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71.
Indoor air quality in university environments   总被引:1,自引:0,他引:1  
This study evaluates the airborne microflora in research laboratories of the University of Chieti (Italy). A quali-quantitative evaluation of the index microbial air contamination was performed using the settle plate method. The microbial air contamination was evaluated during 6 months in three university buildings (A, B, and C). Nutrient agar plates were exposed, monthly, for 1 h at the morning and the afternoon to evaluate the colony forming units per plate per hour. Together with the quantitative analysis, the most frequent bacterial and fungal colonies isolated were also characterized. Moreover, in each sampling, the number of the occupants in each room was recorded to evaluate a possible relationship with the microbial pollution. The microbial concentration was always within the limit values defined for these environments. Buildings A and C displayed a seasonal fluctuation of airborne microflora with the increase in microbial concentration in the warmer season (April to June) in respect to the colder period (October to December). The most common microorganisms detected in the indoor air of the examined buildings were Gram-positive bacteria, belonged to the genera Staphylococcus, Bacillus, and Actinomyces. Data presented here underline the useful monitoring of the research university laboratories also emphasizing the effectiveness of the settle plate method.  相似文献   
72.
To evaluate exposure to benzene in urban and rural areas, an investigation into personal exposure to benzene in traffic policemen, police drivers and rural (roadmen) male outdoor workers was carried out. Personal samples and data acquired using fixed monitoring stations located in different areas of the city were used to measure personal exposure to benzene in 62 non-smoker traffic policemen, 22 police drivers and 57 roadmen. Blood benzene, urinary trans-trans muconic acid (t,t-MA) and S-phenyl-mercapturic acid (S-PMA) were measured at the end of work shift in 62 non-smoker traffic policemen, 22 police drivers and 57 roadmen and 34 smoker traffic policemen, 21 police drivers and 53 roadmen. Exposure to benzene was similar among non-smoker traffic policemen and police drivers and higher among non-smoker urban workers compared to rural workers. Blood benzene, t,t-MA and S-PMA were similar among non-smoker traffic policemen and police drivers; blood benzene and t,t-MA were significantly higher in non-smoker urban workers compared to rural workers. Significant increases in t,t-MA were found in smokers vs. non-smokers. In non-smoker urban workers airborne benzene and blood benzene, and t,t-MA and S-PMA were significantly correlated. This study gives an evaluation of the exposure to benzene in an urban area, comparing people working in the street or in cars, to people working in a rural area. Benzene is a certain carcinogen for humans. The results we showed should lead to more in-depth studies about the effects on health of these categories of workers.  相似文献   
73.
采用隔声窗作为典型道路的交通噪声控制措施,探索隔声性能的现场监测方法。分别选取真空玻璃窗与中空玻璃窗进行监测,两种隔声窗对交通噪声1000 Hz 和2000 Hz 两个倍频带的隔声量最大,真空玻璃隔声窗对500 Hz 倍频带及以下的噪声比中空玻璃隔声窗更有效,如果采用两种隔声窗进行组合,在全频带的隔声量达到25 dB。  相似文献   
74.
Lichens collected in an unpolluted forest (background) in November 2004, transplanted at 41 sampling sites along the Madina-Tetteh Quarshie road, retrieved in February 2005 and analysed were found to contain higher concentrations of Manganese (Mn), Vanadium (V), lead, Cadmium (Cd), Chromium (Cr) and Nickel (Ni) than in the background area. Observations showed that of all the heavy metals studied, Manganese concentrations were highest at all sampling points with maximum values around a traffic light, an intersection and car fitting/mechanic workshops. Significant correlations were found between Ni and Mn, Mn and Cr and Mn and V. Statistical analysis also revealed a relatively even dispersion of the studied elements on the eastern side of the road than on the western side.  相似文献   
75.
University of Brescia and Mahidol University of Bangkok developed a project in Phang Nga province (Thailand), the most damaged by 2004 tsunami. In particular, the study, performed between April and May 2006, dealt with the surface and ground water monitoring in Ban Nam Khem village and the experimental evaluation of possible drinking treatment alternatives. The monitoring highlighted that saline content in the tsunami affected area is decreasing but still very high (conductivity presented values up to 2,600 and 6,230 microS/cm in ground and surface water, respectively); hence, advanced and complicated processes such as reverse osmosis should be adopted to treat such water for drinking purposes. Waiting for ground water salinity to assume acceptable values, activities for the reduction of its organic and microbiological contamination will be started. However, it has to be underlined that the diffusion of drinking water to a greater part of population can be obtained only through the realization of new centralised treatment plants and the improvement of existing ones (serving at the moment about 20% of inhabitants).  相似文献   
76.
贵州省部分地区土壤中酞酸酯类污染现状调查   总被引:5,自引:1,他引:4  
对贵州省部分地区表层土壤中酞酸酯类的污染状况进行了调查。分别在遵义地区、黔南地区、黔东南地区和毕节地区采集483个土壤样品分析,结果表明,样品中酞酸酯总质量比(ΣPAEs)为未检出~8.22 mg/kg,均值为0.63 mg/kg。其中DEHP和DBP为主要污染物,均值分别为0.32 mg/kg和0.24 mg/kg,检出率分别为90.89%和97.10%。  相似文献   
77.
Our study was carried out on two species of clams, Venerupis aurea laeta and Cerastoderma edule glaucum, from Ganzirri Lake considered as “environmental biomarkers” for their changes in physiology, morphology or distribution under the influence of substances in the environment. The aim of the present study was to conduct a statistical analysis on Venerupis and Cerastoderma to investigate the difference between the two autochthonous clams according to the presence of metals, and to link metal concentrations to the reproductive cycle of clam during 2009–2010. Metal analysis was carried out with inductively coupled plasma mass spectrometry (ICP-MS). Accuracy and precision were assessed by analyzing the certified standard matrix: mussel tissue NIST SRM 2976. The multivariate analysis was made using the SPSS 13.0 software package for Windows (SPSS Inc., Chicago, IL). In this study, the concentrations of some metals found in clam tissues showed seasonal cycles with higher values in summer than in winter. The significances of metal concentrations differences between Venerupis and Cerastoderma samples were estimated with Mann–Whitney U-test. The concentrations of Ag, As, Cd, Mn, Se and Zn show a significant p-level that suggests a difference between the two group samples. Statistical analysis showed that the link of metal concentrations to the reproductive cycles of Venerupis and Cerastoderma was not evident.  相似文献   
78.
基于环境卫星CCD数据的黄海浒苔遥感监测   总被引:1,自引:1,他引:0  
2007年以来,黄海海域每年夏季都发生大面积浒苔绿藻潮,影响沿岸人民的生活、生产。考虑到其分布范围动则几千、上万平方公里,水面监测很难实施,尝试利用遥感技术对其分布和发展变化情况进行监测。基于中国自主产权的环境卫星(HJ1)数据,采用经典植被指数算法和人工辅助判读方法,对2013年黄海浒苔暴发全过程进行了连续遥感监测,分析了此次浒苔过程的分布和漂移路线。监测结果表明,浒苔绿藻潮首发于江苏盐城东部海域,由南向北逐渐漂移,面积逐渐扩大,结束于青岛东北部海域;该期间,浒苔最大覆盖面积达663.54平方公里。  相似文献   
79.
Sustainable urban development focuses on enhancing urban well-being, while also balancing the demands of urban social and economic development, natural resource consumption, and environmental pollution. This work used general data envelopment analysis to assess the urban sustainability efficiency (USE) and sustainability potential (SP) in Lanzhou and Xiamen, two cities that are characteristic of urban areas in western and eastern China. The assessment indicator system included important natural and urban welfare factors as input and output indices, respectively. The results showed that overall urban sustainability efficiency increased in Lanzhou and Xiamen from 1985 to 2010, but that the sustainability of natural resources clearly decreased. The urban sustainability efficiency of Xiamen was higher than that of Lanzhou, and the sustainability potential of Xiamen was lower than that of Lanzhou; this indicates that Xiamen performed better in terms of urban sustainable development. The urban sustainability efficiency in Xiamen has increased with increasing urban population, and the rate and scale of economic development have been higher than in Lanzhou. The assessment and analysis performed in this study show that cities with different natural resources and development characteristics have different forms, patterns, and trajectories of sustainable development.  相似文献   
80.
气象因子对臭氧的影响及其在空气质量预报中的应用   总被引:1,自引:0,他引:1  
为提高重庆市臭氧(O_3)预报准确率,利用2013—2015年5—10月O_3监测数据和气象数据,通过主成分分析、逐步回归分析等方法,确定了影响重庆O_3浓度的主要气象因素为最高温度、温差、太阳辐射、降水量、相对湿度、水气压和压差;通过基于O_3污染水平相似的主要气象控制因子筛选和最优组合的预报结果优化方法,提高了O_3预报准确率,使2016年5—8月O_3的AQI类别预报准确率由57.7%增至72.4%,O_3超标的预报准确率由38%增至46%。  相似文献   
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