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51.
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53.
The Dahuiyeh (Zarand) earthquake of 2005 February 22 in central Iran: reactivation of an intramountain reverse fault 总被引:3,自引:0,他引:3
54.
The problem of the diversity of the geochemical types of carbon dioxide waters (CDW) in petrografically and mineralogically uniform crystalline rock masses is solved with allowance made for the effect of different boundary conditions (physicochemical parameters) on the geochemical effect of interaction in the rock–water system. The formation of the entire geochemical spectrum of CDW in crystalline rock masses is shown to be explicable on the basis of a model of interaction in granite–water systems at different mass ratios of reacting rock (S) and water (L), different temperatures T, and equilibrium concentrations of dissolved CO2 (P
CO2). 相似文献
55.
Virtual vegetables and adopted sheep: ethical relation, authenticity and Internet-mediated food production technologies 总被引:2,自引:1,他引:2
Lewis Holloway 《Area》2002,34(1):70-81
Associating ideas related to cultural geographies of 'quality' food production and consumption with recent discussion of Internet technologies, virtuality and simulation, this paper examines two newly constituted Internet enterprises offering customers 'virtual' experiences of food production, and 'quality' food products in which they have invested. The paper shows how these enterprises are associated with particular types of geographical and ethical relation, and a search for 'authentic', connected, relationships with food, farming, locality and 'nature'. These relationships are constituted in an assemblage of things held together by flows of food, products, money and electronic communication. The paper ends by suggesting a number of theoretical ideas that might usefully be explored in empirical research into Internet-mediated food production. 相似文献
56.
The paper presents the first quantitative results of a laboratory study of the velocity field in a two-arm spiral-wave pattern generated in a steady-state fashion by a hydrodynamical instability in a differentially rotating, thin layer of liquid. The liquid layer has a free surface, and the rotational profile includes an interval where the velocity drops abruptly, as in the gaseous disks of spiral galaxies. The properties of anticyclonic vortices observed between the arms of this pattern at the corotation radius are considered. 相似文献
57.
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Contamination of groundwater has become a major concern in recent years. Since testing of water quality of all domestic and irrigation wells within large watersheds is not economically feasible, one frequently used monitoring strategy is to develop contamination potential maps of groundwater, and then prioritize those wells located in the potentially highly contaminated areas for testing of contaminants. However, generation of contamination potential maps based on groundwater sensitivity and vulnerability is not an easy task due inherent uncertainty. Therefore, the overall goal of this research is to improve the methodology for the generation of contamination potential maps by using detailed landuse/pesticide and soil structure information in conjunction with selected parameters from the DRASTIC model. The specific objectives of this study are (i) to incorporate GIS, GPS, remote sensing and the fuzzy rule-based model to generate groundwater sensitivity maps, and (ii) compare the results of our new methodologies with the modified DRASTIC Index (DI) and field water quality data. In this study, three different models were developed (viz. DIfuzz, VIfuzz and VIfuzz_ped) and were compared to the DI. Once the preliminary fuzzy logic-based (DIfuzz) was generated using selected parameters from DI, the methodology was further refined through VIfuzz and VIfuzz_ped models that incorporated landuse/pesticide application and soil structure information, respectively. This study was conducted in Woodruff County of the Mississippi Delta region of Arkansas. Water quality data for 55 wells were used to evaluate the contamination potential maps. The sensitivity map generated by VIfuzz_ped with soil structure showed significantly better coincidence results when compared with the field data. 相似文献
59.
Sensitivity kernels for finite-frequency surface waves 总被引:1,自引:1,他引:1
60.