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101.
[目的]为清晰识别影响农户生态耕种行为的主要因素,以期为加强耕地生态保护、保障农作物质量安全、提升农户耕种收益、实现农业现代化目标提供参考。[方法]基于江西省11市47县(区)1488份农户微观调查数据,在分析农户生态耕种特征基础上,运用二元Logistic和Probit模型对农户生态耕种行为影响因素开展实证研究。[结果]农户生态耕种10种具体行为的采纳情况差异明显,其中施用有机肥采纳程度最高,生态农业模式采纳程度最低。农户采纳生态耕种整体水平不高,但仍具备进一步推广的潜力。家庭劳动力比重、生态耕种成本认知、新型农业经营主体、法律法规认知、生态耕种收益认知、生计分化和生态环境认知等解释变量是影响农户生态耕种行为的主要内部因素,政府补贴、农田基础设施、生产交流程度、耕地质量变化和生态耕种信息获取难度等则是主要的外部影响因素。[结论]政府及基层管理部门应在推动农户非农就业生计、大力培育新型农业经营主体、加强生态耕种宣传与推广、完善政策扶持与管控机制等方面制定针对性的政策措施。 相似文献
102.
绿地有一定的雨洪调蓄功能,雨洪状况下,如何在汇水系统尺度利用和保护绿地亟待研究。选取95处位于武汉港西汇水系统的地块,调研地块性质,利用ArcGIS提取不透水比例及平均坡度,并进行SWMM水文模型演算。通过实验性模拟结果的对比,得出汇水系统的绿地雨洪调蓄效率(λ=0.13m3/m2)、汇水系统(g=36%)和各类用地(g=18%~47%)基于雨水调蓄理念下的最低绿地率,使汇水系统水文状况达到海绵城市建设标准。讨论了不同重现期下汇水系统的绿地雨洪调蓄效能,旨在完善绿地雨洪调蓄的研究方法、指标体系及利用与保护策略,为相关研究与实践提供借鉴。 相似文献
103.
邓雯婧 《国土资源科技管理》2020,(2):116-124
农用地估价,是以农用地定级为基础的农用地基准地价评估。农用地定级与基准地价评估是根据农用地的自然属性和经济属性,对农用地的质量优劣进行综合评定,划分土地质量级别并测算土地价格。以广东云城区国有农业用地为研究对象,采取"先定级后估价"的方式,通过因素因子法综合评定农用地级别,再通过样点地价法进行估价,确定了农用地的基准地价。 相似文献
104.
Improving children's access to primary and secondary education is a strategic goal for many global development agencies and government policymakers. Nevertheless, there is relatively little research examining how changes in rural school supply affect future labor markets. We leverage variation in the timing and location of secondary school construction in Southern Mexico to identify the effects of school supply on labor outcomes. We find that school construction increases expected education for school-aged children by about 4 years and raises the share of years working in the nonagricultural sector between the ages of 18–22 by 29.8 percentage points. The magnitude of the effects on share of years doing nonagricultural work is smaller for individuals from homes where an indigenous language is spoken. Our findings indicate that rural school construction in less-developed countries can accelerate the transformation from agricultural to nonagricultural economies, but there may be heterogeneous effects across socioeconomic groups and ethnicities. 相似文献
105.
In this paper, we introduce a functional method to investigate how betas change over time in factor models. Based on the China A-share data, we drop the constant beta assumption in the CAPM and multi-factor models to estimate the time-varying betas directly from the functional data regression. The empirical results show that exposures to all risk factors have certain time-varying patterns in the Chinese A-share stock market. 相似文献
106.
随着我国建筑行业的不断发展,为了迎合节能、环保需求,绿色建筑开始出现。对于绿色建筑来说,要想体现出环保意识,需要在建筑中添加可再生能源,这样不仅符合当前我国绿色发展的理念,还能减少对环境的污染,可以更好地保护环境。论文针对可再生能源技术在绿色建筑中的应用展开分析。 相似文献
107.
Mahsa Jahan Dideh 《Economics of Transition》2020,28(2):265-313
This paper investigates the effect of trade liberalization on the provision of public goods and shows that inequality also plays a vital role here. Public goods help enhance the productivity of firms, lower prices and raise profitability. The provision of public goods has different effects in closed and open economies. In an open economy, the impact of productive spending on increasing profit is stronger. Consequently, the opening up of the economy shifts the benefits of productive public goods from consumers to firms. As the median voters’, share of the firm’s profit rises, public goods become more appealing and flourish. Consequently, the manufacturing export is boosted by a rise in productivity. 相似文献
108.
We examine the relationship between environmental regulation and spatial development in China. Exploiting changes in national pollution standards for three industries, ammonia, paper and cement, we measure the impact of environmental regulation on industry productivity. Our results suggest that national pollution standards do not affect industry productivity, but they reallocate productivity spatially. We show that regulated industries located in developing cities increase their productivity compared to similar industries in other cities. This means that environmental regulation affects the spatial distribution of technology in China and might influence long‐term spatial development by reducing geographical disparities. 相似文献
109.
The rise of the Household Responsibility System has been widely viewed as a significant contribution to China's agricultural growth. However, this empirical conclusion is rested upon a convenient but doubtful presumption that the process of institutional change, also known as decollectivization, is exogenous. We contribute to this literature by explicitly recognizing the endogeneity of institutional changes, and exploit exogenous variations in lagged weather shocks and initial fixed assets for consistent estimation. With improved data on irrigation, mechanization, weather and institutional changes in a provincial panel data during 1970–1987, the results of panel instrumental estimations reveal that the Household Responsibility System had a significantly positive effect on China's agricultural growth, which was larger than indicated by OLS estimates that suffer from adverse selection and attenuation biases. 相似文献
110.
"省直管县"改革一改以往"省-市-县"的管理模式,有助于提高县级政府的财政分权水平。为缓解内生性,将"省直管县"改革视为一项准自然实验,构建双重差分模型检验了财政分权对全要素生产率的因果效应。研究发现:①财政分权对全要素生产率的正向促进作用高于负面阻碍作用,但不同形式的分权影响有异质性,具体来说财权的下放有利于全要素生产率的提高,经济社会事务管理权限的下放则不利于。②当地方政府自主权提高时,其"重生产、轻服务"的支出偏好,使得当地基础设施供给增加,而能够增强地方软实力、加快创新要素集聚的公共服务供给相应减少,造成了全要素生产率的损失,导致在经济高质量高效益增长中政府"有形之手"的作用发挥不够。③随着改革的推进,财政分权对全要素生产率的正向作用逐渐减弱,并不再显著。据此,从合理划分省以下政府的事权与支出责任,充实基层政府财力;提高公共服务类指标在政府官员政绩考核中的权重,加强各县(市)政府间的合作,实现各自为政的地方经济向统一市场整合等方面提出政策建议。 相似文献