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A two-stage inexact joint-probabilistic programming (TIJP) method is developed for planning a regional air quality management system with multiple pollutants and multiple sources. The TIJP method incorporates the techniques of two-stage stochastic programming, joint-probabilistic constraint programming and interval mathematical programming, where uncertainties expressed as probability distributions and interval values can be addressed. Moreover, it can not only examine the risk of violating joint-probability constraints, but also account for economic penalties as corrective measures against any infeasibility. The developed TIJP method is applied to a case study of a regional air pollution control problem, where the air quality index (AQI) is introduced for evaluation of the integrated air quality management system associated with multiple pollutants. The joint-probability exists in the environmental constraints for AQI, such that individual probabilistic constraints for each pollutant can be efficiently incorporated within the TIJP model. The results indicate that useful solutions for air quality management practices have been generated; they can help decision makers to identify desired pollution abatement strategies with minimized system cost and maximized environmental efficiency.  相似文献   
453.
为了查明遵化市地质灾害分布规律和发生机制,通过野外实际调查和搜集相关资料等方法,对辖区内各种地质灾害进行了细致的分析和研究,阐述了产生地质灾害的地质条件和诱发因素,并对今后地质灾害的发展趋势做了可靠性的预测,对地质灾害防治提出建设性意见。遵化市地质灾害以地面塌陷和泥石流危害最大,其防治措施应以预防为主,加强监管力度,并积极做好工程防治工作。  相似文献   
454.
Irrigation with polluted water from the upper Yellow River (YR) channel of Northwest China has resulted in agricultural soil being contaminated by heavy metals (HMs). This causes major concerns due to the potential health risk to the residents in this area. The present study aims to assess the efficiency of constructed wetland (CW) in reducing the heavy metal contamination in irrigation water and food crops, thus in reduction of potential health risk to the residents. The associated risk was assessed using hazard quotient (HQ) and hazard index (HI). The results showed a potential health risk to inhabitants via consumption of wheat grain irrigated with untreated water from YR. However CW could greatly reduce the human health risk of HMs contamination to local residents through significantly decreasing the concentrations of HMs in wheat grain. In theory, the reduction rate of this risk reached 35.19% for different exposure populations. Therefore, CW can be used as a system to pre-treat irrigation water and protect the residents from the potential HMs toxicity.  相似文献   
455.
在我国中低抗震设防烈度地区的既有钢筋混凝土结构中,有很大一部分既有钢筋混凝土柱在地震作用下容易发生剪切破坏,失去竖向承载力,导致既有建筑发生倒塌,造成严重的经济损失和人员伤亡。一个简单、高效的滞回模型对剪切失效型既有钢筋混凝土柱的抗震性能评估具有重要意义。首先提出了一个简化的七参数折线型滞回模型,然后基于SERIES数据库中的剪切失效型钢筋混凝土柱试验结果,采用微分进化算法,对七参数折线型滞回模型进行了参数识别。最后,采用经验回归分析方法,提出了七参数折线型滞回模型中关键参数的经验预测方程。结果表明:给定设计参数,提出的七参数折线型滞回模型可以方便、快速地预测剪切失效型钢筋混凝土柱的恢复力-位移关系,便于工程应用。  相似文献   
456.
Environmental Science and Pollution Research - The accumulation of arsenic (As) in rice is one of the food security-related concerns in As-contaminated areas all over the world. Biochar, a...  相似文献   
457.
基于全国第七次(2004年-2009年)森林资源清样调查资料,并参考上海市2011年森林植被遥感数据,运用线性相关和双曲线相关的换算因子连续函数法,对上海8种主要乔木林分碳储量进行估算,并分析了不同龄组和地域分布的乔木林分碳储量。结果表明,两种方法的估值差别较大,但均是樟树、幼龄林和市区乔木林分碳储量贡献比较大。  相似文献   
458.
能源富集城市是指该市的能源储藏量丰富,能源工业的收入是该市的主要经济支柱。能源富集城市在享受能源开采利用带来巨大的收益同时,也在饱受着能源开采利用带来巨大的恶果。本文以庆阳市为例.首先分析了庆阳市发展过程中存在的问题,其次借鉴成功转型的能源城市案例,对庆阳市成功转型,走上可持续发展道路提出了相关的对策建议。  相似文献   
459.
本文从生物多样性维持与保护、土壤保持、水源涵养、防风固沙四方面进行包头市生态重要性评价,得出包头市生态重要性等级变化趋势,以期为划分包头市生态功能区划以及城市科学发展提供理论依据。  相似文献   
460.
Emission factors (EFs) of parent polycyclic aromatic hydrocarbons (pPAHs), nitrated PAHs (nPAHs), and oxygenated PAHs (oPAHs) were measured for indoor corn straw burned in a brick cooking stove under different burning conditions. The EFs of total 28 pPAHs, 6 nPAHs and 4 oPAHs were (7.9 ±3.4), (6.5 ±1.6)×10^-3, and (6.1 ±1.4)×10^-1mg/kg, respectively. Fuel charge size had insignificant influence on the pollutant emissions. Measured EFs increased significantly in a fast burning due to the oxygen deficient atmosphere formed in the stove chamber. In both restricted and enhanced air supply conditions, the EFs of pPAHs, nPAHs and oPAHs were significantly higher than those measured in normal burning conditions. Though EFs varied among different burning conditions, the composition profiles and calculated isomer ratios were similar, without significant differences. The results from the stepwise regression model showed that fuel burning rate, air supply amount, and modified combustion efficiency were the three most significant influencing factors, explaining 72%-85% of the total variations.  相似文献   
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