首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   309篇
  免费   17篇
测绘学   5篇
大气科学   34篇
地球物理   76篇
地质学   113篇
海洋学   24篇
天文学   44篇
综合类   1篇
自然地理   29篇
  2023年   5篇
  2022年   4篇
  2021年   9篇
  2020年   14篇
  2019年   15篇
  2018年   13篇
  2017年   23篇
  2016年   29篇
  2015年   26篇
  2014年   15篇
  2013年   23篇
  2012年   17篇
  2011年   24篇
  2010年   10篇
  2009年   19篇
  2008年   10篇
  2007年   14篇
  2006年   13篇
  2005年   9篇
  2004年   8篇
  2003年   5篇
  2002年   5篇
  2000年   3篇
  1999年   3篇
  1998年   2篇
  1997年   1篇
  1996年   1篇
  1995年   3篇
  1990年   1篇
  1984年   1篇
  1981年   1篇
排序方式: 共有326条查询结果,搜索用时 31 毫秒
71.
72.
73.
The Paris Agreement heralds a new era in international climate governance. Yet, the Agreement's implementation rulebook is still under negotiation. During this transition, from the Kyoto Protocol to the new regime under the Paris Agreement, many non-state actors are facing a high level of uncertainty. In particular, actors in the voluntary carbon market are struggling to define their new role. The business model of producing carbon credits in developing countries and selling them elsewhere is threatened. Although its financial significance and achieved emission reductions are limited, the voluntary market's role as an incubator for innovation has made it a prominent representative of non-state mitigation mechanisms. Therefore, we ask: What effects will the regime change to the Paris Agreement have on the voluntary carbon offset market (VCM) and how does it react to these effects?

This study analyses perceptions of, and reactions to, the new regulatory environment within the VCM. We apply the Discursive Agency Approach to scrutinize the institutions, discourses and influential agents involved in the VCM, and the strategic practices they apply to manage the transition towards the Paris regime. We find two dominant coping strategies: to align the voluntary offsetting mechanism with the Paris Agreement, and to re-invent its overall purpose as a tool to deliver sustainable development rather than solely emission reductions. Based on these results, we outline ‘thought spaces’ for a future VCM: (1) voluntary and non-party offsetting beyond nationally determined contributions (NDCs), (2) results-based financing for emission reductions and sustainable development, and (3) private climate action under international oversight.

Key policy insights
  • The Paris Agreement threatens the VCM's business model, prompting market agents to frame and legitimize their work in new ways.

  • The voluntary market's viability depends on the future accounting rules for emission reductions under Paris Agreement Article 6. Discursive struggles surround the risks of double counting and NDC ambitions.

  • Based on an understanding of the past, we can draw lessons from agents’ attempts to re-legitimize their role under the new Paris Agreement; their future visions will shape the debates about this nascent regime.

  相似文献   
74.
Sebastian  A.  Bader  D. J.  Nederhoff  C. M.  Leijnse  T. W. B.  Bricker  J. D.  Aarninkhof  S. G. J. 《Natural Hazards》2021,109(3):2343-2362
Natural Hazards - As demonstrated by recent tropical cyclone events, including U.S. Hurricanes Harvey, Irma, and Maria (2017), and Florence (2018), the destructive potential of flooding driven by...  相似文献   
75.
76.
Sediment detention basins are implemented on mountain rivers to trap solid material that may aggravate the flooding of downstream settlements.However,retention structures built in the past may unnecessarily retain sediment during non-hazardous flood events,resulting in high maintenance costs and sediment deficit downstream.In addition,the so-called spontaneous self-flushing of previously retained sediment during floods has occasionally been observed.Recent research suggests to design sediment detention basins for controlling sediment passage with a guiding channel across the deposition area upstream of a hybrid barrier.Such barriers consist of a check dam with a slot orifice and an upstream bar screen with a bottom clearance in order to benefit from a combined mechanical-hydraulic retention control.The present paper enhances this pioneering research with the help of new experimental data,including a wide range of sediment mixtures and large wood,as well as variable barrier heights.Improved design criteria are provided regarding the bar screen and the basin storage capacity.The functionality of the enhanced concept for sediment detention is illustrated by a case study on a physical model:the protection of the Villard-Bonnot village(France)against torrential hazards.  相似文献   
77.
We present an overview of the Space Telescope A901/2 Galaxy Evolution Survey (STAGES). STAGES is a multiwavelength project designed to probe physical drivers of galaxy evolution across a wide range of environments and luminosity. A complex multicluster system at   z ∼ 0.165  has been the subject of an 80-orbit F606W Hubble Space Telescope (HST) /Advanced Camera for Surveys (ACS) mosaic covering the full     span of the supercluster. Extensive multiwavelength observations with XMM–Newton , GALEX, Spitzer , 2dF, Giant Metrewave Radio Telescope and the 17-band COMBO-17 photometric redshift survey complement the HST imaging. Our survey goals include simultaneously linking galaxy morphology with other observables such as age, star formation rate, nuclear activity and stellar mass. In addition, with the multiwavelength data set and new high-resolution mass maps from gravitational lensing, we are able to disentangle the large-scale structure of the system. By examining all aspects of an environment we will be able to evaluate the relative importance of the dark matter haloes, the local galaxy density and the hot X-ray gas in driving galaxy transformation. This paper describes the HST imaging, data reduction and creation of a master catalogue. We perform the Sérsic fitting on the HST images and conduct associated simulations to quantify completeness. In addition, we present the COMBO-17 photometric redshift catalogue and estimates of stellar masses and star formation rates for this field. We define galaxy and cluster sample selection criteria, which will be the basis for forthcoming science analyses, and present a compilation of notable objects in the field. Finally, we describe the further multiwavelength observations and announce public access to the data and catalogues.  相似文献   
78.
Climate change and violent conflict in Europe over the last millennium   总被引:1,自引:0,他引:1  
We investigate the relationship between a thousand-year history of violent conflict in Europe and various reconstructions of temperature and precipitation. We find that conflict was more intense during colder period, just like Zhang et al. (Clim Change 76:459–477, 2006) found for China. This relationship weakens in the industrialized era, and is not robust to the details of the climate reconstruction or to the sample period. As the correlation is negative and weakening, it appears that global warming would not lead to an increase in violent conflict in temperature climates.  相似文献   
79.
80.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号