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E. Azoulay M. Colin J. Dubreuil H. Dou G. Mille G. Giusti 《Marine environmental research》1983,9(1):19-36
In marine sediments from the Mediterranean coast polluted by oil spills (Etang de Berre) high bacterial activity is responsible for self-purification, samples collected from these areas showing a bacterial density several orders of magnitude higher than samples from non-polluted areas (Isle des Embiez). Between 60 and 80 % of the heterotrophic bacteria in the polluted areas are hydrocarbon-degrading, compared with 0.01 % in the non-polluted area.Several strains of hydrocarbon utilisers were isolated, a mixture of strains from each biotope was taken to represent a ‘biotope population’ and their activity towards different types of hydrocarbons (n-alkanes, iso-alkanes, cycloalkanes, aromatics) was determined.With ammonia as the nitrogen source the ‘biotope population’ from the polluted area degraded hydrocarbons much more readily than the ‘biotope population’ from the non-polluted area. With nitrate as the nitrogen source the degradation was much reduced, and, for some hydrocarbons, ceased in both ‘populations’.Individual hydrocarbons encouraged the growth of individual strains in the ‘biotope population’. In natural mixtures of hydrocarbons all strains grew well and degraded aliphatics. There was a good correlation between the respiratory activity of the ‘biotope population’ and the ability of the ‘population’ to utilise hydrocarbons for growth. 相似文献
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An approach for quantifying geomorphological impacts for EIA of transportation infrastructures: a case study in northern Spain 总被引：2，自引：0，他引：2
Jaime Bonachea Viola Maria Bruschi Juan Remondo Alberto Gonzlez-Díez Luis Salas Jurjen Bertens Antonio Cendrero Csar Otero Cecilia Giusti Andrea Fabbri Jos Ramn Gonzlez-Lastra Jos María Aramburu 《Geomorphology》2005,66(1-4):95
A methodological proposal for the assessment of impacts due to linear infrastructures such as motorways, railways, etc. is presented. The approach proposed includes a series of specific issues to be addressed for each geomorphological feature analysed—both ‘static’ and ‘dynamic’—as well as a series of steps to be followed in the process.Geomorphic characteristics potentially affected were initially identified on the basis of a conceptual activities/impacts model that helps to single out geomorphic impacts related to environmental concerns for the area. The following issues were addressed for each individual impact: nature of potential effects; indicators that can be used to measure impacts; criteria of ‘geomorphologic performance’; procedure for measurement/prediction of changes; translation of geomorphologic impacts into significant terms from the viewpoint of human concerns; possible mitigation and/or compensation measures.The procedure has been applied to a case study corresponding to a new motorway in the Basque Country, northern Spain. Geomorphological impacts considered in this analysis included: (1) consumable resources; (2) sites of geomorphological interest; (3) land units with high potential for use, high productivity or value for conservation; (4) visual landscape; (5) slope instability processes. The procedure has been designed for implementation in a Geographic Information System (GIS) environment. Details are given on the application of the method to each individual impact analysed and results are presented in both numerical and map form.Impacts assessed were initially expressed by means of heterogeneous magnitudes, depending on the geomorphological feature considered. Those geomorphological impacts were then translated into significant terms and homogeneous magnitudes. Integration was carried out on the basis of impact values thus obtained. Final integrated results were also expressed in numerical and map form.The method proposed enables comparison of alternatives as well as ‘prediction’ and assessment of impacts in terms directly related to geomorphic characteristics. It also facilitates the expression of those impacts in terms that allow integration with other types of environmental impacts. 相似文献
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Giusti E. Martorella M. Petronio C. Berizzi F. 《Geoscience and Remote Sensing Letters, IEEE》2008,5(2):152-156
Scattering type classification represents a significant step toward target classification. Both the surface of Poincare's sphere and Cameron's unit disc have been used separately to represent symmetric scattering matrices and to define classification methods. In this letter, the equivalence of using the surface of Poincare's sphere and Cameron's unit disc in terms of characterization and classification of symmetric scattering types is demonstrated mathematically. 相似文献
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Summary The detailed characteristics of 435 placer gold grains from the North Saskatchewan and Athabasca rivers have been investigated using a combination of optical microscopy, energy dispersive electron microprobe analysis and SEM techniques. Most grains show high-fineness rims surrounding lower-fineness cores (giving an extreme range of 4.3%–46.1% Ag within an individual grain). Characteristics of the rims lend support to the hypothesis that they are the products ofin situ leaching of silver followed by transport which largely destroys a spongy texture produced by the leaching. There is no change in the average Ag content of grains of any given size range with distance downstream, which also indicates that all significant leaching takes place before transportation. However, differences are apparent in the average Ag content with grain size.The clustering about certain values of fineness of the nuclei of grains which is seen in samples from both rivers, suggests that Au was largely derived from specific sources in the mountains (Omineca geanticline) to the west rather than redistributed from Shield localities during glaciation.
With 9 Figures 相似文献
Mikrosonden-Untersuchungen an Seifengold aus Alberta, Kanada
Zusammenfassung 435 Körner aus Goldseifen im North Saskatchewan und im Athabasca-Fluß wurden einer detaillierten Untersuchung mit optischer Mikroskopie, energie-dispersiver Mikrosondenanalytik und Rasterelektronenmikroskopie unterzogen.In den meisten Körnern umgibt ein Rand mit hohem Feinheitsgrad einen Kern mit niedrigem Feinheitsgrad (dies führt zu beträchtlichen Schwankungen des Ag-Gehaltes innerhalb des einzelnen Kornes; im Extremfall 4,3%–46,1% Ag). Die Charakteristik der Ränder gibt Anlaß zu der Hypothese, daß das Silber dieser Ränder in situ herausgelöst worden ist, bevor die Körmer transportiert wurden; die während des Transportes auf die Körner einwirkenden Kräfte haben dann die poröse Textur, die durch das herauslösen des Silbers entstanden waren, weitgehend zerstört. Es findet sich keine Änderung des durchschnittlichen Ag-Gehaltes mit zunehmender Transportweite flußabwärts, solange nur Kömer aus einem Größenintervall betrachtet werden. Dies deutet ebenfalls darauf hin, daß der überwiegende Teil des Silbers vor dem Transport herausgelöst wurde. Man findet jedoch Unterschiede im durchschnittlichen Ag-Gehalt zwischen Körnern verschiedener Größe.Das Auftreten von mehreren bestimmten Werten-Clustern der Feinheitsgrade, die in Proben aus beiden Flüssen zu finden ist, legt nahe, daß Au zum größten Teil aus mehreren, spezifischen Ursprungsgesteinen in den westlich gelegenen Gebirgen (Omineca Geanticline) stammt. Eine glazigene Umverteilung von Gold aus verschiedenen Lokalitäten des Kanadischen Schildes erscheint weniger realistisch.
With 9 Figures 相似文献
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Advancements in hydrology proceeded slowly until the late 1800's when new ventures created a surge of interest and accomplishment. Progress waned again until the middle 20th century when an International Hydrological Decade was conceived, eventually receiving wide multinational support from governmental agencies and nongovernmental institutions.Organized by UNESCO, the Decade program was launched January 1, 1965. Participation included 107 nations, six United Nations agencies, and more than a dozen international scientific organizations. The initial program emphasized scientific research, and international cooperation; the second half of the Decade, emphasized technical assistance and technology transfer, largerly through education, training and demonstration.The success of the Decade led to the establishment of the International Hydrological Program, again under the aegis of UNESCO, to continue the work of the Decade indefinitely. The five major program activities, now involving about 90 countries and several international organizations, include: the scientific program, the promotion of education and training, the enhancement of information exchange, support of technical assistance, and the enlargement of regional cooperation.A significant amount of activity related to hydrological data networks and forecasting is carried on in an Operational Hydrology Programme by the WMO, chiefly through its Commission for Hydrology.Other international governmental organizations with a strong interest in water include the UN, the UN Development Programme, the FAO, the WHO, the International Atomic Energy Agency, the UN Environment Programme, the International Standardization Organization, and developmental institutions such as the World Bank.The specialized interests of researchers outside of the governmental structure, are met through association in various scientific and technical organizations which are world wide in scope and membership.Notwithstanding a sometimes bewildering variety of organizations, there certainly exists, for any nation, group, or individual, a demonstrated mechanism for almost any conceivable form of international cooperation in hydrology and water resources.Dr. Heindl, L.A., formerly US Geological Survey, died on October 18, 1978 (see In Memoriam at the end of the paper) before he could finish the final version. His colleagues, James R. Jones, Robert M. Beall and Ennio V. Giusti, Office of International Hydrology, US Geological Survey, Reston, VA. 22092, USA, kindly prepared the paper for publication and wrote In Memoriam. Approved for publication by the Director, US Geological Survey. 相似文献
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Domenico Giusti George E. Konidaris Vangelis Tourloukis Mattia Marini Matteo Maron Andrea Zerboni Nicholas Thompson George D. Koufos Dimitris S. Kostopoulos Katerina Harvati 《Boreas: An International Journal of Quaternary Research》2019,48(3):713-730
By applying advanced spatial statistical methods, spatial taphonomy complements the traditional taphonomic approach and enhances our understanding of biostratinomic and diagenetic processes. In this study, we elaborate on a specific aspect – spatial anisotropy – of taphonomic processes. We aim to unravel the taphonomic history of the Early Pleistocene vertebrate assemblage of Tsiotra Vryssi (Mygdonia Basin, Greece). Circular statistics are used for the fabric analysis of elongated elements; geostatistics (directional variograms), wavelet and point pattern analyses are applied for detecting anisotropy at the assemblage level. The anisotropy of magnetic susceptibility (AMS) of sedimentary magnetic minerals is also investigated. The results, integrated with preliminary remarks about the differential preservation of skeletal elements, sedimentological and micromorphological observations, suggest multiple dispersion events and recurrent spatial re‐arrangement of a lag, (peri)autochthonous assemblage, consistent with the cyclical lateral switching of a braided fluvial system. Furthermore, this study offers a contribution to the building of a spatial taphonomic referential framework for the interpretation of other fossil vertebrate assemblages, including archaeo‐palaeontological ones. 相似文献
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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
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A high-temperature geothermal resource has been located on the island of St Lucia (W.I.), which was tapped by means of a well drilled in 1988 to a total depth of 1410 m, in the Sulphur Springs area. The well encountered mainly dacitic agglomerates and lava flows and a permeable zone below ≈1340 m, with a maximum temperature of ≈290°C.Well productivity decreased from an initial value close to 62 t/h to about 33 t/h under well-head pressures of 1.5 MPa (15 bar a) after 255 h of production. Initial reservoir static pressure was 7.5 MPa (75 bar a). A decline in reservoir pressure of about 15% was observed at the end of the production test. During the first two days of exploitation the well initially produced a two-phase fluid with high steam fraction, which then developed into superheated steam with a high content of non-condensable gas exceeding 100 1/kg at standard conditions and a computed P(CO2) of 1 MPa (10 bar).The average steam fraction at reservoir conditions, computed from gas composition after 120 h of production is 0.3.High HCl concentrations of about 300 ppm are present in the condensate steam indicating the presence of a high concentrated boiling brine to the point of halite saturation. All data support the hypthesis of a hydrothermal hot-water system prior to drilling, that underwent a very rapid drawdown with production. 相似文献
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Gilbert Mille Yan Yu Chen Gérard Giusti Henri Dou Evelyne Vacelet Marie-Reine Plante-Cuny 《Marine environmental research》1984,11(3):213-232
The evolution of hydrocarbons in sediments was studied from 1978 to 1980 at eight stations in the Ile Grande marshes (Brittany) polluted by the Amoco Cadiz oil spill. Generally, in 1980 (except for one heavily polluted site) the amounts of hydrocarbons were found to be far less important than in 1978 and sometimes biogenic hydrocarbons were found. In the superficial layer of the sediments biodegradation processes were generally important with the preferential degradation of n-alkanes. On the other hand, aromatic hydrocarbons seem not to have been altered after three years. Degradation of percolated hydrocarbons proceeds more slowly than in the surface layer. The number of degrading bacteria decreases when n-alkanes disappear. 相似文献
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