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251.
Sustainability assessment of entire forest value chains: Integrating stakeholder perspectives and indicators in decision support tools 总被引:1,自引:0,他引:1
The optimization of value chains is an important process to promote sustainable development, since value chains are closely linked to the satisfaction of human needs and combine different driving forces for environmental change. This article presents a methodological approach for the participatory development of value-chain wide sustainability indicator sets and their integration into a decision support tool in the specific case study of the chain “construction and refurbishment with wood”. There are numerous indicator sets for sustainable development of forests and sustainable forestry available at different levels, ranging from local, regional and national to global scale assessments. Some efforts were also made to integrate later production stages of forest value chains (such as wood processing) in the assessment scope (e.g. for chain-of-custody certification). However, no indicator set has so far been available covering environmental, social and economic aspects for the entire value chain of building with timber. This gap was closed through applied sustainability research in the project “Holzwende 2020: Sustainable future markets for wood in the building sector”. 相似文献
252.
Uwe Heiser Stefan Norra Doris Stüben Magnus von Wagner 《Environmental Sciences Europe》1999,11(2):73-78
For the application of our method for the sequential extraction of heavy metals from microsamples presented in part 1 (“Sequentielle Schwermetallextraktion von Mikroproben” — “Sequential Extraction of Heavy Metals from Micro Samples”) an investigation was carried out to evaluate airborne dust fallout and street sediments at two urban sites where different heavy metal immission rates occur due to traffic influence. In the street sediments the total concentrations of zinc, copper and lead was three to fivefold higher in the silt and clay fraction (< 63 μm) than in the particle size fraction (< 1,12 mm), but showed nearly the same mobilisation behaviour. The dust samples showed equal mobilisation behaviour as the street sediments for copper and lead, while zinc was considerably more mobile in the dust samples: In extraction steps I–IV (I: mobile fraction; II: easily deliverable fraction; III: fraction bound to manganese oxides; IV: fraction bound organic to matter) zinc, copper and lead in street sediments, as well as copper and lead in dust samples, were dissolved to 40–70%, whereas about 80% of zinc in the dust samples was already dissolved in extraction step I. 相似文献
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This study examines what happens when contentious lay citizens harness the technical-ecological repertoire of experts as means of challenging nature conservation policy. The causes, manifestations, and implications of this phenomenon are elucidated through a critical discourse analysis. The case study is based on the wolf reintroduction project in Europe, with particular focus on Sweden, using illegal hunting discussions as a point of entry within the hunting community. It reveals the deployment of three topoi, which are defined as stock arguments situated within a discourse. Analysis shows how while some topoi often incur short-term gains in the debate because of their scientific guise, they are fundamentally relegated as folk science (or “barstool biology”) by government experts and, in some cases, contribute to the further marginalization of other knowledges. Acquiescence to this discourse is shown to greatly impede the debate. Finally, the study shows how lack of trust in the public dialog, which hunters openly recognize to be colonized by ecological expertise, results in increasingly noncommunicative forms of resistance toward policy. 相似文献
255.
Estimating the relevance of engineered carbonaceous nanoparticle facilitated transport of hydrophobic organic contaminants in porous media 总被引:1,自引:0,他引:1
Thilo Hofmann Frank von der Kammer 《Environmental pollution (Barking, Essex : 1987)》2009,157(4):1117-1126
Naturally occurring nanoparticles (NP) enhance the transport of hydrophobic organic contaminants (HOCs) in porous media. In addition, the debate on the environmental impact of engineered nanoparticles (ENP) has become increasingly important. HOC bind strongly to carbonaceous ENP. Thus, carbonaceous ENP may also act as carriers for contaminant transport and might be important when compared to existing transport processes. ENP bound transport is strongly linked to the sorption behavior, and other carbonaceous ENP-specific properties. In our analysis the HOC-ENP sorption mechanism, as well as ENP size and ENP residence time, was of major importance. Our results show that depending on ENP size, sorption kinetics and residence time in the system, the ENP bound transport can be estimated either as (1) negligible, (2) enhancing contaminant transport, or (3) should be assessed by reactive transport modeling. One major challenge to this field is the current lack of data for HOC-ENP desorption kinetics. 相似文献
256.
An analysis of the population genetics of the meiofaunal polychaete Petitia amphophthalma Siewing, 1956, in which the RAPD-PCR method was applied to 103 individuals from eight populations, some of them very far
apart (Atlantic: Florida, Tenerife, France; Mediterranean: two Greek islands, Tunisia; Red Sea: Egypt), gave closely reproducible
results. In the band patterns produced with 13 decamer primers, a total of 195 genetic characters was detected. The data were
evaluated by a number of methods, including the cluster programs UPGMA, WPGMA and neighbour-joining. The detected genetic
distances between the populations vary between 58.9 and 66.6, but 97% of the genetic characters, although polymorphic, are
found in at least two populations and usually in all the others as well. Phenograms of the analyses find four population clusters
[Florida, France (Atlantic), the Mediterranean and Tenerife]. They are, however, not completely congruent and show low bootstrap
values at the junction points of the clusters (with the exception of the Tenerife cluster). Mediterranean P. amphophthalma form a cohesive population, although within it the genetic distances are graded in parallel with the geographic distances
between the sites. The colonization of Tenerife, an island of relatively recent volcanic origin, can be taken as evidence
that this meiofaunal species can become dispersed not only along coastlines but also across expanses of open water. However,
the severely restricted variability of these populations implies that in this case a founder effect has operated, and that
transport over open water is not a routine event but extremely rare. The absence of the species on the Australian coast and,
for instance, on the Galapagos Islands indicates that there has been no continuous gene flow across the oceans. The idea that
all the populations investigated belong to one cosmopolitan species is discussed.
Received: 17 October 1997 / Accepted: 15 April 1998 相似文献
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