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71.
空气质量指数计算方法是目前全国各城市空气质量重要信息发布的基础,广泛应用于城市空气自动监测的空气质量评价。依据《HJ 633-2012环境空气质量指数(AQI)技术规定(试行)》发布环境空气质量指数(AQI)计算方法,利用VBA在Excel下编写宏程序,可以轻松实现空气质量日报信息的发布,使用户从手工重复性的填充和插入函数操作方式中彻底解放出来。  相似文献   
72.
本文运用目前较为流行的三种仿真工具来对电动汽车辐射源进行仿真分析,运用MATLAB的simulink模块对汽车电池模型等效电路进行模型的搭建与仿真分析电路电流,得到电流的表达式和仿真图,再根据对电流图形进行曲线拟合,得到电流的近似表达式。把表达式当作是时间的函数,这样就可以将电池工作时的电流导入到CST中并作为激励源进行空间的仿真分析,得到电磁波的分布图。  相似文献   
73.
The article presents proposals for an indexical evaluation of exposure of hand tool operators to vibrations. The presented indices have been developed on the basis of the results of laboratory tests. The examinations studied the effect of pressure force and grip force exerted by an operator on a hand tool as well as the amplitudes and frequencies of an exciting signal on vibrations transmitted in the hand-tool handle system.  相似文献   
74.
A support tool system comprising risk and priority analyses was illustrated in a geographical information system environment and also tested with data from two forest protection areas for comparison of the system output. The system is recommended as a management monitoring tool for areas where village forest protection at a local level is taking place. The geographical area in the eastern part of India is subject to scarcity of forest resources and is representative in the context of widespread occurrence of local forest protection. Data used were topography, hectares protected, population census, distance to forest and other villages, degree of forest regeneration, presence of plantations, age of protection, surrounding forest resources, and population mix. Methods used were digitizing information for the systems' different layers, analyses of satellite information, field work, gathering of local information, and the application of five risk/priority analyses: erosion, ecological and institutional sustainability, conflict, and degree of dependency. Questions asked were how the different analyses should be interpreted and how the system could be kept updated. The results show that the system needs resource-demanding and field assistance to be kept dynamic. The system is also dependent on the interpretations of the analyses. The limits or levels of assistance for forest management depend on the resources available. The system illustrates how a tool can be utilized for decisions regarding input of resources. It can further be very useful in defining and comparing different areas in order to detect areas in need of assistance and the type of help needed.  相似文献   
75.
低温低浓度下城市污水活性污泥自然培养和驯化   总被引:1,自引:0,他引:1  
介绍了交互式物化/生化反应器处理城市污水的工艺流程和特点。研究了交互式物化/生化反应器中试系统在低温低进水浓度(水温13℃~17℃,平均CODcr为144mg/L)和自然不接种的情况下,利用生态絮凝剂聚硅硫酸铁和助凝剂聚丙烯酸进行活性污泥培养和成长的过程规律,并在自然状态下(水温17℃~23℃,平均CODcr为117mg/L)对生成的活性污泥进行驯化。  相似文献   
76.
Thom.  FH 孙昭民 《灾害学》1994,9(3):91-94
本文系统分析和总结了美国在洪泛平原管理中的经验教训,研究了减灾措施、行为反应及国家长期减灾目标等方面的内容,从综合的角度提出了统一的国家减灾计划。  相似文献   
77.
排污权影子价格模型的分析及启示   总被引:3,自引:0,他引:3  
通过建立排污权交易市场,引入市场机制力促进企业污染减排,以形成治污的长效机制,是推进节能减排制度创新的重要举措。作为一种以市场为基础的环境经济政策,排污权交易体系具有污染治理的成本效率特征,允许企业在以最低成本减少污染的同时拥有一定灵活性。在中国当前的排污权交易试点工作中,排污权初始分配方式成为了各方争论的一个焦点。利用排污权影子价格模型,深入剖析了排污权影子价格的形成机制和相关命题,并论述了排污权影子价格的政策含义及其对中国开展排污权交易的启示。  相似文献   
78.
自然资源核算的生态足迹模型演进及其评论   总被引:2,自引:0,他引:2  
生态足迹模型作为从生态角度对自然资源进行核算的方法,其发展经历了从一维模型向二维模型,并从二维模型向三维模型的演进过程,论文从科学问题、模型内涵、应用指向和解释能力等4个方面对生态足迹模型演进作了梳理和评论。研究结果表明:1)生态足迹模型是自然资源核算的一个生物物理性工具,弥补了主流的国民经济核算体系下自然资源价值核算的不足。2)一维模型开创性地引入生态生产性土地概念开展自然资源消费核算,以此来测算人类活动对生态的占用情况;二维模型在自然资源消费核算维度的基础上,引入自然资源生态承载能力维度,开拓了自然资源承载力评价的新视野;三维模型进一步从流量和存量两个维度理解自然资源生态承载能力,以圆柱体体积表达生态足迹,生动刻画人类活动对所处区域的生态压力。3)一维模型是二维、三维模型的基础,但它们解决的科学问题各有不同,从而所适用的研究尺度、应用指向也有所差异。4)生态足迹模型属于静态分析模型,无法解释生态经济社会系统的动态变化情况;二维和三维模型属于封闭模型,其计算结果不能准确反映区域生态的真实状况。最后,探讨了生态足迹模型进一步优化的方向。  相似文献   
79.
Implementing agricultural best management practices (BMPs) is influenced by a balance of desired environmental outcomes, economic feasibility, and stakeholder familiarity, the latter taken to be related to BMP acceptability. To explore this balance, we developed a multi‐objective decision support system for allocating BMP type and placement by coupling the Soil and Water Assessment Tool with a nondominated sorted genetic algorithm that minimizes total phosphorus (TP) yields from agricultural hydrologic response units (HRUs) and costs, while using stakeholder BMP familiarity as a constraint; conventional tillage, no tillage, nutrient management, riparian buffers, and contour cropping were explored. Using constraints representing current conditions, the optimization resulted in 59.6 to 81.0% reduction in agricultural TP yield from HRUs at costs ranging between US $0.8 and US $5.3 million. The constrained optimization tended to select mostly single BMPs or at most two BMPs for a given HRU due to these BMPs having higher acceptability to stakeholders. In contrast, the unconstrained case, representing full familiarity, selected 2‐ and 3‐BMP applications. There was little difference in costs between the constrained and unconstrained cases below an 80% TP yield reduction; however, significant differences were found at larger reductions, supporting the value of stakeholder education and extension efforts. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.  相似文献   
80.
McIntyre JJ  Venette S 《Disasters》2006,30(3):351-363
This paper examines the dependability of the Event Assessment Tool over time. The latter is part of a CD-ROM--Emergency Risk Communication CDCynergy--distributed primarily to public information officers in the United States by the Centers for Disease Control and Prevention. The Event Assessment Tool is designed to aid emergency professionals in identifying the magnitude of a crisis event and to suggest appropriate actions to confront such a situation. Applied twice during the 2001 anthrax bioterrorism crisis in Boca Raton, Florida, the tool functioned in a binary manner by first indicating a moderate crisis level (on 4 October) and then four days later (on 8 October) a highly intense crisis, suggesting that it is time sensitive. This anthrax event provides an opportunity for crisis and disaster managers to understand the dynamic nature of crises. Rapid changes during these types of events suggest that any metric used to predict intensity must account for this variability. Additional limitations and implications of the tool are discussed.  相似文献   
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