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481.
482.
Frøydis Gillund Anne Ingeborg Myhr 《Journal of Agricultural and Environmental Ethics》2010,23(6):527-550
The future of salmon aquaculture depends on the adoption of alternative feed resources in order to reduce the need for fish
meal and fish oil. This may include resources such as species from lower trophic levels, by-products and by-catch from fisheries
and aquaculture, animal by-products, plants, genetically modified (GM) plants, nutritionally enhanced GM plants and products
from microorganisms and GM microorganisms. Here, we report on a deliberative assessment of these alternative feed resources,
involving 18 participants from different interest groups within Norwegian salmon aquaculture. The participants defined a broad
range of appraisal criteria concerning health and welfare issues, economical issues, environmental issues, and knowledge and
social issues. A number of uncertainties, in the form of incomplete knowledge, diverging opinions, and context specific factors
were identified when the participants evaluated the alternatives. Our findings support the need for more research on the suitability
of alternative feed resources for farmed salmon. Additionally, the study underlines the importance of facilitating deliberative
assessments in order to map the plurality of perspectives and explore qualitative aspects of uncertainty. Such initiatives
improve the information base upon which decisions on future feed resources for farmed salmon are made. 相似文献
483.
Leonardo Gucciardo Anne Uyttebroek Ivo De Wever Marleen Renard Filip Claus Roland Devlieger Liesbeth Lewi Luc De Catte Jan Deprest 《黑龙江环境通报》2011,31(7):678-688
Sacrococcygeal teratoma (SCT) is one of the most common tumors in newborns with a birth prevalence of up to 1 in 21 700 births. Routine fetal anomaly screening programs allow for prenatal diagnosis in many cases. Fetal ultrasound with Doppler evaluation and more recently magnetic resonance imaging may be used to document the extent of the tumor as well as identifying the population at risk for serious fetal complications. Rapidly growing SCT and highly vascularized tumors are more likely to have hemodynamic repercussions. Fetal hydrops is usually considered as a poor prognostic marker and a potential indicator for fetal intervention. Newborns with SCT require stabilization prior to early surgical resection. In case of malignancy additional chemotherapy may be required. SCT may result in significant morbidity, either directly or as a consequence of surgical therapy. Careful postnatal follow-up is required for timely identification and treatment of complications as well as recurrence. This paper aims to review the perinatal management of this condition. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
484.
PD Dr. Rolf Altenburger Dr. Dana Kühnel Martin Bittens Dr. Birgit Daus Dr. Werner Brack Dr. Florian Centler Prof. Dr. Hauke Harms Dr. Martin Thullner Dr. Lukas Y. Wick Prof. Dr. Kai-Uwe Goss Prof. Dr. Frank-Dieter Kopinke Dr. Katrin Mackenzie Dr. Anja Miltner PD Dr. Matthias Liess Dr. Rainer Wennrich Dr. Anne E. Berns PD Dr. Peter Burauel 《Environmental Sciences Europe》2010,22(4):502-506
485.
Lucile Gentaz Tiziana Lombardo Claudine Loisel Anne Chabas Marta Vallotto 《Environmental science and pollution research international》2011,18(2):291-300
Purpose
Throughout history, a consequent part of the medieval stained glass windows have been lost, mostly because of deliberate or accidental mechanic destruction during war or revolution, but, in some cases, did not withstand the test of time simply because of their low durability. Indeed, the glasses that remain nowadays are for many in a poor state of conservation and are heavily deteriorated. Under general exposure conditions, stained glass windows undergo different kinds of weathering processes that modify their optical properties, chemistry, and structure: congruent dissolution, leaching, and particle deposition (the combination of those two leading together to the formation of neocrystallisations and eventually crusts). Previous research has studied the weathering forms and the mechanisms from which they are originated, some others identified the main environmental parameters responsible for the deterioration and highlighted that both intrinsic (glass composition) and extrinsic (environmental parameters) factors influence glass degradation. Nevertheless, a clear quantification of the impact of the different deterioration extrinsic factors has not been performed. 相似文献486.
487.
Terry L Tudor Anne C Woolridge Margaret P Bates Paul S Phillips Sharon Butler Keith Jones 《Waste management & research》2008,26(3):233-240
Changes in environmental legislation and standards governing healthcare waste, such as the Hazardous Waste Regulations are expected to have a significant impact on healthcare waste quantities and costs in England and Wales. This paper presents findings from two award winning case study organizations, the Cardiff and Vale NHS Trust and the Cornwall NHS Trust on 'systems' they have employed for minimizing waste. The results suggest the need for the development and implementation of a holistic range of systems in order to develop best practice, including waste minimization strategies, key performance indicators, and staff training and awareness. The implications for the sharing of best practice from the two case studies are also discussed. 相似文献
488.
489.
Sorption, desorption and mineralisation of the herbicides glyphosate and MCPA in samples from two Danish soil and subsurface profiles 总被引:3,自引:0,他引:3
Sørensen SR Schultz A Jacobsen OS Aamand J 《Environmental pollution (Barking, Essex : 1987)》2006,141(1):184-194
The vertical distribution of the sorption, desorption and mineralisation of glyphosate and MCPA was examined in samples from two contrasting soil and subsurface profiles, obtained from a sandy agricultural site and a non-agricultural clay rich site. The highest mineralisation of [14C-methylen]glyphosate, with 9.3-14.7% degraded to 14CO2 within 3 months was found in the deepest sample from the clay site. In the deeper parts of the sandy profile high sorption and low desorption of glyphosate coincided with no or minor mineralisation indicating a limited glyphosate bioavailability. MCPA was readily mineralised except in the deepest samples from both sites. The highest MCPA mineralisation was detected just below the surface layers with 72% or 44% degraded to 14CO2 at the sandy or the clay sites, respectively. MCPA sorped to a minor extent in all samples and no indications of sorption-controlled mineralisation was revealed. None of the herbicides were mineralised under anoxic conditions. 相似文献
490.
Besides the "normal" challenge of obtaining adequate intake rates in a patchy and dangerous world, shorebirds foraging in intertidal habitats face additional environmental hurdles. The tide forces them to commute between a roosting site and feeding grounds, twice a day. Moreover, because intertidal food patches are not all available at the same time, shorebirds should follow itineraries along the best patches available at a given time. Finally, shorebirds need additional energy stores in order to survive unpredictable periods of bad weather, during which food patches are covered by extreme tides. In order to model such tide-specific decisions, we applied stochastic dynamic programming in a spatially explicit context. Two assumptions were varied, leading to four models. First, birds had either perfect (ideal) or no (non-ideal) information about the intake rate at each site. Second, traveling between sites was either for free or incurred time and energy costs (non-free). Predictions were generated for three aspects of foraging: area use, foraging routines, and energy stores. In general, non-ideal foragers should feed most intensely and should maintain low energy stores. If traveling for such birds is free, they should feed at a random site; otherwise, they should feed close to their roost. Ideal foragers should concentrate their feeding around low tide (especially when free) and should maintain larger energy stores (especially when non-free). If traveling for such birds is free, they should feed at the site offering the highest intake rate; otherwise, they should trade off travel costs and intake rate. Models were parameterized for Red Knots (Calidris canutus) living in the Dutch Wadden Sea in late summer, an area for which detailed, spatially explicit data on prey densities and tidal heights are available. Observations of radio-marked knots (area use) and unmarked knots (foraging routines, energy stores) showed the closest match with the ideal/non-free model. We conclude that knots make state-dependent decisions by trading off starvation against foraging-associated risks, including predation. Presumably, knots share public information about resource quality that enables them to behave in a more or less ideal manner. We suggest that our modeling approach may be applicable in other systems where resources fluctuate in space and time. 相似文献