Search results for "Processi"
showing 10 items of 9638 documents
Principal component analysis and cluster analysis for measuring the local organisation of human atrial fibrillation
2001
The distribution of atrial electrogram types has been proposed to characterise human atrial fibrillation. The aim of this study was to provide computer procedures for evaluating the local organisation of intracardiac recordings during AF as an alternative to off-line manual classification. Principal components analysis (PCA) reduced the data set to a few representative activations, and cluster analysis (CA) measured the average dissimilarity between consecutive activations of an intracardiac signal. The data set consisted of 106 bipolar signals recorded on 11 patients during electrophysiological studies for catheter ablation. Performances of PCA and CA in distinguishing between organised (t…
The Role of the Amygdala in the Extinction of Conditioned Fear
2006
The amygdala has long been known to play a central role in the acquisition and expression of fear. More recently, convergent evidence has implicated the amygdala in the extinction of fear as well. In rodents, some of this evidence comes from the infusion of drugs directly into the amygdala and, in particular, into the basolateral complex of the amygdala, during or after extinction learning. In vivo electrophysiology has identified cellular correlates of extinction learning and memory in the lateral nucleus of that structure. Human imaging experiments also indicate that amygdaloid activity correlates with extinction training. In addition, some studies have directly identified changes in mole…
ION EXCHANGE MEMBRANE CRYSTALLIZER FOR MAGNESIUM RECOVERY FROM SEAWATER AND INDUSTRIAL BRINE
2020
The treatment and valorisation of waste brines deriving from industrial processes raised in the last years a strong interest in order to promote the whole process sustainability both in terms of minimisation of environmental impacts and raw materials recovery within a circular economy approach. With this respect, magnesium recovery from brines can be an interesting and practical example. In this work, a novel ion exchange membrane crystallizer (CrIEM1) is presented. In a CrIEM reactor, the presence of an Anion Exchange Membrane, separating a brine and an alkaline solutions, allows the passage of hydroxyl ions from the alkaline to the brine compartment, where crystallization of magnesium hyd…
AN INTEGRATED APPROACH FOR THE HCl AND METALS RECOVERY FROM WASTE PICKLING SOLUTIONS: PILOT PLANT DESIGN AND OPERATIONS
2020
Pickling is one of the key steps in the hot-dip galvanizing process, where HCl solutions are largely used to remove metal oxides from metallic surfaces, thus generating spent waste liquors containing high concentrations of metals and acid. Disposal of the industrial pickling waste dramatically affects the hot-dip galvanizing industry economics and environmental footprint. Thus, reducing strong acid waste disposal is one of the most beneficial steps to enhance the process sustainability. Moreover, the continuous regeneration of pickling solutions enhances pickling rate and process performance, also minimizing industrial wastewater disposal and chemicals consumption promoting the circular use…
DEVELOPMENT AND MODELING OF MEMBRANE PROCESSES FOR THE REGENERATION OF ACID PICKLING SOLUTIONS
2021
The doctoral thesis focuses on a novel integrated process for the recovery and valorisation of acid and metal salts present in the waste solutions of the pickling process. The proposed process is based on the integration of two innovative membrane technologies, the Diffusion Dialysis and the Membrane Distillation, coupled with a reactive precipitation section. This hybrid process allows the recovery and the enhancement of waste solutions, as well as optimal operating conditions for the continuous pickling process, thus improving its efficiency. Hydrochloric acid recovery was assessed through a detailed study on the Diffusion Dialysis process by implementing a wide experimental campaign usin…
La costruzione della memoria pubblica come “performance culturale”: riflessioni a partire dalla commemorazione della strage di Portella della Ginestra
2009
Commemorare, ovvero il ricordare e celebrare in forma pubblica, implica l’evocazione – da parte di attori specifici – di retoriche anche in forma solenne, di fronte ad un pubblico, o più verosimilmente a pubblici diversi: il ricordare medesimo ha il significato, tutto sociale, di riattualizzare la memoria del gruppo sociale di appartenenza, spesso ritualizzandola.Un’analisi sociologica che non si limiti, “[...] a indagare le condizioni istituzionali ed esteriori, ambientali, della produzione culturale, ma che si introduca, passando dalla porta principale, nello stesso oggetto o prodotto culturale, per rivelarne la struttura anche semiotica e narrativa, a decifrarne il codice” (Santoro, 2006…
Processi erosivi e messa in sicurezza del territorio siciliano
2010
Terahertz polarization-division multiplexing within a four-wire waveguide
2022
We demonstrate a new metal-wire waveguide topology, namely a four-wire waveguide, which simultaneously acts as a broadband terahertz polarization-division multiplexer and as a novel platform to realize the independent manipulation of polarization-division multiplexed terahertz signals.
Cavezzo, the first Italian meteorite recovered by the PRISMA fireball network. Orbit, trajectory, and strewn-field
2020
ABSTRACT Two meteorite pieces have been recovered in Italy, near the town of Cavezzo (Modena), on 2020 January 4th. The associated fireball was observed on the evening of New Year’s Day 2020 by eight all-sky cameras of the PRISMA fireball network, a partner of FRIPON. The computed trajectory had an inclination angle of approximately 68° and a velocity at infinity of 12.8 km s−1. Together with the relatively low terminal height, estimated as 21.5 km, those values were indicating the significant possibility of a meteorite dropping event, as additionally confirmed by the non-zero residual total mass. The strewn-field was computed taking into account the presence of two bright light flashes, re…
Identità e meticciato. Una relazione problematica
2015
L'articolo presenta una riflessione sul concetto di identità, mostrando i rischi di essenzializzazione e reificazione e mettendone in luce gli aspetti relazionali e situazionali.