全文获取类型
收费全文 | 3184篇 |
免费 | 213篇 |
国内免费 | 45篇 |
专业分类
财政金融 | 105篇 |
工业经济 | 452篇 |
计划管理 | 803篇 |
经济学 | 775篇 |
综合类 | 303篇 |
运输经济 | 19篇 |
旅游经济 | 28篇 |
贸易经济 | 293篇 |
农业经济 | 215篇 |
经济概况 | 449篇 |
出版年
2024年 | 7篇 |
2023年 | 58篇 |
2022年 | 66篇 |
2021年 | 105篇 |
2020年 | 98篇 |
2019年 | 68篇 |
2018年 | 54篇 |
2017年 | 95篇 |
2016年 | 111篇 |
2015年 | 138篇 |
2014年 | 309篇 |
2013年 | 248篇 |
2012年 | 388篇 |
2011年 | 477篇 |
2010年 | 338篇 |
2009年 | 224篇 |
2008年 | 193篇 |
2007年 | 133篇 |
2006年 | 109篇 |
2005年 | 57篇 |
2004年 | 32篇 |
2003年 | 31篇 |
2002年 | 15篇 |
2001年 | 16篇 |
2000年 | 15篇 |
1999年 | 15篇 |
1998年 | 3篇 |
1997年 | 7篇 |
1996年 | 4篇 |
1995年 | 5篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 6篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 4篇 |
1983年 | 1篇 |
排序方式: 共有3442条查询结果,搜索用时 15 毫秒
41.
42.
This article explores the rhetoric of four energy transitions. It begins by summarising research on the intersection of fantasy, technology and the sociology of expectation. It then looks at how ideas of progress, modernity, cheapness, abundance and hope influence the way society perceives new energy technologies, causing them to overestimate benefits and underestimate challenges. Our rhetorical analysis finds in case studies of steam engines, gasoline automobiles, hydroelectric dams and nuclear reactors that newly ‘discovered’ sources of energy or newly invented technologies are always assumed to provide infinitely abundant energy and to have the potential to create positive utopian changes in society. We conclude by noting the salient implications of these rhetorical themes for energy planners, analysts and scholars. 相似文献
43.
Yulia Merkoulova 《期货市场杂志》2020,40(5):804-815
Using nonparametric methodology, I find that speculators are successful in taking profitable positions in energy futures markets, although the magnitude of this effect is lower than that found previously for agricultural markets. A plausible explanation for this difference is that price forecasting is more difficult for energy commodities. Moreover, I find that the energy speculators’ returns are due to the existence of the risk premiums rather than to speculators’ forecasting abilities. Futures risk premium is highly time-variant; notably, energy investors’ profits have been very limited in the GFC and post-GFC period, which coincided with the financialization of commodity markets. 相似文献
44.
Using an instrumental variable quantile regression technique, this paper assesses whether country risk and financial uncertainty exert an impact on energy commodity futures prices under different commodity conditional return distributions over the period from January 1994 to July 2017. We also discuss whether the correlations change with different dimensions of country risk, that is economic, financial, and political. The results reveal that country risk and financial stress do have a significant impact on energy commodity returns of futures contracts with different maturities, but their direction, intensity, and significance differ, caused by the distinct market situations and divergent channels of country risk. 相似文献
45.
The panel data analysis points to economic and social factors contributing to NOx, PM2.5, PM10, SO2, and VOCs in China’s 31 provinces. The spatial correlation analysis using Global and Local Moran’s I values indicates the existence of a significant and positive spatial autocorrelation with respect to environment, economy and energy, and the high spatial correlation is evident in the eastern region, covering the northern part of Yangtze River Delta, Huaihai Economic Zone, and the lower reaches of the Yellow River Economic Belt. The empirical estimation is performed through spatial lag and spatial Durbin models. All emitted air pollutants in 31 provinces have significant spatial dependence and strong spillover effects. There is an inverted U-shaped relationship between emitted air pollutants (NOx, PM10, VOCs, and PM2.5) and per capita GDP, which follows the EKC hypothesis. The relationship between SO2 and per capita GDP does not follow the EKC hypothesis. There is a positive relationship between pollutant emissions and coal consumption, which is consistent with current studies for various countries like Canada, Denmark, UK and US and regions like New York State. However, the effects of science and technology investment on air pollutants are mostly positive, which is not as policy expected. 相似文献
46.
[目的]文章对我国各地环境规制、产业结构与能源效率之间的关系进行研究,旨在更加真实地反映环境规制、产业结构与能源效率三者之间的关系,为各地政府早日实现环境保护、产业结构优化与能源效率多赢的局面提供参考依据。[方法]基于DEA方法测算了我国各地能源效率,将我国划分为高、中及低能源效率3个地区,构建了环境规制、产业结构与能源效率之间关系的模型,通过对2007—2016年我国30个省(市、区)的相关数据进行分析研究。[结果]在高效率地区内环境规制与能源效率两者显著为正,在中效率地区内两者也显著为正,而在低效率地区内两者则显著为负; 在高效率区域与中等效率区域内产业结构与能源效率两者关系显著为正,而在低等效率区域内两者关系不显著; 在高效率地区内环境规制与产业结构两者之间的协同作用显著,而在中等与低效率地区内两者之间的协同作用不显著。[结论]能源效率高与能源效率中等地区内环境规制与产业结构均正向影响能源效率,而能源效率低地区内环境规制与产业结构均负向影响能源效率; 能源效率高地区内环境规制与产业结构对能源效率的影响具有共同强化作用,而能源效率中等与能源效率低地区内环境规制与产业结构间协同效应不明显。 相似文献
47.
48.
The Sustainable Energy Authority of Ireland (SEAI) administers the Better Energy Homes scheme to provide a financial incentive for home owners to engage in energy efficiency retrofits. This study analyses data from the scheme and Building Energy Rating data for participants to the scheme to examine the value for money achieved by households. In addition, this research identifies which retrofit combinations provide greatest value for money, in terms of energy efficiency gains, for the grant provider. We utilize an error-in-variables approach to model the variation in benefits accruing to households of varying characteristics. We find that household and grant provider surplus can be maximized in the short term by retrofitting less energy efficient and larger homes, timber or steel frame homes and houses rather and apartments. The types of retrofits leading to the greatest surplus for both household and grant provider include cavity wall insulation paired with either a boiler with heating controls or heating controls only retrofit. 相似文献
49.
50.
能源碳排放与环境污染空间效应研究——基于能源强度与技术进步视角的空间杜宾计量模型 总被引:1,自引:0,他引:1
本文基于空间环境库兹涅茨曲线理论探讨经济发展约束下能源强度和技术进步对大气环境的空间效应作用机理,采用探索性空间分析工具、经典最小二乘估计(OLS)、空间滞后模型(SLM)、空间误差模型(SEM)和空间杜宾--可拓展随机性环境影响评估模型(Spatial Durbin-STIRPAT Models)探索能源碳排放与大气环境污染的空间格局和空间溢出效应。实证估计结果表明,能源碳排放与空气环境污染在空间分布上表现出空间正相关性和空间集聚效应;能源强度与技术进步对能源碳排放与大气环境的空间溢出效应显著。在此基础上提出了相应的政策建议。 相似文献