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901.
Sebastien Humbert Yves Loerincik Vincent Rossi Manuele Margni Olivier Jolliet 《Journal of Cleaner Production》2009,17(15):1351-1358
This paper aims to evaluate the environmental burdens associated with spray dried soluble coffee over its entire life cycle and compare it with drip filter coffee and capsule espresso coffee. It particularly aims to identify critical environmental issues and responsibilities along the whole life cycle chain of spray dried coffee. This life cycle assessment (LCA) specifically uses foreground data obtained directly from coffee manufacturers and suppliers. Aside from energy consumption and greenhouse gases emissions, water footprint is also studied in detail, including regionalization of water impacts based on the ecological scarcity method 2006. Other impact categories are screened using the IMPACT 2002+ impact assessment method.The overall LCA results for a 1 dl cup of spray dried soluble coffee amounts approximately to 1 MJ of primary non-renewable energy consumption, to emissions of 0.07 kg of CO2-eq, and between 3 and 10 l of non-turbined water use, depending on whether or not the coffee cultivation is irrigated and wet treated. When considering turbined water, use can be up to 400 l of water per cup. Pouch – and to a lesser extent metal can packaging alternatives – show lower environmental burdens than glass or sticks.On average, about one half of the environmental footprint occurs at a life cycle stage under the control of the coffee producer or its suppliers (i.e., during cultivation, treatment, processing, packaging up to distribution, along with advertising) and the other half at a stage controlled by the user (shopping, appliances manufacturing, use and waste disposal). Key environmental parameters of spray dried soluble coffee are the amount of extra water boiled and the efficiency of cup cleaning during use phase, whether the coffee is irrigated or not, as well as the type and amount of fertilizer used in the coffee field. The packaging contributes to 10% of the overall life cycle impacts.Compared to other coffee alternatives, spray dried soluble coffee uses less energy and has a lower environmental footprint than capsule espresso coffee or drip filter coffee, the latter having the highest environmental impacts on a per cup basis. This study shows that a broad LCA approach is needed to help industry to minimize the environmental burdens directly related to their products. Including all processes of the entire system is necessary i) to get a comprehensive environmental footprint of the product system with respect to sustainable production and consumption, ii) to share stakeholders responsibility along the entire product life cycle, and iii) to avoid problem shifting between different life cycle stages. 相似文献
902.
城市人工湖泊引调水方案优化评估指标体系研究及应用 总被引:1,自引:0,他引:1
针对龙湖这一具有复杂边界的城市人工湖泊,建立基于无结构网格的二维水流水质耦合计算模式,并进行守恒性验证。提出适用于湖泊引调水方案优化的评估指标体系,包括反映调水流态的流场评价指标和反映水质改善效果的水体置换评价指标。利用该评估指标体系进行龙湖引调水方案的优化研究,对不同进水口位置、进水口水量分配和水下地形的调水方案评价指标进行了计算分析,得到推荐的优化方案,即:3个进水口分别布置在水湾4,水湾6和水湾10;进水口水量依次为4.5m^3/s,8.5m^3/s和3.5m^3/s;水下地形在满足龙湖湖区区域水体功能的前提下尽量采用平底或缓坡地形。 相似文献
903.
微生物技术改善河道水质的研究 总被引:1,自引:0,他引:1
该课题是探索直接利用人工培养的微生物改善河道水质的研究。在桂林桃花江河道投放反硝化细菌制剂2个月后,水质有了一定程度的改善,COD和TN的浓度降低,但TP和浊度变化幅度不大。受进水水质和低温天气的影响,反硝化细菌制剂的净化作用及反硝化作用不能充分发挥。 相似文献
904.
Watersheds are under increasing pressure worldwide, as expanding human activities coupled with global climate change threaten the water security of people downstream. In response, some communities have initiated investments in watershed services (IWS), a general term for policy-finance mechanisms that mitigate diverse watershed threats and promote ecosystem-based adaptation. Here, we explore the potential for increasing the uptake and impact of IWS, evaluating what limits its application and how institutional, financial, and informational barriers can be overcome. Our analysis complements the growing literature on individual programs by identifying levers at regional and global scales. We conclude that mainstreaming IWS as a cost-effective strategy alongside engineered approaches will require advances that (i) lower institutional barriers to implementation and participation in IWS; (ii) introduce structural market changes and standards of practice that account for the value of watersheds’ natural capital; (iii) develop practical tools and metrics of IWS costs and benefits; and (iv) share success stories of replicable institutional and financial models applied in varied contexts. 相似文献
905.
906.
水环境质量评价方法的比较分析 总被引:50,自引:0,他引:50
综述了水环境质量评价的发展及目前常用的各种水环境质量评价方法 ,对目前水环境质量评价中的不同方法进行了比较分析 ,针对各种评价方法的优点和不足做出评述。指出水环境评价方法的发展趋势是与计算机技术的有机结合 ,随着计算机技术的发展而不断深化 相似文献
907.
908.
909.
In environmental management there is often discussion on the allocation of responsibilities. Such discussions can continue for a long time and can form an obstacle for effective action. In this article twelve normative principles for the allocation of responsibilities are identified, coming from three different sources: the arguments used in discussions on responsibilities, Dutch and European law, and the environmental management literature. The principles are (1) capacity, (2) lowest social costs, (3) causation, (4) interest, (5) scale, (6) subsidiarity, (7) structural integration, (8) separation, (9) solidarity, (10) transparency, (11) stability (but not standstill), and (12) acquired rights. These principles point to fundamental tensions in environmental management and sometimes conflict with each other. At the same time they may help to resolve conflicts by providing common points of reference that are independent from the often conflicting interests of the discussants. 相似文献
910.
流域水资源开发与饮用水源地保护实例分析 总被引:1,自引:0,他引:1
随着工业化与城市化的发展,流域开发对水资源的需求总量与质量在不断提高。与此同时,工业废水、生活污水、禽畜养殖废水等排放量却在迅速增加,大量未经处理的污废水直接排入周围水体,造成水体利用功能下降,严重危及水资源安全。在潭江流域水资源调查中发现,目前潭江流域面临着流域发展对资源的需求增加与水质下降这一双重问题,流域饮用水源地优先保护与水资源持续利用已成为潭江流域开发研究的重要内容。通过对潭江流域水资源利用现状、特点与存在问题的分析,提出了相应水资源持续利用与饮用水源地保护的对策与措施。 相似文献