82 research outputs found
ANIMA, FOLLIA, INTERSOGGETTIVITA: ALCUNE RIFLESSIONI SULL'ANTROPOLOGIA HEGELIANA
No full textThe article aims at analyzing the first part of the Subjective Spirit, namely the
Anthropology, trying to discover the first step of the Spirit in the concept of soul, due to
its intrinsic intersubjectivity. The first paragraph describes Hegel’s concept of soul, which is
characterized by immediacy and indeterminateness. These characters belong to the human
being as a spiritual being. The second paragraph concerns the concept of sensibility, which
is connected to the Nature-Spirit gap. Sensibility is the first form of conceptualization of
alterity. Through sensibility, soul begins to develop itself as subjectivity. This development
is marked by negativity and contradiction. The highest contradiction is discussed in the
third paragraph: insanity as an important moment for the spiritual development. In the
fourth paragraph the author demonstrates that through insanity soul partially recognizes
the immanent and intersubjective relation that constitutes itself
«L’indicibile confusione». Carestia, pratiche e mercantilismi visti da Trieste (1764 e dintorni)
No full textNel 1763 e 1764, per cercare di affrontare la paventata crisi alimentare che si prospettava, il Regno di Napoli si rivolse a Trieste come via per rifornirsi dei cereali provenienti dall’Europa centrale e orientale. Il fallimento di questo tentativo fu una delle cause della carestia che colpì Napoli. L’autore, dal punto di vista di Trieste, ricostruisce le vicende di tale tentativo, cercando di far emergere gli interessi in campo, gli attori che ne furono protagonisti e le pratiche e le strategie da essi attuate. In tal modo la carestia diventa una “finestra eccezionale” che da un lato consente la narrazione degli eventi “in sé”, dall’altro permette di indagare sui meccanismi del mercato dei cereali e sulle relazioni esistenti tra il mondo del commercio e della finanza, quello dello stato e della burocrazia, quello dell’aristocrazia, quello della produzione, quello dell’applicazione e della creazione delle norme e quello dell’elusione e trasgressione.
In 1763 and 1764, in the approach of the feared food crisis that lay ahead, the Kingdom of Naples turned to Trieste as a way to obtain cereals from Central and Eastern Europe. The failure of this attempt was one of the causes of the famine that struck Naples. From the point of view of Trieste, the author reconstructs the events of this attempt, trying to bring out the different interests confronting each other, the actors who were the protagonists and the practices and strategies implemented by them. In this way the famine becomes an "exceptional window". On the one hand it allows the analysis of the specific events. On the other it allows us to investigate the mechanisms of the cereals market and the relationships between the world of commerce and finance, that of the state and of the bureaucracy, that of the aristocracy, that of production, that of the application and creation of norms, and that of circumvention and transgression
Fragility and glass transition temperature in the rheological response of azobenzene copolymers
No full textTwo copolymers containing nonmesogenic methyl methacrylate (MMA) and nematogenic azobenzene methacrylate (MA4) side groups (30/70 and 40/60 copolymers) azobenzene were studied in the linear viscoelastic regime. The time-temperature superposition principle was found to hold over the whole investigated temperature range, even across the nematic-isotropic transition in the 30/70 copolymer. Rheological steady state and oscillatory measurements were used to obtain the temperature dependence of the zero shear viscosity. The strength and dynamic fragility of these two copolymers were compared with those of the corresponding PMA4 and PMMA homopolymers, which pointed out the role of the structure of the main chain in dictating the relaxational dynamics
Structural and spectroscopic characterization of a suite of fibrous amphiboles with high environmental and health relevance from Biancavilla (Sicily, Italy)
No full textThis study reports new spectroscopic and structural data of fibrous amphiboles from the volcanic area of Biancavilla (Sicily, Italy) that generated interest because of an anomalous increase of pleural mesothelioma of inhabitants. Each of the four samples is made of loose fibers, which show an edenite-winchite (fluorine) compositional trend, with significant tremolite component. Small amounts of iron (3.6-6.0 wt% FeO(tot)) were identified in all samples, and the Fe(3+)/Fe(tot) ratios were evaluated by Mossbauer spectroscopy: two samples are characterized by Fe(3+)/Fe(tot) ratios between 50 and 70%, and the other two have Fe(3+)/Fe(tot) ratios higher than 90%. The OH-stretching region was investigated by FTIR, and no absorption bands were observed. Structural investigation was carried out by X-ray powder diffraction using the Rietveld method. Cell parameters, positional parameters for all the atoms, and site scattering for M1, M2, M3, M4, A, and A(m) were refined. The most important differences with respect to prismatic fluoro-edenite are the decrease of beta, a, and c with decreasing Ca content, A-site occupancy, and tetrahedral Al content, respectively. By combining chemical, spectroscopic, and structural data, possible site occupancies were obtained. In particular, it was found that Fe(2+) is distributed between M1 and M2 sites; moreover, for the two samples enriched in Fe(2+), it is also present at M4. Fe(3+) is generally ordered at M2 site; however, for the two samples enriched in Fe(3+), minor amounts are partially disordered between M1 and M3 sites. For the Biancavilla amphibole fibers, the large compositional variation observed in every sample makes the classification very difficult, so that the regulatory agencies would not classify as "asbestos" the whole mineral series, because of the large components of edenite and winchite in addition to tremolite. Many common features were found with respect to amphibole fibers from Libby, Montana, including Fe contents and oxidation state. Preliminary results of in vitro toxicological tests on Biancavilla fibers confirmed their high reactivity, and suggest that the samples with the highest Fe(2+) contents induce a rapid start to cell mortality
Crystal chemistry of the new asbestiform fluoro-edenite amphiboles of volcanic origin from Biancavilla (Sicily, Italy).
No full textStructural and chemical contrasts between prismatic and fibrous fluoro-edenite from Biancavilla, Sicily, Italy
No full textFluoro-edenite [NaCa2Mg5(Si7Al)O22F2], a new end-member of the calcic amphibole group, is present with both prismatic and fibrous morphologies in the altered volcanic products of the Monte Calvario locality, Biancavilla, on the flanks of Mount Etna, Sicily, Italy. Whereas the crystal chemistry of the prismatic variety was described recently, the fibrous variety has not been well characterized. We report original crystal-chemical and structural data on this fibrous amphibole. Because of the difficulty in analyzing this micrometric material, specific procedures of sample preparation were developed. SEM-EDS microanalyses and Mossbauer spectroscopy indicate a variable composition of the fibers, ranging mostly from fluoro-edenite to, subordinately, winchite, tremolite, and richterite compositions. Given the impossibility of using a single-crystal X-ray method, the powder-diffraction data were evaluated by the Rietveld method. By combining the microchemical data, Mossbauer Fe3+/Fe-tot, values, and with a refinement of the structure, the following chemical formula was obtained from an averaged composition of all the fibrous amphibole analyzed: (Na0.307K0.157)Sigma(0.464) (Ca1.505Na0.495)(Sigma 2.000) ((Al0.104Fe3+)-Al-VI Fe-0.333(2+) 0.162Mg4.255Ti0.062Mn0.063)(Sigma 4.980) ((Si7.520Al0.480)Sigma 8.000)-Al-IV O-22 (F1.970Cl0.020)(Sigma 1.990). The cell parameters, positional parameters for all the atoms, and site scattering for O3, M1, M2, M3, M4, A, and A(m) were refined. In agreement with the site occupancies of cations based on both XRPD and Mossbauer data, Fell was assigned to the M2 and M3 sites, and all Fe3+ was assigned to the M2 site. In particular, Fell content of each M2 site is far greater (0.125 apfu) than that of M3 (0.037 apfu). The analytical procedures utilized here can be adopted for all types of mineral fibers, whether they belong to the asbestiform group of amphiboles or not. In addition to their mineralogical interest, these results are also relevant for environmental and health aspects. The interactions between mineral fiber and the biological environment are strongly related to the crystal chemistry of the fibrous materials
Multi-analytical approach to crystal-chemical characterization of the fibrous fluoro-edenite amphibole from Biancavilla, Sicily, Italy.
No full text
Quantitative chemistry and compositional variability of fluorine fibrous amphiboles from Biancavilla (Sicily, Italy)
No full textCompositional variability of the new fluorine fibrous amphiboles (fluoro-edenite) from the volcanic area of Biancavilla (Sicily, Italy) is reported here for the first time. Quantitative chemical analysis of a suite of four samples was performed by a standardized SEM-EDS microanalysis method, previously developed and tested on different typologies of fibrous amphiboles. The results highlighted compositional differences, especially concerning Si, Ca, Fe, and Na contents, both within the same and among the different samples. Compared to the previously investigated fluoro-edenite prismatic variety, the fluorine fibrous amphiboles showed average values of Si and Fe contents always higher, whereas Ca was significantly lower, which we consider a distinctive character for the fluorine fibrous variety. The Fe(3+)/Fe(tot) ratios, evaluated by Mossbauer spectroscopy, reflected different iron oxidation states: Fe(3+) was always more prevalent than Fe(2+), which was very low for two of the four samples analyzed. Employing the Leake classification, all the analyzed fluorine amphibole fibers showed an edenite-winchite trend, with a non negligible content of tremolite component. Both the fluorine amphibole fibers and the prismatic fluoro-edenite from Biancavilla may be correlated with the same genetic process, but the compositional variability reflect different growth conditions. The large variation observed for Fe(3+)/Fe(tot) ratios in the amphibole fibers is probably due to local variations of oxygen fugacity during crystallization. A workable hypothesis is that a hot metasomatizing fluid, enriched in fluorine and other incompatible elements, altered the volcanic rocks and caused the crystallization of either the fibrous fluorine amphiboles, by a very fast cooling, or the prismatic fluoro-edenite, by slow cooling
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