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571.
Environmental Science and Pollution Research - Spatio-temporal evolution of post-seismic landslides and debris flows provides a new perspective to understand post-earthquake evolution of geological...  相似文献   
572.
Environmental Science and Pollution Research - An increasing number of studies investigated the association between air pollution during pregnancy and the risk of eczema in offspring. However, no...  相似文献   
573.
基于博弈论的地铁车站恐怖袭击风险定量研究   总被引:3,自引:0,他引:3  
近年来发生的几起地铁重大恐怖袭击事件引起了各国政府、媒体和公众的广泛关注.地铁车站恐怖袭击可以看作博弈双方即袭击者和防御者之间的零和博弈.本文以某地铁线路上的22个车站为例,应用目标损失概率模型定量分析了恐怖袭击风险,通过防御资源变化得到了不同的目标损失概率.研究结果可以为地铁车站防御资源优化配置、防恐反恐预案编制等提供量化依据.  相似文献   
574.
茅坪河流域非点源污染负荷模拟   总被引:13,自引:1,他引:12  
许其功  刘鸿亮  沈珍瑶  冒亚明 《环境科学》2006,27(11):2176-2181
为定量化研究茅坪河流域农业非点源营养物质氮、磷的输出负荷,在茅坪河的亚流域陈家冲,利用2004-05~2004-10降雨期的监测数据,通过实测值和模拟值的比较对非点源污染模型SWAT(Soil and Water Assessment Tool)进行了率定和验证,采用Nash-Sutcliffe系数(R2)、均方根差(RMSE)和相对误差(CV)检验实测值和模拟值的拟合度.利用验证后的模型模拟了茅坪河流域营养物质氮、磷的输出负荷量.经验证径流、总氮和总磷的Nash-Sutcliffe系数分别为0.71、0.51和0.62,最小相对误差分别为1.8%、1.1%和10%,模型对氮和磷的输出模拟效果稍差,但对径流的模拟取得了较好的效果,表明该模型可运用于茅坪河流域非点源污染的模拟研究.模拟结果显示,2004-05~2004-10,茅坪河流域共有102.5 t氮和9.46 t磷流入长江,大量农业非点源污染的产生是造成茅坪河水质恶化的重要原因之一.  相似文献   
575.
A study was conducted to determine the adsorption/desorption of butachlor, myclobutanil and chlorpyrifos on five soils using a batch equilibration technique and to study the relationship between bioavailability to Allolobophora caliginosa and the adsorption/desorption of these three pesticides. The results showed that the adsorption/desorption processes of the tested compounds were mainly controlled by soil organic matter content (OM) and octanol/water-partitioning coefficient (K(ow)), and that the bioavailability of the pesticides was dependent on characteristics of pesticides, properties of soils, and uptake routes of earthworms. Bioconcentration of butachlor and myclobutanil was negatively correlated with Freundlich adsorption constant K(af) and K(df). However, only a slightly positive correlation between bioconcentration and K(af) and K(df) was observed for chlorpyrifos due to its high affinity onto soil.  相似文献   
576.
Liu Y  Qin X  Guo H  Zhou F  Wang J  Lv X  Mao G 《Environmental management》2007,40(6):966-980
Lake areas in urban fringes are under increasing urbanization pressure. Consequently, the conflict between rapid urban development and the maintenance of water bodies in such areas urgently needs to be addressed. An inexact chance-constrained linear programming (ICCLP) model for optimal land-use management of lake areas in urban fringes was developed. The ICCLP model was based on land-use suitability assessment and land evaluation. The maximum net economic benefit (NEB) was selected as the objective of land-use allocation. The total environmental capacity (TEC) of water systems and the public financial investment (PFI) at different probability levels were considered key constraints. Other constraints included in the model were land-use suitability, governmental requirements on the ratios of various land-use types, and technical constraints. A case study implementing the system was performed for the lake area of Hanyang at the urban fringe of Wuhan, central China, based on our previous study on land-use suitability assessment. The Hanyang lake area is under significant urbanization pressure. A 15-year optimal model for land-use allocation is proposed during 2006 to 2020 to better protect the water system and to gain the maximum benefits of development. Sixteen constraints were set for the optimal model. The model results indicated that NEB was between $1.48 × 109 and $8.76 × 109 or between $3.98 × 109 and $16.7 × 109, depending on the different urban-expansion patterns and land demands. The changes in total developed area and the land-use structure were analyzed under different probabilities (q i ) of TEC. Changes in q i resulted in different urban expansion patterns and demands on land, which were the direct result of the constraints imposed by TEC and PFI. The ICCLP model might help local authorities better understand and address complex land-use systems and develop optimal land-use management strategies that better balance urban expansion and grassland conservation.  相似文献   
577.
In this study,the effects of soluble readily biodegradable COD (sCOD) and particulate slowly biodegradable COD (pCOD) on anammox process were investigated.The results of the longterm experiment indicated that a low sCOD/N ratio of 0.5 could accelerate the anammox and denitrification activity,to reach as high as 84.9%±2.8% TN removal efficiency.Partial denitrification-anammox (PDN/anammox) and denitrification were proposed as the major pathways for nitrogen removal,accounting for 91.3% and 8.7% o...  相似文献   
578.
介绍了矿石破碎安全生产中的主体设备——液压圆锥破碎机的计算机控制,对系统的组成、功能、软件编制作了简述,构成的系统在矿山极具通用性。  相似文献   
579.
Urban Agglomeration is an inevitable outcome of urbanization and industrialization, and a main form of urban development. Based on the analysis of urbanization and urban system situation, this paper will discuss the integration of urban agglomeration development, using the urban area of Cheng (Chengdu)-Yu (Chongqing) Urban agglomeration (CYUA) as a case study. By means of industries, population and spatial integrations, the function, strength and competition of CYUA will be improved and this urban agglomeration will transit from a budding state to a growing and mature one in future. The sustainable development of CYUA will depend on countermeasures, such as accelerating industrialization and urbanization, building a traffic network and express roads, strengthening the ability of self-sufficiency, enlarging the ecological construction and environmental protection, and establishing the synergetic institution of cross districts.  相似文献   
580.
炼油厂碱渣处理工艺最佳技术路线选择   总被引:3,自引:0,他引:3  
在认真分析、讨论和比较各种碱渣处理方法的基础上,结合炼厂实际并考虑未来的发展需要,提出易地重建的碱渣处理装置宜采用回收粗酚、环烷酸并配套WAO氧化脱臭和SBR生物处理工艺的建议。  相似文献   
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