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291.
Julie MacLeavy   《Geoforum》2008,39(5):1657-1666
Analysis of ‘neoliberalism’ in recent geographical work has usefully drawn attention to the manner in which certain political-economic ideas resonate with a diverse range of state projects, policy objects and socio-political imaginaries. Positioning neoliberalism as a multifaceted political phenomenon, scholars have explored its local manifestations: the embodiments of an express commitment to market exchange in specific geo-historical contexts. Key to this process, it is argued here, is the attempt to instil a series of values and social practices in policy subjects. This process can have lasting effects by virtue of being embedded in practices of governance at the local level, a dimension that has been given less attention in existing research. Using the implementation of the New Deals for the Unemployed and New Deal for Communities in Bristol as an illustrative case, this paper investigates this potentiality by positioning New Labour’s construction of social exclusion as a mechanism of neoliberalisation and exploring the legacy of the neoliberal values espoused in and through its social exclusion policies.  相似文献   
292.
Neoliberalism and the making of food politics in California   总被引:2,自引:0,他引:2  
Julie Guthman   《Geoforum》2008,39(3):1171-1183
This paper examines a philanthropy-led initiative which has as its objective to jump start the transition to a more sustainable and just food system in California. The first major project funded was a “vivid picture” of California’s food system twenty-five years in the future. The outcome of the project is a report that is glossed with the tropes of neoliberalism in all of its key organizing frameworks, analytics, cognitive maps, and idioms and argues for “opportunities-based approaches” as the engine of change. Yet, as described in the paper, this outcome was initially under-determined, and, in fact, the funders had originally intended to leverage their resources for large scale transformation. By examining four moments in the development of the Vivid Picture project, the grantee selection, the modeling exercise, the stakeholder meetings, and the qualitative interviews, this paper will show how existing techniques of neoliberal governance such as modeling, audit, best-practices, and stakeholder participation, as well as current norms of philanthropy, shaped what is thinkable and hence actable. It will also show how “stakeholders” played a constitutive role in producing the outcomes of the project, in part because their input reflected already-developed notions of the possible within the current climate of neoliberalism. In the end it will argue that the failure of the Vivid Picture to look beyond the neoliberal present is itself evidence of the proliferation of neoliberal governmentalities. Still, the entire process galvanized many of the movement actors who were left out of the funding process and, in that way, produced political openings.  相似文献   
293.
Two distinct hypoxic patterns were revealed from high-frequency dissolved oxygen (DO) data collected from North Branch of Onancock Creek, a shallow coastal estuary of the Chesapeake Bay, from July to October 2004. Diurnal hypoxia developed associated with large DO swings during fair weather and hypoxia/anoxia developed for prolonged 2–5-day periods following rainfall events. A simplified diagnostic DO-algae model was used to investigate DO dynamics in the creek. The model results show that the modeling approach enables important features of the DO dynamics in the creek to be captured and analyzed. Large anthropogenic inputs of nutrients to the creek stimulated macroalgae blooms in the embayment. High DO production resulted in supersaturated DO in daytime, whereas DO was depleted at night as the high respiration overwhelmed the DO supply, leading to hypoxia. Unlike deep-water environments, in this shallow-water system, biological processes dominate DO variations. High macroalgae biomass interacting with low light and high temperature trigger the development of prolonged hypoxic/anoxic postrainfall events.  相似文献   
294.
The Lagrangian Southern Ocean Iron Release Experiment (SOIREE) allowed study of a gradually evolving iron-mediated phytoplankton bloom in water labelled with the inert tracer sulfur hexafluoride, SF6. This article describes a pelagic carbon budget for the mixed layer in SOIREE and assesses the extent to which closure of the budget is achieved. Net community production (NCP) converted 837 mmol m−2 of inorganic carbon to organic carbon in 12.0 d after the first iron addition. A large fraction (41%) of NCP remained as particulate organic carbon in the mixed layer of the iron-enriched patch, while 23% was lost by horizontal dispersion and 0–29% was exported. The closure of the carbon budget is hampered by the lack of measurements of dissolved organic carbon (DOC), by a major uncertainty in carbon export, and by use of empirical conversion factors in estimates of carbon biomass and metabolic rates. Lagrangian carbon-budget studies may be improved by direct measurement of all major carbon parameters and conversion factors. Carbon cycling in the SOIREE bloom resembled that in ‘natural’ algal blooms in the open Southern Ocean in some respects, but not in all. Daily NCP in the SOIREE bloom (70 mmol m−2 d−1) was higher than in natural blooms, partly because other studies did not account for horizontal dispersion, were for longer periods or included less productive areas. The build-up of POC stock and carbon export as a fraction of NCP in SOIREE were in the lower range of observations elsewhere.  相似文献   
295.
Use of an airborne quartz crystal microbalance cascade impactor instrument together with a correlation spectrometer has allowed the flux of particles and their size distribution to be determined at Mount Erebus. The plume contributes 21±3 metric tomnes/day of aerosol particles to the Antarctic upper troposphere. The aerosol particles consist of larger (5–25 m) particles of elemental sulfur and silica, a middle sized group of iron oxides and smaller particles (less than 1 m) of complex liquids. Unlike many volcanic plumes, the Erebus plume has only a small amount of sulfate particles. The concentrations of particles in the Erebus plumes was 70–370 m/m3. Limited sampling of the Antarctic atmosphere at 8 km altitude but hundreds of km away from Erebus obtained a few large particles of sulfur and silicates, suggesting a similarity with the Erebus plume. The fallout of these particles occurs slowly over a broad area of the Antarctic continent.  相似文献   
296.
297.
The composition of basalts erupted at the earliest stages in the evolution of a back-arc basin permit unique insights into the composition and structure of the sub-arc mantle. We report major and trace element chemical data and O-, Sr-, Nd-, and Pb- isotopic analyses for basalts recovered from four dredge hauls and one ALVIN dive in the northern Mariana Trough near 22°N. The petrography and major element chemistry of these basalts (MTB-22) are similar to tholeiites from the widest part of the Trough, near 18°N (MTB-18), except that MTB-22 have slightly more K2O and slightly less TiO2. The trace element data exhibit a very strong arc signature in MTB-22, including elevated K, Rb, Sr, Ba, and LREE contents; relatively lowK/Ba and highBa/La andSr/Nd. The Sr- and Nd- isotopic data plot in a field displaced from that of MTB-18 towards Mariana arc lavas, and the Pb-isotopic composition of MTB-22 is indistinguishable from Mariana arc lavas and much more homogeneous than MTB-18. Mixing of 50–90% Mariana arc component with a MORB component is hypothesized. We cannot determine whether this resulted from physical mixing of arc mantle and MORB mantle, or whether the arc component is introduced by metasomatism of MORB-like mantle by fluids released from the subducted lithosphere. The strong arc signature in back-arc melts from the Mariana Trough at 22°N, where the back-arc basin is narrow, supports general models for back-arc basin evolution whereby early back-arc basin basalts have a strong arc component which diminishes in importance relative to MORB as the back-arc basin widens.  相似文献   
298.
Wastes from offshore oil drilling activities are often discharged to the marine environment. Solid wastes that settle onto the bottom sediment may pose a health threat to marine organisms and eventually to man through the food chain. We need to understand their fate in order to predict the chemical concentration levels and life-times in the sediment and adjoining aquatic boundary layer. A laboratory simulation of selected in-bed processes that addresses contaminant leaching from the sediment is proposed. The process chosen for simulation in this study is the coupled desorption-diffusion of contaminants from the bed to the water column. A simple mathematical model of the process is also proposed. Preliminary results using organic chemicals for both the simulation and the model are presented. The results suggest that the experimental procedure represents a good way of estimating the diffusive leaching rates of hydrophobic compounds from contaminated sediments.  相似文献   
299.
The chemical analyses of twenty-six minerals, four natural glasses, and one synthetic glass prepared for use as microprobe reference samples are presented. New chemical analyses of minerals and revised analyses of several minerals published previously are included. Details of sample preparation are described and the homogeneity of the samples has been tested by the homogeneity index.  相似文献   
300.
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