964 resultados para LEO 15


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Particulate scattering and backscattering are two quantities that have traditionally been used to quantify in situ particulate concentration. The ratio of the backscattering by particles to total scattering by particles (the particulate backscattering ratio) is weakly dependent on concentration and therefore provides us with information on the characteristics of the particulate material, such as the index of refraction. The index of refraction is an indicator of the bulk particulate composition, as inorganic minerals have high indices of refraction relative to oceanic organic particles such as phytoplankton and detrital material that typically have a high water content. We use measurements collected near the Rutgers University Long-term Ecosystem Observatory in 15 m of water in the Mid-Atlantic Bight to examine application of the backscattering ratio. Using four different instruments, the HOBILabs Hydroscat-6, the WETLabs ac-9 and EcoVSF, and a prototype VSF meter, three estimates of the ratio of the particulate backscattering ratio were obtained and found to compare well. This is remarkable because these are new instruments with large differences in design and calibration. The backscattering ratio is used to map different types of particles in the nearshore region, suggesting that it may act as a tracer of water movement. We find a significant relationship between the backscattering ratio and the ratio of chlorophyll to beam attenuation. This implies that these more traditional measurements may be used to identify when phytoplankton or inorganic particles dominate. In addition, it provides an independent confirmation of the link between the backscattering ratio and the bulk composition of particles.

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O presente estudo subordinado ao tema “A influência da Ansiedade nas Competências dos Alunos da Academia Militar: Estudo de caso dos Exercício Finais - Leão 15”, tem como principal finalidade identificar e quantificar a influência da ansiedade nas competências de liderança dos Cadetes-Alunos da Academia Militar. Contribuindo assim, para o reconhecimento das competências influenciadas pela ansiedade e a sua perceção no desempenho, mais propriamente na Informação Comportamental do Aluno. No estudo foi implementado um inquérito constituído por algumas questões de caráter sociodemográfico, um questionário de competências de liderança e um questionário de medição de ansiedade – STAI. Foi aplicado a um grupo de 165 Cadetes-Alunos da Academia, sendo 95 do 4º Ano Escolar e 80 do 1º Ano Escolar. De salientar que este inquérito foi realizado duas vezes: antes e depois do Exercício Leão 15. Com base nas respostas dadas, criou-se uma base de dados em Microsoft Excel, à qual se acrescentaram as notas de Informação Comportamental dos Aluno, e procedeu-se ao seu tratamento e análise estatística, com recurso ao Statistical Package for Social Sciences. (SPSS) Dos resultados obtidos identificaram-se várias diferenças significativas entre os níveis de ansiedade e as competências de liderança, relativamente ao género, ano escolar, curso, ao desporto mais praticado e ao período em análise do Exercício Leão 15 das quais se realçam: o género feminino revelou maior índice de ansiedade no período anterior ao Exercício; o 1ºAno Escolar revelou maior índice de ansiedade estado em ambos os períodos; o curso de EXE-Engenharias revelou maior ansiedade estado e ansiedade traço no período antes do Exercício e os alunos que praticam mais frequentemente desporto coletivo revelam maior Ansiedade Estado no período depois do Exercício Leão 15. Assinalaram-se ainda correlações significativas entre a ansiedade, as competências de liderança e a nota da Informação Comportamental dos Aluno com valores mais elevados nas seguintes: “trabalho de equipa e coesão”; “flexibilidade e adaptabilidade”; “autocontrolo” e “influência e referência”. Com o objetivo de procurar identificar e quantificar as competências mais influenciadas pela ansiedade, concluiu-se que as médias de ansiedade como variável preditora é maior nas competências: “flexibilidade e adaptabilidade”, “capacidade de resolver problemas”, “reconhecimento, feedback positivo e valorização”, “aptidão técnico profissional”, “gestão de conflitos e negociação”, “transparência”, “comunicação assertiva”, “comunicação” e “relações interpessoais”.

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2009

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In order to obtain a biofuel similar to mineral diesel, lanthanum-incorporated SBA- 15 nanostructured materials, LaSBA-15(pH), with different Si/La molar ratios (75, 50, 25), were synthesized in a two-steps hydrothermal procedure, with pH-adjusting of the synthesis gel at 6, and were used like catalytic solids in the buriti oil thermal catalytic cracking. These solids were characterized by X-ray fluorescence (XRF), powder X-ray diffraction (XRD), thermogravimetric analysis (TG/DTG), infrared spectroscopy (FTIR), nitrogen porosimetry and ethanol dehydration, aiming to active sites identify. Taken together, the analyses indicated that the synthesis method has employed to obtain materials highly ordered mesostructures with large average pore sizes and high surface area, besides suggested that the lanthanum was incorporated in the SBA-15 both into the framework as well as within the mesopores. Catalytic dehydration of ethanol over the LaSBA-15(pH) products has shown that they have weak Lewis acid and basic functionalities, indicative of the presence of lanthanum oxide in these samples, especially on the La75SBA-15(pH) sample, which has presented the highest selectivity to ethylene. The buriti oil thermal and thermal catalytic cracking, realized from the room temperature to 450 ºC in a simple distillation system, has allowed obtaining two liquid fractions, each consisting of two phases, one aqueous and another organic, organic liquid (OL). The OL obtained from first fractions has shown high acid index, even in the thermal catalytic process. One the other hand, OL coming from second ones, called green diesel (GD), have presented low acid index, particularly that one obtained from the thermal catalytic process realized over LaSBA-15(pH) samples. The acid sites presence in these samples, associated to their large average pore sizes and high surface areas, have allowed them, especially the La75SBA-15(pH), to present deoxygenating activity in the buriti oil thermal catalytic cracking, providing an oxygenates content reduction, particularly carboxylic acids, in the GD. Furthermore, the GD comes from the second liquid fraction obtained in the buriti oil thermal catalytic cracking over this latest solid sample has shown hydrocarbons composition and physic-chemical properties similar to that mineral diesel, beyond sulfur content low

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113 Briefe zwischen Max Horkheimer und Leo Löwenthal; 1 Brief von Leo Löwenthal an Moritz Horkheimer, 25.08.1942; 1 Brief von Leo Löwenthal an Alfredo Mendizabel, 19.08.1942; 1 Brief von Eileen A. Fry an Max Horkheimer, 19.08.1942; 4 Briefe zwischen Leo Löwenthal und Frederick Pollock, 1942; 1 Brief von Max Horkheimer an Frederick Pollock, 11.12.1942;

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113 Briefe zwischen Max Horkheimer und Leo Löwenthal; 3 Briefe von Max Horkheimer an Franz Neumann, 1942; 1 Brief von Felix Weil an Leo Löwenthal, 08.10.1942; 1 Brief von Max Horkheimer an Paul Tillich, 12.08.1942; 1 Brief von Leo Löwenthal an Margot von Mendelssohn, 10.07.1942; 1 Brief von Ralph O. Nafziger an Leo Löwenthal, 09.06.1942; 1 Rundschreiben vom Forest Lawn Memorial Park (Glendale), 27.05.1942; 1 Brief von Arthur O. Lovejoy an Leo Löwenthal;

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Stimulus encouraging the production and consumption of biodiesel favors the policy of pre-serving the environment, contributing to the reduction of greenhouse gas reducing climate change. The current trend of research in this field focuses on improving these processes with the use of heterogeneous catalysts, seeing has significant advantages such as: low contamination of products, ease of separation of the catalyst from the reaction medium, possibili-ty of reuse of the catalyst, decreased corrosion problems. The objective of this research was to optimize the synthesis of AlSBA-15 for the production of biodiesel through transesterification process via ethyl route. For the optimization of hydrothermal synthesis of type AlSBA-15 catalyst has assembled a 23 factorial experimental matrix with eleven trials. The stoichiometric amounts of starting materials were varied according to different ratios Si / Al which is a factor in the experimental design, in addition to the time and temperature of aging of the synthesis gel. The material showed the best results of characterization (SBET = 591.7 (m2 / g), Vp = 0.83 (cm3 / g), Dp = 5.59 (nm), w = 6.48 (nm) was synthesized at 100 ° C for 24 hours, with a ratio Si / Al = 10.This material was applied as a heterogeneous catalyst in the reaction of ethyl transesterification as raw coconut oil in natura. Coconut oil presented suitable for obtaining biodiesel via ethyl route.The visual aspects and physical-chemical characteristics of the reaction products show that AlSBA-15 catalyst favored the reaction. According to physical-chemical analysis the order of oxidative stability of the product of the transesterification reaction was: catalytic reaction at 1500 ° C> non-catalytic reaction at 100 ° C> 100 ° C catalytic> catalytic reaction at 200 ° C Reaction. The results of oxidative stability and kinematic viscosity shows that the biodiesel produced in the catalytic sandblasting held at 150 ° C which was maintained within the ABNT NBR 7148, ABNT NBR 10441 and EN 14112.

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Center May 2000

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"Dr. Leo Baeck Im Jahre 1900 als junger Rabbiner in Oppeln O.S."