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321.
This study describes the results of a field trip to the area affected by the 12 May, 2008, Wenchuan earthquake to analyse its impact on industrial facilities. The damage severity correlates well with the age of the plant, with older facilities having suffered more extensive and severe damage than those built more recently according to the latest design codes. The main cause of worker death and injury was the collapse of warehouses, office and manufacturing buildings. This concerned mostly concrete structures with insufficient confinement or poor reinforcement. The falling debris resulted in equipment damage and loss, as well as pipe severing and crushing. Pipes were also severed or bent when connected tanks were displaced or buildings collapsed. Numerous hazardous-materials releases occurred with spills being the dominant accident scenario. In some sites soil–liquefaction induced damage was evident, highlighting the need to consider potential site effects when selecting the location for a facility. The impact of the Wenchuan earthquake on chemical facilities confirms the findings from other earthquakes in terms of typical Natech damage and failure modes, as well as of hazardous-materials release potential and mechanisms.  相似文献   
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323.
Genetic variation (mtDNA) of the European conger eel, Conger conger, was compared across five locations in the north-eastern Atlantic (Madeira, Azores, South Portugal, North Portugal and Ireland) and one location in the western Mediterranean (Mallorca). Genetic diversity of conger eel was high, and differentiation among regions was not significant. Additionally, comparisons of element:Ca ratios (Sr:Ca, Ba:Ca, Mn:Ca and Mg:Ca) in otolith cores (larval phase) and edges (3?months prior to capture) among the Azores, North Portugal, Madeira and Mallorca regions for 2?years indicated that variation among regions were greater for edges than cores. Therefore, while benthic conger may display residency at regional scales, recruitment may not necessarily be derived from local spawning and larval retention. Furthermore, data from otoliths suggest a separated replenishment source for western Mediterranean and NE Atlantic stocks. The combination of genetics and otolith chemistry suggests?a population model for conger eel involving a broad-scale dispersal of larvae, with limited connectivity for benthic juvenile life stages at large spatial scales, although the existence of one or multiple spawning grounds for the species remains uncertain.  相似文献   
324.
The introduction of genetically modified plants into the environment has been marked by different positions, either in favor of or against their release. However, the problem goes well beyond such contradictory positions; it is necessary to take into account the legislation, ethics, biosafety, and the environment in the considerations related to the release of genetically modified organisms (GMOs). To this end, the Brazilian Committee of Biosafety (CTNBio), a consultative and deliberative multidisciplinary collegiate, provides technical and advisory support to the Brazilian Federal Government. This committee consists of scientists and non-scientists who participate in evaluating the dossiers of companies that are requesting approval by the Brazilian Government; consequently, the aim of this study was to investigate whether commercial approvals of GMOs were associated with the profile of the CTNBio members. Research was based on the minutes taken at CTNBio meetings carried out from 2006 up to 2009, considering law 11.105/2005 and the Constitution of 1988 as legal frameworks, to determine the number of voters in favor of or against releasing genetically modified Bt-maize, Bt-cotton, and herbicide resistant soybeans to be used in Brazilian agriculture. Via the internet, we had access to the curriculum vitae of the CTNBio members through the Plataforma Lattes database of the National Council for Scientific and Technological Development (CNPq), where we found their area of expertise. CTNBio members were divided into expert-for, expert-against, non-expert-for, and non-expert-against. Results showed that CTNBio decisions could be based on technical criteria as well as on the policy of the institution that expert-members were representing.  相似文献   
325.
Conclusions  The results are at least as good as those obtained with much more sophisticated models. Furthermore, the models can be easily run on a simple PC. This approach may provide a good diagnostic network (as seen in Bilbao) with real-time, short-term prognostic capabilities for a given location. The models have been built for Bilbao and are applicable only in this location. However, using the same methodology, similar results could be obtained in other environments if a good diagnostic network is available. The full paper is published in the Internet journal ‘Gate to EHS (Environmental and Health Science)’, in June 2001, and can be called up and cited by way of the DOI:http://dx.doi.org/10.1065/ehs2001.06.009  相似文献   
326.
This paper describes the application of liquid chromatography-tandem mass spectrometry (LC/MS-MS) for analysis of residues of forchlorfenuron (CPPU), a new plant growth regulator, in watermelons, after a sample preparation step based on the buffered Quick, Easy, Cheap, Effective, Rugged and Safe extraction method. Analytical determinations were carried out in a triple quadrupole system fitted with an electrospray interphase operating in the positive ionisation mode (ESI+). Three simultaneous MS-MS transitions of the quasi-molecular ion m/z 248 (precursor ion) were monitored for data adquisition (248 > 129, 248 > 155, and 248 > 248), using the transition 248 > 129 for quantitation. Recovery studies on watermelons at levels of 1–200 μ g/kg, performing five replicates at each level and using bracketing single-level calibration with matrix-matched standards for quantitation, gave forchlorfenuron mean recoveries ranging from 82 to 106% with relative standard deviations (RSD) lower than 18%. The limit of determination was established at 1 μ g/kg. The method was applied to evaluate the persistence of forchlorfenuron residues in watermelons grown in plastic greenhouses, after applying an individual spray treatment to the flower ovary at the anthesis stage (45 μ g/flower and 60 μ g/flower for cv “Extazy” and cv “reina de corazones” watermelons, respectively). One month after treatment, 20 “Extazy” watermelon units (1.5–2 kg/unit) and 20 “Reina de corazones” watermelon units (4–5 kg/unit) were collected and analyzed individually. None of the samples contained forchlorfenuron residues higher than 1 μ g/kg.  相似文献   
327.
This study focuses on the investigation of the kinetics of municipal solid waste composting in three full-scale mechanical–biological treatment (MBT) plants. The aims were to test a kinetic model based on volatile solids (VS) content change for describing the composting process in MBT plants, and to identify the model parameters that affected the estimation of the reaction rate constant most. To achieve this, VS content and several environmental conditions, namely temperature, moisture content, oxygen concentration and total bulk density were monitored throughout the composting process. Experimental data was fitted with a first-order kinetic model, and a rate constant (k) characteristic of composting under optimum environmental conditions was obtained. The kinetic model satisfactorily described the experimental data for the three MBT plants. k values ranged from 0.043 ± 0.002 d?1 to 0.082 ± 0.011 d?1. Sensitivity analysis showed that the model parameters that most affected the estimation of k were the initial biodegradable volatile solids content, the maximum temperature for biodegradation and the optimum moisture content. In conclusion, we show for the first time that full-scale MBT plants can be successfully modelled with a composting kinetic model.  相似文献   
328.
This work concerns the contingent valuation of endangered species. Specifically, it is devoted to quantify and model the value of the brown bear and its habitat in a society in the north of Spain. A single-bound dichotomous choice format for the valuation problem has been chosen. The main models to deal with this format will be recalled. In order to estimate the models, a multistage random sampling method has been developed, namely, two stratified random samplings and a final random routes sampling were carried out. The experiment was designed by taking into account the results of a pilot survey with open format questions. In particular, the total sample size has been determined by estimating the distribution of the errors by bootstrap, and the bid prices were fixed according to the pilot information. The results indicate that the target society gives more value to the brown bear than the one considered in the law in force.  相似文献   
329.
A procedure to evaluate mine rehabilitation practices during the operational phase was developed and validated. It is based on a comparison of actually observed or documented practices with internationally recommended best practices (BP). A set of 150 BP statements was derived from international guides in order to establish the benchmark. The statements are arranged in six rehabilitation programs under three categories: (1) planning (2) operational and (3) management, corresponding to the adoption of the plan-do-check-act management systems model to mine rehabilitation. The procedure consists of (i) performing technical inspections guided by a series of field forms containing BP statements; (ii) classifying evidences in five categories; and (iii) calculating conformity indexes and levels. For testing and calibration purposes, the procedure was applied to nine limestone quarries and conformity indexes were calculated for the rehabilitation programs in each quarry. Most quarries featured poor planning practices, operational practices reached high conformity levels in 50% of the cases and management practices scored moderate conformity. Despite all quarries being ISO 14001 certified, their management systems pay low attention to issues pertaining to land rehabilitation and biodiversity. The best results were achieved by a quarry whose expansion was recently submitted to the environmental impact assessment process, suggesting that public scrutiny may play a positive role in enhancing rehabilitation practices. Conformity indexes and levels can be used to chart the evolution of rehabilitation practices at regular intervals, to establish corporate goals and for communication with stakeholders.  相似文献   
330.
This research has been motivated by a real-life problem of a waste cooking oil collection system characterized by the existence of multiple depots with an outsourced vehicle fleet, where the collection routes have to be plan. The routing problem addressed allows open routes between depots, i.e., all routes start at one depot but can end at the same or at a different one, depending on what minimizes the objective function considered. Such problem is referred as a Multi-Depot Vehicle Routing Problem with Mixed Closed and Open Inter-Depot Routes and is, in this paper, modeled through a mixed integer linear programming (MILP) formulation where capacity and duration constraints are taken into account. The model developed is applied to the real case study providing, as final results, the vehicle routes planning where a decrease of 13% on mileage and 11% on fleet hiring cost are achieved, when comparing with the current company solution.  相似文献   
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