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61.
[目的]为了解叶尔羌河平原绿洲耕地利用变化与粮食产量的耦合关系,以此优化粮食生产系统的指导方式,提高叶尔羌河平原绿洲粮食产量,协调叶尔羌河平原绿洲耕地利用转型与粮食产量的耦合关系,并为叶尔羌河平原绿洲的粮食安全保护提供一定的政策启示。[方法]文章运用熵值法,以粮食生产相关的“投入”指标为评价依据,耕地利用强度由地均化肥使用强度、有效灌溉比例、复种指数及地均农业机械化水平等4个指标构成,以及利用1990—2016年叶尔羌河平原绿洲粮食产量,分析其耕地利用转型和粮食产量耦合关系时空变化。[结果](1)1990—2016年叶尔羌河平原绿洲各县耕地利用强度不断增大,并且区域时空格局差异明显,研究初期东北部地区的耕地利用程度强于西部地区,而2016年呈现出西南—中东部强,东北部弱的态势; 从粮食产量方面来看,叶尔羌河平原绿洲粮食产量整体有所增长,空间分异特征较不明显;(2)耕地利用强度—粮食产量耦合类型时空演化特征明显,高耦合值区增加,低耦合区值逐年减少; 从空间上看,叶尔羌河平原绿洲西部地区耕地利用转型与粮食产量耦合度越来越高。(3)耕地利用转型推动粮食生产格局不断演化,叶尔羌河平原绿洲耕地利用转型与粮食产量耦合度在1990—2016年呈现耦合度逐渐增加的趋势,耕地利用转型对保障区域粮食安全具有重要作用。[结论]叶尔羌河平原绿洲粮食产量随着耕地利用转型的不断深入而不断提高,耕地利用转型对粮食安全具有有利影响。  相似文献   
62.
This study investigates consumer engagement behaviors in the online wildlife trade, drawing implications for conservationists. The first study undertook a quantitative content analysis of 500 Facebook posts in wildlife trade lateral exchange markets to show how creative strategies, media type and persuasion tactics influence the number of likes and comments that posts receive. The second study then undertook a thematic discourse analysis to develop a rich understanding of the culture, beliefs and motivations that influence how consumers engage in the markets. Findings showed that an overwhelming majority of posts use a functional or informational strategy and that when posts use overt persuasion tactics the number of comments decrease. A conceptual model of how cultural factors may impact the success of marketing strategies is then proposed. These findings have implications for conservationists who seek to build engagement with wildlife trade consumers online.  相似文献   
63.
Previous research shows mixed findings about how cultural distance may affect bilateral trade. To reconcile the mixed findings, we examine how key moderators at both the country-pair level (product type) and the country level (uncertainty avoidance) affect the magnitude of the effect of cultural distance on bilateral trade. Using trade data on electronic products from 90 nations during 2008–2 014, we show that cultural distance in general has a negative impact on bilateral trade. However, the effect is more pronounced when the trade is on experience (versus search) products, or if the importing country is low (versus high) in uncertainty avoidance. Apart from its moderating effect, experience (versus search) product also has a negative main effect on bilateral trade, but its impact is stronger for countries low (versus high) in uncertainty avoidance.  相似文献   
64.
This article presents evidence concerning the pattern of New Zealand dairy exports duration and survival from 1989 to 2017. It also analyses the influence of a set of supply, demand and gravity‐type drivers on the hazard rate for New Zealand dairy export relationships. The findings are summarised as follows. First, New Zealand dairy export relationships are dynamic with numerous entries and exits to and from foreign markets. Around half of the relationships survived for only 1–2 years at the sequence level. Second, duration of sequence, left‐censoring, initial export, decomposed sequences, New Zealand export price index, the number of cows available for dairy production, the number of origins and destinations, and destination partner’s GDP are the most significant factors reducing the hazard rate of export relationships. As regards the effects of the non‐tariff measures, it is interesting that technical barriers of trade are found to significantly decrease the hazard rate. Only pre‐shipment inspection and contingent trade protective measures are significant impediments to New Zealand dairy export relationships. Finally, hazard probabilities for New Zealand dairy export relationships are estimated to be ‘L‐shaped’ over time, whether or not non‐tariff measures are applied to New Zealand dairy products.  相似文献   
65.
The importance of free trade agreements (FTAs) has been increasing as such agreements help reduce barriers to trade. This paper estimates the agricultural trade creation and export diversion effects of Australia’s free trade agreements (FTAs) at the aggregate and disaggregate levels, using the Poisson pseudo‐maximum‐likelihood (PPML) estimator. It includes 24 of Australia’s major trading partner countries comprising FTA and non‐FTA members and covers 22 years from 1996 to 2017. The heteroscedasticity robust regression error specification test (RESET) confirms the relevance of PPML over the Ordinary Least Square (OLS) estimator. Results showed that China–Australia, Korea–Australia, Australia–USA and Japan–Australia have larger trade creation effects in the agricultural sector. At the commodity level, variation in trade creation effects is estimated from the different trade agreements. Among the selected commodities, the larger effects were generated in trade in sugar and wine by the implementation of the majority of the trade agreements. Overall, the trade creation was greater than the export diversion of the FTAs. The findings of the study have implications for Australia’s future trade agreements.  相似文献   
66.
This article examines the expansion of the soybean complex in South America and the role of Chinese firms in expanding their presence in different sectors of the oilseed complex. The growth in trade relations between the two parties has been built on the export of primary commodities from South America and the import of Chinese manufactures—a trade pattern that reproduces core‐periphery dynamics identified by dependency theory scholars. Of particular importance in this bilateral trade is soybean, a crop that has been consolidated as the main export for several South American countries, fuelled by growing demand from China. This article explores China's role in the global political economy as a key agri‐business player and the implications for new relations of dependency by studying the strategies deployed by Chinese firms to increase their influence in the governance of the soybean nexus.  相似文献   
67.
《中国林业经济》2020,(2):51-53,88
发达国家以保护全球环境为名提出了有关碳关税的政策,但是结合碳关税的相关政策内容来看,其动机是为了抑制发展中国家高能耗产品的出口,以便保证自身高能耗产品在国际的地位。我国身为纸制品出口贸易大国,一旦实行碳关税政策,将会对经济发展带来严重影响,基于此本文分析碳关税对中国纸制品出口贸易的长期影响效应具有十分重要的意义。  相似文献   
68.
Economic institutions are linked to economic growth because they create conditions favourable for production and exchange. Institutions can give a country comparative advantage in producing some goods. If its trading partners lack such institutions, it can still enjoy their benefits by importing these goods. Some institutions, such as intellectual property rights, have non‐excludable benefits because the resulting production is intangible, non‐rival, and often publicly disclosed. The profits, or surplus, that result, however, is rival. Foreign countries can ‘free ride’ on this benefit by misappropriating rival surplus through infringement. This article develops a theory of institutional free riding in which firms in one country free ride on the benefit of foreign institutions to the detriment of their competitor firms and their countries' institutions. It evaluates the incentives of firms and governments for this free riding, its effects, and potential responses to mitigate these effects.  相似文献   
69.
Given that the United States is an engine of global stock market while China is the largest emerging market with a cornucopia of anomalies in particular, it is vital to investigate the risk-return relationship in the two markets. This paper brings new insights not only into risk-return tradeoff, but also to the leverage effect, with the application of the fractionally co-integrated vector auto-regression (FCVAR) model capturing the fractional cointegrated relationship and long memory property. Results show that China stock markets own the property of double long memory but the US markets don’t. Most of all, in the US market, a positive risk-return tradeoff exists for the whole sample while after the crisis, even we find the negative relation, it’s not a volatility feedback effect but low risk and high returns. However, there is only a volatility feedback effect in China stock markets. Besides, there is a leverage effect in the US market, while Chinese market exhibits a reverse one, another anomaly, indicating significant difference in the two markets again.  相似文献   
70.
Trade is an integral part of the Canadian economy. The main institutional drivers governing trade are bilateral and multilateral agreements outlining permissible trade distorting measures. Since its inception in 1972, Canada's supply management system has remained protected throughout trade negotiations. The system appears, by any economic measure, to be having an increasingly disproportional influence in recent trade negotiations. However, trade agreements serve not only to maximize social surplus, but also to maximize some measure of political welfare. Canada has recently negotiated three prominent trade agreements: the Canada-European Union Comprehensive Economic and Trade Agreement (CETA) came into effect in the latter part of 2017; the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP) came into effect at the end of 2018; and the Canada-United States-Mexico Agreement (CUSMA) could come into effect in 2020. Collectively, these agreements have guaranteed increased market access for fresh and processed dairy products. We build a spatial partial equilibrium model of the Canadian dairy industry consisting of three regions and 10 commodities to assess the individual and cumulative effect of these trade agreements. We pay particular attention to the institutional drivers within today's dairy sector: milk protein isolates; component pricing, including Class 7; and differential demand growth. We find that the aggregate impacts are: (a) a 1.4% decrease in the marginal retail price; (b) a 4.8% decrease in the blended producer price; and (c) an overall increase in social welfare of 7.8%. Worth noting, the decrease in producer surplus varies from 0.7% in the western region to 1.5% in Ontario. Our results may be relevant to future negotiations as well as the publicly promised compensation package for dairy producers.  相似文献   
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