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The paper presents the assessment of emission sources and health risk of 16 PAHs in the city of Novi Sad, Serbia, with developed oil, food, chemical and cement industry. Although the observed region has been previously studied with regard to the occurrence of PAHs in ambient air, the sources of emission and health risk using multivariate statistical methods have never been studied before. The research was conducted during the heating and non-heating periods at three sampling sites located in industrial, residential and high-traffic area. The samples were collected by high-volume air sampler and analysed using the GC/MS system. The data were processed using the positive matrix factorization (PMF) and cluster analysis. To assess the cancer-risk of PAHs, potency equivalency factor approach was used. The results of PMF analysis have indicated that significant sources of PAH emissions are industrial processes and diesel combustion during the non-heating, and coal combustion, heating plants and diesel combustion during the heating season. Cluster analysis of experimental data has confirmed the results obtained using the PMF method. Estimated values of lifetime lung cancer risk were higher than those set by the World Health Organization and US Environmental Protection Agency which indicates that cancer risk due to exposure to PAHs in ambient air exists in both time periods on the territory of Novi Sad.  相似文献   
13.
This article describes Professor David Mark’s considerable contributions over the last 11 years to research in Ethnophysiography, the study of terms used for landscape features in different languages, and toponyms (place-names). His preceding research is briefly discussed to provide a summary of the foundation from which ethnophysiography emerged. This article describes the key stages of development of this new field, including David Mark’s collaborations with Andrew Turk, David Stea, and others. It briefly summarizes the key theories used and the two ethnophysiography case studies undertaken thus far. This article provides an overview of how this collaborative transdisciplinary area of research has developed. It highlights the importance of David Mark’s scholarship in this process and indicates some of the impacts of the research.  相似文献   
14.
In Postojna Cave, air temperature and pressure monitoring has been conducted since July 21, 2008. Air pressure in the cave at three monitoring sites fluctuates synchronically with outside air pressure. Temperature data for Postojna 1 and 3 show good correlation with outside climate conditions for the period 2009?C2010. The temperature at Postojna 1 was increasing constantly from March to May 2009, while at Postojna 2, it was decreasing. Postojna 1 has a seasonal trend in accordance with outer trend, while seasonal trend at Postojna 2 is just contrary to outside trend. Microclimate studies at Postojna 2 show local variability, especially in winter, and exhibit special microclimate conditions that may be due to ventilation of unknown passages in the back.  相似文献   
15.
Cave air temperature, carbon dioxide concentrations in the cave air and external air temperature were analysed at several locations in Postojna Cave over the course of six holiday periods in 2009–2011. The results show that a 1-day increase in visitor numbers from 200 to 3,500 raised the cave air temperature by a maximum of 0.5 °C. The air temperature increases are within the annual range of cave air temperature variations. A fivefold increase in visitor numbers resulted in a carbon dioxide concentration that was at least twice as high as normal. The carbon dioxide concentration increased from 450 to 1,750 ppm (December 2009–January 2010). After 10 days of peak period visits, both the CO2 concentration and the temperature returned almost to the pre-holiday values. The gradual increase in mean annual air temperature in the cave (2004–2010) is not related to the number of visitors but to outside climate conditions.  相似文献   
16.
Although acidifying deposition in western North America is lower than in many parts of the world, many high‐elevation ecosystems there are extremely sensitive to acidification. Previous studies determined that the Mount Zirkel Wilderness Area (MZWA) has the most acidic snowpack and aquatic ecosystems that are among the most sensitive in the region. In this study, spatial and temporal variability of ponds and lakes in and near the MZWA were examined to determine their sensitivity to acidification and the effects of acidic deposition during and after snowmelt. Within the areas identified as sensitive to acidification based on bedrock types, there was substantial variability in acid‐neutralizing capacity (ANC), which was related to differences in hydrological flowpaths that control delivery of weathering products to surface waters. Geological and topographic maps were of limited use in predicting acid sensitivity because their spatial resolution was not fine enough to capture the variability of these attributes for lakes and ponds with small catchment areas. Many of the lakes are sensitive to acidification (summer and autumn ANC < 100 µeq L?1), but none of them appeared to be threatened immediately by episodic or chronic acidification. In contrast, 22 ponds had minimum ANC < 30 µeq L?1, indicating that they are extremely sensitive to acidic deposition and could be damaged by episodic acidification, although net acidity (ANC < 0) was not measured in any of the ponds during the study. The lowest measured pH value was 5·4, and pH generally remained less than 6·0 throughout early summer in the most sensitive ponds, indicating that biological effects of acidification are possible at levels of atmospheric deposition that occurred during the study. The aquatic chemistry of lakes was dominated by atmospheric deposition and biogeochemical processes in soils and shallow ground water, whereas the aquatic chemistry of ponds was also affected by organic acids and biogeochemical processes in the water column and at the sediment–water interface. These results indicate that conceptual and mechanistic acidification models that have been developed for lakes and streams may be inadequate for predicting acidification in less‐understood systems such as ponds. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
17.
Our paper presents a theoretical approach to critical research on web 2.0 cartographies. Within the geoweb, dynamic and collaborative web based maps have become a popular medium for collating and communicating geographic information. Web 2.0 cartographies are often promoted as facilitating public participation and democratizing geographic knowledge. Such claims demand a closer look at the processes through which people do engage in these cartographic projects and the multiple actors, institutions, norms and technologies at work. In the context of ‘theorizing the geoweb’, here we propose conceptual tools for analyzing these myriad interactions within web 2.0 cartographies. We understand web 2.0 cartographies as assemblages of subjects, materialities and practices, or ‘actor networks’. Yet explorations of actor‐networks describe existing relations and as a consequence tend to overlook what has been excluded or lies outside of such assemblages. In order to overcome this blindness we suggest bringing together actor‐network theory with the concepts of hegemonic discourses, contingency and the political from Chantal Mouffe and Ernesto Laclau. These two political theorists stress the idea that specific social realities become fixed, sedimented and perceived as natural while other possible social realities become marginalized. Using the example of the dynamic ‘Palestine Crisis Map’ (an Ushahidi Crowdmap) we demonstrate a methodology that emphasizes sensitivity towards moments of exclusion and struggle, where the political unfolds. Theorizing the political in this way extends the processual approach within Critical Cartography and offers a conceptual basis for critical research on the social dimensions of web 2.0 cartographies and geoweb practices.  相似文献   
18.
Like Participatory Geographic Information Systems (PGIS) and Public Participation Geographic Information Systems (PPGIS) crowdsourced collaborative mapping is often imagined as an alternative to conventional cartographic practice. This paper examines collaborative mapping projects designed to assist in humanitarian work and respond to catastrophes. These projects, their technological complexity and wide range of collaborators, including affected locals, international Non-Government Organisations (NGOs) and anonymous online contributors, invite closer consideration. In this article I unpick the gnarly question of how the remote sourcing of information through cloud collaboration and satellite imagery jostles with grounded work encouraging local control of local geoinformation. My critical analysis of these projects explores: (1) justifications for action – what is being promised through digital mapping as aid or satellite salvation?; (2) forms of participation – the role of ‘hotties’ ‘nodders’ and ‘digital jedis’; and (3) contingencies of mapping practices and the assemblages of actors within which they are embedded – as the mysteries of the ‘missing maps’. The conclusion considers differing approaches towards the inclusion of local knowledges within participatory digital aid mapping and identifies remote mapping practices that are both incognito and incognisant.  相似文献   
19.
The CO2 concentration of the air in Postojna Cave (400–7900 ppm) is found to be induced by CO2 sources (human respiration contributing?~?20,000–58,000 ppm per breath, outgassing of dripwater and water seeping from the vadose zone/epikarst with a pCO2 values of 5000–29,000 ppm, and underground Pivka River having pCO2 at 2344–4266 ppm) and CO2 dilution (inflow of outside air with a CO2 concentration of?~?400 ppm). Measurements show that sinking Pivka River has the lowest CO2 concentration among plausible CO2 sources but still continuously exceeds the surrounding cave air CO2 concentration. During the winter months, intensive ventilation reduces the cave air CO2 concentration to outside levels (~?400 ppm), even in the centre of the cave system. CO2 dilution is less pronounced in summer (CO2(min)?≈?800 ppm), since the ventilation rate is not as strong as in winter and the outside air that enters the cave through breathing holes and fractures is enriched with soil CO2. During spring and autumn, the daily alternation of the ventilation regime with a smaller rate of air exchange results in yearly cave air CO2 peaks of up to?~?2400 ppm. Some dead-end passages can be much less affected by ventilation, resulting in a cave air CO2 concentration of up to 7900 ppm. The strongest diurnal CO2 peaks due to human respiration were recorded during the spring holidays (increase of up to 1300 ppm day?1), compared to considerably smaller summer peaks despite peak visits (increase of?~?600 ppm day?1).  相似文献   
20.
A. Malej    P. Mozeti&#;    V. Mala&#;&#;  V. Turk 《Marine Ecology》1997,18(3):273-288
Abstract. Despite increasing evidence that atmospheric deposition may contribute considerably to new production in coastal seas, the role of this nutrient source in the shallow northern Adriatic ecosystem has remained largely unassessed. This study demonstrates that locally collected rain water significantly stimulates primary production and phytoplankton biomass accumulation in microcosm experiments. The concentration of nutrients in rain water collected during summer storms (11.38–77.19 μmol·1-1 nitrate. 4.45–36.38 μmol.1·1 ammonium, 0.93–4.75 μmol·1-1 phosphate) indicated that the precipitation is influenced by anthropogenic emissions from urbanised and industrialised regions of the European continent. Rainfall events delivered relatively large (127 tons nitrogen, 9.5 tons phosphorus in the period 10 June to 10 September, 1993). though episodic, nutrient input into the area. Field measurements showed that storm events were followed by an increase of phytoplankton standing crop and a shift of community structure.  相似文献   
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