera, A. Carbone, and Mohamad Ramadan
- Published
- 2022
4. Non-targeted metabolomic approach as a tool to evaluate the chemical profile of sparkling wines fermented with autochthonous yeast strains
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Lorenzo Palombi, Piero Mastrorilli, Vittorio Capozzi, Maria Tufariello, Vito Gallo, Antonino Rizzuti, Francesco Grieco, and Rosa Ragone
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Non targeted ,chemical profile ,autochthonous yeasts ,Saccharomyces cerevisiae ,01 natural sciences ,0404 agricultural biotechnology ,Metabolomics ,Food science ,volatile fraction ,Aroma ,multivariate statistical analysis ,biology ,Chemistry ,010401 analytical chemistry ,food and beverages ,04 agricultural and veterinary sciences ,Yeast strain ,Autochthonous yeasts ,Chemical profile ,Multivariate statistical analysis ,Sparkling wine ,Volatile fraction ,biology.organism_classification ,040401 food science ,Yeast ,0104 chemical sciences ,Correlation analysis ,Fermentation ,sparkling wine ,Food Science ,Biotechnology - Abstract
The Champenoise method for the obtainment of sparkling wines is based on “in bottle” re-fermentation driven by few commercial strains belonging to the Saccharomyces cerevisiae species and their exclusive use can cause a flattening of the sensorial profile. In this work, the impact of native selected yeast strains on the chemical profile of sparkling wines has been evaluated through non-targeted metabolomic approach based on HPLC-HRMS and GC-MS techniques. Results showed that yeast strain affects the levels of i) some fermentative compounds as well as of ii) polysaccharides, organic acids, phenolic acids and lipids. Moreover, a HPLC-HRMS/GC-MS correlation analysis permitted to draw a map that constitutes a useful tool to monitor the different patterns of aroma release. Finally, the present work provide original information to modulate positively the quality of regional sparkling wines from minor autochthonous grape varieties using selected microbial resources.
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- 2021
5. Quality evaluation of table grapes during storage by using 1H NMR, LC-HRMS, MS-eNose and multivariate statistical analysis
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Maria Cefola, Vincenzo Lippolis, Bernardo Pace, Francesco Longobardi, Valentina Innamorato, Vito Gallo, Imperatrice Capotorto, Antonino Rizzuti, Salvatore Cervellieri, and Antonio F. Logrieco
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LC-HRMS ,media_common.quotation_subject ,1H NMR ,HS-SPME/MS-eNose ,Table grape ,Quality evaluation ,Chemometrics ,01 natural sciences ,Analytical Chemistry ,0404 agricultural biotechnology ,Table (landform) ,Quality (business) ,Cultivar ,Mathematics ,media_common ,010401 analytical chemistry ,04 agricultural and veterinary sciences ,General Medicine ,040401 food science ,0104 chemical sciences ,Horticulture ,Proton NMR ,Multivariate statistical ,Food Science - Abstract
Three non-targeted methods, i.e. 1H NMR, LC-HRMS, and HS-SPME/MS-eNose, combined with chemometrics, were used to classify two table grape cultivars (Italia and Victoria) based on five quality levels (5, 4, 3, 2, 1). Grapes at marketable quality levels (5, 4, 3) were also discriminated from non-marketable quality levels (2 and 1). PCA-LDA and PLS-DA were applied, and results showed that, the MS-eNose provided the best results. Specifically, with the Italia table grapes, mean prediction abilities ranging from 87% to 88% and from 98% to 99% were obtained for discrimination amongst the five quality levels and of marketability/non-marketability, respectively. For the cultivar Victoria, mean predictive abilities higher than 99% were achieved for both classifications. Good models were also obtained for both cultivars using NMR and HRMS data, but only for classification by marketability. Satisfying models were further validated by MCCV. Finally, the compounds that contributed the most to the discriminations were identified.
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- 2020
6. A polymer supported palladium(II) β-ketoesterate complex as active and recyclable pre-catalyst for selective reduction of quinolines in water with sodium borohydride
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Piero Mastrorilli, Maria Michela Dell'Anna, Antonino Rizzuti, Cristina Leonelli, Alberto Ferruccio Piccinni, Simona Intini, and Giuseppe Romanazzi
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Recyclable catalyst ,Chemistry ,Process Chemistry and Technology ,Ethylene glycol dimethacrylate ,Inorganic chemistry ,Polymer supported Pd nanoparticles ,chemistry.chemical_element ,Water solvent ,Quinoline transfer hydrogenation ,Methacrylate ,Catalysis ,chemistry.chemical_compound ,Sodium borohydride ,Pd nanoparticles ,Polymer supported ,Copolymer ,Physical and Theoretical Chemistry ,Selective reduction ,Selectivity ,Palladium ,Nuclear chemistry - Abstract
A polymer supported palladium catalyst, obtained by copolymerization of Pd(AAEMA) 2 [AAEMA − = deprotonated form of 2-(acetoacetoxy) ethyl methacrylate] with ethyl methacrylate (co-monomer) and ethylene glycol dimethacrylate (cross-linker), exhibited excellent activity and selectivity for the hydrogenation of quinolines to 1,2,3,4-tetrahydroquinolines in the presence of NaBH 4 as hydrogen donor in water. Both the activity and selectivity could be maintained for at least seven reaction runs. No metal leaching into solution occurred during recycles. TEM analyzes carried out on the catalyst showed that the active species were supported palladium nanoparticles having a mean size of 3 nm, which did not aggregate with the recycles.
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- 2015
7. Mechanical and dynamic-mechanical behavior and morphology of polystyrene/perovskite composites: Effects of filler size
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Roberto Rosa, Antonino Rizzuti, Cristina Leonelli, Pietro Russo, Anna Bonamartini Corradi, and Domenico Acierno
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Filler (packaging) ,Materials science ,Modulus ,Surfaces and Interfaces ,General Chemistry ,Dynamic mechanical analysis ,Condensed Matter Physics ,Viscoelasticity ,Surfaces, Coatings and Films ,chemistry.chemical_compound ,Flexural strength ,chemistry ,Materials Chemistry ,Dynamic-mechanical ,Filler size ,Mechanical ,Morphology ,Perovskite ,Polystyrene nanocomposites ,Chemistry ,Polystyrene ,Composite material ,Dispersion (chemistry) ,Perovskite (structure) - Abstract
Composites based on a commercial grade polystyrene (PS) resin containing non commercial perovskite particles were prepared by melt mixing and analyzed in terms of mechanical properties, dynamic-mechanical behavior and morphology. In particular, with the aim to study the influence of the filler size on the ultimate properties of PS based composites micro- and nano-sized perovskite La0.5Sr0.5MnO3 crystal particles, synthesized by using an efficient and rapid microwave-assisted hydrothermal route, were considered. Measurements of flexural parameters such as modulus and strength by static tests and storage modulus and damping factor by dynamic-mechanical evaluations showed better performance for nanofilled systems with respect to the ones containing micro particles, with the same filler content. Mechanical evidences were explained also by morphological observations from which a different level of filler dispersion seems to be obtained with the organization of perovskite nanosized crystals in superstructures able to support viscoelastic results.
- Published
- 2014
8. Pair distribution function analysis and Mössbauer study of defects in microwave-hydrothermal LiFePO4
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Gabriele Spina, Doretta Capsoni, Marcella Bini, Piercarlo Mustarelli, Stefania Ferrari, Antonino Rizzuti, M. Lantieri, Vincenzo Massarotti, Franco Del Giallo, Cristina Leonelli, Bini, M, Ferrari, S, Capsoni, D, Mustarelli, P, Spina, G, Dela Giallo, F, Lantieri, M, Leonelli, C, Rizzuti, A, and Massarotti, V
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Battery (electricity) ,Cathodes ,Cathode materials ,Olivine ,Pair Distribution Function ,General Chemical Engineering ,Chemistry (all) ,Mossbauer spectroscopy ,Analytical chemistry ,chemistry.chemical_element ,Pair distribution function ,General Chemistry ,Cathode ,Hydrothermal circulation ,law.invention ,Characterization (materials science) ,LiFePO4 ,chemistry ,law ,Mössbauer spectroscopy ,Hydrothermal synthesis ,Chemical Engineering (all) ,Lithium - Abstract
Olivine-type LiFePO4 is nowadays one of the most important cathode materials of choice for highenergy lithium ion batteries. Its intrinsic defectivity, and chiefly the so-called lithium iron anti-site, is one of the most critical issues when envisaging electrochemical applications. This paper reports a combined diffractometric (Synchrotron Radiation XRD with Rietveld and PDF analyses) and spectroscopic (Moessbauer) approach able to give a thorough characterization of the material defectivity. Such analytical procedure has been applied to a sample prepared following an innovative microwave-assisted hydrothermal synthesis route that, in a few minutes, allowed us to obtain a well crystallized material. PDF analysis, which is applied for the first time to this type of battery material, reveals the presence of disorder possibly due to Li/Fe exchange or to a local symmetry lowering. A 5% amount of iron on the lithium site has been detected both by PDF as well as by Moessbauer spectroscopy, which revealed a small percentage of Fe3+ on the regular sites.
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- 2012
9. Ultrafine Magnetite Nanopowder: Synthesis, Characterization, and Preliminary Use as Filler of Polymethylmethacrylate Nanocomposites
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Cristina Leonelli, Domenico Acierno, Roberto Rosa, Antonino Rizzuti, Pietro Russo, Gianfranco Carotenuto, and Mariano Palomba
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microwave-assisted hydrothermal synthesis ,Thermogravimetric analysis ,Materials science ,Nanocomposite ,nanocomposite ,Article Subject ,Nanoparticle ,Maghemite ,engineering.material ,polymethylmethacrylate ,magnetite nanoparticles ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,lcsh:Technology (General) ,engineering ,lcsh:T1-995 ,Magnetic nanoparticles ,General Materials Science ,Thermal stability ,Crystallite ,Composite material ,Magnetite - Abstract
Magnetite (Fe3O4) nanoparticles prepared by microwave-assisted hydrothermal synthesis have been characterized in terms of morphological and structural features. Electron micrographs collected in both scanning (SEM) and transmission (TEM) modes and evaluations of X-ray powder diffraction (XRD) patterns have indicated the achievement of a monodispersed crystallite structure with particles having an average size around 15–20 nm. Structural investigations by Micro-Raman spectroscopy highlighted the obtainment of magnetite nanocrystals with a partial surface oxidation to maghemite (γ-Fe3O4). Preliminary attention has been also paid to the use of these magnetite nanoparticles as filler for a commercial polymethylmethacrylate resin. Hybrid formulations containing up to 3 wt% of nanoparticles were prepared by melt blending and characterized by calorimetric and thermogravimetric tests. For sake of comparison, same formulations containing commercial Fe3O4nanoparticles are also reported. Calorimetric characterization indicates an increase of both glass transition temperature and thermal stability of the nanocomposite systems when loaded with the synthesized magnetite nanoparticles rather then loaded with the same amount of commercial Fe3O4. This first observation represents just one aspect of the promising potentiality offered by the novel magnetic nanoparticles when mixed with PMMA.
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- 2012
10. Enhanced thermal stability in K2O-metakaolin-based geopolymer concretes by Al2O3 and SiO2 fillers addition
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Antonino Rizzuti, Elie Kamseu, D. Perera, and Cristina Leonelli
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Materials science ,Geopolymers ,Mechanical Engineering ,Potassium ,Sintering ,chemistry.chemical_element ,Optical dilatometer ,Grain size ,law.invention ,Geopolymer ,chemistry ,Mechanics of Materials ,law ,General Materials Science ,Thermal stability ,Composite material ,Metakaolin ,Shrinkage - Abstract
Based on the principle of stability of geopolymer gel as refractory binder, a geopolymeric paste in the K2O–Al2O3–SiO2 system was developed and used to produce refractory concretes by adding various amount of α-quartz sand (grain size in the range 0.1 μm to 1 mm) and fine powder alumina (grain size in the range 0.1–100 μm). The consolidated samples were characterized before and after sintering using optical dilatometer, DSC, XRD and SEM. The total shrinkage in the range of 25–900 °C was less than 3%, reduced with respect to the most diffused potassium or sodium based geopolymer systems, which generally records a >5% shrinkage. The maximum shrinkage of the basic geopolymer composition was recorded at 1000 °C with a 17% shrinkage which is reduced to 12% by alumina addition. The temperature of maximum densification was shifted from 1000 °C to 1150 or 1200 °C by adding 75 wt% α-quartz sand or fine powder alumina respectively. The sequences of sintering of geopolymer concretes could be resumed as dehydration, dehydroxylation, densification and finally plastic deformation due to the importance of liquid phase. The geopolymer formulations developed in this study appeared as promising candidates for high-temperature applications: refractory, fire resistant or insulating materials.
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- 2010
11. Structural Characterization of Zirconia Nanoparticles Prepared by Microwave-Hydrothermal Synthesis
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Eugenio Caponetti, D. Chillura Martino, Maria Luisa Saladino, Anna Bonamartini Corradi, Antonino Rizzuti, Cristina Leonelli, Giorgio Nasillo, RIZZUTI, A, LEONELLI, C, CORRADI, A, CAPONETTI, E, CHILLURA MARTINO, DF, NASILLO, G, and SALADINO, M
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Aqueous solution ,Materials science ,nanostructure ,Polymers and Plastics ,Electron microscopy ,nanostructures ,oxides ,surface properties ,Small-angle X-ray scattering ,Nanoparticle ,Mineralogy ,Nanocrystalline material ,Surfaces, Coatings and Films ,Dynamic light scattering ,Chemical engineering ,Transmission electron microscopy ,Hydrothermal synthesis ,Cubic zirconia ,oxide ,Physical and Theoretical Chemistry - Abstract
Nanocrystalline zirconia powders have been prepared by microwave-hydrothermal synthesis starting from aqueous solution of ZrOCl2·8H2O. Results of investigations on the aqueous suspension stability of the washed zirconia nanopowders by dynamic light scattering showed that the suspension, constituted by superaggregates of nanoparticles (131 ± 10 nm), was stable up to 15 days. Nanopowders were investigated by means of transmission electron microscopy and small angle x-ray scattering measurements which proved that the zirconia nanopowder is constituted by small primary nanoparticles of ca. 8 nm that agglomerate forming bigger aggregates of 50 ± 1 nm.
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- 2009
12. Use of noncontact dilatometry for the assessment of the sintering kinetics during mullitization of three kaolinitic clays from Cameroon
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Paolo Veronesi, Antonino Rizzuti, Paola Miselli, Cristina Leonelli, and Elie Kamseu
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Sintering kinetics ,Materials science ,Scanning electron microscope ,nucleation ,Analytical chemistry ,Nucleation ,Sintering ,Mineralogy ,Mullite formation ,Crystal growth ,Mullite ,Condensed Matter Physics ,Noncontact dilatometry ,Differential scanning calorimetry ,Activation energy ,Dilatometer ,Physical and Theoretical Chemistry ,Thermal analysis - Abstract
Noncontact dilatometry, compared to differential scanning calorimetry (DSC), was used together with scanning electron microscopy and densification behavior studies to investigate the parameters that govern the kinetics of transformation of kaolin to mullite during sintering. Three kaolinitc clays from Cameroon, with different SiO2/Al2O3 molar ratio, were examined. The temperatures of mullite nucleation were 973, 979, and 984 °C at 5 °C/min heating rate, respectively, for values of SiO2/Al2O3 molar ratio equal to 4.22, 2.22, and 2.08. At 20 °C/min heating rate, the temperatures are shifted to higher values, 992, 997, and 1,001 °C. The mullitization phenomenon, which includes a first step of nucleation and a second one of crystal growth, presented activation energy in the range of 650–730 kJ/mol, depending on the nature of the sample investigated. These values, obtained by noncontact dilatometer measurements, were comparable to those obtained by means of DSC and are in agreement with literature values. The difference in sintering kinetics for the three kaolinitic clays could explain the different morphologies obtained for the mullite grains.
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- 2009
13. Crystallization of aragonite particles from solution under microwave irradiation
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Antonino Rizzuti and Cristina Leonelli
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Atmospheric pressure ,Scanning electron microscope ,General Chemical Engineering ,Aragonite ,Analytical chemistry ,Mineralogy ,engineering.material ,law.invention ,chemistry.chemical_compound ,Calcium carbonate ,chemistry ,law ,Calcium bicarbonate ,Vaterite ,engineering ,Crystallization ,Microwave ,Morphology ,Polymorphism ,Chemical Engineering (all) ,Physical and Theoretical Chemistry - Abstract
The effect of intense electromagnetic fields, generated inside a multimode microwave applicators, on the crystallization of calcium carbonate polymorphs starting from calcium bicarbonate solutions has been investigated. The identification and quantitative analysis of the calcium carbonate polymorphs has been made by X-ray diffraction using Rietveld-Reference Intensity Ratio (RIR) method. Scanning Electron Microscopy analysis has also been performed to study the morphology of calcium carbonate samples. Crystallization tests have been conducted at atmospheric pressure while adjusting microwave power to maintain solution temperature between 80 °C and 90 °C. For the sake of comparison, calcium carbonate powders have also been prepared using conventional heating either in a oven or on a hot plate with a magnetic stirrer. The experiments conducted using microwave radiation gave in a high percentage yield of aragonite (99%) which has been favoured by increasing microwave exposure times. Low microwave exposure times, on the other hand, favours vaterite formation which crystallized in an unusual flower-like morphology.
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- 2008
14. Sintering behaviour, microstructure and mechanical properties of low quartz content vitrified ceramics using volcanic ash
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Antonino Rizzuti, Cristina Leonelli, U. Chinje Melo, Ndigui Billong, Dino Norberto Boccaccini, Antonella Sola, and Elie Kamseu
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sintering ,Materials science ,Spinel ,Metallurgy ,ash ,Sintering ,Mullite ,engineering.material ,Anorthite ,Microstructure ,Industrial and Manufacturing Engineering ,visual_art ,Ceramics and Composites ,engineering ,visual_art.visual_art_medium ,vitrified ceramics ,Ceramic ,Composite material ,Quartz ,Volcanic ash - Abstract
A complete investigation on the sintering behaviour, involving ceramic transformation, of volcanic ash is reported. Sintering and softening points, vitrification and fusion of finely ground powders of volcanic ash were obtained by hot stage microscope observation. Then, a suitable thermal cycle, which matches the better microstructure and mechanical properties, has been performed. The low quartz content of the final product, the relative high density together with the particular structural complexity of the matrix consequence of the interlocking of various crystalline phases conferred to fired volcanic ash relevant ceramic characteristics. Nucleation and microcrystallisation of pyroxene together with oxidation and cation enrichment are indicated as the main sintering mechanism of fired volcanic ash. Differently from conventional vitrified ceramics, i.e. quartz and mullite in vitreous matrix, the microstructure of the fired products presents spinel, anorthite, diopside, enstatite, pyroferrite, faya...
- Published
- 2008
15. Shape-control by microwave-assisted hydrothermal method for the synthesis of magnetite nanoparticles using organic additives
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Antonino Rizzuti, Nicola Cioffi, Michele Dassisti, Rosaria Anna Picca, Pietro Mastrorilli, Rocco Caliandro, Elisabetta Agostinelli, Gaspare Varvaro, and Maria Chiara Sportelli
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Materials science ,Nanoparticle ,Mineralogy ,Bioengineering ,Crystal growth ,Hydrothermal synthesis ,Magnetic properties ,Magnetite ,Microwave ,Atomic and Molecular Physics, and Optics ,Condensed Matter Physics ,Modeling and Simulation ,Chemistry (all) ,Materials Science (all) ,Hydrothermal circulation ,chemistry.chemical_compound ,Atomic and Molecular Physics ,medicine ,General Materials Science ,Trisodium citrate ,Aqueous solution ,Polyvinylpyrrolidone ,General Chemistry ,chemistry ,Chemical engineering ,and Optics ,medicine.drug - Abstract
A simple and fast microwave-assisted hydrothermal method is proposed for the synthesis of magnetite nanoparticles. The addition of different surfactants (polyvinylpyrrolidone, oleic acid, or trisodium citrate) was studied to investigate the effect on size distribution, morphology, and functionalization of the magnetite nanoparticles. Microwave irradiation at 150 °C for 2 h of aqueous ferrous chloride and hydrazine without additives resulted in hexagonal magnetite nanoplatelets with a facet-to-facet distance of 116 nm and a thickness of 40 nm having a saturation magnetization of ~65 Am2 kg−1. The use of polyvinylpyrrolidone led to hexagonal nanoparticles with a facet-to-facet distance of 120 nm and a thickness of 53 nm with a saturation magnetization of ~54 Am2 kg−1. Additives such as oleic acid and trisodium citrate yielded quasi-spherical nanoparticles of 25 nm in size with a saturation magnetization of ~70 Am2 kg−1 and spheroidal nanoparticles of 60 nm in size with a saturation magnetization up to ~82 Am2 kg−1, respectively. A kinetic control of the crystal growth is believed to be responsible for the hexagonal habit of the nanoparticles obtained without additive. Conversely, a thermodynamic control of the crystal growth, leading to spheroidal nanoparticles, seems to occur when additives which strongly interact with the nanoparticle surface are used. A thorough characterization of the materials was performed. Magnetic properties were investigated by Superconducting Quantum Interference Device and Vibrating Sample magnetometers. Based on the observed magnetic properties, the magnetite obtained using citrate appears to be a promising support for magnetically transportable catalysts.
- Published
- 2015
16. Polyacetylenes Bearing Chiral-Substituted Fluorene and Terfluorene Pendant Groups: Synthesis and Properties
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Piero Mastrorilli, Pio Iannelli, Domenico Acierno, Gian Paolo Suranna, Cosimo Francesco Nobile, Antonino Rizzuti, Eugenio Amendola, Roberto Grisorio, Acierno, Domenico, Mastrorilli, P., Nobile, C. F., Grisorio, R., Rizzati, A., Scranna, G. P., Amendola, E., and Iannelli, P.
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chemistry.chemical_classification ,Photoluminescence ,Polymers and Plastics ,Organic Chemistry ,Terfluorene ,Polymer ,Fluorene ,Inorganic Chemistry ,chemistry.chemical_compound ,Monomer ,chemistry ,Polymerization ,Acetylene ,polyacetylenes ,Polymer chemistry ,Materials Chemistry ,Thermal stability ,Alkyl - Abstract
The synthesis of the first polyacetylenes bearing chiral fluorene-based pendant groups is described. Poly{9,9-bis[(S)-3,7-dimethyloctyl]fluoren-2-ylacetylene} (PFA1), poly{9,9-bis[(S)-2-methylbutyl]fluoren-2-ylacetylene} (PFA2), and poly{9,9,9',9',9'',9''-hexakis[(S)-2-methylbutyl]-7,2';7',2''-terfluoren-2-ylacetylene} (PFA3) have been obtained by Rh(I)-catalyzed polymn. of the corresponding terminal acetylene monomers 2-ethynyl-9,9-bis[(S)-3,7-dimethyloctyl]fluorene , 2-ethynyl-9,9-bis[(S)-2-methylbutyl]fluorene, and 2-ethynyl-9,9,9',9',9'',9''-hexakis[(S)-2-methylbutyl]-7,2';7',2''-terfluorene. The effect of the alkyl chain length at the C-9 position of fluorene on the structural and conformational aspects of the polymers PFA1 and PFA2 as well as on their chiroptical properties was studied by XRD, DSC, TGA, GPC, UV-vis, and CD. A more planar conformation of the polyenic backbone of PFA1 with respect to PFA2 can be inferred by a red shift of the à-à* transition in the UV-vis spectra. Their photoluminescence properties are those typical of fluorene systems. CD measurements evidenced Cotton effects of opposite signs in correspondence of the backbone absorption region, ascribable to an excess of a screw sense of the helical conformations assumed by the two polymers. PFA3 revealed an amorphous structure and exhibited peculiar thermal stability features (as indicated by TGA and DSC). Its emission spectra interest the violet-blue region and do not show any substantial red shift passing from soln. to solid state, thus pointing out an aggregation prevention of terfluorene groups by means of the polyacetylene backbone.
- Published
- 2004
17. Synthesis and catalytic activity of new supported rhodium(I) complexes for the enantioselective hydrogenation of methyl-(Z)-α-N-acetamidocinnamate
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Piero Mastrorilli, Antonino Rizzuti, Giuseppe Romanazzi, Roberto Gobetto, Gian Paolo Suranna, and Cosimo Francesco Nobile
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Stereochemistry ,Ligand ,medicine.drug_class ,Process Chemistry and Technology ,Enantioselective synthesis ,chemistry.chemical_element ,Carboxamide ,Homogeneous catalysis ,Heterogeneous catalysis ,Medicinal chemistry ,Catalysis ,Rhodium ,Enantioselective catalysis, Polymerizable complexes,Rhodium, Supported ,Supported ,Deprotonation ,chemistry ,medicine ,Polymerizable complexes ,Enantioselective catalysis ,Physical and Theoretical Chemistry - Abstract
The polymerizable rhodium complex [(+)-diopRh(AAEMA)] (AAEMA − : deprotonated form of the ligand 2-(acetoacetoxy)-ethylmethacrylate) was obtained by reaction of (cod)Rh(AAEMA) with (+)-diop at −80 °C. Supported chiral complexes have been obtained by copolymerization of [(+)-diopRh(AAEMA)] with N , N -dimethylacrylamide and N , N ′-methylenebisacrylamide or by reaction of [(+)-diopRhCl] 2 with an opportunely prepared poly(β-ketoesterate). Catalytic tests carried out with the homogeneous catalyst or with both its heterogeneous analogues proved to be active in the enantioselective hydrogenation of methyl-( Z )-α- N -acetamidocinnamate yielding ( S )-phenylalanine methylester with ee’s up to 67%.
- Published
- 2002
18. On the use of Ethephon as abscising agent in cv. Crimson Seedless table grape production: combination of Fruit Detachment Force, Fruit Drop and metabolomics
- Author
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Piero Mastrorilli, Antonino Rizzuti, Isabella Cafagna, Luis Manuel Aguilera-Sáez, Giuseppe Ferrara, Vito Gallo, A. Pacifico, Angela Maria Stella Matarrese, and Mario Latronico
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Magnetic Resonance Spectroscopy ,Crimson Seedless ,Nuclear Magnetic Resonance ,Analytical chemistry ,Berry ,Mass Spectrometry ,Analytical Chemistry ,chemistry.chemical_compound ,Metabolomics ,Organophosphorus Compounds ,Plant Growth Regulators ,Table grapes ,Fresh-cut food ,Food Industry ,Vitis ,Flavonoids ,Principal Component Analysis ,Table grape ,Catechin ,General Medicine ,Covariance analysis ,Berry loosening ,Terpenoid ,Horticulture ,chemistry ,Proanthocyanidin ,Fruit ,Fruit Detachment Force ,Tartaric acid ,High Resolution Mass Spectrometry ,Food Science ,Ethephon - Abstract
The effect of 2-chloroethylphosphonic acid (Ethephon, in the following ETH) as abscising agent on cv. Crimson Seedless table grape was investigated by means of Fruit Detachment Force (FDF) and Fruit Drop (FD) analyses combined with a metabolomic study carried out by High Resolution Mass Spectrometry (HRMS) and Nuclear Magnetic Resonance (NMR) spectroscopy. The effectiveness of ETH as abscising agent was ascertained with ETH concentration ranging from 1.4 to 4.0 g/L in a two-year study. The ETH treatments caused berry drops higher than 40% and induced an increase of tartaric acid, procyanidin P2, terpenoid derivatives and peonidin-3-glucoside as well as a decrease of catechin and epicatechin. HRMS–NMR covariance analysis was carried out to correlate the fluctuations of tartaric acid NMR signals to those of MS peaks of the secondary metabolites affected by ETH treatments.
- Published
- 2014
19. Synthesis and copolymerization of rhodium(I) and palladium(II) complexes with the deprotonated form of 2-(acetoacetoxy)ethyl methacrylate
- Author
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Pietro Mastrorilli, Antonino Rizzuti, Gian Paolo Suranna, Maria Michela Dell'Anna, and Cosimo Francesco Nobile
- Subjects
Co-polymerization ,Chemistry ,Inorganic chemistry ,chemistry.chemical_element ,palladium complexes ,Methacrylate ,Rhodium ,Inorganic Chemistry ,rhodium complexes ,Deprotonation ,X-ray photoelectron spectroscopy ,Polymer chemistry ,Materials Chemistry ,Copolymer ,Physical and Theoretical Chemistry ,Palladium - Abstract
The reactions of [(cod)RhCl] 2 (cod=1,5-cyclooctadiene) and Na 2 PdCl 4 with the anion of 2-(acetoacetoxy)ethyl methacrylate (AAEMA − ) afforded (cod)Rh(AAEMA) ( 1 ) and Pd(AAEMA) 2 ( 2 ). Thermal copolymerization of 1 and 2 with suitable comonomers and cross-linkers yielded insoluble resins that have been characterised by elemental analyses, IR, UV–Vis, XPS and SEM techniques and successfully used in the hydrogenation of 1-heptene under mild conditions.
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- 2000
20. Brittle Matrix Composites 9
- Author
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Tatiana Lyashenko, Lech CZARNECKI, Conrado Rodrigues, Flavio De Andrade Silva, Romildo Dias Toledo Filho, Tomasz Ponikiewski, William Weiss, Salah Altoubat, Michał Antoni Glinicki, Barzin Mobasher, Jacek ŚLIWIŃSKI, Zbynek Kersner, Narayanan Neithalath, Beata Łaźniewska-Piekarczyk, Daria Jozwiak-Niedzwiedzka, Grigory Yakovlev, Izabela Hager, Jan Wastiels, Stanislav Seitl, Antonino Rizzuti, Juan Vilches T., Fausto Minelli, Dimitrios Kakogiannis, Alain Sellier, Giovanni Plizzari, Dominik Logoń, Erik Schlangen, Agnieszka Ślosarczyk, Ewa Błazik-Borowa, Janusz Konkol, Waldemar Pichór, Piotr P. Woyciechowski, Omkar Deo, Marta Słowik, Cristina Leonelli, and S P Singh
- Published
- 2009
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