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POTE John HALLER Laurence KOTTELAT R′egis SASTRE Vincent ARPAGAUS Philippe WILDI Walter 《环境科学学报(英文版)》2009,21(1):62-69
The aims of this study was to investigate the persistence and the growth of culturable bacterial indicators (CBI) including total
coliforms (TC) and faecal coliforms represented by Escherichia coli, enterococcus (ENT), and aerobic mesophilic bacteria (AMB) in
the surface sediments and the water column of Vidy Bay (Lake Geneva, City of Lausanne, Switzerland). The study was carried out for
60 d using microcosms containing Sewage Treatment Plant (STP) e uent and nonsterile water without CBI, as well as contaminated
and non-contaminated sediments. The e ects of water temperature and of organic matter associated with sediments on the survival of
CBI in the sediments and the water column were observed. The number of CBI colonies in the contaminated sediments of Vidy Bay and
in the STP e uent was almost identical in the order of 105–107, 104–106, 103–105, and 104–107 CFU/100 g sediment or /100 mL water
for TC, E. coli, ENT, and AMB respectively. A degradation of CBI was observed in the sediments where organic mater content was
low and in the water column at a temperature of 10°C after 5 d of experimentation. In addition, a growth of CBI was observed in the
sediment which is rich in organic matter at 20°C. The results of this study indicate: (1) the higher concentrations of the CBI observed
in di erent points in the water column of Vidy Bay may not be explained only by the recent contribution of the three potential sources
of the Bay contamination including STP and the Chamberonne and Flon Rivers, but also by the persistence, removal from sediment
and multiplication of CBI in the sediment and water column; (2) the sediment of Vidy Bay constitute a reservoir of CBI and can even
support their growth; and (3) the CBI not only survive in sediments, but also can be remobilized and increased in the water column,
therefore, it become a permanent microbiological pollution in Vidy Bay. 相似文献
637.
Pieternel A.M. Claassen Truus de Vrije Emmanuel Koukios Ed van Niel Inci Eroglu Michael Modigell Anton Friedl Walter Wukovits Werner Ahrer 《Journal of Cleaner Production》2010
The objectives and methodology of the EU-funded research project HYVOLUTION devoted to hydrogen production from biomass are reviewed.The main scientific objective of this project is the development of a novel two-stage bioprocess employing thermophilic and phototrophic bacteria, for the cost-effective production of pure hydrogen from multiple biomass feedstocks in small-scale, cost-effective industries. Results are summarised of the work on pretreatment technologies for optimal biodegradation of energy crops and bio-residues, conditions for maximum efficiency in conversion of fermentable biomass to hydrogen and CO2, concepts of dedicated installations for optimal gas cleaning and gas quality protocols, as well as innovative system integration aimed at minimizing energy demand and maximizing product output.The main technological objective is the construction of prototype modules of the plant which, when assembled, form the basis of a blueprint for the whole chain for converting biomass to pure hydrogen. A brief outline is presented of the progress made towards developing reactors for thermophilic hydrogen production, reactors for photoheterotrophic hydrogen production and equipment for optimal gas cleaning procedures. 相似文献
638.
The environmental impact of hydrogen production in a 2-step fermentation process from potato steam peels was identified. Based on the ISO 14040, ISO 14044, ecoinvent data base and SimaPro 7.1 software, a life cycle inventory analysis was performed. Reflecting the current state of process development, the LCA shows an impact of 4.3 points (pts) which is at least 5.7 times higher than the selected reference technologies regarded as state-of-the-art. Over half (53.5%) of the environmental impact is generated by the use of phosphate in the fermentation processes. A sensitivity analysis shows a potential impact reduction of 65.8% due to recirculation of sewage or reduction of buffer concentration. The analysis also demonstrates that the production of the process ingredients cause 98.3% of the environmental impact. The impact of the process itself is 0.07 pts which is up to 10 times lower than the reference technologies. 相似文献
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Food quality is a relevant characteristic to be transferred within eusocial insect colonies because its evaluation improves
the collective foraging efficiency. In honeybees, colony mates could directly acquire this resource characteristic during
trophallactic encounters with nectar foragers. In the present study, we focused on the gustatory responsiveness of bees that
have unloaded food from incoming foragers. The sugar sensitivity of receiver bees was assessed in the laboratory by using
the proboscis extension response paradigm. After unloading, hive bees were captured either from a colony that foraged freely
in the environmental surroundings or from a colony that foraged at an artificial feeder with a known sucrose solution. In
the first situation, the sugar sensitivity of the hive bees negatively correlated with the sugar concentration of the nectar
crops brought back by forager mates. Similarly, in the controlled situation, the highest sucrose concentration the receivers
accepted during trophallaxis corresponded to the highest thresholds to sucrose. The results indicate that first-order receivers
modify their sugar sensitivity according to the quality of the food previously transferred through trophallaxis by the incoming
foragers. In addition, trophallaxis is a mechanism capable of transferring gustatory information in honeybees. Its implications
at a social scale might involve changes in the social information as well as in nectar distribution within the colony. 相似文献