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261.
Growing dissatisfaction with the globalised food system, articulated on the behalf of both producers and consumers, has caused a variety of public debates surrounding the ethics of food production and consumption to become increasingly visible in society over the last two decades. Simultaneously, farmers’ markets (FMs) and other forms of direct marketing have experienced a noteworthy increase in participants, indicating an emerging demand for an alternative to conventional food networks, alternatives that are often perceived as providing a more just and moral relationship to food production and consumption. This study examines consumer and producer motivations for participation in FMs and opinions towards conventional and alternative agriculture in order to elucidate what (if any) values and morals are shared among producers and consumers. This study draws upon the theoretical framework of moral economy to understand whether these shared values suggest FM participants are working to co-create an alternative economy based on “moral” principles such as fairness, justice, and reciprocity. This mixed-methods study consists of consumer surveys (N?=?377) and semi-structured interviews with producers (N?=?17) from five FMs in the state of Delaware. The results suggest that producer and consumer motivations to participate in FMs, particularly a shared emphasis on social value, are indicative of a sense of moral economy. However, this moral economy is complicated by tension towards consumers and the alternative food movement more generally expressed on behalf of producers.  相似文献   
262.
This paper sheds critical light on the motivations and practices of community gardeners in relatively affluent neighbourhoods. The paper engages with community garden, alternative food and domestic garden literatures, to understand how people fit food production into their everyday lives, how they develop relationships to plants and how these in turn shape relations between people in a community group. The paper draws on participant observation and semi-structured walking interviews conducted at three community gardens in Sydney, Australia. The paper concludes that to fit community gardening into busy lives, people strategically choose plants with biophysical qualities that suit personal as well as communal circumstances and objectives. The paper shows how community is relationally constituted through the practices of growing and sharing food. Tensions might arise through the practices of growing food on communal and private plots and the taking and giving of food, but it can also encourage people to reflect on community food production and on their roles as individuals in a community group.  相似文献   
263.
How science and policy interact has been a major research focus in the International Relations (IR) tradition, using the epistemic community (EC) concept, as well as in the alternative perspective of Science and Technology Studies (STS). Should science be autonomous and as apolitical as possible in order to ‘speak truth to power’, as suggested by EC or should the inevitable entanglement of science and politics be accepted and embraced so as to make advice more conducive to negotiating the explicit travails of political decision-making as suggested by STS? With this point of departure, we compare similarities and differences between science–policy interactions in the issue areas of eutrophication and fisheries management of the Baltic Sea. To examine how knowledge is mobilised, the concepts of ‘uncertainty’ and ‘coherence’ are developed, drawing on both EC and STS thinking. We then reflect on the explanatory value of these approaches in both cases and discuss how a separation of science and policy-making in the pursuit of achieving scientific consensus leads to ineffectual policies. Drawing on STS thinking, we urge for a re-conceptualisation of coherence in order to accommodate a more reflexive practice of science–policy interactions.  相似文献   
264.
Cost–benefit analysis has been criticised on the grounds that it cannot compute the value of environmental goods whose value constitutively defies monetary valuation. Two forms of incommensurability make monetary valuation problematic: constitutive incommensurability and quantitative incommensurability. These pose a threat only to shadow pricing, and not the formation of prices in an actual market. Where property rights to environmental goods are appropriately assigned, the prices that form reflect the actual uses persons put them to, given their value commitments. In a real market, the formation of prices does not depend upon the assignment of cardinal values via monetary valuation; rather, the formation of prices is a side effect of the way in which environmental goods are used. A property right gives one the right to reject terms of exchange one deems inappropriate. Where sale of an environmental good is deemed inappropriate, it is kept out of the cash nexus. Incommensurability therefore precludes cost–benefit analysis, but not markets in environmental goods where property rights are appropriately allocated.  相似文献   
265.
The effect of 24-epibrassinolide seed soaking on imidacloprid residues in green pods and mature seeds of Brassica juncea L. plants was investigated. The activities of the antioxidative enzymes glutathione-S-transferase, glutathione peroxidase, glutathione reductase, ascorbate peroxidase and guaiacol peroxidase, and the content of glutathione were determined. Imidacloprid residues in green pods were analyzed and quantified by gas chromatography-mass spectrometry, revealing that 24-epibrassinolide treatment resulted in a decrease of residues by almost 30%. In mature seeds, no pesticide residues were detected. Activities of all the antioxidative enzymes and glutathione content were found to be high in plants grown in soil amended with 300 mg imidacloprid kg?1 soil, but pre-soaking with 100 nmol L?1 24-epibrassinolide further enhanced the activities of all these enzymes and the glutathione content.  相似文献   
266.
Marine constructions are highly vulnerable to climate change and sea-level rise (SLR), leading to increased risk rates of destruction and the potential closure of ports, harbors, and marinas along the coast. We present a cost-adjustment analysis for such constructions along the south-eastern Mediterranean coast, which takes into account the physical characteristics of the constructions, and environmental uncertainty factors. At 0.5 m SLR, the estimated adjustment cost is USD 280 million, and at 1 m SLR, the estimated cost is USD 505 million. These costs are equivalent to 0.091% and 0.165% of the Israeli gross domestic production, respectively. Although high, these adjustment costs are lower than the costs of future damage that will accrue if we fail to act. This implies that the adaptation-policy approach to controlling for the risk of SLR will provide benefits to the economic marine sectors and the public at large.  相似文献   
267.
Fe/AC催化湿式过氧化氢氧化处理焦化废水   总被引:2,自引:2,他引:0  
采用浸渍法制备了负载型Fe/AC催化剂,通过比表面积、热重等方法对其进行了表征,并以焦化废水中的主要污染物苯酚、喹啉、氨氮为研究对象进行催化湿式过氧化氢氧化处理(CWPO),考察了Fe/AC催化剂的制备条件和CW-PO处理工艺条件对Fe/AC催化剂的稳定性和催化活性的影响。结果表明:催化剂活性组分的负载量、焙烧温度、初...  相似文献   
268.
流光放电氧化亚硫酸盐的研究   总被引:1,自引:0,他引:1  
使用气体放电等离子体对亚硫酸盐进行氧化,考察了各种因素对于亚硫酸盐氧化的影响.实验表明,随着初始浓度,喷雾流量,pH值的增加,亚硫酸盐氧化率降低;亚硫酸盐氧化率随着循环次数的增加而增加.  相似文献   
269.
负载型纳米复合半导体WO_3-TiO_2/AC光催化降解刚果红废水   总被引:1,自引:0,他引:1  
采用溶胶-凝胶-浸渍-焙烧法制备了负载型纳米复合半导体WO3-TiO2/AC光催化剂,以偶氮染料刚果红为目标降解物,通过正交实验优化了刚果红废水的降解条件,并对其光催化动力学进行了探讨.结果表明,刚果红废水的最佳降解条件为:催化剂投加量10 g/L,pH=7,H2O2用量为3.5 mL/L.在最佳条件下,当刚果红废水起始浓度为40 mg/L时,反应120 min后,刚果红溶液的去除率可达95.21%,较相同条件下TiO2/AC对刚果红染料的降解率提高了19.57%.光催化剂对刚果红的光催化降解符合Langmuir-Hinshelwood(L-H)模型.  相似文献   
270.
Developing nations have tended to have been overlooked in studies of climate reporting. This study is based upon a content analysis of three daily newspapers in the Philippines to examine climate change coverage compared to reporting by Western wire services. In addition, the study draws on individualist–collectivist theory to theorize about differences in reporting between the Philippine and Western wire sources. Despite the historic influence of the American news system on Philippine journalism, the study finds that Western journalistic norms do not describe Philippine climate reporting well and that Filipino-penned articles are more likely to include the value of collectivism rather than individualism. This suggests that national cultural differences may be reflected in climate reporting.  相似文献   
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