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A generic framework (FW) for the monitoring and evaluation of spatially managed areas (here defined as marine areas subject to a planning and management regime) was developed and tested in nine marine areas of 13 European countries under the EU funded project MESMA (Monitoring and Evaluation of Spatially Managed Areas). This paper describes the lessons learned in the use of the FW and draws conclusions for its future use and development. The selected case studies represented diverse spatial scales, management status and complexity, ranging from sub-national areas to entire national coastlines, and large offshore regions. The application of the FW consisted of seven steps: starting with (i) context setting and (ii) gathering of relevant ecosystem information, human activities and management goals; it continues with (iii) indicator selection and (iv) risk assessment; and the final steps considers the (v) analysis of findings and (vi) the evaluation of management effectiveness, to end up with (vii) the revision and proposal of adaptation to current management. The lessons learnt through the application of the FW in the case studies have proved the value of the FW. However, difficulties rose due to the diversity of the nature and the different stages of development in planning and management in the case study areas; as well as, limited knowledge on ecosystem functioning needed for its implementation. As a conclusion the FW allowed for a flexible and creative application and provided important gap analyses.  相似文献   
63.
The recent years have witnessed a rise in interest in the ocean economy. To cover a more sustainable dimension, terms such as ‘blue economy’ and ‘blue growth’ have been coined, and are increasingly used in international contexts and academic literature. However, there are no generally accepted definitions of these ‘blue’ concepts. In particular, it is not clear what connotation of sustainability and what role of natural environment is linked to these terms. The objective of this study is to retrace the meaning of the concepts of blue economy and blue growth and include them in a coherent environmental accounting framework. Starting from the System of Environmental-Economic Accounting of the United Nations, a set of assumptions is proposed to link blue economy/growth and ecosystem services, including the creation of an adjusted measure of value added, while considering the depletion and degradation of the environment and the value of non-market benefits provided by the ecosystem. Finally, an example of this approach in the case of the Mediterranean Sea is presented.  相似文献   
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The Blue Nile Basin, situated in the Northwestern Ethiopian Plateau, contains ∼1400 m thick Mesozoic sedimentary section underlain by Neoproterozoic basement rocks and overlain by Early–Late Oligocene and Quaternary volcanic rocks. This study outlines the stratigraphic and structural evolution of the Blue Nile Basin based on field and remote sensing studies along the Gorge of the Nile. The Blue Nile Basin has evolved in three main phases: (1) pre‐sedimentation phase, include pre‐rift peneplanation of the Neoproterozoic basement rocks, possibly during Palaeozoic time; (2) sedimentation phase from Triassic to Early Cretaceous, including: (a) Triassic–Early Jurassic fluvial sedimentation (Lower Sandstone, ∼300 m thick); (b) Early Jurassic marine transgression (glauconitic sandy mudstone, ∼30 m thick); (c) Early–Middle Jurassic deepening of the basin (Lower Limestone, ∼450 m thick); (d) desiccation of the basin and deposition of Early–Middle Jurassic gypsum; (e) Middle–Late Jurassic marine transgression (Upper Limestone, ∼400 m thick); (f) Late Jurassic–Early Cretaceous basin‐uplift and marine regression (alluvial/fluvial Upper Sandstone, ∼280 m thick); (3) the post‐sedimentation phase, including Early–Late Oligocene eruption of 500–2000 m thick Lower volcanic rocks, related to the Afar Mantle Plume and emplacement of ∼300 m thick Quaternary Upper volcanic rocks. The Mesozoic to Cenozoic units were deposited during extension attributed to Triassic–Cretaceous NE–SW‐directed extension related to the Mesozoic rifting of Gondwana. The Blue Nile Basin was formed as a NW‐trending rift, within which much of the Mesozoic clastic and marine sediments were deposited. This was followed by Late Miocene NW–SE‐directed extension related to the Main Ethiopian Rift that formed NE‐trending faults, affecting Lower volcanic rocks and the upper part of the Mesozoic section. The region was subsequently affected by Quaternary E–W and NNE–SSW‐directed extensions related to oblique opening of the Main Ethiopian Rift and development of E‐trending transverse faults, as well as NE–SW‐directed extension in southern Afar (related to northeastward separation of the Arabian Plate from the African Plate) and E–W‐directed extensions in western Afar (related to the stepping of the Red Sea axis into Afar). These Quaternary stress regimes resulted in the development of N‐, ESE‐ and NW‐trending extensional structures within the Blue Nile Basin. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
66.
山东蓝宝石的宝石矿物学特征   总被引:6,自引:0,他引:6  
余晓艳 《岩矿测试》1999,18(1):41-45,49
对山东蓝宝石进行了系统的宝石矿物学研究,描述了山东蓝宝石的形态,大小,结构及包裹体特征,运用电子探针,粉晶X射线分析,顺磁共振光谱及化学全分析等测试手段,揭示了山东蓝宝石的成分,结构和物性之间的相互关系。  相似文献   
67.
纳米TiO2光催化降解亚甲基蓝   总被引:2,自引:0,他引:2  
在以钛酸丁酯为钛源,采用溶胶-凝胶法合成制备纳米TiO2催化剂样品的基础上,将其用于在紫外光照射和无光照射条件下进行亚甲基蓝降解的实验研究,并与P-25纳米TiO2进行光催化降解对比研究。对在不同条件下合成制备样品的光催化降解率的差异,通过X射线粉晶衍射、扫描电镜等从物相组成、微观结构等因素上进行了分析和探讨。结果表明,采用溶胶-凝胶法在450℃焙烧2 h所得到的纳米TiO2具有很好的光催化降解亚甲基蓝的能力,当催化剂样品质量浓度为2.5 g/L,亚甲基蓝初始浓度为5.0 mg/L时,室温下光催化反应3 h,其降解率达98%以上,其光催化降解率比P-25纳米TiO2高;光催化降解率与催化剂样品的制备条件、物相组成、颗粒尺寸等因素有关。  相似文献   
68.
区域经济建设与社会发展必须与地质环境保障能力相适应,地质环境保障能力的评价是涉及多层次、多因素作用的空间综合评价。在山东半岛蓝色经济区地质环境保障能力评价过程中,选取2个领域层、11个准则层、37个指标层指标建立评价体系,利用层次分析法确定各评价指标的权重,再以地理信息系统为基础进行图形的空间处理与叠加运算,进而按照确定的分级标准将地质环境保障能力分为强、较强、中等、较弱、弱5个等级。  相似文献   
69.
从光致发光光谱角度探讨了海南蓬莱蓝宝石的呈色机理.结果发现:与蓝宝石吸收光谱的500~700 nm吸收宽带相比,在500~720 nm发光波段内存在566.8 nm锐峰、600 nm左右肩峰和Cr~(3+)的694.2 nm特征峰.600 nm肩峰与其吸收峰镜像对称,566.8 nm处锐峰的产生原因复杂.600 nm肩峰可能与Fe~(2+)-Fe~(2+)离子对的电子跃迁有关;566.8 nm锐峰因532 nm激光激发Fe~(2+)-Ti~(4+)或Fe~(2+)-Fe~(3+)间的电荷迁移带,通过晶格造成Si~(4+)、Mg~(2+)等微量杂质离子敏化而产生.光致发光谱中呈现更多谱峰,能呈现离子跃迁时不同离子间发生的相互作用,为500~700 nm吸收宽带由不同致色机制的叠加给出了直接证明,是一种能全面地研究宝石矿物中致色元素能级结构的有效方法.  相似文献   
70.
RTK技术在东边道铁路定测中的应用   总被引:1,自引:0,他引:1  
通过对RTK技术在东边道铁路线路测量中的应用和探讨,并通过对RTK施放控制桩点后再经静态观测的解算值和控制桩点设计值的比较,阐述了RTK技术的高精度及可靠性,为将RTK技术在铁路线路测量中更好地得以应用和推广有着重要的意义和参考价值。  相似文献   
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