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181.
Spatially explicit sensitivity and uncertainty analysis for multicriteria-based vulnerability assessment 总被引:1,自引:0,他引:1
Bakhtiar Feizizadeh Stefan Kienberger 《Journal of Environmental Planning and Management》2017,60(11):2013-2035
This research analyses the application of spatially explicit sensitivity and uncertainty analysis for GIS (Geographic Information System) multicriteria decision analysis (MCDA) within a multi-dimensional vulnerability assessment regarding flooding in the Salzach river catchment in Austria. The research methodology is based on a spatially explicit sensitivity and uncertainty analysis of GIS-CDA for an assessment of the social, economic, and environmental dimensions of vulnerability. The main objective of this research is to demonstrate how a unified approach of uncertainty and sensitivity analysis can be applied to minimise the associated uncertainty within each dimension of the vulnerability assessment. The methodology proposed for achieving this objective is composed of four main steps. The first step is computing criteria weights using the analytic hierarchy process (AHP). In the second step, Monte Carlo simulation is applied to calculate the uncertainties associated with AHP weights. In the third step, the global sensitivity analysis (GSA) is employed in the form of a model-independent method of output variance decomposition, in which the variability of the different vulnerability assessments is apportioned to every criterion weight, generating one first-order (S) and one total effect (ST) sensitivity index map per criterion weight. Finally, in the fourth step, an ordered weighted averaging method is applied to model the final vulnerability maps. The results of this research demonstrate the robustness of spatially explicit GSA for minimising the uncertainty associated with GIS-MCDA models. Based on these results, we conclude that applying the variance-based GSA enables assessment of the importance of each input factor for the results of the GIS-MCDA method, both spatially and statistically, thus allowing us to introduce and recommend GIS-based GSA as a useful methodology for minimising the uncertainty of GIS-MCDA. 相似文献
182.
183.
The effect of light and iron(II)/iron(III) on the distribution of Tl(I)/Tl(III) in fresh water systems 总被引:1,自引:0,他引:1
The distribution of aqueous Tl(I)/Tl(III) as a function of light exposure and solution properties was studied by quantifying the oxidation states after separation with ion chromatography and on-line detection with ICP-MS. Ultraviolet irradiation of aqueous solutions containing 1 microg l(-1) Tl(III) and in equilibrium with the atmosphere increases the reduction rate. In systems with photoreduction of Fe(III)(aq) a quantitative oxidation of Tl(I)(aq) was observed, notably at low pH. The process is reversible, as indicated by formation of Tl(I) when the irradiated systems were kept in the dark. In systems with colloidal silica-stabilised ferrihydrite, UV irradiation also leads to oxidation of Tl(I)(aq), but not quantitatively. It is suggested that adsorption of thallium to the ferrihydrite determines the rate of oxidation. Detectable, but not quantitative, oxidation of Tl(I)(aq) took place when natural water samples with 1 microg l(-1) Tl(I)(aq) were exposed to either sunlight or UV-light. For these samples, the reduction was not quantitative when they were kept in the dark for 24 h. The results suggest that the light dependent iron cycle in fresh water systems strongly influences the redox state of thallium. 相似文献
184.
Stefan Norra 《Environmental science and pollution research international》2009,16(5):539-545
Background, aim, and scope In 1875, the geoscientist Walter Suess introduced several spheres, such as the lithosphere and the atmosphere to promote a
comprehensive understanding of the system earth. Since then, this idea became the dominating concept for the understanding
of the distribution of chemical elements in the system earth. Meanwhile, due to the importance of human beings on global element
fluxes, the term anthroposphere was introduced. Nevertheless, in face of the ongoing urbanization of the earth, this concept
is not any more adequate enough to develop a comprehensive understanding of global element fluxes in and between solid, liquid,
and gaseous phases. This article discusses a new concept integrating urbanization into the geoscientific concept of spheres.
Main features No geological exogenic force has altered the earth’s surface during the last centuries in such an extent as human activity.
Humans have altered the morphology and element balances of the earth by establishing agrosystems first and urban systems later.
Currently, urban systems happen to become the main regulators for fluxes of many elements on a global scale due to ongoing
industrial and economic development and a growing number of inhabitants. Additionally, urban systems are constantly expanding
and cover more and more former natural and agricultural areas. For nature, urban systems are new phenomena, which never existed
in previous geological eras. The process of the globe’s urbanization concurrently is active with the global climate change.
In fact, urban systems are a major emitter for climate active gases. Thus, beside the global changes in economy and society,
urbanization is an important factor within the global change of nature as is already accepted for climate, ecosystems, and
biodiversity.
Results Due to the fact that urbanization has become a global process shaping the earth and that the urban systems are globally cross-linked
among each other, a new geoscientific sphere has to be introduced: the astysphere. This sphere comprises the parts of the
earth influenced by urban systems. Accepting urbanization as global ongoing process forming the astysphere comprehensively
copes with the growing importance of urbanization on the creation of present geologic formations.
Discussion Anthropogenic activities occur mainly in rural and urban environments. For long lasting periods of human history, human activities
mainly were focused on hunting and agriculture, but since industrialization, urbanized areas became increasingly important
for the material and energy fluxes of earth. Thus, it seems appropriate to classify the anthroposphere into an agriculturally
and an urban-dominated sphere, which are the agrosphere (Krishna 2003) and the astysphere (introduced by Norra 2007).
Conclusions We have to realize that urban systems are deposits, consumers, and transformers of resources interacting among each other
and forming a network around the globe. Since the future of human mankind depends on the sustainable use of available resources,
only a global and holistic view of the cross-linked urban systems forming together the astysphere provide the necessary geoscientific
background understanding for global urban material and energy fluxes. If we want to ensure worth-living conditions for future
generations of mankind, we have to develop global models of the future needs for resources by the global metasystem of urban
systems, called astysphere.
Perspectives The final vision for geoscientific research on the astysphere must be to design models describing the global process of urbanization
of the earth and the development of the astysphere with respect to fluxes of materials, elements, and energy as well as with
respect to the forming of the earth’s face. Besides that, just from the viewpoint of fundamental research, the geoscientific
concept of spheres has to be complemented by the astysphere if this concept shall fully represent the system earth.
相似文献
Stefan NorraEmail: |
185.
Stefan Schrader Jürgen Bender Hans-Joachim Weigel 《Environmental pollution (Barking, Essex : 1987)》2009,157(12):3357-3362
A 2-year open-top chamber experiment with field-grown winter wheat (Triticum aestivum L. cv. Astron) was conducted to examine the effects of ozone on plant growth and selected groups of soil mesofauna in the rhizosphere. From May through June in each year, plants were exposed to two levels of O3: non-filtered (NF) ambient air or NF+ 40 ppb O3 (NF+). During O3 exposure, soil sampling was performed at two dates according to different plant growth stages. O3 exposure reduced above- and below-ground plant biomass in the first year, but had little effect in the second year. The individual density of enchytraeids, collembolans and soil mites decreased significantly in the rhizosphere of plants exposed to NF+ in both years. Differences were highest around anthesis, i.e. when plants are physiologically most active. The results suggest that elevated O3 concentrations may influence the dynamic of decomposition processes and the turnover of nutrients. 相似文献
186.
Carmen Martínez-Valenzuela Sandra Gmez-Arroyo Rafael Villalobos-Pietrini Stefan Waliszewski María Elena Caldern-Segura Rubn Flix-Gastlum Armando lvarez-Torres 《Environment international》2009,35(8):1155-1159
Genotoxic damage was evaluated in 70 agricultural workers, 25 women and 45 men, exposed to pesticides in Las Grullas, Ahome, Sinaloa, Mexico, with an average of 7 years of exposure. The effect was detected through the sister chromatid exchanges (SCE) in lymphocytes of peripheral blood and micronuclei (MN) and other nuclear anomalies (NA) in buccal exfoliated cells. Also, the influence on cellular proliferation kinetics (CPK) was studied by means of the replication index (RI) and the cytotoxic effect was examined with the mitotic index (MI). The non-exposed group consisted of 70 other persons, 21 women and 47 men from the city of Los Mochis, Sinaloa, Mexico. Significant differences between the exposed and the non-exposed groups were observed in SCE, CPK, MI, MN and NA. Analysis of variance revealed that age, gender, smoking and alcohol consumption did not have a significant effect on genetic damage. However, there was a correlation between exposure time to pesticides and SCE frequency. These results could have been due to the exposure of workers to pesticides containing different chemical compounds. This study afforded valuable data to estimate the possible risk to health associated with pesticide exposure. 相似文献
187.
Robert Gifford Leila Scannell Christine Kormos Lidia Smolova Anders Biel Stefan Boncu Victor Corral Hartmut Güntherf Kazunori Hanyu Donald Hine Florian G. Kaiser Kalevi Korpela Luisa Marie Lima Angela G. Mertig Ricardo Garcia Mira Gabriel Moser Paola Passafaro José Q. Pinheiro Sunil Saini Toshihiko Sako Elena Sautkina Yannick Savina Peter Schmuck Wesley Schultz Karin Sobeck Eva-Lotta Sundblad David Uzzell 《Journal of environmental psychology》2009
The personal assessments of the current and expected future state of the environment by 3232 community respondents in 18 nations were investigated at the local, national, and global spatial levels. These assessments were compared to a ranking of each country's environmental quality by an expert panel. Temporal pessimism (“things will get worse”) was found in the assessments at all three spatial levels. Spatial optimism bias (“things are better here than there”) was found in the assessments of current environmental conditions in 15 of 18 countries, but not in the assessments of the future. All countries except one exhibited temporal pessimism, but significant differences between them were common. Evaluations of current environmental conditions also differed by country. Citizens' assessments of current conditions, and the degree of comparative optimism, were strongly correlated with the expert panel's assessments of national environmental quality. Aside from the value of understanding global trends in environmental assessments, the results have important implications for environmental policy and risk management strategies. 相似文献
188.
The use of spectroscopic techniques (especially phosphorus-31 nuclear magnetic resonance [(31)P-NMR] and X-ray absorption near edge structure spectroscopy) has recently advanced the analysis of the speciation of P in poultry litter (PL) and greatly enhanced our understanding of changes in P pools in PL that receive alum (aluminum sulfate) to reduce water-soluble P and control ammonia emissions from poultry houses. Questions remain concerning changes of P species during long-term storage, drying, or after application of PL to cropland or for other uses, such as turfgrass. In this study, we investigated a set of six PL samples (of which three were alum-amended and three were unamended) that had been characterized previously. The P speciation was analyzed using solid-state (31)P-NMR spectroscopy, and the mineralogy was analyzed by powder X-ray diffraction (XRD) after storing the samples moist and dried for up to 5 yr under controlled conditions. The magnesium ammonium phosphate mineral struvite was identified in all but one PL samples. Struvite concentrations were generally lower in dried samples (< or = 14%) than in samples stored moist (23 and 26%). The moist samples also had higher concentrations of phosphate bound to aluminum hydroxides. Solid-state NMR spectroscopy was in general more sensitive than XRD in detecting and quantifying P species. Although phosphate associated with calcium and aluminum made up a large proportion of P species, they were not detected by XRD. 相似文献
189.
Structure and origin of the natural halogenated monoterpene MHC-1 and its concentrations in marine mammals and fish 总被引:2,自引:1,他引:1
The halogenated natural product previously named mixed-halogenated compound 1 (MHC-1) was isolated from the red seaweed Plocamium cartilagineum harvested in Helgoland, Germany. A total of 1.9mg of pure MHC-1 was obtained from 1g air-dried seaweed. The (1)H and (13)C NMR data matched those reported for a natural monoterpene isolated from this species. Thus, the structure of MHC-1 was established to be (1R,2S,4R,5R,1'E)-2-bromo-1-bromomethyl-1,4-dichloro-5-(2'-chloroethenyl)-5-methylcyclohexane. Moreover, the isolated monoterpene proved to be identical with the compound previously detected in marine mammals and fish from different locations. In addition we examined two samples of P. cartilagineum from Ireland and from the Antarctic; however MHC-1 was only present at low levels. Not only the concentrations were lower but also the pattern of polybrominated compounds differed from MHC-1. A calibrated solution of MHC-1 was used to determine correct concentrations from samples where previously only estimates existed relative to the gas chromatography-electron capture detector (GC/ECD) response of trans-chlordane, which underrated the MHC-1 concentrations by more than factor 2. The highest MHC-1 concentration determined to date in marine mammals is 0.14mgkg(-1) blubber. Significantly higher MHC-1 concentrations were determined in farmed fish with up to 2.2mgkg(-1) lipids. The samples with high concentrations of MHC-1 have in common that they were collected in proximity of the natural habitats of P. cartilagineum. 相似文献
190.