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361.
The paper industry is responsible for a considerable amount of greenhouse gas (GHG) emissions mainly due to its intensive energy requirements. The production of heat and power streams in a cogeneration system, i.e., a combined heat and power (CHP) plant, releases considerable amounts of GHG emissions into the atmosphere. Such emissions are already subjected to legislation globally. The amount of GHG emissions is usually calculated from the product of the total amount of energy activity multiplied by an emission factor. However, each energy output stream should get a share of emissions responsibility. This fact could assist in assigning weights to the emissions generated for power and thermal purposes in a combined heat and power plant. However, developing a suitable method of allocating emissions in a cogeneration system is still a concern and a subject research for scientists, companies and policy makers. This paper exposes and evaluates different published allocation methods and applies them to a real case of a combined heat and power plant integrated in a paper mill and proposes a new allocation method.  相似文献   
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Land use and land cover change (LUCC) is an acknowledged cause of the current biodiversity crisis, but the link between LUCC and biodiversity conservation remains largely unknown at the regional scale, especially due to the traditional lack of consistent biodiversity data. We provide a methodological approach for assessing this link through defining a set of major pressures on biodiversity from LUCC and evaluating their extent, distribution, and association with a set of physical factors. The study was performed in the Metropolitan Region of Barcelona (MRB, NE of Spain) between 1956 and 2000. We generated a LUCC map for the time period, which was reclassified into a set of pressures on biodiversity (forestation, deforestation, crop abandonment, and urbanization). We then explored the association of these pressures with a set of physical factors using redundancy analysis (RDA). Pressures encompassed 38.8 % of the MRB area. Urbanization and forestation were the dominating pressures, followed by crop abandonment and deforestation. RDA showed a significant distribution gradient of these pressures in relation to the studied physical factors: while forestation and deforestation are concentrated in remote mountain areas, urbanization mainly occurs in lowlands and especially on the coast, and close to previous urban centers and roads. Unchanged areas are concentrated in rainy and relatively remote mountain areas. Results also showed a dramatic loss of open habitats and of the traditional land use gradient, both featuring Mediterranean landscapes and extremely important for their biodiversity conservation. Implications of these results for biodiversity management are finally discussed.  相似文献   
367.
Estuarine areas represent complex and highly changing environments at the interface between freshwater and marine aquatic ecosystems. Therefore, the aquatic organisms living in estuaries have to face highly variable environmental conditions. The aim of this work was to study the influence of environmental changes from either natural or anthropogenic origins on the physiological responses of Mytilus edulis. Mussels were collected in the Vilaine estuary during early summer because this season represents a critical period of active reproduction in mussels and of increased anthropogenic inputs from agricultural and boating activities into the estuary. The physiological status of the mussel M. edulis was evaluated through measurements of a suite of biomarkers related to: oxidative stress (catalase, malondialdehyde), detoxication (benzopyrene hydroxylase, carboxylesterase), neurotoxicity (acetylcholinesterase), reproductive cycle (vitelline, condition index, maturation stages), immunotoxicity (hemocyte concentration, granulocyte percentage, phagocytosis, reactive oxygen species production, oxidative burst), and general physiological stress (lysosomal stability). A selection of relevant organic contaminant (pesticides, (polycyclic aromatic hydrocarbons, polychlorobiphenyls) was measured as well as environmental parameters (water temperature, salinity, total suspended solids, turbidity, chlorophyll a, pheopigments) and mussel phycotoxin contamination. Two locations differently exposed to the plume of the Vilaine River were compared. Both temporal and inter-site variations of these biomarkers were studied. Our results show that reproduction cycle and environmental parameters such as temperature, organic ontaminants, and algal blooms could strongly influence the biomarker responses. These observations highlight the necessity to conduct integrated environmental approaches in order to better understand the causes of biomarker variations.  相似文献   
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Environmental Science and Pollution Research - This work is the first study about the joint effect (influence) of carbon dioxide emissions (CO2) from transport and anemia influence on under-five...  相似文献   
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Subsocial spiders demonstrate an intermediate stage in the evolution of permanent sociality. Cooperative hunting is an important attribute of their sociality, but has not been documented in subsocial arthropods. After cannibalizing their mother, young of the subsocial spider Amaurobius ferox (Araneae, Amaurobiidae) remain together for several instars and feed communally. We monitored the collective prey capture behavior of the spiderlings. All the clutches showed collective capturing sequence (latency–orientation–moving–touching–seizing–feeding) toward the prey that was 10 times more massive than each individual. The first three individuals that exhibited attacking behavior were responsible for 90% of the total number of attacks, while 68% of the individuals within the group never exhibited attacks during the first 10 min following the introduction of prey into the communal web. First arriving individuals at the prey most often seized the antennae and legs of the prey, which probably facilitate access to the prey for subsequent individuals. The spiderlings that arrived later occupied more likely the abdomen and thorax, which contain more nutrition than the extremities occupied earlier. The individual apportionment of collective hunting behavior suggests a coordinated teamwork among individuals.  相似文献   
370.
Sixteen certified crane operators performed several series of boom movements toward a segment of a typical power line using a 100-ton lifting capacity crane equipped with an 18-m boom, a single lifting cable, and a hard ball hook. The operators were instructed to stop the crane movement when the lifting cable reached the edge of the danger zone located 3 m from the power line. To achieve each maneuver, they evaluated the distance between the nearest wire and their crane using two methods: free sighting and the use of highly visible markers delineating the edge of the danger zone. The dependent measure was the distance between the lifting cable and the edge of the danger zone. Results showed that operators were generally unreliable when judging the distance between their crane and the power line when sighting the power line directly, but the use of markers proved to be much more precise and reliable in targeting the edge of the danger zone.  相似文献   
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