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21.
太湖蓝藻预警监测一直是政府及环保部门关注的重点工作并已经成为日常监测任务,但由于数据汇总和日统计评价工作量大,每项指标评判靠人工处理效率明显低下,蓝藻预警监测数据管理系统的开发很好的解决了这一问题.该系统以蓝藻监测和上报的实际业务需求为基础,综合了地表水各项指标的评价功能,并运用网络平台方便灵活地与其他部门共享蓝藻监测信息,极大地提高了综合分析人员工作效率,同时还为环境管理部门提供了更加全面的趋势分析.  相似文献   
22.
李薛晓  程思超  方舟  李先宁 《环境科学》2017,38(5):1904-1910
本研究采用人工湿地型微生物燃料电池处理偶氮染料X-3B,实现降解偶氮染料同步产电的效果.为了构建性能最优的人工湿地型微生物燃料电池(CW-MFC)系统,本研究主要从湿地基质和阴极面积两个方面研究系统构型对去除X-3B同步产电的影响,提高系统性能.研究表明以粒径10 mm、孔隙率30%的小石子作为湿地基质构造的CW-MFC系统微生物生物量最大,去除X-3B效果最好,脱色率高达92.70%,但其产电性能最差.较小的粒径和孔隙率使底层微生物生物量增加,促进X-3B的去除,但随着湿地基质粒径和孔隙率的减小,导致阴阳极营养物质不足,系统传质阻力增加,抑制了系统产电性能.X-3B的去除效果随着阴极面积的增加而提高直到阴极面积为594 cm~2时取得最大脱色率99.41%.当阴极面积继续增加时,CW-MFC系统产电性能上升趋势趋于平缓,X-3B去除效果呈现下降趋势,这是因为阴极反应过快导致更多的阳极电子输送到阴极用于产生电流,与X-3B发生反应的电子减少,阳极成为提高CW-MFC系统性能的限制因素.  相似文献   
23.
针对目前空气质量统计预报方法存在的主要缺陷,本文提出了距离相关系数和支持向量机回归相结合的统计预报方案DC-SVR.利用淮安市2013年1—12月PM_(2.5)观测资料和常规气象观测资料,首先在选入预报当日气象要素的基础上,增加选取前期污染物和气象要素作为预报因子,再采用距离相关系数分季节从预报因子中筛选出重要预报因子,最后采用支持向量机回归对PM_(2.5)浓度值进行逐日滚动统计预报.研究发现,淮安地区气温和气压对PM_(2.5)的距离相关性要高于其他气象要素,夏秋季PM_(2.5)与气象要素的距离相关性较春冬季好.基于距离相关系数和支持向量机回归建立DC-SVR模型,PM_(2.5)的试预报值和实测值的全年相关系数高达0.76,平均偏差仅为1.13μg·m~(-3),平均绝对误差为23.47μg·m~(-3).通过与支持向量机回归、人工神经网络的统计预报效果对比,DC-SVR模型有效降低预报因子维数且能自适应选取最佳参数,预报精度显著优于其他3种统计预报方案,可为业务化预报提供参考.  相似文献   
24.
论可持续发展视野中的农村社会支持   总被引:1,自引:0,他引:1  
本文阐述了如何可持续发展观来指导农村社会支持,并提出在农村社会支持活动中,引进社会保险、社会服务、生态保护和心理培育等新的机制,运用综合性评价指标体系对各种农村社会支持项目及其结果进行经济效益、社会效益和心理效益三个方面的分析。  相似文献   
25.
The growing recognition that climate change mitigation alone will be inadequate has led scientists and policymakers to discuss climate geoengineering. An experiment with a US sample found, contrary to previous research, that reading about geoengineering did not reduce conservatives’ skepticism about the existence of anthropogenic climate change. Moreover, depending on how it is framed, geoengineering can reduce support for mitigation among both conservatives and non-conservatives. When geoengineering is framed as a major solution, people worry less about climate change, leading to reduced mitigation support. When framed as disastrous, people perceived geoengineering as riskier, also leading to a decrease in mitigation support. A more moderate framing of geoengineering as a partial solution is less susceptible to moral hazard effects. Overall, results suggest that geoengineering will not lessen political polarization over anthropogenic climate change, and could undercut support for mitigation efforts. Instead, framing geoengineering as a small piece to solving a big puzzle seems to be the best strategy to weaken this potential moral hazard.  相似文献   
26.
General backcasting as a decision support and planning method starts from desired future states and simulates developments backwards until reaching the present state. Development pathways that reveal steps to be taken to reach a certain future state, and milestones that serve as interim goals, are created during the process. Backcasting has hitherto only been applied in workshops or as a theoretical framework and no spatially explicit backcasting model has previously been established. This paper presents the development of a spatially explicit backcasting model. The proposed model first creates a future scenario utilizing an agent-based model and then simulates backwards. It is implemented using the programming language Python. The model has been applied to a case study for sustainable land-use planning in Salzburg, Austria. The results of the model run show a successful backcasting of land-use classes from a future state back to the present, in 10 year time steps.  相似文献   
27.
Stefan Linde 《环境政策》2018,27(2):228-246
By creating attitudinal rifts among partisan voters, political polarization is expected to negatively affect chances of effectively mitigating climate change. While such expectations generally have found support, less attention has been paid to the opposite claim that political consensus should eliminate the partisan dimension in climate change politics. This study tests this claim by studying how party identification, and party cues specifically, affects public policy attitudes in a context defined by political consensus. Using data from a large online access panel in Sweden, party identification and party cues are shown to matter for policy attitudes even in a consensus context. This effect is not limited to certain issues but is found across a wide range of policies, and the effect of party cues, for a given issue, varies across parties. The implications of this study and areas for future work are discussed.  相似文献   
28.
Nowadays, biodiesel is used as one of the alternative renewable energy due to the increasing energy demand. However, optimum production of biodiesel still requires a huge number of expensive and time-consuming laboratory tests. To address the problem, this research develops a novel Genetic Algorithm-based Evolutionary Support Vector Machine (GA-ESIM). The GA-ESIM is an Artificial Intelligence (AI)-based tool that combines K-means Chaotic Genetic Algorithm (KCGA) and Evolutionary Support Vector Machine Inference Model (ESIM). The ESIM is utilized as a supervised learning technique to establish a highly accurate prediction model between the input--output of biodiesel mixture properties; and the KCGA is used to perform the simulation to obtain the optimum mixture properties based on the prediction model. A real biodiesel experimental data is provided to validate the GA-ESIM performance. Our simulation results demonstrate that the GA-ESIM establishes a prediction model with better accuracy than other AI-based tool and thus obtains the mixture properties with the biodiesel yield of 99.9%, higher than the best experimental data record, 97.4%.  相似文献   
29.
探索资源共享机制研发环境监测技术转化平台   总被引:2,自引:2,他引:0  
阐述了公益与行业共性技术的概念和研发环境监测技术转化平台的必要性,介绍了平台的组织运行机制和网络平台的建设内容,指出该平台对加速科技成果转化、实现监测资源共享具有重要意义.  相似文献   
30.
The development of ecologically sound water allocation strategies that account for the needs of riverine ecosystems is a pressing issue, especially in semiarid river basins. In the Aral Sea Basin, a search for strategies to mitigate ecological and socioeconomic deterioration has been in process since the early 1990s. The Geographic Information System–based simulation tool TUGAI has been developed to support the policy determination process by providing a simple, problem-oriented method to assess ecological effects of alternative water management strategies for the Amudarya River. It combines a multiobjective water allocation model with simple, spatially explicit statistical and rule-based models of landscape dynamics. Changes in environmental conditions are evaluated by a fuzzy habitat suitability index for Populus euphratica, which is the dominant species of the characteristic riverine Tugai forests. Water management scenarios can be developed by altering spatiotemporal water distribution in the delta area or the amount of water inflow into the delta. Outcomes of scenario analysis are qualitative comparisons of the ecological effects of different options for a time period of up to 28 years. The given approach utilizes different types of knowledge, from quantitative hydrological data to qualitative local expert knowledge. The main purpose of the tool is to integrate the knowledge in a comprehensive way to make it available for discussions on alternative policies in moderated workshops with stakeholders. In this article, the modules of the tool, their integration, and three hypothetical scenarios are presented. Based on the experience gained when developing the TUGAI tool, we propose that the general framework can be transferred to other areas where tradeoffs in water allocation between the environment and other water users are of major concern. The potential for a simulation tool to structure and inform a complex resource management situation by involving local experts and stakeholders in the development of possible future scenarios will become increasingly valuable for transparent and participatory resource management.  相似文献   
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