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A total of 35 honey samples from different regions of Algeria were studied to determine their phenolic profiles. Phenolic compounds, products of the secondary metabolism of plants, were extracted with amberlite XAD-4 and analysed by liquid chromatography, with diode array detection and electrospray ionisation mass spectrometry in negative ion polarity. By using colorometric assays, Erica honeys showed the highest content of phenolic compounds and flavonoids (245 ± 54 mg GAE/100 g and 29 ± 6 mg QE/100 g, respectively). More than 30 compounds were identified in the honey samples studied including 14 phenolic acids and 16 flavonoids. In general, honey samples showed different chromatographic profiles. It has been shown that 4-hydroxybenzoic acid, apigenin, chrysin, galangin, kaempferol, isorhamnetin, luteolin and pinocembrin were present in all honey extracts. Moreover, caffeic, p -coumaric and vanillic acids; abscisic and syringic acids; and benzoic acid were detected in 34, 33 and 32 honey samples, respectively. The members of flavonol subclass were the most abundant of the identified flavonoids. Gallic and homovanillic acids, daidzein and myricetin were less present: 7, 5, 7 and 6 in honey samples, respectively. Caffeic and p -coumaric acids were potential floral markers for Capparis spinosa and Trifoliumn honeys, respectively.

Reafforestation is generally based on the planting of exotic fast growing tree species suitable for adapting to even harsh environments. Once the introduced plants ameliorate soil conditions, they can be progressively replaced by au- tochthonous plant species. Reafforestation is applied worldwide. However, only few studies on the effect of reafforesta- tion on lands from Mediterranean regions are available. This paper reports the characterization by cross polarization 13C NMR spectroscopy of fresh leaves and superficial litters from a reafforestated area in central Sicily (Italy). NMR assign- ment is attempted. A differentiation among the molecular systems within leaves and litters is also done on the basis of NMR assessment. Results showed that the main differences among the leaves of four forest trees (two eucalyptus spp., one cypress sp. and one pine sp.) occur in the distribution of the aromatic and alkyl carbons. In particular, the alkyl moie- ties in the eucalyptus spp. leaves were attributed to branched structures belonging to the eucalyptus oil, whereas linear fatty acids were more representetive in the NMR spectra of pine and cypress leaves. In addition, the aromatic carbons of the conifer leaves were assigned not only to lignin- and tannin-like structures, but also to common olefin carbons in un- saturated fatty acids and abietic acid-like systems. The spectra of the litters resembled, as expected, those of the leaves. However, the presence of very large carbohydrate NMR signals suggested that degradation processes were still ongoing in litters. A comparative evaluation of CPMAS 13C NMR spectra was done by applying principal component analysis. This paper confirmed the suitability of CPMAS 13C NMR spectroscopy in evaluating the differences among natural bio-masses which are the major nutrient sources for soil micro-organisms and the main input for humification processes. Made available in DSpace on 2021-11-02T02:06:55Z (GMT). No. of bitstreams: 1 CPMAS-13C.pdf: 193267 bytes, checksum: 50e56a42c807b654cf822da79e1ffcb2 (MD5) Previous issue date: 2010

Prendendo le mosse da una sommaria presentazione della parabola biografica e scrittoria del perugino Giovan Giacomo Ricci, finora pressoché oscura, si propone una lettura del suo “poema drammatico” Il maritaggio delle Muse, edito ad Orvieto nel 1625. La prospettiva specifica di questa lettura affronta la presenza e la maturazione lirica del personaggio Marino nel Maritaggio, opera non a caso collocabile a cavallo tra il ragguaglio e la commedia. All'interno del sistema poetico e parnasiano del Maritaggio ed evidenziando l'impalcatura citazionale sottesa al dramma, dunque, si segue l'evoluzione scenica del Marino da giovane poeta municipale e d'occasione a maturo interprete dei generi più vari, dall'idillio alla tenzone, fino al poema grande. Starting from a brief presentation of Giovan Giacomo Ricci's biography and bibliography (still now almost unknown), this paper suggests an interpretation of Ricci's “poema drammatico” Il maritaggio delle Muse, published in Orvieto in 1625. This composition, between the comedy and the “ragguaglio di Parnaso”, is read following the presence and the poetic evolution of the character of Giovan Battista Marino. In the poetical and parnasian structure of Maritaggio, this article underlines its quoting architecture. This paper remarks, in Ricci's drama, Marino's growth from a young love and municipal poet to an able interpret of various genres, from the bucolic to the comic one, up to the long poem.

Biochar is defined as charred organic matter applied to soil in a deliberate manner, with the intent to improve soil properties (Lehmann et al., 2009). Biomass-derived char can be used as energy carrier, as adsorber and as material for the improvement of soil properties. Carbonized organic matter can have different physical and chemical properties depending on the technology used for its production. Moreover char texture influences deeply physical and chemical properties. In this work effect of texture on the dynamics of a water saturated biochar was analyzed by FFC NMR. An industrial biochar derived from gasification of poplar wood was sieved to determine influence of texture on water dynamic on particles surface. Sieves with 2, 1 and 0.3 mm have been used to separate three different texture fractions. Each sample has been saturated with water and then analysed by FFC NMR relaxometry by applying a range of magnetic field from 40MHz to 0.01MHz. Three profiles with different longitudinal relaxation rate have been carried out. Sample with texture 1-2mm has a profile with the lowest longitudinal relaxation rate (R1). Profile of sample with textures

Anthropogenic activities alter the natural flow of materials and introduce novel chemicals into the environment thereby causing serious soil and water pollution. Indeed, many industries produce aqueous effluents containing toxic substances, especially heavymetals. The presence of these contaminants in the environment is a great issue because of their toxicityand bioaccumulation ability which affect human life and the environment. Various physicochemical and biological techniques have been used to remove the heavy metals from waste waters, including chemical precipitation, ion exchange, chemical coagulation, electrolytic methods, membrane processes, and adsorption. Biochar is a carbonaceous material obtained from the pyrolysis of plant and animal biomasses. Due to its high porosity, it could be a potential alternative to the existing conventional technologies for the removal and/or recovery of metal ions from aqueous solutions. The aim of this work was the chemical-physical characterization of biochar produced from chicken manure (CM), conifers and poplar wood wastes in order to assess their ability in the removal of heavy metal from aqueous solutions. Chemical-physical characterization of the different CM chars was conducted by cross polarization magic angle spinning (CPMAS) 13 C NMR spectroscopy and NMR relaxometry together with a comparative study between the removal efficiencies of Cu(II), Ni(II) andPb(II) from synthetic wastewater by using adsorption onto biochars surfaces. From adsorption studies, it was observed that conifer biochar did not significantly adsorbed metals. This behavior is probably due to his own chemical characteristics, since it’s quite hydrophobic and probably its surface lacks functional groups able to bind ions. Conversely, chicken manure biochar proved to have the highest removal efficiencies for all the metals considered, in the order Pb(II)>Cu(II)>Ni(II) ions. In conclusion, different chars have different physicochemical characteristics so they should be addressed to different uses. For example, conifer char should not be used for remediation since it’s not effective in removing inorganic metals from aqueous solutions. The most effective in remediation was chicken manure biochar, probably thanks to the presence of nitrogen on its surface. In fact, nitrogen has a free electronic doublet/pair able to interact with cation. Finally, char metals absorption involves both a physical and a chemical mechanism and further studies should be addressed to explain it.

Char or biochar is a type of charcoal obtained from gasification/pyrolysis of biomasses. Instead of burning standing biomass from cleared forest, the resource is charred. The result is a highly porous, carbon-rich solid residue, really similar in appearance to the coal produced by natural burning. First considered an industrial waste, in recent years, the interest in this material has grown enormously given its ability to improve physical, chemical, biological and mechanical properties of soils, when used as amendment. However, its effects are highly variable depending onits chemical-physical properties which in turn depend greatly on the starting feedstock. The present study reports about the effects of different chars obtained from industrial thermo-chemical processes (gasification for energy production) on soil quality. In particular, radish germination was monitored using conifer, poplar and marc biochar as amendment. Results revealed that radish roots had different lengths depending on the nature of biomassesused to produce the different chars. Actually, the char produced from marc completely inhibited seeds germination. Moreover, to investigate the effect of the genotype, a study is going on regarding the influence of different biochars on seed germination of Troyer citrange [Citrus sinensis (L.) Osb. x Poncirus trifoliata (L.) Raf.].High resolution solid state NMR spectroscopy revealed no differences among the chemical nature of the different chars. Conversely, low resolution 1H fast field cycling NMR relaxometry showed that porosity of chars was directly related to the nature of the biomassesused for the thermo-chemical transformations. We can conclude that not all the chars can be applied to soil to improve its quality, thus a careful characterization must be carried out prior to field application in order to avoid counter-effects which can damage soil productivity.

Through archival sources and repertories this paper offers a biographical and bibliographical outline of Giovan Battista Oddoni, born in Varese and employed in Milan, Mantua and Turin from 1618 to 1630. The paper enlightens in particular on his academic and courtesan relations, especially with the Houses of Gonzaga and Visconti Borromeo from Lainate, then, after a forced transfer in Turin due to legal problems, with the House of Savoy. The paper also discusses the history of composition, structures and contents of Idillii (1618), the tragedy Edemondo (1621) and Rime (1623), published in Milan; of them, the paper shows the aspects encoded in the respective genres (with a raid on the history of seventeenth century’s idyll in Lombardy). Finally, the paper discusses the tragicomedy Arione (1628), published and performed in Turin, which is ascribed for the first time to the author (previously limited to the symbol «G.B.O.» that appears in the frontispiece). The paper considers this ‘maritime fable’ for its courtesan, allegorical and didactic purposes, as well as for the reuse of expressive formulas and plot schemas taken from Oddoni’s previous literary experience., Annali Online Lettere - Ferrara, VII 2 (2012)

La lignocellulosa è la più abbondante fonte rinnovabile per la produzione di bioetanolo. Sfortunatamente la produzione di biocarburanti liquidi da scarti lignocellulosici presenta molti inconvenienti a causa della compattezza e della complessità di questi materiali, caratteristiche che rendono molto più difficoltosa la loro degradazione enzimatica in zuccheri fermentabili rispetto ad altri biopolimeri come l’amido. Inoltre il costo della produzione di bioetanolo da biomasse lignocellulosiche è ancora molto alto rispetto a quello dei processi industriali che utilizzano come materiale di partenza l’amido. Obiettivo del presente studio è quello di testare su campioni di biomassa lignocellulosica un metodo di degradazione acida messo a punto sulla cellulosa microcristallina, al fine di ottenere zuccheri fermentabili per la produzione di bioetanolo. La biomassa utilizzata in questo studio è ottenuta dalla potatura di viti. Un’aliquota di biomassa viene posta in acido fosforico e riscaldata a 80°C per un tempo variabile nell’intervallo 15-300 minuti. Il supernatante viene separato ed analizzato mediante analisi colorimetrica per individuare la concentrazione di zuccheri riducenti. Il residuo solido viene prima lavato, poi seccato ed infine analizzato in spettroscopia CPMAS 13C NMR. Il risultato delle indagini colorimetriche ha mostrato che a circa 120 minuti si raggiunge il massimo della concentrazione di zuccheri riducenti. A partire da 150 minuti si osserva la diminuzione della concentrazione di zuccheri dovuta alla degradazione degli stessi come descritto già in Butera et al. (2011). Le analisi in spettroscopia CPMAS 13C NMR hanno messo in evidenza come il trattamento in acido fosforico consenta l’estrazione della cellulosa dalla biomassa solida. Infatti gli spettri NMR della componente solida dopo 60 minuti di trattamento contengono unicamente segnali di lignina. Questi risultati hanno trovato conferma nelle misure di rilassometria FFC NMR condotte sulla biomassa tal quale e sui solidi sottoposti ad idrolisi acida. Dopo trattamento con acido fosforico si osserva una diminuzione del T1(H) seguita da un progressivo aumento. La diminuzione è attribuibile al fatto che si ha depolimerizzazione dovuta all’idrolisi acida della cellulosa e dell’emicellulosa, i principali componenti delle biomasse lignocellulosiche. Man mano che si allontana il residuo polisaccaridico, si ottiene un innalzamento del T1(H) perché si «isola» la lignina altro polimero funzionale del residuo usato per questi esperimenti.

Anthropogenic activities alter the natural flow of materials and introduce novel chemicals into the environment thereby causing serious soil and water pollution Indeed, many industries produce aqueous effluents containing toxic substances, especially heavy metals The presence of these contaminants in the environment is a great issue because of their toxicity and bioaccumulation ability which affect human life and the environment Various physicochemical and biological techniques have been used to remove the heavy metals from waste waters, including chemical precipitation, ion exchange, chemical coagulation, electrolytic methods, membrane processes, and adsorption Biochar is a carbonaceous material obtained from the pyrolysis of plant and animal biomasses Due to its high porosity, it could be effectively used as a remediation tool to retain inorganic contaminants A comparative study between the removal efficiencies of Cu (II) and Ni (II) from synthetic wastewater by using adsorption onto biochars produced from chicken manure, conifers and poplar wood wastes was conducted to assess their ability in the removal of heavy metal from aqueous solutions The results showed that chicken manure biochar proved to have the highest removal efficiencies (up to 90% of removal) for both Cu (II) and Ni (II) ions The sorption ability of chicken manure biochars that underwent various degrees of carbonization (chars formed by pyrolysis at 350 and 500°C) was also investigated Higher pyrolysis temperatures lead to the disappearance of certain surface functional groups (e g , aliphatic) and the formation of others (e g , aromatic) These differences leads to a different adsorption behavior

Anthropogenic activities have produced numerous sites with extensive contamination close to residential areas. Several physicochemical and biological remediation methods exist for remediation of metal contaminated soils and lands, such as soil washing, soil flushing, phytoremediation, and electrokinetics. Biochar (biologically derived charcoal) is produced by pyrolysis of biomasses under low oxygen conditions, and it can be applied for recycling organic waste in soils. The main objectives of the present study were to determine the possible use of biochar from forest ersidues (Populus nigra) in order to achieve a stabilization of inorganic contaminants by adsorption processes. Adsorption of copper by biochar from dilute solutions showed a closer agreement with the Langmuir isotherm in a concentration range 25-500 mM. The decontamination by biochar is very suitable because the treatment is passive and does not require specialized equipment or extensive labor as compared to other remediation methods. Moreover, biochar is also a possible carbon sink due to its long term storage in environment, thereby favouring mitigation of the anthropic impact on environment.

In the last years, phosphoric acid has been increasingly considered as a simple and economic solvent for cellulose pretreatment before its degradation to glucose. Cellulose swells in 71–80% phosphoric acid solutions, whereas at higher H3PO4 concentrations dissolution appears to occur. In addition, it is reported that regenerated cellulose is more easily fermentable to bioethanol. The aim of the present study was to elucidate the mechanism for cellulose regeneration following treatment with phosphoric acid at room temperature. CPMAS 13C NMR spectra revealed a downfield shift of the 13C NMR signals from the regenerated cellulose as compared to the crystalline one. CPMAS 31P NMR spectroscopy showed presence of organic phosphate in the regenerated cellulose. These results suggested that cellulose regeneration consisted in the precipitation of a phosphorylated polymer. Fast field cycling NMR relaxometry confirmed such hypothesis. In fact, the correlation time of water saturated crystalline cellulose was shorter than that measured for the water saturated regenerated cellulose. The phosphate groups bound to the regenerated cellulose surface allow restriction of water mobility, thereby producing longer correlation times. Finally turbidimetric analyses revealed that the mechanism of regeneration consisted in a first reduction of the colloidal cellulose size followed by aggregation, colloidal size increment and flocculation. This study is of paramount importance to understand how phosphoric acid interact with cellulose in order to address its possible uses in biomass transformation for bioenergy purposes.

La pollina è tradizionalmente utilizzata in agricoltura come fertilizzante organico grazie al suo alto contenuto in nutrienti immediatamente disponibili per le piante (principalmente azoto, potassio e fosforo). Nonostante i vantaggi apportati alle colture, l’eccessivo uso della pollina come ammendante del suolo può causare gravi problemi ambientali, tra cui rischi per la salute umana e lisciviazione di nitrati o altri inquinanti nelle acquee sotterranee. Per diminuire i rischi legati al suo utilizzo, una soluzione alternativa potrebbe essere il ri-utilizzo energetico della pollina tramite la sua conversione in biochar. Il biochar è una sostanza carboniosa derivante dalla pirolisi di qualsiasi materiale organico. Grazie alle sue caratteristiche fisico-chimiche (elevata porosità, alto contenuto in carbonio e nutrienti), è risultato essere un ottimo ammendante dei suoli. Infatti ne aumenta la ritenzione idrica, la fertilità e la capacità di scambio cationico. Le proprietà fisico-chimiche del biochar sono però fortemente influenzate dalle condizioni di pirolisi, in particolare dalla temperatura massima raggiunta e dal tempo di residenza. Questo studio si propone di valutare l’influenza della temperatura di pirolisi e del tempo di residenza sulle proprietà fisico-chimiche del biochar prodotto da pollina. In particolare tre biochar sono stati ottenuti a 350°C, 450°C e 600°C. Il tempo di residenza in muffola è stato di 30min e 120min per ogni temperatura. Gli spettri CPMAS 13C NMR hanno mostrato che le caratteristiche chimiche dei biochar sono maggiormente influenzate dalla temperatura piuttosto che dal tempo di pirolisi. Tuttavia, indagini in risonanza magnetica nucleare a basso campo in rilassometria protonica (misure di T2 a campo fisso e T1 a campo variabile) hanno evidenziato che le proprietà superficiali dipendono anche dal tempo di pirolisi oltre che dalla temperatura. Questo studio ha dimostrato che la combinazione di più tecniche NMR (alto e basso campo, campo fisso e campo variabile) consente di riconoscere le differenze tra biochar ottenuti in condizioni differenti. La conoscenza della natura chimico-fisica del biochar in funzione dei processi con cui esso è ottenuto è fondamentale per la comprensione dei possibili usi tecnologici di questo nuovo materiale biosostenibile.

Un campione biossido di titanio sintetizzato in laboratorio è stato ottenuto mediante idrolisi di TiCl4 in acqua deionizzata (rapporto in volume 1:10) a temperatura ambiente. Dopo 12 h di agitazione la soluzione trasparente è stata portata all’ebollizione per 0.5 h per ottenere la sospensione finale. La sospensione è stata quindi seccata alla temperatura di 50°C per ottenere il catalizzatore in polvere. Successivamente, la polvere così ottenuta è stata lavata e centrifugata diverse volte allo scopo di ridurre fino a valori trascurabili la concentrazione di ioni cloruro nell’acqua di lavaggio. Il catalizzatore così ottenuto è stato denominato HP0.5 (Home Prepared bollito per 0.5 h) [1]. Un grammo di tale prodotto è stato sospeso in 3 mL di acqua e sottoposto a sonicazione per 10 minuti. Dopo sedimentazione notturna, la componente solida, non separata dalla fase acquosa, è stata sottoposta ad analisi in rilassometria NMR a ciclo di campo a 4 diverse temperature: 25, 40, 60 e 70°C [2]. I profili ottenuti si possono dividere in due parti. La prima parte, nell’intervallo di frequenze di Larmor protoniche compreso tra 10 e 0.9 MHz, mostra un andamento lineare la cui pendenza non viene influenzata dalle variazioni di temperatura. Questo comportamento è tipico di acqua fortemente legata alla superficie di un mezzo poroso. Per effetto della forte i nterazione con la superficie del biossido di titanio, la dinamica dell’acqua non risente di fluttuazioni nel range di temperature utilizzato. Nell’intervallo di frequenze di Larmor protoniche 0.8-0.01 MHz si osserva un andamento del profilo di tipo Lorentziano in cui i valori delle velocità di rilassamento in funzione della temperatura indicano una dinamica dell’acqua ascrivibile ad un regime di moto veloce. Il comportamento rilassometrico dell’acqua sulla superficie del biossido di titanio nanostrutturato preparato in laboratorio in funzione della temperatura, consente di ipotizzare che esistono due strati di acqua intorno alla superficie del TiO 2 . Il primo è uno strato di acqua immobilizzata, circondato da un secondo strato di acqua mobile. E’ proprio la presenza di acqua fortemente legata e difficilmente rimovibile nell’intervallo di temperature investigato che rende conto della scarsa resa cinetica del catalizzatore in esame rispetto ad anatase cristallino. Riferimenti bibliografici [1] M. Addamo, V. Augugliaro, A. Di Paola, E. García-López, V. Loddo, G. Marcì, R. Molinari, L. Palmisano, M. Schiavello, Preparation, characterization and photoactivity of polycrystalline nanostructured TiO 2 catalysts, J. Phys. Chem. B, 108 (2004) 3303-3310. [2] P. Conte, V. Loddo, C. De Pasquale, V. Marsala, G. Alonzo, L. Palmisano, Nature of interactions at the interface of two water-saturated commercial TiO 2 polymorphs, J. Phys. Chem. C, 117 (2013) 5269-5273.

Aims: Larvae of the red palm weevil (RPW) Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae) feed inside palm stem tissues, making galleries and producing a wet fermenting frass. We characterized the culturable micro-organisms associated with frass produced by tunnelling larvae inside the Canary island date palms and investigated the role of frass and gut bacteria in plant polymers breakdown. Methods and Results: A culture-dependent method was used to isolate bacteria from frass and noninfested palm tissues. Bacterial isolates were grouped into operational taxonomic units based on polymorphisms in the ITS-PCR profiles, and representative isolates were identified by partial sequencing of the 16S rRNA gene. Frass bacteria were dominated by 2,3-butanediol fermenter Enterobacteriaceae. None of the bacterial isolates was able to degrade cellulose; however, cellulolytic and hemicellulolytic bacteria were isolated from the larval gut enrichment cultures. Conclusions: Frass bacteria are specifically associated with the RPW larvae and might play beneficial roles for RPW, other than nutritional, that deserve further investigations. Breakdown of plant polymers probably occurs inside the larvae digestive system. Significance and Impact of the Study: Frass and gut micro-organisms of R. ferrugineus should be included in studies of the interactions between RPW, its plant hosts, and its enemies.

The aim of the dissertation is to offer a modern monograph on the seventeenth-century satirical genre, starting from a theoretical perspective and enriching it through a specific examination of the historical developments and structural constants of the genre. The thesis is divided into three sections, the first (Introduction to the seventeenth-century satire) offers a historical overview of the developments of this kind of satire, and its delineation well in the determination of the corpus examined. The second (Metasatire) is strictly theoretical, and is intended to illustrate the statute of such seventeenth-century satire through the drawing up that is provided by the satirists themselves, whose metaliterary sections included in satires are examined, or side works aimed at a general speculation. The third section (Narration) is ultimately of a structural nature, since it aims, on several levels, to illustrate the narrative strategies that feed the seventeenth-century satirical genre, relying on the main narratological categories and moving from the distinction between the authorial personality of the writer and the literary figure of a moral satirist-narrator who says ?I?.

Reticulitermes lucifugus è una specie di termite diffusa in Italia e che causa gravi danni alle strutture legnose di monumenti storici e artistici. L’intestino delle termiti ospita una comunità microbica di batteri e flagellati, responsabile della degradazione del materiale lignocellulosico. Studi preliminari sulla comunità microbica dei simbionti di R. lucifugus, hanno descritto alcune specie di protozoi, ma non ci sono ancora informazioni sui simbionti batterici. Al fine di caratterizzare la comunità microbica intestinale di R. lucifugus è stato utilizzato un approccio molecolare coltura indipendente e colture di arricchimento per l’isolamento dei batteri cellulosolitici. Per l’analisi coltura indipendente è stata costruita una libreria di geni 16S rRNA a partire dal DNA metagenomico estratto dall’intestino delle termiti. Dei 279 cloni ottenuti 96 sono stati scelti a caso e suddivisi in 34 Unità Tassonomiche operative (OTU) sulla base di analisi ARDRA con 4 enzimi di restrizione. Gli inserti di due cloni rappresentativi delle 4 OTU più numerose sono stati sequenziati e assegnati a tre phyla, Firmicutes, Spirochaetes e “Uncultured Termite Gruppo I” (TG1) che risultano dominanti anche in altre specie di Reticulitermes. Dalle colture di arricchimento su diversi substrati lignocellulosici quali carta, carbossimetilcellulosa (CMC) e legno di diverse specie, sono stati ottenuti oltre 300 isolati 70 dei quali hanno mostrato attività cellulosolitica al test Rosso Congo. Gli isolati più attivi, identificati mediante sequenza parziale del gene ribosomale 16S, sono risultati appartenere al genere Bacillus. I risultati ottenuti, sebbene ancora parziali, mostrano che l'intestino di R. lucifugus ospita una popolazione microbica diversificata. La conoscenza di questi simbionti potrebbe fornire informazioni utili per combattere l'attacco di queste termiti alle strutture legnose.

The most common renewable fuel is ethanol. It is a liquid produced by fermentation of glucose which is very abundant in cellulose based material sources. Plants produce about 180 billion tons of cellulose per year globally. For this reason cellulose is the largest organic carbon reservoir on Earth. Cellulose is composed exclusively of glucose units linked via B-1,4 glycosidic bonds. Each D-(+)-glucose unit contains three hydroxyl groups, which can form complex spatial networks of inter- and intra- molecular hydrogen bonds. They are responsible for the high crystallinity and compactness of cellulose, thereby making it very resistant to biological and chemical attack. In the presence of mineral acid, cellulose is known to undergo hydrolysis whose extent depends on acid concentration, reaction temperature and treatment duration. Cellulose depolymerization is followed by formation of hydrocellulose, soluble polysaccharides, oligosaccharides and/or glucose as by products. Aim of the present study was to evaluate kinetic of glucose formation during cellulose degradation by using 85% phosphoric acid. H3PO4 is a weak mineral acid, non corrosive, non toxic and safer to use as compared to other inorganic mineral acids. It was investigated the role of residence time on the efficiency of glucose release during the hydrolysis of microcrystalline- cellulose in H3PO4 at the constant reaction temperature of 80 °C. Results showed the presence of two competitive reactions. In the interval between 5 and 90 minutes, the system is dominated by cellulose hydrolysis with glucose formation with a kinetic costant of 0.0058 0.0004 mM/min. Above 90 minutes, the reaction appeared dominated by glucose degradation. Glucose yield resulted of 28% after 90 minutes, thereby indicating that 1.5 h, at 80 °C allows the production of the largest amount of glucose from crystalline cellulose.

The most common renewable fuel is ethanol. It is a liquid produced by fermentation of glucose which is very abundant in cellulose based materials. Bioethanol is achieved in a two-steps process: 1. hydrolysis of the cellulose included in the ligno-cellulosic materials to fermentable reducing sugars; 2. fermentation of such sugars to ethanol. While the second fermentation step, mediated by yeasts or bacteria, is very well established, the first one must be still assessed for process optimization. Many efforts have been made to identify solvents for cellulose in order to develop methods for the achievement of fermentable glucose. In the presence of mineral acid, cellulose undergoes hydrolysis whose extent depends on acid concentration, reaction temperature and duration of treatment. In the last years, dissolution in phosphoric acid (a weak mineral acid, non toxic and safer to use as compared to other inorganic acids) has been increasingly considered as a simple and economic method for cellulose pretreatment before its degradation to glucose. Up to now, it has not been reported yet cellulose conversion to glucose in H3PO4 solutions. Aim of the present study was to evaluate kinetic of glucose formation during cellulose degradation by using 85% phosphoric acid. It was investigated the role of residence time on the efficiency of glucose release during the hydrolysis of microcrystalline- cellulose in H3PO4 at the constant reaction temperature of 80°C. Moreover, High field NMR measurements showed that heating treatment is fundamental to have conversion of cellulose in glucose with formation of same degradation products, how supported by GC MS analysis results. In addition, relaxometry measurements with a fast field cycling setup have been carried out in order to observe how heating treatment change the relaxation time distribution of cellulose acid solutions, thereby suggesting that as cellulose degradation occurred , presence of smaller units determined the restoring of the T1 distribution of the complex mixture to a value close to that of pure phosphoric acid.

Previous studies 1,2 have shown that kinematic viscosity values of food oils depend on the presence of added solvents and on the nature of the oil under investigation (e.g., geographical origin and treatments prior to oil production). However, to the best of our knowledge, only one paper 3 dealt with the correlation between viscosity values and relaxation times of simple pure alkyl compounds. Up to now, no papers have been found in literature dealing with viscosity of complex mixtures and their relaxometric properties. In this study, we intended to investigate the effect of kinematic viscosity over the dynamic properties of an extra-virgin olive oil which is known as a very complex mixture of lipophilic triglycerides (more than 98%) and waxes, and hydrophilic secondary metabolites (around 2%) such as chlorophyll, salts and sterols. The relaxometric model 2,4 applied for the analyses of the NMRD profiles of the oil added with increasing amounts of n-hexane, split the correlation time in two contributions. The first one, modulated by an amplitude indicated as AD, was assigned to translational motions (D). The second component of the correlation time, also modulated by an amplitude indicated as AR, was due to the rotational motions (R). Results revealed that all the relaxometric parameters had a diametric trend. A possible explanation for such a behavior was found in the aggregative properties of the inverse micelle-like 1 components of the food oil. In fact, in the absence of n-hexane, all the inverse micelle-like systems, in which triglycerides are shrink together, aggregate, thereby forming large sized units which are subjected to very slow rotations but fast translations. Conversely, as the amount of n-hexane was increased, kinematic viscosity decreased and rotations became preponderant over translations. In fact, n- hexane has the effect to separate the inverse micelle-like systems and to increase rotational freedom degrees over the translational ones. This study confirmed the inverse micelle-like nature of food oils reported in a previous paper 1 .