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1.
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   
2.
The prospect for electric vehicles as a climate change solution hinges on their ability to reduce gasoline consumption. But this depends on how many miles electric vehicles are driven and on how many miles would have otherwise been driven in gasoline-powered vehicles. Using newly-available U.S. nationally representative data, this paper finds that electric vehicles are driven considerably fewer miles per year on average than gasoline-powered vehicles. The difference is highly statistically significant and holds for both all-electric and plug-in hybrid vehicles, for both single- and multiple-vehicle households, and both inside and outside California. The paper discusses potential explanations and policy implications. Overall, the evidence suggests that today’s electric vehicles imply smaller environmental benefits than previously believed.  相似文献   
3.
The American Psychological Association Task Force recommended that researchers always report and interpret effect sizes for quantitative data. However, no such recommendation was made for qualitative data. Thus, the first objective of the present paper is to provide a rationale for reporting and interpreting effect sizes in qualitative research. Arguments are presented that effect sizes enhance the process of verstehen/hermeneutics advocated by interpretive researchers. The second objective of this paper is to provide a typology of effect sizes in qualitative research. Examples are given illustrating various applications of effect sizes. For instance, when conducting typological analyses, qualitative analysts only identify emergent themes; yet, these themes can be quantitized to ascertain the hierarchical structure of emergent themes. The final objective is to illustrate how inferential statistics can be utilized in qualitative data analyses. This can be accomplished by treating words arising from individuals, or observations emerging from a particular setting, as sample units of data that represent the total number of words/observations existing from that sample member/context. Heuristic examples are provided to demonstrate how inferential statistics can be used to provide more complex levels of verstehen than is presently undertaken in qualitative research.  相似文献   
4.
公司业绩与财务杠杆   总被引:4,自引:0,他引:4  
柳松 《华东经济管理》2003,17(1):139-142
本文从实证角度分析了我国上市公司的财务杠杆对公司业绩的影响。结果表明,往年财务杠杆和当年财务杠杆对当年公司业绩的影响截然相反。财务杠杆对公司的息税后收益和息税前收益均有影响。长期负债率和长期借款率对公司业绩的影响分别比同年的流动负债率和短期借款率对公司业  相似文献   
5.
探讨了葡萄球菌肠毒素B(SEB)对动物移植性肿瘤的抑制作用。以小鼠移植性肿瘤肝癌(Heps)、L2网织细胞瘤和肉瘤180(S180)为模型,环磷酰胺为阳性对照组,生理盐水为阴性对照组,观察不同剂量(5、10和20ng·Kg-1·d-1)SEB的抗肿瘤作用。不同剂量的SEB对小鼠肝癌(Heps)有明显抑制作用,抑瘤率分别为44.6%、46.7%和51.8%(P值均<0.05),对小鼠L2网织细胞瘤也有一定的抑制作用,抑瘤率分别为17.4%、44.7%(P<0.05)和44.1%(P<0.05)。SEB对小鼠S180的抑制作用不显著。结论是葡萄球菌肠毒素B(SEB)具有抗肿瘤效应,可作为一种有前途的抗肿瘤制剂进行研究。  相似文献   
6.
服务业集聚与产业结构优化关系探究   总被引:3,自引:0,他引:3  
随着全球化进程的不断加快,服务业集聚已经成为人们普遍关注的话题。产业集聚在获得规模效应的同时避免了垄断现象的产生,服务业集聚不但拥有这样的优势,而且还有自己独特的形成和发展特点。从产业结构的优化角度切入,借助区位商和专门化率等分析指标,以江苏省和上海市为例,对服务业集聚的形成进行理论和实证分析,提出产业结构的优化对于服务业集聚的形成和发展有着积极的作用。合理的产业结构能够为服务业集聚提供坚实的基础,各地区应该根据各自的产业特点积极的进行优化,催生服务业集聚,加快本地区经济的进一步发展。  相似文献   
7.
在香港发行人民币债券,既是香港特区政府多年来的愿望,也是人民币国际化的重要一步,因此具有极其重要的意义。本文通过在香港发行人民币债券对内地和香港的积极作用和消极作用的分析,提出了在港发行人民币债券应注意的问题以及相关对策建议。  相似文献   
8.
Do incentives differ between large and small organizations? Results from a representative survey of compensation managers are used to shed light on the issues. I find that (i) small establishments rely less on pecuniary incentives, and have a significantly more hostile attitude towards incentive schemes based on competition and relative rewards; (ii) large units are more vulnerable to mechanisms of efficiency wages, effects that remain even after controlling for differences in monitoring ability; (iii) large units are more prone to indicate that negative reciprocity is important, and that their employees care about relative pay. I argue that these findings fit with behavioral stories of incentives and motivation, in particular those stressing group interaction effects, inequity aversion and gift exchange.  相似文献   
9.
跨海通道与日本经济   总被引:2,自引:0,他引:2  
日本由于岛国的独特地理特征,为了促进其经济和社会的发展,在二战之后进行了大规模的跨海桥梁以及海底隧道建设,从而实现了四大主岛陆路交通的联结。日本一系列跨海通道的建设,对促进其经济腾飞、实现地区均衡发展,起到了积极的推动作用。这对我国当前的五大跨海交通工程,具有重要的启示和借鉴。  相似文献   
10.
We examine the presence or absence of asymmetric volatility in the exchange rates of Australian dollar (AUD), Euro (EUR), British pound (GBP) and Japanese yen (JPY), all against US dollar. Our investigation is based on a variant of the heterogeneous autoregressive realized volatility model, using daily realized variance and return series from 1996 to 2004. We find that a depreciation against USD leads to significantly greater volatility than an appreciation for AUD and GBP, whereas the opposite is true for JPY. Relative to volatility on days following a positive one-standard-deviation return, volatility on days following a negative one-standard-deviation return is higher by 6.6% for AUD, 6.1% for GBP, and 21.2% for JPY. The realized volatility of EUR appears to be symmetric. These results are robust to the removal of jump component from realized volatility and the sub-samplings defined by structural-changes. The asymmetry in AUD, GBP and JPY appears to be embedded in the continuous component of realized volatility rather than the jump component.  相似文献   
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