998 resultados para Albatross IV (1963)


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Análise estratégica. Formulação estratégica.

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Introdução. Análise Estratégica. Formulação Estratégica. Desafios Científicos e Tecnológicos. Desafios Institucionais e Organizacionais. Análise do Ambiente Externo. Tendências para o ambiente de atuação. Principais Oportunidades e Ameaças. Definição preliminar de Oportunidade de Cooperação Tecnológica. Missão. Visão de futuro. Valores. Objetivos Estratégicos.

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2009

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Introdução; Análise estratégica; Principais oportunidades e principais ameaças; Formulação estratégica; Desafios científicos e tecnológicos; Colaboradores.

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Wydział Filologii Polskiej i Klasycznej: Instytut Filologii Polskiej

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This article presents the physical structure of the land, organic substances content and the chemical composition of soil comprising subsoil of 21 urban greenery locations in the city of Poznań. As they tend to be commonly underestimated, they have also been presented with view to their vital functions in plants’ life processes. The analysed microelements are referred to their levels, the so-called geo-chemical background of Polish soils and the limit values for field soils with medium levels of nutrients.

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Semiconductor nanowires, particularly group 14 semiconductor nanowires, have been the subject of intensive research in the recent past. They have been demonstrated to provide an effective, versatile route towards the continued miniaturisation and improvement of microelectronics. This thesis aims to highlight some novel ways of fabricating and controlling various aspects of the growth of Si and Ge nanowires. Chapter 1 highlights the primary technique used for the growth of nanowires in this study, namely, supercritical fluid (SCF) growth reactions. The advantages (and disadvantages) of this technique for the growth of Si and Ge nanowires are highlighted, citing numerous examples from the past ten years. The many variables involved in this technique are discussed along with the resultant characteristics of nanowires produced (diameter, doping, orientation etc.). Chapter 2 outlines the experimental methodologies used in this thesis. The analytical techniques used for the structural characterisation of nanowires produced are also described as well as the techniques used for the chemical analysis of various surface terminations. Chapter 3 describes the controlled self-seeded growth of highly crystalline Ge nanowires, in the absence of conventional metal seed catalysts, using a variety of oligosilylgermane precursors and mixtures of germane and silane compounds. A model is presented which describes the main stages of self-seeded Ge nanowire growth (nucleation, coalescence and Ostwald ripening) from the oligosilylgermane precursors and in conjunction with TEM analysis, a mechanism of growth is proposed. Chapter 4 introduces the metal assisted etching (MAE) of Si substrates to produce Si nanowires. A single step metal-assisted etch (MAE) process, utilising metal ion-containing HF solutions in the absence of an external oxidant, was developed to generate heterostructured Si nanowires with controllable porous (isotropically etched) and non-porous (anisotropically etched) segments. In Chapter 5 the bottom-up growth of Ge nanowires, similar to that described in Chapter 3, and the top down etching of Si, described in Chapter 4, are combined. The introduction of a MAE processing step in order to “sink” the Ag seeds into the growth substrate, prior to nanowire growth, is shown to dramatically decrease the mean nanowire diameters and to narrow the diameter distributions. Finally, in Chapter 6, the biotin – streptavidin interaction was explored for the purposes of developing a novel Si junctionless nanowire transistor (JNT) sensor.

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This thesis focuses on the synthesis and analysis of novel chloride based platinum complexes derived from iminophosphine and phosphinoamide ligands, along with studies on their reactivity towards substitution and oxidation reactions. Also explored here are the potential applications of these complexes for biological and luminescent purposes. Chapter one provides an extensive overview of platinum coordination chemistry with examples of various mixed donor ligands along with the history of platinum anticancer therapy. It also looks at metals in medicine, both for biological functions as well as for therapeutic purposes and gives a background to some other applications for platinum complexes. Chapter two outlines the design and synthetic strategies employed for the development of novel platinum (II) chloride complexes from iminophosphine and phosphinoamide ligands. Also reported is the cyclometallation of these complexes to form stable tridentate mixed donor platinum (II) compounds. In Chapter three the development of a direct method for displacing a chloride from a platinum metal centre with a desired phosphine is reported. Numerous methods for successful oxidation of the platinum (II) complexes will also be explored, leading to novel platinum (IV) complexes being reported here also. The importance of stabilisation of the displaced anion, chloride, by the solvent system will also be discussed in this chapter. Chapter four investigates the reactivity of the platinum (II) complexes towards two different biomolecules to form novel platinum bio-adducts. The potential application of the platinum (II) cyclometallates as chemotherapeutics will also be explored here using in-vitro cancer cell testing. Finally, luminescence studies are also reported here for the ligands and platinum complexes reported in chapter two and three to investigate potential applications in this field also. Chapter five provides a final conclusion and an overall summary of the entire project as well as identifying key areas for future work.

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Group IV materials such as silicon nanocrystals (Si NCs) and carbon quantum dots (CQDs) have received great attention as new functional materials with unique physical/chemical properties that are not found in the bulk material. This thesis reports the synthesis and characterisation of both types of nanocrystal and their application as fluorescence probes for the detection of metal ions. In chapter 2, a simple method is described for the size controlled synthesis of Si NCs within inverse micelles having well defined core diameters ranging from 2 to 6 nm using inert atmospheric synthetic methods. In addition, ligands with different molecular structures were utilised to reduce inter-nanocrystal attraction forces and improve the stability of the NC dispersions in water and a variety of organic solvents. Regulation of the Si NCs size is achieved by variation of the surfactants and addition rates, resulting high quality NCs with standard deviations (σ = Δd/d) of less than 10 %. Large scale production of highly mondisperse Si NC was also successfully demonstrated. In chapter 3, a simple solution phase synthesis of size monodisperse carbon quantum dots (CQDs) using a room temperature microemulsion strategy is demonstrated. The CQDs are synthesized in reverse micelles via the reduction of carbon tetrachloride using a hydride reducing agent. CQDs may be functionalised with covalently attached alkyl or amine monolayers, rendering the CQDs dispersible in wide range of polar or non-polar solvents. Regulation of the CQDs size was achieved by utilizing hydride reducing agents of different strengths. The CQDs possess a high photoluminescence quantum yield in the visible region and exhibit excellent photostability. In chapter 4, a simple and rapid assay for detection of Fe3+ ions was developed, based on quenching of the strong blue-green Si NC photoluminescence. The detection method showed a high selectivity, with only Fe3+ resulting in strong quenching of the fluorescence signal. No quenching of the fluorescence signal was induced by Fe2+ ions, allowing for solution phase discrimination between the same ion in different charge states. The optimised sensor system showed a sensitive detection range from 25- 900 μM and a limit of detection of 20.8 μM

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It is essential in musical performance not only to convey the unique language of the composers but also to approach each composition from the perspective of its style. During the 20th century, diverse musical idioms co-existed, sometimes mixing or fusing, yet retaining recognizable characteristics and thereby remaining distinctive. This dissertation explores myriad examples from Late Romanticism/Post- Romanticism, Naturalism, Neo-Classicism, Nationalism and Impressionism composed during this unusually rich period. In order to explore a broad range of collaborative repertoire and to deepen my knowledge of the styles and performance practices relating to these pieces, I studied and performed the repertoire with pianist Eunae Baik–Kim, clarinetist Jihoon Chang, and singers Joshua Brown and Young Joo Lee. The first program featured Post-Romantic, Neo-Classic and Impressionist two-piano works composed by Debussy, Rachmaninoff, and Stravinsky. Each of the three composers used their own distinctive harmonies, rhythms, melodic inventions, pedaling and figurations. In all of the works, both piano parts were densely interwoven, having equal importance. Lied and operatic aria was the focus of the second recital. Brahms’ Vier Ernste Gesänge Op. 121, Ravel’s Don Quichotte a Dulcineé and Italian, French and German operatic arias were the examples of Post-Romanticism and Nationalism. The representative composers were Verdi, Massenet, Korngold, Leoncavallo, Ravel and Wagner. Despite the fact that all of the repertoire was written in traditional musical forms, the composers’ unique voices mark each work as belonging to a particular genre. The third recital focused on Post-Romantic and Impressionistic music written for clarinet and piano: the Première Rhapsodie by Debussy, the Sonata by Poulenc and Brahms’ Sonata in F minor Op. 120, No. 1. These works, although profoundly different in style, share elements of simplicity, clarity and elegance as well as technical virtuosity, articulation and profound musical depth. The three recitals which comprise this dissertation project were performed at the University of Maryland Gildenhorn Recital Hall on February 27, 2010, October 25, 2010, and January 31, 2011. The recitals were recorded on compact disc and are archived within the Digital Repository at the University of Maryland (DRUM).