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821.
Functional Ecosystems and Biodiversity Buzzwords   总被引:1,自引:0,他引:1  
Abstract: Several increasingly popular paradigms in conservation remove organismal information and life-history requirements from management planning with claims that species-specific information is not necessary to the understanding and management of "ecosystem function" and may therefore be discarded. Although several authors have called attention to the fact that ecosystem management has not yet been articulated sufficiently to comprise an adequate paradigm for wildlife protection, there has been a series of suggestions paralleling ecosystem management's popularity that the perceived or imagined emergent properties of communities should be at the root of conservation planning. Such reductions most commonly take the form of abstracted species diversity measures that may be irrelevant or misleading with respect to site-specific planning and to the monitoring of specific management treatments. Following earlier examinations of ecosystem management, I emphasize that several of its apparent outgrowths may be too vague to inform specific recommendations, that the historical mechanics of "ecosystem processes" are essentially unknowable, and that anecdotal definitions of ecosystems allow one to justify virtually any protocol as management. The primacy of process-dependent, landscape-functional considerations in conservation planning is specious in the absence of species- and population-specific information, which should form the foundation for understanding such processes in the first place. Only by viewing nature in terms of the relationships between processes and organisms, rather than in terms of emergent properties of organismal assemblages or abiotic factors divorced from organismal data, can conservation plans claim to protect biological elements.  相似文献   
822.
Productivity in Conservation Research in the Southern Hemisphere   总被引:2,自引:0,他引:2  
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823.
Environmental Science and Pollution Research - Levulinic acid is a carboxylic acid present in industrial downstream. It is an important chemical and can be transformed into various important...  相似文献   
824.
Based on data from a Qualtrics panel, this study examines Chinese citizens’ motivations for information seeking about air pollution. Results from structural equation modelling indicate that information insufficiency, negative affect, attitudes toward seeking, and perceived information gathering capacity are positively related to information seeking. Informational subjective norms, however, were not significantly related to information seeking. Further, participants with more knowledge and higher risk perception were more likely to desire more information about air pollution. These results suggest that communication campaigns should highlight individuals’ personal risks and self-efficacy to encourage greater information seeking about air pollution among Chinese citizens. Emotional appeal may serve as an effective strategy as well.  相似文献   
825.
Russian Journal of Ecology - There are increasing evidences documenting the negative impact of exotic species including mosquitofish, Gambosi affinis, in Iran. Meanwhile, recent climate change in...  相似文献   
826.
Environmental Science and Pollution Research - The Moravian-Silesian region of the Czech Republic with its capital city Ostrava is a European air pollution hot spot for airborne particulate matter...  相似文献   
827.
Acid mine drainage from mine tailings at Selebi Phikwe, eastern Botswana, has been investigated using a combination of total decomposition, sequential extraction, X-ray diffraction, Mössbauer spectroscopy, and SEM analyses of solid phase samples, water analyses, isotopic analyses, and geochemical modeling. The principal ferric phases in the seepage stream sediments are jarosite and goethite, which incorporate Ni and Cu. The Mössbauer spectroscopy (MS) indicated exclusively 3+ oxidation state of iron with typical features of ferric hydroxides/sulfates. A fraction of dissolved sulfate is also sequestered in gypsum which precipitates further downstream. Significant portions of Fe, Ni, and Cu are transported in suspension. Values of pH decreased downstream due to H+ generated by the precipitation of jarosite. Values of δ2H and δ18O indicate evaporation of pore water in the mine tailings before seepage. Values of δ34S(SO4) are consistent with the oxidation of sulfides, but sample from the seepage face is affected by dissolution of gypsum. No minerals of Ni and Cu were detected and the principal attenuation processes seem to be adsorption and co-precipitation with jarosite. Higher contents of Cu are sequestered in solid phases compared to Ni, in spite of much higher dissolved Ni concentrations. Based on the speciation calculations, seepage water is undersaturated with respect to all Ni and Cu phases and adsorption and co-precipitation with jarosite seems to be the principal attenuation processes. Direct geochemical modeling was able to reproduce downstream pH trends, thus confirming the precipitation of jarosite as the principal pH-controlling process.  相似文献   
828.
In this study, chitosan and bio-based activated carbon obtained from sugarcane bagasse biowaste were used for the synthesis of efficient sorbent for Cu(II) and Cd(II) ion via precipitation method. The prepared material was enriched with amino groups through grafting tetraethylenepentamine and tested for heavy metal remediation from water samples. The influence of pH was investigated showing optimum sorption at pH 6 for Cu(II) and Cd(II). Sorption tests, explained by means of the most common sorption models, evidenced that the best performances were reached pointing out the promising application of the prepared sorbent for water purification treatments: Uptake kinetics are relatively fast: the equilibrium was reached within 140 min; and the kinetic profiles were preferentially fitted by the pseudo-second order rate equation. Sorption isotherms are fitted by Langmuir equation. The sorbent showed high metal ion sorption capacity with negligible influence of ion strength. The maximum sorption capacities reached 3.44 and 2.38 mmol g??1 for Cu(II) and Cd(II), respectively at 298 K. Thermodynamic parameters were evaluated through variation of temperature. The sorption is unfavorable at elevated temperatures. Metal ions were successfully desorbed using 1 M HNO3 solution.  相似文献   
829.
The patterns of growth and development have been studied in L. maculatus early life stages of different ecological groups (pelagic and demersal) from Kongsfjorden and Billefjorden (the northwestern coast of West Spitsbergen). It has been found that the growth rate of larvae markedly increases by age 2+ (stage L2), which is due to their transition to exogenous feeding. Consideration is given to changes in the length and condition of the lipid sac (a provisory organ) in the period of its formation, growth, and resorption in the course of ontogeny. The lipid sac reaches the maximum size at stage L4* and is resorbed at stage L5. Analysis of individual variation in the size and body weight of fish early life stages provides the possibility to evaluate the adaptation capacity of a species under specific conditions of the Arctic.  相似文献   
830.
In recent years, extremely low-frequency electromagnetic field (ELF-EMF) has received considerable attention for its potential biological effects. Numerous studies have shown the role of ELF-EMF in behaviour modulation. The aim of this study was to investigate the effect of short-term ELF-EMF (50 Hz) in the development of anxiety-like behaviour in rats through change hypothalamic oxidative stress and NO. Ten adult male rats (Wistar albino) were divided in two groups: control group—without exposure to ELF-EMF and experimental group—exposed to ELF-EMF during 7 days. After the exposure, time open field test and elevated plus maze were used to evaluate the anxiety-like behaviour of rats. Upon completion of the behavioural tests, concentrations of superoxide anion (O2·?), nitrite (NO2 ?, as an indicator of NO) and peroxynitrite (ONOO?) were determined in the hypothalamus of the animals. Obtained results show that ELF-EMF both induces anxiety-like behaviour and increases concentrations of O2·? and NO, whereas it did not effect on ONOO? concentration in hypothalamus of rats. In conclusion, the development of anxiety-like behaviour is mediated by oxidative stress and increased NO concentration in hypothalamus of rats exposed to ELF-EMF during 7 days.  相似文献   
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