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131.
Verónica Fuentes Ilka Straehler-Pohl Dacha Atienza Ignacio Franco Uxue Tilves Miriam Gentile Melissa Acevedo Alejandro Olariaga Josep-Maria Gili 《Marine Biology》2011,158(10):2247-2266
Rhizostoma pulmo is one of the most abundant scyphomedusae along the Mediterranean coasts. To understand changes in the population densities
of the medusa stage and its relationship with the benthic stage, we describe all developmental stages from the life cycle
of R. pulmo, from the scyphistoma stage to young medusae reared in the laboratory. Mature scyphistomae showed a mean total body length
of 1.7 mm and the average tentacle number was 16. Asexual reproduction occurred by lateral budding, podocyst and pedalocyst
production. Each strobila released up to 8 ephyrae that had a mean total body diameter of 3.5 mm. Moreover, we also present
data on the temporal and spatial distribution of the species in the Catalan Sea and the coastal lagoon on Mar Menor (NW Mediterranean)
during the years 2007–2009. In the Catalan Sea, the presence of adult R. pulmo was recorded as extended along the whole coast, but most of the observation was concentrated in the central area; the highest
abundances were recorded during the months of July and August. The highest number of observations was detected in 2008 in
coincidence with the inter-annual variation observed in the Mar Menor lagoon. 相似文献
132.
Dalcin MG Pirete MM Lemos DA Ribeiro EJ Cardoso VL de Resende MM 《Journal of environmental management》2011,92(4):1165-1173
Hexavalent chromium is frequently found in industrial effluents as a result of the industrial applications of this compound and its anti-corrosive features. However, hexavalent chromium is extremely toxic, and its discharge in water is regulated, with a maximum limit of 0.1 mg/L in accordance with legislation established by CONAMA-Brazil (no. 397, April 3, 2008). To achieve lower discharge values, it is necessary to reduce from Cr(VI) to Cr(III), which is less toxic, and an economic alternative involves biological removal of this compound. Residence time distributions (RTDs) were measured to evaluate the behavior of actual biofilter operation conditions in a biofilter flow. The medium residence time distributions used were 8 and 24 h (recommended by the legislation). To optimize this process, a central composite design was used, considering the initial chromium concentration and pH as the independent variables and the removal of hexavalent chromium as the response. The boundary curves and surface response showed optimal behavior at 3.94 mg/L [Cr(0)] and a pH of 6.2. The removal process of hexavalent chromium is mathematically described by the Michaelis-Menten kinetic model. This model appropriately represents the variation of chromium concentration along the bioreactor. 相似文献
133.
134.
Simpson AJ Lam B Diamond ML Donaldson DJ Lefebvre BA Moser AQ Williams AJ Larin NI Kvasha MP 《Chemosphere》2006,63(1):142-152
Recently it has been shown that urban surfaces are covered with a thin film which mediates the fate, distribution and accumulation of semi-volatile organic compounds in the environment. In this study we apply a combination of solution, semi-solids, and solid state nuclear magnetic resonance (NMR) methods to provide a general overview of the organic constituents. In surface film collected from 30 m2 of outside windows over an area of 12 km2 in downtown Toronto, we roughly estimate that the organic carbon is approximately 35% carbohydrate, approximately 35% aliphatics, approximately 20% aromatics, and approximately 10% carbonyl groups. Various aliphatic groups can be identified including a number of acids, alcohols, alkanes, and alkenes. Also, numerous intact aliphatic esters are apparent that have not been observed before, as well as carbohydrates. The aromatic species include a small portion that appears to be derived from a polymer of styrene, in addition a larger fraction is consistent with polyhydroxylated PAH derived material, although this assignment is tentative and based solely on 1-D NMR data only. In addition, signals from polybutadiene are present and while accurate quantification is not possible, it appears that this polymer may be up to a few percents by weight of the total organic material. 相似文献
135.
The white-rot fungus Trametes versicolor growing in submerged culture on a basal medium, with barley bran as a carbon source, produced two laccase isoenzymes LacI and LacII. The addition of metal ions to the culture medium was performed to improve the total laccase activity and to determine the effect on the production of laccase isoenzymes. From all the tested metals, only Cu2+ increased laccase activity (up to 12-fold with respect to control cultures) and T. versicolor in presence of all metals produced the two isoenzymes in different proportion with ratios of activity (LacI/LacII) varying between 0.11 and 0.51. This factor played an important role in the decolourisation of the textile dye Indigo Carmine. 相似文献
136.
Elizabeth J. Golebie Miriam Aczel Jacob J. Bukoski Sophia Chau Natali Ramirez-Bullon Mimi Gong Noah Teller 《Conservation biology》2022,36(1):e13850
Management of mangrove ecosystems is complex, given that mangroves are both terrestrial and marine, often cross regional or national boundaries, and are valued by local stakeholders in different ways than they are valued on national and international scales. Thus, mangrove governance has had varying levels of success, analyzed through concepts such as principles of good governance and procedural justice in decision-making. Although there is substantial research on case studies of mangrove management, global comparisons of mangrove governance are lacking. This research aims to fill this gap by comparing relationships among qualities of governance across mangrove social-ecological systems worldwide. Through a systematic literature search and screening process, we identified 65 articles that discussed mangrove governance and conservation. Case studies in these articles, drawn from 39 countries, were categorized as top-down, bottom-up, or comanaged and thematically coded to assess the influence of eight principles of good governance in mangrove conservation success. Across all three governance systems, the principles of legitimacy, fairness, and integration were most important in determining conservation success or failure. These principles are closely related to the concept of procedural justice, highlighting the importance of stakeholder inclusion throughout all stages of mangrove management. Thus, we recommend clearly defined roles for all governance actors, transparent communication of policy development to stakeholders, fairness in both process and outcome, and careful consideration of sustainable access to conservation resources. 相似文献