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181.
瑞典西海岸北部沿岸水域中的富营养化正在造成沿岸生态系统结构和功能的变化.为了在10~20年的过渡期内降低沿岸水域中营养物质,改善水质,按照欧洲水框架指令的要求,在措施计划中建议开展大规模的贻贝养殖.所有权、土地划拨、利益冲突及沿岸水体的保护正在阻挠着人们进入建立贻贝养殖场的合适水域.本文研究了关乎进入大规模贻贝养殖的沿岸水域这一领域的相关法律和法规中的障碍和可能性.在规划与建筑法、环境指令及与土地划拨和财产有关的法律框架中,给出了解决这个问题的一些可选择的方法并进行了讨论.适当地运用规划与建筑法,可以为进入沿岸水域进行以改善水的生态状况为目的的贻贝养殖提供有益的手段.  相似文献   
182.
Background, Aim and Scope Perfluorooctane sulfonate (PFOS; C8F17SO3-) is a fully fluorinated organic compound which has been manufactured for decades and was used widely in industrial and commercial products. The recent toxicological knowledge of PFOS mainly concerns mono-substance exposures of PFOS to biological systems, leaving the potential interactive effects of PFOS with other compounds as an area where understanding is significantly lacking. However, a recent study, reported the potential of PFOS to enhance the toxicity of two compounds by increasing cell membrane permeability. This is of particular concern since PFOS has been reported to be widely distributed in the environment where contaminants are known to occur in complex mixtures. In this study, PFOS was evaluated alone and in combination with cyclophosphamide (CPP) to investigate whether a presence of PFOS leads to an increased genotoxic potential of CPP towards hamster lung V79 cells. Genotoxicity was investigated using the micronucleus (MN) assay according to the recent draft ISO/DIS 21427-2 method. PFOS alone demonstrated no genotoxicity up to a concentration of 12.5 mg/L. However, PFOS combined with two different concentrations of CPP, with metabolic activation, caused a significant increase in the number of micronucleated cells compared to treatments with CPP only. These results provide a first indication that PFOS has the potential to enhance the genotoxic action of CPP towards V79 cells, suggesting that together with the alterations in cell membrane properties shown previously, that genotoxicity of complex mixtures may be increased significantly by changes in chemical uptake. Together with an earlier study performed by the own working group it can be concluded that PFOS alone is not genotoxic in this bioassay using V79 cells up to 12.5 mg/L, but that further investigations are needed to assess the potential interaction between PFOS and other substances, in particular regarding the impact of membrane alterations on the uptake of toxic substances. Materials and Methods: - Results: - Discussion: - Conclusions: - Recommendations and Perspectives: -  相似文献   
183.
Environmental Geochemistry and Health - The Riardo basin hosts groundwater exploited for the production of high quality, naturally sparkling, bottled water (e.g., Ferrarelle water), and circulating...  相似文献   
184.
Chemical investigation of the deepwater sponge Macandrewia azorica, collected from the flanks of the Gettysburg and Ormonde Sea Mount, North Atlantic, from a depth of 600 m, has led to the isolation of a new sterol with an unusual side chain (1), along with S-methylergothioneine (2). The structures of compounds 1 and 2 were established by employing spectroscopic techniques (NMR, MS, UV, IR and polarimetry). This is the first report of metabolites of a sponge belonging to the genus Macandrewia.  相似文献   
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Background

Nanotechnology is about discovering, developing and using materials consisting in their primary stage at a size within the low nanometer range. These ultrafine particles offer new properties and opportunities. Even if the synthesis of nanoparticles has been discovered not until during the last decades, the exposure of humans to ultrafine particles occurred long before, due to the generation of ultrafine particles in ambient air during combustion processing.

Aim

Within this review, only engineered nanoparticles are considered, because these technical products are associated with many hopes for new applications, while only little information is available about their potential adverse effects. At workpiaces, during manufacturing, in technical applications or in drugs, nanoparticles will always have ‘side effects’ which have carefully to be weighed against their advantages, before they can be released in the environment. Therefore, information about their safety and potential hazards is urgently needed.

Results and Discussion

Along with the technical development of nanoparticles, a public discussion has started, leading to extensive investigations on possible negative ‘side effects’ on human health. Research activities have been strengthened in departments for environmental toxicology, hygiene institutes and other academic facilities to identify hazard and risks during handling and use of these new materials. On the other hand, nanotechnology offers the promise to prematurely identify environmental problems through improved detection and monitoring capabilities, and significantly reduced environmental effects from cleaner manufacturing and synthesis approaches, which results in a reduction or elimination of wastes as well as reduced energy use, and unique remediation solutions as well as pollution strategies.

Conclusions

However, the potential impact of manufactured nanomaterials used in various applications also needs to be evaluated in the context of human health with regard to potential toxicology and routes of exposure, environmental effects, including fate, transport, transformation, bio-availability, and bio-accumulation, and an analysis of product-life cycle.  相似文献   
189.
The complexation behaviours of trivalent rare earth elements (La, Ce, Ho and Yb) by two types of humic acids were investigated under a specified set of conditions. Humic acids show quite different complexation capacities an conditional formation constants with the REEs. Apparently there are two types of binding sites in the functional groups of humic acid, in which the first binding sites have stronger ability than the second. Cerium shows the largest complexation capacities and highest formation constants among the four REEs with two humic acids, this anomaly may be relative to the distribution pattern of the REEs in seawater. The experimental results were comparable to the values of other metals reported and provided the basic data for the environmental geochemistry of rare earth elements.  相似文献   
190.
The measurement and induction of mixed function oxyigenases (MFOs) of limnetic gastropods were investigated to estimate their suitability as biomarkers. A determination of MFO activities was performed through the measurement of ethoxyresorufin-O-dealkylase (EROD), pentoxy-(PROD) and benzoxyresorufin-O-dealkylase-activity (BROD). Optimal measuring conditions of these activities were investigated in preparations of the digestive gland of 4 species of limnetic gastropods. Results indicate that MFO-activity inhibiting substances are accumulating in the microsomal pellet, the fraction commonly used for the measurement of MFO-activities. Therefore, the fraction used for induction studies was the postmitochondrial supernatant (PMS). EROD, PROD, and BROD activity ofPlanorbis planorbis andPlanorbis carinatus were measured after a treatment with Aroclor 1254 for 1–17 days. Maximal induction of EROD and PROD were 6 and 10 times the value in the control group ofP. carinatus, respectively induction inP. planorbis was lower. BROD-activity could not been measured inP. planorbis. InP. carinatus, BROD-activity increased to a maximum of 2 times after traetment with Aroclor 1254. The level of induction of EROD-activity is comparable to results described in analog studies with fish.  相似文献   
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