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921.
The purpose of this study was to investigate the climate change impacts, vulnerability and adaptive capacity of the electrical energy sector in Cyprus. Spatial vulnerability of the island was assessed using the degree-day indicator to investigate heating and cooling demands in the near future using daily temperature projections from regional climate models (RCMs). Using daily electrical energy consumption data for the present climate, an impact model linking consumption and temperature was constructed and this relationship was projected to the future climate using the data from the RCMs and assuming the same technology use. Our impact model results showed that for the period between November and April (‘cold period’), a decreasing trend in electrical energy consumption is evident due to warmer conditions in the near future, while for the period between May and October (‘warm period’), an increasing trend in electricity consumption is evident as warmer conditions dominate by 2050. Regarding the spatial vulnerability assessment, the cooling degree-day indicator testified that major increases in cooling demand, between 100 and 200 degree-days, are expected in inland and southern regions during the summer in the near future. In addition, increases of about 20–50 degree-days are anticipated during autumn. Conversely, energy demand for heating is projected to decrease during spring and winter, especially in the higher elevation parts of the island. More precisely, reductions of about 30–75 degree-days are projected during spring, while greater reductions of about 60–90 degree-days are expected during winter in heating demand, especially for in the near future. The ability of the energy sector to adapt and follow these changes was deemed to be satisfactory reducing the overall vulnerability of the sector to future climate change.  相似文献   
922.
Epidemiological data indicate that exposure to diesel exhaust particles (DEPs) from traffic emissions is associated with higher risk of morbidity and mortality related to cardiovascular and pulmonary diseases, accelerated progression of atherosclerotic plaques, and possible lung cancer. While the impact of DEPs from combustion of fossil diesel fuel on human health has been extensively studied, current knowledge of DEPs from combustion of biofuels provides limited and inconsistent information about its mutagenicity and genotoxicity, as well as possible adverse health risks. The objective of the present work was to compare the genotoxicity of DEPs from combustion of two first-generation fuels, 7% fatty acid methyl esters (FAME) (B7) and 20% FAME (B20), and a second-generation 20% FAME/hydrotreated vegetable oil (SHB: synthetic hydrocarbon biofuel) fuel. Our results revealed that particulate engine emissions from each type of biodiesel fuel induced genotoxic effects in BEAS-2B and A549 cells, manifested as the increased levels of single-strand breaks, the increased frequencies of micronuclei, or the deregulated expression of genes involved in DNA damage signaling pathways. We also found that none of the tested DEPs showed the induction of oxidative DNA damage and the gamma-H2AX-detectable double-strand breaks. The most pronounced differences concerning the tested particles were observed for the induction of single-strand breaks, with the greatest genotoxicity being associated with the B7-derived DEPs. The differences in other effects between DEPs from the different biodiesel blend percentage and biodiesel feedstock were also observed, but the magnitude of these variations was limited.  相似文献   
923.
Biodiversity offsets are becoming increasingly common across a portfolio of settings: national policy, voluntary programs, international lending, and corporate business structures. Given the diversity of ecological, political, and socio-economic systems where offsets may be applied, place-based information is likely to be most useful in designing and implementing offset programs, along with guiding principles that assure best practice. We reviewed the research on biodiversity offsets to explore gaps and needs. While the peer-reviewed literature on offsets is growing rapidly, it is heavily dominated by ecological theory, wetland ecosystems, and U.S.-based research. Given that majority of offset policies and programs are occurring in middle- and low-income countries, the research gaps we identified present a number of risks. They also present an opportunity to create regionally based learning platforms focused on pilot projects and institutional capacity building. Scientific research should diversify, both topically and geographically, in order to support the successful design, implementation, and monitoring of biodiversity offset programs.  相似文献   
924.
With the recommendation of the EU environmental policies, the separate waste collection issue has become more and more an object of public concern. Nevertheless, Italy’s waste management performances need further assessment processes. Until recently, some areas, especially in the South, have experienced serious waste management crises, mainly due to low rates of separate waste collection (less than 10 % of solid waste generated). The aim of this paper is to analyse the driving factors that influence the separate waste collection. Relatively to the Italian provinces in the year 2011, the analysis consists of two steps. In the first step, we characterize different institutional and socio-economic contexts through a multidimensional scaling analysis. In the second step, we provide evidence about the presence of subsets among Italian provinces using cluster analysis. Results show that contexts featuring high institutional quality promote the separate collection process. Differently, tourism-oriented environments characterized by low institutional quality don’t produce positive effects on the recycling process.  相似文献   
925.
Participation in decision-making has successively developed into a guiding principle at both EU and national level. However, diverse perspectives exist on what the role of different interests in participative processes should be, and the legal rules regarding participation varies between different sectors; from clearly defined to virtually non-existent requirements. This may have adverse effects on the legitimacy of decisions and decision-making. This paper reviews the role of participation in the planning process in relation to natural resource development in Sweden, as guided by EU and international law. Based on the notion of effective participation, the study illustrates the potential clashes that may result from different conceptions of participation, for instance, at various levels of governance, as well as from disparate principles for implementation in different sectors.  相似文献   
926.
927.
The design of heating, ventilation and air conditioning systems is still a challenging engineering task which requires experienced and informed decision-making. These systems have a great energy-saving potential at the system level rather than at the level of the individual products of which they are composed. European environmental product policies have been very useful in facilitating a homogeneous rating scheme which can be used to compare the energy performance of different products that provide the same service. This paper proposes a simplified design method which uses the performance of components that are regulated by European product policies to obtain the overall performance of heating systems in residential buildings. It is a flexible method and allows different product configurations to be assessed so as to optimise the system performance during the design phase. The method is tested on a real case study with domestic hot water and space heating systems. The case study shows the potential for improving the heating systems according to the performance levels of its products currently available in the market. Results of the domestic hot water system show that upgrading its storage tank to the maximum energy class (A+) could bring the highest energy savings ( 4162 kWh/y).  相似文献   
928.
The objective of this study was to evaluate whether the oxidative stress caused by aluminum (Al) toxicity is an early symptom that can trigger root growth inhibition in Macaca (Al-sensitive) and SMIC148-A (Al-tolerant) potato clones. Plantlets were grown in a nutrient solution (pH 4.00) with 0, 100 and 200 mg Al L−1. At 24, 72, 120 and 168 h after Al addition, root length and biochemical parameters were determined. Regardless of exposure time, root length of the Macaca clone was significantly lower at 200 mg Al L−1. For the SMIC148-A clone, root length did not decrease with any Al treatments. Al supply caused lipid peroxidation only in Macaca, in both roots (at 24, 72, 120 and 168 h) and shoot (at 120 and 168 h). In roots of the Macaca, catalase (CAT) and ascorbate peroxidase (APX) activity decreased at 72 and 120 h, and at 24, 72 and 120 h, respectively. At 168 h, both activities increased upon addition of Al. In roots of the SMIC148-A, CAT activity increased at 72 and 168 h, whereas APX activity decreased at 72 h and increased at 24, 12 and 168 h. The Macaca showed lower root non-protein thiol group (NPSH) concentration at 200 mg Al L−1 in all evaluations, but the SMIC148-A either did not demonstrate any alterations at 24 and 72 h or presented higher levels at 120 h. This pattern was also observed in root ascorbic acid (AsA) concentration at 24 and 120 h. The cellular redox status of these potato clones seems to be affected by Al. Therefore, oxidative stress may be an important mechanism for Al toxicity, mainly in the Al-sensitive Macaca clone.  相似文献   
929.
Fish gill importance in toxicants uptake, bioconcentration and excretion allied to meagre knowledge on branchial damage/protection responses substantiate this study. Five critical sites in Ria de Aveiro (Portugal) were assessed in comparison with a reference site (Torreira), focusing on Liza aurata gill antioxidant defences versus damage (oxidative and genetic). Only in Barra fish displayed damage (lipid peroxidation) though no differences were found in antioxidants. In all other sites, except Rio, antioxidant alterations were found. Thus, fish from Gafanha, Laranjo and Vagos showed higher total glutathione, glutathione peroxidase and catalase. Higher glutathione reductase and glutathione S-transferase activity was also found in the first and the last sites, respectively. In Laranjo, metallothionein levels were higher though lower in Gafanha and Vagos. In general, damage was not accompanied by defences weakening confirming that predicting damage based on antioxidants depletion is not straightforward. The integrated biomarker response index ranked sites as: Gafanha > Barra > Laranjo > Vagos > Rio > Torreira.  相似文献   
930.
PM2.5 is the breathable fraction of the particulate matter and some adverse health effects, such as respiratory functionality, cardiological diseases and cancer, can be in some measure attributable to this risk factor exposure. Some of the most carcinogen compounds transported by PM2.5 are nitro-compounds. In this study, a strengthened in vitro bioassay — able to predict the mutagenic/carcinogenic activity of the environmental mixtures — was conducted on PM2.5 organic extracts to define the nitro-compounds burden. PM2.5 air pollution was daily monitored, during 2006, in three cities located in the Northern part of Italy (Torino, Pavia and Verona) and the mutagenic properties of the PM2.5 organic extracts were assessed with the Ames test. The bacterial used in this study were three Salmonella typhimurium strains: TA98, nitroreductase-less mutant TA98NR and YG1021 carrying a nitroreductase-producing plasmid. The annual PM2.5 mean level measured in Torino was 46.5 (± 31.6) μg/m3, in Pavia 34.8 (± 25.1) μg/m3, and in Verona 37.3 (± 27.8) μg/m3, while the mutagenicity expressed as TA98 net reverants/m3 was 28.0 (± 22.1), 28.3 (± 24.9), and 34.2 (± 30.9) respectively. Monthly pool bioassays, conducted with the three different strains, showed a greater mutagenic response of the YG1021 in each city. The relationship among the mutagenic answers for YG1021:TA98:TA98NR was about 6:3:1 (p < 0.001). Over nitroreductase activity enhanced the response of 2.2, 2.0 and 1.7 times for Torino, Pavia, and Verona (ANOVA Torino p < 0.05) respectively. Without nitroreductase activity the genotoxicity was limited. These biological findings are able to describe a relevant role played by the nitro compounds in the mutagenic properties of the urban PM2.5 in the Padana plain; moreover the bacterial nitroreductase plays a predominant role in DNA interaction primarily for Torino PM2.5 extracts.  相似文献   
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