全文获取类型
收费全文 | 928篇 |
免费 | 43篇 |
国内免费 | 187篇 |
专业分类
安全科学 | 62篇 |
废物处理 | 7篇 |
环保管理 | 216篇 |
综合类 | 361篇 |
基础理论 | 159篇 |
环境理论 | 2篇 |
污染及防治 | 171篇 |
评价与监测 | 15篇 |
社会与环境 | 92篇 |
灾害及防治 | 73篇 |
出版年
2024年 | 1篇 |
2023年 | 14篇 |
2022年 | 46篇 |
2021年 | 44篇 |
2020年 | 42篇 |
2019年 | 37篇 |
2018年 | 38篇 |
2017年 | 70篇 |
2016年 | 57篇 |
2015年 | 38篇 |
2014年 | 42篇 |
2013年 | 105篇 |
2012年 | 54篇 |
2011年 | 47篇 |
2010年 | 43篇 |
2009年 | 48篇 |
2008年 | 43篇 |
2007年 | 61篇 |
2006年 | 50篇 |
2005年 | 44篇 |
2004年 | 22篇 |
2003年 | 39篇 |
2002年 | 36篇 |
2001年 | 22篇 |
2000年 | 24篇 |
1999年 | 8篇 |
1998年 | 14篇 |
1997年 | 8篇 |
1996年 | 12篇 |
1995年 | 8篇 |
1994年 | 5篇 |
1993年 | 8篇 |
1992年 | 5篇 |
1991年 | 7篇 |
1990年 | 5篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有1158条查询结果,搜索用时 15 毫秒
991.
《Journal of Environmental Policy & Planning》2012,14(3):185-195
Risks related to food production and consumption are not a recent phenomenon. Through agricultural practices, the transport of agricultural and food products, the processing of food, its storage, and finally the consumption of food, risks have been externalized, mediated, contested and ingested. But agrofood systems have also been paralleled by routinized practices and institutions that attempt to reduce risks and sustain trust among the many actors involved in these food regimes. However, both the (definition of) food risks and the institutions and discourses used to dispel anxiety and build trust are far from stable throughout time. In the contemporary modern world-order, food risks and the practices and institutions dealing with these risks reflect the significant transformations in the agrofood system, the changing nature of the risks involved in food production and consumption, and the modifications in scientific risk assessment and risk management. This article provides an overview of the current debates, discussions and practices on actual and potential institutional transformations that parallel the emergence, assessment and management of food risks in reflexive modernity. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
992.
《Journal of Environmental Policy & Planning》2012,14(2):149-162
Contemporary analysis of the food sector has failed convincingly to link production to consumption, and it has not provided a sociological account of such links. This paper makes a provisional attempt to begin such an analysis and does so by examining the case of the market for organic food in Tuscany. It proposes that the ‘pioneers’ of organics in this region constituted a new food movement that succeeded in opening up a new market. However, this market could only be successfully expanded once other actors were enrolled in the market-making process, notably state agencies and supermarkets. The regional government, through new regulations and specific initiatives, integrated organic foods into rural development policy, thereby assisting producers in the process of conversion. Supermarkets co-operated in the implementation of these policies and made space for Tuscan organic products in their stores. So while the ‘pioneers’ began the process of market building, these later entrants were crucial to the stabilization and expansion of the organic sector in Tuscany. Thus, it can be concluded that the emergence of these new ‘markets’ for nature can only be adequately explained by analysing the full range of actors. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
993.
Assessment of vancomycin resistance transfer among enterococci of clinical importance in milk matrix
《Journal of environmental science and health. Part. B》2012,47(12):925-929
AbstractDissemination of vancomycin resistance in enterococci has been associated with horizontal transfer of mobile genetic elements. Aim of the study was to evaluate if milk matrix is a suitable environment to support transferability of vancomycin resistance (vanA) gene from clinical vancomycin-resistant Enterococcus faecium to vancomycin-sensitive Enterococcus faecalis. Enterococci strains were firstly screened for the presence of cpd (inducible sex pheromone determinant) gene, vanA and tetL genes (vancomycin and tetracycline resistance markers, respectively) and the gelE (extracellular metalloendopeptidase) gene to define the mating pairs. Based on these selection markers, we investigated the transferability of eight plasmid-borne vanA harbored by E. faecium (vanA+, cpd-, tetL- and gelE-) into two E. faecalis (vanA-, cpd+, tetL?+?and gelE+) recipient strains in milk matrix. The strains were mated in a 1:1 ratio in 7% reconstituted milk and incubated at 37?°C. Transconjugants emerged from all 16 matings within 2?h of incubation and were evidenced by dual antibiotic resistance (vancomycin and tetracycline). The vancomycin-resistance of trasconjugants was maintained even after ten subsequent passages on nonselective medium. Transconjugants were positive for vanA, tetL and gelE genes. This study indicates milk matrix as suitable environment to support gene exchange between Enterococcus species. 相似文献
994.
For more than a decade the humanitarian community has been mandated to mainstream gender in its response to crises. One element of this mandate is a repeated call for sex-disaggregated data to help guide the response. This study examines available analyses, assessments and academic literature to gain insights into whether sex-disaggregated data are generated, accessible and utilised, and appraised what can be learned from existing data. It finds that there is a gap between policy and practice. Evaluations of humanitarian responses rarely refer to data by sex, and there seems to be little accountability to do so. Yet existing data yield important information, pointing at practical, locally-specific measures to reduce the vulnerability of both males and females. This complements population-level studies noting the tendency for higher female mortality. The study discusses some possible obstacles for the generation of data and hopes to spur debate on how to overcome them. 相似文献
995.
Sara Spendrup Elin Röös Emma Schütt 《Environmental Communication: A Journal of Nature and Culture》2019,13(1):87-103
To facilitate the choice of more sustainable animal-based products in the diet, a Swedish meat guide providing complex, multi-layered environmental information to non-experts has been developed. This study evaluated reception of this guide by consumers. In five focus groups, participants (“interested consumers”) carried out a joint environmental and animal welfare ranking assignment to test understanding and use of the guide. The type and detail of indicators (e.g. carbon footprint) in the meat guide suited the audience. The guide stimulated discussion on ethical issues and quality aspects of meat, revealed perceived obstacles to reducing meat consumption and provided an understanding that any food product chosen comes with trade-offs. 相似文献
996.
Community-based urban aquaponics enterprises represent a new model for how to blend local agency with scientific innovation to deliver food sovereignty (FS) in cities, re-engaging and giving urban communities more control over their food production and distribution. Little is known, however, about the factors and outcomes that determine the success or failure of these enterprises. This paper explores stakeholder experiences of building community-based urban aquaponics enterprises to understand the internal and external factors that impact on their success or failure. We draw upon existing FS, social enterprise and aquaponics literature, to identify factors in the related area of community-based urban agriculture. For exploring these factors, we use a comparative case study methodology for two cases in Milwaukee and Melbourne, conducting in-depth interviews with key stakeholders, exploring their relative contexts, objectives and structure. Based on these findings, we highlight the challenges and suggest relevant indicators for establishing an urban aquaponics enterprise. 相似文献
997.
Megan Elizabeth Betz 《Local Environment》2016,21(11):1420-1434
Local food systems and farmers' markets across the USA have experienced unprecedented growth and development in the past 20 years. While scholarship has examined participant demographics and motives for engaging in farmers' markets, few studies have considered the coupled nature of those attending the markets with institutional governance systems used for market coordination. This study examined participation in farmers' markets under the framework of high and low market governance systems, specifically considering the demographics, values for local foods, motives for attending farmers' markets, and outcomes of the experience based on the dichotomous governance classification. Governance was characterized using four attributes: market rules or policies, paid employee(s), a rule governing geography of food origin, and affiliation with an organisation or agency. Our results suggest that market governance may impact (1) which consumers attend the market, (2) motives among those who attend the market, and (3) satisfaction outcome levels among market participants. By better understanding how the emerging governance system impacts who ultimately attends the market (and the outcomes of the experience), agencies coordinating farmers' markets and market managers can ultimately improve the market's reach and experience with greater intentionality. 相似文献
998.
More than something to hold the plants up: soil as a non-human ally in the struggle for food justice
Hazel Ferguson the Northern Rivers Landed Histories Research Group 《Local Environment》2016,21(8):956-968
Healthy, fertile soil is the material of life itself. It is chemically, biologically and physically structured to support the growth of healthy, environmentally sustainable foods. Recent years have seen a resurgent focus on soil science in Australia. Yet, the influence of soil in the politics of food systems has received comparatively little attention, despite long awareness in farming communities of how the natural world shapes farmers’ choices and possible actions. Drawing on work with SoilCare, a Landcare group with a focus on soil processes in the Northern Rivers of New South Wales, this paper explores the usefulness of approaching soil as an actor in food systems. Taking a participatory approach, and drawing on recent work on new materialisms, we argue that soil can be understood as an important ally in the struggle to shape a just and sustainable food system. While this work is intended to test this idea through a modest local case study, it may point to important new avenues for investigation in food politics. 相似文献
999.
Deep structural and sustained change is necessary to tackle contemporary environmental challenges. How such change emerges and can be governed has been explored through the notion of sustainable innovation journeys. To date research had conceptualised such journeys as transitions to more sustainable socio-technical systems, e.g. mobility, shelter, food and farming. However, there is a paucity of how innovation proceeds in firms as part of sustainable innovation journeys. This paper begins to address this gap in knowledge. A longitudinal case study was completed of a medium-sized food-processing firm in the UK. Qualitative data were collected using ethnographic methods such as participant observation. Drawing on practice theory, a conceptual framework was developed which enabled us to explore and make sense of the firm's sustainable innovation journey conceptualised as practices. Findings show that we can usefully treat a firm as a flow of practices that either resist or otherwise accommodate new practices deemed more sustainable. 相似文献
1000.
A. O. Mehder Mohamed A. Dastageer Yusuf B. Habibullah Mohammed A. Iqbal Luqman E. Oloore 《Journal of environmental science and health. Part. B》2016,51(6):358-365
Laser induced breakdown spectroscopy (LIBS) was applied for the detection of carcinogenic elements like bromine in four representative brands of loaf bread samples and the measured bromine concentrations were 352, 157, 451, and 311 ppm, using Br I (827.2 nm) atomic transition line as the finger print atomic transition. Our LIBS system is equipped with a pulsed laser of wavelength 266 nm with energy 25 mJ pulse?1, 8 ns pulse duration, 20 Hz repetition rate, and a gated ICCD camera. The LIBS system was calibrated with the standards of known concentrations in the sample (bread) matrix and such plot is linear in 20–500 ppm range. The capability of our system in terms of limit of detection and relative accuracy with respect to the standard inductively coupled plasma mass spectrometry (ICPMS) technique was evaluated and these values were 5.09 ppm and 0.01–0.05, respectively, which ensures the applicability of our system for Br trace level detection, and LIBS results are in excellent agreement with that of ICPMS results. 相似文献