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31.
Impressions and purchasing intentions of Japanese consumers regarding pork produced by ‘Ecofeed’, a trademark of food‐waste or co‐product animal feeds certified by the Japanese government, were investigated by a questionnaire on the Internet. ‘Ecofeed’ did not elicit specific impressions as compared to domestic, imported, Kurobuta (in Japan), and specific pathogen‐free (SPF) pork. Purchasing intent for ‘Ecofeed’ pork was the second lowest of the five pork products. Knowledge and purchasing experience regarding ‘Ecofeed’ pork was the lowest of the five pork products. Respondents were classified into four categories according to their impressions of ‘Ecofeed’ pork. The largest category of respondents did not have any specific impression of ‘Ecofeed’ pork and had little knowledge of pork farming. A category that had a positive impression for ‘Ecofeed’ pork had high knowledge of the pork farming system. In order to establish ‘Ecofeed’ pork in Japan, our results suggest that information disclosure and education about ‘Ecofeed’, its certification system, environmental benefits and the current self‐efficiency ratio of animal feed, are needed.  相似文献   
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Since the 1990s, the mountain pine beetle (MPB) population has exploded in western Canada. In national parks, MPB has the potential to impact visual quality and safety of visitors, and to spread beyond park boundaries to the industrial forest landbase. Control measures have been initiated in some parks to lessen these impacts. A study was undertaken to examine public attitudes, knowledge, issue salience, and management preferences for MPB in Banff and Kootenay national parks. Data were collected by mail survey in 2003 from 1385 residents living in or near the parks. MPB was an important issue for the majority of respondents and they had low knowledge of MPB, expressed negative attitudes towards it, and supported measures to control it. Preferred control measures included those directed at the current infestation. Proactive approaches in uninfested forests were generally not supported. Issue salience and knowledge were the best predictors of attitudes toward the MPB. Attitudes were the best predictors of support for no intervention in beetle infestations in national parks. Management implications include the lack of knowledge and support for natural disturbance and ecological integrity policies in national parks.  相似文献   
34.
对金融消费者进行保护的最根本原因是金融交易中的金融机构处于信息优势地位而引发的道德风险问题损害了处于弱势地位的金融消费者的合法权益。然而,通常容易被忽视的是当金融消费者处于信息优势地位及过度的金融消费者保护而引发的道德风险问题。通过运用经济学当中的信息不对称理论、委托代理理论对金融交易中产生的双重道德风险进行分析,更好地防范双重道德风险的产生,保护金融消费者的权益。  相似文献   
35.
Plants are well known to incorporate pesticides into bound and unextractable residues that resist solubilization in common laboratory solvents and are therefore not accessible to standard residue analysis. A characterization of such residues has been proposed for incorporation rates above trigger values of 0.05 mg kg(-1) parent pesticide equivalents, or percentage values of 10% (United States Environmental Protection Agency, 1995) or 25% (Commission of the European Communities, 1997) of the total radioactive residue. These trigger values are often exceeded. The present review describes the current status of the chemical characterization and animal bioavailability of bound and unextractable residues that may be xenobiotic in nature or result from natural recycling of simple degradation products. The latter case represents a mechanism of detoxification. Bound residues have been shown to be covalent or non-covalent in nature. With regard to the plant matrix molecules involved, incorporation into proteins, lignins, pectins, hemicelluloses and cutins has been demonstrated, and four covalent linkage types are known. Animal feeding experiments have revealed cases of low as well as high bioavailability. Many of the studies are limited by experimental uncertainties and by results only being reported as relative percentage values rather than absolute exposure. A preliminary value of absolute exposure from bound and unextractable residues is derived here for the first time from eight case studies. The mean exposure (ca 1.5 mg kg(-1) pesticidal equivalents) exceeds some of the existing maximum residue levels (MRLs) of residual free pesticides that are typically in the range of 0.05-1 mg kg(-1). A mathematical framework for the correction of current maximum residue levels is presented for cases of highly bioavailable bound residues. As bound pesticidal residues in food plants could represent a source of significant consumer exposure, an experimental test scheme is proposed here. It consists of basic chemical characterization, model digestibility tests and, in exceptional cases, animal bioavailability and additional toxicological studies.  相似文献   
36.
中国水禽产业发展的现状和问题及对策   总被引:4,自引:2,他引:2  
本文以水禽产业现有的信息数据为基础,结合在全国范围的实地调查数据,对我国水禽产业整体发展现状及存在的问题进行研究。结果显示:近年来中国水禽产业发展现状表现以下特征:水禽养殖数量稳中有升,产品产量逐年递增;产业化水平日益提高,产业链由单一的饲养业向加工、物流等产业延伸;水禽产业呈现优势产区集中分布的特征,由资源优势向技术、资本优势转变;水禽产品消费需求趋于饱和边缘,产品结构亟待升级换代以扩展消费需求空间。针对水禽产业发展存在的信息和数据不清,对宏观决策与市场调控带来困难;行业标准和统一规范缺失;产业经营利润分配不均;水禽饲养技术相对落后,水资源环境污染严重等问题,提出了相应的对策。  相似文献   
37.
The presented planning method searches for an optimal combination of treatment schedules for forest compartments by maximizing, in an iterative manner, an additive utility function. The variables of the utility function can be selected from parameters that are associated to the whole forest area, such as; amount of removal, costs, income, or volume of the growing stock. Partial utility functions are developed for each objective variable the total utility being a weighted sum of the partial utilities. The weights of the objectives and the partial utility functions are estimated using the Analytic Hierarchy Process. Development and estimation of the utility function makes decision analysis an integral part of the planning process. The method was used with a non‐industrial private forest, but the approach is also applicable to many other forest planning situations.  相似文献   
38.
姜友雪 《茶叶》2013,39(3):146-148,152
为了研究当前哪些因素影响城市居民茶叶消费行为,为茶产业产学研提供理论依据,本文通过采纳城市居民茶叶消费行为的调查数据,使用计量经济软件Eviews3.1,运用线性模型,进行普通最小二乘法估计。实证研究结果表明:月总收入、家庭人口数、饮茶年份与消费者的茶叶消费支出成正相关,教育水平与茶叶消费支出成负相关,收入是影响茶叶消费支出弹性的主要因素。  相似文献   
39.
食用农产品召回面临经营者主动召回不足和行政机关责令召回时效滞后两大困境。有学者提出以消费者参与尤其是起诉来敦促召回,但梳理司法判例发现,起诉召回影响力微弱,诉讼不宜作为消费者参与食用农产品召回的首选途径。发挥消费者协会的群体力量、招募专家消费者参与召回立法、由消费者协会代替个体消费者监督召回过程,路径更为可行。为给消费者协会参与召回实施提供资金保障,有必要令召回义务人预留民事赔偿准备金,以备付召回期结束后消费者求偿,从食品安全行政罚款中协调预扣资金,与准备金余额一起专供消费者协会招募专家消费者参与召回立法。  相似文献   
40.
Farmers’ contract breach behavior is cited as one of the major stumbling blocks in the sustainable expansion of contract farming in many developing countries. This paper examines farmers’ contract breach decisions from the perspective of time preferences. The empirical analysis is based on a household survey and economic field experiments of poultry households participating in contract farming conducted in Jiangsu Province, China. A discounted utility model and a maximum likelihood technique are applied to estimate farmers’ time preferences and the effect of time preferences on contract breach in the production and sales phases are explored with a bivariate probit model. The results show that, on average, the poultry farmers in the sample are generally present biased and impatient regarding future utility. The regression results show that farmers with a higher preference for the present and a higher discount rate are more likely to breach contracts, and time preferences play a greater role in the production phase than in the sales phase. When considering heterogeneity, specific investments and transaction costs promote contract stability only for farmers with a low degree of impatience. Moreover, compared with large-scale farmers, small-scale farmers’ contract breach decisions are more significantly affected by their time preferences. These results have implications for contract stability policies and other issues that are impacted by the linking of behavioral preferences to agricultural decisions.  相似文献   
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