127 research outputs found
MAPLE deposition and characterization of SnO2 colloidal nanoparticle thin films
No full textIn this paper we report on the deposition and characterization of tin oxide (SnO2) nanoparticle thin films. The films were deposited by the matrix-assisted pulsed laser evaporation (MAPLE)
technique. SnO2 colloidal nanoparticles with a trioctylphosphine capping layer were diluted in toluene with a concentration of 0.2 wt% and frozen at liquid nitrogen temperature. The frozen
target was irradiated with a KrF (248 nm, τ = 20 ns) excimer laser (6000 pulses at 10 Hz). The nanoparticles were deposited on silica (SiO2) and Si substrates and submitted to
morphological (high resolution scanning electron microscopy (SEM)), structural Fourier transform infrared spectroscopy (FTIR) and optical (UV–Vis transmission) characterizations.
SEM and FTIR analyses showed that trioctylphosphine was the main component in the as-deposited films. The trioctylphosphine was removed after an annealing in vacuum at
400 ◦C, thus allowing to get uniform SnO2 nanoparticle films in which the starting nanoparticle dimensions were preserved. The energy gap value, determined by optical characterizations, was 4.2 eV, higher than the bulk SnO2 energy gap (3.6 eV), due to quantum confinement effects
Rhetorical Truth: Aristotle (and Gorgias) on Deliberation and Agonism
No full textIn this chapter we will address the relationship between truth and deliberation in Aristotle from the perspective of Rhetoric. In particular, we will bring out the idea that rhetoric, far from being the discipline that ‘says goodbye to truth’—as Plato claimed—has to do with a specific kind of truth of human deliberation, the rhetorical truth, which corresponds to the Aristotelian notion of eikos (‘plausible’ or ‘probable’), whose specific characteristic is that it is by its very nature debatable and refutable. This is one of the reasons why deliberative processes always have an agonistic dimension. The other reason is the fact that - according to Aristotle—logos, in order to produce deliberation, must always involve the sphere of desire (orexis), and that different orexeis produce potential conflict. In the last section of the chapter, we will relate this inherently agonistic and conflictual dimension of deliberative processes in Aristotle’s framework to the thought of Gorgias, an author who is usually seen, rather, in opposition to Aristotle
Madonie, L'arte e la storia
No full textIl volume esamina il patrimonio storico artistico dei seguenti paesi delle Madonie: Caltavuturo, Castelbuono, Cefalù, Collesano, Geraci Siculo, Gangi, Gratteri, Isnello, Petralia Soprana, Petralia Sottana, Polizzi Generosa, Pollina, San Mauro Castelverde e Sclafani Bagni. Per ogni singolo borgo si affronta brevemente la storia della città e successivamente si esaminano le chiese e le opere d’arte ivi contenute, iniziando dalla Chiesa Madre o dalla Basilica per poi continuare con gli altri edifici chiesastici e i palazzi nobiliari. Particolare attenzione viene riservata all’architettura, come le chiese medievali e rinascimentali di Castelbuono, Gratteri e Isnello o quelle barocche e rococò di Petralia Soprana e Polizzi Generosa. In merito alla pittura si affrontano in modo più approfondito i mosaici del bema della Cattedrale di Cefalù, i polittici del Quattro e del Cinquecento di Castelbuono, Petralia Sottana e Polizzi Generosa, le pale d’altare del Sei e del Settecento collocate nelle diverse chiese, i cicli di affreschi e le croci dipinte. Si indaga sia la scultura marmorea, gran parte della quale scolpita dai Gagini e da altri artisti carraresi attivi in Sicilia nel XVI secolo, sia quella lignea, realizzata da artisti locali o provenienti da altre province. Per ogni singola opera si fa riferimento alla letteratura artistica riportando le diverse ipotesi di studio circa l’autore e il periodo. Il volume indaga, inoltre, i musei del territorio, come il Mandralisca di Cefalù, ed i due di Castelbuono e Gibilmanna. La pubblicazione comprende anche le schede biografiche sui più noti artisti madoniti che hanno operato anche in altri centri della Sicilia e della penisola.The volume examines the historical and artistic heritage of the following Madonie villages: Caltavuturo, Castelbuono, Cefalù, Collesano, Geraci Siculo, Gangi, Gratteri, Isnello, Petralia Soprana, Petralia Sottana, Polizzi Generosa, Pollina, San Mauro Castelverde and Sclafani Bagni. For each single village, the history of the city is briefly addressed and then the churches and the works of art contained therein are examined, starting with the Mother Church or the Basilica and then continuing with the other church buildings and noble palaces. Particular attention is paid to architecture, such as the medieval and Renaissance churches of Castelbuono, Gratteri and Isnello or the baroque and rococo ones of Petralia Soprana and Polizzi Generosa. With regard to painting, the mosaics of the bema of the Cathedral of Cefalù, the polyptychs of the fifteenth and sixteenth centuries of Castelbuono, Petralia Sottana and Polizzi Generosa, the altarpieces of the seventeenth and eighteenth centuries placed in the various churches, the cycles of frescoes and the painted crosses. We investigate both the marble sculpture, most of which sculpted by the Gaginis and other Carrara artists active in Sicily in the 16th century, and the wooden one, created by local artists or from other provinces. For each single work, reference is made to the artistic literature, reporting the various hypotheses of study about the author and the period. The volume also investigates the museums of the area, such as the Mandralisca of Cefalù, and the two of Castelbuono and Gibilmanna. The publication also includes biographical notes on the most famous Madonite artists who also worked in other centers of Sicily and the peninsula
Contrast media-induced nephropathy: how has Italy contributed in the past 30 years? A systematic review
No full textBackground and objective: The use of contrast media in Italy has exponentially increased in the past 3 decades. However, it is unknown whether there has been an increase in clinical research evaluating the risks associated with contrast media usage, especially regarding contrast-induced nephropathy. To fill this gap in knowledge, we performed a systematic review. Study eligibility criteria: Meta-analyses, observational studies, and clinical trials assessing contrast media-induced nephropathy as the safety outcome, in which at least one author was affiliated with an Italian university/health care structure, were eligble. Data sources: Ovid MEDLINE, Ovid Embase, Cochrane Methodology Register, and Web of Science were screened. Participants: Men and women exposed to contrast media. Results: In total, 60 original articles were retrieved with an incremental trend between 1990 and 2017. Cohort studies were the most common study design represented. In total, 45 of 60 (75.0%) studies were monocenter studies and 41 of 60 (68.3%) received no funding. In all, 91.7% of studies disclosed no conflicts of interest and 81.7% had no external collaboration. Most of the studies provided a level of evidence of III-2 (32/60; 53.3%) and II (23/60; 38.3%). In total, 50 of 60 studies (83.3%) were published in a scientific journal ranked in the first quartile of their subject area. Conclusion: There was an increased number of studies evaluating contrast-induced nephropathy in Italy during the last three decades. These studies covered procedures to prevent contrast-induced nephropathy or aimed to identify risk factors, biomarkers, and scores, and their related prognosis
“Nato ad essere grandissimo e dalla maledetta fortuna assassinato”: un’opera ritrovata di Cherubino Cornienti, La figlia di Giairo resuscitata dal Salvatore
No full textCherubino Cornienti is undoubtedly one of the few great painters in the italian romantism (like Piccio, Mauro Conconi, Filippo Giuseppini). His international ‘milieu’ beetween Milan and Rome is testify by his friendship with russian master Karl Brjullov. The author rediscover a masterpiece by Cornienti realized in Rome after his apprentice in Milan, The Raising of Jairus Daughter
Gynecology MFM. Volume 5, Issue 6, June 2023, 100944
No full textThe publisher regrets that the CCM Study Group was not included in the author list at the beginning of the manuscript. The group name has now been added along with all the participants within the group to officially recognize the Authorship of all CCM Study Group members. The publisher would like to apologise for any inconvenience caused
A liquid chromatography-mass spectrometry study on the spirocyclization of ninhydrin with the aminothiols
No full text© 2018 Elsevier BV. This manuscript version is made available under the CC-BY-NC-ND 4.0 license:
http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 24 month embargo from date of publication (May 2018) in accordance with the publisher’s archiving policy.Ninhydrin reacts with some aminothiols to form spiranes adducts whose optical and
chromatographic properties have proved to be useful for chiral recognition. Liquid
chromatography-mass spectrometry data along with spectroscopic analysis reveal that under certain
conditions, in addition to the known single-spirane configuration, the spirothiazolidinic complexes
can exist also as double- and mixed double-spiranes. The reaction was exploited to check the
enantiomeric purity of two commercially available dosage form of D-penicillamine and to measure
the aminothiol concentration in the urine sample from a subject under treatment with the drug.
Separation of diastereoisomers was achieved on a C18 column in isocratic mode by using a mixture
of an aqueous solution of formic acid (30 mmol/L)/acetonitrile (90:10, v/v) as a mobile phase.
Diastereoisomers were detected by a fluorescence detector and mass spectrometer in short times
and with a good resolution. Intra- and inter-assay reproducibility were under 4% with an average
recovery of 98%. At a LOD of 0.01%, no evidence of the toxic distomer (L-enantiomer) was found
in the biological sample and drugs
Generically distributed investments on flexible projects and endogenous growth
No full textIn this paper we study an endogenous growth model where investments are (generically) distributed over multi-period flexible projects leading to new capital once completed. Recently developed techniques in dynamic programming are adapted and used to unveil the global dynamics of this model. Based on this analytical ground, several numerical exercises are performed to show the quantitative relevance of the analytical findings with an emphasis on the relation between project features and economic growth and speed of convergence toward the balanced growth path. © 2015 The Author(s
Advanced Nanostructured Transition Metal Oxide Semiconductors for Solar Energy Applications [Elektronisk resurs]
No full textIncreasing energy consumption and its environmental impacts make it necessary to look for alternative energy sources. Solar energy as huge energy source that can cover the terms sustainability is considered as a favorable alternative. Optoelectronic devices like solar cells and photoelectrochemical cells are in very high interest to provide the energy that we need. They can convert solar energy, as a sustainable energy source, to electricity and fuel. Transition metal oxides (TMOs) due to high chemical stability, abundance, facile production and low cost are favorable materials to be used in these optoelectronic applications. In TMOs, d orbitals electrons contribute in forming bonds that gives special magnetic, electronic and geometric characteristics to these materials. They can be synthesized with different types of chemical and physical deposition methods.The electronic properties of TMOs varies from metallic characteristics to electrical insulators. Transition metal oxide semiconductors (TMOSs) are mostly used in optoelectronic devices. Tuning the properties of TMOSs like, composition, morphology, dimensions, crystal structure, improves the performance of the optoelectronic devices. The light absorption, charge carrier mobility, the time scale between charge injection, regeneration and recombination processes are some of the properties critical to exploitation of TMOSs in solar cells and solar fuel technology.In this thesis, we explore the use of nanostructured TMOSs in all-oxide solar cells, photodetectors and photoelectrochemical cells. 1-dimentional heterojunctions of n-type transparent semi-conductive metal oxides (ZnO and TiO2) in conjunction to p-type light absorbing semi-conductive metal oxides (Cu2O and Co3O4) have been tested in all-oxide photodetectors and solar cells. It is shown that the 1-dimentional nanostructured geometry (nanowires, nanotubes) improves the charge separation and charge transport properties. Increasing the surface to volume aspect ratio in nanowires and nanotubes improves the light absorption compare to the thin film geometry. Our ZnO-Cu2O core-shell nanowire photodetector is the fastest visible light photodetector reported till now. Mesoporous NiO photocathode, sensitized with a biomimetic FeFe-catalyst and coumarin C343 dye, was tested in a photoelectrochemical cell for hydrogen production. This system is the first solar fuel device based on a biomimetic FeFe-catalyst and it shows a Faradic efficiency of 50% in hydrogen production. Cobalt catalysts have higher Faradic efficiency but their performance due to hydrolysis in low pH condition is limited. Nanostructured hematite/magnetite film as a photoanode was tested in a photoelectrochemical cell for water splitting. This hybrid electrode improved the photoactivity of the photoelectrochemical cell for water splitting. The main mechanism for the improvement of the functional properties relies with the role of the magnetite phase, which improves the charge carrier mobility of the composite system, compared to pure hematite, which acts as good light absorbing semiconductor.</p
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