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91.
For nearly a decade the La Paz-El Alto concession in Bolivia was heralded by donor organizations, the state and the commercial water industry alike as an emblematic ‘pro-poor’ water concession under the private sector model. Managed by one of the largest water multinationals in the world (the French company Suez), the network was extended beyond the new connections required by the original ‘pro-poor’ contract, acclaimed as a pioneer of new pro-poor technologies and frequently disseminated internationally as an example of best practice. This paper analyses the La Paz-El Alto concession’s pro-poor image focusing on issues of social exclusion and network extension, contract negotiation, participation and transparency. It documents the rise of social protest about the concession and critiques the failure of neoliberal regulatory systems to promote accountability to the poor. In the context of the continued transnationalisation of the water industry the paper highlights the need for new mechanisms and delivery models to ensure greater national control over private companies and the development of a framework for international water governance. 相似文献
92.
Aloísio J.B. Cotta Jacinta Enzweiler Stephen A. Wilson Carlos A. Pérez Antonio J.R. Nardy João H. Larizzatti 《Geostandards and Geoanalytical Research》2007,31(4):379-393
Reference materials (RM) are required for quantitative analyses and their successful use is associated with the degree of homogeneity, and the traceability and confidence limits of the values established by characterisation. During the production of a RM, the chemical characterisation can only commence after it has been demonstrated that the material has the required level of homogeneity. Here we describe the preparation of BRP-1, a proposed geochemical reference material, and the results of the tests to evaluate its degree of homogeneity between and within bottles. BRP-1 is the first of two geochemical RM being produced by Brazilian institutions in collaboration with the United States Geological Survey (USGS) and the International Association of Geoanalysts (IAG). Two test portions of twenty bottles of BRP-1 were analysed by wavelength dispersive-XRF spectrometry and major, minor and eighteen trace elements were determined. The results show that for most of the investigated elements, the units of BRP-1 were homogeneous at conditions approximately three times more rigorous than those strived for by the test of "sufficient homogeneity". Furthermore, the within bottle homogeneity of BRP-1 was evaluated using small beam (1 mm2 ) synchrotron radiation XRF spectrometry and, for comparison, the USGS reference materials BCR-2 and GSP-2 were also evaluated. From our data, it has been possible to assign representative minimum masses for some major constituents (1 mg) and for some trace elements (1-13 mg), except Zr in GSP-2, for which test portions of 74 mg are recommended. 相似文献
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94.
Mock 2dF and SDSS galaxy redshift surveys 总被引:1,自引:0,他引:1
95.
Carlos Schubert 《International Journal of Earth Sciences》1981,70(2):542-551
Three major fault systems have been recognized in Venezuela: the Oca, Boconó, and El Pilar fault zones. The Boconó-El Pilar system is an active, Late Pleistocene-Holocene fault system, which extends for over 1300 km between the Venezuela-Colombia border, through the Venezuelan Andes and along the northern Venezuelan coast, to the east of Trinidad. Recent tectonic evidence suggests that until the Late Tertiary or Early Quaternary, the Caribbean Plate-South America Plate boundary included the El Pilar and Oca fault systems. Since then, it has included the Boconó fault system. Right-lateral offset along these fault systems is not sufficient to derive the Caribbean Plate from Pacific crust; alternatively, the Caribbean Plate may have been a part of the South America Plate until comparatively recent geologic-time.
Dedicated to the memory of John D. Weaver. 相似文献
Zusammenfassung Drei wichtige Bruchsysteme sind in Venezuela festgestellt worden: die Oca, Boconé und El Pilar Bruchzonen. Das Boconó-El-Pilar-System ist ein aktives, Spätpleistozänes-Holozänes System, daß sich über mehr als 1300 km erstreckt, von der venezolanischkolumbianischen Grenze, durch die venezolanischen Anden und längs der nördlichen venezolanischen Küste, bis östlich von Trinidad. Rezente tektonische Daten lassen andeuten, daß bis zum Spättertiär oder Frühquartär, die Grenze zwischen der Karibischen Platte und der Südamerika-Platte die El Pilar- und Oca-Bruchsysteme einschloß. Später hat sie das Boconó-Bruchsystem eingeschlossen. Rechtsinnige Blattverschiebung an diesen Bruchsystemen ist nicht groß genug, um die Karibische Platte als ein Stück pazifischer Kruste zu betrachten; oder aber, die Karibische Platte war mit der Südamerika-Platte vereinigt bis zu einem relativ jungen geologischen Alter.
Resumen Se han establecido tres sistemas mayores de fallamiento en Venezuela: las zonas de falla de Oca, Boconó y El Pilar. El sistema de Boconó-El Pilar es un sistema de falla activo pleistoceno-holoceno, el cual se extiende por más de 1300 km entre la frontera colombo-venezolana, a traves de los Andes venezolanos y a lo largo de la costa norte de Venezuela, hasta más al este de Trinidad. Evidencias tectónicas recientes sugieren que hasta el Terciario Tardio o Cuatemario Temprano, el límite entre las Plaças del Caribe y de América del Sur incluía los sistemas de falla de Oca y El Pilar. Desde entonces incluye al sistema de falla de Boconó. El desplazamiento de rumbo hacia la derecha a lo largo de estos sistemas de fallamiento no es suficiente para derivar la Plaça del Caribe de la corteza pacifica; alternativamente, la Placa del Caribe puede haber sido parte de la Placa de América del Sur hasta una época geológica relativamente reciente.
: , ' El Pilar. - / , 1300 - , . , 1 Pilar. '. , , , , , .
Dedicated to the memory of John D. Weaver. 相似文献
96.
Late Pleistocene glacial features in the Páramo de La Culata region, north-central Venezuelan Andes, include: 1. depositional features: morainic till and fluvio-glacial deposits (terrace gravels); 2. sculptured features: glaciated valleys, cirques, horns, and arêtes; and 3. erosional features: striation and grooving, polished rock, roches moutonnées and whaleback forms, and erratic boulders. Two main levels of moraines were found, an older one at 2600 m elevation, and a younger one between 3000 and 3500 m. The difference in age is reflected by the higher degree of weathering, erosion, and vegetation cover of the lower level, as compared with the higher level. Radiocarbon dating, and a comparison and correlation of these glacial features with those of adjacent regions, indicates that the lower morainic level (2600 m) is probably the result of the main glacial advance of the Late Wisconsin Glaciation. The main morainic level (3000 to 3500 m) was probably formed by the latest Wisconsin glacial advance. The Late Pleistocene snow-line depression reached approximately 1200 m below the present snow-line (i. e., down to approximately 3500 m). 相似文献
97.
Carlos A.E De Albuquerque 《Geochimica et cosmochimica acta》1974,38(5):789-803
Chemical analyses are given for actinolitic hornblendes of tonalitic rocks from the Hercynian belt of Northern Portugal. The distribution of elements between amphibole and co-existing biotite is studied. The composition of the amphiboles is analysed in the light of experimental data on amphiboles and the physical conditions of crystallization inferred from the study of the biotite and rock series. The data on the biotites lead to the definition of a temperature of 800°C for the crystallization of actinolitic hornblendes with Mg/(Mg + Fe) ratios of 0·72-0·61 at pressures of about 3 Kb and fO2 defined by FMQ. 相似文献
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