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531.
The Chopf Member is a glauconitic, phosphate-bearing succession that occurs in the distal part of the Helvetic Alps (eastern Switzerland). The recent discovery of age-diagnostic ammonites within this horizon allows for its attribution to the lower part of the Gerhardtia sartousiana zone (middle Late Barremian). This new age corresponds to a maximal age for the onset of the Schrattenkalk Fm. in this area, and is coeval with the onset of the Urgonian facies in other parts of the western Tethyan realm. This new age allows also for a more precise dating of Late Barremian δ13C curves. To cite this article: S. Bodin et al., C. R. Geoscience 338 (2006).  相似文献   
532.
Carbonate δ13C values provide a useful monitor of changes in the global carbon cycle because they can record the burial ratio of organic to carbonate carbon. The most pronounced isotope excursions in the geologic record occur during the Neoproterozoic and have assumed a central role in the interpretation of biogeochemical events preceding the Ediacaran and Cambrian radiations. The most profound negative carbon isotope excursion is best recorded in the Ediacaran-aged Shuram Formation of Oman and has potential equivalents worldwide including the Wonoka Formation of South Australia and other sections in China, India, Siberia, Canada, Scandinavia and Brazil. All these excursions are less well understood than those in the Phanerozoic because of their unusual magnitude, long duration (> 1 Ma) and the difficulty in correlating Neoproterozoic basins to confirm independently that they do indeed record global change in the mixed ocean reservoir. Alternatively, these δ13C anomalies could reflect diachronous diagenetic processes. Currently none of these excursion are firmly time constrained and critical to their interpretation is a coherent reproducibility and synchroneity at the global ocean scale. Here we use available strontium isotope record as an independent chronometer to test the timing and synchroneity of the Shuram δ13C and its potential equivalents. The use of the 86Sr/87Sr ratio allows the reconstruction of a coherent, global δ13C record calibrated independently against time. The calibrated δ13C curve indicates that the Shuram negative anomaly spans several tens of millions of years and reaches values below −10‰. This carbon isotopic anomaly therefore represents a meaningful oceanographic event that fundamentally challenges our understanding of the carbon cycle as defined in the Phanerozoic.  相似文献   
533.
Abstract

The future role of carbon sinks with reference to the Kyoto Protocol depends significantly on developing an international consensus on carbon-sink assessment and carbon accounting. A clear and practical approach is needed that allows both the scientific community and policy-makers to construct a viable operational framework. This article proposes that a new strategy be developed for carbon-sink assessment based on full carbon accounting (FCA) alongside a separate political tool for carbon accounting. This approach is derived from the experience of the European critical loads (CL) concept, which seeks to quantify levels of pollutants (such as sulfur) that can be absorbed by the environment without causing ecological harm. Crucial to the implementation of such a strategy are robust institutional settings, such as an internationally coordinated monitoring system, open and fair access to the assessment processes, and international research cooperation programs for addressing associated problems of carbon-sink activities.  相似文献   
534.
The Low-Carbon Society (LCS) research project (Strachan et al., 2008) is to be congratulated for providing a rich, useful source of models to inform and precipitate discussion of policy options for moving towards a low-carbon society. This commentary explores additional considerations that warrant inclusion in any policy discussion: the feasibility of political will and leadership, the limitations of technical feasibility, and clarity about what ‘the price of carbon’ means. Difficulties exist with establishing carbon prices due to differences in energy prices between countries and the distinction between baseline (existing policies) and additional parts. An alternative may be to place more emphasis on the energy price for mitigation, along with other indicators (energy efficiency, carbon intensity, renewable power diffusion) for comparison. A policy is proposed, based on the energy price combined with an emphasis on accelerating technological innovation and overcoming barriers to the adoption of energy efficiency measures.  相似文献   
535.
《Climate Policy》2013,13(2-3):161-177
Abstract

US President Bush repudiated the Kyoto Protocol because, in his view, it is ‘fatally flawed in fundamental ways’. This paper evaluates seven proposals to redress the protocol according to their potential to deal with three key issues that have reinforced US intransigence: hot air, cost uncertainty and developing country participation. It argues that negotiations on intensity targets hold the most promise. Because intensity targets limit hot air, but do not limit economic growth, and a high variance of carbon intensity exists among countries with similar GDP per capita, intensity targets based on best practice levels might be agreeable to developing countries and the US. If a protocol specifying such targets were implemented, less warming would be associated with larger world GDP than would otherwise be the case, and countries' carbon intensity and emissions per capita would tend to converge to best practice levels at every stage of development.  相似文献   
536.
《Climate Policy》2013,13(1):77-88
Abstract

The UK climate change programme has introduced a range of instruments to foster investment in low carbon technologies and markets. We estimate the total value of these interventions, in terms of the redirection of financial flows and directly foregone tax income, to be about £1.3 billion per year (c. Euro or US$ 2 billion per year), as from 2002 to 2003 when the renewable obligation certificates (ROCs) first take effect. About 20% of this consists of direct expenditure, the remaining 80% is in the form of indirect expenditures contained within sectors (ROCs, the energy efficiency commitments), and foregone tax revenues. Most of the energy-efficiency investment is estimated to recoup expenditure within normal life-cycles and may thus be considered profitable; the profitability of the supply-side interventions is predicated mostly upon expected cost reductions associated with the build up of the associated industries.  相似文献   
537.
More and more organizations are compensating the greenhouse gas emissions caused by their products and services through carbon offset programs. From the customers’ perspective, the mitigation of negative externalities associated with their demand may increase the utility derived from the (then guilt-free) consumption. In particular in settings where consumers do not pay for the marginal cost of consumption, this may lead to higher levels of resource use. This article empirically examines how the announcement of an organizational carbon offset program affects consumption in a CO2-intensive everyday activity (showering). We further evaluate the provision of real-time feedback as a strategy to counteract potential increases in consumption. For this purpose, we conducted an eight-week randomized controlled natural field experiment in a German youth hostel (full 2 × 2 factorial design; N = 9,999 observations). Consumption in the group with the offset program was statistically significantly higher than in the control group (by 5.4 to 15.5%). However, participants who additionally received real-time feedback on their consumption did not increase their resource use compared to the control group. While the results suggest that carbon offset programs may increase resource use, the findings provide evidence that organizations can counteract these adverse effects by making the individual’s resource use salient.  相似文献   
538.
2017年底中国全国碳市场启动,全球正式运行的碳排放权交易体系达到21个。伴随碳排放权交易的广泛开展,加之产品市场不确定性的冲击,控排企业的违约行为也日益多样化和复杂化。基于此,根据中国碳市场试点地区的通行交易规则,通过在产品市场中引入随机冲击,分析在具有储蓄机制且存在不确定性需求的碳交易体系中,企业违约行为的方式以及监管强度对企业违约行为的影响。研究结果表明:抽查比例较高的强监管设置下被试不会产生系统动机来排放违约,弱监管设置下明显的报告违约会导致排放总量上升。即使面临不确定性冲击,储蓄机制依然能促进控排企业以一个相对有效的方式跨期分配生产量。因此给出如下建议:违约处罚应该分级,报告违约处罚力度应大于排放违约;为提高实际履约率,各地应提高排放报告抽查比例;完善配额储蓄机制。  相似文献   
539.
推动电力行业低碳发展是中国有效控制CO2排放和推动尽早达峰的重要抓手。在分别利用学习曲线工具和自下而上技术核算方式分析风电、光伏两类主要的可再生电力和其他各类电源发展趋势的基础上,综合评估了既有政策和强化政策条件下2035年前中国电力行业能源活动碳排放变化趋势。研究发现,既有政策情景下电力行业碳排放在2030年左右达到峰值,届时非化石能源在发电量中比重为44%,而通过强化推动能源绿色低碳发展的相关政策,2025年前即可达到电力行业碳排放峰值,2030年非化石电力在发电量中比重可以提升至51%,其中可再生电力加速发展将分别贡献2025、2030和2035年当年减排量(相对于既有政策情景)的45%、54%和62%。尽管从保障电力稳定安全供应角度,煤电装机仍有一定增长空间,但考虑到电力行业绿色低碳和可持续发展的长期需求,仍应加强对煤电装机的有效控制,“十四五”期间努力将煤电装机控制在11亿kW左右的水平。  相似文献   
540.
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