全文获取类型
收费全文 | 6650篇 |
免费 | 283篇 |
国内免费 | 62篇 |
专业分类
财政金融 | 433篇 |
工业经济 | 312篇 |
计划管理 | 1193篇 |
经济学 | 805篇 |
综合类 | 855篇 |
运输经济 | 49篇 |
旅游经济 | 141篇 |
贸易经济 | 1300篇 |
农业经济 | 1144篇 |
经济概况 | 763篇 |
出版年
2024年 | 13篇 |
2023年 | 84篇 |
2022年 | 125篇 |
2021年 | 246篇 |
2020年 | 241篇 |
2019年 | 174篇 |
2018年 | 143篇 |
2017年 | 233篇 |
2016年 | 221篇 |
2015年 | 199篇 |
2014年 | 465篇 |
2013年 | 644篇 |
2012年 | 541篇 |
2011年 | 690篇 |
2010年 | 488篇 |
2009年 | 439篇 |
2008年 | 459篇 |
2007年 | 357篇 |
2006年 | 327篇 |
2005年 | 262篇 |
2004年 | 171篇 |
2003年 | 132篇 |
2002年 | 96篇 |
2001年 | 80篇 |
2000年 | 53篇 |
1999年 | 26篇 |
1998年 | 19篇 |
1997年 | 14篇 |
1996年 | 11篇 |
1995年 | 10篇 |
1994年 | 5篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 8篇 |
1983年 | 9篇 |
1982年 | 1篇 |
排序方式: 共有6995条查询结果,搜索用时 31 毫秒
11.
Gabriella Phiri Peter Mumba Agnes Mangwera 《International Journal of Consumer Studies》2006,30(6):527-532
A survey was conducted in Lilongwe city urban markets in Malawi, to assess the quality of cooking oil used for frying potato chips. Purposive sampling was performed to come up with respondents who were using vegetable oils. A stratified random sampling was used to select the 32 informal food processors who were interviewed using a structured questionnaire. Oil samples were collected from the most commonly used brand of oil. Fifteen respondents were selected and these were divided into three categories of five: those who were not reusing the oil, those who were reusing the oil and those who were preparing potato chips and chicken in the same oil, for chemical analysis. The preliminary results showed that while the majority (59.4%) of the informal food processors discarded the oil after 1 day, 3.1% discarded it after 4 days and another 12.5% after 3 days. A larger proportion of the respondents (40.6%) used the leftover oils at home, 37.5% kept it in oil bottles, 3.1% kept it in plastic papers for reuse the following day. Also, most respondents (57%) indicated dark colour as the sign of oil deterioration, 29% discarded the oil after noticing foam formation while 8.2% and 6.1% said they discarded the oil after noticing a bad smell and food absorbing the oils respectively. A physical observation of the various oils showed that for most of the respondents (34%), the oils were dark brown in colour, in 22%, the oils were slightly dark brown and 16%, the oils were brown. Foam formation was noticed in 13% of the respondents. It was also noted that 91% of the respondents had not been trained or briefed of food quality and safety issues. A chemical analysis of the oils showed high values of free fatty acids (range, 0.84–1.4112 compared with 0.42 in the fresh oil) and peroxide values (range 14.7–16.6 compared with 9.0 in the fresh oil). It may be concluded that the oils being used by the informal food processors in Malawi are of poor quality and so the foods cooked in them may be a health hazard to the consumers and the processors themselves. Although this work in ongoing, it may be recommended at the outset that the health department of the city assemblies should inspect these oils for the good health of the consumers. 相似文献
12.
Reform of agricultural policies, notably the continuing elimination of production‐enhancing subsidies, makes it possible for policies to respond to social issues such as the rural environment and health in future. In this paper, we draw on a Rural Economy and Land Use (RELU) research project which is examining the potential for the development of healthy food chains and the implications for human health and the environment. One of the key issues to be addressed is consumers’ willingness to pay for the nutritionally enhanced food products from these new chains, but it is evident that only a partial understanding can be gained from a traditional economics approach. In the paper, we discuss how economists are beginning to incorporate views from other disciplines into their models of consumer choice. 相似文献
13.
Denial of Service (DoS) attacks consist of overwhelming a server, a network or a Web site in order to paralyze its normal activity. The additional parameter in Distributed Denial of Service (DdoS) attacks is the distributing strategy. It means that DDoS attacks do not come from a single computer but stem from all accessible channels and servers. Consequences are multiple, ranging from system errors, temporary inability to access the Web site for normal users to challenging the actual reliability of the Internet. Despite this, Internet users show carelessness. The explanation lies in the specificities of DDoS attacks. We explore possibilities to raise users' awareness about the actual amplitude of problems caused by DDoS attacks. We suggest a careful examination of Internet pricing mechanisms and switching from flat to usage-constraining pricing schemes. 相似文献
14.
Geping Song He Liu 《美中经济评论(英文版)》2004,3(9):30-33
This section introduces an asymmetric information model to analyze the interest groups and policy monopoly in social security management, mainly focusing on the relation between the interest groups in the social security products market and the social security government institutions at the central level, namely the major social security policy makers. 相似文献
15.
目前,我国石油供需缺口加大,供需矛盾日益突出。为了弥补石油缺口以满足经济发展的需要,我国实施了石油进口战略。近年来,石油进口的增长导致了我国石油依存度上升。过度集中的进口来源、较小的优质原油进口国选择空间、石油资源后劲不足使我国的石油安全面临着严峻的挑战。本文从重视石油储备、加强油气勘探开发、提高能源利用效率、积极利用国际石油资源等方面提出了构建我国石油安全战略体系的思路框架。 相似文献
16.
英国是世界上最早建立社会保障制度的国家之一。英国建立的多层次养老体系以及一直贯彻的“普遍性”原则、“最低”原则和“个人责任”原则,值得我们这样一个发展中的经济转型国家研究和借鉴。 相似文献
17.
从进城务工人员这个群体的特殊性出发,构建他们的社会保障制度必须要从我国城乡社会保障及其对接角度通盘考虑。通过建立进城务工人员双重社会保障制度,逐步实现城乡社会保障制度的对接。这既关系进城务工人员的权益问题,也关系城乡社会保障衔接问题,更关系着我国社会保障制度一体化目标的实现问题。 相似文献
18.
Food stamp recipients may lack access to larger stores, reducing the availability of nutritious food. Reliance on smaller stores may have undesirable impacts. Policy alternatives include limiting food stamp redemption to larger stores and subsidizing store development. I estimate that limiting redemption to supermarkets and grocery stores, or supermarkets alone, results in losses ranging from $499.2 million to $1.05 billion, or $1.17 billion to $2.44 billion (respectively) annual loss in food stamp recipient welfare nationwide. The impact of improving access is also significant, ranging from $333.6 million to $931.2 million. 相似文献
19.
The Nested PIGLOG Model: An Application to U.S. Food Demand 总被引:1,自引:0,他引:1
A new demand system is introduced, the Nested PIGLOG model, nesting thirteen other demand systems including five that are also new. This new model and its nested special cases are applied to models of U.S. food demand that include food-at-home (FAH), food-away-from-home (FAFH), and alcoholic beverages. Although nested tests and out-of-sample forecasting performance favor generalizing models to a certain degree, statistically insignificant improvements to in-sample-fit and even poorer out-of-sample forecast accuracy undermine further generalizations. Based on a subset of preferred models, FAFH is found to be price and income elastic compared to FAH which is price and income inelastic. 相似文献
20.