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Pyrolysis is a promising biomass upgrading process for the production of solid, liquid and gaseous fuels. One of the major concerns about biomass utilization is the remarkable variety of its composition in terms of both organic and inorganic matrices, affecting the pyrolysis characteristic temperatures and products yield. The effect of different alkali and earth alkali metals (AAEMs) on biomass and cellulose pyrolysis has been extensively studied, whereas only few works exist concerning the effect of AAEMs on the pyrolysis of the other two main biomass components, namely hemicellulose and lignin. Hemicellulose, which has a carbohydrate nature like cellulose, is expected to be influenced by the presence of AAEMs during the pyrolysis process. Inthis study, the impact of potassium ions (K+) on the slow pyrolysis of hemicellulose is assessed using xylan asa representative of hardwood hemicellulose. To this aim, slow pyrolysis tests, up to a temperature of 973 K using a heating rate of 7 K/min, were conducted for xylan samples loaded with K+ in different amounts. Commercial xylan was demineralized through a cation exchange resin to reduce the presence of inherentinorganics. Subsequently, the demineralized sample was doped with a controlled amount of K+ (0.3, 0.6 and1.2 wt.%). The experimental results show that doped and demineralized xylan samples exhibit different pyrolytic behaviors. The initial decomposition temperature of the doped xylan is slightly anticipated with respect to that of the demineralized xylan. Moreover, the gas production is favored at the expense of pyrolysisliquids and the evolution of the release rate of permanent gases (mainly CO2 and CO) with the temperature is significantly affected by the presence of K+.

L'Unità di Geofisica dell'Istituto per l'Ambiente Marino Costiero del CNR, sede di Napoli, in seguito alla collaborazione con l'Istituto di Geologia Ambientale e Geoingegneria (IGAG) avente per oggetto la Microzonazione Sismica dei Fori Imperiali e del Colle Palatino in Roma, ha effettuato un serie di indagini sismiche sia in foro (Down-Hole e Cross-Hole) che in superficie (MASW e Tomografia sismica a rifrazione) con l'obiettivo di caratterizzare dal punto di vista dinamico i litotipi rappresentativi dell'area archeologica in esame. A partire dal mese di settembre del 2010 e fino alla fine del mese di gennaio del 2011, l'Unità di Geofisica ha acquisito e contemporaneamente elaborato i dati di campagna fornendo i risultati ottenuti al coordinatore di progetto.

Soot represents one of the most important pollutants in the exhaust gases emitted from combustion processes. The combustion conditions determine to a large extent soot micro- and nanostructure (i.e. primary particle dimension, length and arrangement of the graphene layers) and soot surface chemistry (i.e. number and typology of functional groups). Soot chemicophysical features have a direct influence on its reactivity towards the combustion gases [1]. One of the most meaningful parameters that have a direct influence on the soot reactivity is the oxygenation degree. In this work soot surrogates of uniform size bearing different kind of oxygenated functionalities have been produced through wet oxidations of a commercial carbon black (CB). The selected CB presents morphological and chemico-physical characteristics close to soot generated in combustion environments (flames [2], engines). CB microstructure consists of chain-like aggregates of spherical primary particles with an average diameter in the range of 15-20 nm. The CB organization at a nanoscale level is typical of a disordered carbon exhibiting a concentric organization of the stacked graphitic layers throughout each primary particle, in the better organized areas. Two different oxidation strategies were performed in order to vary the typologies of oxygenated functionalities introduced. Nitric acid [3] (67 wt.%, at 100 °C) and a mixture of concentrated sulphuric acid/hydrogen peroxide in ratio 70:30 v/v (piranha mixture) in accordance with the procedure reported for carbon nanotubes (CNT) [4] were used. The reaction time ranged from 4 to 24 hours with the aim to modulate the number of oxygenated functionalities. The CB-derived soot were gathered in two groups according with the oxidation procedure adopted (nitric acid: SN, piranha mixture: SP) and with the reaction time (SN4, SN15, SN24, SP4, SP15, SP24). Following purification, the soot surrogates were fully characterized by applying a large array of analytical techniques (TEM microscopy, infrared and UV-Visible spectroscopy, thermogravimetry, BET specific surface area, elemental analysis, dynamic light scattering). The evaluation of surface acid site content has been performed by a fluorimetric test with thionine acetate.

Mass spectrometry has currently achieved a mass resolution capable of discerning chemical composition and structure in complex mixtures, especially when applied in combination with chromatographic separation. However, direct mass spectrometric analysis is often carried out for mixtures of high molecular weight species where the degradability and low volatility hinders a reliable chromatographic separation. Whatever is the mass spectrometric system used, complex mixtures produce spectra with a huge number of peaks which generally make difficult the data analysis. In the case of organic mixtures derived from fuel treatment, material production processes or from pyrolytic/combustion processes, repetitive periodicities that are signatures of their composition, origin and formation mechanism cannot be individuated at first glance. This motivates the application of mathematical methods, capable of rapid and repeatable processing of mass spectral data that give repeated spacing patterns throughout the entire mass range. In the present work, Fast Fourier Transform (FFT) and Autocorrelation Function (AF) analysis have been applied to mass spectra of complex PAH-laden samples from combustion systems and/or from heavy fossil fuels in order to individuate periodicities that can indicate preferential growth routes and/or fragmentation patterns related to the chemical composition. It has been shown that the application of these methods does not require a specific software created "ad hoc", but a commercial graphic software can be used offering a higher flexibility in the parameters choice for data analysis. The potentiality of the simultaneous application of both FFT and AF for spectra interpretation has been firstly tested on mass spectra of standard materials like polystyrenes of different masses and standard PAH mixtures. After then, FFT and AF have been applied to other samples of higher complexity and practical use as anthracene oil, naphthalene oil, pitches, combustion-formed tar and carbon particulates. The effects of peak density and resolution on the two different mathematical methods have been shown revealing that FFT is suitable for higher dense and lesser resolved mass spectra whereas AF is more accurate in the determination of the main periodicity when the spectrum presents few peaks and higher resolution. It has been shown that the application of FFT and AF methods of aromatic- laden mixtures relevant in fuel-treatment and combustion can be useful to give an overall view of their composition in relation to the growth routes from which they originate.

Mass spectrometry has currently achieved a mass resolution capable of discerning chemical composition and structure in complex mixtures, especially when applied in combination with chromatographic separation. However, whatever is the mass spectrometric system used, complex mixtures produce spectra with a huge number of peaks which generally make difficult the data analysis. Applications of mathematical methods, capable of rapid and repeatable processing of mass spectral data are emerging. The present work suggests the use of a mathematical approach "editable" from the users and simple to use (Origin 8.0, a commercial graphic software has been used) to have information on correlation and gaps in peak sequences of mass spectra. In the present work, Fast Fourier Transform (FFT) and Autocorrelation Function (AF) analyses have been firstly tested on mass spectra of standard materials like polystyrenes of different masses, standard PAH mixtures, water clusters. After then, FFT and AF have been applied to other samples of higher complexity and practical use as anthracene oil, naphthalene pitche, combustion-formed samples in order to individuate periodicities that can indicate preferential growth routes and/or fragmentation patterns related to the chemical composition.

Utilizando material espectroscópico de 16.9 Å/mm de dispersión, se determinan los parámetros atmosféricos y abundancias químicas de la estrella CP HD 161698, perteneciente al cúmulo abierto IC 4665, clasificada por Abt y Levato (1975), como un objeto del tipo Hg-Mn. Se utiliza la identificación de las líneas espectrales realizada por Malaroda y Levato (1978), quienes además estimaron las abundancias a partir de la construcción de una curva de crecimiento. Este nuevo análisis se realiza usando el programa ATLAS 6, para el cálculo de modelos de atmósferas, que incluye el "blanketing" de numerosas líneas espectrales, el programa BALMER 6, para el cálculo de los perfiles de las líneas del H y el programa WIDTH 6 para la determinación de las abundancias., Asociación Argentina de Astronomía

An abundance analysis of the Si-Mg star HD 3473 is performed with a fully line-blanketed model atmosphere. The adopted atmospheric parameters are Teff = 12000 K and log g = 3.7. This value of Teff is higher by about 2000 K than that used in a previous investigation by Naftilian. Helium is found to be extremely deficient, Si and Mg are overabundant by factors 20 and 50 respectively. Sc, Ti, Mn, Fe, Ni, Sr, Y, Zr and Rare Earths are overabundants too., Asociación Argentina de Astronomía

Se estudia el espectro de la estrella HD 3473 y se identifican los elementos químicos presentes en dos placas Coudé de 16.9 Å/mm de dispersión. Se encuentra Fe en los tres estados de ionización, Si II y Mg II con anómala sobreabundancia, como así también se identifican satisfactoriamente N II, O II, Si III, Cl II, Ca II, Sc II, Ti II, Cr II, Mn II, Ni II, Sr II, Zr II y algunas tierras raras. Se comparan los resultados con los de algunas estrellas B normales y otros objetos anómalos., Asociación Argentina de Astronomía

Studio di fattibilità a Guardia Lombardi: questo studio descrive la valutazione geotermica effettuata nel sito di Guardia Lombardi e la proposta tecnico-economica per lo sviluppo di un progetto impiantistico relativo a risorse geotermiche a media entalpia per la produzione di energia elettrica nel comune di Guardia Lombardi. L'area in esame era già nota da un punto di vista geotermico, poiché mostra un alto flusso di calore individuato dai pozzi per idrocarburi presenti nella regione. La verifica della possibilità di utilizzo della risorsa per la realizzazione dell'impianto e la valutazione della sua realizzabilità, è avvenuta mediante indagini geologiche, idrogeologiche, geochimiche, geofisiche e la realizzazione di una specifica simulazione numerica dinamica dei parametri fisico-chimici del serbatoio, utilizzando i dati forniti dai pozzi per idrocarburi. Questa analisi ha portato alla definizione di una zona potenzialmente utile alla produzione di energia, ubicata in corrispondenza della culminazione strutturale perforata da un pozzo profondo Bonito 1 Dir. sulle quale si è innestato il lavoro di analisi termodinamica, tecnologica ed economica atto a definire la realizzabilità di un sistema di produzione di energia termica, meccanica e quindi elettrica. La simulazione numerica del comportamento del serbatoio geotermico nel settore del pozzo Bonito 1 Dir ha messo in evidenza un potenziale massimo di estrazione sostenibile per almeno 20 anni di 13.5 kg/s, nel caso di pozzo singolo, e di un intervallo di portate comprese tra 10 e 60 kg/s, sostenibili per 25 anni, nel caso di estrazione con reiniezione. Conseguentemente alla scelta del sito di estrazione è stata analizzata la tecnologia più appropriata alla valorizzazione della risorsa geotermica, prendendo in considerazione diverse tecnologie selezionate mediante un'attenta ricerca bibliografica, poste a confronto. Sulla base di considerazioni tecniche, economiche ed ambientali, la scenario preso a riferimento prevede la realizzazione di un doppietto geotermico ovvero di due pozzi profondi per estrazione e reiniezione di fluidi idrotermali.