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231.
Guido G. Weigend 《Geoforum》1973,4(1):5-15
Rotterdam and Antwerp, situated in close proximity to each other, have evolved over the past seven centuries to become the world's largest and Europe's second largest ports respectively. Mainly for political reasons, the stages of rise and decline occurred in complementary time periods, until freedom of inland shipping became international law on the Rhine and in the Rhine-Maas-Schelde delta region in the 19th century. Since then Antwerp's ascendancy has occurred without serious interruption, though areal expansion is now limited by the Belgian-Dutch boundary. Rotterdam, on the other hand, has faced two difficult periods involving ease and speed of access to the North Sea, and destruction during World War II. 相似文献
232.
A. Mottana R. Bocchio R. Crespi L. De Capitani G. Liborio G. Della Ventura 《Mineralogy and Petrology》1994,51(1):67-84
Summary Cummingtonite and hornblende occur together in metamorphosed basic rocks interlayered with lower-amphibolite facies sillimanite-muscovite-bearing schists and gneisses in the upper Lake Como region, South-Alpine basement complex of the Alps. Textural, chemical and spectroscopic studies indicate that they do not represent equilibrium pairs, but that hornblende was overgrown by cummingtonite during a late stage of either temperature increase or, more likely, of isothermal pressure release, by a continuous reaction which also produced the reverse zoning of plagioclase.
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Cummingtonit in den Amphiboliten des südalpinen Grundgebirges (oberes Comosee-Gebiet, Italien): seine Beziehungen mit Hornblende
Zusammenfassung Im Gebiet des oberen Como-Sees, im südalpinen Basement-Komplex, kommen Cummingtonit und Hornblende zusammen in metamorphen, basischen Gesteinen mit Zwischenlagen von Sillimanit-Muskovit-führenden Schiefern und Gneisen der unteren Amphibolit-Fazies vor. Untersuchung der Texturen, der chemischen Zusammensetzung und Infrarot-Spektroskopie zeigen, daß diese nicht Gleichgewichts-Paare darstellen, sondern daß Hornblende während eines späten Stadiums, entweder bei zunehmender Temperatur, oder eher während isothermalen Druck-Nachlasses durch eine kontinuierliche Reaktion von Cummingtonit überwachsen wurde, die auch für die reverse Zonierung der Plagioklase verantwortlich ist.
With 5 Figures 相似文献
233.
Molinari Daniela Dazzi Susanna Gattai Edoardo Minucci Guido Pesaro Giulia Radice Alessio Vacondio Renato 《Natural Hazards》2021,108(3):3061-3084
Natural Hazards - This paper shows a detailed, advanced procedure to implement cost–benefit analyses (CBAs) in order to assess the effectiveness of flood mitigation measures. The town of Lodi... 相似文献
234.
Advanced frame element for seismic analysis of masonry structures: model formulation and validation
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This paper presents a masonry panel model for the nonlinear static and dynamic analysis of masonry buildings suitable for the seismic assessment of new and existing structures. The model is based on an equivalent frame idealization of the structure and stems from previous research on force‐based frame elements. The element formulation considers axial, bending, and shear deformations within the framework of the Timoshenko beam theory. A phenomenological cyclic section law that accounts for the shear panel response is coupled, through equilibrium between shear and bending forces along the element, with a fiber‐section model that accounts for the axial and bending responses. The proposed panel model traces with a low computational burden and numerical stability the main aspects of the structural behavior of masonry panels and is suitable for analyses of multi‐floor buildings with a relatively regular distribution of openings and with walls and floors organized to grant a box‐like behavior under seismic loads. The model capabilities are validated though analyses of simple unreinforced masonry panels and comparisons with published experimental results. The model accuracy is strongly dependent on the fiber and shear constitutive laws used. However, the formulation is general, and laws different from those employed in this study are easily introduced without affecting the model formulation. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
235.
Löwen Kersten Meinhold Guido Güngör Talip Berndt Jasper 《International Journal of Earth Sciences》2017,106(8):2771-2796
International Journal of Earth Sciences - Detrital zircon U–Pb geochronology of 15 Late Palaeozoic to Early Mesozoic siliciclastic sandstones from the Karaburun Peninsula in western Turkey... 相似文献
236.
Elena Boari Riccardo Avanzinelli Leone Melluso Guido Giordano Massimo Mattei Arnaldo A. De Benedetti Vincenzo Morra Sandro Conticelli 《Bulletin of Volcanology》2009,71(9):977-1005
The “Colli Albani” composite volcano is made up of strongly silica-undersaturated leucite-bearing rocks. Magmas were erupted during three main periods, but a complex plumbing system dominated by regional tectonics channelled magmas into different reservoirs. The most alkali-rich magmas, restricted to the caldera-forming period (pre-caldera), are extremely enriched in incompatible trace elements and display more radiogenic Sr (87Sr/86Sr?=?0.71057–0.71067), with slightly less radiogenic Pb with respect to those of the post-caldera period. Post-caldera volcanic activity was concentrated in three different volcanic environments: external to the caldera, along the caldera edge and within the caldera. The post-caldera magmas produced melilite- to leucitite-bearing, plagioclase-free leucitites. In contrast to the pre-caldera lavas, they are characterised by lower incompatible trace element abundances and less radiogenic Sr (87Sr/86Sr?=?0.71006–0.71039). Magmas evolved through crystal fractionation plus minor crustal assimilation in a large magma chamber during the pre-caldera period. The multiple caldera collapses dissected and partially obliterated the early magma chamber. During the post-caldera stage, magmas were channelled through several pathways and multiple shallow-level magma reservoirs were established. A lithospheric mantle wedge previously depleted in the basaltic component and subsequently enriched by metasomatic slab-derived component is suggested as the mantle source of Colli Albani parental magmas. Two different parental magmas are recognised for the pre- and post-caldera stages. The differences may be related to the interplay between smaller degrees of melting for the pre-caldera magmas and more carbonate-rich recycled subducted lithologies in the post-caldera magmas. 相似文献
237.
238.
Biochemical responses in farmed mussel Perna perna transplanted to contaminated sites on Santa Catarina Island, SC, Brazil. 总被引:3,自引:0,他引:3
A C Bainy E A Almeida I C Müller E C Ventura I D Medeiros 《Marine environmental research》2000,50(1-5):411-416
The effects of contaminants on the biochemical parameters of the intensively farmed mussel Perna perna, are unknown. The aim of this study was to compare biochemical responses in mussels held in clean and contaminated sites in Santa Catarina Island, Brazil. Mussels were transplanted from a farming area, Ratones Grande Island (RGI), to two contaminated sites, Itacorubi (ITAC) and Hercílio Luz Bridge (HLB). A reference group was kept at RGI. After 150 and 180 days of exposure, the digestive glands of the mussels were analyzed for catalase, glucose 6-phosphate dehydrogenase (G6PDH) and glutathione S-transferase (GST) activities. No changes were observed in the catalase activity, in both periods. Low G6PDH activity was observed in mussels transplanted for 150 days at the ITAC site. Increased GST activity was observed in mussels from ITAC and HLG sites after 180 days. These responses are probably related to the augmented discharges of domestic effluents associated with elevated rainfall index. 相似文献
239.
Alexander J. Henshaw Prima W. Sekarsari Guido Zolezzi Angela M. Gurnell 《地球表面变化过程与地形》2020,45(2):331-344
Google Earth provides potential for exploiting an enormous reservoir of freely-available remotely sensed data to support river science and management. In this paper, we consider how the platform can support investigation of river physical forms and processes by developing an empirically-based reach-scale classification of semi-natural European single thread to transitional rivers. Using strict reach and image selection criteria, we identified 194 reaches of 68 rivers for analysis. Measurements of channel dimensions and counts of in-channel and floodplain features, standardised for reach length and channel width where necessary, were used to derive a series of geomorphologically-relevant process indicators. A suite of multivariate analyses were then applied to this data set, resulting in the discrimination of five river types: laterally stable, laterally active sinuous-meandering; transitional (near-braided); bedrock; and cascade/step dominated. The results of the classification were tested by examining the characteristics and distribution of the river classes in relation to known independent controls of river form including reach-scale energy and valley confinement conditions. Our results show that if methods of data extraction are carefully developed, physically meaningful river reach discrimination can be achieved using Google Earth. Although there are limits to the types of information that can be extracted such that field investigations cannot always be avoided, there is enormous potential to mine Google Earth across different space and time scales, supporting the assembly of large, reliable data sets relevant to river forms and processes in a very cost-effective way. © 2019 John Wiley & Sons, Ltd. 相似文献
240.
Guido Zolezzi Luca Carniello Andrea D'Alpaos Stefano Lanzoni Marco Tubino 《地球表面变化过程与地形》2020,45(5):1311-1314
This Special Issue collects 17 selected contributions from participants to the 10th edition of the RCEM (River, Coastal and Estuarine Morphodynamics) Symposium, organized in Padova-Trento (Italy) in September 2017. The series of biennial RCEM symposia has the key goal of enhancing interaction and promoting integration among the scientific communities focused on the morphological dynamics of river, coastal and estuarine environments, through various combinations of theoretical, observational, experimental and modelling approaches. The 17 contributions to this Special Issue contain four state-of-science reviews and overall offer a broad view of the cross-cutting perspective adopted when addressing morphodynamics. Such a perspective accounts for the mutual interplay between morphology, fluid dynamics and other environmental factors, and has presently become a widespread paradigm to address landscape evolution. © 2020 John Wiley & Sons, Ltd. 相似文献