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1.
Glauco de Mottoni Y Palacios 《Icarus》1975,25(2):296-332
Using selected high quality plates collected at the I.A.U. Planetary Data Center in Meudon (Paris), the author has drawn 32 Mercator charts of the planet Mars for every opposition from 1907 to 1971. This graphic synthesis of albedo distribution may be used in the study of major surface changes over the years. 相似文献
2.
Coastal processes and environmental hazards: the Buenos Aires (Argentina) and Venetian (Italy) littorals 总被引：1，自引：0，他引：1
Jorge Pousa Luigi Tosi Eduardo Kruse Dardo Guaraglia Maurizio Bonardi Andrea Mazzoldi Federica Rizzetto Enrique Schnack 《Environmental Geology》2007,51(8):1307-1316
The Buenos Aires (Argentina) and Venice (Italy) coastlands have experienced significant saltwater contamination of the phreatic
aquifer, coastal erosion, hydrodynamic changes and relative sea level rise processes due to natural and man-induced factors.
These factors expose coastal areas to morpho-hydro-geological hazards, such as soil desertification, frequency and degree
of flooding, littoral erosion, and the silting of river mouths and channels. Man-made interventions and actions, such as beach
mining, construction of coastal structures and exploitation of aquifers without an adequate knowledge of the hydrology setting
and an adequate management program, worsen these natural hazards. Uncontrolled human activity induces environmental damage
to the overall coastal plains. The coastal plains play an important role in the social/economic development of the two regions
based on land use, such as agriculture, horticulture, breeding, and tourism, as well as industry. Results of investigations
on saltwater contamination, sea level rise and morphological changes recently performed in these two coastal areas are presented
here. 相似文献
3.
Glauco Gottardi 《Mineralogy and Petrology》1968,12(2-3):129-139
Summary The existence of chains of octahedra with tetrahedra as lateral appendixes in some Group-silicates is emphasized. These chains can be considered as building blocks; the different ways of juxta-posing the blocks offer a possibility of schematizing the structure of minerals (lawsonite, ilvaite, epidote, pumpellyite, perrierite, chevkinite), of explaining their twins and polymorphisms.
With 9 Figures 相似文献
Zusammenfassung Auf die Existenz von Oktaederketien mit Tetraedern als Seitenzusätzen in einigen Gruppensilikaten wird hingewiesen. Diese Ketten können als Bauteile betrachtet werden: beim Zusammensetzen dieser Bauteile kann man verschiedene Kristallstrukturen von Mineralien (Lawsonit, IIvait, Epidot, Pumpellyit. Perrierit, Tscheffkinit) darstellen, ihre Zwillingsbildung und einige Polymorphie-Typen erklären.
Riassunto Si prende in considerazione l'esistenza di catene di ottaedri con tetraedri come appendici laterali in alcuni sorosilicati. Queste catene possono essere considerate come elementi costruttivi: unendo tra di loro in vario modo questi elementi costruttivi si possono schematizzare le strutture di diversi minerali (lawsonite, ilvaite, epidoto, pumpellyite, perrierite, chevkinite), si possono spiegare le loro geminazioni, e certi tipi di polimorfismo.
With 9 Figures 相似文献
4.
This paper evaluates the concentration of Polyaromatic hydrocarbons - PAHs in the Estuarine area of the Patos Lagoon, more precisely in a local named "Saco do Laranjal" in Pelotas City (southern Brazil). The samples were collected in May 2008. The concentrations of 16 US-EPA priority polycyclic aromatic hydrocarbons (PAHs) were determined by gas chromatography with a mass spectrometry detector (GC/MS). The sum of PAHs concentration ranged from 7.3 to 92.8μgkg(-1) in dry weight. The positive correlation (Pearson test) between the total organic material (TOM) and the total PAH concentration (0.98) suggests that TOM plays an important role in controlling the PAHs levels in the sediments. According to the observed ratios of individual PAHs, the contamination in the studied area is originated, predominantly pyrolytic sources. The values found are considered under normal levels and indicates a not impacted area. 相似文献
5.
Silva Karita Almeida de Souza Rolim Glauco de Oliveira Aparecido Lucas Eduardo 《Theoretical and Applied Climatology》2022,148(3-4):1279-1288
Theoretical and Applied Climatology - The El Niño-Southern Oscillation (ENSO) phenomenon affects the global climate by changing temperature and precipitation patterns mainly in tropical... 相似文献
6.
AbstractThe impact of pollution incidents on rivers and streams may be predicted using mathematical models of solute transport. Practical applications require an analytical or numerical solution to a governing solute mass balance equation together with appropriate values of relevant transport coefficients under the flow conditions of interest. This paper considers two such models, namely those proposed by Fischer and by Singh and Beck, and compares their performances using tracer data from a small stream in Edinburgh, UK. In calibrating the models, information on the magnitudes and the flow rate dependencies of the velocity and the dispersion coefficients was generated. The dispersion coefficient in the stream ranged between 0.1 and 0.9 m2/s for a flow rate range of 13–437 L/s. During calibration it was found that the Singh and Beck model fitted the tracer data a little better than the Fischer model in the majority of cases. In a validation exercise, however, both models gave similarly good predictions of solute transport at three different flow rates. 相似文献
7.
Based on a non-linear dam-reservoir interaction model, a study investigating the earthquake response of concrete gravity dams is presented. For the propagation of cracks in unreinforced mass concrete, a discrete crack approach formulation based on the finite element method is applied. A special crack element is used to follow a fictitious crack in order to account for a zone of microcracks developing at the crack tip. The reservoir is modelled using the boundary element method. At a fictitious boundary dividing the irregular finite part of the reservoir from the regular infinite part, the loss of energy due to pressure waves moving away towards infinity is taken into account rigorously. Analyses are performed on the tallest non-overflow monolith of the Pine Flat Dam located in Kern County, California. The interaction of a dam, which may exhibit cracks in mass concrete, with a reservoir domain of arbitrary geometry extending to infinity is studied. Some main parameters are investigated. The importance of tools capable of handling the non-linear dam-reservoir interaction is emphasized. 相似文献
8.
Almeida Silva Karita de Souza Rolim Glauco Borges Valeriano Taynara Tuany da Silva Cabral de Moraes Jos&#; Reinaldo 《Theoretical and Applied Climatology》2020,139(3):1019-1029
Theoretical and Applied Climatology - Coffee is the most consumed beverage and one of the most valuable commodities worldwide. The crop is very sensitive to meteorological elements, mainly at the... 相似文献
9.
N.Yu. Agafonova M. Aglietta P. Antonioli G. Bari A. Bonardi V.V. Boyarkin G. Bruno W. Fulgione P. Galeotti M. Garbini P.L. Ghia P. Giusti F. Gomez E. Kemp V.V. Kuznetsov V.A. Kuznetsov A.S. Malguin H. Menghetti A. Pesci R. Persiani I.A. Pless A. Porta V.G. Ryasny O.G. Ryazhskaya O. Saavedra G. Sartorelli M. Selvi C. Vigorito L. Votano V.F. Yakushev G.T. Zatsepin A. Zichichi 《Astroparticle Physics》2008,28(6):516-522
In this paper we show the capabilities of the Large Volume Detector (INFN Gran Sasso National Laboratory) to identify a neutrino burst associated with a supernova explosion, in the absence of an “external trigger”, e.g., an optical observation. We describe how the detector trigger and event selection have been optimized for this purpose, and we detail the algorithm used for the on-line burst recognition. The on-line sensitivity of the detector is defined and discussed in terms of supernova distance and intensity at the source. 相似文献
10.
Patrick Hesp Janete Abreu de Castilhos Graziela Miot da Silva Sergio Dillenburg Caroline Thais Martinho Débora Aguiar Michele Fornari Milene Fornari Glauco Antunes 《地球表面变化过程与地形》2007,32(4):561-573
This paper examines a seemingly anomalous situation in southern Brazil where the dunefields on Santa Catarina Island (e.g. Joaquina Beach) migrate to the NNW, almost completely the opposite direction (c. 160) to the dunefields immediately to the south (e.g. Pinheira Beach), and some much further to the north (e.g. Cabo Frio) which migrate to the SSW. A variety of mechanisms are examined to explain the differences in dunefield migration including grain size variations, topographic effects on local winds, shoreline orientation, and regional wind field changes. The mean grain sizes of the two beaches, Pinheira and Joaquina, are not sufficiently different to restrict aeolian sediment transport in either place, nor to account for a lack of transport from the NNE to the SSW in the case of Joaquina. Some topographic steering of the wind is likely but could not account for the long‐term average difference in migration trends of the island dunefields compared to the mainland dunefields. While the orientation of the shoreline to prevailing winds is an important control on beach and dune sediment transport, it is not the dominant controlling mechanism. An analysis of the regional wind patterns demonstrates that there is a major shift in the regional wind field near the island such that the dominant island winds blow from the SW/SSW while those further south blow from the NE. It is concluded that this is the predominant reason for the divergence in the direction of migration of the dunefields. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献