1,882 research outputs found
Le borgate di Palermo
Lo scritto si riferisce a un lavoro svolto sulle borgate palermitane a partire dall'applicazione dell'analisi morfologica, sulla scorta dell'esperienza del Piano Programma sul centro storico
I quartieri ad Algeri e a Parigi di Fernand Pouillon architetto mediterraneo
L'articolo tratta dei quartieri negli anni '50 ad Algeri e a Parigi di Fernand Pouillon: un architetto ignorato dalla critica per molto tempo in quanto fuori dal clich\ue9 della modernit\ue0, avendo costruito molto con uso della pietra, composizione simmetrica, ricerca della monumentalit\ue0. Pu\uf2 essere riconosciuto come emblematico rappresentante della mediterraneit\ue0
Calorimetric Study Of Intercalation Of N-alkyldiamines Into α-titanium Hydrogenphosphate
A series of n-alkyldiamines of general formula H2N(CH2)nNH2 (n = 2-9) has been intercalated into the crystalline lamellar compound α-Ti(HPO4)2·H2O (TiP) from aqueous solution. The amount intercalated was followed batchwise at 298 ± 1 K and the variation of the original interlayer distance for TiP (756 pm) was followed by X-ray powder diffraction. Linear correlations with good fits were obtained for the interlamellar distance (d) or for the number of moles intercalated (nint) as a function of the number of carbon atoms in the aliphatic chain (nc): d =(883.14 ± 12.76) + (108.51 ± 2.20)nc and nint =(5.79 ± 0.12) - (0.28 ± 0.02)nc. The exothermic enthalpies for the intercalation are related to the monomolecular layer arrangement with a longitudinal axis inclined by 58° to the inorganic sheets. The enthalpies for the overall reaction 2O3P-OH(c) + H2N(CH2)nNH2(c, l) = O3P - O-+H3N(CH2)nNH3+-O - PO3(c); ΔintH, determined by reaction-solution calorimetry at 298.15 ± 0.02 K are correlated with the number of carbons in the aliphatic chain or the interlamellar distance, by the equations Δint H= -(56.16 ± 0.67)-(2.06 ± 0.12)nC and ΔintH = -(39.41 ± 1.41)-(1.80 × 10-2 ± 0.10 × 10-2)d. The enthalpic value for nc = 0 gave -56.17 ± 0.67 kJ mol-1 which corresponds to the intercalation of two moles of ammonium cation.61219631966Alberti, G., Galli, P.C., Costantino, U., Torracca, E., (1967) J. Inorg. Nucl. Chem., 29, p. 571Clearfield, A., (1982) Inorganic Ion Exchange Materials, , CRC Press, Boca Raton, FLSuárez, M., Garcia, J.R., Rodriguez, J., (1984) J. Phys. Chem., 88, p. 159Alberti, G., Casciola, M., Costantino, U., (1985) J. Colloid Interface Sci., 107, p. 25
La piazza "mediterranea" nei borghi rurali in Sicilia
L'articolo tratta dei borghi rurali costruiti in Sicilia alla fine degli anni '30 e subito dopo la guerra, e del ruolo della piazza in quanto carattere di mediterraneit\ue0 dei compless
La ricerca sui centri storici. Giuseppe SamonĂ e il Piano Programma per Palermo
Il volume tratta di vari aspetti del Piano Programma, ancora attuali a 30 anni di distanza e malgrado la mancanza di attuazione
Bayesian stochastic blockmodeling
This chapter provides a self-contained introduction to the use of Bayesian
inference to extract large-scale modular structures from network data, based on
the stochastic blockmodel (SBM), as well as its degree-corrected and
overlapping generalizations. We focus on nonparametric formulations that allow
their inference in a manner that prevents overfitting, and enables model
selection. We discuss aspects of the choice of priors, in particular how to
avoid underfitting via increased Bayesian hierarchies, and we contrast the task
of sampling network partitions from the posterior distribution with finding the
single point estimate that maximizes it, while describing efficient algorithms
to perform either one. We also show how inferring the SBM can be used to
predict missing and spurious links, and shed light on the fundamental
limitations of the detectability of modular structures in networks.Comment: 44 pages, 16 figures. Code is freely available as part of graph-tool
at https://graph-tool.skewed.de . See also the HOWTO at
https://graph-tool.skewed.de/static/doc/demos/inference/inference.htm
Different neutral surfactant template extraction routes for synthetic hexagonal mesoporous silicas
The co-condensation of a tetraethoxysilane molecule on a neutral n-octylamine surfactant template is a convenient synthetic methodology for mesostructured material preparations. Distinct routes of template removal were investigated. The neutral surfactant was removed by calcination, hot solvent extraction, heating at 150 degreesC, in vacuo at room temperature and at 100 degreesC, and air drying, with the products assigned as HMM, HMS, HME, HMV1, HMV2 and HM, respectively. Si-29 NMR, infrared, surface area, pore diameters and pore volume determinations were employed to characterize each sample. Elemental analysis detected the presence of amine residues of 1.8, 1.2, 0.2, 1.6 and 0.30 mmol g(-1) for HMA, HME, HMS, HMV1 and HMV2, respectively. The HMM, HMS and HMV2 samples presented a low amount of amine residues, and HMS and HMV2 have the great advantage of permitting template removal without calcination.12123823382
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