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201.
Residues of pesticides were surveyed in 132 samples of cow milk collected from bulk transports (38 samples of raw milk) and market (94 samples of pasteurised milk). These samples were analysed by the multiresidue analytical method DFG S19 for pesticide contamination. More than 70 active substances were studied and the identification and quantification were made by gas chromatographic technique. The results showed that 0.76% of samples were contaminated with HCH (alpha isomer) and 10.60% with endosulfan (alpha and beta isomers). Both pesticides, endosulfan and HCH, found in milk samples, indicated their use in agriculture practices, although legislation in Brazil does not permit the use of HCH since 1985 and endosulfan can be used only in a few crops. These compounds should not be present in milk because there are implications on human health. Organophosphorus, carbamates, pyrethroids, herbicides, and fungicides were not detected in cow's milk samples.  相似文献   
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This paper first introduces our present knowledge of the origin of mitochondria and chloroplasts, and the organization and inheritance patterns of their genomes, and then carries on to review the evolutionary processes influencing mitochondrial and chloroplast genomes. The differences in evolutionary phenomena between the nuclear and cytoplasmic genomes are highlighted. It is emphasized that varying inheritance patterns and copy numbers among different types of genomes, and the potential advantage achieved through the transfer of many cytoplasmic genes to the nucleus, have important implications for the evolution of nuclear, mitochondrial and chloroplast genomes. Cytoplasmic genes transferred to the nucleus have joined the more strictly controlled genetic system of the nuclear genome, including also sexual recombination, while genes retained within the cytoplasmic organelles can be involved in selection and drift processes both within and among individuals. Within-individual processes can be either intra- or intercellular. In the case of heteroplasmy, which is attributed to mutations or biparental inheritance, within-individual selection on cytoplasmic DNA may provide a mechanism by which the organism can adapt rapidly. The inheritance of cytoplasmic genomes is not universally maternal. The presence of a range of inheritance patterns indicates that different strategies have been adopted by different organisms. On the other hand, the variability occasionally observed in the inheritance mechanisms of cytoplasmic genomes reduces heritability and increases environmental components in phenotypic features and, consequently, decreases the potential for adaptive evolution.  相似文献   
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This paper includes the proposals made in the report “Basis for a National Strategy for Coastal Zone Management” prepared for the Portuguese Ministry of Environment, Territorial Planning and Regional Development. The final version of that report was presented in June 2006. This paper describes a theme framework followed by a discussion of concepts. Nine Primary Principles, eight Principal Objectives, and 37 Strategic Options for an Integrated Coastal Zone Management are then presented. These Strategic Options are set hierarchically according to their sequential priority, identifying the dominant types of Associated Measures. The analysis of these arrives at a set of Structural Measures, which interlink and aggregate various actions and propose a new method of integrated management for the coastal zone, which includes the “Legal Basis of Coastal Zone”; the Organization System; the Action Plan and Monitoring.  相似文献   
206.
Addendum     
Bags of S. auriculatum and a low‐volume aerosol sampler with filters were exposed, in parallel, to the urban atmosphere of Oporto at four sampling points and for about two months periods, between 1991 and 1994. The levels of lead in the moss (weekly samples) and in the filters (daily samples) were determined by atomic absorption spectrophotometry and the results were compared. In dry weather periods (relative humidity ≤ 76%) the rate of lead uptake by moss was approximately constant and proportional to the levels of the metal in atmospheric aerosols. A converting factor (CF = lPbmoss l (μg/g.day)/ l Pbair l (μg/m3)) allowed conversion of the lead levels in S. auriculatum to those in the atmospheric aerosols. Because the moss fixed lead from gas, aerosol and particulated matter, the rate of sorption depends markedly on the distance to the lead sources (traffic) and on surrounding obstacles which retain particles. Therefore, specific calibration by mechanic monitoring at each point of sampling is required when moss bag samplers are used to provide quantitative information about lead levels in the atmosphere. In wet weather periods, higher but irregular rate of lead uptake was observed. In contrast, the lead levels in atmospheric aerosols decreased when the humidity increased due to wet deposition. Therefore, no proportionality between the lead levels in the moss and in the air were found.  相似文献   
207.
The trend of companies focusing ever stronger on their core businesses has led to outsourcing of certain activities, e.g. maintenance, and even to selling out parts of industrial plants. This is the case also in Finland. Clusters of neighbouring companies, commonly called industrial parks, have been formed. In these multi-company parks safety and environmental responsibilities are not always clear and the risk map has changed. It has become evident that Finnish legislation has not followed this development of the industrial sector and the formation of industrial and technology parks.A Finnish project on the safety in chemical industrial parks has studied how safety and environmental issues can be best managed in multi-company chemical parks, and how the current legislation in Finland supports companies facing problems accentuated in or specific to industrial parks. The outcome outlines the identified challenges as well as the benefits of cooperation between the independent companies in industrial parks.  相似文献   
208.
Concentrations and Pools of Heavy Metals in Urban Soils in Stockholm,Sweden   总被引:8,自引:0,他引:8  
The concentrations of heavy metals (Cd, Cr, Cu, Hg, Ni, Pb andZn) and arsenic (As) were surveyed and the metal pools estimatedin soils in Stockholm Municipality. The sampling sites were distributed all over the entire municipality with a higher sampling density in the city centre. Soils were sampled to a maximum depth of 25 to 60 cm. Soil texture, total-C content, electrical conductivity and pH were analysed. Heavy metal concentrations were determined after wet digestion with boiling7 M HNO3.The results showed a wide range in heavy metal concentrations, as well as in other soil properties. The city centre soils constituted a rather homogeneous group whereas outside this areano geographical zones could be distinguished. These soils were grouped based on present land use, i.e. undisturbed soils, public parks, wasteland (mainly former industrial areas), and roadside soils. The city centre and wasteland soils generally hadenhanced heavy metal concentrations to at least 30 cm depth compared to park soils outside the city centre and rural (arable)soils in the region, which were used to estimate background levels. For example, the mean Hg concentration was 0.9 (max 3.3)mg kg-1 soil at 0–5 cm and 1.0 (max 2.9) at 30 cm depth in the city centre soils, while the background level was 0,04 mg kg-1. Corresponding values for Pb were 104 (max 444) and135 (max 339) mg kg-1, at 0–5 and 30 cm, respectively, while the background level was 17 mg kg-1.The average soil pools (0–30 cm depth) of Cu, Pb and Zn were 21,38 and 58 g m-2 respectively, which for Pb was 3–4 timeshigher and for Cu and Zn 1.5–2 times higher than the backgroundlevel. The total amount of accumulated metals (down to 30 cm)in the city centre soils (4.5*10 6 m2 public gardens and green areas) was estimated at 80, 1.1, 120 and 40 t for Cu, Hg, Pb and Zn, respectively. The study showed (1) thatfrom a metal contamination point of view, more homogeneous soilgroups were obtained based on present land use than on geographicdistance to the city centre, (2) the importance of establishing a background level in order to quantify the degree of contamination, and (3) soil samples has to be taken below the surface layer (and deeper than 30 cm) in order to quantify theaccumulated metal pools in urban soils.  相似文献   
209.
We studied the use of polyvinil chloride pipes (PVC pipes) by frogs as artificial shelters in a Coastal Plain forest in the Vale Natural Reserve, north of Espírito Santo state, southeastern Brazil from June 2015 to May 2016. We used 14 plots distributed in the Coastal Plain Forest following the RAPELD methodology of sampling. The frogs were sampled in transects along the plots, using the active search method, with visual and auditory sampling. We recorded two species of frogs (Aparasphenodon brunoi and Scinax argyreornatus) using PVC pipes as shelters in the plots in the Forest. Of the 468 PVC pipes established along plots, 38 of them (8.1%) were used as shelter by the frogs. For both frog species, about 33% of microhabitats used in the forest were the interior of PVC pipes. We concluded that the PVC pipes might constitute artificial shelters for at least two of the frog species living in the community of the Coastal Plain Forest, potentially being of relevance in conservation programs. In altered areas and those in which there has been the loss of types of microhabitats, the addition of these PVC pipes as artificial shelters may represent additional and complementary microhabitats to keep or increase the population stocks of arboreal and semi-arboreal frog species and having a size that allow them entering the shelter. These artificial shelters can play an important role in conservation of these frogs in fragmented areas where the availability of the microhabitats of these frog species were locally reduced.  相似文献   
210.
We studied the responses of micropropagated, northern provenances of downy, mountain and silver birches to elevated ozone (O3) and changing climate using open-top chambers (OTCs). Contrary to our hypothesis, northern birches were sensitive to O3, i.e. O3 levels of 31-36 ppb reduced the leaf and root biomasses by −10%, whereas wood biomass was affected to a lesser extent. The warmer and drier OTC climate enhanced growth in general, though there were differences among the species and clones, e.g. in bud burst and biomass production. Inter- and intra-specific responses to O3 and changing climate relate to traits such as allocation patterns between the above- and belowground parts (i.e. root/shoot ratio), which further relate to nutrient and water economy. Our experiments may have mimicked future conditions quite well, but only long-term field studies can yield the information needed to forecast responses at both tree and ecosystem levels.  相似文献   
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