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   424篇
  免费   33篇
财政金融   3篇
工业经济   80篇
计划管理   69篇
经济学   42篇
综合类   25篇
运输经济   3篇
旅游经济   12篇
贸易经济   133篇
农业经济   50篇
经济概况   40篇
  2023年   1篇
  2022年   8篇
  2021年   19篇
  2020年   15篇
  2019年   6篇
  2018年   3篇
  2017年   4篇
  2016年   25篇
  2015年   7篇
  2014年   19篇
  2013年   52篇
  2012年   26篇
  2011年   40篇
  2010年   33篇
  2009年   27篇
  2008年   16篇
  2007年   22篇
  2006年   22篇
  2005年   14篇
  2004年   16篇
  2003年   21篇
  2002年   13篇
  2001年   14篇
  2000年   13篇
  1999年   7篇
  1998年   6篇
  1996年   1篇
  1995年   2篇
  1992年   2篇
  1987年   1篇
  1983年   2篇
排序方式: 共有457条查询结果,搜索用时 15 毫秒
1.
本试验以感官评定、菌落总数、pH值和DPPH自由基清除能力为指标,探究不同浓度的壳聚糖溶液处理对以紫花地丁和大麦为主要原料的复合饮料的保质期影响。结果表明,壳聚糖添加量在1.5%时饮料的感官评分较高,菌落总数的增长受到有效抑制,pH值下降受到抑制,具有良好的抗氧化稳定性。研究结果可为紫花地丁复合饮料的研发试验提供理论基础。  相似文献   
2.
Although over 40 jurisdictions have adopted a tax on sugar-sweetened beverages (SSBs) for public health worldwide, it is still debated in many places. Policy processes can influence the prospect of an SSB tax, its design and its public health benefits. To get an insight into such processes, we undertook a case study of the soda tax enacted in France on the 1st of January 2012. Newspaper articles (2003–2013) and institutional documents (2007–2012) were identified using keywords and search engines. Qualitative data extraction and analyses were performed on a thematic and chronological basis, with guidance from Kingdon’s multiple streams theory (MST). Triangulation was enhanced by using complementary sources. This study shows that in August 2011, the French government surprisingly announced a €3.58 cent/L excise tax on SSBs, excluding juices with no added sugars and non-calorically sweetened beverages (NCSBs). As part of a large budgetary plan, the proposal aimed to reduce SSB consumption and raise revenue that was earmarked for health care. Several conditions contributed to opening a policy window: The announcement occurred in the context of severe budgetary deficits; soda tax scenarios had already been discussed at a high level; and the bill was supported by convinced political leaders. Subsequently, the tax successfully passed through the legislative process due to a series of unexpected events, but its public health rationale and design were weakened. The first event was the disorganised reaction by the food industry, despite their sharp opposition to the tax. The next event was the support of the soda tax that came from a majority of Deputies, provided that the revenues would serve another purpose: relieving wage costs in the farming sector. Finally, policy entrepreneurs favoured a compromise to make the tax politically acceptable and legally viable: The tax rate doubled, the scope was extended to NCSBs and revenues were split between health care and agriculture. This study sheds light on influence factors that could be taken into account by public health actors willing to influence soda tax policy processes.  相似文献   
3.
Globally, 43 jurisdictions have implemented a tax on sugar-sweetened beverages (SSBs) for obesity prevention; however, there is significant political resistance to adopting such a policy in Australia. This paper applies Kingdon’s Multiple Streams Framework (MSF) to the case study of an SSB tax in Australia to identify barriers and enablers to policy adoption, and to inform future advocacy strategies in local and international contexts. A systematic search was conducted of scholarly literature, parliamentary documents and media articles relating to an SSB tax. Information retrieved was analysed and integrated under the ‘problem’, ‘policy’ or ‘political’ streams of the MSF. The findings reveal that Australia is a substantial way from having the conditions in place where a tax might be successfully implemented due to industry influence, fragmented advocacy efforts, political opposition to paternalistic policies, conflicting political agendas, and inadequate pressure for change from civil society. Opening a policy window will require a shift in political ownership of the obesity problem, or the coupling of an SSB tax to an alternative problem. The public health community also needs to agree that an SSB tax deserves greater priority, relative to alternative policies for addressing obesity, and to agree on the most effective tax design.  相似文献   
4.
甜菊糖苷作为天然的高甜度、低热量甜味剂,已被广泛应用于食品、饮料中。本文阐述了甜菊糖苷的化学结构、理化功能特性,综述了甜菊糖苷的研究现状以及在饮料工业中的应用,指出其发展前景广阔,为甜菊糖苷的深入研究提供参考。  相似文献   
5.
Young people in the UK consume far above the maximum recommended levels of added sugar. It is likely that neither they nor their parents fully take account of the future health, social and economic costs of this high sugar consumption. This provides a rationale for policy intervention. The majority of young people's added sugar consumption occurs in the home, where purchases are typically made by parents. This means that understanding the purchase decisions of adults is important for policy design, even if the policies aim to reduce the consumption of young people. We discuss the merits of popular policies, including taxes, advertising restrictions and restrictions on the availability of specific foods, and we identify promising avenues for future research.  相似文献   
6.
用高效液相色谱法检测了辣木树不同部位γ-氨基丁酸的含量,结果表明:每100 g样品中,辣木果实、叶、果皮、花、根、籽及茎中的GABA含量分别为378.39、275.64、194.15、96.42、69.14、27.32 mg与0.00 mg。由此可见,辣木树中富含GABA,且幼嫩部位含量较高,本研究可为辣木产品的质量评价、开发利用以及辣木树中GABA的合成部位与运输情况研究提供理论参考。  相似文献   
7.
通过单因素及正交实验,比较高产米曲霉在摇床培养与发酵罐培养中生产曲酸的发酵工艺参数。结果表明,在温度为23℃、发酵天数为9 d、接种量为25%、菌龄为96 h时,摇床发酵的曲酸产量达到最高,最高可达98.6 g·L-1;而发酵罐培养的最佳工艺条件是温度23℃、发酵天数4 d,接种量15%,菌龄96 h时,此条件下曲酸产量可达到99.6 g·L-1。本研究为工业化生产曲酸提了供理论依据。  相似文献   
8.
The main purpose of this paper is to analyse the association between open inbound knowledge strategies and the performance of eco‐innovative firms in the food and beverage industry. We propose a mixed framework based on the eco‐innovation literature and the open innovation approach. We consider the characteristics in a traditional sector based upon a resource‐based perspective. Three types of firms are distinguished in terms of their sales growth in the Spanish food industry from the least to the most successful eco‐innovators. Using multinomial logistic regression models, it is shown that the diversity of collaborators (breadth of external sources of knowledge) and joint adoption of product and process eco‐innovations are positively associated with the probability of achieving high sales growth. Moreover, we find an inverted U‐shaped relationship between the breadth of the external search and firm performance, but only for the group of the most successful firms. Moreover, operational flexibility, knowledge‐based capabilities and company size are also positively related to the group of successful eco‐innovators.  相似文献   
9.
Assessing potential tourists' perceptions is vital to build a destination image and brand capable to attract new and repeated visitors. The increasing popularity of craft beverage tourism in recent years is incentivizing destinations to (re)design their offerings and (re)brand their image based on their craft beverages. This study investigated how the image of an emerging craft beverage tourism destination (Ica, Peru) is formed among potential tourists by inducing cognitive image (knowledge presented through picture-text dyads) of Ica's iconic resources, staple craft beverage (pisco), and resources associated with its production. Additionally, it measured the impact of local resources' characteristics, affective image, and personal characteristics on conative image (interest to visit and willingness to recommend) at different intervention stages. Results indicate that pisco-related resources are powerful enough to motivate travel, and that the characteristics of a mix of resources should be combined with beverage-specific information when developing branding strategies for craft beverage tourism destinations.  相似文献   
10.
国内外精对苯二甲酸生产发展概况   总被引:1,自引:0,他引:1  
本文对国内外精对苯二甲酸生产技术现状、发展动向、以及市场供需状况作了概要叙述.  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