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   1807篇
  免费   47篇
  国内免费   4篇
财政金融   97篇
工业经济   443篇
计划管理   484篇
经济学   228篇
综合类   64篇
运输经济   4篇
旅游经济   5篇
贸易经济   224篇
农业经济   153篇
经济概况   156篇
  2024年   6篇
  2023年   24篇
  2022年   32篇
  2021年   54篇
  2020年   71篇
  2019年   44篇
  2018年   39篇
  2017年   35篇
  2016年   56篇
  2015年   57篇
  2014年   136篇
  2013年   164篇
  2012年   176篇
  2011年   189篇
  2010年   159篇
  2009年   75篇
  2008年   110篇
  2007年   85篇
  2006年   78篇
  2005年   55篇
  2004年   56篇
  2003年   45篇
  2002年   32篇
  2001年   15篇
  2000年   22篇
  1999年   16篇
  1998年   8篇
  1997年   6篇
  1996年   6篇
  1995年   1篇
  1994年   4篇
  1991年   1篇
  1983年   1篇
排序方式: 共有1858条查询结果,搜索用时 703 毫秒
101.
目前应用于油气田的示踪剂为水溶性示踪剂或者是气体示踪剂.经过多年的研究,开发了一种新类型的微颗粒固体示踪剂,并在长庆油田致密油藏中成功施工,标志着从实验成功走向了矿场.固体示踪剂在油气田开发中的应用前景广阔,尤其对致密油藏井间裂缝开度的定量描述具有指导意义.  相似文献   
102.
谭德凯  田利辉 《金融论坛》2021,26(2):8-17,46
本文基于动态条件相关混频数据抽样模型,研究人民币汇率收益率与国际原油收益率的相关性.结果表明:人民币收益率与国际原油收益率存在一定程度负相关关系,但负相关程度不高;中国原油进口量和制造业采购经理指数上升能提升人民币和原油收益率的负相关程度,面额效应的作用机制存在;国际期货市场投机活跃程度增强能提升人民币和原油收益率的负...  相似文献   
103.
方行明  何永芳 《改革》2007,(9):115-121
近年来,石油短缺、油价昂贵导致世界生物能源产业,如燃料乙醇产业迅猛扩张。而乙醇产量的迅猛增长,消耗了大量粮食类农产品(特别是玉米),从而造成全球性的"粮食能源化"问题。为应对能源危机和粮食危机的同时出现,我国应调整燃料乙醇的原料结构,采用非口粮类能源作物、庄稼废料、城市垃圾等,实现能源与粮食的双丰收,推动经济社会的可持续发展。  相似文献   
104.
We investigate the effect of energy commodity price movements on market and electricity index returns in Turkey for the periods before, during, and after the year 2008. Although the Turkish economy is highly reliant on oil, we find that oil price does not lead either electricity or market indexes. This might be attributable to sluggish integration of financial markets in Turkey compared to developed markets. Natural gas price leads electricity index in the pre-2008 period. Its significance is reduced following the decline in natural gas usage in electricity production. This suggests that commodity dependence may be driving the link between commodity and asset prices in related sectors.  相似文献   
105.
There are different academic assessments of the principal forces behind Russia’s GDP growth. Studies that reconstruct capital stocks using gross fixed capital formation and the perpetual inventory method find that total factor productivity growth has been paramount to GDP growth. On the other hand, capital services datasets that have recently been made available find that capital developments have been instrumental in driving economic growth. We reconstruct a capital stock series for Russia for 1995–2013 and compare the results to two capital services time series using the Solow growth model. We also take into account terms of trade developments that have lent strong support to Russia’s economy. The terms of trade is shown to have been an important factor behind the development of gross fixed capital formation and thus GDP growth.  相似文献   
106.
Oil palm plantations in Indonesia have been linked to substantial deforestation in the 1990s and 2000s, though recent studies suggest that new plantations are increasingly developed on non-forest land. Without nationwide data to establish recent baseline trends, the impact of commitments to eliminate deforestation from palm oil supply chains could therefore be overestimated. We examine the area and proportion of plantations replacing forests across Sumatra, Kalimantan, and Papua up to 2015, and map biophysically suitable areas for future deforestation-free expansion. We created new maps of oil palm plantations for the years 1995, 2000, 2005, 2010 and 2015, and examined land cover replaced in each period. Nationwide, oil palm plantation expansion occurred at an average rate of 450,000 ha yr−1, and resulted in an average of 117,000 ha yr−1 of deforestation, during 1995–2015. Our analysis of the most recent five-year period (2010–2015) shows that the rate of deforestation due to new plantations has remained relatively stable since 2005, despite large increases in the extent of plantations. As a result, the proportion of plantations replacing forests decreased from 54% during 1995–2000, to 18% during 2010–2015. In addition, we estimate there are 30.2 million hectares of non-forest land nationwide which meet biophysical suitability criteria for oil palm cultivation. Our findings suggest that recent zero-deforestation commitments may not have a large impact on deforestation in Sumatra, where plantations have increasingly expanded onto non-forest land over the past twenty years, and which hosts large potentially suitable areas for future deforestation-free expansion. On the other hand, these pledges could have more influence in Kalimantan, where oil palm driven deforestation increased over our study period, and in Papua, a new frontier of expansion with substantial remaining forest cover.  相似文献   
107.
By analysing the different roles of the Indonesian state in arranging finance schemes for palm-oil development since 1945, this article aims to answer two questions: What are these roles? And to what extent have they prioritised or balanced economic growth, social equity, and environmental protection? We conclude that the state has never been absent from the palm-oil industry but has had different and changing financing roles that are historically contingent and shaped by the evolving economic and political landscape. Furthermore, these roles reflect Indonesia’s priorities of achieving economic growth through palm-oil development, furthering social equity, and, recently, promoting environmental sustainability.  相似文献   
108.
利用气质联用仪对水蒸馏法提取鲜桑(Morusalba)叶与干桑叶的精油挥发性组分进行分析,二者均含有醇类化合物、酸类化合物、烃类化合物、酮类化合物和酯类化合物。鲜桑叶精油挥发性组分中第一主成分为植醇,干桑叶精油挥发性组分中第一主成分为棕榈酸。鲜桑叶精油中含有丁基化羟基甲苯和质量分数较高的植醇,具有开发为化妆品的潜在价值。  相似文献   
109.
This article brings new insights on the role played by (implied) volatility on the WTI crude oil price. An increase in the volatility subsequent to an increase in the oil price (i.e. inverse leverage effect) remains the dominant effect as it might reflect the fear of oil consumers to face rising oil prices. However, this effect is amplified by an increase in the oil price subsequent to an increase in the volatility (i.e. inverse feedback effect) with a two-day delayed effect. This lead-lag relation between the oil price and its volatility is central to any type of trading strategy based on futures and options on the OVX implied volatility index. It is of interest to traders, risk- and fund-managers.  相似文献   
110.
介绍了项目质量成本的概念及内涵,分析了质量和成本之间的辩证关系,总结了消减质量成本的7项措施,并提出了质量改进成本投入与收益平衡分析的建议。实践证明,通过增加预防与改进成本,可提高项目施工质量,有效降低鉴定成本和非一致性成本,最终降低项目总的质量成本,大幅度提高项目经济效益。  相似文献   
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