全文获取类型
收费全文 | 4610篇 |
免费 | 220篇 |
国内免费 | 48篇 |
专业分类
财政金融 | 185篇 |
工业经济 | 473篇 |
计划管理 | 1211篇 |
经济学 | 957篇 |
综合类 | 385篇 |
运输经济 | 405篇 |
旅游经济 | 63篇 |
贸易经济 | 417篇 |
农业经济 | 236篇 |
经济概况 | 546篇 |
出版年
2024年 | 20篇 |
2023年 | 79篇 |
2022年 | 83篇 |
2021年 | 138篇 |
2020年 | 117篇 |
2019年 | 100篇 |
2018年 | 87篇 |
2017年 | 147篇 |
2016年 | 152篇 |
2015年 | 192篇 |
2014年 | 424篇 |
2013年 | 359篇 |
2012年 | 490篇 |
2011年 | 605篇 |
2010年 | 433篇 |
2009年 | 304篇 |
2008年 | 304篇 |
2007年 | 199篇 |
2006年 | 174篇 |
2005年 | 113篇 |
2004年 | 82篇 |
2003年 | 78篇 |
2002年 | 31篇 |
2001年 | 24篇 |
2000年 | 33篇 |
1999年 | 23篇 |
1998年 | 14篇 |
1997年 | 13篇 |
1996年 | 10篇 |
1995年 | 10篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 8篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1987年 | 1篇 |
1985年 | 3篇 |
1984年 | 7篇 |
1983年 | 1篇 |
1982年 | 6篇 |
1979年 | 1篇 |
排序方式: 共有4878条查询结果,搜索用时 15 毫秒
1.
High firewood consumption for heating produces high levels of pollution in cities in central and southern Chile, with serious consequences for health and quality of life. Energy efficiency measures (EEMs) have been identified as the best strategy to reduce air pollution and maximize social benefits. However, their adoption has been slow. The objective of this article is to investigate household preferences for financial incentives needed to promote private investments in EEMs in Central-Southern Chilean households and study the role of energy savings and the uncertainty about potential savings in the investment decision, with the aim of finding solutions to increase the adoption of these technologies. We use a choice experiment to explore the trade-off between the investment costs, financial instruments, energy savings, and the uncertainty about achieving the theoretical savings provided by engineering and architectural models. The results show that financial instruments play the most important role in this decision, followed by the savings achieved by the retrofit. Householders prefer to finance their investments with a mix of their personal resources and medium-term credits, trying to avoid long-term commitments. Although uncertainty was found to be a significant variable, it seems to play a small role in the investment decision. 相似文献
2.
Christopher Ambrey Matthew Bitzios 《International Journal of Sustainable Transportation》2018,12(10):737-752
This study investigates the correlates of a resident's walking behaviors and aims to shed light on mechanisms through which walking may be encouraged. The results of this investigation paint a complex and nuanced picture of the residents’ walking behaviors in South East Queensland, Australia. The results suggest that sociodemographic characteristics separately may contribute greatly to whether or not one engages in walking behaviors. Further, cumulatively these differences might be greater for some groups of residents compared to others. One of the most prominent findings of the study is that the purpose, the characteristics of the origin, and the characteristics of the destination of a trip tended to be similar in the heterogeneity they exhibit over the distribution of time spent walking. For example, pick something up, undertake work, or engage in personal business, move to or from a workplace, shop, or social place are activities that tend to be associated with walking as a main mode of transport and a higher number of walking episodes. However, these trips tended to be short. 相似文献
3.
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
4.
以中国2013年以来实行的碳排放交易试点政策作为准自然实验事件,基于2000-2017年中国30个省市的面板数据,运用双重差分法实证检验碳排放交易制度的节能减排效应及影响机制。研究发现,碳排放交易制度有利于实现中国经济“节能”与“减排”的双重目标,并通过了一系列稳健性检验;作用机制检验表明,能源效率提升和能源结构转型都是碳排放交易制度实现节能减排目标的重要路径;能源效率提升在碳排放交易制度实现“节能”和“减排”中分别发挥了10.19%和5.93%的作用,而能源结构转型分别发挥了48.87%和52.95%的作用。这意味着中国碳排放交易制度实现节能减排的主要动力来自能源结构转型,而非能源效率提升。能源结构转型涉及问题更加宏观和深层,这为中国加快推进节能减排进程,特别是完成2030年碳达峰和2060年碳中和的国际承诺提供政策启示。 相似文献
5.
This study investigates the importance of mindfulness‐based organization systems and policies on the organization's continuous efforts to become a greener company. The study is devised as a pooled cross‐sectional time series analysis of productivity in energy consumption, water utilization, and waste generation and recycling of U.S. companies. The data set taken from U.S. Newsweek 500 recorded 600 companies dispersed into 63 industries during the period of 2012–2014 and provided 1,498 company–industry–year observations. The study found that systems and policies (e.g., deployment of third‐party auditors for its environmental metrics report; linkage of the remuneration of company's senior executive team with the achievement of environmental performance targets; and establishment of a committee at the Board of Directors' level whose mandate includes sustainability of the company in environment‐ and resource‐related matters) connect the company's mindfulness to its effort in improving the environmental quality through the company's productivity in energy consumption, water utilization, and waste generation and recycling. The relationships are positive and significant. Also, systems and policies serve as a motivator for the firm to continue to improve upon the current achievements. The study emphasizes the importance of translating organizational and individual mindfulness into organization policies and systems in order to motivate the organization to continuously improve its productivity in energy consumption, water utilization, and waste generation and recycling leading to improvements in environmental quality. 相似文献
6.
Christoffel Venter Gail Jennings Darío Hidalgo Andrés Felipe Valderrama Pineda 《International Journal of Sustainable Transportation》2018,12(2):140-152
The paper offers an analysis of empirical evidence on the equity impacts of operational Bus Rapid Transit (BRT) systems in the Global South. The focus is on vertical equity, i.e. whether BRT systems achieve progressive benefits for poorer segments of the population. Findings from Africa, Asia, and Latin America all suggest that BRT does offer significant benefits to low-income groups, in terms of travel time and cost savings, access enhancement, and safety and health benefits. However benefits are often skewed toward medium-income users and thus less progressive than they might be. Two primary reasons for this are insufficient spatial coverage and inappropriate fare policies. While many features of BRT potentially allow it to deliver pro-poor outcomes, such outcomes only materialize if BRT implementers pay specific and sustained attention to equity. The paper identifies key issues that need to be addressed to steer BRT implementation toward more socially sustainable outcomes—including better integration with other transit, paratransit, and nonmotorized transport services, and with the housing sector. 相似文献
7.
The introduction of traffic management schemes has been one response of the National Parks to the problem of ever-increasing car-borne visitors and the consequent damage caused to the rural environment. By reviewing these schemes and by determining and explaining attitudes towards one particular traffic management experiment, the paper aims to deduce lessons for future policy. The analysis, based on two visitor surveys, suggests that the likelihood of success is improved when schemes are integrated, containing both ‘carrot’ and ‘stick’ elements. Since public perceptions are also found to be pivotal to its success, appropriate marketing of a scheme is vital. The paper concludes, however, that to achieve the fundamental objective of greater accessibility with less mobility, a more wide-ranging marketing effort is required intended to engender a sea change in attitude towards both the car and public transport. 相似文献
8.
精馏过程的节能,对于减少能源消耗,降低生产成本和保护环境具有十分重要的意义.在精馏过程中可以采用最适宜回流比操作和最佳进料状态,使用中间冷凝器和中间再沸器,高效精馏、热泵精馏.合理安排多组分物料分离流程,直接利用过程热量及开发应用高效换热器等措施.本文从最佳回流比R的选择、进料温度及进料状态的确定等方面,详细的分析了在精馏塔的设计过程中,如何实现设计的优化问题,以实现节能降耗. 相似文献
9.
发展中枢辐射铁路物流的探讨 总被引:1,自引:0,他引:1
传统的铁路物流组织模式有其局限性,已难以满足市场对快速运输的需求,铁路企业的改革势在必行。在阐述中枢辐射铁路物流表现形式的基础上,分析铁路企业发展中枢辐射铁路物流的必要性和可行性及所面临的困难,同时就铁路企业如何发展中枢辐射铁路物流提出了建设性意见。 相似文献
10.
近年来,铁路短途城际客运得到了很大的发展,开行城际列车已成为铁路运输企业新的经济增长点。新财务清算政策实施后,开行城际列车的效益受到一定程度的影响,针对存在的问题,就如何提高其效益水平进行了讨论。提出了完善开行结构、增加营业收入、减少客运付费、降低成本支出等建议措施。 相似文献