969 resultados para country rock instantaneous point source solld-llquid interface


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The multicomponent nonideal gas lattice Boltzmann model by Shan and Chen (S-C) is used to study the immiscible displacement in a sinusoidal tube. The movement of interface and the contact point (contact line in three-dimension) is studied. Due to the roughness of the boundary, the contact point shows "stick-slip" mechanics. The "stick-slip" effect decreases as the speed of the interface increases. For fluids that are nonwetting, the interface is almost perpendicular to the boundaries at most time, although its shapes at different position of the tube are rather different. When the tube becomes narrow, the interface turns a complex curves rather than remains simple menisci. The velocity is found to vary considerably between the neighbor nodes close to the contact point, consistent with the experimental observation that the velocity is multi-values on the contact line. Finally, the effect of three boundary conditions is discussed. The average speed is found different for different boundary conditions. The simple bounce-back rule makes the contact point move fastest. Both the simple bounce-back and the no-slip bounce-back rules are more sensitive to the roughness of the boundary in comparison with the half-way bounce-back rule. The simulation results suggest that the S-C model may be a promising tool in simulating the displacement behaviour of two immiscible fluids in complex geometry.

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A dissertação aqui apresentada versa sobre uma temática nova, quer vista sob a ótica do nascimento do fato sociológico analisado - O Sindicalismo e a Administração Pública quer se considere a quase inexistência de fontes nas quais se possa abeberar, para que fosse possível estabelecer o fio condutor no desenvolvimento do tema. A temática foi analisada em dois planos: primeiro, fêz-se uma apreciação crítica da história do associativismo no Brasil, em sua simbiose com o aspecto social, com o lado econômico e com o lastro jurídico, ao ser analisado o caminho percorrido desde o primeiro clarão do Brasil até os dias presentes. Em segundo estágio, perquiriu-se a questão sindical, no que diz respeito à sua etiologia, o seu despertar mais consciente na década de 80 do nosso século, perpassando pela criação das Centrais Sindicais, ao serem detectados os desvios ideológicos, as contradições, a sua fisiologia em função de sua organização, ideário e ação na direção do que se propõem em nome de seus afiliados. Com efeito, o núcleo do trabalho se cinge à arregimentação do corpo de funcionários públicos com vistas a um eficaz - hoje, ainda muito incipiente - congraçamento, ao se deparar com uma forte resistência institucional, de vez que só a partir da Constituição de 1988, é que se abriu caminho para o direito de associação sindical a esse estamento dos agentes públicos. As disfunções são, aí, analisadas em relação ao despreparo dos Recursos Humanos no exercício de liderança e em confronto com a estrutura institucional anacrônica e de feitio autoritário, para fazer valer, de forma eficaz e efetiva, um bom desempenho da ação sindical, que se deseja genuína, autônoma e autógena, em função dos interesses de classe e a ter em vista a excelência dos serviços públicos; o fenômeno estudado, inversamente, mostra o processamento de uma luta sindical radicada em estrutura antidemocrática, em que o Estado financia os sindicatos e todo o aparelhamento sindical vertical, via contribuição sindical e a considerar que esse lastro sustentador da luta sindical é decalque de uma época de predominância de valores chauvinistas, exaltados no Brasil - e em outros países -, nas décadas de 30 e 40. Ainda foi feito um estudo comparativo com três modelos de sindicalismo, quais sejam: o francês, o alemão e o português. Os dois primeiros por razões de se constituirem em paradigmas de países centrais, tendo em vista que: (1) a França é modelo inspirador das instituições ocidentais, em sede político-jurídico-social, haja vista a sua História prenhe de fatos solapadores do statu quo ante; e (2) a Alemanha, por ter uma classe eficazmente institucionalizada de agentes públicos, tendo tradição araigada desde a burocracia prussiana, o que dá o toque de elevado profissionalismo a esses agentes públicos, os quais contam com uma agremiação sindical que guarda independência com relação ao movimento sindical do trabalhador privado, este, também consolidado em poderosa organização sindical naquele país. Portugal aparece no trabalho como o ascendente cultural do Brasil, o que implica em ser mostrado o nascedouro sindical desse país, dentro do clima cultural em que viveu e vive a península lusitana, e com isso se tenta elucidar o estágio de seu sindicalismo, as suas disfunções e auto funções , as suas semelhanças com o modelo brasileiro, as suas inclinações e natureza. As conclusões aferidas registram alguns aspectos relevantes: 1º) o Brasil nasceu de uma Administração centralizadora, marcada por uma máquina administrativa ineficaz, ineficiente, com a marca do Estato-império e sem a presença da construção concomitante de uma nação que é retardatária no assentar a viga da cidadania, o que levou a delongar a formação dos anseios e do espírito genuinamente autóctones. A repressão ao desenvolvimento das letras foi um entrave à criação de um espírito de povo, com a variante de ser uma maioria inculta, massacrantemente iletrada, em meio a uma pirâmide social em que se registrava apenas uma base desmesurada e um vértice acanhado, sem ter de permeio outras classes sociais que pudessem ser ou vir a ser estratificadas. Na esteira desses elementos, concluiu-se que: 2º) o movimento associativo é uma realidade incipiente e adormecido durante séculos, o que desbordou em uma apatia que só hoje começa a ser sacudida, através dos movimentos associativistas e sindical, este último nascido no meio das fábricas e estendido a algumas capitais de maior relevância política ou de maior peso econômico. o aspecto de maior magnitude para o trabalho foi a sinalização aberta aos servidores públicos para que se sindicalizassem, do que decorreu a conclusão de que essa ação precisa ser tangenciada e carreada a ser um movimento mais autenticamente ligado aos interesses da classe, pois por desvirtuamento contingencial em face da iniciante pouca expressão e inexperiência desse estamento, a ação sindical desses servidores sempre esteve à ilharga do movimento sindical do trabalhador privado, o qual tem outra linha de ação direcionada a interesses mais ligados ao conflito trabalho vs. capital, interesses esses que não se coadunam e nem se identificam com as aspirações e necessidades do funcionalismo público, mesmo que, muitas vezes, a questão do conflito desses agentes tenha uma interface no conjunto da pauta de reivindicação dos trabalhadores privados, ou seja, a questão salarial. O imperativo maior - e esta é a base da recomendação mais substancial - é conduzir a ação dos agentes públicos de forma heterodoxa na direção de se independentizar o movimento sindical desses agentes, a ser impulsionado pelas suas peculiaridades e por sua essencialidade ditada pela sua ontologia de servidores da coisa pública e tendo o público como sua clientela. Este é, em síntese, o caminho aqui trilhado.

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The Brasiliano Cycle in the Seridó Belt (NE Brazil) is regarded mostly as a crustal reworking event, characterized by transcurrent or transpressional shear zones which operated under high temperature and low pressure conditions. In the eastern domain of this belt- the so-called São José de Campestre Massif (SJCM), a transtensional deformation regime is evidenced by extensional components or structures associated to the strikeslip shear zones. The emplacement of the Neoproterozoic Brasiliano granitoids is strongly controled by these discontinuities. Located in the southern border of the SJCM, the Remígio-Pocinhos shear zone (RPSZ) displays, in its northern half, top to the SW extensional movement which progressively grade, towards its southern half, to a dextral strike-slip kinematics, defining a negative semi-flower structure. This shear zone is overprinted upon allocthonous metasediments of the Seridó Group and an older gneiss-migmatite complex, both of which containing metamorphic parageneses from high amphibolite to granulite facies (the latter restricted to the strike-slip zone), defining the peak conditions of deformation. Several granitoid plutons are found along this structure, emplaced coeval with the shearing event. Individually, such bodies do not exceed 30 km2 in outcropping area and are essentially parallel to the trend of the shear zone. Petrographic, textural and geochemical data allow to recognize five different granitoid suites along the RPSZ: porphyritic granites (Serra da Boa Vista and Jandaíra), alkaline granites (Serra do Algodão and Serra do Boqueirão) and medium to coarse-grained granites (Olivedos) as major plutons, while microgranite and aluminous leucogranite sheets occur as minor intrusions. The porphyritic granites are surrounded by metasediments and present sigmoidal or en cornue shapes parallel to the trend of the RPSZ, corroborating the dextral kinematics. Basic to intermediate igneous enclaves are commonly associated to these bodies, frequently displaying mingling textures with the host granitoids. Compositionally these plutons are made up by titanite-biotite monzogranites bearing amphibole and magnetite; they are peraluminous and show affinities to the monzonitic, subalkaline series. Peraluminous, ilmenite-bearing biotite monzogranites and titanite-biotite monzogranites correspond, respectivally, to the Olivedos pluton and the microgranites. The Olivedos body is hosted by metasediments, while the microgranites intrude the gneiss-migmatite complex. Being highly evolved rocks, samples from these granites plot in the crustal melt fields in discrimination diagrams. Nevertheless, their subtle alignment also looks consistent with a monzonitic, subalkaline affinity. These chemical parameters make them closer to the I-type granites. Alkaline, clearly syntectonic granites are also recognized along the RPSZ. The Serra do Algodão and Serra do Boqueirão bodies display elongated shapes parallel to the mylonite belt which runs between the northern, extensional domain and the southern strike-slip zone. The Serra do Algodão pluton shows a characteristic isoclinal fold shape structure. Compositionally they encompass aegirine-augite alkali-feldspar granites and quartz-bearing alkaline syenite bearing garnet (andradite) and magnetite plus ilmenite as opaque phases. These rocks vary from meta to peraluminous, being correlated to the A-type granites. Aluminous leucogranites bearing biotite + muscovite ± sillimanite ± garnet (S-type granites) are frequent but not volumetrically important along the RPSZ. These sheet-like bodies may be folded or boudinaged, representing partial melts extracted from the metasediments during the shear zone development. Whole-rock Rb-Sr isotope studies point to a minimum 554��10 Ma age for the crystalization of the porphyritic granites. The alkaline granites and the Olivedos granite produced ca. 530 Ma isochrons which look too young; such values probably represent the closure of the Rb-Sr radiometric clock after crystallization and deformation of the plutons, at least 575 Ma ago (Souza et al. 1998). The porphyritic and the alkaline granites crystallized under high oxygen fugacity conditions, as shown by the presence of both magnetite and hematite in these rocks. The presence of ilmenite in the Olivedos pluton suggests less oxidizing conditions. Amphibole and amphibole-plagioclase thermobarometers point to minimum conditions, around 750°C and 6 Kbars, for the crystallization of the porphyritic granites. The zirconium geothermometer indicates higher temperatures, in the order of 800°C, for the porphyritic granites, and 780°C for the Olivedos pluton. Such values agree with the thermobarometric data optained for the country rocks (5,7 Kbar and 765°C; Souza et al. 1998). The geochemical and isotope data set point to a lower crustal source for the porphyritic and the alkaline granites. Granulite facies quartz diorite to tonalite gneisses, belonging or akin to the gneiss-migmatite complex, probably dominate in the source regions. In the case of the alkaline rocks, subordinate contributions of mantle material may be present either as a mixing magma or as a previously added component to the source region. Tonalite to granodiorite gneisses, with some metasedimentary contribution, may be envisaged for the Olivedos granite. The diversity of granitoid rocks along the RPSZ is explained by its lithospheric dimension, allowing magma extraction at different levels, from the middle to lower crust down to the mantle. The presence of basic to intermediate enclaves, associated to the porphyritic granites, confirm the participation of mantle components in the magma extraction system along the RPSZ. This mega-structure is part of the network of Brasiliano-age shear zones, activated by continental collision and terrane welding processes at the end of the Neoproterozoic

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The NNW-trending Nova Lacerda tholeiitic dike swarm in Mato Grosso State, Central Brazil, intrudes the Nova Lacerda granite (1.46 Ga) and the Jauru granite-greenstone terrain (ca. 1.79-1.77 Ga). The swarm comprises diabases I and II and amphibolites emplaced at ca. 1.38 Ga. Geochemical data indicate that these are evolved tholeiites characterized by high LILE/HSFE and LREE/HSFE ratios. Isotopic modelling yields positive epsilon(Nd)(T) values (+0.86 to +2.65), whereas values for epsilon(Sr)(T) range from positive to negative (+1.96 to -5.56). Crustal contamination did not play a significant petrogenetic role, as indicated by a comparison of isotopic data (Sr-Nd) from both dikes and country rocks, and by the relationship between isotopic and geochemical parameters (SiO2, K2O, Rb/Sr, and La/Yb) of the dikes. We attribute the origin of these tholeiites to fractional crystallization of evolved melts derived from a heterogeneous mantle source. Comparison of the geochemical and isotopic data of the studied swarm and other tholeiitic Mesoproterozoic mafic intrusions of the SWAmazonian Craton the Serra da Providencia, Colorado, and Nova Brasilandia bimodal suites - indicates that parental melts of the Nova Lacerda swarm were derived from the most enriched mantle source. This enrichment was probably caused by the stronger influence of the EMI component on the DMM end-member. These data, coupled with trace element bulk-rock geochemistry of the country rocks, and comparisons with the Colorado Complex of similar age, suggest a continental-margin arc setting for the emplacement of the Nova Lacerda dikes.

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Analysts, politicians and international players from all over the world look at China as one of the most powerful countries on the international scenario, and as a country whose economic development can significantly impact on the economies of the rest of the world. However many aspects of this country have still to be investigated. First the still fundamental role played by Chinese rural areas for the general development of the country from a political, economic and social point of view. In particular, the way in which the rural areas have influenced the social stability of the whole country has been widely discussed due to their strict relationship with the urban areas where most people from the countryside emigrate searching for a job and a better life. In recent years many studies have mostly focused on the urbanization phenomenon with little interest in the living conditions in rural areas and in the deep changes which have occurred in some, mainly agricultural provinces. An analysis of the level of infrastructure is one of the main aspects which highlights the principal differences in terms of living conditions between rural and urban areas. In this thesis, I first carried out the analysis through the multivariate statistics approach (Principal Component Analysis and Cluster Analysis) in order to define the new map of rural areas based on the analysis of living conditions. In the second part I elaborated an index (Living Conditions Index) through the Fuzzy Expert/Inference System. Finally I compared this index (LCI) to the results obtained from the cluster analysis drawing geographic maps. The data source is the second national agricultural census of China carried out in 2006. In particular, I analysed the data refer to villages but aggregated at province level.

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Today, crude oil remains a vital resource all around the world. This non-renewable resource powers countries worldwide. Besides serving as an energy source, crude oil is also the most important component for different world economies, especially in developing countries. Ecuador, a small member of the OPEC oil cartel, presents a case where its economy is oil dependent. A great percentage of the countryÿs GDP and governmentÿs budget comes from oil revenues. Ecuador has always been a primary exporter of raw materials. In the last centuries, the country experienced three important economic booms: cacao, bananas, and, ultimately, crude oil. In this sense, the country has not been able to fully industrialize and begin to export manufactured goods, i.e., Ecuador suffers from the Dutch disease. The latter has deterred Ecuador from achieving broad-based economic development. Given crude oilÿs importance for the Ecuadorian economy, the government has always tried to influence the oil industry in search of profits and benefits. Therefore, this thesis, explores the question: how and to what extent have political interventions affected the oil industry in Ecuador from 1990 until March 2014? In general, this thesis establishes an economic history context during the last twenty-four years, attempting to research how political interventions have shaped Ecuadorÿs oil industry and economy. In the analysis, it covers a period where political instability prevailed, until Rafael Correa became president. The thesis examines Ecuadorÿs participation in OPEC, trying to find explanations as to why the country voluntarily left the organization in 1992, only to rejoin in 2007 when Correa rose to power. During the ÿRevolución Ciudadanaÿ period, the thesis researches reforms to the Law of Hydrocarbons, variations in the relations with other nations, the controversy surrounding the Yasuní-ITT oil block, and the ÿRefinería del Pacíficoÿ construction. The thesis is an Industrial Organization detailed case study that analyzes, updates, and evaluates the intersection of economics and politics in Ecuadorÿs crude oil industry during the last 24 years. In this sense I have consulted past theses, newspaper articles, books, and other published data about the petroleum industry, both from a global and Ecuadorian perspective. In addition to published sources, I was able to interview sociologists, public figures, history and economics academics, and other experts, accessing unique unpublished data about Ecuadorÿs oil industry. I made an effort to collect information that shows the private and public side of the industry, i.e., from government-related and independent sources. I attempted to remain as objective as possible to make conclusions about the appropriate Industrial Organization policy for Ecuadorÿs oil industry, addressing the issue from an economic, social, political, and environmental point of view. I found how Ecuadorÿs political instability caused public policy to fail, molding the conduct and market structure of the crude oil industry. Throughout history, developed nations have benefited from low oil prices, but things shifted since oil prices began to rise, which is more beneficial for the developing nations that actually possess and produce the raw material. Nevertheless, Ecuador, a victim of the Dutch disease due to its heavy reliance on crude oil as a primary product, has not achieved broad-based development.

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Ensuring water is safe at source and point-of-use is important in areas of the world where drinking water is collected from communal supplies. This report describes a study in rural Mali to determine the appropriateness of assumptions common among development organizations that drinking water will remain safe at point-of-use if collected from a safe (improved) source. Water was collected from ten sources (borehole wells with hand pumps, and hand-dug wells) and forty-five households using water from each source type. Water quality was evaluated seasonally (quarterly) for levels of total coliform, E.coli, and turbidity. Microbial testing was done using the 3M Petrifilm⢠method. Turbidity testing was done using a turbidity tube. Microbial testing results were analyzed using statistical tests including Kruskal-Wallis, Mann Whitney, and analysis of variance. Results show that water from hand pumps did not contain total coliform or E.coli and had turbidity under 5 NTUs, whereas water from dug wells had high levels of bacteria and turbidity. However water at point-of-use (household) from hand pumps showed microbial contamination - at times being indistinguishable from households using dug wells - indicating a decline in water quality from source to point-of-use. Chemical treatment at point-of-use is suggested as an appropriate solution to eliminating any post-source contamination. Additionally, it is recommended that future work be done to modify existing water development strategies to consider water quality at point-of-use.

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In 2010 more than 600 radiocarbon samples were measured with the gas ion source at the MIni CArbon DAting System (MICADAS) at ETH Zurich and the number of measurements is rising quickly. While most samples contain less than 50 mu g C at present, the gas ion source is attractive as well for larger samples because the time-consuming graphitization is omitted. Additionally, modern samples are now measured down to 5 per-mill counting statistics in less than 30 min with the recently improved gas ion source. In the versatile gas handling system, a stepping-motor-driven syringe presses a mixture of helium and sample CO2 into the gas ion source, allowing continuous and stable measurements of different kinds of samples. CO2 can be provided in four different ways to the versatile gas interface. As a primary method. CO2 is delivered in glass or quartz ampoules. In this case, the CO2 is released in an automated ampoule cracker with 8 positions for individual samples. Secondly, OX-1 and blank gas in helium can be provided to the syringe by directly connecting gas bottles to the gas interface at the stage of the cracker. Thirdly, solid samples can be combusted in an elemental analyzer or in a thermo-optical OC/EC aerosol analyzer where the produced CO2 is transferred to the syringe via a zeolite trap for gas concentration. As a fourth method, CO2 is released from carbonates with phosphoric acid in septum-sealed vials and loaded onto the same trap used for the elemental analyzer. All four methods allow complete automation of the measurement, even though minor user input is presently still required. Details on the setup, versatility and applications of the gas handling system are given. (C) 2012 Elsevier B.V. All rights reserved.

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The sedimentary archive from Laguna Potrok Aike is the only continuous record reaching back to the last Glacial period in continental southeastern Patagonia. Located in the path of the Southern Hemisphere westerly winds and in the source region of dust deposited in Antarctica during Glacial periods, southern Patagonia is a vantage point to reconstruct past changes in aeolian activity. Here we use high-resolution rock-magnetic and physical grain size data from site 2 of the International Continental scientific Drilling Program (ICDP) Potrok Aike maar lake Sediment Archive Drilling prOject (PASADO) in order to develop magnetic proxies of dust and wind intensity at 52°S since 51,200 cal BP. Rock-magnetic analysis indicate the magnetic mineral assemblage is dominated by detrital magnetite. Based on the estimated flux of magnetite to the lake and comparison with distal dust records from the Southern Ocean and Antarctica, kLF is interpreted as a dust indicator in the dust source of southern Patagonia at the millennial time scale, when ferrimagnetic grain size and coercivity influence is minimal. Comparison to physical grain-size data indicates that the median destructive field of isothermal remanent magnetisation (MDFIRM) mostly reflects medium to coarse magnetite bearing silts typically transported by winds for short-term suspension. Comparison with wind-intensity proxies from the Southern Hemisphere during the last Glacial period and with regional records from Patagonia since the last deglaciation including marine, lacustrine and peat bog sediments as well as speleothems reveals similar variability with MDFIRM up to the centennial time scale. MDFIRM is interpreted as a wind-intensity proxy independent of moisture changes for southeastern Patagonia, with stronger winds capable of transporting coarser magnetite bearing silts to the lake.

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The Integrated Ocean Drilling Program Expedition 318 to the Wilkes Land margin of Antarctica recovered a sedimentary succession ranging in age from lower Eocene to the Holocene. Excellent stratigraphic control is key to understanding the timing of paleoceanographic events through critical climate intervals. Drill sites recovered the lower and middle Eocene, nearly the entire Oligocene, the Miocene from about 17 Ma, the entire Pliocene and much of the Pleistocene. The paleomagnetic properties are generally suitable for magnetostratigraphic interpretation, with well-behaved demagnetization diagrams, uniform distribution of declinations, and a clear separation into two inclination modes. Although the sequences were discontinuously recovered with many gaps due to coring, and there are hiatuses from sedimentary and tectonic processes, the magnetostratigraphic patterns are in general readily interpretable. Our interpretations are integrated with the diatom, radiolarian, calcareous nannofossils and dinoflagellate cyst (dinocyst) biostratigraphy. The magnetostratigraphy significantly improves the resolution of the chronostratigraphy, particularly in intervals with poor biostratigraphic control. However, Southern Ocean records with reliable magnetostratigraphies are notably scarce, and the data reported here provide an opportunity for improved calibration of the biostratigraphic records. In particular, we provide a rare magnetostratigraphic calibration for dinocyst biostratigraphy in the Paleogene and a substantially improved diatom calibration for the Pliocene. This paper presents the stratigraphic framework for future paleoceanographic proxy records which are being developed for the Wilkes Land margin cores. It further provides tight constraints on the duration of regional hiatuses inferred from seismic surveys of the region.

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In 2014, UniDive (The University of Queensland Underwater Club) conducted an ecological assessment of the Point Lookout Dive sites for comparison with similar surveys conducted in 2001 - the PLEA project. Involvement in the project was voluntary. Members of UniDive who were marine experts conducted training for other club members who had no, or limited, experience in identifying marine organisms and mapping habitats. Since the 2001 detailed baseline study, no similar seasonal survey has been conducted. The 2014 data is particularly important given that numerous changes have taken place in relation to the management of, and potential impacts on, these reef sites. In 2009, Moreton Bay Marine Park was re-zoned, and Flat Rock was converted to a marine national park zone (Green zone) with no fishing or anchoring. In 2012, four permanent moorings were installed at Flat Rock. Additionally, the entire area was exposed to the potential effects of the 2011 and 2013 Queensland floods, including flood plumes which carried large quantities of sediment into Moreton Bay and surrounding waters. The population of South East Queensland has increased from 2.49 million in 2001 to 3.18 million in 2011 (BITRE, 2013). This rapidly expanding coastal population has increased the frequency and intensity of both commercial and recreational activities around Point Lookout dive sites (EPA 2008). Habitats were mapped using a combination of towed GPS photo transects, aerial photography and expert knowledge. This data provides georeferenced information regarding the major features of each of the Point Lookout Dive Sites.