995 resultados para 7140-321
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This study investigates the landscape evolution and soil development in the loess area near Regensburg between approximately 6000-2000 yr BP (radiocarbon years), Eastern Bavaria. The focus is on the question how man and climate influenced landscape evolution and what their relative significance was. The theoretical background concerning the factors that controlled prehistoric soil erosion in Middle Europe is summarized with respect to rainfall intensity and distribution, pedogenesis, Pleistocene relief, and prehistoric farming. Colluvial deposits , flood loams, and soils were studied at ten different and representative sites that served as archives of their respective palaeoenvironments. Geomorphological, sedimentological, and pedological methods were applied. According to the findings presented here, there was a high asynchronity of landscape evolution in the investigation area, which was due to prehistoric land-use patterns. Prehistoric land use and settlement caused highly difIerenciated phases of morphodynamic activity and stability in time and space. These are documented at the single catenas ofeach site. In general, Pleistocene relief was substantially lowered. At the same time smaller landforms such as dells and minor asymmetric valleys filled up and strongly transformed. However, there were short phases at many sites, forming short lived linear erosion features ('Runsen'), resulting from exceptional rainfalls. These forms are results of single events without showing regional trends. Generally, the onset of the sedimentation of colluvial deposits took place much earlier (usually 3500 yr BP (radiocarbon) and younger) than the formation of flood loams. Thus, the deposition of flood loams in the Kleine Laaber river valley started mainly as a consequence of iron age farming only at around 2500 yr BP (radiocarbon). A cascade system explains the different ages of colluvial deposits and flood loams: as a result of prehistoric land use, dells and other minor Pleistocene landforms were filled with colluvial sediments. After the filling of these primary sediment traps , eroded material was transported into flood plains, thus forming flood loams. But at the moment we cannot quantify the extent ofprehistoric soil erosion in the investigation area. The three factors that controlled the prehistoric Iandscapc evolution in the Ioess area near Regensburg are as follows: 1. The transformation from a natural to a prehistoric cultural landscape was the most important factor: A landscape with stable relief was changed into a highly morphodynamic one with soil erosion as the dominant process of this change. 2. The sediment traps of the pre-anthropogenic relief determined where the material originated from soil erosion was deposited: either sedimentation took place on the slopes or the filled sediment traps of the slopes rendered flood loam formation possible. Climatic influence of any importance can only be documented as the result of land use in connection with singular and/or statistic events of heavy rainfalls. Without human impact, no significant change in the Holocene landscape would have been possible.
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The effect of Cl- on the corrosive wear behaviour of AISI 321 stainless steel in H2SO4 solution was studied via the corrosive wear rate, the load bearing capacity of passive film and the relationship between pitting and corrosive wear. There is a critical load at natural potential, below which the corrosive wear rate is slightly lowered by Cl-, while above which is increased. At natural potential there are more pits at low load than that at a higher one in the wear tracks and the pits are also deeper. The load bearing capacity is lowered by Cl- at passive region and then the corrosive wear rate increased.
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The stress corrosion cracking (SCC) of LambdaISI 321 stainless steel in acidic chloride solution was studied by slow strain rate (SSR) technique and fracture mechanics method. The fractured surface was characterized by cleavage fracture. In order to clarify the SCC mechanism, the effects of inhibitor KI on SCC behaviour were also included in this paper. A study showed that the inhibition effects of KI on SCC were mainly attributed to the anodic reaction of the corrosion process. The results of strain distribution in front of the crack tip of the fatigue pre-cracked plate specimens in air, in the blank solution (acidic chloride solution without inhibitor KI) and in the solution added with KI measured by speckle interferometry (SPI) support the unified mechanism of SCC and corrosion fatigue cracking (CFC).
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Collection : Théâtre contemporain illustré ; 321e et 322e livraisons
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Tesis (Maestría en Ciencias de la Ingeniería Mecánica con Especialidad en Materiales) UANL, 2013.
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Este estudio, a través de una revisión integradora de la literatura científica, analiza cómo las prácticas de atención de la salud mental incluyen la dimensión de la ciudadanía, basada en el fortalecimiento y/o construcción de su ejercicio. El trabajo trata sobre el panorama actual de las nuevas prácticas de cuidado en salud mental, desarrolladas desde el paradigma psicosocial, con base en las propuestas de la reforma psiquiátrica brasileña. Para tal fin, se analizaron los artículos brasileños publicados en las bases de datos Lilacs/ BVS y Scielo, en el período de 2002 a 2011, que presentaran experiencias de actividades de cuidado en salud mental en el ámbito del Sistema Único de Salud, respecto a la forma como son desarrolladas, sus avances y desafíos. Los resultados indican que en la actualidad, una gran variedad de nuevas prácticas se desarrolla en diferentes servicios por parte de equipos multidisciplinarios y que éstas traen innovaciones importantes en el quehacer frente a la demencia. Sin embargo, todavía está presente el modelo del manicomio, expresado de una nueva manera y desarrollado por los nuevos servicios. Asimismo, hay discontinuidad en las prácticas y falta de financiamiento para el desarrollo de actividades innovadoras
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Incluye cuatro tipos de índices que facilitan la búsqueda de los artículos publicados en los números 321 a 323 y en el número extraordinario del año 2000. En el primer índice, los artículos se agrupan por notaciones de la Clasificación Decimal Universal (CDU) y en los siguientes por orden alfabético de autores, títulos y materias.
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Jornal elaborado pela Assessoria de Comunicação e Imprensa da Reitoria da UNESP