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301.
基于海洋产业结构理论,总结了我国海洋产业结构的发展趋向,分析了海域资源配置与海洋产业结构的关联,以及海洋产业结构对海域资源配置的影响。研究表明,我国海洋产业结构相对协调,但海洋传统产业占海洋产业的比重较高。在海域资源配置的过程中,应在发挥传统海洋产业优势的同时,积极引导新兴海洋产业的发展。  相似文献   
302.
历史廉政文化资源形态绚丽多彩,内涵丰富,是建设社会主义廉政文化的重要元素。利用历史廉政文化资源进行廉政文化建设,具有独特的意义和效果。雷州文化发源于雷州半岛,以其历史悠久、底蕴深厚而跻身于广东四大区域文化之一,也孕育着深厚的历史廉政文化,这是湛江人民历来用以传承传统、进行廉政教育的宝贵精神财富和德育资源。湛江人民在利用历史廉政文化资源深化廉政文化建设的实践中所创立的经验和理论值得人们思考和借鉴。  相似文献   
303.
松辽盆地晚白垩纪青山口组和嫩江组蕴藏着丰富的油页岩资源,已查明4处超大型中浅层油页岩矿床,盆地油页岩资源整体呈现"局部查明程度高、整体认识程度低"的特征。本文采用以地质类比法为主、统计算法为辅的统计类比法估算油页岩潜在资源量。在松辽盆地嫩江组探明的超大型矿床——吉林松南油页岩含矿区的类比刻度区内,以松辽盆地油页岩成矿富集条件为理论依据,优选出控制油页岩成矿富集的3个一级和6个派生二级地质因素来建立类比参数库,并提出"多态"定性变换原则处理类比参数。采用特征因子法确定刻度区与预测区的相似类比系数概率分布函数,并构建了油页岩资源体积丰度概率分布函数,从而利用蒙特卡罗法和组合抽样法计算不同置信水平下的油页岩潜在资源量。提出利用"高概率值波动剧烈"选取原则评价概率区间上合理的油页岩潜在资源量,把100%~85%概率区间的资源量作为松辽盆地嫩江组油页岩资源评价的合理值区间。结果显示,松辽盆地嫩江组中浅层油页岩在合理概率下的潜在资源量分别为2867.2×108 t(100%)、3356.2×108 t(95%)、3834.0×108 t(90%)、4307.7×108 t(85%),合理概率区间上的平均资源量为3591.3×108 t。验证分析表明,统计类比法对大范围低勘探程度的预测区资源估算更为准确,填补了中—低勘探盆地油页岩在资源评价方面的不足,可以为其他同类型沉积盆地的能源或矿产资源评价起到借鉴作用。  相似文献   
304.
The expansion of resource extractivism in Latin America in the last decade has been related to previous neoliberalisation processes, which opened-up mineral exploitation to transnational firms and granted investors favourable conditions. Extractivism, however, expanded equally (or more) in countries which have undertaken “counter-neoliberal” reform—as it is most clearly the case for Evo Morales’s Bolivia. Building on regulationist approaches and strategic-relational state theory, this paper analyses recent changes in the governance of Bolivian mining. It contributes to understanding how and why the Morales governments’ objectives to initiate a transition towards a more plural and diversified economy—informed by social movements—have not been achieved to date. We make three interrelated claims. First, the expansion of mining has been enabled by the maintaining of institutional arrangements for mineral exploitation established during neoliberalism, favouring transnational firms and self-employed (“cooperative”) miners over state-owned and community-managed operations. Second, despite the new government’s improved legal framework for the promotion of environmental and indigenous rights, the mining sector has continued to benefit from de facto lax environmental regulation, which constitutes an indirect incentive to expansion at the expense of ecologies and indigenous–peasant livelihoods. Third, the state has played a central role in weakening social resistance to mining expansion, by demobilising those social forces—particularly peasant–indigenous organisations—whose proposals and demands conflicted most clearly with extractivist development. We suggest, therefore, that analysing changing state–society relations is central to understanding the counter-neoliberalisation of resource governance and its limits.  相似文献   
305.
Concerns about future supplies of raw materials demand careful examination of underlying assumptions and data. Flawed deposit information, ignored undiscovered resources and questionable assumptions about future consumption require a new look at copper resources.A careful compilation of 1978 copper-bearing mineral deposits totals 2700 million metric tons of copper including past production—considerably more than reported in previous studies. About 69% of the copper is in porphyry copper deposits and 12% in sediment-hosted copper, Magmatic sulfide (mostly intrusive Ni) deposits account for 5.1%, and IOGC adds about 4.7%. VMS deposits represent 45% of the 1978 deposits but only 4.9% of the copper.The largest 20% of the deposits account for over 92% of the total copper metal. In other words, total Cu content in the smaller 1600 deposits is only about 8% of all Cu known in all deposits. This is a consequence of highly skewed frequency distributions of deposit tonnages and contained metals in all kinds of mineral deposits. This relationship is critical if one is concerned about long-term supply of copper. Typically, distributions of contained metal can be modeled well by the lognormal distribution for individual types of deposits.Information used here and in many other studies on copper includes past production. Total past production through 2015 is about 667 million tons Cu. After subtracting past production from the total copper in known deposits, the remaining unproduced copper from known deposits is 2030 million tons. Known deposits inform us about undiscovered copper resources.Over 80% of known copper is in porphyry copper and sediment-hosted copper deposits. A reliable and robust USGS managed global assessment of 225 tracts for porphyry Cu and sediment-hosted Cu produced an expected value estimate of 3500 million tons Cu in undiscovered deposits. Deposit types not assessed such as IOGC are likely to have significant amounts of undiscovered copper. If the proportion of total Cu accounted for by the two major deposit types assessed is the same proportion in all undiscovered deposits, total Cu expected in these other deposit types would add an additional 850 million tons. The reasonable estimate of copper in undiscovered mineral deposits of 4350 million tons when added to the unmined 2030 million tons in known deposits provides an estimate of 6380 million of tons Cu, which far exceeds estimates published by other researchers.Growth in copper production appears to be exponential over time but appears to be linear with respect to population. Demand for copper is not driven by time, but rather by population and per capita income. Rates of population increases are slowing and incomes in many countries are increasing. Per capita consumption of copper will increase over the coming years as populous nations such as China and India develop increasing per capita incomes, but the demand will likely level off as their economies improve. The large estimated copper resources along with evidence of slowing demand for copper over the long term considerably extend the time of “peak copper” and the long mine life of large deposits means the decline in production after will not be rapid. The focus of copper supply concerns should be on important problems such as improving recovery rates, careful consideration of the benefits and costs of mining very large deposits, technologies to increase exploration success in covered areas and reducing costs of underground mining.  相似文献   
306.
地质体组合构造分析方法与找矿   总被引:2,自引:0,他引:2  
地质体组合构造分析方法是在地质体形态分类基础上,根据地质体结构的不均衡性所引起的变形和矿化的差异,遵循构造分析的基本原理,对各类地质体的变形机制和破裂形成规律作了初步总结,较系统地归纳了层状地质体的变形规律,是一套全新的构造研究方法。在找矿应用方面,提出了以破裂为导向的后生矿床找矿思维,根据地质体及其组合中的破裂变形规律,可快速评估矿区的资源潜力,在指导找矿方向、判断找矿标志等方面,具有较强的较强的实用性,并具有易掌握、可操作性强、研究周期短等特点。该方法的提出丰富了构造地质学和矿床学的研究方法,具有一定的理论意义。  相似文献   
307.
Resource conflict is a common feature of coastal management. This conflict is often managed by using spatial planning tools to segregate uses, with access decisions made through a comparison of the economic costs and benefits of the competing sectors. These comparisons rarely include an in-depth analysis of the extent or nature of the conflict. One commonly experienced form of resource conflict in coastal communities involves professional fishing, recreational fishing and broader coastal tourism. In New South Wales, Australia the professional fishing industry is often seen as being in conflict with recreational fishing and tourism, and there are frequent calls to close areas to professional fishing, arguing that this will provide improved economic benefits to local communities. This research examined the relationships between the three sectors using economic valuations, qualitative interviews and a large-scale representative questionnaire of the general public. The results revealed highly interconnected and mutually supportive relationships, with professional fishing providing a range of services that benefit both tourism and recreational fishing. These results suggest that spatial management exercises that seek to segregate or remove one sector from an area, may be counterproductive to the interests of all these groups. Relying on economic valuations of each sector as if they stand alone is insufficient to adequately understand their roles in local communities. Resource allocation decisions should be based on evaluations that consider the interconnections between sectors, and consider whether negotiated sharing of resources may provide greater community benefits than excluding certain groups of users.  相似文献   
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