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11.
This article investigates the impact that the electricity tariff reform is likely to have on investments in renewable energies (i.e., photovoltaics) and the adoption of energy efficiency measures (i.e., installation of heat pumps and efficient home appliances) in the residential market in Italy. The study develops detailed cost comparisons and simulations considering two different investment scenarios (before and after the reform) to conclude that the reform will: (i) have a negative impact on investments in photovoltaic systems; (ii) favor the adoption of energy efficiency measures, such as efficient home appliances.  相似文献   
12.
A compost isolated humic acid-like (cHAL) material was pointed out in previous work for its potential as auxiliary in chemical technology. Its potential is based on its relatively low 0.4gL(-1) critical micellar concentration (cmc) in water, which enables cHAL to enhance the water solubility of hydrophobic substances, like phenanthrene, when used at higher concentrations than 0.4gL(-1). This material could be obtained from a 1:1 v/v mixture of municipal solid and lignocellulosic wastes composted for 15 days. The compost, containing 69.3% volatile solids, 39.6% total organic C and 21C/N ratio, was extracted for 24h at 65 degrees C under N2 with aqueous 0.1molL(-1) NaOH and 0.1molL(-1) Na4P2O7, and the solution was acidified to separate the precipitated cHAL in 12% yield from soluble carbohydrates and other humic and non-humic substances. In this work two typical applications of surfactants, i.e., textile dyeing (TD) and soil remediation by washing (SW), were chosen as grounds for testing the performance of the cHAL biosurfactant against the one of sodium dodecylsulfate (SDS), which is a well established commercial synthetic surfactant. The TD trials were carried out with nylon 6 microfiber and a water insoluble dye, while the SW tests were performed with two soils contaminated by polycyclic aromatic hydrocarbons (PAH) for several decades. Performances were rated in the TD experiments based on the fabric colour intensity (DeltaE) and uniformity (sigmaDeltaE), and in the SW experiments based on the total hydrocarbons concentration (CWPAH) and on the residual surfactant (Cre) concentrations in the washing solution equilibrated with the contaminated soils. The results show that both cHAL and SDS exhibit enhanced performance when applied above their cmc values. However, while in the TD case a significant performance effect was observed at the surfactants cmc value, in the SW case the required surfactants concentration values were equivalent to 25-125xcmc for cHAL and to 4-22xcmc for SDS. The vis-a-vis comparison of the two surfactants gave the following results: in the TD case the cHAL biosurfactant at 0.4gL(-1) yields good colour intensity and equal colour uniformity as SDS at 5gL(-1), in the SW case cHAL was found to enhance CWPAH by a factor of 2-4 relative to SDS with one soil, whereas with the other soil the two surfactants behaved similarly. The Cre data, however, showed that both soils absorbed by far more SDS (68-95%) than cHAL (12-54%). The results point out intriguing technological and environmental perspectives deriving from the use of compost isolated biosurfactants in the place of synthetic surfactants.  相似文献   
13.
The performance of different policy design strategies is a key issue in evaluating programmes for water quality improvement under the Water Framework Directive (60/2000). This issue is emphasised by information asymmetries between regulator and agents. Using an economic model under asymmetric information, the aim of this paper is to compare the cost-effectiveness of selected methods of designing payments to farmers in order to reduce nitrogen pollution in agriculture. A principal-agent model is used, based on profit functions generated through farm-level linear programming. This allows a comparison of flat rate payments and a menu of contracts developed through mechanism design. The model is tested in an area of Emilia Romagna (Italy) in two policy contexts: Agenda 2000 and the 2003 Common Agricultural Policy (CAP) reform. The results show that different policy design options lead to differences in policy costs as great as 200–400%, with clear advantages for the menu of contracts. However, different policy scenarios may strongly affect such differences. Hence, the paper calls for greater attention to the interplay between CAP scenarios and water quality measures.  相似文献   
14.
15.
Outstanding features of Mediterranean forest area are highlighted with a special reference to biodiversity and connections with forest management. The naturally originated and anthropogenic progress of the mosaic-like evolution, as well as the man-induced factors and natural constraints are described. The past and present close linkages between management and biodiversity are then analysed by means of a few, outstanding cases typical of the geographical region. The management shift on increasing economically marginal forest area (abandonment) appears to be the major force currently driving connections with inherent and associated biodiversity. The goals following the new-established environmental roles of forests have shifted towards adaptive management, namely the implementation of locally tailored rules in accordance with prominent forest functions. Key priorities to face up to the new scenarios are then discussed.Economic and policy implications are addressed with reference to multipurpose forestry and the related annual flow of outputs. It is shown the role of water-related services, as well the provision of various non-wood forest products and public goods in addition to wood and other traditional forest outputs. Reference is also made to the dualism between the Northern and the South-Eastern Mediterranean countries due to different level of economic development (and pressure of forest resources) together with very different institutional structures, i.e. public ownership in Southern and South-Eastern Mediterranean countries. Nevertheless, the situation is going to become more harmonious in the medium run by growing economic development, the affirmation of local rights on forest resources, globalisation and, above all, rural out migration and exchanges of peoples confirming the traditional role of the Mediterranean Region at cross road of South-North and Eastern-Western cultures.  相似文献   
16.
We used data from various space-borne sensors to monitor the marine ecosystem in the northwestern Mediterranean Sea, at the Costa Dorada, between the City of Barcelona and the estuary of the river Ebro. The aim of this study was to demonstrate that the combination of different remote sensing data (acquired at different electromagnetic frequencies) allows for an improved monitoring system, in particular for a better monitoring of the marine ecosystem and, hence, a better coastal zone management. We present remote sensing data acquired by the Synthetic Aperture Radar (SAR) and the Along-Track Scanning Radiometer (ATSR) aboard the Second European Remote Sensing Satellite (ERS-2), and by the Sea-viewing Wide Field-of-view Sensor (Sea WiFS) on the SeaStar satellite. By combining the different data we are able to overcome specific drawbacks of the single sensors, like an insufficient temporal coverage, or a strong dependence on weather and daylight conditions. Within the study area two main features have been selected as examples, which are well visible on many of the analysed images. The first one exhibits a higher load of chlorophyll-a and surface-active compounds and a lower sea surface temperature (SST), which is likely to be caused by the plume of the river Llobregat, southwest of Barcelona. It can clearly be seen from the imagery how the river plume is driven along the coast by the local currents. The second feature can be related to cooling water being released from a nuclear power plant and causing turbulence in the water body, which in turn gives rise to signatures visible on the ERS-SAR imagery.  相似文献   
17.
In recent years, maritime spatial planning (MSP) has become an internationally emerging, promising tool for the implementation of integrated ocean management. MSP provides the appropriate framework for public authorities and stakeholders to coordinate their action across sectors and administrative boundaries, and to optimize the use of natural resources. In November 2008 the European Commission adopted the Communication “Roadmap for Maritime Spatial Planning: Achieving Common Principles in the EU” (COM(2008) 791 final) aiming to facilitate the development of MSP by Member States and to stimulate its implementation at national and EU level. Core element of this Roadmap is a set of ten key principles for MSP in Europe. Although endorsed as valid and comprehensive, further discussion and research is needed to identify challenges, measures and tools for the key principle’s practical application. This special issue of the Journal of Coastal Conservation: Planning and Management (JCCPM) seeks to contribute to this discussion. Its purpose is to shed light from different angles on the various aspects of the mentioned ten key principles and provide lessons learned from experience in different maritime areas around the world. Taking a more scientific, rather than a political point of view, the following articles will debate the different principles, their practical handling, as well as the consequences linked to their application.  相似文献   
18.
The present study is focused on the implementation of a novel, low cost, urban grid of nanostructured chemresistor gas sensors for ammonia concentration ([NH(3)]) monitoring, with NH(3) being one of the main precursors of secondary fine particulate. Low-cost chemresistor gas sensors based on carbon nanotubes have been developed, their response to [NH(3)] in the 0.17-5.0 ppm range has been tested, and the devices have been properly calibrated under different relative humidity conditions in the 33-63% range. In order to improve the chemresistor selectivity towards [NH(3)], an Expert System, based on fuzzy logic and genetic algorithms, has been developed to extract the atmospheric [NH(3)] (with a sensitivity of a few ppb) from the output signal of a model chemresistor gas sensor exposed to an NO(2), NO(X) and O(3) gas mixture. The concentration of these pollutants that are known to be the most significant interfering compounds during ammonia detection with carbon nanotube gas sensors has been tracked by the ARPA monitoring network in the city of Milan and the historical dataset collected over one year has been used to train the Expert System.  相似文献   
19.
Hybrid composite made of glauconite and polyaniline was prepared in aqueous solution of citric acid. Scanning electron microscopy combined with energy dispersive X-ray analysis shows uniform aggregates made of glauconite microparticles and polyaniline matrix. The results of X-ray powder diffraction suggest that: (1) citric acid used for the polymerisation of aniline causes formation of emeraldine salt where macromolecular ordering in the amorphous polymer takes place; (2) no chemical interaction between glauconite and emeraldine takes place in the prepared composite. FT-IR spectra of the prepared polymer and composite show features indicating all the functional groups that are present in the diiminoquinone–diaminobenzene state of polyaniline. Thermal stability of the composite was higher than the prepared polymer suggesting the occurrence of an interphase interaction between glauconite and emeraldine. After pyrolysis in purified nitrogen the composite still remained glauconite, and ε-Fe3N together with amorphous and graphitic carbon were found as reaction products. The values of electrical conductivity and magnetization of the composite suggest that optimization of these values might be achieved based upon the relationship between glauconite and polyaniline.  相似文献   
20.
The aim of this experimental study was to evaluate the influence of anaerobic digestion and storage on indicator microorganisms in swine and dairy excreta. Samples were collected every 90 days for 15 months at eight farms, four pig, and four dairy farms, four of them having a biogas plant. Moreover, to evaluate storage effects on samples, 20 l of manure and slurry taken at each farm (digested manure only in farms with a biogas plant) were stored in a controlled climatic chamber at 18 °C, for 6 months. The bacterial load and the chemical-physical characteristics of excreta were evaluated at each sampling time, stored slurry, and manure were sampled and analyzed every 2 months. A high variability of the concentration of bacteria in the different excreta types was observed during the experiment, mainly depending on the type and time of treatment. No sample revealed either the presence of Escherichia coli O157:H7 or of Salmonella, usually linked to the temporary rearing of infected animals in facilities. Anaerobic digestion and storage affected in a significant way the reduction of indicator bacteria like lactobacilli, coliforms, and streptococci. Anaerobic digestion lowered coliforms in pig slurry (? 2.80 log, P < 0.05), streptococci in dairy manure (? 2.44 log, P < 0.001) and in pig slurry (? 1.43 log, P < 0.05), and lactobacilli in pig slurry (? 3.03 log, P < 0.05). Storage lowered coliforms and the other indicators counts, in particular in fresh wastes, while clostridia did not show a reduction in concentration.  相似文献   
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