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171.
Quantitative information on the contribution of dust storms to atmospheric PM10 (particulate matter with an aerodynamic diameter ≤10 µm) levels is still lacking, especially in urban environments with close proximity to dust sources. The main objective of this study was to quantify the contribution of dust storms to PM10 concentrations in a desert urban center, the city of Beer-Sheva, Negev, Israel, during the period of 2001–2012. Toward this end, a background value based on the “dust-free” season was used as a threshold value to identify potentially “dust days.” Subsequently, the net contribution of dust storms to PM10 was assessed. During the study period, daily PM10 concentrations ranged from 6 to over 2000 µg/m3. In each year, over 10% of the daily concentrations exceeded the calculated threshold (BVt) of 71 µg/m3. An average daily net contribution of dust to PM10 of 122 µg/m3 was calculated for the entire study period based on this background value. Furthermore, a dust storm intensity parameter (Ai) was used to analyze several storms with very high PM10 contributions (hourly averages of 1000–5197 μg/m3). This analysis revealed that the strongest storms occurred mainly in the last 3 yr of the study. Finally, these findings indicate that this arid urban environment experiences high PM10 levels whose origin lies in both local and regional dust events.

Implications:The findings indicate that over time, the urban arid environment experiences high PM10 levels whose origin lies in local and regional dust events. It was noticed that the strongest storms have occurred mainly in the last 3 yr. It is believed that environmental changes such as global warming and desertification may lead to an increased air pollution and risk exposure to human health.  相似文献   

172.
Environmental Science and Pollution Research - The 5% addition of biochar in composting in rows contributes significantly to reducing volatile organic compound(VOC) emissions. When composting with...  相似文献   
173.
In many countries over the last decades, state initiatives have emerged to promote and support public participation in policy-making. Despite the emphasis on participation and deliberation, there are groups that remain outside the participatory proceedings. We follow through two case studies from Finland on how active citizen groups became excluded in the policy processes but decided to act nevertheless. Conceptually, the article tells two stories about multi-signification and improvisation in nature conservation processes from the citizen participation point of view. Using practice-oriented policy analysis, we explore the actors' conflicting interpretations of acting for “the sake of the lake”. We argue that in these kinds of complex policy processes, improvisation should be given more space.  相似文献   
174.
The feeding preferences of the coastal dolphins Pontoporia blainvillei and Sotalia guianensis in south-eastern Brazil (21o18′S–22o25′S) were assessed through the prey’s index of relative importance (IRI), total mercury concentration (Hgtot), and stable isotopic (δ15N and δ13C) to compare their efficiency in the discrimination of prey contribution to the predators’ diet. The IRI was the best tool to describe the dolphins’ preference, while Hgtot and δ15N seemed to be efficient as a trophic marker when the diet is made up of prey of varying sizes, as observed in S. guianensis. Both dolphins presented lighter δ15N than their prey species, which is an unusual pattern. However, as the sample size to isotope ratios analysis was small, especially to the dolphins, the results should be considered with caution, and further studies are necessary to corroborate these findings. The δ13C values characterized a typical coastal food chain, confirming the preferential area of these species.  相似文献   
175.
Low-molecular mass proteins rich in cysteines called metallothioneins (MT) can be considered as markers for the pollution of the environment by metals. Here, we report on suggestion for an automated procedure for the isolation of MT followed by voltammetric analysis. Primarily, we optimized the automated detection of MT using an electrochemical analyser. It was found that the most sensitive and repeatable analyses are obtained at a temperature of 4 °C for the supporting electrolyte. Further, we optimized experimental conditions for the isolation of MT by using antibody-linked paramagnetic microparticles. Under the optimal conditions (4 h long interaction between the microparticles and MT), the microparticles were tested on isolation of various amounts of MT. The lowest isolated amount of MT by antibody-linked paramagnetic microparticles was 5 μg ml(-1) of MT (50 ng). The automated procedure of MT isolation was further tested on isolation of MT from guppy fish (Poecilia reticulata) treated with silver(i) ions (50 μM AgNO(3)). The whole process lasted less than five hours and was fully automated. We attempted to correlate these results with the standard method for MT isolation. The correlation coefficient is 0.9901, which confirms that results are in good agreement. Moreover, the concentration of silver ions in tissues of fish treated with Ag(i) ions was determined by high performance liquid chromatography with electrochemical detection.  相似文献   
176.
The European Union’s policies regarding genetically modified food (GMF hereafter) are based on the precautionary principle and the requirement of respecting consumers’ autonomy. We ask whether the requirement of respecting consumers’ autonomy regarding GMF implies that both GMF and non-GMF products should be available in the market. According to one line of thought, consumers’ choices may be autonomous even when the both types of products are not available. A food market with only GMF or only non-GMF products does not strictly speaking compel people to buy the type of products available, and a possibility to refuse to buy is enough for consumers’ choice to be autonomous. According to another line of thought, the unavailability of GMF or non-GMF products restricts the autonomy of those consumers who are unwilling to use the only type of products (GMF or non-GMF) available in the market. From the point of view of autonomy, a food market with only GMF or only non-GMF products does not offer enough alternatives for consumers. Moreover, the whole point of the European Union’s requirement of respecting consumers’ autonomy is to enable an autonomous choice between GMF and non-GMF—not just to give a possibility to refrain from buying. However, this does not imply that producers, processors, wholesalers, retailers, or public authorities have a moral duty to see that there are both GMF and non-GMF products available in the market. The requirement to respect autonomy is prima facie in nature, and in the context of GMF, other prima facie requirements are often stronger and override it. Not only the consumers’ autonomy of choice but also environmental values, other people’s well-being, and the autonomous choice of farmers, retailers, and other relevant parties should be respected. Thus, according to the both lines of thought, the requirement to respect consumers’ autonomy of choice does not imply that there should be both GMF and non-GMF products available in the market.  相似文献   
177.
178.
Journal of Polymers and the Environment - The purpose of this study was to investigate the phosphorus (P) adsorption mechanism, kinetic, isothermal and thermodynamic parameters using alginate-like...  相似文献   
179.
Environmental Science and Pollution Research - We analyze potential Late Holocene metal contamination along a sediment core collected in the distal zone of Ria de Vigo (North Spain). Statistical...  相似文献   
180.
Individuals’ food choices are intimately connected to their self-images and world views. Some dietary choices adopted by consumers pose restrictions on their use of genetically modified food (GMF). It is quite generally agreed that some kind of labeling is necessary for respecting consumers’ autonomy of choice regarding GMF. In this paper, we ask whether the current practice of mandatory labeling of GMF products in the European Union is a sufficient administrative procedure for respecting consumers’ autonomy. Three issues concerning this question are discussed. First, we argue that labeling needs to be accompanied by relevant and understandable information on genetic modification, genetically modified food, and the European practice of GMF labeling. Second, we claim that this type of informing makes it less likely that consumers start to avoid GMF products just because labels make them suspicious of the products. It is further noted that even though some consumers may react to labels this way, labels do not restrict their autonomy of choice. Third, a need for more precise labels indicating the source of the transferred gene is considered. It is found out that such labels are not morally necessary when also non-GMF products are available and no relevant differences (such as differences in price and healthiness) exist between them and GMF products. However, in some other cases more precise labels may be needed for respecting consumers’ autonomy of choice.  相似文献   
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