首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1095篇
  免费   24篇
  国内免费   82篇
安全科学   69篇
废物处理   26篇
环保管理   263篇
综合类   410篇
基础理论   84篇
污染及防治   168篇
评价与监测   99篇
社会与环境   45篇
灾害及防治   37篇
  2024年   3篇
  2023年   9篇
  2022年   19篇
  2021年   32篇
  2020年   34篇
  2019年   15篇
  2018年   15篇
  2017年   32篇
  2016年   48篇
  2015年   36篇
  2014年   49篇
  2013年   46篇
  2012年   58篇
  2011年   98篇
  2010年   40篇
  2009年   73篇
  2008年   82篇
  2007年   62篇
  2006年   68篇
  2005年   37篇
  2004年   44篇
  2003年   39篇
  2002年   32篇
  2001年   28篇
  2000年   31篇
  1999年   26篇
  1998年   15篇
  1997年   21篇
  1996年   13篇
  1995年   17篇
  1994年   18篇
  1993年   4篇
  1992年   8篇
  1991年   5篇
  1990年   1篇
  1989年   2篇
  1988年   3篇
  1987年   5篇
  1986年   8篇
  1985年   6篇
  1984年   6篇
  1983年   4篇
  1982年   3篇
  1980年   1篇
  1979年   2篇
  1977年   1篇
  1973年   2篇
排序方式: 共有1201条查询结果,搜索用时 172 毫秒
271.
传统水质监测方法耗时且费力,而基于高光谱的水质监测技术可实现对水质的快速、直观、原位监测。以扬州古运河三湾段为研究区域,基于无人机高光谱成像仪与水质走航监测船相配合,采用空地协同模式和偏最小二乘回归算法对总磷(TP)、总氮(TN)、氨氮(NH3-N)、高锰酸盐指数(IMn)4个水质参数进行定量反演研究。结果表明:该反演模型的决定系数(R2)为91%~97%;拟合效果依次为NH3-N>IMn>TN>TP;各指标反演误差绝对值为0.2%~4%。该方法具有较好的反演效果,可快速、准确地获取城市河道水质分布情况,适用于城市水环境监测。  相似文献   
272.
D. Fleury 《Safety Science》1998,29(3):217-228
Road planning is based on technical rules, know-how acquired from experience and professional expertise. A more ergonomics approach to road planning and safety analyses the psychological procedures used by the drivers. Every intervention on road network has an influence on safety. Increasing the coherency of all the interventions in the same area is the only possible way of producing areas with a better level of security. This paper deals with safety procedures, diagnostics and tools which can be used at different levels of intervention.  相似文献   
273.
Extensive green areas generate a recognizable green identity of Ljubljana. Due to the challenges of climate change and urbanization the city's spatial policy highlights revitalization of degraded urban areas, preserving the quality and scope of the existing green network and the protection of multifunctional natural areas surrounding the city. Article describes the project of Rakova Jelša Park as a good example of these policies. With an NGO initiative a former degraded area with illegal dumping and non-indigenous vegetation was transformed into recreational park with increased biocultural diversity. Important lesson of the project is that opening up space for public use not only prevents degradation, but also improves the quality of urban ecosystems. One of the challenges for the city's future sustainable ecosystem development will be a more active cooperation with its citizens in the green infrastructure policy and later also a partial transfer of responsibility for green areas to them.  相似文献   
274.
Currently, most tools, guidelines and benchmarks for urban adaptation raise awareness on climate change impacts, assess the city’s vulnerability and/or address the need for adaptation on a policy-level. However, tools that have the ability to implement adaptation solutions in the actual urban planning and design practice seem to be missing. We developed and tested the Adaptation Planning Support Toolbox (APST) to fill this gap. This toolbox supports local policymakers, planners, designers and practitioners in defining the program of demands, in setting adaptation targets, in selecting from more than 60 blue, green and grey adaptation measures and with informed co-creation of conceptual adaptation plans. The APST provides quantitative, evidence-based performance information on (cost)effectiveness of adaptation measures regarding climate resilience and co-benefits. The APST can be used design workshops, to feed dialogues among stakeholders on where and how which ecosystem-based adaptation measures can be applied. Applications of the AST in various settings and context in cities on different continents have illustrated the added value of the toolbox in bringing policy and practice together with help of science. With more and more cities worldwide that will make the step from policymaking to actual adaptation-inclusive urban (re)development practice we foresee a growing demand for such tools.  相似文献   
275.
"洋垃圾"是当前最严重的全球环境问题之一。我国作为"洋垃圾"的主要输入国,生态环境安全正遭受严重的威胁。海关管控"洋垃圾"的力度和水平是影响"洋垃圾"走私进境规模及其生态环境破坏程度的关键因素。虽然我国海关对"洋垃圾"的管控水平不断提高,但相比"洋垃圾"数量庞大的走私规模和日趋严重的环境污染,现有的海关风险管控举措无法保障减少乃至杜绝"洋垃圾"进境目标的实现。本文从"洋垃圾"的品类细分、对生态环境造成的可能污染分类开始,结合"洋垃圾"污染的实际案例,总结出我国海关风险管控缺失的危害,提出基于AHP(Analytic Hierarchy Process)层次分析方法,对"洋垃圾"海关风险进行等级评判,将"洋垃圾"海关风险因素从企业和货物两个方面分解为四个因素,以此来分析"洋垃圾"的海关风险。采用多级模糊综合评判法确定各指标权重并构建"洋垃圾"海关风险等级评判模型,并以2013年海关"绿篱"行动对该模型进行可行性验证,进而提炼出海关风险管控三大体系,即海关监管、海关稽查和海关缉私风险管控体系,并据此总结出这三个层面的风险管控措施,每层措施又分别给出相应的分级动态调整管控手段。这些海关风险管控措施和手段对于防止"洋垃圾"进境对我国生态环境的破坏起到积极的作用。  相似文献   
276.
The need for environmental and urban planning reached a critical point in the year 2007, when one-half of the world's population could be defined as living in cities. Urbanisation in India is also increasing at a fast rate. Urban chaos in India, emanating from the continuous ignorance of fragile ecosystems, calls for the reshaping of existing cities as ‘eco-cities’. The ‘eco-city’—a well-known concept in the western world—is new to the Indian context. While western connotations of eco-cities should not be discarded outright in the context of India, core concerns vary significantly for obvious reasons. Recognising two facts—firstly, eco-city development is altogether a fresh approach to human settlement development in India, and, secondly, the manifold increase in the vulnerability of cities—this paper discusses documented good practice, reinforcing evolution towards the eco-city vision. Lessons drawn from the examples cited are further deconstructed in the light of their contribution to urban risk reduction, which provides direction to appreciating the ‘disaster-resilient eco-community’ concept in Puri, a coastal city in India. Further, this paper attempts to unravel existing community-based practices in Puri, which are boon to the local environment and invariably reduce disaster risk. These seemingly modest neighbourhood initiatives symbolise immense societal wealth, which can be calibrated appropriately for reducing urban environmental risk as well. This paper also illustrates how a ‘disaster resilient eco-community’ approach is inevitable in the present and future contexts not only to preserve sustainable development gains but also to secure human well-being.  相似文献   
277.
城市地铁工程主要穿越城市商业区和居民聚居区 ,施工过程中的安全技术问题可能对地表环境产生严重影响 ,甚至诱发地面塌陷等灾害发生。笔者结合广州地铁二号线鹭江站的施工实践 ,研究了城市地铁工程的施工安全技术 ;探讨了地铁车站施工安全监测中的维护桩变形、土体变形、支撑结构的受力状况、地下水水位、地下管线沉降和位移监测的实施细则 ;突出了对折返线施工过程的监测 ;研究了施工安全保障技术方法体系 ;对施工现场安全技术、施工工艺安全技术进行了深入分析 ;明确了基坑开挖、洞室掘进、空中作业等不同类型的施工场地和人工挖孔、爆破、模筑混凝土、钢支撑安装、防水层施做等各种施工工艺的安全保障技术方法 ;建立了安全施工和安全管理措施方法体系。  相似文献   
278.
城市生活垃圾处理现状及发展趋势   总被引:6,自引:0,他引:6  
针对我国目前城市生活垃圾的现状和特点,探讨了城市垃圾产生量随年度变化的规律,垃圾产生量与人口和GDP的关系,分析了我国主要城市的垃圾组分。简要介绍了处理城市生活垃圾的几种方法和处理技术的发展趋势。  相似文献   
279.
城市火灾扑救调度指挥过程的Petri网模型研究   总被引:3,自引:1,他引:2  
在经典Petri网理论的基础上,发展了一类有色非自主Petri网方法,用以建立城市火灾扑救调度指挥过程的仿真模型,并通过实例,对火警出动等级判断规则及按火警出动等级调派车辆规则进行了初步仿真研究。  相似文献   
280.
张毅  沈荣芳 《灾害学》1997,12(4):24-28
对上海当前防灾救灾系统管理中存在的问题进行了分析,并且提出了相应的对策,对上海及其它城市的防灾救灾系统管理体系的改进与完善有一定的借鉴作用。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号