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131.
A new, direct method was developed for quantifying inorganic particulate aerosols trapped by the forest canopy, and for determining the resulting input of elements to a forest ecosystem. The method is based on direct measurements of only six parameters. Using this method, it is possible to determine the load of aerosols trapped by the forest canopy and deposited to leaves, as well as the load of aerosols falling to the forest floor by impaction on plants. It is also possible to estimate the aerosol input of soluble and insoluble elements to an ecosystem. With this new method it has been found that the load of aerosols trapped by the canopy of a mixed forest located in the Rybnik Coal Basin averaged 189.0 kg x ha-1 x growing season-1, or 39.3% of the total inorganic particles reaching the ecosystem. The trapped aerosols provided 13.4 kg x ha-1 of soluble nitrogen and 0.91 kg x ha-1 of insoluble nitrogen over the growing season. At the same time, the input of soluble nitrogen from the atmosphere with rainfall to an open area averaged 13.9 kg x ha-1, and the input of insoluble nitrogen with inorganic dusts averaged 1.4 kg x ha-1.  相似文献   
132.
在自然林火不再发生的同时,人们为了促进针叶树木的生长清除了落叶树种,并人为地将丰饶的森林变成了农地,由此,欧洲北部原有的针叶林景观发生了很大变化,一些地区的落叶林成分大大减少.然而,在乡村中落叶树种和落叶林得以保存下来,在一些弃耕的农田中也通过自然更新产生了新的落叶林木.我们在研究中做出以下假设,不同地区落叶林目前的分布格局与乡村中农业区和非农业区的分布相关,这种分布的形成又与当地的自然条件和以土地利用变化的形式表现的近期经济发展密切相关.我们的研究对象包括了瑞典北方针叶林和半北方针叶林区域中的6个地点--北博滕(Norrbotten)、翁厄曼兰(Angermanland)、耶姆特兰(Jamtland)、达拉纳(Dalarna)、Bergslagen和斯莫兰(Smaland),分析了乡村内农业区和非农业区中落叶林的空间分布.在每个地区,选择了6个以乡村为中心的5×5km样带.研究结果表明,在不同地区乡村中的不同景观区域,落叶林的分布和组成存在着明显差异.从单个乡村来看,翁厄曼兰中DEC(即落叶林成分)所占的比例平均最高(17%),而耶姆特兰则最低(2%).然而,农业区内和非农业区内DEC的数量却存在着规律性的地区差异,DEC在南方农业区内(斯莫兰)所占的比例最高,北方通常很低.对比之下,非农业区内DEC的数量在北方最高.相对较多的DEC出现在农业大量减少的地区的森林边缘地带(翁厄曼兰、达拉纳、Bergslagen).由于乡村在与落叶林有关的生物多样性中有着重要作用,因此本项研究的结果表明了对整个景观中的落叶林进行综合管理的必要性.通过本项研究,我们还可以看到卫星遥感数据可用于分析景观尺度上落叶树木和林分的空间分布.为了进行更为深入的研究,我们需要改进的专题分辨率以区分落叶林具相关生物特性意义的林分质量.  相似文献   
133.
Environmental Science and Pollution Research - The adverse effects of air pollution on the cardiovascular system have been well documented. Nonalcoholic fatty liver disease (NAFLD) is an...  相似文献   
134.
Environmental Science and Pollution Research - The concepts of the cities we know nowadays, and which we are accustomed to, change at a very rapid pace. The philosophy of their design is also...  相似文献   
135.
Russian Journal of Ecology - Winter quantitative studies on the Rook Corvus frugilegus, Hooded Crow Corvus cornix and Jackdaw Corvus monedula were conducted independently by two observers in the...  相似文献   
136.
Mine rescuers’ heat load under the same physical effort load (25% of the maximal oxygen uptake), using three types of breathing apparatus, in newly developed heat-removing underwear and outerwear was assessed for typical work conditions of mine rescuers, under milder and harsher ambient conditions of 32 and 38?°C, respectively, both at relative humidity of 85% and air velocity of 1.0?m/s. Expending physical effort at the same load while using different kinds of breathing apparatus resulted in a similar heat load. Under both milder and harsher ambient conditions, heat storage and sweating intensity were greater than the average limit value recommended by hygienic standards, which indicates that the use of breathing apparatus significantly hinders heat exchange with the environment. The developed clothing for mine rescuers was highly rated, and was considered by most people to be better than that used currently.  相似文献   
137.
It is well established that aquatic wildlife in marine and freshwater of the European Union is exposed to natural and synthetic endocrine disruptor compounds (EDCs) which are able to interfere with the hormonal system causing adverse effects on the intact physiology of organisms. The traditional wastewater treatment processes are inefficient on the removal of EDCs in low concentration. Moreover, not only the efficiency of treatment must be considered but also toxicological aspects. Taking into account all these aspects, the main goal of the study was to investigate the photochemical decomposition of hazardous phenolic compounds under simulated as well as natural sunlight from the toxicity point of view. The studies were focused on photodegradation of 2,4-dichlorophenol as well as mixture of phenol, 2-chlorophenol and 2,4-dichlorophenol. Photosensitized oxidation process was carried out in homogeneous and heterogeneous system. V. fischeri luminescence inhibition was used to determine the changes of toxicity in mixture during simulated and natural irradiation. The photodegradation was carried out in three kinds of water matrix; moreover, the influence of presence of inorganic matter on the treatment process was investigated. The experiments with natural sunlight proved applicability of photosensitive chitosan for visible-light water pollutant degradation. The results of toxicity investigation show that using photosensitive chitosan for visible-light, the toxicity of reaction mixture towards V. fischeri has significantly decreased. The EC50 was found to increase over the irradiation time; this increase was not proportional to the transformation of the parent compounds.  相似文献   
138.
Principal component analysis (PCA) was applied to a data set containing the levels of indicator polychlorinated biphenyls (PCBs) in human milk of mothers living in the Wielkopolska region, Poland, in order to investigate the information captured in the PCB patterns and to elucidate the relationship between PCB concentrations in milk and donor characteristics. According to the obtained PCA results milk fat content was the most influential factor affecting the PCB levels in milk of the Wielkopolska cohort. The lifestyle data collected from the questionnaire completed by the donors appeared to have no influence on PCB concentrations in breast milk. The score plots revealed the PCB contents of milk were quite low and uniform with a few outliers, without discrimination observed either between the primipareous and secundipareous females or between donors from the urban and rural areas. Comparison of the PCB levels and profiles of human milk from the Wielkopolska region and from various European and Asian locations made by PCA reflected a generally low background exposure and indicated the possible reasons for the outlying of some samples. In order to enhance the chances of observing the relationship between donor habits and PCB levels in breast milk it was suggested that the questionnaire be redesigned to gather information about vegetable product consumption and indoor air exposure.  相似文献   
139.
Activity concentrations, inventories and activity ratios of 137Cs, 238Pu, 239?+?240Pu and 241Am in soil profiles were surveyed in the dry tundra and the adjoining proglacial zones of glaciers at a High Arctic site on Svalbard. Vertical profiles of radionuclide activities were determined in up to 14-cm-thick soil sequences. Additionally, soil properties (pH, organic matter, texture, mineral composition and sorption capacity) were analyzed. Results obtained in this study revealed a large range of activity concentrations and inventories of the fallout radionuclides from the undetectable to the uncommonly high levels (inventories of 30,900?±?940, 47?±?6, 886?±?80 and 296?±?19 Bq/m2 for 137Cs, 238Pu, 239?+?240Pu and 241Am, respectively) found in two profiles from the proglacial zone. Concentration of these initially airborne radionuclides in the proglacial zone soils is related to their accumulation in cryoconites that have a large ability to concentrate trace metals. The cryoconites develop on the surface of glaciers, and the material they accumulate is deposited on land surface after the glaciers retreat. The radionuclide inventories in the tundra soils, which effectively retain radionuclides due to high organic matter contents, were comparable to the global fallout deposition for this region of the world. The 238Pu/239?+?240Pu activity ratios for tundra soils suggested global fallout as the dominant source of Pu. The 238Pu/239?+?240Pu and 239?+?240Pu/137Cs activity ratios in the proglacial soils pointed to possible contributions of these radionuclides from other, unidentified sources.  相似文献   
140.
Living or formerly living organisms are being used to obtain information on the quality of the general health status of our environment by bioindication and biomonitoring methods for many decades. Thus, different roads toward this common scientific goal were developed by a lot of different international research groups. Global cooperation in between various scientific teams throughout the world has produced common ideas, scientific definitions, and highly innovative results of this extremely attractive working field. The transdisciplinary approach of different and multifaceted scientific areas—starting from biology, analytical chemistry, via health physics, up to social and economic issues—have surpassed mental barriers of individual scientists, so that “production” of straightforward common results related to the influence of material and immaterial environmental factors to the well-being of organisms and human life has now reached the forefront of international thinking. For the further sustainable development of our common scientific “hobby” of bioindication and biomonitoring, highest personal energy has to be given by us, being teachers to our students and to convince strategically decision makers as politicians to invest (financially) into the development of education and research of this innovative technique. Young people have to be intensively convinced on the “meaning” of our scientific doing, e.g., by extended forms of education. One example of multilingual education of students on a global scale and perspective is given here, which we started about 3 years ago.  相似文献   
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