O estudo da usinagem em torneamento da superliga à base de níquel Pyromet 31v

The search for materials with higher properties and characteristics (wear resistance, oxidation, corrosion, etc.) has driven research of various materials. Among the materials that are being studied with such properties and characteristics are super alloys based on nickel which has an important role in the aeronautical, automotive, marine, production of gas turbines and now in space vehicles, rocket engineering , experimental aircraft, nuclear reactors, steam-powered plants, petrochemical and many other applications because besides having all the characteristics and properties mentioned above also have an excellent performance at high temperatures. The super alloy based on nickel studied in this work is the super alloy Pyromet 31v normally used in the manufacture of exhaust valves in common engines and diesel engines of high power by cater requirements such as mechanical strength and corrosion resistance at temperatures of approximately 815 ° C. The objective of this work is to produce results to demonstrate more specific information about the real influence of coatings on cutting tools and cutting fluids in turning and thus promote the optimization of the machining of these alloys. The super alloy Pyromet 31v was processed through turning, being performed with various machining parameters such as cutting speed, feed rate, depth in conditions of Minimum Amount of Fluid (MAF), abundant fluid, cutting tools with coating and without coating in early in his work life and with wear. After turning were obtained several samples of chips and the part generated during the machining process, was measured roughness of the material, subsequently made macrostructural analysis of the tools used order to detect possible wear and microstructural analysis of samples collected being that the latter was used for Optical Microscopy, Scanning Electron Microscopy (SEM) and ... (Complete abstract click electronic access below)

Basquetebol X temas transversais: a produção de material didático audiovisual para a Educação Física escolar

This study aimed, first, produce a kind of educational materials in audiovisual format, to the Physical Education, addressing the Transversal Themes in view of the basketball. The themes chosen were Cultural Plurality, addressing the basketball in a wheelchair, and Labor and Consumer Affairs, addressing the marketing and exploitation of labor force that the company is Nike. There is no doubt the importance of media production in contemporary society, as one of its main languages, but of little relevance in the school environment, especially in the area of Physical Education. In a second phase aimed at evaluating the feasibility of this material both as a teaching strategy, such as content of learning lessons. The evaluation was made through a discussion in the form of focus groups with 10 students from 9 th grade of elementary school. The results showed that despite an initial rejection of the material as a teaching strategy because of the history that Physical Education has for several years, students were open to new ways of learning. Since the results on the material, such as learning content, showed that the videos were able to address and the Transversal Themes and meet the need for procedural content with the proposed activities. With this, we realize that students are willing to discuss matters that are not always addressed, but now, with the creation of national curriculum standards should be reflected in the classroom

Projeto e análise de um sistema de ancoragem para um motor foguete a combustível líquido

This work aims the design and analysis of a thrust frame system for a liquid fuel rocket engine. The project was developed following the design requirements established by the Division of Space Propulsion of the Institute of Aeronautics and Space. The layout of the structure was developed with the aid of a software of 3D modeling and static and dynamic analysis were performed by using a finite element package. The results of the analyzes helped in defining the layout of the structure which met all design requirements. The safety factor and the mass achieved were comfortably low, which may be useful in the future because the liquid fuel rocket engine is still in development

Análise de um cilindro submetido à excitação acústica por camada limite turbulenta

A launching rocket and its payload are submitted to strong acoustic loads in some moments of its flight like lift off, during transonic flight and in the instant of maximum dynamic pressure. These loads could affect the payload and other rocket internal equipment. It must be taken into account that in the higher stages, where delicate control equipment and the payload are placed, the acoustic excitations are dominant. The knowledge of the acoustic loads is of great importance in order to provide estimated loads for the design phase, define intensity level to specify qualification and acceptation acoustic tests to which subsystems and elements of the launcher and its payload shall be submitted and to design an acoustic … (Complete abstract click electronic access below)

Adubação nitrogenada para consórcio de alface e rúcula

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Caracterização de juntas soldadas em PAW e GTAW de chapas finas em aço maraging 300 submetidas a vários reparos

Pós-graduação em Engenharia Mecânica - FEG

Projeto de adaptação do sistema de injeção do túnel transônico para ensaios em bocais de foguete

In this work, the project of a new experimental facility to be installed at the Aerodynamics Division of the Institute of Aeronautics and Space is presented. This new facility will provide means to perform experimental campaigns to analyze the flow behavior at different rocket nozzle concepts using cold gas that will be obtained from a modification of the Pilot Transonic Wind Tunnel air system. The new installation will enable less expensive experiments in a more secure environment, since the cold gas experimental procedures do not demand fuel storage and burn and security procedures are much less severe. Furthermore, experiments can be carried with different types of sensors, commonly used in wind tunnel tests. Also, the optical access is facilitated enabling the use of optical techniques for the characterization of flow properties inside the nozzles, such as pressure and temperature sensitive painting. The full project design and the operation conditions will be showed, as also some technical considerations about the flor behavior in the facility

Projeto de adaptação do sistema de injeção do túnel transônico para ensaios em bocais de foguete

In this work, the project of a new experimental facility to be installed at the Aerodynamics Division of the Institute of Aeronautics and Space is presented. This new facility will provide means to perform experimental campaigns to analyze the flow behavior at different rocket nozzle concepts using cold gas that will be obtained from a modification of the Pilot Transonic Wind Tunnel air system. The new installation will enable less expensive experiments in a more secure environment, since the cold gas experimental procedures do not demand fuel storage and burn and security procedures are much less severe. Furthermore, experiments can be carried with different types of sensors, commonly used in wind tunnel tests. Also, the optical access is facilitated enabling the use of optical techniques for the characterization of flow properties inside the nozzles, such as pressure and temperature sensitive painting. The full project design and the operation conditions will be showed, as also some technical considerations about the flor behavior in the facility

PRODUCTION AND CHEMICAL COMPOSITION OF VEGETABLES HARDWOOD IN HYDROPONICS

The hydroponic cultivation of vegetables has increased markedly in recent years, however, little is known about its chemical composition, which is of extreme importance in view of changing food habits of a considerable fraction of the population seeking food quality. For this reason, cultivation of watercress, chicory, rocket and lettuce American (Lucy Brown) and smooth (cv. Regina) were grown in hydroponics, NFT system, aiming to evaluate the yield, nitrate content and chemical composition. The experiment was conducted in a greenhouse at the Universidade Federal de Santa Catarina, Florianopolis city in the Santa Catarina State (Brazil), from may to july 2004 under a completely randomized design with four replications. The spacing used was 25 x 25 cm for the crops of watercress, chicory and lettuce (cv. Lucy Brown and cv. Regina) and 5 x 5 cm to the rocket. The traits were: number of leaves, nitrate content and chemical composition of vegetables. The lettuce cv. Regina and chicory had higher number of leaves per plant. The watercress had lower water content and higher dry mass of shoots. The largest increase in fresh weight was obtained in chicory, lettuce, cv. Regina. Higher levels of lipids, protein, ash, carbohydrates, calories, fiber and nitrate were obtained from the watercress. The rocket had lower values for the variables fresh and dries the whole plant, shoot and root and leaf number per plant. All cultures showed good visual appearance, low calorie and nitrate levels suitable for human consumption.

Bioactive and toxic compounds in different foodstuffs: analytical techniques and sensory analysis

Foods that provide medical and health benefits or have a role in disease risk prevention are termed functional foods. The functionality of functional foods is derived from bioactive compounds that are extranutritional constituents present in small quantities in food. Bioactive components include a range of chemical compounds with varying structures such as carotenoids, flavonoids, plant sterols, omega-3 fatty acids (n-3), allyl and diallyl sulfides, indoles (benzopyrroles), and phenolic acids. The increasing consumer interest in natural bioactive compounds has brought about a rise in demand for these kinds of compounds and, in parallel, an increasing number of scientific studies have this type of substance as main topic. The principal aim of this PhD research project was the study of different bioactive and toxic compounds in several natural matrices. To achieve this goal, chromatographic, spectroscopic and sensorial analysis were performed. This manuscript reports the main results obtained in the six activities briefly summarized as follows: • SECTION I: the influence of conventional packaging on lipid oxidation of pasta was evaluated in egg spaghetti. • SECTION II: the effect of the storage at different temperatures of virgin olive oil was monitored by peroxide value, fatty acid activity, OSI test and sensory analysis. • SECTION III: the glucosinolate and phenolic content of 37 rocket salad accessions were evaluated, comparing Eruca sativa and Diplotaxis tenuifolia species. Sensory analysis and the influence of the phenolic and glucosinolate composition on sensory attributes of rocket salads has been also studied. • SECTION IV: ten buckwheat honeys were characterised on the basis of their pollen, physicochemical, phenolic and volatile composition. • SECTION V: the polyphenolic fraction, anthocyanins and other polar compounds, the antioxidant capacity and the anty-hyperlipemic action of the aqueous extract of Hibiscus sabdariffa were achieved. • SECTION VI: the optimization of a normal phase high pressure liquid chromatography–fluorescence detection method for the quantitation of flavanols and procyanidins in cocoa powder and chocolate samples was performed.

Modellazione Tridimensionale del Processo di Combustione di un Razzo a Propellente Solido

La regolazione dei sistemi di propulsione a razzo a propellente solido (Solid Rocket Motors) ha da sempre rappresentato una delle principali problematiche legate a questa tipologia di motori. L’assenza di un qualsiasi genere di controllo diretto del processo di combustione del grano solido, fa si che la previsione della balistica interna rappresenti da sempre il principale strumento utilizzato sia per definire in fase di progetto la configurazione ottimale del motore, sia per analizzare le eventuali anomalie riscontrate in ambito sperimentale. Variazioni locali nella struttura del propellente, difettosità interne o eterogeneità nelle condizioni di camera posso dare origine ad alterazioni del rateo locale di combustione del propellente e conseguentemente a profili di pressione e di spinta sperimentali differenti da quelli previsti per via teorica. Molti dei codici attualmente in uso offrono un approccio piuttosto semplificato al problema, facendo per lo più ricorso a fattori correttivi (fattori HUMP) semi-empirici, senza tuttavia andare a ricostruire in maniera più realistica le eterogeneità di prestazione del propellente. Questo lavoro di tesi vuole dunque proporre un nuovo approccio alla previsione numerica delle prestazioni dei sistemi a propellente solido, attraverso la realizzazione di un nuovo codice di simulazione, denominato ROBOOST (ROcket BOOst Simulation Tool). Richiamando concetti e techiche proprie della Computer Grafica, questo nuovo codice è in grado di ricostruire in processo di regressione superficiale del grano in maniera puntuale, attraverso l’utilizzo di una mesh triangolare mobile. Variazioni locali del rateo di combustione posso quindi essere facilmente riprodotte ed il calcolo della balistica interna avviene mediante l’accoppiamento di un modello 0D non-stazionario e di uno 1D quasi-stazionario. L’attività è stata svolta in collaborazione con l’azienda Avio Space Division e il nuovo codice è stato implementato con successo sul motore Zefiro 9.

Studio e ricostruzione delle distribuzioni granulometriche interne al grano in motori a propellente solido

The main purposes of this essay were to investigate in detail the burning rate anomaly phenomenon, also known as "Hump Effect", in solid rocket motors casted in mandrel and the mechanisms at the base of it, as well as the developing of a numeric code, in Matlab environment, in order to obtain a forecasting tool to generate concentration and orientation maps of the particles within the grain. The importance of these analysis is due to the fact that the forecasts of ballistics curves in new motors have to be improved in order to reduce the amount of experimental tests needed for the characterization of their ballistic behavior. This graduate work is divided into two parts. The first one is about bidimensional and tridimensional simulations on z9 motor casting process. The simulations have been carried out respectively with Fluent and Flow 3D. The second one is about the analysis of fluid dynamic data and the developing of numeric codes which give information about the concentration and orientation of particles within the grain based on fluid strain rate information which are extrapolated from CFD software.

Studien zu verkleinerten rundplastischen Kaiserporträts von Augustus bis Septimius Severus

Thema der Untersuchung sind kleinformatige rundplastische Kaiserporträts des 1. und 2. Jh. n. Chr., deren Existenz zunächst lange angezweifelt wurde. Da weder ein quantitativer Wert für "kleinformatig" noch eine antike Definition für das Phänomen existieren, kann der Begriff willkürlich definiert werden. Römische Herrscherporträts folgen strengen typologischen Richtlinien, deren Begründung in der Produktionsweise der Kopistenwerkstätten liegt. Auch Verkleinerungen römischer Kaiserporträts zeigen die für einen Bildnistypus bestimmenden Merkmale. Nicht ausgeschlossen werden kann jedoch – und auch zeitgenössische Textquellen sprechen dafür -, daß daneben weitere Bildnisse existierten, hergestellt vielleicht aus billigeren, vergänglichen oder schnell reproduzierbaren Materialien, die sich dieser Identifikationsmethode entziehen. Der Vergleich des Bestandes zeigt große Diskrepanzen hinsichtlich der Überlieferung und auch der Qualität. Oft kommt durch stilistische Mittel und durch Modifikationen in Physiognomie und Habitus ein sentimentales Element hinzu, das bei großformatigen Repliken nicht beobachtbar ist, und das in manchen Fällen sogar der inhaltlichen Aussage des ursprünglichen Bildniskonzepts konträr entgegensteht. Das weist möglicherweise auf eine persönlichere und emotionale Bindung des Betrachters zum Objekt und über dieses zum Dargestellten hin. Daß diese emotionale Ebene der Rezeption existierte, wird auch aus Schriftquellen deutlich. Die primäre Funktion des Kaiserporträts, nämlich Herrscherrepräsentation, wird bei einigen der kleinformatigen Bildnisse durch diese persönliche Ebene überlagert.

Sviluppo dell'interfaccia per il caricamento della geometria iniziale del propellente solido di un modello balistico

Il presente lavoro di tesi, nell’ambito della simulazione balistica di razzi a propellente solido, è volto alla creazione di un’interfaccia che permetta il caricamento delle geometrie dei motori desiderati, in formato SPP, nel codice di simulazione balistica ROBOOST come richiesto da Avio Spa. In particolare saranno descritte le procedure attraverso le quali tale interfaccia è stata realizzata e verranno analizzati i passaggi mediante i quali è possibile ottenere una mesh 3D del motore a propellente solido partendo dalla sua geometria in formato SPP. Si analizzerà inoltre il processo di chiusura di una mesh estratta da una qualsiasi iterazione della simulazione al fine di potervi effettuare delle simulazioni CFD sempre su richiesta della sopracitata azienda. Infine verranno mostrati e discussi i risultati ottenuti per meglio visualizzare il lavoro svolto.