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51.
Simone Scarpa 《Urban geography》2016,37(7):963-984
In recent years, residential segregation has become a major issue in the Swedish policy debate. The prevailing view is that residential segregation is a crucial contributing factor to the development of income inequality, since individual income prospects are thought to be influenced by the population characteristics of their neighbourhoods. This study takes the opposite approach and analyses the extent to which, in the period 1991–2010, rising income inequality contributed to the development of residential segregation by income in Swedish metropolitan areas. The period was characterized by unprecedented growth in income inequality, which was associated with a decline in the redistributive power of the welfare state. Residential segregation by income mirrored locally the general trend in income inequality. Another factor was the change in income dispersion in neighbourhoods, relative to the metropolitan areas as a whole, which indicates a tendency towards increased population homogeneity in neighbourhoods with respect to income. 相似文献
52.
Javier Ruiz-Tagle 《Urban geography》2016,37(3):352-372
Public policies of social mixing have been enacted as the reversal of what segregation and concentrated poverty are presumed to have produced: intensified social problems (i.e., “neighborhood effects”). In addition, the pervasive discourses of diversity have provided more support for the idea of social mixing. Studies on planned and unplanned diverse neighborhoods have shown how certain diverse patterns can emerge and endure over time. Yet these studies have failed to explain how such demographic diversity becomes integration. In this article, I draw on a multidimensional perspective of socio-spatial integration to present a qualitative case study of the Cabrini Green/Near North area in Chicago—a neighborhood with a long history of segregation and recent socially engineered diversity. The case shows how contentious this new coexistence has been, and how segregation has been shifting its mechanisms of enforcement from housing to other spheres of life. I conclude with reflections on four dimensions of socio-spatial integration, and on the troubling policy and theoretical implications of the “social mix” paradigm. 相似文献
53.
The Urban Heat Island (UHI) is a well-documented phenomenon occurring in cities across the world resulting in city centres often being several degrees warmer than their surroundings. This local elevation in temperatures could potentially impact upon local energy consumption, with residents in the warmer central section of the city using more energy to cool their homes in summer and less energy to warm them in winter. This study uses a combination of Geographical Information System techniques and Remote Sensing data (MODIS LST and NDVI), as a preliminary investigation, to assess the spatial relationship between UHI, urban greenspace, household income and electricity consumption in Birmingham, UK. It provides simple and repeatable steps, based on freely available datasets, for urban planners, industry, human and physical geographers, and non-specialists to reproduce the analyses. The results show that, the present impact of the UHI is limited and instead highlights the dominance of household income over local climate in explaining consumption patterns across Birmingham. 相似文献
54.
Mixed-ethnicity partnerships are becoming increasingly common in Australia and other countries of high immigration. Formal and de facto marriages involving partners from different ethnic backgrounds are key indicators of decreasing social distance between groups. Yet mixed-ethnicity couples have received scant attention from Australian geographers. We use customised data from the 2011 Australian census to analyse the nation-wide distribution of several types of mixed-ethnicity couples. We focus on couples comprised of an Anglo-European (ethnic majority) partner, and a partner from a ‘visible’ ethnic minority group. Our analyses explore the residential geographies of mixed-ethnicity couples vis-à-vis ‘co-ethnic couples’ (where partners share the same ethnicity). We find that mixed-ethnicity couples are more widely dispersed across Australian cities and regions than comparative co-ethnic couples. However, each type of mixed-ethnicity couple has its own unique residential pattern: there are multiple geographies of mixed-ethnicity couples in Australia. These distinctive patterns reflect the migration and settlement histories of the couples’ constituent ethnic groups, but also hold great potential to shift seemingly entrenched ethnic residential geographies in the present and future. 相似文献
55.
56.
四川攀西地区几个小型镁铁-超镁铁岩体含矿性的铂族元素示踪 总被引:2,自引:0,他引:2
峨眉山大火成岩省内带,四川攀西地区的杨合伍、黄草坪和清水河等镁铁-超镁铁岩体分布在南北向的安宁河断裂和磨盘山-元谋断裂之间。分析表明,这些岩体无矿岩石与金宝山、杨柳坪、力马河等含矿岩体无矿岩石具有相似的铂族元素组成,普遍较高的Cu/Pd比值暗示这些岩体的母岩浆在侵入到目前层位前经历过硫化物熔离作用。定量模拟计算表明,原始岩浆经过大约0.01%的硫化物熔离作用形成了杨合伍岩体母岩浆,经过0.035%硫化物熔离形成了黄草坪和清水河岩体的母岩浆。根据硫化物熔离情况,认为杨合伍等岩体底部可能形成Ni-Cu-(PGE)硫化物矿床,而黄草坪和清水河岩体之下及附近可能存在Ni-Cu硫化物矿化的岩体。 相似文献
57.
A.J. Christopher 《Geoforum》2004,35(2):145-156
South Africa is a multi-lingual country with 11 official languages and a recent history where language was frequently used as a political instrument, notably in the urban areas. Although the cities were initially colonial foundations, as a consequence of rural-urban migration, the speakers of the various national languages have come into close contact with one another. However, as a result of the inheritance of apartheid town planning and its emphasis on racial zoning, residential segregation levels between some linguistic groups have been extremely high. An analysis of the 1996 census results reveals that the uniformly high segregation levels between the speakers of indigenous African languages and the speakers of Afrikaans and English are the direct outcome of apartheid era town planning. Nevertheless, segregation between the speakers of different African languages may also on occasion be relatively high where homeland political policies were pursued, although this was the exception rather than the rule. Similarly segregation between English and Afrikaans speakers was locally high where home language coincided with former racial classification. Few immediate significant changes are anticipated in the present patterns of linguistic segregation, as the inherited apartheid city structure is proving to be remarkably resistant to transformation. 相似文献
58.
Abstract Middle Miocene to Quaternary primitive basalts and high magnesian andesite (HMA) in North Hokkaido resulted from three periods of intense volcanism; early-stage (12–10 Ma), middle-stage (9–7 Ma) and late-stage (3–0 Ma). Based on the chemical compositions of olivines and chromian spinels and bulk chemistry of the primitive rocks, we examined depths of segregation of the calculated primary magmas and the degrees of partial melting of the source mantle. In the context of asthenospheric mantle upwelling, petrological data from the present study can be accounted for by the secular change in the depth of magma segregation from the upwelled asthenospheric mantle, which is composed of fertile peridotite. Thus, the early-stage primary magmas were generated by higher degrees of partial melting of the shallower part of hot asthenospheric mantle, whereas the middle- and late-stage primary magmas resulted from lower degrees of partial melting of a deeper part of the asthenospheric mantle. The early-stage HMA magma was generated by partial melting of the remnant subcontinental lithospheric mantle composed of refractory peridotite. This melting might have resulted from an increased geothermal gradient caused by upwelling of hot asthenosphere. 相似文献
59.
北京社会极化与空间分异研究 总被引:95,自引:6,他引:95
本文论述了北京近年来经济体制改革和社会主义市场经济制度运行对城市社会结构的影响,尤其集中在:1.城市社会极化及其动力机制;2.新城市贫困现象及其原因;3城市社会空间分异及其人变化趋势等。 相似文献
60.
根据X射线衍射中θ扫描的基本原理,在理论分析的基础上认为θ曲线峰的形状能较精确地反映粘土矿物的定向水平和分层现象,而峰的积分面积比常规2θ曲线峰的积分面积更能客观地反映粘土矿物的含量。提出在粘土矿物X射线定量计算中用θ峰积分面积代替常规的2θ峰积分面积,并通过分析各粘土矿物的θ峰形了解样品中粘土矿物的分层情况 相似文献