全文获取类型
收费全文 | 235篇 |
免费 | 12篇 |
国内免费 | 5篇 |
专业分类
测绘学 | 7篇 |
大气科学 | 66篇 |
地球物理 | 13篇 |
地质学 | 32篇 |
海洋学 | 13篇 |
综合类 | 2篇 |
自然地理 | 119篇 |
出版年
2023年 | 6篇 |
2022年 | 10篇 |
2021年 | 9篇 |
2020年 | 12篇 |
2019年 | 10篇 |
2018年 | 8篇 |
2017年 | 5篇 |
2016年 | 9篇 |
2015年 | 10篇 |
2014年 | 9篇 |
2013年 | 51篇 |
2012年 | 8篇 |
2011年 | 9篇 |
2010年 | 7篇 |
2009年 | 7篇 |
2008年 | 7篇 |
2007年 | 4篇 |
2006年 | 4篇 |
2005年 | 7篇 |
2004年 | 5篇 |
2003年 | 9篇 |
2002年 | 4篇 |
2001年 | 7篇 |
2000年 | 11篇 |
1998年 | 2篇 |
1997年 | 6篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1983年 | 1篇 |
排序方式: 共有252条查询结果,搜索用时 140 毫秒
161.
《Climate Policy》2013,13(5):494-515
A sectoral approach to GHG emissions reductions in developing countries is proposed as a key component of the post-2012 climate change mitigation framework. In this approach, the ten highest-emitting developing countries in the electricity and other major industrial sectors pledge to meet voluntary, ‘no-lose’ GHG emissions targets in these sectors. No penalties are incurred for failing to meet a target, but emissions reductions achieved beyond the target level earn emissions reduction credits (ERCs) that can be sold to industrialized nations. Participating developing countries establish initial ‘no-lose’ emissions targets, based upon their national circumstances, from sector-specific energyintensity benchmarks that have been developed by independent experts. Industrialized nations then offer incentives for the developing countries to adopt more stringent emissions targets through a ‘Technology Finance and Assistance Package’, which helps to overcome financial and other barriers to technology transfer and deployment. These sectorspecific energy-intensity benchmarks could also serve as a means for establishing national economy-wide targets in developed countries in the post-2012 regime. Preliminary modelling of a hybrid scenario, in which Annex I countries adopt economy-wide absolute GHG emissions targets and high-emitting developing countries adopt ‘no-lose’ sectoral targets, indicates that such an approach significantly improves the likelihood that atmospheric concentrations of CO2 can be stabilized at 450 ppmv by the end of the century. 相似文献
162.
《Climate Policy》2013,13(6):569-576
In contrast to many discussions based on annual emissions, this article presents calculations and projections of cumulative contributions to the stock of atmospheric CO2 by the major players, China, Europe, India, Japan and the USA, for the period 1900–2080. Although relative contributions to the climate problem are changing dramatically, notably due to the rapid industrialization of China, long-term responsibilities for enhanced global warming have not been transparently quantified in the literature. The analysis shows that if current trends continue, by the middle of this century China will overtake the USA as the major cumulative contributor to atmospheric concentrations of CO2. This has enormous implications for the debate on the ethical responsibilities of the major greenhouse gas emitters. Effective climate policy will require both the recognition of shared responsibility and an unprecedented degree of cooperation. 相似文献
163.
Abstract The UN Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol provide mechanisms for assisting less developed countries that are adversely affected by climate change. Such assistance would need a baseline, which ideally would set a precise date for specific impacts of climate change. This article presents the results of statistical tests that we carried out and, for the African region of the Sahel, finds that for precipitation (affecting food supply), impacts due to climate change can be ‘dated’ to the year 1967, when precipitation fell drastically, affecting the local food supply. Such a statistically robust benchmark would be useful to the Subsidiary Body for Scientific and Technological Advice (SBSTA) of the UNFCCC. The method illustrates how other baselines may be established for the important work of the SBSTA. 相似文献
164.
The ‘additionality’ criterion for the Clean Development Mechanism (CDM) (which is key to ensuring that CDM projects lead to real and additional emission reductions) has been a topic of much analysis and discussion. A number of different approaches, including those based on financial, barrier and market-penetration criteria, have been suggested as a test for additionality. A simple test for additionality is proposed that draws on the framework of the diffusion of innovations, especially the risk profile of adopters of new technologies or innovations. This approach has the potential to streamline the assessment for additionality, although it will require data on the rate of implementation of specific technologies or innovations. 相似文献
165.
梳理1992—2018年中亚五国碳排放变化过程,运用碳排放库兹涅茨曲线模拟人均碳排放与人均国内生产总值(GDP)的关系,基于中亚五国人均GDP、工业增加值、研发投入、自华进口中间品和资本品的技术溢出存量等指标,构建面板数据固定效应模型以探究碳排放影响机制。结果表明:(1) 中亚五国碳排放先降后升,各国碳排放的变化率波动较大,其中哈萨克斯坦碳排放占中亚五国碳排放比重最大。(2) 就人均碳排放与人均GDP拟合的碳排放库兹涅茨曲线关系而言,哈萨克斯坦和土库曼斯坦表现为倒N型,乌兹别克斯坦、塔吉克斯坦、吉尔吉斯斯坦和中亚五国表现为N型。(3) 中亚五国自华进口额呈现较快的增长趋势,其中自华进口的中间品和资本品合计约占自华进口总额的3.920%~10.976%,中亚五国整体及各国中间品技术溢出存量均明显大于资本品技术溢出存量。(4) 在影响中亚五国碳排放的诸多因素中,人均GDP和工业增加值占GDP比重的回归系数显著为正,人均GDP、工业增加值占GDP比重每上升1%,碳排放分别增加0.337%和0.343%,研发投入、交互项LnZJit×LnSit(中间品技术溢出存量的自然对数×工业增加值占GDP比重的自然对数)的回归系数显著为负,研发投入每增加1%,碳排放可减少约0.432%,在降低因工业增加值占GDP比重上升导致的碳排放方面,中间品技术溢出存量的影响极小。 相似文献
166.
科学判断一个国家在全球体系中的地位是制定外交政策的基础。目前中国的发展中国家地位遭到了西方国家的质疑,国内学者从国别比较等视角出发论证了中国的发展中国家地位,但缺乏从全球尺度分类视角的回应。论文基于多面体法、洛伦兹曲线分类法等方法,从经济、社会、环境、治理等方面构建经济体的多维发展水平分类指标体系和测度模型,将全球190个经济体划分成发达经济体Ⅰ~Ⅲ型、发展中经济体Ⅰ~Ⅴ型和过渡型经济体共9种类型,并探讨了不同类型经济体的发展水平特征、中国在全球经济体分类体系中的地位等问题。研究发现:① 不同类型经济体在经济、社会、环境、治理等分维度发展水平方面具有显著的差异性。② 发达经济体各维度发展水平排名普遍较高,总体呈现“并驾齐驱”特征;过渡型经济体在很多维度的发展指标与发达经济体Ⅲ型接近,多数经济体处于逐渐向发达经济体过渡的发展阶段;发展中经济体在分维度发展水平方面存在显著的结构性差异。③ 中国属于发展中经济体Ⅰ型类别,在全球190个经济体中排在第64位,在139个发展中经济体中排在第13位。④ 中国在全球经济体多维发展水平排序、各维度发展水平差异等方面具备发展中国家的普遍特征。该研究洛伦兹曲线分类法等方法的应用可丰富区域发展分类理论,相关结论可为回击西方国家对中国发展中国家地位的质疑提供借鉴。 相似文献
167.
基于修正的引力模型测算中国与周边国家的地缘经济关系,进而借助ArcGIS刻画地缘经济关系时空格局演化过程,以揭示其总体规律与特征。结果表明(:1)中国与周边国家地缘经济关系总体呈现出波动上升的态势,但国别间差异显著且逐渐扩大,并以2009年与2016年为转折点,将中国与周边国家双边地缘经济关系划分成缓慢发展期(2001—2008年)、平稳增长期(2009—2015年)和快速增长期(2016—2019年);(2)地缘经济关系总体上呈现东高西低的空间格局,即中国与东亚地区的日本和韩国为中-高至高地缘经济关系值,与西亚、南亚大多数周边国家主要为低至中-低地缘经济关系值。地缘经济关系格局演进的影响因素包括国际地缘环境、地缘经济利益、地缘区位、经济规模、资源要素禀赋、地缘文化等。 相似文献
168.
169.
建立衡量人才、技术、宽容、政府政策及基础设施4个因素的指标体系,分析其对G20国家创意产业发展的影响程度。研究结果表明:1 4个因素综合排名前3位的国家是美国、德国、加拿大。其中,人才发展方面,美国、韩国、澳大利亚优势明显;技术方面,韩国、日本、德国得分居高;宽容方面,澳大利亚、加拿大及欧盟位列前3位;政府政策及基础设施方面,德国、日本、美国居于前列。2 4个因素对G20国家创意产业的发展都具有显著正向影响,其中技术和人才因素对创意产业发展影响最大;3 Florida的3T理论具有一定的局限性,忽视了政府政策及基础设施条件对创意产业发展的重要作用。 相似文献
170.
We analyze and contrast how China and India mobilized financial resources to build domestic technological innovation systems in wind energy. To that end, we identify distinct stages of technology diffusion in the two countries in the period 1986–2012, and analyze the interplay between public policies and the development of the technological innovation system across the different stages. We show that the two countries’ distinct development strategies for wind energy – China developed wind energy largely through its state-owned enterprises, while India opened up wind energy investment to the private sector in the early 1990s – influenced system outcomes in terms of technology diffusion, domestic industry structure, competitiveness, and ownership. By unraveling the interplay between public policies, investment risks and returns, and actor characteristics, we explain the differences in system outcomes and identify important policy trade-offs between the two strategies. Our analysis provides novel insights about the process of financial resource mobilization in technological innovation systems, the dynamics of innovation-system growth, and the policy trade-offs that must be reconciled by countries that aim to promote the diffusion of a particular technology. 相似文献