Influences of deep convective cloud systems on tropospheric trace gases and photochemistry over the tropical West Pacific

A numerical model for studying the influences of deep convective cloud systems on photochemistry was developed based on a non-hydrostatic meteorological model and chemistry from a global chemistry transport model. The transport of trace gases, the scavenging of soluble trace gases, and the influences of lightning produced nitrogen oxides (NOx=NO+NO2) on the local ozone-related photochemistry were investigated in a multi-day case study for an oceanic region located in the tropical western Pacific. Model runs considering influences of large scale flows, previously neglected in multi-day cloud resolving and single column model studies of tracer transport, yielded that the influence of the mesoscale subsidence (between clouds) on trace gas transport was considerably overestimated in these studies. The simulated vertical transport and scavenging of highly soluble tracers were found to depend on the initial profiles, reconciling contrasting results from two previous studies. Influences of the modeled uptake of trace gases by hydrometeors in the liquid and the ice phase were studied in some detail for a small number of atmospheric trace gases and novel aspects concerning the role of the retention coefficient (i.e. the fraction of a dissolved trace gas that is retained in the ice phase upon freezing) on the vertical transport of highly soluble gases were illuminated. Including lightning NOx production inside a 500 km 2-D model domain was found to be important for the NOx budget and caused small to moderate changes in the domain averaged ozone concentrations. A number of sensitivity studies yielded that the fraction of lightning associated NOx which was lost through photochemical reactions in the vicinity of the lightning source was considerable, but strongly depended on assumptions about the magnitude and the altitude of the lightning NOx source. In contrast to a suggestion from an earlier study, it was argued that the near zero upper tropospheric ozone mixing ratios which were observed close to the study region were most probably not caused by the formation of NO associated with lightning. Instead, it was argued in agreement with suggestions from other studies that the deep convective transport of ozone-poor air masses from the relatively unpolluted marine boundary layer, which have most likely been advected horizontally over relatively large distances (both before and after encountering deep convection) probably played a role. In particular, it was suggested that the ozone profiles observed during CEPEX (Central Equatorial Pacific Experiment) were strongly influenced by the deep convection and the larger scale flow which are associated with the intra-seasonal oscillation.

Determination of trace elemental species in periostracum of Cypraea shells

n this work, three Cypraea species (C. talpa, C. tigris and C. zebra) were exhaustively studied. The shells have been separated in the structural layers. The mineralogy, ultra- and micro-structure of each layer were analyzed by Confocal Laser Scanning Microscopy (CLSM), Scanning Electron Microscopy (SEM), X-Ray Diffractometry (XRD) and Raman Spectroscopy (RS). The presence of biologically relevant trace metals (Mn, Co, Fe, Zn, Cr, etc.) has been investigated using Instrumental Neutron Activation Analysis (INAA) and Inductively Coupled Plasma – Mass Spectrometry (ICP-MS) as detection tool. A new method has been developed and optimized to extract and analyze the soluble organic matrix (SOM) of the shell. Although the molecular nature of the SOM is not really known, it contains at least large protein fraction, if not only consists of proteins. The extracted matrices were compared between layers and species using Size Exclusion High Performance Liquid Chromatography coupled with Ultra Violet Spectrometry (SE-HPLC-UV), Gel electrophoresis (GE) and protein quantification tests. For the first time to our knowledge the association of trace elements to the protein in the SOM of the shell was studied using hyphenated on line as well as combined off line techniques and validated through inter-comparison tests between the different methods applied. Interesting correlations between the trace element concentration, the microstructure and the protein content were directly and indirectly detected. The metals Cu, Ni, Co and Zn have shown to bind to the SOM extracted from C. talpa, C. tigris and C. zebra shells. Within the conclusions of this work it was demonstrated that these protein-metal-complexes (or metal containing proteins) change from one layer to the other and are different between the three snails analyzed. In addition, the complexes are clearly related only to certain protein fractions of the SOM, and not to the whole SOM observed. These fractions and show not to be very metal-specific (i.e. some of these fractions bind two or three different metals).

Partial melting within the lower crust – Constraints from bulk rock geochemical data and trace element mineral analyses of granulites and migmatites from Central Finland

This PhD thesis concerns geochemical constraints on recycling and partial melting of Archean continental crust. A natural example of such processes was found in the Iisalmi area of Central Finland. The rocks from this area are Middle to Late Archean in age and experienced metamorphism and partial melting between 2.7-2.63 Ga. The work is based on extensive field work. It is furthermore founded on bulk rock geochemical data as well as in-situ analyses of minerals. All geochemical data were obtained at the Institute of Geosciences, University of Mainz using X-ray fluorescence, solution ICP-MS and laser ablation-ICP-MS for bulk rock geochemical analyses. Mineral analyses were accomplished by electron microprobe and laser ablation ICP-MS. Fluid inclusions were studied by microscope on a heating-freezing-stage at the Geoscience Center, University Göttingen. Part I focuses on the development of a new analytical method for bulk rock trace element determination by laser ablation-ICP-MS using homogeneous glasses fused from rock powder on an Iridium strip heater. This method is applicable for mafic rock samples whose melts have low viscosities and homogenize quickly at temperatures of ~1200°C. Highly viscous melts of felsic samples prevent melting and homogenization at comparable temperatures. Fusion of felsic samples can be enabled by addition of MgO to the rock powder and adjustment of melting temperature and melting duration to the rock composition. Advantages of the fusion method are low detection limits compared to XRF analyses and avoidance of wet-chemical processing and use of strong acids as in solution ICP-MS as well as smaller sample volumes compared to the other methods. Part II of the thesis uses bulk rock geochemical data and results from fluid inclusion studies for discrimination of melting processes observed in different rock types. Fluid inclusion studies demonstrate a major change in fluid composition from CO2-dominated fluids in granulites to aqueous fluids in TTG gneisses and amphibolites. Partial melts were generated in the dry, CO2-rich environment by dehydration melting reactions of amphibole which in addition to tonalitic melts produced the anhydrous mineral assemblages of granulites (grt + cpx + pl ± amph or opx + cpx + pl + amph). Trace element modeling showed that mafic granulites are residues of 10-30 % melt extraction from amphibolitic precursor rocks. The maximum degree of melting in intermediate granulites was ~10 % as inferred from modal abundances of amphibole, clinopyroxene and orthopyroxene. Carbonic inclusions are absent in upper-amphibolite facies migmatites whereas aqueous inclusion with up to 20 wt% NaCl are abundant. This suggests that melting within TTG gneisses and amphibolites took place in the presence of an aqueous fluid phase that enabled melting at the wet solidus at temperatures of 700-750°C. The strong disruption of pre-metamorphic structures in some outcrops suggests that the maximum amount of melt in TTG gneisses was ~25 vol%. The presence of leucosomes in all rock types is taken as the principle evidence for melt formation. However, mineralogical appearance as well as major and trace element composition of many leucosomes imply that leucosomes seldom represent frozen in-situ melts. They are better considered as remnants of the melt channel network, e.g. ways on which melts escaped from the system. Part III of the thesis describes how analyses of minerals from a specific rock type (granulite) can be used to determine partition coefficients between different minerals and between minerals and melt suitable for lower crustal conditions. The trace element analyses by laser ablation-ICP-MS show coherent distribution among the principal mineral phases independent of rock composition. REE contents in amphibole are about 3 times higher than REE contents in clinopyroxene from the same sample. This consistency has to be taken into consideration in models of lower crustal melting where amphibole is replaced by clinopyroxene in the course of melting. A lack of equilibrium is observed between matrix clinopyroxene / amphibole and garnet porphyroblasts which suggests a late stage growth of garnet and slow diffusion and equilibration of the REE during metamorphism. The data provide a first set of distribution coefficients of the transition metals (Sc, V, Cr, Ni) in the lower crust. In addition, analyses of ilmenite and apatite demonstrate the strong influence of accessory phases on trace element distribution. Apatite contains high amounts of REE and Sr while ilmenite incorporates about 20-30 times higher amounts of Nb and Ta than amphibole. Furthermore, trace element mineral analyses provide evidence for magmatic processes such as melt depletion, melt segregation, accumulation and fractionation as well as metasomatism having operated in this high-grade anatectic area.

Progettazione di mozzi ruota per vettura da formula SAE

Progettazione dei mozzi ruota della vettura 2012 del team UniBo Motorsport, il team di formula SAE dell'università di Bologna.

Dupire's formula for exponential Lévy models

Questa tesi è incentrata sull'analisi della formula di Dupire, che permette di ottenere un'espressione della volatilità locale, nei modelli di Lévy esponenziali. Vengono studiati i modelli di mercato Merton, Kou e Variance Gamma dimostrando che quando si è off the money la volatilità locale tende ad infinito per il tempo di maturità delle opzioni che tende a zero. In particolare viene proposta una procedura di regolarizzazione tale per cui il processo di volatilità locale di Dupire ricrea i corretti prezzi delle opzioni anche quando si ha la presenza di salti. Infine tale risultato viene provato numericamente risolvendo il problema di Cauchy per i prezzi delle opzioni.

The development and deployment of FOTOS: a fast observation of trace organics system

Flüchtige organische Bestandteile (engl.: VOC) sind in der Atmosphäre in Spuren vorhanden, spielen aber trotzdem eine wichtige Rolle in der Luftchemie: sie beeinflussen das Ozon der Troposphäre, städtischen Smog, Oxidationskapazität und haben direkte und indirekte Auswirkungen auf die globale Klimaveränderung. Eine wichtige Klasse der VOC sind die Nicht-Methan-Kohlenwasserstoffe (engl.: NMHC), die überwiegend von anthropogenen Quellen kommen. Aus diesem Grund ist für Luftchemiker ein Messinstrument nötig, das die VOC, die NMHC eingeschlossen, mit einer höheren Zeitauflösung misst, besonders für Echtzeitmessungen an Bord eines Forschungsflugzeuges. Dafür wurde das System zur schnellen Beobachtung von organischen Spuren (engl.: FOTOS) entworfen, gebaut für den Einsatz in einem neuen Wissenschaftlichen Flugzeug, das in großen Höhen und über weite Strecken fliegt, genannt HALO. In der Folge wurde FOTOS in zwei Messkampagnen am Boden getestet. FOTOS wurde entworfen und gebaut mit einem speziell angefertigten, automatisierten, kryogenen Probensystem mit drei Fallen und einem angepassten, erworbenen schnellen GC-MS. Ziel dieses Aufbaus war es, die Vielseitigkeit zu vergrößern und das Störungspotential zu verringern, deshalb wurden keine chemischen Trocknungsmittel oder adsorbierenden Stoffe verwendet. FOTOS erreichte eine Probenfrequenz von 5.5 Minuten, während es mindestens 13 verschiedene C2- bis C5-NMHC maß. Die Drei-Sigma-Detektionsgrenze für n- und iso-Pentan wurde als 2.6 und 2.0 pptv ermittelt, in dieser Reihenfolge. Labortests bestätigten, dass FOTOS ein vielseitiges, robustes, hochautomatisiertes, präzises, genaues, empfindliches Instrument ist, geeignet für Echtzeitmessungen von VOC in Probenfrequenzen, die angemessen sind für ein Forschungsflugzeug wie HALO. Um die Leistung von FOTOS zu bestätigen, wurde vom 26. Januar bis 4. Februar 2010 ein Zwischenvergleich gemacht mit dem GC-FID-System am Meteorologischen Observatorium Hohenpeißenberg, einer WMO-GAW-globalen Station. Dreizehn verschiedene NMHC wurden innerhalb des Rahmens der GWA Data Quality Objectives (DQO) analysiert und verglichen. Mehr als 80% der Messungen von sechs C3- bis C5-NMHC erfüllten diese DQO. Diese erste Messkampagne im Feld hob die Robustheit und Messgenauigkeit von FOTOS hervor, zusätzlich zu dem Vorteil der höheren Probenfrequenz, sogar in einer Messung am Boden. Um die Möglichkeiten dieses Instrumentes im Feld zu zeigen, maß FOTOS ausgewählte leichte NMHC während einer Messkampagne im Borealen Waldgebiet, HUMPPA-COPEC 2010. Vom 12. Juli bis zum 12. August 2010 beteiligte sich eine internationale Gruppe von Instituten und Instrumenten an Messungen physikalischer und chemischer Größen der Gas- und Partikelphasen der Luft über dem Borealen Wald an der SMEAR II-Station nahe Hyyttiälä, Finnland. Es wurden mehrere Hauptpunkte von Interesse im Mischungsverhältnis der Alkane und im Isomerenverhätnis von Pentan identifiziert, insbesondere sehr unterschiedliche Perioden niedriger und hoher Variabilität, drei Rauchschwaden von Biomassen-Verbrennung von russischen Waldbränden und zwei Tage mit extrem sauberer Luft aus der Polarregion. Vergleiche der NMHC mit anderen anthropogenen Indikatoren zeigten mehrere Quellen anthropogener Einflüsse am Ort auf und erlaubten eine Unterscheidung zwischen lokalen und weiter entfernten Quellen. Auf einen minimalen natürlichen Beitrag zum 24h-Kreislauf von NOx wurde geschlussfolgert aus der Korrelation von NOx mit Alkanen. Altersschätzungen der Luftmassen durch das Isomerenverhältnis von Pentan wurden erschwert durch sich verändernde Verhältnisse der Quellen und durch Besonderheiten der Photochemie während des Sommers im hohen Norden. Diese Messungen zeigten den Wert des Messens leichter NMHC, selbst in abgelegenen Regionen, als einen zusätzlichen spezifischen Marker von anthropogenem Einfluss.

Formula integrale di Poisson per le funzioni armoniche in una palla

La tesi consiste nella ricerca di un candidato ideale per la soluzione del problema di Dirichlet. Vengono affrontati gli argomenti in maniera graduale, partendo dalle funzioni armoniche e le loro relative proprietà, passando per le identità e le formule di rappresentazione di Green, per finire nell'analisi del problema sopra citato, mediante i risultati precedentemente ottenuti, per concludere trovando la formula integrale di Poisson come soluzione ma anche come formula generale per sviluppi in vari ambiti.

La formula di Eulero per i poliedri fra storia e didattica

Questa tesi riguarda la formula di Eulero per i poliedri: F - S + V = 2 dove F indica il numero di facce, S il numero di spigoli e V quello dei vertici di un poliedro. Nel primo capitolo tratteremo i risultati ottenuti da Cartesio: egli fu il primo a considerare non solo le caratteristiche geometriche ma anche metriche di un solido. Partendo dall'analogia con le figure piane, riuscì a ricavare importanti relazioni nei solidi convessi, riguardanti il numero e la misura degli angoli piani, degli angoli solidi e delle facce. Non arrivò mai alla formulazione conosciuta oggi ma ne intuì le caratteristiche topologiche, che però non dimostrò mai. Nel secondo capitolo invece ci occuperemo di ciò che scoprì Eulero. Il manoscritto contenente i risultati di Cartesio era scomparso e quindi questi non erano più conosciuti dai matematici; Eulero, in accordo con quanto avviene per i poligoni, desiderava ottenere un metodo di classificazione per i poliedri e si mise a studiare le loro proprietà. Oltre alla sua formula, in un primo articolo ricavò importanti relazioni, e in un secondo lavoro ne propose una dimostrazione. Riportiamo in breve anche un confronto tra il lavoro di Cartesio e quello di Eulero. Il terzo capitolo invece riguarda il metodo e il rigore nella formulazione di teoremi e dimostrazioni: I. Lakatos ne fa un esame critico nel libro "Dimostrazioni e Confutazioni - la logica della scoperta matematica", simulando una lezione dove a tema compaiono la Formula di Eulero e le sue dimostrazioni. Noi cercheremo di analizzare questo suo lavoro. Su questi tre autori e i loro lavori riportiamo alcune considerazioni biografiche e storiche che possono offrire interessanti spunti didattici: infatti nel quarto e ultimo capitolo ci occuperemo di alcune considerazioni didattiche a proposito della Formula. La struttura sarà quella di un'ipotetica lezione a studenti di Scuola Media Inferiore e utilizzeremo i risultati ottenuti nei precedenti capitoli e una personale esperienza di tirocinio.

Progettazione del sistema di controllo di una vettura di formula sae

Il seguente lavoro di tesi è finalizzato alla realizzazione dell’elettronica di controllo per una vettura prototipo, Nel Capitolo 1 della tesi viene descritto più nel dettaglio il progetto Formula SAE, introducendo gli aspetti peculiari della competizione; successivamente segue una breve descrizione del team UniBo Motorsport. Il Capitolo 2 descrive l’elettronica implementata nella stagione 2013 evidenziandone i punti di forza e le debolezze al fine di poter trarre delle conclusioni per comprendere la direzione intrapresa con questo lavoro di tesi. Nel Capitolo 3 viene presentata la soluzione proposta,motivandone le scelte e la necessità di suddividere il lavoro in più unità distinte, mantenendo le peculiarità tecniche del già eccellente lavoro effettuato nel corso degli anni da chi mi ha preceduto ed aggiungendo quelle funzionalità che permettono di mantenere la soluzione in una posizione dominante nel panorama della Formula Student. La progettazione dell’hardware che compone la soluzione proposta è descritta nel Capitolo 4, introducendo dapprima la metodologia adottata per la progettazione partendo dalle specifiche fino ad arrivare al prodotto finito ed in seguito ne viene descritta l’applicazione ad ogni unità oggetto del lavoro. Sono state progettate da zero tre unità: una centralina di controllo motore (ECU), una di controllo veicolo (VCU) ed un controller lambda per la gestione di sonde UEGO. Un aiuto fondamentale nella progettazione di queste tre unità è stato dato da Alma Automotive, azienda che fin dal principio ha supportato, anche economicamente, le varie evoluzioni dell’hardware e del software della vettura. Infine viene descritto nel capitolo 5 il software che verrà eseguito sulle unità di controllo, ponendo particolare risalto al lavoro di adattamento che si è reso necessario per riutilizzare il software in uso negli anni precedenti.

Taylor formula for Kolmogorov equations

After briefly discuss the natural homogeneous Lie group structure induced by Kolmogorov equations in chapter one, we define an intrinsic version of Taylor polynomials and Holder spaces in chapter two. We also compare our definition with others yet known in literature. In chapter three we prove an analogue of Taylor formula, that is an estimate of the remainder in terms of the homogeneous metric.

The Feynman-Kac formula and applications to PDEs

The thesis presents a probabilistic approach to the theory of semigroups of operators, with particular attention to the Markov and Feller semigroups. The first goal of this work is the proof of the fundamental Feynman-Kac formula, which gives the solution of certain parabolic Cauchy problems, in terms of the expected value of the initial condition computed at the associated stochastic diffusion processes. The second target is the characterization of the principal eigenvalue of the generator of a semigroup with Markov transition probability function and of second order elliptic operators with real coefficients not necessarily self-adjoint. The thesis is divided into three chapters. In the first chapter we study the Brownian motion and some of its main properties, the stochastic processes, the stochastic integral and the Itô formula in order to finally arrive, in the last section, at the proof of the Feynman-Kac formula. The second chapter is devoted to the probabilistic approach to the semigroups theory and it is here that we introduce Markov and Feller semigroups. Special emphasis is given to the Feller semigroup associated with the Brownian motion. The third and last chapter is divided into two sections. In the first one we present the abstract characterization of the principal eigenvalue of the infinitesimal generator of a semigroup of operators acting on continuous functions over a compact metric space. In the second section this approach is used to study the principal eigenvalue of elliptic partial differential operators with real coefficients. At the end, in the appendix, we gather some of the technical results used in the thesis in more details. Appendix A is devoted to the Sion minimax theorem, while in appendix B we prove the Chernoff product formula for not necessarily self-adjoint operators.

Interpretazione per i media: il caso particolare delle interviste sul podio della Formula 1

This dissertation analyses the live simultaneous interpretation from English into Italian of six 2013 Formula 1 World Championship podium interviews and focuses on four main aspects: how the interpreter handled the décalage at the end of the interview and during the turn-taking; if he used any marker to indicate that he was starting to translate a new turn of the source text; what he did when overlapped speech in the source texts occurred; what happened when the Italian commentators talked during the interpreter’s translation. In the first chapter a description mainly of what a Formula 1 podium interview is and what an interpreter translates during the Formula 1 weekends is present. In the second chapter a literature review on media interpreting, with particular attention put on Straniero Sergio’s paper on translating Formula 1 press-conferences (2003), and turn-taking is provided. In the third chapter the methodology used to obtain and process the video and audio files of source and target texts and to transcribe them is described. We concentrated primarily on Thibault’s multimodal text transcription techniques (2000) and on how they were used and adapted to fit the purposes of this dissertation. In the fourth chapter the results obtained through the analysis of the source and target texts are shown and described, focusing only on the objectives of the dissertation, without aiming to provide a qualitative evaluation of the interpretations. In the fifth and last chapter the conclusions and some final remarks are made, based on the results obtained during the analysis and the hope for a more in depth knowledge of Italian Formula 1 interpreter’s working conditions.

Formula Zero: Traduzione trilingue inglese-italiano-spagnolo di un policy statement sulla sicurezza stradale della Federazione Internazionale dell'Automobile (FIA)

The aim of this dissertation is to provide a trilingual translation from English into Italian and from Italian into Spanish of a policy statement from the Fédération Internationale de l’Automobile (FIA) regarding road safety. The document, named “Formula Zero: a strategy for reducing fatalities and injuries on track and road”, was published in June 2000 and involves an approach about road safety inspired by another approach introduced in Sweden called ‘Vision Zero’. This work consists of six sections. The first chapter introduces the main purposes and activities of the Federation, as well as the institutions related to it and Vision Zero. The second chapter presents the main lexical, morphosyntactic and stylistic features of the institutional texts and special languages. In particular, the text contains technical nomenclature of transports and elements of sport language, especially regarding motor sport and Formula One. In the third chapter, the methodology is explained, with all the resources used during the preliminary phase and the translation, including corpora, glossaries, expert consultancy and specialised sites. The fourth chapter focuses on the morphosyntactic and terminology features contained in the text, while the fifth chapter presents the source text and the target texts. The final chapter deals with all the translation strategies that are applied, alongside with all the challenging elements detected. Therefore, the dissertation concludes with some theoretical and practical considerations about the role of inverse translation and English as Lingua Franca (ELF), by comparing the text translated into Spanish to the original in English, using Italian as a lingua franca.