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81.
This article examines why, in spite of vast forest resources, Russia has been unable to attract foreign investors into its forest industry. A survey of 32 influential Western European forest companies indicates that purely economic factors, such as labour or raw material costs, are not the main reasons these companies refrain from investing. Instead, the companies identify a number of institutional factors: ambiguous legal systems; difficulties in negotiating with local authorities; unfair tax enforcement; and general political instability as the main impediments to FDI in the sector. These factors have led many companies to abandon previously considered investments in Russia, and also to terminate existing business relationships with Russian partners. The survey results also indicate that, while many investors in forestry were attracted by the potential for a growing Russian market in the early days of the transition period, they have become more and more aware of the many institutional obstacles challenging growth in the sector. The article concludes, therefore, that FDI in the Russian forestry sector is likely to remain low until a fundamental change takes place in the legal and political systems.  相似文献   
82.
The transport and biodegradation of 12 organic compounds (toluene, phenol, o-cresol, 2,6-, 3,5-dimethylphenol, naphthalene, 1-methylnaphthalene, benzothiophene, dibenzofuran, indole, acridine, and quinoline) were studied at a field site located on the island of Funen, Denmark, where a clayey till 10–15 m deep overlies a sandy aquifer. The upper 4.8 m of till is highly fractured and the upper 2.5 m contains numerous root and worm holes. A 1.5–2 m thick sand lens is encountered within the till at a depth of 4.8 m. Sampling points were installed at depths of 2.5 m, 4 m, and in the sand lens (5.5 m) to monitor the downward migration of a chloride tracer and the organic compounds. Water containing organic compounds and chloride was infiltrated into a 4 m×4.8 m basin at a rate of 8.8 m3 day−1 for 7 days. The mass of naphthalene relative to chloride was 0.39–0.98 for the sampling points located at a depth of 2.5 m, 0.11–0.61 for the sampling points located at a depth of 4 m, and 0–0.02 for the sampling points located in the sand lens. A similar pattern was observed for eight organic compounds for which reliable results were obtained (toluene, phenol, o-cresol, 2,6-, 3,5-dimethylphenol, 1-methylnaphthalene, benzothiophene, and quinoline). This shows that the organic compounds were attenuated during the downward migration through the till despite the high infiltration rate. The attenuation process may be attributed to biodegradation.  相似文献   
83.
Baltic Sea populations of the northern pike (Esox lucius) have declined since the 1990s, and they face additional challenges due to ongoing climate change. Pike in the Baltic Sea spawn either in coastal bays or in freshwater streams and wetlands. Pike recruited in freshwater have been found to make up about 50 % of coastal pike stocks and to show natal homing, thus limiting gene flow among closely located spawning sites. Due to natal homing, sub-populations appear to be locally adapted to their freshwater recruitment environments. Management actions should therefore not involve mixing of individuals originating from different sub-populations. We offer two suggestions complying with this advice: (i) productivity of extant freshwater spawning populations can be boosted by modifying wetlands such that they promote spawning and recruitment; and (ii) new sub-populations that spawn in brackish water can potentially be created by transferring fry and imprinting them on seemingly suitable spawning environments.  相似文献   
84.
The musculoskeletal health among 57 operators at 1 call centre in Sweden was studied with 10 monthly follow-ups, parallel to a reference group of 1,226 professional computer users in other occupations. Operators at this call centre were more symptom-loaded than the other professional computer users in spite of their younger age and shorter exposure to computer work. Symptoms were long-lasting or recurrent. Muscle tenderness and nerve affections in the neck- shoulder region were the most common specific findings and diagnoses at medical examination of incident symptom cases. More extensive studies should be done on the working conditions and health status among call centre workers.  相似文献   
85.
In order to study the ecophysiological response of a natural diatom-dominated microbial mat to an enhanced level of ultraviolet-B radiation (UVBR), intact sediment cores from a shallow microtidal bay on the Swedish west coast were incubated in an outdoor flow-through system and exposed to either no UVBR or to an artificially enhanced level of UVBR. The microbial mat was cohesive and dominated by the large (≈ 400 μm) motile diatom Gyrosigma balticum. Functional response to UVBR was assessed by measuring carbon fixation (14C) and allocation of photosynthetic products. Sediment oxygen microprofiles were measured as indicators of the balance between the photosynthetic and respiratory activity of the community. Structural variables included biomass and composition of microalgae, pigment composition (HPLC), content of UV-absorbing compounds, and composition of fatty acids. An enhanced level of UVBR resulted in significant functional changes in the microalgal community. Significantly decreased carbon fixation and lower net oxygen production (as calculated from oxygen microprofiles) suggest that primary productivity in the type of microbial mat studied is potentially sensitive to an enhanced level of UVBR. The pattern of carbon allocation hinted a change as to the photosynthetically active part of the community when exposed to UVBR, indicating a differential sensitivity among algal cells. Despite significant functional effects, pigment or algal composition were not significantly affected by enhanced UVBR. The concentration of UV-absorbing compounds was low and did not increase at UVBR exposure. Due to the short duration of the experiment (4 d), a change in algal biomass or composition was not to be expected. Moreover, the thickness of the sampled sediment layer, may have contributed to the lack of observed structural effects of enhanced UVBR. Visual observations suggested that UVBR affected the motility of G. balticum. This study, as well as other experiments with a similar diatom mat, suggest that vertical migration is a key mechanism to be further studied in relation to UVBR exposure of diatom-dominated microbial mats. Received: 7 September 1996 / Accepted: 8 October 1996  相似文献   
86.
87.
The leaching of major ions has been studied since August 1986 in two plots with different nitrogen fertilization levels and in a control plot in a 29-year-old stand of Norway spruce (Picea abies Karst.) in south-central Sweden. The fertilization started in 1967. The two fertilizer levels, both of which have caused a significant stimulation of the tree growth, correspond to an annual input of approximately 35 kg N ha(-1) and 75 kg N ha(-1) respectively, as NH4NO3. Phosphorus fertilizer is also applied. Field and laboratory incubations performed during 1986 showed that nitrification mainly occurs in the plot with the highest fertilization level, in accordance with the fact that nitrate could not be detected in the soil water in the other two plots. Fertilization has increased the ionic strength of the soil solution due mainly to sulphate in the phosphate fertilizer, but also nitrate at the highest fertilization level. This has caused an increase in total aluminium and a decline in pH. The preliminary data reported here are compared with results obtained at Swedish field sites with moderate to high levels of nitrogen deposition.  相似文献   
88.
The Chernobyl accident, and the general acidification of Swedish water systems, form the base for this project. The aims of the work have been to present results on the linkage between the concentration of Cs-137 in fish, lake load of Cs and lake characteristics, to give a preliminary prognosis on the recovery, and to put the results within a wider framework of environmental hazard analysis. A broad set of data on limnology, morphometry and drainage area conditions from 41 lakes were collected during 1986 and 1987. Cs-137 was determined in 1 + perch (Cs-pe, 1-year-old perch), water, material collected by sediment traps and from surficial sediments. The main results are as follows. The average value of Cs-pe for all lakes has dropped from 9800 Bq kg(-1) (wet) to 5040 between the 2 years. Generally, the decrease is between 5 and 90%. We have tested if any factor(s) could be specifically linked to this decrease-no such factors have been found. The concentrations of Cs in sediment traps have, on average, decreased by 80%. Very high correlations exist between Cs-pe and the caesium load as determined from the sediment traps. Between 1 and 10% (mean 3.9%) of the initial fall-out deposition to the drainage area was transported from land to water during June to August 1986. The variation in initial fall-out deposition explains 65-69% of the variability in Cs-pe; the degree of explanation (= coefficient of determination, r2) increases to about 85% if one also takes into account the lake water hardness and totP. A map showing with lakes likely to have 1 + perch with higher mean Cs-concentrations than 1500 Bq kg(-1) wet is presented. Between 4000 and 7000 lakes in Sweden appear to have Cs-pe higher than 1500 Bq kg(-1) wet, figures which emphasize the serious impact of the Chernobyl accident on the environmental conditions in Sweden.  相似文献   
89.
Nilsson S  Langaas S 《Ambio》2006,35(6):304-311
We address issues connected with international river basin management and the EU Water Framework Directive (WFD). By creating a register of River Basin Districts established under the WFD, we show that the number and area of international River Basin Districts are significant. Further, we present an assessment of international cooperation and water quality in 14 international river basins in the Baltic Sea Drainage Basin. Our results indicate that the WFD is a push forward for international river basin management in the region. However the WFD in general, and the principle of river basin management in particular, may be hard to implement in river basins shared between EU Member States and countries outside the EU. According to the study, Vistula, Pregola, and Nemunas appear to be the international basins within the Baltic Sea Drainage Basin in greatest need of intensified cooperation with regard to the state of the water quality.  相似文献   
90.
A novel technique, gas chromatography-UV spectrometry (GC-UV), was used to quantify volatile organic compounds (VOCs) in settled dust from 389 residences in Sweden. The dust samples were thermally desorbed in an inert atmosphere and evaporated compounds were concentrated by solid phase micro extraction and separated by capillary GC. Eluting compounds were then detected, identified, and quantified using a diode array UV spectrophotometer. Altogether, 28 compounds were quantified in each sample; 24 of these were found in more than 50% of the samples. The compounds found in highest concentrations were saturated aldehydes (C5-C10), furfuryl alcohol, 2,6-di-tert-butyl-4-methylphenol (BHT), 2-furaldehyde, and benzaldehyde. Alkenals were also found, notably 2-butenal (crotonaldehyde), 2-methyl-propenal (methacrolein), hexenal, heptenal, octenal, and nonenal. The concentrations of each of the 28 compounds ranged between two to three orders of magnitude, or even more. These results demonstrate the presence of a number of VOCs in indoor dust, and provide, for the first time, a quantitative determination of these compounds in a larger number of dust samples from residents. The findings also illustrate the potential use of GC-UV for analysing volatile compounds in indoor dust, some of which are potential irritants (to the skin, eyes or respiratory system) if present at higher concentrations. The potential use of GC-UV for improving survey and control of the human exposure to particle-bound irritants and other chemicals is inferred.  相似文献   
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