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811.
Green waste is increasingly extracted from the material recycling chain and, as a result of the financial subsidy arising from the German renewable energy law for the generation of energy from renewable raw materials; it is fed into the energy recovery process in biomass power stations. A reduction in climate relevant gases is also linked to the material recovery of green waste – in particular when using composts gained from the process as a new raw material in different types of potting compost and plant culture media as a replacement for peat. Unlike energy recovery, material valorisation is not currently subsidised. Through the analysis of material and energy valorisation methods for green waste, with particular emphasis on primary resource consumption and CO2-balance, it could be determined that the use of green waste for energy generation and its recovery for material and peat replacement purposes can be considered to be on a par. Based on energy recovery or material oriented scenarios, it can be further deduced that no method on its own will achieve the desired outcome and that a combination of recycling processes is more likely to lead to a significant decrease of greenhouse gas emissions.  相似文献   
812.
813.
We propose the wildlife premium mechanism as an innovation to conserve endangered large vertebrates. The performance‐based payment scheme would allow stakeholders in lower‐income countries to generate revenue by recovering and maintaining threatened fauna that can also serve as umbrella species (i.e., species whose protection benefits other species with which they co‐occur). There are 3 possible options for applying the premium: option 1, embed premiums in a carbon payment; option 2, link premiums to a related carbon payment, but as independent and legally separate transactions; option 3, link premiums to noncarbon payments for conserving ecosystem services (PES). Each option presents advantages, such as incentive payments to improve livelihoods of rural poor who reside in or near areas harboring umbrella species, and challenges, such as the establishment of a subnational carbon credit scheme. In Kenya, Peru, and Nepal pilot premium projects are now underway or being finalized that largely follow option 1. The Kasigau (Kenya) project is the first voluntary carbon credit project to win approval from the 2 leading groups sanctioning such protocols and has already sold carbon credits totaling over $1.2 million since June 2011. A portion of the earnings is divided among community landowners and projects that support community members and has added over 350 jobs to the local economy. All 3 projects involve extensive community management because they occur on lands where locals hold the title or have a long‐term lease from the government. The monitoring, reporting, and verification required to make premium payments credible to investors include transparent methods for collecting data on key indices by trained community members and verification of their reporting by a biologist. A wildlife premium readiness fund would enable expansion of pilot programs needed to test options beyond those presented here. Mejora de la Conservación, Servicios del Ecosistema y Calidad de Vida Local Mediante un Mecanismo de Compensación de Vida Silvestre  相似文献   
814.
This paper examines a first version of a Comprehensive Action Determination Model (CADM) of ecological behaviour that incorporates intentional, normative, situational, and habitual influences on environmentally friendly behaviour. The main assumptions of the theory of planned behaviour (TPB), the norm-activation model (NAM), the theoretical concept of habit and the ipsative theory of behaviour were integrated into a comprehensive model. The model was tested using a structural equation modelling approach on a sample of 389 students in the domain of travel mode choice and compared to established less comprehensive models (TPB, NAM and a combination of both). The results show that all compared models had a good to excellent model fit and explained a substantial amount of variation in travel mode choice. The CADM, however, explained the greatest degree of variation as compared with the other models, at 65%. Subjective and objective situational constraints were responsible for most of the variation in travel mode choice in the CADM, but intentions and habits also had a significant impact. The influence of social and personal norms was mediated by habits and intention, while habits moderated the relationship between intention and behaviour. The importance of the CADM as a framework for other domains of ecological behaviour is also discussed.  相似文献   
815.
A fiber optic transflection dip probe (FOTDP) system was developed for in situ and real-time monitoring of the transport of gas phase ozone in unsaturated porous media. A unique property of this system is the employment of a dip probe, which is inserted within the porous media. At the probe's tip, incoming light interacts with gas phase ozone and is partially reflected back into the probe by a mirror attached to the tip. Calibration of the FOTDP system was successfully carried out with various ozone concentrations using a column packed with glass beads. The ozone breakthrough curves (BTCs) were obtained by converting normalized UV intensities into gas phase ozone concentrations. The FOTDP system worked well for in situ monitoring of gas phase ozone using a column packed with sand under various water saturations in the presence of SOM and reflected the ideal transport phenomena of gas phase ozone for various flow rates.  相似文献   
816.
Stabilization of soil contaminated with trace elements is a remediation practice that does not reduce the total content of contaminants, but lowers the amounts of mobile and bioavailable fractions. This study evaluated the efficiency of Fe(0) to reduce the mobility and bioavailability of Cr, Cu, As and Zn in a chromated copper arsenate (CCA)-contaminated soil using chemical, biochemical and biotoxicity tests. Contaminated soil was stabilized with 1% iron grit. This treatment decreased As and Cr concentrations in leachates (by 98% and 45%, respectively), in soil pore water (by 99% and 94%, respectively) and in plant shoots (by 84% and 95%, respectively). The stabilization technique also restored most of analyzed soil enzyme activities and reduced microbial toxicity, as evaluated by the BioTox test. After stabilization, exchangeable and bioaccessible fractions of Cu remained high, causing some residual toxicity in the treated soil.  相似文献   
817.
- DOI: http://dx.doi.org/10.1065/espr2006.01.295 Background Many organic micropollutants occur at trace concentrations in municipal wastewater effluents and in the aquatic environment. Some of these xenobiotic chemicals can be considered as 'emerging' contaminants and some are suspect to have endocrine disrupting effects. Among the latter are nonylphenol (NP), octylphenol (OP) and bisphenol A (BPA), which deserve special attention due to their ubiquitous occurrence in the aquatic environment. The complexing agents benzotriazole (BT) and tolyltriazole (TT) are applied as anticorrosive agents (e.g. in cooling and hydraulic fluids, in antifreezing fluids, in aircraft deicing fluids, in dish washing liquids for silver protection), as antifogging agents and as intermediates for the synthesis of various chemicals. The environmental occurrence of NP and OP is caused by the fact that they are intermediate products (metabolites) in the biodegradation of alkylphenol polyethoxylate surfactants. BPA is globally used for the production of polycarbonate and epoxy resins. Methods BT, TT, NP, OP and BPA were quantitatively determined in municipal wastewater effluents in Switzerland and in the Glatt River. The analytes were enriched by solid-phase enrichment. BT and TT were determined underivatized by electrospray LC/tandem MS. Reversed-phase LC was performed on octylsilica columns with isocratic water/methanol elution. Multiple reaction monitoring of the positive ions provided selective and sensitive detection for reliable quantifications. NP, OP and BPA were determined by GC/MS after derivatization with N-methyl-N-(trimethylsilyl)-trifluoroacetamide. Results and Discussion BT and TT concentrations in primary and secondary effluents of municipal wastewater treatment plants varied from below 10 to 100 μg/L. The ranges of the concentrations in the Glatt River in ng/L were 636–3,690 for BT, 122–628 for TT, 68–326 for NP, 6–22 for OP and 9–76 for BPA. The corresponding mass flows in g/d were 93–1,870 for BT, 18–360 for TT, 24–183 for NP, 1–16 for OP and 2–72 for BPA. The concentrations and mass flows of NP in the River Glatt were drastically lower than the analogous values found 15 years ago. Thus, a substantially decreased environmental exposure can be observed due to the reduction of the use of alkyphenol polyethoxylate surfactants in Switzerland. The current concentrations of NP, OP and BPA are within the ranges reported for weakly impacted surface waters. Conclusion The investigated contaminants occur at quantitatively measurable but varying concentrations in municipal wastewaters and in the Glatt River reflecting their ubiquitous input into wastewaters and their different behaviour during biological wastewater treatment.  相似文献   
818.
Atmospheric inversions have proven to be useful tools, showing for example the likely existence of a large terrestrial carbon sink in the northern mid-latitudes. However, as we go to smaller spatial scales the uncertainties in the inversions increase rapidly, and the task of finding the distribution of the sink between North America, Europe and Asia has been shown to be very difficult. The uncertainty in the fluxes due to network selection, transport model error and inversion set up tends to be too high for studying either net annual fluxes or interannual variability on spatial scales such as the North American Boreal or Eurasian Boreal regions. We discuss the path forward; to couple together the atmospheric inversions with process based terrestrial carbon models, creating carbon data assimilation systems. Such systems are being developed now and could prove to be very powerful. The multi-disciplinary nature of the data assimilation system requires information from flux towers, soil and above ground biomass inventories, remote sensed fields, atmospheric CO2 concentrations and climate data as well as model development and will need a massive community effort if it will succeed.  相似文献   
819.
Levels of radionuclides in seven species of marine brown algae and Ulva were determined to establish a baseline for the Northern Pacific Ocean/Bering Sea (Aleutian Islands). There were differences in levels among algal species and locations (Amchitka Island vs Kiska Island). No values were above the minimum detectable activity (MDA) level for (137)Cs, (129)I, (60)Co, (152)Eu, (90)Sr, and (99)Tc. There were interspecific differences in some radionuclides: Ulva lactuca (=Ulva fenestrata) had the highest levels of (241)Am, Alaria fistulosa had the highest levels of (239,240)Pu, and Fucus distichus (=Fucus gardneri) had the highest levels of (234)U, (235)U, and (238)U. However, levels of all radionuclides were generally low and near the MDA for all isotopes. Although Amchitka Island had higher levels of (239,240)Pu than Kiska, the differences were very small and not significant biologically. The data indicate that algae can be useful bioindicators of actinides because they accumulate them at very low environmental levels, allowing them to provide early warning of any potential seepage of radionuclides into the marine environment. Further, the data indicate that some species (the intertidal Fucus) are better accumulators than others, and these should be used as bioindicators in future monitoring schemes.  相似文献   
820.
The goal of this study was to evaluate working postures in 9 operations of poultry farming for broiler chickens for 14 body segments with 4 categories, and for fingers with 14 categories. Overall, the farmers commonly bent almost all their body segments and used power grips. The operations of cleaning with water wand and inspecting chickens seemed light work because the farmers walked around most of their working time. The operations of detaching base from hanging feeder and attaching base to hanging feeder had the farmers continue squatting to handle the feeders close to the floor. The farmers also repeatedly bent their trunks in shoveling feces, unloading a box of chicks, and releasing chicks. A power grip was frequently observed due to using tools with round handles. Workplace design to raise working height would be necessary for a better working environment for broiler farmers.  相似文献   
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