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81.
Charles E. Rzadkowolski 《欧洲藻类学杂志》2013,48(1):30-41
Laser in situ scattering and transmissometry (LISST) instruments are used to measure particle size distributions (PSDs) and volume concentrations in water. For populations of regularly shaped non-spherical particles, such as phytoplankton, the PSD produces a ‘scattering signature’ that corresponds to the shape of the particles. The objectives of this research were to describe the scattering signatures of six diatom species and to determine whether LISST instruments can be used as a tool to measure the aggregation of diatoms into larger particles. The scattering signatures of Chaetoceros muelleri var. subsalsum, Coscinodiscus wailesii, Thalassiosira weissflogii, Phaeodactylum tricornutum, Skeletonema costatum and S. marinoi were measured. The scattering signatures of individual species were consistent over time in batch culture and there were clear differences between species in terms of peak location, peak width, and relative peak height in the PSD. LISST was used to non-destructively follow the formation of diatom aggregates in the laboratory. Both rolling and warming cultures of S. costatum caused the cell chains to form aggregates, resulting in a change in the PSD, with a shift in peak position towards larger size bins. These experiments showed that the scattering signatures of unaggregated diatom species are conservative and that LISST instruments are useful tools to investigate the factors affecting diatom aggregation and disaggregation, with potential applications both in the laboratory and field. 相似文献
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83.
Jingjing Xu David Testa Proshanto K. Mukherjee 《Ocean Development & International Law》2013,44(3):225-240
While shipping is a carbon efficient transport mode, given that roughly 90% of the world trade is carried by ships, the negative impact of shipping on human health and the natural environment is significant. One of the attempts being made by the shipping industry to reduce its environmental impact is to use liquefied natural gas (LNG) as a marine fuel. This article examines the regulatory legal regime in relation to the use of LNG as marine fuel and highlights the areas where further development is necessary. 相似文献
84.
This article discusses the allocation problem in international fisheries management, which is critical to effective resource management. A number of cases where allocation problems exist are reviewed and trends identified. It is concluded that power relationships between the states involved are an important determinant of allocation outcomes. While this may seem a frustrating conclusion, it nevertheless reflects the realities of international cooperation. 相似文献
85.
Yann-Huei Song 《Ocean Development & International Law》2013,44(2):150-177
This article examines the potential threat of marine pollution caused by offshore oil and gas development activities in the disputed areas of the South China Sea (SCS) and the Spratly Islands. After addressing the potential threat of marine pollution, it discusses the legal obligations and political commitment of the SCS littoral states regarding the protection of the marine environment in the area. The role that Taiwan can play in these matters is also examined. 相似文献
86.
In the interests of increasing fish production globally, alleviating global poverty, and income generation, marine aquaculture has seen worldwide expansion over the past few decades. However, this expansion has been matched by growing concerns over its environmental impacts. This article utilizes comparative legal analysis to explore the legal systems of governance for the environmental performance of marine aquaculture in four case study countries. Two are members of the European Community (Scotland, as part of the United Kingdom, and Greece), one is a recent accession country (Slovenia), and the fourth is closely linked to the European Community albeit geographically and legally disparate (Israel). 相似文献
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Martin H. van der Meer John B. Horne Michael G. Gardner Jean‐Paul A. Hobbs Morgan Pratchett Lynne van Herwerden 《Ecology and evolution》2013,3(6):1653-1666
Extensive ongoing degradation of coral reef habitats worldwide has lead to declines in abundance of coral reef fishes and local extinction of some species. Those most vulnerable are ecological specialists and endemic species. Determining connectivity between locations is vital to understanding recovery and long‐term persistence of these species following local extinction. This study explored population connectivity in the ecologically‐specialized endemic three‐striped butterflyfish (Chaetodon tricinctus) using mt and msatDNA (nuclear microsatellites) to distinguish evolutionary versus contemporary gene flow, estimate self‐replenishment and measure genetic diversity among locations at the remote Australian offshore coral reefs of Middleton Reef (MR), Elizabeth Reef (ER), Lord Howe Island (LHI), and Norfolk Island (NI). Mt and msatDNA suggested genetic differentiation of the most peripheral location (NI) from the remaining three locations (MR, ER, LHI). Despite high levels of mtDNA gene flow, there is limited msatDNA gene flow with evidence of high levels of self‐replenishment (≥76%) at all four locations. Taken together, this suggests prolonged population recovery times following population declines. The peripheral population (NI) is most vulnerable to local extinction due to its relative isolation, extreme levels of self‐replenishment (95%), and low contemporary abundance. 相似文献
89.
Pascal Hingamp Nigel Grimsley Silvia G Acinas Camille Clerissi Lucie Subirana Julie Poulain Isabel Ferrera Hugo Sarmento Emilie Villar Gipsi Lima-Mendez Karoline Faust Shinichi Sunagawa Jean-Michel Claverie Hervé Moreau Yves Desdevises Peer Bork Jeroen Raes Colomban de Vargas Eric Karsenti Stefanie Kandels-Lewis Olivier Jaillon Fabrice Not Stéphane Pesant Patrick Wincker Hiroyuki Ogata 《The ISME journal》2013,7(9):1678-1695
Nucleo-cytoplasmic large DNA viruses (NCLDVs) constitute a group of eukaryotic viruses that can have crucial ecological roles in the sea by accelerating the turnover of their unicellular hosts or by causing diseases in animals. To better characterize the diversity, abundance and biogeography of marine NCLDVs, we analyzed 17 metagenomes derived from microbial samples (0.2–1.6 μm size range) collected during the Tara Oceans Expedition. The sample set includes ecosystems under-represented in previous studies, such as the Arabian Sea oxygen minimum zone (OMZ) and Indian Ocean lagoons. By combining computationally derived relative abundance and direct prokaryote cell counts, the abundance of NCLDVs was found to be in the order of 104–105 genomes ml−1 for the samples from the photic zone and 102–103 genomes ml−1 for the OMZ. The Megaviridae and Phycodnaviridae dominated the NCLDV populations in the metagenomes, although most of the reads classified in these families showed large divergence from known viral genomes. Our taxon co-occurrence analysis revealed a potential association between viruses of the Megaviridae family and eukaryotes related to oomycetes. In support of this predicted association, we identified six cases of lateral gene transfer between Megaviridae and oomycetes. Our results suggest that marine NCLDVs probably outnumber eukaryotic organisms in the photic layer (per given water mass) and that metagenomic sequence analyses promise to shed new light on the biodiversity of marine viruses and their interactions with potential hosts. 相似文献
90.