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51.
Isaac Luginaah Michael Jerrett Susan Elliott John Eyles Kate Parizeau Stephen Birch Tom Abernathy Gerry Veenstra Brian Hutchinson Chris Giovis 《GeoJournal》2001,53(2):135-147
This paper is part of a larger research program which employs a mixed-methods approach to study the determinants of health at the local level using specific neighborhoods in Hamilton, Ontario, Canada. In this paper, multivariate, spatial statistical techniques and geographic information systems are used to address questions about the characterization of neighbourhoods, based on socioeconomic determinants of health and risk factors such as smoking. While neighbourhood characterization has been a component of public health surveillance for some time, geostatistical techniques can now be used to derive more accurate representation of neighbourhoods for use in subsequent analysis. We utilize principal components analysis to reduce the data and extract the components that represent the underlying local processes. Principal components are also overlayed on comparative mortality figures to visualize where the socio-demographic determinants of health correspond spatially with mortality patterns. Predicted values from the components are then analysed for spatial clustering using local indicators of spatial association. The findings reveal a pattern of distinct neighbourhoods that will be used in subsequent quantitative and qualitative stages in the larger research programme. The results can also be used to inform public health policy and to target public health interventions. 相似文献
52.
Kate Boyer 《The Professional geographer》2004,56(2):201-212
At the end of the 19th century, the financial services sector underwent a technological “revolution” with the invention of the typewriter, dictaphone, and hollerith machine. At the same time, the gender of labor within this sector was also changing, such that by the end of the first quarter of the 20th century, most of the work taking place in white‐collar offices was performed by women. After introducing the broader research project on which this is based, I consider how technology and social relations shaped one another at the level of the body, the workplace, and with broader networks of branch banking, focusing on early 20th‐century Montreal, Canada. I argue that the financial services sector worked to create a system in which men flowed through and women functioned as fixed points. I further argue that this pattern was echoed at different scales within the financial services industry, from the level of the body and the workplace up through spatially dispersed national‐level networks. 相似文献
53.
Spatial variability of metals in the inter-tidal sediments of the Medway Estuary,Kent, UK 总被引:7,自引:0,他引:7
Spencer KL 《Marine pollution bulletin》2002,44(9):933-944
Concentrations of major and trace metals were determined in eight sediment cores collected from the inter-tidal zone of the Medway Estuary, Kent, UK. Metal associations and potential sources have been investigated using principal component analysis. These data provide the first detailed geochemical survey of recent sediments in the Medway Estuary. Metal concentrations in surface sediments lie in the mid to lower range for UK estuarine sediments indicating that the Medway receives low but appreciable contaminant inputs. Vertical metal distributions reveal variable redox zonation across the estuary and historically elevated anthropogenic inputs. Peak concentrations of Cu, Pb and Zn can be traced laterally across the estuary and their positions indicate periods of past erosion and/or non-deposition. However, low rates of sediment accumulation do not allow these sub surface maxima to be used as accurate geochemical marker horizons. The salt marshes and inter-tidal mud flats in the Medway Estuary are experiencing erosion, however the erosion of historically contaminated sediments is unlikely to re-release significant amounts of heavy metals to the estuarine system. 相似文献
54.
The Wild Bight Group (WBG) and South Lake Igneous Complex (SLIC) together comprise one of the Ordovician accreted oceanic
terranes of the central mobile belt of the Newfoundland Appalachians. Combined detailed mapping, geochemistry, Sm-Nd isotopic
studies and U-Pb geochronology have shown that sheeted dykes and hornblende diorite and tonalite plutons of the SLIC are genetically
related to a discrete package of volcanic rocks in the WBG. These igneous rocks are geochemically, isotopically and temporally
distinct from volcanic rocks in the rest of the WBG. Plutonic rocks of the SLIC range in age from 486 ± 3 Ma to 489 ± 3 Ma,
and a cross-cutting gabbro dyke gives a minimum age of 486 ± 4 Ma for the related volcanic sequence. Volcanic rocks in the
rest of the WBG sequence are predominantly younger than 472 ± 3 Ma. The older volcanic sequence of the WBG and the SLIC occur
as fault-bounded packages interleaved within the younger WBG sequence. A conformable stratigraphic relationship between the
older and younger sequences of the WBG has not been demonstrated. The mafic rocks of the older package include boninites and
low-Ti, high-Mg tholeiitic island arc basalts which are interpreted to be genetically related, and normal island arc tholeiites
(IAT). The high-Mg mafic rocks are interpreted to have formed in an extensional setting during subduction zone initiation,
and the normal IAT are thought to represent stabilisation of the volcanic front. The associated high-Si, low-K rhyolite and
tonalite are interpreted to be the products of secondary melting at the base of thickened early arc crust. Sm-Nd isotopic
compositions indicate that the characteristic trace element signature of the boninites developed at or near their time of
generation and was not a long lived characteristic of the source region. The boninites and low-Ti tholeiites are interpreted
to have originated from a similar source, which was metasomatized by different subduction-related components. Apparent decoupling
of Sm-Nd geochemical and isotopic compositions suggests that these very depleted rocks may be recording the effect of subduction
zone processes not yet fully understood.
Received: 31 October 1997 / Accepted: 6 May 1998 相似文献
55.
Land use on earth's landscape primarly indicates the degree of human interferance. Though landuse is controlled by several factors like soil, hydrologic, climatic, socio-economic and political yet geology and geomorphology play an important role in shaping landforms. The landforms processes mainly depend upon inherent lithology and structure of the earth. In the present paper an attempt has been made to study a sample area by air photo-interpretation technique using stereo-models and then evolve a methodology of land use mapping like photogeological and photopedological aspects. Also in brief, environmental aspects have been discussed. A sample area of 15 sq kms has been studied. The study opens up a new dimension for appreciation of resource and landuse management 相似文献
56.
Kate Manzo 《Geoforum》2003,34(4):437-456
This paper explores the rise of rights-based development (RBD) and its endorsement by prominent international institutions (such as the United Nations) and International Development Agencies (IDAs) like the World Bank. It situates RBD in global political context and analyses it in relation to the international politics of development, especially the politics of neo-liberal adjustment policies in Africa. The paper shows how RBD emerged against a backdrop of debate about four international issues associated with neo-liberalism and its discontents, namely globalisation and uneven development; capability and good governance; human rights and human development; and NGOs in the politics of development. Debates about those four issues keep repositioning the state as the central actor in RBD, and holding the state accountable for development (or the lack thereof) under international law. The paper’s basic point is that state-centric RBD is paradoxical and highly political. Greater accountability is being demanded of states––especially in Africa––from the same neo-liberal forces (such as the World Bank) charged with weakening state capacity, undermining democracy, and diminishing state authority. In terms of international power relations and the politics of development, RBD does signal something of a willingness to rethink certain aspects of the dominant neo-liberal agenda. And yet adjusted states are being subjected––in the name of RBD––to novel methods of international surveillance and forms of conditionality. States are ultimately held responsible for human rights violations, even when it is non-state actors (and their neo-liberal policies) that caused those rights to be violated in the first place. RBD is, therefore, a partial answer (at best) to the questions of empowerment and change raised by critics of neo-liberalism. 相似文献
57.
Camille A. Holmgren M. Cristina Pealba Kate Aasen Rylander Julio L. Betancourt 《Quaternary Research》2003,60(3):319-329
A new packrat midden chronology from Playas Valley, southwestern New Mexico, is the first installment of an ongoing effort to reconstruct paleovegetation and paleoclimate in the U.S.A.–Mexico Borderlands. Playas Valley and neighboring basins supported pluvial lakes during full and/or late glacial times. Plant macrofossil and pollen assemblages from nine middens in the Playas Valley allow comparisons of two time intervals: 16,000–10,000 and 4000–0 14C yr B.P. Vegetation along pluvial lake margins consisted of open pinyon–juniper communities dominated by Pinus edulis, Juniperus scopulorum, Juniperus cf. coahuilensis, and a rich understory of C4 annuals and grasses. This summer-flowering understory is also characteristic of modern desert grassland in the Borderlands and indicates at least moderate summer precipitation. P. edulis and J. scopulorum disappeared or were rare in the midden record by 10,670 14C yr B.P. The late Holocene is marked by the arrival of Chihuahuan desert scrub elements and few departures as the vegetation gradually became modern in character. Larrea tridentata appears as late as 2190 14C yr B.P. based on macrofossils, but may have been present as early as 4095 14C yr B.P. based on pollen. Fouquieria splendens, one of the dominant desert species present at the site today, makes its first appearance only in the last millennium. The midden pollen assemblages are difficult to interpret; they lack modern analogs in surface pollen assemblages from stock tanks at different elevations in the Borderlands. 相似文献
58.
Atomistic computer simulation methods have been used to model the nature of nonstoichiometry and impurity defects in the bulk and at the (101?4) surface of dolomite (MgCa(CO3)2). Calcium and Mg in the bulk and at the surface have been replaced with divalent Ni, Co, Zn, Fe, Mn, and Cd. The results of these calculations indicate that in the bulk, these impurities will prefer to substitute at the Ca site rather than the Mg site. Ca excess in dolomite is most likely incorporated as basal stacking faults; this nonstoichiometry can influence the site distribution of impurities. The calculated surface segregation energies suggest that of all the impurities studied, only Cd will show a strong preference for the (101?4) surface of dolomite. 相似文献
59.
Kate Coddington 《Geographical review》2019,109(4):527-543
In the U.K., refused asylum seekers who are considered destitute are provided with subsistence‐level financial support through the Azure card, a cashless technology similar to a debit card. In Australia, identical technology is used to quarantine fifty percent of the welfare benefits of mainly Aboriginal residents of the Northern Territory. In this paper, I explore the underlying state logics driving such punitive financial policies directed at these populations, arguing that cashless technologies represent a form of slow violence that employs financial tactics to undermine the provision of care for populations with precarious citizenship status. Financial tactics enact new forms of border securitization, slowly but permanently excluding people with precarious claims to citizenship from participation in the nation 相似文献
60.
Ludovic Puig Göran Pilbratt Astrid Heske Isabel Escudero Pierre-Elie Crouzet Bram de Vogeleer Kate Symonds Ralf Kohley Pierre Drossart Paul Eccleston Paul Hartogh Jeremy Leconte Giusi Micela Marc Ollivier Giovanna Tinetti Diego Turrini Bart Vandenbussche Paulina Wolkenberg 《Experimental Astronomy》2018,46(1):211-239
ARIEL, the Atmospheric Remote sensing Infrared Exoplanet Large survey, is one of the three M-class mission candidates competing for the M4 launch slot within the Cosmic Vision science programme of the European Space Agency (ESA). As such, ARIEL has been the subject of a Phase A study that involved European industry, research institutes and universities from ESA member states. This study is now completed and the M4 down-selection is expected to be concluded in November 2017. ARIEL is a concept for a dedicated mission to measure the chemical composition and structure of hundreds of exoplanet atmospheres using the technique of transit spectroscopy. ARIEL targets extend from gas giants (Jupiter or Neptune-like) to super-Earths in the very hot to warm zones of F to M-type host stars, opening up the way to large-scale, comparative planetology that would place our own Solar System in the context of other planetary systems in the Milky Way. A technical and programmatic review of the ARIEL mission was performed between February and May 2017, with the objective of assessing the readiness of the mission to progress to the Phase B1 study. No critical issues were identified and the mission was deemed technically feasible within the M4 programmatic boundary conditions. In this paper we give an overview of the final mission concept for ARIEL as of the end of the Phase A study, from scientific, technical and operational perspectives. 相似文献