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41.
《Urban geography》2013,34(5):514-542
In this article, we examine the sociospatial effects of market-driven social housing policies implemented in neoliberal Chile. The study area encompasses the Valparaíso—Viña del Mar conurbation and its surrounding peri-urban and peripheral municipalities. To analyze the urban dynamic between 1990 and 2005 we use data showing the allocation of social housing complexes built during three time periods, socioeconomic data disaggregated at the district level, and semistructured interviews conducted with strategic actors from the public and private sectors. We conclude that private developers are increasingly building social housing complexes in peripheral municipalities, fragmenting the sociospatial landscape and concentrating poor families in ghetto-like compounds. We also encountered local governments (municipalities) with little capacity to mobilize the resources that they hold, and communities that remain disconnected from their local representatives. 相似文献
42.
《Urban geography》2013,34(4):531-567
Scholars have often discounted social class as a substantial contributor to residential segregation by race, in part as a result of using the dissimilarity index, which is likely to show high levels of uneven group distribution regardless of socioeconomic status (SES), and in part as a result of using limited categories of SES. This study expands on prior research by examining residential segregation between black-alone and white-alone households in 36 metropolitan statistical areas (MSAs) with 2000 decennial census data, using both spatial unevenness (dissimilarity) and two types of experiential indicators (exposure indices), measuring SES across income levels and accounting for the presence of other races. Findings show that black households with higher incomes live in neighborhoods with greater exposure and lower isolation than do black households with lower incomes. Additionally, while the dissimilarity of black households decreases with income, unevenness is not as strongly connected to income as are the experiential measures. While race remains a primary determinant of residential segregation, results indicate substantial class differences. 相似文献
43.
《Urban geography》2013,34(4):589-605
This progress report is third in a series that examines the causes of segregation and the meaning and measurement of segregation. In this final report, we begin with the premise that ethnic and racial segregation carries tremendous impacts on the groups involved, altering their daily patterns and their future prospects. Yet the types of consequences that result from segregation depend on group dynamics; the social, political, and economic context; and a variety of contingent circumstances. In this essay, we review the recent literature on the outcomes of urban ethnic segregation and focus on some major themes that emerge from the literature. These themes include health and deprivation effects, how segregation can influence the group's employment prospects, how the fact of concentration may alter degrees of tolerance and intolerance, how segregation can augment levels of crime and violence, and finally the extent to which segregation influences the political and civic life of minority groups. 相似文献
44.
《Urban geography》2013,34(5):691-709
Municipalities create a local political geography that can institutionalize subordinate positions for minority groups. Most importantly, local governments determine which areas are incorporated into a municipality through annexation and which are excluded. Through these powers, local governments can diminish or deny minority political standing in local affairs, limit access to public services, and reduce the value of minority property. The boundaries are a component of racial residential segregation. Racially disparate application of local governments' power to shape local political geography creates barriers to equality that are difficult to discern on the ground, but which can be made visible by the mapping of spatial data. This study presents four cases where governmental decisions concerning a municipal boundary have institutionalized racial inequality, which is documented with maps created from public GIS data and other public records (e.g., City Council meeting minutes) as well as legal documents. This pattern of systematic exclusion of minority neighborhoods is receiving attention in the legal community, but studies in the social sciences have been limited. 相似文献
45.
基于城市化的中国能源消费前景分析及对碳排放的相关思考 总被引:3,自引:0,他引:3
工业化和城市化是中国未来的两大发展趋势.以往对中国未来能源消费及碳排放的预测大都是从工业化层面出发,忽略了城市化过程导致的生活能源消费的巨大增量.推动城市化进程是提升生活质量、满足人的基本权利的重要手段;立足城市化进程,保障人均能源消费及碳排放空间是确保人人享有基本的生存权和发展权的重要基础.从对中国城市化进程的发展态... 相似文献
46.
Frost heave is one of the main freezing problems for construction in permafrost regions.The Konrad-Morgenstern segregation potential(SP) model is being used in practice for frost heave using numerical techniques.However,the heat release from in-situ and migrated water in the freezing zone could result in some numerical instability,so the simulation of frost fringe is not ideal.In this study,a semi-analytical solution is developed for frost heave prediction of clay soil.The prediction results to the two tests with different freezing mode with clay soil agree well with the tested behavior,which indicates the feasibility of the solution. 相似文献
47.
The inner shelves of active, energetic continental margins are frequently defined as regions of sediment segregation and fine-sediment bypassing. The Waiapu River, North Island, New Zealand presents an opportunity to study fine-sediment segregation and strata formation in a spatially constrained, highly energetic, aggradational setting, with one of the highest sediment yields on earth. We present evidence that the inner shelf of the Waiapu River plays a significant role in both the fate of fine-grained (<63 μm) riverine sediments and the formation of continental margin stratigraphy. Results obtained from high-resolution interferometric bathymetry and high-frequency seismic mapping ground-truthed by cores show significant stratigraphic spatial variation preserved on the Waiapu inner shelf. This spatial variation is likely controlled by spatially-distinct sediment deposition and resuspension processes as well as antecedent geology. Two distinct depositional regions are interpreted as: (1) surface plume-dominated with partial resuspension, characterized by acoustically transparent seismic reflection profiles and muddy sands; and (2) event-layer dominated, characterized by thickly laminated sediments. A modern-day bathymetric low overlying an observed paleochannel may influence the fate of hyperpycnal flows transiting the shelf via bathymetric steering. Fining-upward sequences found over the entire shelf are interpreted to represent deforestation-induced sedimentation that has overwhelmed the ability of the energetic system to resuspend and segregate fine sediments. We conclude that the primary control on strata formation on the inner shelf of the Waiapu River is local sediment supply. 相似文献
48.
49.
Microstructural tectonometamorphic processes and the development of gneissic layering: a mechanism for metamorphic segregation 总被引:6,自引:1,他引:5
The Mary granite, in the East Athabasca mylonite triangle, northern Saskatchewan, provides an example and a model for the development of non-migmatitic gneissic texture. Gneissic compositional layering developed through the simultaneous evolution of three microdomains corresponding to original plagioclase, orthopyroxene and matrix in the igneous rocks. Plagioclase phenocrysts were progressively deformed and recrystallized, first into core and mantle structures, and ultimately into plagioclase-rich layers or ribbons. Garnet preferentially developed in the outer portions of recrystallized mantles, and, with further deformation, produced garnet-rich sub-layers within the plagioclase-rich gneissic domains. Orthopyroxene was replaced by clinopyroxene and garnet (and hornblende if sufficient water was present), which were, in turn, drawn into layers with new garnet growth along the boundaries. The igneous matrix evolved through a number of transient fabric stages involving S-C fabrics, S-C-C' fabrics, and ultramylonitic domains. In addition, quartz veins were emplaced and subsequently deformed into quartz-rich gneissic layers. Moderate to highly strained samples display extreme mineralogical (compositional) segregation, yet most domains can be directly related to the original igneous precursors. The Mary granite was emplaced at approximately 900 °C and 1.0 GPa and was metamorphosed at approximately 750 °C and 1.0 GPa. The igneous rocks crystallized in the medium-pressure granulite field (Opx–Pl) but were metamorphosed on cooling into the high-pressure (Grt–Cpx–Pl) granulite field. The compositional segregation resulted from a dynamic, mutually reinforcing interaction between deformation, metamorphic and igneous processes in the deep crust. The production of gneissic texture by processes such as these may be the inevitable result of isobaric cooling of igneous rocks within a tectonically active deep crust. 相似文献
50.
甘肃西秦岭新生代钾霞橄黄长岩中的球状分凝体及地幔流体反演 总被引:1,自引:0,他引:1
地幔流体在地质过程中的作用日益受到人们的重视,成为地球科学研究的一个前缘课题。提供了甘肃西秦岭新生代钾霞橄黄长岩中各种形态分凝体详细的岩相学、矿物学和矿物化学的资料,对分凝体的性质、深部地幔流体的成分及成因机制进行了讨论。研究表明,钾霞橄黄长岩中分凝体是软流圈地幔流体活动的记录,其成因机制与岩浆作用对软流圈的开放和软流圈上涌的条件下,原生钾霞橄黄长岩浆的分异作用(特别是液态不混熔作用),以及岩浆的抽提作用、动态熔融作用等综合作用有关。 相似文献