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11.
Because of their physicochemical properties, biochars can be used as sorption materials for removal of toxic substances. The purpose of the present study was to determine whether biochar obtained from cones of larch (Larix decidua Mill. subsp. decidua) and spruce (Picea abies L. H. Karst) could be used as a sorbent for Cd2+, Pb2+ and Co2+ in aqueous solutions. So far, this feedstock had not been tested in this respect. The material was subjected to pyrolysis at 500 and 600 °C for the duration of 5, 10 and 15 min. The obtained pyrolysates were found to differ in terms of pH and the contents of the essential macroelements. The different values of these parameters were determined for varying temperature, duration of the pyrolysis process and type of feedstock. Sorption capacities of the biochars for removal of Cd2+, Pb2+ and Co2+ were examined using simulated contamination of aqueous solutions with salts of these metals. The findings showed the highest, nearly complete, removal for Pb2+ were maximum 99.7%, and almost three times lower value for Cd2+ and Co2+ (respectively, 35.7 and 24.8%). It was demonstrated that pyrolysis of conifer cones produced optimum sorption capacities when the process was conducted at a temperature of 500 °C for the duration of 5 min. It was shown that products of spruce cone pyrolysis were characterized by better sorption capacity in comparison with products of larch cone pyrolysis. The properties of conifer cone biochar create the possibility of using it as an adsorbent in water and wastewater treatment as well as in production of filters and activated carbon.  相似文献   
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The problem of two-dimensional mathematical modelling of heated cooling water discharges into running waters is considered in the paper. Two models — one for the evaluation of 2D turbulent velocity field and the other, developed by authors of the study, for 2D heat transport in open-channels — were used in the calculations. Relevant scenarios of the spread of heated water discharged from a designed gas-stem power plant to be constructed at the Vistula River were presented. Environmentally most friendly variant of the discharge of the thermal pollution was selected from among four various variants.  相似文献   
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This paper describes the two-phase study of the environmental impact of the SwePol Link submarine electrical energy transfer system between Sweden and Poland. During the first phase (1997–1998), the potential effects of proposed technical solutions for the transmission line and different routes across the Baltic Sea were analysed. During the second phase (1999–2000), studies on environmental and background conditions before cable installation (1999) and studies on the environmental effects after cable system installation (2000) were undertaken. During this phase, underwater TV and video inspection of the bottom, observations of the bottom habitats by scuba-divers, sampling and laboratory analysis of macrozoobenthos and measurements of the earth's magnetic field were conducted.Underwater observations along the cable route indicated that one year after the cable had been laid no mechanical disturbances on the dynamic sandy bottom were visible. Studies of the bottom macrofauna indicated that there had been no significant changes in zoobenthos species composition, abundance or biomass which could have been clearly related to cable installation. Changes in the components of the magnetic field, although significant in the vicinity of the cable itself, did not exceed natural variability at a distance of 20 m.  相似文献   
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Space technologies, such as kinematic Global Positioning System (GPS), often combined with an inertial navigation system (INS), provide an efficient direct georeferencing tool for remote sensing and aerial surveying. Practically, these systems are now able to deliver high-precision orientation data for spatial data acquisition platforms in a timely manner, at relatively low cost, as compared to traditional methods. The Airborne Integrated Mapping System (AIMS (TM)), developed at The Ohio State University Center for Mapping, integrates high-resolution digital imagery, differential GPS/INS, and precise timing for high-quality data acquisition supporting large-scale mapping and other precise positioning applications. In this article, the AIMS (TM) system hardware/software configuration, its current operational capabilities, and the test results of airborne mapping of the coastal zone are presented.  相似文献   
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Intensive suburbanization, especially in postsocialist countries, and a deficiency of fully public spaces result in an increasingly complex mixture of different types of spaces of public functions. Where there is a deficiency of completely public spaces, their role can be enhanced by those places available to the public for a specified period of time and under certain circumstances. Such places are provided and maintained not only by the public but also by the private sector. This article explores the diversity of places of public character and looks for criteria that organize this diversity. It introduces a new typology that corresponds mainly to the suburbs and combines five criteria of categorization: intended users, time limits as to access, prevailing form of control, intended functions, and visual characteristics. The typology draws attention to the role of spaces not intended for all the public but for selected groups and that of spaces with time-limited access. Such semipublic places are consistent with the lifestyle of suburbanites and therefore play an increasingly important role in suburban social life.  相似文献   
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The toxicity of sediments in the Gulf of Gdansk is analyzed in relation to the chemical composition of interstitial and near‐bottom waters, and sediment properties. The toxicity of sediments, pore waters and saline elutriates is determined by using the Microtox® test based on changes in light production of the luminescent bacteria Vibrio fischeri. The results indicate considerable toxicity in the majority of examined sediments. Since the sediment elutriates and pore waters are toxic in some cases, the total toxicity of the sediments is likely to be due to both sediment‐bound and water soluble substances. The sediment toxicity is related to the percentage contribution of the fine fraction of sediments. A significant correlation between the toxicity of the sediments and the black carbon content implies anthropogenic contamination. The toxicity of the sediments is seen to increase with the increase of hydrogen sulfide concentration in pore waters. The ammonia in pore waters was found not to be responsible for the toxicity of the sediments.  相似文献   
19.
This article aims to determine how three factors—the fence, the internal public space, and the type of building—affect the sense of community, as well as the perception of social divisions that gated communities generate and the need for integration between people living in and outside gated communities. Its results are based on the survey conducted in two villages, Józefos?aw and Julianów, located in the Warsaw metropolitan region. It has been found that the existence of a physical barrier in the form of a fence affects the perception of human relationships. Research has confirmed the negative impact of fencing off on social bonds, the sense of community, and attachment to the area beyond the housing estate. The study of Józefos?aw and Julianów, however, has proved that for the residents of suburban gated communities the key factor that can increase their sense of community is access to an internal public space. The sense of community and the attachment to the area of residence are also dependent on the type of building. Inhabitants of suburban gated communities dominated by multifamily housing are definitely characterized by a weaker attachment.  相似文献   
20.
A detailed geodetic survey and, additionally, a map of slope covers have been carried out for a composite relict rock glacier on the slopes of Mt ?l??a (718 m a.s.l.), Sudetic Foreland, SW Poland. The survey allows one to distinguish the mobilisation, transition and accumulation zones and to define geomorphic features diagnostic for relict rock glaciers such as lateral ridges standing above a central depression, steep margins of the landforms in the transition and accumulation zones, as well as absence of distinct head scarps above. Furthermore, it indicates that the present‐day hydrographic pattern on the surface of relict rock glaciers has been superimposed on the relief inherited from the active landforms. The topography indicates that tension prevailed rather than compression during the development of the rock glaciers. Some of the features, such as small lateral lobes, developed probably as a result of the compressive flow, however. The pattern of the slope cover shows that it developed during activity of the rock glaciers and been modified afterwards due to solifluction.  相似文献   
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