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Modelling entrained-flow slagging gasification of solid fuels with near-wall particle segregation
No full textof the model is a comprehensive “particle segregation” submodel, based on the near-wall phenomena associated
with bulk-to-wall particle transfer. Ash deposition onto the reactor walls, adhesion and inelastic rebound of char
particles upon collision with the wall, confinement and dissipation of kinetic energy in the near-wall region
promote the formation of a dense-dispersed particle phase where an extended inventory of char particles accumulates.
The fate of char particles is analyzed by considering migration toward the wall, interaction with the
dry or the slag-covered wall, deposition onto the slag layer, accumulation in the near-wall region and heterogeneous
gasification reactions. The core of the model consists of mass balance equations on solids and gases in
lean (bulk), dense (near-wall) and slag phases. The constitutive equations and parameters of the particle-wall
interaction submodel were partly determined by validation against experimental results, partly treated as model
parameters.
Although the model cannot be used as a predictive tool at its present stage, due to the uncertainties associated
with the determination of the model parameters, it provides a powerful tool to assess the relevance of particle
segregation to the gasifier performance and to point at the research priorities that could improve its predictive
ability. Application of the model is demonstrated with reference to a downdraft entrained-flow slagging gasifier.
Model results are discussed in terms of partitioning of char/ash particles among lean, dense and slag phases,
carbon gasification degree, syngas composition and lower heating value. A sensitivity analysis with reference to
selected model parameters is carried out to evaluate their relevance to the gasifier performance prediction
On the lateral capacity of reinforced masonry members using combined retrofitting methods
No full textHistoric walls were designed in the past to withstand vertical compressive loads. However, during seismic events, walls withstand lateral loads and their response is usually unsatisfactory. Reinforcement is often needed and several retrofitting methods have been proposed in the last decades. This paper analyses and compares the strength results of several experimental campaigns, recently carried out by the authors, with the specifications and mechanical properties suggested by the new (2018) Italian Seismic Code. Two retrofitting methods are considered: grout injections, alone, and in combination with jacketing. The effect of combined retrofitting methods was also investigated in this paper with the aim at studying the limitations of the actual Italian Building Code for interventions on listed buildings. Shear tests were carried out on-site and the effectiveness of the two retrofitting methods was discussed
Cumulative damage to school buildings following the 2016 central Italy earthquake sequence
No full textThe 2016 central Italy earthquake highlighted the cumulative effects of a seismic sequence on the damage to buildings. In particular, the paper focuses on the behaviour of school buildings struck by several earthquakes in the seismic sequence. An initial analysis involves the correlation between the main ground motion parameters and the seismic behaviour of school buildings. The correlation between ground motion parameters and usability rating of school buildings, collected by means of the AeDES survey form, is also discussed. The analysis showed that several school buildings, usable after the first shock on 24 August 2016, resulted unusable at the end of the seismic sequence due to the extensive structural or non-structural damage. The effects of the seismic sequence are herein discussed, taking into account the school buildings’ date of construction and relevant design methods, structural types (i.e. RC and masonry), and peak ground acceleration experienced in the sequence. Finally, relationships between damage and actual repair costs are used to observe the incidence of the damage provided by the seismic sequence in terms of economic losses
Low Dose Bisphenol-A Regulates Inflammatory Cytokines through GPR30 in Mammary Adipose Cells
No full textThe dramatic rise in obesity and metabolic syndrome can be related, at least in part, to environmental chemical factors such as Bisphenol-A (BPA). In this study, we aimed to understand the effects of low-dose Bisphenol-A on the human mature adipocytes and stromal vascular fraction (SVF) cells, obtained from subcutaneous mammary adipose tissue of overweight female patients, undergoing surgical mammary reduction. 24 and/or 48 hours exposure to BPA 0.1 nM elicited significant increase of the inflammatory molecules interleukin-6 (IL-6), interleukin-8 (IL-8), Monocyte chemo-attractant protein 1α (MCP1α) and induced G protein-coupled estrogen receptor 30 (GPR30) levels more than 2-fold both in mature adipocytes and SVF cells. These effects were similar to that obtained in presence of GPR30-specific agonist G1 (100 nM) and were reverted by G15 (1 μM), a GPR30-selective antagonist. As a result of BPA-GPR30 signaling activation, Fatty Acid Synthase (FAS) and leptin mRNA levels were significantly higher upon BPA exposure (p<0.05) in mature adipocytes, with an opposite effect on adiponectin (ADIPOQ). In addition, an increase in SVF cell proliferation and ERK1/2 phosphorylation, was observed, compared to untreated cells. G15 reverted all of these effects. Interestingly, the action of BPA on SVF cell growth was mimicked by IL-8 treatment and was reverted by incubation with anti-IL8 antibodies. All these data suggest that BPA at 0.1nM, a 10 times lower concentration than environmental exposure, increases the expression of pro-inflammatory cytokines via GPR30 both in mature mammary adipocytes and in SVF cells with a possible involvement of IL-8
Unamuno inédito: La educación por hipnotismo
No full textIl contributo riscatta un articolo ancora inedito di Miguel de Unamuno, conservato nella Casa Museo Unamuno di Salamanca e intitolato La educación por hipnotismo. Il testo è preceduto da uno studio introduttivo in cui il documento viene datato e collocato all’interno della produzione unamuniana, con particolare riferimento alle questioni pedagogiche
Il fondamento costituzionale del diritto inglese
No full textUn'indagine sul fondamento costituzionale del diritto inglese, dalla Magna Carta alle recenti posizioni della Corte Suprema in materia di Brexi
Las finanzas públicas en la era de la crisis: herramientas, soluciones e intentos de reforma. El caso del Reino de Nápoles en el siglos XVII y XVIII.
No full text¿Las crisis financieras también pueden considerarse un motor de innovación? ¿Las prácticas de gestión, las nuevas reglas de operación, modernización y racionalización del sistema pueden originarse por las crisis de las finanzas? • Las formaciones corporativas, sociales y territoriales siempre han sido vistas por la historiografía tradicional cerrada en un papel de defensa, resistencia, oposición a las iniciativas de reforma. ¿Se deben considerar realmente solo de acuerdo con esta clave interpretativa? Integración e interdependencia entre el aparato central y las élites sociales son términos en los que la historiografía ha llamado la atención (Russel Major 1980, Waquet 1980, Fasano Guarini 1983, Waquet y Menjot 1995). ¿Hasta qué punto son las instituciones financieras y económicas el producto de las relaciones políticas entre la corona, los grupos de influencia y el parlamento
