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361.
本文以淮南市为例,从产业结构、能源生产与消费、碳排放状况等方面,阐述淮南市低碳转型的背景状况,分析低碳转型发展的必要性、重点领域和发展方向、关键技术和方法、低碳城市的基础设施建设等,并讨论了淮南市低碳转型发展的保障措施。  相似文献   
362.
高含水率有机垃圾资源化处置对策   总被引:15,自引:0,他引:15  
耿土锁 《环境科技》2002,15(2):24-25
高含水率有机垃圾主要为城镇菜场垃圾、餐馆饮食业垃圾、家庭厨房垃圾和果品市场的瓜果皮等食物类垃圾,具有含水率高、易腐烂、营养元素丰富、有害物质少等特征,既易于专业收集,又易于厌氧发酵处理,可全部实现无害化和创造经济效果。应重视收集处理和综合利用高含水率有机垃圾的专门技术,减少垃圾填埋的数量、节省占地和保护环境。  相似文献   
363.
介绍了一套适合沿海丘陵地形条件的区域大气环境质量预测体系,它主要由局地扩散模式(HPDM模式,Misra模式)、中尺度气象场模式和区域扩散模式(分段烟流模式)组成,该系统具有较快的计算速度。同时文章对气象场模式中所采用的三维准静力动力学模型在地形追随坐标下的形式进行了较完整的描述,对变换后湍流扩散项的近似取舍进行讨论并且对传统的分段烟流模式的分段烟流作了连续性定义的改进。  相似文献   
364.
有关化工石化建设项目环境风险评价技术评估的探讨   总被引:8,自引:0,他引:8  
根据国家化工石化行业建设项目加强环境风险评价的主要规定,结合化工石化行业建设项目特点及环境影响技术评估,反思化工石化项目评价及评估工作,重点从环境风险评价方面,对进一步完善环境风险评价与防范的后评估,从严建设项目技术评估与环境管理等进行了初步探讨,目的是为建设项目环境影响技术评估和环境管理提供参考。  相似文献   
365.
湿式消解法对冷原子吸收测定生物样品中汞产生的干扰   总被引:3,自引:0,他引:3  
用不同的湿式消解法对多种生物样品的进行消解测定,分析了实验的干扰因素,并推荐了比较适宜的消解方法。  相似文献   
366.
The identification of contamination “hotspots” are an important indicator of the degree of contamination in localized areas, which can contribute towards the re-sampling and remedial strategies used in the seriously contaminated areas. Accordingly, 114 surface samples, collected from an industrially contaminated site in northern China, were assessed for 16 polycyclic aromatic hydrocarbons (PAHs) and were analyzed using multivariate statistical and spatial autocorrelation techniques. The results showed that the PCA leads to a reduction in the initial dimension of the dataset to two components, dominated by Chr, Bbf&Bkf, Inp, Daa, Bgp, and Nap were good representations of the 16 original PAHs; Global Moran’s I statistics indicated that the significant autocorrelations were detected and the autocorrelation distances of six indicator PAHs were 750, 850, 1,200, 850, 750, and 1,200 m, respectively; there were visible high–high values (hotspots) clustered in the mid-bottom part of the site through the Local Moran’s I index analysis. Hotspot identification and spatial distribution results can play a key role in contaminated site investigation and management.  相似文献   
367.
The purpose of this research is to establish an environmental management zoning for coal mining industry which is served as a basis for making environmental management policies. Based on the specific impacts of coal mining and regional characteristics of environment and resources, the ecological impact, water resources impact, and arable land impact are chose as the zoning indexes to construct the index system. The ecological sensitivity is graded into three levels of low, medium, and high according to analytical hierarchy processes and gray fixed weight clustering analysis, and the water resources sensitivity is divided into five levels of lower, low, medium, high, and higher according to the weighted sum of sub-indexes, while only the arable land sensitive zone was extracted on the basis of the ratio of arable land to the county or city. By combining the ecological sensitivity zoning and the water resources sensitive zoning and then overlapping the arable-sensitive areas, the mainland China is classified into six types of environmental management zones for coal mining except to the forbidden exploitation areas.  相似文献   
368.
Due to its prolific growth, oilseed rape (Brassica napus L.) can be grown successfully for phytoremediation of cadmium (Cd)-contaminated soils. Nowadays, use of plant growth regulators against heavy metals stress is one of the major objectives of researchers. The present study evaluates the ameliorate effects of 5-aminolevulinic acid (ALA, 0, 0.4, 2, and 10 mg/l) on the growth of oilseed rape (B. napus L. cv. ZS 758) seedlings under Cd stress (0, 100, and 500 μM). Results have shown that Cd stress hampered the seedling growth by decreasing the radical and hypocotyls length, shoot and root biomass, chlorophyll content, and antioxidants enzymes. On the other hand, Cd stress increased the level of malondialdehyde (MDA) and production of H2O2 and accumulation of Cd in the shoots. The microscopic study of leaf mesophyll cells showed that toxicity of Cd totally destroyed the whole cell structure, and accumulation of Cd also appeared in micrographs. Application of ALA at lower dosage (2 mg/l) enhanced the seedling growth and biomass. The results showed that 2 mg/l ALA significantly improved chlorophyll content under Cd stress and decreased the level of Cd contents in shoots. Application of ALA reduced the MDA and H2O2 levels in the cotyledons. The antioxidants enzymes (ascorbate peroxidase, peroxidase, catalase, glutathione reductase, and superoxide dismutase) enhanced their activities significantly with the application of 2 mg/l ALA under Cd stress. This study also indicated that higher dosage of ALA (10 mg/l) imposed the negative effect on the growth of oilseed rape. Microscopic study showed that application of ALA alleviated the toxic effects of Cd in the mesophyll cell and improved the cell structure. Use of 2 mg/l ALA under 500 μM Cd was found to be more effective, and under this dosage, cell structure was clear, with obvious cell wall and cell membrane as well as a big nucleus, which was found with well-developed two or more nucleoli. Chloroplast was almost round in shape and contained thylakoids membranes and grana, but starch grains were not found in chloroplast comparatively to other treatments. On the basis of our results, we can conclude that ALA has a promotive effect which could improve plant survival under Cd stress.  相似文献   
369.
In this study, the occurrence and sources of five cataloged antibiotics and metabolites were studied in Jiulongjiang River basin, south China. Nineteen antibiotics and 13 metabolites were detected in water samples from 16 river sampling sites, wastewater from 5 swine-raising facilities, and effluent from 5 wastewater treatment plants (WWTPs). The results showed that 12 antibiotics and 6 metabolites were detected in river water samples. Sulfonamides (SAs) and their metabolites were detected at high concentrations (8.59–158.94 ng/L). Tetracyclines (TCs) and their metabolites were frequently detected in swine wastewater, and the maximum concentration was up to the level in milligram per liter. Macrolides (MLs) and β-lactams (β-Ls) were found in all WWTP effluent samples and some river samples, while they were never found in any of the swine wastewater samples. SAs and quinolones (QNs) were detected in all samples. Hierarchical cluster analysis of 16 surface water samples was applied to achieve the spatial distribution characteristics of antibiotics in the Jiulongjiang River. As a result, two categories were obviously obtained. Principal component analysis and redundancy analysis showed that TCs and SAs as well as their metabolites were the major antibiotics in Jiulongjiang River, and they mainly originated from swine wastewater, while the QNs, MLs, and β-Ls in the Jiulongjiang River came from WWTP effluent.  相似文献   
370.
Cyanobacterial blooms have received increasing attention as a public biohazard for human and animal health. To assess the effect of cyanobacteria-dominant lake water on juvenile fish, we measured the responses of specific growth rate, condition factor, body weight and body length, oxidative stress, and related gene expression of juvenile bighead carp Hypophthalmichthys nobilis exposed to in situ eutrophic lake (Chl a was around 7.0 μg L−1). Results showed in situ cyanobacteria-dominant lake water had no effect on the growth performance, but significantly elevated the contents of malondialdehyde, the expression of heat shock protein 70, and the activity of superoxide dismutase, indicating that oxidative stress occurred. Meanwhile in situ lake water significantly decreased the expression of catalase and glutathione S-transferase genes. We conclude that in situ cyanobacteria-dominated lake water was harmful to juvenile bighead carp based on the oxidative stress and changes in the related gene expression levels.  相似文献   
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