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   12056篇
  免费   319篇
  国内免费   29篇
财政金融   2018篇
工业经济   698篇
计划管理   1653篇
经济学   2093篇
综合类   323篇
运输经济   66篇
旅游经济   173篇
贸易经济   1468篇
农业经济   434篇
经济概况   1359篇
水利工程   2113篇
邮电经济   6篇
  2022年   94篇
  2021年   134篇
  2020年   137篇
  2019年   187篇
  2018年   223篇
  2017年   248篇
  2016年   213篇
  2015年   196篇
  2014年   242篇
  2013年   1135篇
  2012年   442篇
  2011年   502篇
  2010年   406篇
  2009年   371篇
  2008年   440篇
  2007年   424篇
  2006年   432篇
  2005年   391篇
  2004年   305篇
  2003年   214篇
  2002年   243篇
  2001年   217篇
  2000年   189篇
  1999年   171篇
  1998年   175篇
  1997年   176篇
  1996年   168篇
  1995年   131篇
  1994年   141篇
  1993年   159篇
  1992年   177篇
  1991年   182篇
  1990年   130篇
  1989年   141篇
  1988年   111篇
  1987年   132篇
  1986年   137篇
  1985年   170篇
  1984年   153篇
  1983年   179篇
  1982年   154篇
  1981年   151篇
  1980年   167篇
  1979年   145篇
  1978年   118篇
  1977年   133篇
  1976年   125篇
  1975年   125篇
  1974年   118篇
  1973年   96篇
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
71.
Human capital raises rural incomes, but this effect is swamped by higher returns to human capital in urban markets. This leads to "brain drain" from rural areas. Populations grow more rapidly in rural counties that have a diversified employment base. Farm population grows faster (or declines more slowly) in counties with relatively high farm income, and nonfarm populations grow faster in counties with relatively high nonfarm income. However, higher farm incomes lead to slower nonfarm population growth and vice versa. Rural county government services financed by local taxes or debt have neutral or negative effects on population growth.  相似文献   
72.
Beef cattle producers were surveyed in Texas and Nebraska to investigate perceptions of sources of risk, the effectiveness of risk management strategies, and interest in further risk management education, particularly production risk, using probit analysis. Important decision variables identified are age, prior use of risk management tools, previous attendances of risk management education, and risk aversion. Severe drought and cattle price variability are identified as primary risk factors with potential to affect farm income. Extremely cold weather and disease are of less importance. Understocking pasture and storing hay are perceived most effective as risk management options.  相似文献   
73.
We examine the impact of initial public offerings (IPOs) on rival firms and find that the valuation effects are insignificant. This insignificant reaction can be explained by offsetting information and competitive effects. Significant positive information effects are associated with IPOs in regulated industries and the first IPO in an industry following a period of dormancy. Significant negative competitive effects are associated with larger IPOs in competitive industries, those in relatively risky industries, those in high‐performing industries, and those in the technology sector. IPO firms that use the proceeds for debt repayment appear to represent a more significant competitive threat to rival firms relative to IPO firms that use their proceeds for other purposes.  相似文献   
74.
Managerial Equity Ownership and the Demand for Outside Directors   总被引:1,自引:0,他引:1  
This paper examines the linkage between the use of outside directors and managerial ownership. We conjecture there are two linkages: the standard incentive‐alignment demand for monitoring when managers own little stock and an entrenchment‐amelioration demand when managerial stock ownership is high. As a consequence, we predict the association between managerial ownership and board composition will be nonlinear (U‐shaped if the entrenchment effect is sufficiently pronounced). Using UK data, we find that both quadratic and logarithmic models outperform the simple linear relationship assumed in prior research and that the substitution between managerial ownership and board composition is stronger than hitherto supposed.  相似文献   
75.
76.
77.
Post-treatment of an UASB reactor effluent, fed with domestic sewage, was conducted using two-stage flotation and UV disinfection. Results were compared to those obtained in a parallel stabilisation pond. The first flotation stage employed 5 - 7.5 mg L(-1) cationic flocculant to separate off more than 99% of the suspended solids. Then, phosphate ions were completely recovered using carrier flotation with 5-25 mg L(-1) of Fe (FeCl3) at pH 6.3-7.0. This staged flotation led to high recoveries of water and allowed us to separate organic matter and phosphate bearing sludge. The water still contained about 1 x 10(2) NMP/100 mL total coliforms, which were removed using UV radiation to below detection levels. Final water turbidity was < 1.0 NTU, COD < 20 mg L(-1) O2 and 71 mNm(-1), the liquid/air interfacial tension. This flotation-UV flowsheet was found to be more efficient than the treatment in the stabilisation pond and appears to have some potential for water reuse. Results were discussed in terms of the biological, chemical and physicochemical mechanisms involved.  相似文献   
78.
79.
Given self-protection from an undesirable environmental externality, we examine, under several conditions, the efficiency properties of cooperative and noncooperative behavior. We demonstrate that if self-protection can transfer the externality to another agent, then noncooperative behavior will lead to overprotection. If self-protection filters or dilutes the externality, then noncooperation leads to underprotection. In addition, overprotection will worsen if an agent with more relative power is allowed a first-mover advantage or if the damage function is elastic and transferability is uncertain. Finally, a reduction in uncertainty about transferability will accentuate overprotection if the damage function is inelastic. Our results suggest that coordination of protection activities among agents will enhance the overall gains from environmental policy in the European Single Internal Market of 1992. Coordination minimizes the costs of environmental protection, thereby reducing the public credibility of its foes.  相似文献   
80.
We study the optimal monetary policy in a two-country open-economy model under two monetary arrangements: (a) multiple currencies controlled by independent policy makers; (b) common currencies with a centralized policy maker.
Our findings suggest that: (i) monetary policy competition leads to higher long-term inflation and interest rates with large welfare losses; (ii) the inflation bias and the consequent losses are larger when countries are unable to commit to future policies; (iii) the welfare losses from higher long-term inflation dominates the welfare costs of losing the ability to react optimally to shocks.  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