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11.
Bronwyn Parry   《Geoforum》2008,39(3):1133-1144
Richard Titmuss’ classical 1970 study of blood donation has provided a powerful conceptual model for characterising transactions involving human bodily materials. This now paradigmatic model suggests that such transactions are typically organised in accordance with one or other of two dichotomous, and mutually exclusive, modes of exchange: gifting or commodification. In this paper I utilise findings from my own and others’ empirical research to illustrate the range of complex, multiply constituted, and contested modes of commodification that now typically attend the exchange of human body parts and tissues of which Titmuss’ model can take no effective account. Drawing on work by Radin, Callon, and Miller I illustrate the complex justificatory work that those involved must perform to fit their lived experiences of tissue exchange into this now outmoded paradigm. I then consider how the protagonists themselves ontologise their practices and with what effects. In the second part of the paper I consider how neo-liberal ideologies and instruments are being employed to suborn a variety of highly differentiated and geographically distinct practices of bodily commodification to the ‘logic of the market’. I explore here what the operative effects of defining the global circulation of body parts and tissues as a new ‘economy’ might be. I then consider how, if at all, a market logic could ‘Value’ all those ‘calculations of interest’ and ‘values’ that underpin exchanges of human body parts and tissues in specific national, communal or institutional settings. I conclude by reflecting on the desirability or possibility of performing normative assessments of the ethicacy of highly geographically and culturally differentiated practices of bodily commodification.  相似文献   
12.
Undisturbed specimens of a soft clayey silt have been taken vertically, horizontally and at 45° to the vertical at the base of a trench and submitted to consolidation and undrained triaxial compression and extension tests in the laboratory. Undrained shear strengths and compressibilities are found to be strongly dependent on sample orientation, but the effective stress strength parameters are shown to be much more influenced by stress path than sample orientation. The pore-pressure response vs axial strain is shown to be unaffected by sample orientation. Most of the anisotropic effects are shown to be eliminated by successively consolidating the specimens under isotropic pressure increments and re-testing in undrained shear. Some of the evidence from the experimental programme indicates that tension resisting bonds act between the grains of the soil specimens.  相似文献   
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Subsurface video footage can be used as a successful identification tool for various marine organisms; however, processing of such information has proven challenging. This study tests the use of automated software to assist with photo-identification of the great white shark Carcharodon carcharias in the region of Gansbaai, on the south coast of South Africa. A subsurface photo catalogue was created from underwater video footage. Single individuals were identified by using pigmentation patterns. From this catalogue, two images of the head for each individual were inserted into automated contour-recognition software (Interactive Individual Identification System Beta Contour 3.0). One image was used to search the database, the other served as a reference image. Identification was made by means of a contour, assigned using the software to the irregular border of grey and white on the shark's head. In total, 90 different contours were processed. The output provided ranks, where the first match would be a direct identification of the individual. The method proved to be accurate, in particular for high-quality images where 88.24% and 94.12%, respectively, were identified by two independent analysts as first match, and with all individuals identified within the top 10 matches. The inclusion of metadata improved accuracy and precision, allowing identification of even low-quality images.  相似文献   
15.
This paper describes the trials undertaken within a domestic landfill site to assess the feasibility of constructing a cement solidified retaining structure using deep soil mixing. The trials consisted of individual columns extending to the full depth of the landfill, each using different concrete mixes and mixing auger configurations to assess the most successful combinations to achieve full depth, followed by the construction of two trial blocks incorporating several different concrete mixes. The trial blocks were constructed to evaluate the most effective concrete and auger combinations required to construct the retaining structure which if built would be approximately 150 m in length, 15 m deep and 10 m wide.

Grout cube strength has been measured during column installation and post construction the columns were exhumed and core samples taken for laboratory analysis of compressive strength, permeability, freeze/thaw and long-term immersion tests.

The trials have met with only moderate success and indicate that a combination of depth and a difficult substrate as is likely to be encountered in older landfills will severely hinder the process of column installation. No amount of previous characterisation can determine the conditions likely to be encountered at a particular location in such a heterogeneous material.

It is suggested that the calculation of likely success rate for column installation and construction of a large retaining structure can be based on the failure rate of cable percussion boreholes during site investigation. If the failure is greater than 15% the technique is unlikely to be viable.  相似文献   

16.
Some of the magnetic properties of dispersions of immobilized multidomain magnetite particles are determined by intrinsic crystalline properties but others are strongly affected by the state of division and the particle shape. Various theories of magnetization have included shape effects but the experimental evidence is meagre, due principally to the great difficulty in determining precisely the amount of magnetite. A series of measurements have been made on dispersions of particles which appear to be pure magnetite with only a non-magnetic gangue-mineral impurity. The specimens used contained low concentrations of magnetite — so the specimen shape was unimportant — and either restricted particle sizes or bimodal size-distributions. The results are not in agreement with either the previously proposed value of the shape factor nor with the properties of mixed particle-sizes.  相似文献   
17.
Nonpoint source pollution control is a more complicated process than traditional analysis suggests. Whether a new pollution abatement technology is developed exogenously or endogenously and the per unit reduction in the rate at which a pollutant associated with the use of a factor of production needed to produce an agricultural commodity due to this technology enters the environment are critical factors in the determination of the effects of agricultural production on the pollutant stock. These are the issues addressed here. The optimal current period research and development expenditures on an endogenously induced abatement technology associated with the use of a factor of production giving rise to environmental externalities are shown to be a function of, among other things, the cumulation of all research and development expenditures, the probability of an abatement technology being developed, the level of use of the factor of production, the unit pollution tax on the factor, the rate of time preference (discount rate), the rate at which the pollutant associated with the factor enters the environment, the rate of discharge of the pollutant stock, and so forth. Finally, the analysis demonstrates that a reduction in pollution by the adoption of an abatement technology may lead to an increase in the pollutant stock as a result of endogenous technological change associated with the pollution abatement. When the rate of pollution reduction is greater than a threshold, however, the adoption of an endogenously determined abatement technology will unequivocally lead to a reduction in the pollutant stock.The views expressed are those of the authors and do not necessarily represent the policies of the US Department of Agriculture or the views of other US Department of Agriculture staff members.  相似文献   
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The Blackfoot Reservoir region in southeastern Idaho is recognized as a potential geothermal area because of the presence of several young rhyolite domes (50,000 years old), Quaternary basalt flows, and warm springs. North- to northwest-trending high-angle normal faults of Tertiary to Holocene age appear to be the dominant structural control of spring activity. Surface spring-water temperatures average 14°C except for a group of springs west of the Reservoir Mountains which average 33°C. Chemical geothermometers applied to fifty water samples give temperatures less than 75°C except for eight springs along the Corral Creek drainage. The springs along Corral Creek have Na-K-Ca temperatures that average 354°C, a direct result of high potassium concentrations in the water. A correction for carbon dioxide applied to the Na-K-Ca geothermometer lowers the estimated temperatures of the anomalous springs to near the measured surface temperatures, and Na-K-Ca-Mg temperatures for the anomalous springs are near 100°C. Mixing model calculations suggest that hot water with a temperature of approximately 120°C may be mixing with cooler, more dilute water in the springs from the Corral Creek drainage, a temperature supported by Na-K-Ca-Mg temperatures and mineral saturation temperatures.Stability relations of low-temperature phases in the system indicate that the large concentrations of potassium in the eight anomalous springs are derived from reactions with the potassium-bearing minerals muscovite and K-feldspar. Carbon dioxide and hydrogen sulfide gases may be derived through the oxidation of organic matter accompanied by the reduction of sulfate. Concentrations of major and minor elements, and gases found in springs of the Blackfoot Reservoir region are due to water-rock reactions at temperatures less than 100°C.Based on spring geochemistry, a geothermal reservoir of 100°C up to 120°C may exist at shallow (less than 2 km) depths in the Blackfoot Reservoir region.  相似文献   
20.
The Consequences of CO2 Stabilisation for the Impacts of Climate Change   总被引:1,自引:0,他引:1  
This paper reports the main results of an assessment of the global-scale implications of the stabilisation of atmospheric CO2 concentrations at 750 ppm (by 2250) and 550 ppm (by 2150), in relationto a scenario of unmitigated emissions. The climate change scenarios were derived from simulation experiments conducted with the HadCM2 global climate model and forced with the IPCC IS92a, S750 and S550 emissions scenarios. The simulated changes in climate were applied to an observed global baseline climatology, and applied with impacts models to estimate impacts on natural vegetation, water resources, coastal flood risk and wetland loss, crop yield and food security, and malaria. The studies used a single set of population and socio-economic scenarios about the future that are similar to those adopted in the IS92a emissions scenario.An emissions pathway which stabilises CO2 concentrations at 750 ppmby the 2230s delays the 2050 temperature increase under unmitigated emissions by around 50 years. The loss of tropical forest and grassland which occurs by the 2050s under unmitigated emissions is delayed to the 22nd century, and the switch from carbon sink to carbon source is delayed from the 2050s to the 2170s. Coastal wetland loss is slowed. Stabilisation at 750 ppm generally has relatively little effect on the impacts of climate change on water resource stress, and populations at risk of hunger or falciparum malaria until the 2080s.A pathway which stabilises CO2 concentrations at 550 ppm by the 2170s delays the 2050 temperature increase under unmitigated emissions by around 100 years. There is no substantial loss of tropical forest or grassland, even by the 2230s, although the terrestrial carbon store ceases to act as a net carbon sink by around 2170 (this time because the vegetation has reached a new equilibrium with the atmosphere). Coastal wetland loss is slowed considerably, and the increase in coastal flood risk is considerably lower than under unmitigated emissions. CO2 stabilisation at 550 ppm reduces substantially water resource stress, relative to unmitigated emissions, but has relatively little impact on populations at risk of falciparum malaria, and may even cause more people to be at risk of hunger. While this study shows that mitigation avoids many impacts, particularly in the longer-term (beyond the 2080s), stabilisation at 550 ppm appears to be necessary to avoid or significantly reduce most of the projected impacts in the unmitigated case.  相似文献   
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