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1.
Two in-field campaigns were performed in 2009 to elucidate the contents of illicit psychotropic substances in airborne particulates of Italian cities. Twenty-eight localities of eight Italian regions were investigated in winter, and further eleven sites in June (14 regions in total), thanks to contribution of Regional Environmental Agencies. Cocaine was found almost everywhere, although some sites were rural or suburban. The maximum was recorded in Milan in winter (~0.39 ng m?3), and “high” values (up to ~0.16 ng m?3) in other Northern cities and in Rome. Besides cocaine, three cannabinoids will be monitored, namely Δ9-tetrahydrocannabinol, cannabidiol and cannabinol. The three compounds often affected the air at lower extents than cocaine, and sometimes resulted absent. Cannabinol accounted for up to 90% of the total. The concentrations of illicit compounds were up to six times lower in June than in winter. This decrease was probably induced by the lowering of boundary layer height typical of winter, and by the oxidizing capacity of atmosphere, which is stronger in the warm season. Compared to n-alkanes, polynuclear aromatic compounds, nicotine, caffeine and airborne particulate, cocaine seemed to follow a peculiar behaviour; in fact, meaningful (≥0.80) Pearson (linear) regression coefficients were calculated from the corresponding concentrations only at local scale (e.g. Rome), and within just one season. Improvements of the method are needed to monitor illicit drug metabolites (e.g. benzoylecgonine, ecgonine methyl ester, 9-carboxy-11-nor-Δ9-tetrahydrocannabinol), heroin and semi-volatile amphetamines.  相似文献   
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Ecotoxicological laboratory tests (lower-tier tests) are fundamental tools for assessing the toxicity of pesticides to soil organisms. In this study, using these tests under tropical conditions, we quantified the impact of the insecticides imidacloprid, fipronil, and thiametoxam, and the fungicides captan and carboxin + thiram, all of which are used in the chemical treatment of crop seeds, on the survival, reproduction, and behavior of Eisenia andrei (Oligochaeta). With the exception of imidacloprid, none of the pesticides tested caused mortality in E. andrei in artificial soils. The LC50 of imidacloprid was estimated as 25.53 mg active ingredient kg?1 of dry soil. Earthworm reproduction rates were reduced by imidacloprid (EC50 = 4.07 mg kg?1), fipronil (EC20 = 23.16 mg kg?1), carboxin + thiram (EC50 = 56.38 mg kg?1), captan (EC50 = 334.84 mg kg?1), and thiametoxam (EC50 = 791.99 mg kg?1). Avoidance behavior was observed in the presence of imidacloprid (AC50 = 0.11 mg kg?1), captan (AC50 = 33.54 mg kg?1), carboxin + thiram (AC50 = 60.32 mg kg?1), and thiametoxam (AC50 = >20 mg kg?1). Earthworms showed a preference for soils with the insecticide fipronil. Imidacloprid was the most toxic of the substances tested for E. andrei. The avoidance test was the most sensitive test for most pesticides studied, but results varied between pesticides. These results offer new insights on the toxicity of pesticides used to treat seeds in tropical regions. However, they should be complemented with higher-tier tests in order to reduce the uncertainties in risk assessment.  相似文献   
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In this work, we studied the removal of simazine from both a model and well water by adsorption on two different adsorbents: zeolite H-Y and a porous silica made in the laboratory by using the sol–gel technique. The pH dependence of the adsorption process and the isotherms and pseudo-isotherms of adsorption were studied. Moreover, an iterative process of simazine removal from both the model and well water, which allowed us to bring the residual simazine concentration below the maximum concentration (0.05 mg L?1) of agrochemicals in wastewater to be released in surface waters or in sink allowed by Italian laws, was proposed. The results obtained were very interesting and the conclusions drawn from them partly differed from what could reasonably be expected.  相似文献   
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The larval development of the newly discovered cephalocarid from Mediterranean sea, Lightiella magdalenina, was analysed using light and scanning electron microscopy. Twenty-nine larval specimens, divided into 15 metanaupliar and 2 juvenile stages of development, were found. The first six metanaupliar stages had an even number (6, 8, 10, 12, 14 and 16) of trunk segments including telson. The condition of 20 trunk segments, typical of the adult, was reached after another 4 stages by the addition of a single segment per stage. At this tenth stage, the larvae had an incomplete number of trunk limbs. Another five stages were needed to complete the cephalic appendage development, passing from the metanaupliar to the juvenile stage, characterized by loss of the naupliar enditic process of the second antenna. Trunk limbs development was completed during the last two juvenile stages. According to the ontogenetic data reported for Hutchinsoniella macracantha and Lightiella incisa, these seventeen stages probably do not represent the complete developmental series. Nevertheless, they allow us to clarify the main features of cephalocarid ontogeny and show specific differences in the development of both the trunk segments and appendages.  相似文献   
6.
A fully non-linear analysis of forcing influences on temperatures is performed in the climate system by means of neural network modelling. Two case studies are investigated, in order to establish the main factors that drove the temperature behaviour at both global and regional scales in the last 140 years. In particular, our neural network model shows the ability to catch non-linear relationships among these variables and to reconstruct temperature records with a high degree of accuracy. In this framework, we clearly show the need of including anthropogenic inputs for explaining the temperature behaviour at global scale and recognise the role of El Niño southern oscillation for catching the inter-annual variability of temperature data. Furthermore, we analyse the relative influence of global forcing and a regional circulation pattern in determining the winter temperatures in Central England, showing that the North Atlantic oscillation represents the driven element in this case study. Our modelling activity and results can be very useful for simple assessments of relationships in the complex climate system and for identifying the fundamental elements leading to a successful downscaling of atmosphere–ocean general circulation models.  相似文献   
7.
It is well-known that the total metal content in soils is not a good indicator of their harmful effects, leading to an overestimation of risks. Toxicological and environmental hazards depend on the chemical species and on its bioavailability to target organisms. Because a good estimation of bioavailability is difficult, a good compromise is to assess bioaccessibility, defined as the maximum amount of a pollutant which is potentially absorbable by a target organism. This study presents a comparison of different strategies to measure metal bioaccessibility in soils. Three procedures were applied to real soil samples with different levels of metal contamination: pseudo-total metal attack, selective sequential extractions and in vitro tests (deliberately developed to simulate human or mammals digestion). Considering the first step of the selective extraction procedure, which can provide the bioaccessible fraction for deposit-feeder organisms, data obtained for each metal were lower than those obtained from in vitro tests. Therefore, it is possible to highlight that this extraction tends to underestimate metal bioaccessibility in soils for humans, while in vitro tests certainly will overestimate bioaccessibility for organisms as invertebrates. If the sum of first and second step of sequential procedure is considered, results are quite similar to those obtained from in vitro tests, but this kind of procedure would require two days of work rather than a few hours required to perform an in vitro test. Results highlight the diversity among the differently defined bioaccessible fractions and the need to apply the most suitable procedure depending on the target organism.  相似文献   
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Environment Systems and Decisions - Functional dependencies in complex technical infrastructures can cause unexpected cascades of failures, with major consequences on availability. For this reason,...  相似文献   
10.
Results from a five month monitoring campaign of BTX (benzene, toluene and the sum of ethyl benzene, o-xylene, m-xylene and p-xylene), performed at Monterotondo, a little town 23 km NE of Rome, and correlation of the measured concentrations with meteorological and natural radioactivity data are presented and discussed. This campaign allowed us to extrapolate a pattern of the annual distribution of benzene in the town. A map, showing the average distribution of pollutants, is presented, as a useful tool to manage an appropriate policy of air pollution. A contemporary indoor-outdoor investigation has been performed at five homes and two classrooms of Monterotondo and at thirteen homes and thirteen classrooms in the outskirts of Rome. Non-smoking people and low polluted sites were chosen for this campaign, in order to highlight if commonly used domestic materials could act as internal sources. Data, obtained by employing long-term diffusive samplers, are compared with a parallel experiment showing the day-night indoor-outdoor trend. The obtained results, confirmed through statistical analysis of data, let us conclude that there is evidence of internal sources at homes whilst, in the schools, depletion phenomena prevail, probably due to the walls adsorption.  相似文献   
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