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61.
Joyce Davidson 《Area》2000,32(1):31-40
Summary Drawing on individual and group interviews with agoraphobic women, this paper explores sufferers' accounts of agoraphobia as entailing apparent dysfunctions in spatial awareness. In particular, it examines the effects of agoraphobic anxiety on the lived boundaries of body and self and relates this to agoraphobics' contrasting experiences of the relative 'security' of the home and the unheimlich and disturbing architecture of the shopping mall.  相似文献   
62.
63.
Geological hazards and their effects are often geographically widespread. Consequently, their effective mapping and monitoring is best conducted using satellite and airborne imaging platforms to obtain broad scale, synoptic coverage. With a multitude of hazards and effects, potential data types, and processing techniques, it can be challenging to determine the best approach for mapping and monitoring. It is therefore critical to understand the spatial and temporal effects of any particular hazard on the environment before selecting the most appropriate data type/s and processing techniques to apply. This review is designed to assist the decision-making and selection process when embarking on a hazard mapping or monitoring exercise. It focuses on the application of optical, LiDAR, and synthetic aperture RADAR technologies for the assessment of pre-event risk and post-event damage. Geological hazards of global interest summarized here are landslides and erosion; seismic and tectonic hazards; ground subsidence; and flooding and tsunami.  相似文献   
64.
The large-scale geological structure of the crystalline rock at the proposed high-level nuclear waste repository site at Forsmark, Sweden, has been classified in terms of deformation zones of elevated fracture frequency. The rock between deformation zones was divided into fracture domains according to fracture frequency. A methodology to constrain the geometric and hydraulic parameters that define a discrete fracture network (DFN) model for each fracture domain is presented. The methodology is based on flow logging and down-hole imaging in cored boreholes in combination with DFN realizations, fracture connectivity analysis and pumping test simulations. The simulations suggest that a good match could be obtained for a power law size distribution where the value of the location parameter equals the borehole radius but with different values for the shape parameter, depending on fracture domain and fracture set. Fractures around 10–100 m in size are the ones that typically form the connected network, giving inflows in the simulations. The report also addresses the issue of up-scaling of DFN properties to equivalent continuous porous medium (ECPM) bulk flow properties. Comparisons with double-packer injection tests provide confidence that the derived DFN formulation of detailed flows within individual fractures is also suited to simulating mean bulk flow properties and their spatial variability.  相似文献   
65.
The sonochemical degradation of 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) in water and wastewater was investigated at ultrasonic frequency of 850 kHz. The effects of pH, initial concentrations, temperature, power and dissolved organic carbon were examined. The results obtained indicated that the rate of ultrasonic degradation of E2 and EE2 in water and wastewater is influenced by the pH, power, air sparging and the dissolved organic content of the aqueous solutions. Mass degradation rates of E2 and EE2 per kW ranged from 1.7 to 4.0 mg kW?1 at varying process parameters. The degradation process followed the pseudo-second-order kinetic model with rate constant of 1.71 × 10?2 min?1 at 25 °C. The value for activation energy (E a = 15.21 kJ mol?1) obtained from Arrhenius-type plot, indicated that the ultrasonic degradation of steroid hormones is thermodynamically feasible, and does not progress only on radical reactions but other intermediate reaction processes. In wastewater, the higher dissolved organic carbon significantly reduced the effectiveness of degradation of the E2 and EE2 showing that ultrasound treatment will be more effective as a tertiary treatment option in wastewater applications.  相似文献   
66.
This paper presents the enrichment tendency and spatial distribution of metals in the groundwater which is pumped out from the granitic aquifers in South Africa. Groundwater is the sole source of water supply for the local community in the study area (Namaqualand), and hence, it was necessary to understand the controlling geochemical processes and interrelationship of metals in the groundwater. The geochemical association of metals has been assessed based on the geostatistical methods. The results show that geochemical processes such as oxidation, leaching, and evaporation besides water–rock interaction are very important in controlling metal enrichment in the groundwater from highly mineralized rocks. The metal enrichment index for selected toxic metals in groundwater increases in the order of Cd > U > Cr > Pb. The observed enrichment trend could be considered as a result of mineralization of basement rocks which is facilitated by active geochemical process in the arid environment. The lack of aquifer flushing due to negligible recharge helps the metals to concentrate at shallow groundwater zones supported by severe evaporation process.  相似文献   
67.
The Namaqualand area is located in the Northern Cape Province of South Africa which is characterised by arid climate where groundwater is the only source of water supply for local communities. Extensive groundwater sampling was carried out in the area and the physico-chemical parameters, inorganic constituents, stable isotopes and trace metals were measured. The hydrochemistry of the area indicates dissimilar groundwater composition due to complex geochemical processes where groundwater flow takes place from catchment F30A to the catchment D82B, and the chemistry is controlled primarily by Redox reaction, dissolution and mixing processes. The Br?/Cl? ratio revealed that the salinity in the area is derived from seawater mixing, halite dissolution and atmospheric deposition/sea aerosol spray. Under excessive evaporative condition due to climatic aridity, groundwater salinity shows increasing trend. Isotope results show the presence of shallow-weathered zone and deep-fracture controlled circulating groundwater in the crystalline basement aquifer of the area. In comparison to the South African water quality standard, the results obtained for gross alpha activity which could be derived from uranium isotopes show that 41 % of the reported data in the area fall above the drinking water limit.  相似文献   
68.
The Recreation Opportunity Spectrum (ROS) has been used internationally as a tool to guide recreation planning. The spectrum as a map has primarily been generated manually and through digitisation by analysts with an in-depth knowledge of the region of interest. This paper seeks to outline an alternative method that is objective and repeatable to create a ROS map for New Zealand, using data from a variety of sources and manipulated with spatial tools available in a geographic information system. The result is a map that is consistent on a national scale, and a method that is repeatable. The model can be used to develop scenario modelling, change detection, and help guide management decisions.  相似文献   
69.
Mid-Holocene age fossil-fringing reefs occur along the tectonically stable north coast of Java, Indonesia, presenting an opportunity for sea level and paleoclimate reconstruction. The fossil reef at Point Teluk Awur, near Jepara, Central Java, contains two directly superposed horizons of Porites lobata microatolls. Corals in the lower horizon, 80 cm above modern sea level, yielded Uranium series dates of 7090 ± 90 year BP, while corals in the upper horizon at 1.5 m grew at 6960 ± 60 year BP. These dates match the transgressive phase of regional sea-level curves, but suggest a mid-Holocene highstand somewhat older than that recorded on mid-Pacific islands. Paleotemperature was calibrated using Sr/Ca and δ18O values of a modern P. lobata coral and the locally measured sea surface temperature (SST), yielding SST–Sr/Ca and SST–δ18O calibration equations [T Sr/Ca = 91.03–7.35(Sr/Ca) and Td18 \textO T_{{\delta^{18} {\text{O}}}}  = −3.77 to −5.52(δ18O)]. The application of the local equations to Sr/Ca and δ18O measurements on these corals yielded a range of temperatures of 28.8 ± 1.7°C, comparable to that of the modern Java Sea (28.4 ± 0.7°C). A paleo-salinometer [Δδ18O = ∂δ18O/∂T ( Td18 \textO T_{{\delta^{18} {\text{O}}}}  − T Sr/Ca)], re-calculated using the local parameters, also suggests Java Sea mid-Holocene paleosalinity similar to modern values.  相似文献   
70.
Nonlinear analysis of rainfall dynamics in California's Sacramento Valley   总被引:1,自引:0,他引:1  
This study investigates the dynamic nature of rainfall observed at the Sustainable Agriculture Farming Systems (SAFS) site in California's Sacramento Valley, which was established to study the benefits of winter cover cropping in Mediterranean irrigated‐arid systems. Rainfall data of four different temporal scales (i.e. daily, weekly, biweekly, and monthly) are analysed to determine the dynamic nature of precipitation in time. In an arid climate with seasonal precipitation this has large implications for land and water management, both in the short term and in the long term. A nonlinear dynamic technique (correlation dimension method) that uses the phase‐space reconstruction and dimension concepts is employed. Bearing in mind the possible effects of the presence of zeros (i.e. no rain) on the outcomes of this analysis, an attempt is also made to compare the dynamic nature of all‐year rainfall and winter rainfall. Analysis of 15 years of data suggests that rainfall dynamics at this site are dominated by a large number of variables, regardless of the scales and seasons studied. The dimension results also suggest that: (1) rainfall dynamics at coarser resolutions are more irregular than that at finer resolutions; (2) winter rainfall has a higher variability than all‐year rainfall. These results are indeed useful to gain information about the complexity of the rainfall process at this site with respect to (temporal) scales and seasons and, hence, the appropriate model (high‐dimensional) type. However, in view of the potential effects of certain rainfall data characteristics (e.g. zeros, measurement errors, scale effects) on the correlation dimension analysis, the discussion also emphasizes the need for further verification, and possibly confirmation, of these results. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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