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Designed long lived emission from CdSe quantum dots by reversible electronic energy transfer with a surface bound chromophore
Get PDFThe size-tunable emission of luminescent quantum dots (QDs) makes them highly interesting for applications that range from bioimaging to optoelectronics. For the same applications, engineering their luminescence lifetime – in particular, making it longer – would be as important; however, no rational methodology to reach this goal is available to date. Here we describe a strategy to prolong the emission lifetime of QDs by electronic energy shuttling to the triplet excited state of a surface-bound molecular chromophore. To implement this idea we made CdSe QDs of different sizes, and we self-assembled them with a pyrene derivative. We observed that the conjugates exhibit delayed luminescence, with emission decays that are prolonged by more than 3 orders of magnitude compared to the parent CdSe QDs (lifetimes up to 330 s). The mechanism invokes unprecedented reversible quantum dot-to-organic chromophore electronic energy transfer
Le culture dell'Espressionismo Astratto
Get PDFL’Espressionismo Astratto, nato in seguito alla Seconda Guerra Mondiale e sviluppatosi fino a primi anni Cinquanta, deve la sua importanza principalmente al fatto di essere stato ricono-sciuto come la prima corrente artistica tipicamente americana grazie alla quale gli Stati Uniti riuscirono a trasferire la capitale mondiale dell’arte da Parigi a New York. Già dai primi decenni del Novecento va fatto risalire l’agognato obiettivo degli Stati Uniti di giungere ad un’arte americana pura, finalmente liberata dalle dipendenze stilistiche europee. Tuttavia, sebbene l’Espressionismo Astratto abbia incarnato ufficialmente questo ideale, esso non nacque solo dal genio dei suoi esponenti, ma anche e particolarmente in virtù di una contaminazione con altre culture minori. Infatti, in seguito ad una convergenza di fattori politici e culturali gli artisti, affrancatisi progressivamente dai realismi promossi dal governo statunitense e dalle influenze del vecchio continente, si lasciarono ispirare in un primo momento dall’arte e dalla cultura dei Nativi Americani e, successivamente, dal Buddhismo Zen
Crossing Boundaries: Investigating ‘Fair’ in British Parliamentary Debates on Im/migration
Get PDFThe paper is a by-product of a recent, cross-disciplinary research project, aiming at exploring
linguistic and discursive patterns broadly construing ‘justice’ in a highly influential
institutional setting of political discourse, i.e. the British House of Commons, as regards one
of the most complex issues facing today's society: im/migration. Parliamentary language may,
in fact, provide a privileged terrain for analysing the relationship between social practices and
discourse, especially as regards the discussion of key, highly contested issues such as
immigration. Moving from the assumption that justice' is a “human construction” (Walzer
1986; Eriksen 2016) embedded in specific systems of value and beliefs, and that immigration
is “indeed a matter of justice” (Miller 2013: 5), the research investigates select patterns of
‘orientational meanings’ (Lemke 1992; Miller 1999), or evaluative and intersubjective stance
(Martin and White 2005; Thompson and Hunston 2006) being typically construed within this
particular register of political discourse. In particular, the paper focuses on 'fair' a a case
study in a specialised corpus of UK parliamentary debates on the broad topic of
im/migration, thus including issues of asylum and refugee
Potentiality of nanofilled thermoplastic insulation for DC cables and capacitors
Get PDFThis paper presents space charge accumulation characteristics of cable grade and capacitor grade nanostructured polypropylene (PP) materials, providing initial results regarding the electrical properties of nanofilled PP materials belonging to the European project GRIDABLE. This project has the aim to develop DC cable extruded insulation and MV and LV DC capacitor films having enhanced performance with respect to presently used materials. The paper shows that nanostructuration may be beneficial, especially at higher temperature, to improve the capacitor-grade material performance. On the other hand, this work validates the importance of surface functionalization of nanofillers, leading to lower space charge accumulation on DC cable-grade materials
New insights on protective treatments for marble by FIB-SEM
Get PDFIn this study, we investigated by FIB-SEM the microstructure of protective coatings formed by two inorganic treatments (namely, ammonium oxalate and ammonium phosphate solutions), with the aim of identifying the factors limiting the protective efficacy of the coatings and outlining possible improvement strategies. In the case of the oxalate treatment, the resulting layer of whewellite was found to contain vertical channels, which can allow water to reach the marble surface and trigger dissolution. Possible prevention of the formation of these channels by addition of a calcium source to the oxalate solution was attempted, but even micromolar additions led to rapid precipitation in the solution. In the case of the phosphate treatment, the resulting hydroxyapatite and octacalcium phosphate coating was found to be cracked and porous. To prevent cracks and pores, diminishing the ammonium phosphate concentration and adding ethanol to the solution were found to be effective strategies, as cracks were prevented and pores were reduced almost to zero. The resulting protective efficacy of the coating was found to be significantly improved, although still not perfect
Cibo, salute e bellezza nella rappresentazione pittorica
Get PDF[Food, health and beauty in pictorial representation] This essay underlines the relationship between food and social condition by the pictorial representation, in which we can observe also the transformation of the depiction of slimness and fatness over time. Recording the gen-eral homologation of the idea of beauty and its consequences, painting also highlights the physical and psychological problems of nutrition
L’interprétation du dialogue chercheur – opérateur / A interpretação do diálogo pesquisador – operador
Get PDFBasing on Vygotsky’s indirect methods framework, Bakhtin’s translinguistics approach, and the principles of the ergonomics of the activity, we analyze two sequences of self-confrontation between a researcher and an operator. We follow the evolution of the dialogue, without isolating the words and gestures of concrete actions, and we emphasize the signs reflecting people’s involvement in a new activity of interpretation of their professional experience. In this way, we implement the translinguistics advocated by Bakhtin within an approach encompassing the verbal and nonverbal dimensions mobilized in the coproduction of the meaning
Il paesaggio di Alcmena
Get PDFQuesto articolo fa parte dell’ottavo numero dei Quaderni di PsicoArt che include molti dei testi raccolti dieci anni fa da Gianni Scalia e Raffaele Milani: erano gli anni in cui si discuteva assai di paesaggio, natura, ambiente, territorio, luogo, spazio, cercando di comprenderne il senso e il valore, la relazione e l’arricchimento reciproco in un ampio registro semantico. Si dà ora forma ai materiali di quella ricerca, conservandone lo spirito. È un viaggio che muove dal lontano mondo greco-latino e arriva alle tesi romantiche sulla natura inserendovi anche un confronto tra le culture: indiana, cinese, giapponese. Autorevoli studiosi commentano filosofi e scrittori, correnti letterarie e di pensiero della più alta tradizione mondiale, affinché la dignità dell’antico possa significare il futuro
Water stress and Water Vulnerability indicators and maps
Get PDFThis report is related to the MADFORWATER Task 1.2 "Analysis and mapping of Water Stress, Water Vulnerability and potential for water reuse in Egypt, Morocco and Tunisia". The aim of this study is to provide a basis for assessing measures that can improve the agricultural water productivity with a special focus on increasing the re-use of wastewater in agriculture
Off-the-job training and the shifting role of part-time and temporary employment across institutional models. Comparing Italian and British firms
Get PDFThis article investigates intensity and composition of off-the-job training investments of Italian and British firms in relation to their workforce heterogeneity with respect to the presence of non-standard workers. The main purpose is to assess the relationship between off-the-job training volumes and composition and the recourse to the main types of non-standard employment, i.e. temporary and part-time contracts, at firm level. Empirical evidence drawn from national surveys of the two countries shows more similarities than expected in terms of the correlation between non-standard employment and training volumes whilst substantial differences arise when disaggregating training interventions according to the types of skills to be developed. Both institutional settings and the different role of part-time and temporary employment in the labour markets of the two countries contribute to interpretation of results