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121.
122.
123.
Helmut Metzner 《Die Naturwissenschaften》1973,60(11):507-515
124.
Helmut Altner 《Die Naturwissenschaften》1985,72(2):57-61
In order to discuss the justified and humane demands for more animal protection in science we need first to achieve conceptual clarity. A simple separation of highly developed animals from less developed ones is hardly possible. Although we have no reliable way of assessing pain and suffering in animals we still have the responsibility for protecting them. However, scientists will always require animal experimentation in order to further the understanding of ourselves and to improve health. These experiments should follow strict guidelines. Concrete measures for animal protection must be adapted to each case and the consequences carefully thought out. 相似文献
125.
Helmut Hölder 《Die Naturwissenschaften》1975,62(12):545-554
The term “Jurassic” refers to a manifold rock series of an epoch in the earth's history and its organic enclosures, from which-despite the lack of detail -a picture of earth surface and its life at that time can be reconstructed. This article presents the position of research and the problems it faces, which are partly of an objective and partly of a methodical nature. 相似文献
126.
The European critical levels (CLs) to protect vegetation are expressed as an accumulative exposure over a threshold of 40 ppb (nl l(-1)). In view of the fact that these chamber-derived CLs are based on ozone (O(3)) concentrations at the top of the canopy the correct application to ambient conditions presupposes the application of Soil-Vegetation-Atmosphere-Transfer (SVAT) models for quantifying trace gas exchange between phytosphere and atmosphere. Especially in the context of establishing control strategies based on flux-oriented dose-response relationships, O(3) flux measurements and O(3) exchange simulations are needed for representative ecosystems. During the last decades several micrometeorological methods for quantifying energy and trace gas exchange were developed, as well as models for the simulation of the exchange of trace gases between phytosphere and atmosphere near the ground. This paper is a synthesis of observational and modeling techniques which discusses measurement methods, assumptions, and limitations and current modeling approaches. Because stomatal resistance for trace gas exchange is parameterized as a function of water vapor or carbon dioxide (CO(2)) exchange, the most important micrometeorological techniques especially for quantifying O(3), water vapor and CO(2) flux densities are discussed. A comparison of simulated and measured O(3) flux densities shows good agreement in the mean. 相似文献
127.
Helge Torgersen Gerhard Soja Ines Janssen Helmut Gaugitsch 《Environmental science and pollution research international》1998,5(2):89-93
The risk assessment of genetically-modified plants pursuant to Annex II B of EU Directive 94/15/EC assumes that it is possible
to infer the environmental impacts of a crop plant from its characteristics, so most of Annex II should also be applicable
to conventional plants. To test this, we surveyed reports on the ecological impacts of the cultivation of non-transgenic crop
plants with novel or improved traits and, in three cases, investigated whether Annex II B would have been adequate to indicate
the effects. Such an assessment appears to be feasible only if the time frame on which it is based is short, so that long-term
effects cannot be assessed. Secondly, the plant must be genetically homogenous which is not always granted, e.g. with forest-trees.
Thirdly, the cultivation area must be defined. Differences in the behaviour of foreign plants between their original and cultivation
habitats may be ecologically relevant and should be assessed. In the (few) cases where direct inference of the observed effects
was possible from inherent traits, these effects often correlated with poor adaptation to local environmental conditions.
The ecological impacts of traits that had been introduced in order to overcome poor adaptation may differ widely according
to the way in which the traits are exploited. In practice, the effects of agricultural measures are more important than the
effects of gene transfer and invasiveness, although the latter currently play a major role in risk assessment. In the light
of these deliberations, a modification of Annex II B of EU Directive 94/15/EC is suggested. 相似文献
128.
Archetypical patterns and trajectories of land systems in Europe 总被引:1,自引:0,他引:1
Levers Christian Müller Daniel Erb Karlheinz Haberl Helmut Jepsen Martin Rudbeck Metzger Marc J. Meyfroidt Patrick Plieninger Tobias Plutzar Christoph Stürck Julia Verburg Peter H. Verkerk Pieter J. Kuemmerle Tobias 《Regional Environmental Change》2018,18(3):715-732
Regional Environmental Change - Assessments of land-system change have dominantly focused on conversions among broad land-use categories, whereas intensity changes within these categories have... 相似文献
129.
Beyene A Kassahun Y Addis T Assefa F Amsalu A Legesse W Kloos H Triest L 《Environmental monitoring and assessment》2012,184(11):7053-7063
Although waste from coffee processing is a valuable resource to make biogas, compost, and nutrient-rich animal food, it is usually dumped into nearby water courses. We carried out water quality assessment at 44 sampling sites along 18 rivers that receive untreated waste from 23 coffee pulping and processing plants in Jimma Zone, Ethiopia. Twenty upstream sampling sites free from coffee waste impact served as control, and 24 downstream sampling sites affected by coffee waste were selected for comparison. Physicochemical and biological results revealed a significant river water quality deterioration as a result of disposing untreated coffee waste into running water courses. During coffee-processing (wet) season, the highest organic load (1,900?mg/l), measured as biochemical oxygen demand, depleted dissolved oxygen (DO) to a level less than 0.01?mg/l, and thus curtailed nitrification. During off season, oxygen started to recuperate and augmented nitrification. The shift from significantly elevated organic load and reduced DO in the wet season to increased nitrate in the off season was found to be the determining factor for the difference in macroinvertebrate community structure as verified by ordination analysis. Macroinvertebrate diversity was significantly reduced in impacted sites during the wet season contrary to the off season. However, there was a significant difference in the ratio of sensitive to pollution-tolerant taxa in the off season, which remained depreciated in the longer term. This study highlights the urgency of research exploring on the feasibility of adopting appropriate pollution abatement technologies to implement ecologically sound coffee-processing systems in coffee-growing regions of Ethiopia. 相似文献
130.
Due to its rapid industrialization and urbanization, China faces the daunting challenge of sharply growing energy and resource
consumption. It is now indispensable for the nation to alter its course of development into more sustainable paths in terms
of energy and resource efficiency. In this paper, we discuss the energy intensity of the industrial sectors of the Yangtze
River Delta, consisting of Shanghai City and the neighboring province of Jiangsu—the fastest economically developing region
of the country—and argue possible strategies for energy efficient industrial activities there. We first examine the historical
trends of energy intensity associated with industrial sectors and study the factors affecting the evolution of these trends
by applying decomposition analysis. We then argue that if “business as usual” (BAU) development patterns are continued, energy
intensity level in both regions may surpass China’s policy targets in 2010, and GDP growth as well as energy consumption will
exceed possible pathways under current policy targets by 2020. Thus, appropriate measures are urgently needed to lower energy
intensity and consumption. Based upon these analyses as well as the Chinese government’s policy orientation, we propose two
options as alternative scenarios for improving practices in energy-intensive industries, particularly targeting the cement
and steel production sectors. These options are: (1) diffusion of highly energy efficient technologies into these industries,
and (2) promotion of a circular economy and industrial symbiosis. We highlight that these options can potentially lead to
energy savings and reductions in resource consumption associated with industrial activities and can serve as a regional model
for more sustainable industrial activities in China. 相似文献