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61.
In order to develop small islands, not only must a vital agricultural system be maintained, but the range of opportunities for tourism must be increased with respect to both the seaside and the environmental features of the rural landscape. As an alternative to the traditional and economically declining ones, many innovative production processes can be identified, but their success depends on their interaction with the physical, biological, economic and social environment. In order to identify the main nodes and the most critical interactions, so as to increase the probability of success of a new productive process, a methodological approach based on the science of complexity is proposed for the cultivation of capers (Capparis spinosa L.) on the island of Pantelleria. The methodology encompasses the identification of actors and factors involved. the quantitative evaluation of their interactions with the different stages of the productive process, and a quasiquantitative evaluation of the probability that the particular action will be performed successfully. The study of “traditional,” “modernized,” and “modernized-sustainable” processes, shows that the modernized-sustainable process offers mutually reinforcing opportunities in terms of an integrated development of high-quality agricultural products and the enhancement of environmental features, in conjunction with high-efficiency production techniques, in conjunction with high-efficiency production techniques, in a way that suits the development of Pantelleria. There is a high probability of failure, however, as a result of the large number of critical factors. Nevertheless, the present study indicates which activities will enhance the probability of successful innovation in the production process.  相似文献   
62.
Bean plants (Phaseolus vulgaris L. cv Lit) were treated with N-[2-(2-oxo-1-imidazolinidyl)ethyl]-N'-phenylurea (EDU) (150 microg ml(-1)) in hydroponic conditions. The EDU concentration in different plant tissues was measured by HPLC. EDU accumulated in leaves and persisted for more than 10 days showing a slow degradation. Using five different EDU concentrations, a significant relationship between EDU concentration in nutrient solution, ozone tolerance and EDU concentration in leaves was shown. Leaves which contained more EDU were less sensitive to ozone damage. Investigations on protoplasts and cell cultures showed that EDU did not enter the cells. Possible implications of EDU accumulation in the leaf apoplast are discussed.  相似文献   
63.
A population dynamic model for Tapes philippinarum has been developed, using experimental data for the estimation of mortality, and literature information for recruitment. The population dynamic model has been coupled to a eco-physiological model of T. philippinarum previously developed, in order to simulate the evolution of individual size and number of individuals in each age class.The resulting age-size class model has been used to analyse the implication of different scenarios of fishing/harvesting of the bivalve in the lagoons of the Northern Adriatic Sea, where fishery and aquaculture represent important economic activities.Ten years long simulations have been performed, in which initial density, harvesting efficiency, minimum harvested size, were varied. Comparisons between the different strategies are made in term of total yields and bio-economic income. The model gives suggestions on the optimal fishing effort, in case of fishery, and on optimal seeding size and seeding moment, in case of aquaculture.A discussion of model results provides indications on harvesting policies which are appropriate from ecological-economical point of view. The final result is that economically more profitable strategies coincide with ecologically more conservative policies.  相似文献   
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65.
The environmental decision-maker is aware of the increasing difficulties in finding sufficient financial resources for nature conservation. So he must focus his attention on ecological situations that more than the others merit considering and defending because of elevated value but also because of risk for their intrinsic characteristics and for human pressure acting on them. Usually an ecological scientist focuses his attention on the natural patches of the landscape, analyzing their peculiar ecological traits forgetting that, even if we want to protect some environmental critical situations, this can be done only moving to the administrative partition of the territory since the central and local environmental stakeholders have primary interest in providing funds to those involved in those critical situations. The present work shows a methodological approach, consisting of a set of statistical and geoinformational tools, considering both ecological and socio-demographical indicators. The goal is not simply to give some general guidelines for environmental policies to the involved stakeholders but focuses more on finding out which administrative local partitions in a study area are more worthy to receive urgently the priority funds for biodiversity protection to face critical environmental situations often due to a combination of intrinsic ecological parameters and external human pressure ones. Obtaining results that cover 5% of the Communes involved in the area seems to be a realistic result that a decision-maker can support and fund. Methodologically and geospatial data analytically, the investigation offers interesting challenges for surveillance geoinformatics of hotspot detection and prioritization, because of the presence of multiple hotspots and multiple sets of multiple indicators.  相似文献   
66.
The paper deals with the general approach and features of the computer image generation for job simulation (CIGJS) method, as specially developed to support the Job Safety Analysis (JSA) technique.Starting from some general considerations on the occupational safety and health statistical data collection in Italy, when compared to US methodology, the paper provides an overview of the CIGJS method, developed to improve the effectiveness and usability of the traditional JSA.A case study is discussed in order to highlight how CIGJS makes the use of the JSA technique possible also at the design stage (this being fundamental according to a Prevention through Design approach), and allows to control the effectiveness of the adopted countermeasures.The application of the method complies with the basic European Directives requirements both on workers’ safety and health and on machinery analysis.Furthermore, CIGJS may substantially aid workers’ education and training, to the point of being a possible simulation-training device.  相似文献   
67.
The present study describes a novel application for use in the monitoring of municipal solid waste, based on distributed sensor technology and geographical information systems. Original field testing and evaluation of the application were carried out in Pudong, Shanghai (PR China).The local waste management system in Pudong features particular requirements related to the rapidly increasing rate of waste production. In view of the fact that collected waste is currently deployed to landfills or to incineration plants within the context investigated, the key aspects to be taken into account in waste collection procedures include monitoring of the overall amount of waste produced, quantitative measurement of the waste present at each collection point and identification of classes of material present in the collected waste. The case study described herein focuses particularly on the above mentioned aspects, proposing the implementation of a network of sensorized waste containers linked to a data management system.Containers used were equipped with a set of sensors mounted onto standard waste bins. The design, implementation and validation procedures applied are subsequently described. The main aim to be achieved by data collection and evaluation was to provide for feasibility analysis of the final device. Data pertaining to the content of waste containers, sampled and processed by means of devices validated on two purpose-designed prototypes, were therefore uploaded to a central monitoring server using GPRS connection. The data monitoring and management modules are integrated into an existing application used by local municipal authorities.A field test campaign was performed in the Pudong area. The system was evaluated in terms of real data flow from the network nodes (containers) as well as in terms of optimization functions, such as collection vehicle routing and scheduling. The most important outcomes obtained were related to calculations of waste weight and volume. The latter data were subsequently used as parameters for the routing optimization of collection trucks and material density evaluation.  相似文献   
68.
The identification of an indicator for monitoring pesticides is a very effective analytical approach because it allows one to schedule and simplify the analytical routine. In this study, a new indicator has been designed, which has to be able to define a scale of priorities in the pesticides monitoring. A starting equation was developed involving the escaping tendency of a given substance from a phase (based on the Mackay model I level). The reliability of the indicator was tested by application to a model system, consisting of a defined and limited area, choosing water as matrix over a period of 6 years. A group of marker compounds was also defined to implement the predictive efficacy of the indicator. The results obtained by modeling were compared to those obtained by experimentation of the same model system. The indicator was subsequently and appropriately modified creating a new equation, including a kinetic factor, which considers the environmental degradation processes. The effect of the rectified indicator was consistent with the sales data list of compounds, when applied to the markers. The indicator developed in this study, tested as a model on specific area-phase-period (Province of Siena, water phase, 2000?C2006), is applicable to any other area-phase-period, adjusting the partition value of the Mackay model for the case under study.  相似文献   
69.
This study aims to investigate the use of metallothionein as a biomarker and its environmental impact on aquatic systems. According to the species’ characteristics, the interactions of toxic elements with living organisms in marine water can lead to biomagnifications in the trophic chain or bioconcentration of what is in the water. In many aquatic organisms, the presence of metallothionein proteins was studied. The chemical analysis of these bioindicators establishes, therefore, a sensitive method for the measurement of bioavailability which, over the years, allows for the quantification of the current pollution agents in the environment. Two study areas were selected along the Latium coasts. They are differentiated by their economic activities and their kind and level of environmental impact (mainly on marine pollution). These areas were selected in order to differentiate the maximum degree of both economic development and environmental quality. In particular, the presence of pollutants in the sea due to land activities was evaluated to compare the quality of the fishing products obtained from locations subject to various environmental impacts. The heavy metal concentrations were evaluated in water samples taken from different 30 sections of the fishes in order to understand the metabolism and origin of these contaminants. The primary metals studied were: mercury (Hg), zinc (Zn), nickel (Ni), lead (Pb), cadmium (Cd), and copper (Cu). All data produced were analyzed via multivariate analyses in order to provide a final and reliable indicator.  相似文献   
70.
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