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81.
The effects of the nitrofuran furaltadone on Ulva lactuca   总被引:1,自引:0,他引:1  
The use of pharmaceuticals in the food production industry as prophylatic and therapeutic agents is necessary to promote animal health, but may entail significant consequences to natural ecosystems, especially in the cases of overdosing and use of banned pharmaceuticals. The vast effects that antibiotics released into the environment have on non-target organisms are already under the scope of researchers but little attention has been given to primary producers such as macroalgae. The present study assessed furaltadone’s, an antibacterial agent illegally used for veterinary purposes, uptake capacity by Ulva lactuca and its effect in the growth of this cosmopolitan macroalgae. Differences in macroalgal growth were shown when submitted to prophylactic and therapeutic concentrations of furaltadone in the water (16 and 32 μg mL−1, respectively). The therapeutic concentration caused higher growth impairment than the prophylactic treatment did, with 87.5% and 58% reductions respectively. Furthermore, together with data collected from the accumulation assays, with values of internal concentrations as high as 18.84 μg g−1 WW, suggest that the macroalgae U. lactuca should be included in field surveys as a biomonitor for the detection of nitrofurans.  相似文献   
82.
PM10 levels of the 16 US-EPA Priority Pollutant polycyclic aromatic hydrocarbons (PAHs) were measured from March 17 to 31, 2003, in 8-h time bins (morning, afternoon and nighttime) at Merced, a source site dominated by vehicular traffic emissions near the center of Mexico City, and at Pedregal, a receptor area located downwind in a residential area of low traffic. Along with PAH, elemental (EC) and organic carbon (OC), mass, and prevailing meteorological parameters were measured. At the source location, measured concentrations of benzo[a]pyrene (BAP), an agent suspected of being carcinogenic to humans and of causing oxidative DNA damage, reached concentrations as high as 2.04 and 2.11 ng m?3 during the morning of a weekday and the night period of a holiday. Compared with source dominated areas in Central Los Angeles, the BAP levels found in Central Mexico City are approximately 6 times higher. Benzo[ghi]perylene (BGP) levels were, in general, the highest among the target PAH, both at the source (7.2 ng m?3) and the receptor site (2.8 ng m?3), suggesting that, at both locations, exhaust emission by light-duty (LD) vehicles is an important contributor to the atmospheric PAH burden. Higher PAH concentrations were observed during the morning period (5:00–13:00 h) at the source and the receptor site. The concentrations of PAHs found predominantly in the particle-phase (MW > 202) correlated well (r = 0.57–0.71) with the occurrence of surface thermal inversions and with mixing heights (r = ?0.57 to ?0.72). Organic and elemental carbon ratios also indicated that Pedregal is impacted by secondary aerosols during the afternoon hours.  相似文献   
83.
Weekly and seasonal variations of surface ozone and their precursors – nitrogen oxides, carbon monoxide-associated with meteorological parameters (wind direction, temperature, solar radiation) – are reported. Measurements were performed continuously during 2006 at two sampling stations located in the metropolitan area of Porto Alegre, Brazil. Results have shown that O3 concentrations remained almost constant between weekdays. Levels of NOx precursors decreased especially on Sundays, due to lighter traffic. The seasonal variation has shown a maximum O3 concentration during summer and spring while NOx and NO2 have maxima at the colder months. The daily cycle of highest ozone concentrations reveals a lower nightly level and an inverse relation between O3 and NOx, evidencing the photochemical formation of O3. There are seasonal variation and source heterogeneity.  相似文献   
84.
From the perception of human populations, we can assess the changes occurring in certain landscapes and the factors that cause those changes. Such studies have proven helpful in increasing the knowledge of the history of a landscape, recognizing past formations and projecting its future. Our research objective was to determine how a landscape dominated by the palm tree Attalea speciosa, a species of ecological, economic, and cultural importance, has been changing over time by synthesizing and comparing historical documents and local perceptions. This study was conducted in Araripe Environmental Protection Area, Northeast Region, Brazil. To understand local landscape change, we interviewed active harvesters in four communities in which A. speciosa use has been documented. Historical documents were evaluated as a complement to the interview data. According to local informants, areas previously used for cultivation and animal husbandry that were abandoned or decimated by droughts in the region may have fostered the expansion of a monodominant A. speciosa forest. Furthermore, other forms of landscape management resulting from human population growth may also have affected the current and past distribution of this forest.  相似文献   
85.
The aim of this study was to validate the effectiveness of a phytoremediation procedure for metal-working fluids (MWFs) with maize plants growing in hydroponic culture in which the roots grow on esparto fibre and further improve bioremediation potential of the system with root beneficial bacteria, seeking a synergistic effect of the plant–microorganism combination. Chemical oxygen demand (COD), pH, total and type of hydrocarbons measured after phytoremediation indicated that the process with maize plants was successful, as demonstrated by the significant decrease in the parameters measured. This effect was mainly due to the plant although inoculated microorganisms had a relevant effect on the type of remaining hydrocarbons. The success of the phytoremediation process was further confirmed by two toxicity tests, one of them based on chlorophyll fluorescence measurements on maize plants and another one based on cyanobacteria, using a bioluminescent toxicity bioassay; both tests demonstrated that the phytoremediated waste was significantly less toxic than the initial non-phytoremediated MWFs.  相似文献   
86.
87.
Objective: The objective of this study was to estimate the effect of the Brazilian zero-tolerance drinking and driving law on mortality rates due to road traffic accidents according to the type of victim, sex, and age.

Methods: An interrupted time series design was used to compare yearly mortality rates due to road traffic accidents in Rio de Janeiro, Brazil, before and after the zero-tolerance drinking and driving law came into effect on June 19, 2008. Yearly mortality rates were compared according to the type of victim: pedestrian, cyclist, motorcyclist, and vehicle occupant. We used the Prais-Winsten procedure of autoregression in the analysis of time series; the outcome of this analysis was the annual percentage change in the rates. Overall and stratified analyses were conducted to investigate whether the zero-tolerance drinking and driving law may have had a distributional effect on mortality rates due to road traffic accidents depending on sex and age group; a significance level of P < .01 was accepted.

Results: From 1999 to 2016, there were 15,629 deaths due to road traffic accidents in Rio de Janeiro. The effect of the zero-tolerance drinking and driving law on overall mortality rates due to road traffic accidents in Rio de Janeiro was not statistically significant. However, among cyclists and motorcyclists aged ≥60 years and among pedestrians of both sexes and aged ≥20 years, the effect of the zero-tolerance drinking and driving law was to decrease mortality due to road traffic accidents at a yearly rate.

Conclusion: There is evidence of reduced mortality rates due to road traffic accidents among cyclists and motorcyclists aged ≥60 years and among pedestrians of both sexes aged ≥20 years in the second major Brazilian capital 9 years after the zero-tolerance drinking and driving law was adopted.  相似文献   

88.
89.
Environment, Development and Sustainability - Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is one of the biggest public health issues in the last years. The WHO has...  相似文献   
90.
The development of environmental performance policy indicators for public services, and in particular for the defence sector, is an emerging issue. Despite a number of recent initiatives there has been little work done in this area, since the other sectors usually focused on are agriculture, transport, industry, tourism and energy. This type of tool can be an important component for environmental performance evaluation at policy level, when integrated in the general performance assessment system of public missions and activities. The main objective of this research was to develop environmental performance policy indicators for the public sector, specifically applied to the defence sector. Previous research included an assessment of the environmental profile, through the evaluation of how environmental management practices have been adopted in this sector and an assessment of environmental aspects and impacts. This paper builds upon that previous research, developing an indicator framework--SEPI--supported by the selection and construction of environmental performance indicators. Another aim is to discuss how the current environmental indicator framework can be integrated into overall performance management. The Portuguese defence sector is presented and the usefulness of this methodology demonstrated. Feasibility and relevancy criteria are applied to evaluate the set of indicators proposed, allowing indicators to be scored and indicators for the policy level to be obtained.  相似文献   
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