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采用镜下观察、激光剥蚀电感耦合等离子体质谱、紫外-可见吸收光谱等观察测试方法,对缅甸和莫桑比克红宝石的常规宝石学、包裹体、化学元素含量及紫外光谱特征进行了系统的对比研究。结果表明,缅甸红宝石在紫外荧光灯下呈现较强的红色荧光,内部含有互为60°夹角定向排列的短针状金红石、"糖浆状"构造等特征包裹体,具有低Fe、高V、高Ga的微量元素特征,紫外区吸收截止边小于320 nm,且694 nm处的荧光较强。莫桑比克红宝石在紫外荧光灯下荧光较弱,内部可见双晶面、无序排列的金红石和角闪石晶体等特征包裹体,具有高Fe、低V、低Ga的微量元素特征,紫外区吸收截止边在350 nm附近。上述性质可用作区分缅甸和莫桑比克红宝石的标志性识别特征。  相似文献   
3.
The concept of resilience has emerged out of a complex literature that has sought to make sense of an increasingly interconnected world that appears ever more beset by crises. Resilience’s appeal is reflected by the burgeoning mass of literature that has appeared on the subject in the past five years. However, there is ongoing debate surrounding its usage, with some commentators claiming that the term is inherently too conservative a one to be usefully applied to situations of vulnerability in which more radical social change is required. This article extends existing efforts to formulate more transformative notions of resilience by reframing it as a double-edged outcome of the pre-reflective and critical ways in which actors draw upon their internal structures following the occurrence of a negative event, thus reproducing or changing the external structural context that gave rise to the event in the first place. By employing a structuration-inspired analysis to the study of small-scale farmer responses to a flood-induced resettlement programme in central Mozambique, the article presents a systematic approach to the examination of resilience in light of this reframing. The case study findings suggest that more attention should be paid to the facilitative, as well as constraining, nature of structures if vulnerable populations are to be assisted in their efforts to exert transformative capacity over the wider conditions that give rise to their difficulties.  相似文献   
4.
滨海砂矿是目前全球最大的潜在海洋矿产资源之一,仅次于石油与天然气。莫桑比克东部沿海滨海砂矿资源丰富,在世界上占有重要地位。该文结合莫桑比克赞比西亚省5004C矿区锆钛砂矿,分析矿石结构与构造、矿石物质组成、矿物含量及变化等矿石质量特征,为莫桑比克东部沿海锆钛砂矿的勘探和开发提供有利信息。  相似文献   
5.
莫桑比克楠普拉省喀祖祖地区多条河流均有人工砂金开采活动.砂金分布在海拔300~450 m之间的石英砾石层,底部岩石主要为中元古代片麻状杂岩体.研究区为准平原-丘陵地貌,水动力条件受季节影响较大.砂金分布与河流不存在明显的耦合性,暗示了原生金矿化可能较分散.同时,研究区露头受第四纪覆盖严重,物化探效果不显著,砂金与重砂矿物组合因而成为重要的原生金找矿标志.结合双目镜观察及扫描电镜分析得出,与砂金密切相关的重砂矿物包括黄铁矿、钛铁矿、锆石等.砂金颗粒多呈棱角状,部分可观察到残留连生矿物,整体暗示了近源堆积的特征.根据电子探针分析结果,不同部位产出砂金成分相近,表现为较高的金成色(w(Au)均高于98%)及较低的微量元素(仅含少量Fe、Cu),暗示为同一构造背景下的产物.综上,莫桑比克楠普拉省喀祖祖地区原生金矿化可能是与黑云斜长片麻岩(及其长英质脉体)相关的低硫型热液金矿化,形成背景为泛非期造山运动.  相似文献   
6.
This article summarizes findings from a research project on junior farmer field and life schools (JFFLS) as an agriculture‐based intervention to improve the livelihood prospects of children and orphans made vulnerable by HIV/AIDS in central Mozambique. In the sites investigated JFFLS have opened up concrete present and potential livelihood options in agriculture and beyond. More generally, the resource profile dynamics of participants are altered in ways that provide strong grounds to believe that the skills and knowledge they have gained will positively impact the trajectories of their future lives. In terms of HIV/AIDS mitigation, the findings recommend livelihood‐based interventions aimed at altering the vulnerability context of specific population groups.  相似文献   
7.
Despite the distribution of dugongs Dugong dugon ranging across nearshore waters of the tropical and subtropical regions of the Indian Ocean and western Pacific Ocean, their distribution in the western Indian Ocean is highly fragmented and appears to be declining. The population of the Bazaruto Archipelago is believed to comprise the only viable population in the region. In all, 27 surveys were flown over the Bazaruto Bay area to define the distribution and estimate the abundance of the species in the area. A total of 9 052 nautical miles of survey effort was flown during the surveys, from which there were 355 sightings of 760 dugongs. Two core areas of distribution were apparent within the surveyed area; a northern core area spread within the 10 m isobath between the Save River mouth and Ponta Bartolomeu Dias (21°24′S), and a southern core area aligned with the shallow sandbanks to the north and south of Santa Carolina Island. Group sizes recorded in the Bazaruto Archipelago were comparable to group sizes recorded in other regions where dugongs occur, although few large (>20) groups of dugongs were seen in this study. Line transect analyses of each survey showed dugong densities were considerably lower than densities recorded in surveys in Australian waters or in the Arabian Gulf, with a population estimate of 247 dugongs (CV = 34.1) when all surveys were considered, and 359 dugongs (CV = 38.2) when only the surveys that were carried out under adequate sighting conditions were included.  相似文献   
8.
Natural resource-dependent societies in developing countries are facing increased pressures linked to global climate change. While social-ecological systems evolve to accommodate variability, there is growing evidence that changes in drought, storm and flood extremes are increasing exposure of currently vulnerable populations. In many countries in Africa, these pressures are compounded by disruption to institutions and variability in livelihoods and income. The interactions of both rapid and slow onset livelihood disturbance contribute to enduring poverty and slow processes of rural livelihood renewal across a complex landscape. We explore cross-scale dynamics in coping and adaptation response, drawing on qualitative data from a case study in Mozambique. The research characterises the engagements across multiple institutional scales and the types of agents involved, providing insight into emergent conditions for adaptation to climate change in rural economies. The analysis explores local responses to climate shocks, food security and poverty reduction, through informal institutions, forms of livelihood diversification and collective land-use systems that allow reciprocity, flexibility and the ability to buffer shocks. However, the analysis shows that agricultural initiatives have helped to facilitate effective livelihood renewal, through the reorganisation of social institutions and opportunities for communication, innovation and micro-credit. Although there are challenges to mainstreaming adaptation at different scales, this research shows why it is critical to assess how policies can protect conditions for emergence of livelihood transformation.  相似文献   
9.
The quest for direct lines of evidence for Paleolithic plant consumption during the African Middle Stone Age has led scientists to study residues and use-wear on flaked stone tools. Past work has established lithic function through multiple lines of evidence and the spatial breakdown of use-wear and microscopic traces on tool surfaces. This paper focuses on the quantitative analysis of starch assemblages and the botanical identification of grains from flake and core tools to learn about human ecology of carbohydrate use around the Niassa woodlands, in the Mozambican Rift. The processing of starchy plant parts is deduced from the occurrence of starch assemblages that presumably got attached to stone tool surfaces by actions associated with extractive or culinary activities. Specifically, we investigate starch grains from stone tools recently excavated in northern Mozambique at the site of Mikuyu; which presumably spans the middle to late Pleistocene and represents similar sites found along the Malawi/Niassa corridor that links East, Southern, and Central Africa. Starch was extracted and processed with a diverse tool kit consisting of scrapers, cores, points, flakes, and other kinds of tools. The microbotanical data suggests consumption of seeds, legumes, caryopses, piths, underground storage organs, nuts, and mesocarps from more than a dozen families. Our data suggest a great antiquity for starch use in Africa as well as an expanded diet and intensification.  相似文献   
10.
Marcus Power 《Geoforum》2009,40(1):14-24
One important (though often neglected) part of the ‘development business’ committed to principles of partnership is the Commonwealth, a voluntary association of 54 independent countries, almost all of which were formerly under British rule. This paper focuses on the Commonwealth’s contemporary sense of ‘responsibility’ for shaping African development through ‘partnership’ and by promoting ‘good governance’ and examines the particular example of Mozambique, which joined the Commonwealth in 1995. In exploring exactly what membership of this post-colonial ‘family’ has meant for Mozambique the paper explores the neocolonial paternalism and sense of trusteeship that the Commonwealth has articulated in its often very apolitical vision of African development which seems to lock the continent into a permanent stage of tutelage and to repetitively reduce Africa to a set of core deficiencies for which externally generated ‘solutions’ must be devised. More generally, the paper also examines the wider context of the Commonwealth’s involvement in Africa by looking at the connections it has made to British industry, British charities and the British Department for International Development (DFID). The paper concludes with an assessment of the ‘showcase’ potential of Mozambique and its importance to Commonwealth and DFID narrations of an African ‘success’ story of peace, stability and growth since the end of the country’s devastating civil war in 1992.  相似文献   
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