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91.
Increasing penetration by the market into the governing of agri-environments, and the use of market-oriented approaches in an attempt to produce more sustainable outcomes, is a characteristic feature of what scholars have called the ‘neoliberalisation of nature’. While accepting that neoliberal forms of governing tend to extend market relations into new domains, a number of scholars have argued that they may at the same time create spaces of resistance, open up progressive political possibilities, or incorporate alternative rationalities of governing. This literature has so far focused primarily on the policy and/or programme level with limited connection made to the growing body of research that explores landholder responses to specific market instruments. We address this gap by focusing on a market instrument – Wimmera Habitat Tender – in the State of Victoria, Australia, which aims to provide incentives for farmers in managing native vegetation. This case study explores how a specific tender-based market instrument seeks to construct natural resource managers as neoliberal subjects, as well as the complex ways in which farmers contest or resist the neoliberal governing of their agri-environmental practices. Through our analysis we contend that closer scrutiny of how the techniques underpinning market-based environmental instruments are taken up or resisted contributes to a more robust understanding of the environmental possibilities created by market instruments, as well as the challenges involved in attempts to neoliberalise nature. 相似文献
92.
Abstract Environmental data are often utilized to guide interpretation of spectral information based on context, however, these are also important in deriving vegetation maps themselves, especially where ecological information can be mapped spatially. A vegetation classification procedure is presented which combines a classification of spectral data from Landsat‐5 Thematic Mapper (TM) and environmental data based on topography and fire history. These data were combined utilizing fuzzy logic where assignment of each pixel to a single vegetation category was derived comparing the partial membership of each vegetation category within spectral and environmental classes. Partial membership was assigned from canopy cover for forest types measured from field sampling. Initial classification of spectral and ecological data produced map accuracies of less than 50% due to overlap between spectrally similar vegetation and limited spatial precision for predicting local vegetation types solely from the ecological information. Combination of environmental data through fuzzy logic increased overall mapping accuracy (70%) in coniferous forest communities of northwestern Montana, USA. 相似文献
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S. Vaughan Th. Boller A. C. Fabian D. R. Ballantyne W. N. Brandt J. Trümper 《Monthly notices of the Royal Astronomical Society》2002,337(1):247-255
We present an XMM–Newton observation of the bright, narrow-line, ultrasoft type 1 Seyfert galaxy Ton S180. The 0.3–10 keV X-ray spectrum is steep and curved, showing a steep slope above 2.5 keV (Γ∼ 2.3) and a smooth, featureless excess of emission at lower energies. The spectrum can be adequately parametrized using a simple double power-law model. The source is strongly variable over the course of the observation but shows only weak spectral variability, with the fractional variability amplitude remaining approximately constant over more than a decade in energy. The curved continuum shape and weak spectral variability are discussed in terms of various physical models for the soft X-ray excess emission, including reflection off the surface of an ionized accretion disc, inverse Compton scattering of soft disc photons by thermal electrons, and Comptonization by electrons with a hybrid thermal/non-thermal distribution. We emphasize the possibility that the strong soft excess may be produced by dissipation of accretion energy in the hot, upper atmosphere of the putative accretion disc. 相似文献
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Dr.AlanP.M.Vaughan 《《幕》》2004,27(3):218-219
Although the terrane concept emerged from the study of northern hemisphere active continental margins and orogenic belts, it is largely in the Southern Hemisphere, in particular in relation to the Gondwana supercontinent, where it has seen its fullest flowering. New data continue to emerge, and new models and techniques are being actively developed. For these reasons, “Terrane Processes at the Pacific-margin of Gondwana” 相似文献
99.
ABSTRACT A conceptual model is proposed in which bulk transtension, or local transtension during bulk simple shear (resulting from mantle anisotropy contrasts or lithosphere rheology contrasts), of heterogeneously enriched lithospheric mantle, triggers localized K-rich magmatism, which focuses strain and causes nucleation of lithosphere-scale transtensional or strike-slip shear zones. Transtension-triggered magmatism is most likely to be located at sites of maximum metasomatism of the lithospheric mantle. Magma-generated fractures propagate upwards, nucleating zones of lithospheric weakness, which focus shear in narrow transcurrent faults or at basin margins. In this way, magmatism controls fault timing and location. Although volcanism will be coeval with fault development and volcanoes will appear fault-controlled, counterintuitively, our model suggests that faults are, in a sense, volcano-controlled. We suggest that this new transtension – K-rich magmatism – transcurrent faulting association represents a hitherto unrecognized genetic relationship as significant as, for example, the ocean island magma series. 相似文献
100.
L. J. Carpenter Z. L. Fleming K. A. Read J. D. Lee S. J. Moller J. R. Hopkins R. M. Purvis A. C. Lewis K. Müller B. Heinold H. Herrmann K. Wadinga Fomba D. van Pinxteren C. Müller I. Tegen A. Wiedensohler T. Müller N. Niedermeier E. P. Achterberg M. D. Patey E. A. Kozlova M. Heimann D. E. Heard J. M. C. Plane A. Mahajan H. Oetjen T. Ingham D. Stone L. K. Whalley M. J. Evans M. J. Pilling R. J. Leigh P. S. Monks A. Karunaharan S. Vaughan S. R. Arnold J. Tschritter D. Pöhler U. Frieß R. Holla L. M. Mendes H. Lopez B. Faria A. J. Manning D. W. R. Wallace 《Journal of Atmospheric Chemistry》2010,67(2-3):87-140
Observations of the tropical atmosphere are fundamental to the understanding of global changes in air quality, atmospheric oxidation capacity and climate, yet the tropics are under-populated with long-term measurements. The first three years (October 2006–September 2009) of meteorological, trace gas and particulate data from the global WMO/Global Atmospheric Watch (GAW) Cape Verde Atmospheric Observatory Humberto Duarte Fonseca (CVAO; 16° 51′ N, 24° 52′ W) are presented, along with a characterisation of the origin and pathways of air masses arriving at the station using the NAME dispersion model and simulations of dust deposition using the COSMO-MUSCAT dust model. The observations show a strong influence from Saharan dust in winter with a maximum in super-micron aerosol and particulate iron and aluminium. The dust model results match the magnitude and daily variations of dust events, but in the region of the CVAO underestimate the measured aerosol optical thickness (AOT) because of contributions from other aerosol. The NAME model also captured the dust events, giving confidence in its ability to correctly identify air mass origins and pathways in this region. Dissolution experiments on collected dust samples showed a strong correlation between soluble Fe and Al and measured solubilities were lower at high atmospheric dust concentrations. Fine mode aerosol at the CVAO contains a significant fraction of non-sea salt components including dicarboxylic acids, methanesulfonic acid and aliphatic amines, all believed to be of oceanic origin. A marine influence is also apparent in the year-round presence of iodine and bromine monoxide (IO and BrO), with IO suggested to be confined mainly to the surface few hundred metres but BrO well mixed in the boundary layer. Enhanced CO2 and CH4 and depleted oxygen concentrations are markers for air-sea exchange over the nearby northwest African coastal upwelling area. Long-range transport results in generally higher levels of O3 and anthropogenic non-methane hydrocarbons (NMHC) in air originating from North America. Ozone/CO ratios were highest (up to 0.42) in relatively fresh European air masses. In air heavily influenced by Saharan dust the O3/CO ratio was as low as 0.13, possibly indicating O3 uptake to dust. Nitrogen oxides (NOx and NOy) show generally higher concentrations in winter when air mass origins are predominantly from Africa. High photochemical activity at the site is shown by maximum spring/summer concentrations of OH and HO2 of 9?×?106 molecule cm?3 and 6?×?108 molecule cm?3, respectively. After the primary photolysis source, the most important controls on the HOx budget in this region are IO and BrO chemistry, the abundance of HCHO, and uptake of HOx to aerosol. 相似文献